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Dietary isoflavones reduce plasma cholesterol and
atherosclerosis in C57BL/6 mice but not LDL receptor-deficient
mice.
Kirk EA; Sutherland P; Wang SA; Chait A; LeBoeuf RC
Department of Medicine and the Nutritional Sciences Program,
University of Washington, Seattle, WA 98195, USA.
J Nutr (United States) Jun 1998, 128 (6) p954-9
Susceptibility to atherosclerosis is determined by a
combination of genetic and environmental factors, including
diet. Consumption of diets rich in soy protein has been
claimed to protect against the development of atherosclerosis.
Potential mechanisms include cholesterol lowering, inhibition
of lipoprotein oxidation and inhibition of cell proliferation
by soy proteins or isoflavones, such as genistein , that are
present in soy . This study was designed to determine whether
soy isoflavones confer protection against atherosclerosis in
mice and whether they reduce serum cholesterol levels and
lipoprotein oxidation. C57BL/6 and LDL receptor-deficient
(LDLr-null) mice were fed soy protein-based, high fat diets
with isoflavones present (IF+, 20.85 g/100 g protein, 0.027
g/100 g genistein , 0.009 g/100 g daidzein) or diets from
which isoflavones , and possibly other components, had been
extracted (IF-, 20.0 g/100 g protein, 0.002 g/100 g genistein
, 0.001 g/100 g daidzein). Because LDLr-null mice develop
extensive atherosclerosis and hypercholesterolemia after
minimal time on a high fat diet, they were fed the diets for 6
wk, whereas C57BL/6 mice were fed the diets for 10 wk. Plasma
cholesterol levels did not differ between LDLr-null mice fed
IF- and those fed IF+, but were 30% lower in C57BL/6 mice fed
the IF+ diet than in those fed the IF- diet. Susceptibility of
LDL to oxidative modification, measured as the lag phase of
conjugated diene formation in LDLr-null mice, was not altered
by isoflavone consumption. All LDLr-null mice developed
atherosclerosis, and the presence or deficiency of dietary
isoflavones did not influence atherosclerotic lesion area. In
contrast, atherosclerotic lesion area was significantly
reduced in C57BL/6 mice fed IF+ compared with those fed IF-.
Thus, this study demonstrates that although the
isoflavone-containing diet resulted in a reduction in
cholesterol levels in C57BL/6 mice, it had no effect on
cholesterol levels or on susceptibility of LDL to oxidative
modification in LDLr-null mice. Further, dietary isoflavones
did not protect against the development of atherosclerosis in
LDLr-null mice but did decrease atherosclerosis in C57BL/6
mice. These findings suggest that soy isoflavones might lower
cholesterol levels by increasing LDL receptor activity, and
the reduction in cholesterol may offer some protection against
atherosclerosis.
Evolution of the health benefits of soy
isoflavones
Barnes S.
S. Barnes, Dept. of Pharmacology and Toxicology, University
of Alabama, Birmingham, AL 35294 United States
Proceedings of the Society for Experimental Biology and
Medicine (United States), 1998, 217/3 (386-392)
Soy is a unique dietary source of the isoflavones ,
genistein and daidzein. It has been part of the Southeast
Asian diet for nearly five millenia, whereas consumption of
soy in the United States and Western Europe has been limited
to the 20th century. Heavy consumption of soy in Southeast
Asian populations is associated with reduction in the rates of
certain cancers end cardiovascular disease. Recent
experimental evidence suggests that phytochemicals in soy are
responsible for its beneficial effects, which may also include
prevention of osteoporosis, a hereditary chronic nose bleed
syndrome, and autoimmune diseases. Exposure of soy formula-fed
infants to the potential estrogenizing effects of the
isoflavones is limited by the first pass effect of the liver
following the uptake of isoflavones from the gut. Several
mechanisms of action of isoflavones have been proposed-both
through estrogen-dependent and estrogen-independent
pathways.
Polyphenols produced during red wine ageing.
Brouillard R; George F; Fougerousse A
Laboratoire de Chimie des Polyphenols, Universite Louis
Pasteur, Faculte de Chimie, Strasbourg, France.
Biofactors (Netherlands) 1997, 6 (4) p403-10
Over the past few years, it has been accepted that a
moderate red wine consumption is a factor beneficial to human
health. Indeed, people of France and Italy, the two major
wine-producing European countries, eat a lot of fatty foods
but suffer less from fatal heart strokes than people in
North-America or in the northern regions of Europe, where wine
is not consumed on a regular basis. For a time, ethanol was
thought to be the "good" chemical species hiding behind what
is known as the "French paradox". Researchers now have turned
their investigations towards a family of natural substances
called "polyphenols", which are only found in plants and are
abundant in grapes . It is well known that these molecules
behave as radical scavengers and antioxidants, and it has been
demonstrated that they can protect cholesterol in the LDL
species from oxidation, a process thought to be at the origin
of many fatal heart attacks. However, taken one by one, it
remains difficult to demonstrate which are the best
polyphenols as far as their antioxidant activities are
concerned. The main obstacle in that kind of research is not
the design of the chemical and biological tests themselves,
but surprisingly enough, the limited access to chemically pure
and structurally elucidated polyphenolic compounds. In this
article, particular attention will be paid to polyphenols of
red wine made from Vitis vinifera cultivars. With respect to
the "French paradox", we address the following question: are
wine polyphenolic compounds identical to those found in grapes
(skin, pulp and seed), or are there biochemical modifications
specifically taking place on the native flavonoids when a wine
ages? Indeed, structural changes occur during wine
conservation, and one of the most studied of those changes
concerns red wine colour evolution, called "wine ageing". As a
wine ages, it has been demonstrated that the initially present
grape pigments slowly turn into new more stable red pigments.
That phenomenon goes on for weeks, months and years. Since
grape and wine polyphenols are chemically distinct, their
antioxidant activities cannot be the same. So, eating grapes
might well lead to beneficial effects on human health, due to
the variety and sometimes large amounts of their polyphenolic
content. However, epidemiological surveys have focused on
wines,not on grapes .... (35 Refs.)
Lipemic and lipoproteinemic effects of natural and
synthetic androgens in humans.
Crist DM; Peake GT; Stackpole PJ
Clin Exp Pharmacol Physiol (England) Jul 1986, 13 (7)
p513-8
Testosterone cypionate administration in weight-trained
subjects reduced serum high-density lipoprotein cholesterol
(HDL-C) levels without affecting the total cholesterol
(Total-C)/HDL-C ratio. Nandrolone decanoate administration
also reduced HDL-C levels, but elevated the Total-C/HDL-C
ratio. These findings could not be attributed to changes in
exercise patterns, dietary intake, or alcohol consumption. It
is concluded that the synthetic androgen employed in this
study produced a worsening of potential lipid-related risk
factors for ischemic heart disease and that exogenous
testosterone has a much less pronounced effect on such risk
factors.
Fats in indian diets and their nutritional and
health implications
Ghafoorunissa
National Institute of Nutrition, Indian Council of Medical
Research, Jamai Osmania, Hyderabad 500 007 India
Lipids (USA), 1996, 31/3 Suppl. (S287-S291)
To arrive at fat requirements for Indians, the contribution
of invisible fat should be determined. Total lipids were
extracted from common Indian foods, and their fatty acid
compositions were determined. This data and information on
intake of various foods were used to estimate the contents of
'invisible' fat and fatty acids in Indian diets. Taking into
account World Health Organization (WHO) guidelines and the
invisible fat intake of Indians, recommendations were made for
lower and upper limits of visible fats. In the rural poor, the
'visible'-fat intakes are much lower than estimated minimum
requirements. Therefore, to meet the energy needs of low
income groups, particularly young children, visible-fat
intakes must be increased to recommended levels. The urban
high-income group, however, should reduce dietary fat. Data on
intake of various fatty acids in total diet shows that even
the recommended lower limit of oil can meet linoleic acid
requirements. Intake of alpha-linolenic acid is low, however.
Increase in dietary n-3 polyunsaturated fatty acid (PUFA)
produces hypolipidemic, anti-inflammatory, and antithrombotic
effects. Effects of n-3 PUFA on blood lipids, platelet fatty
acid composition, and platelet aggregation were therefore
investigated in Indian subjects consuming cereal based diets.
Supplementation of fish oils (long-chain n-3 PUFA) as well as
the use of rapeseed oil (alpha-linolenic acid) produced
beneficial effects. Since the requirements of alpha-linolenic
acid and/or long-chain n-3 PUFA are related to linoleic acid
intake, use of more than one oil (correct choice) is
recommended for providing a balanced intake of various fatty
acids. Analysis of Indian food showed that some foods are good
sources of alpha-linolenic acid. Regular consumption of these
foods can also improve the quality of fat in Indian diets.
Nonvegetarians, however, have the choice of eating fish to
accomplish this.
The effects of natural dietary fiber from fruit and
vegetables with oxalate from spinach on plasma minerals,
lipids and other metabolites in men
Schoolfield D.J.; Behall K.M.; Kelsay J.L.; Prather E.S.;
Clark W.M.; Reiser S.; Canary J.J.
Carbohydrate Nutrition Laboratory, Beltsville Human Nutrition
Research Center, ARS, USDA, Beltsville, MD 20705 USA
Nutr. Res. (USA), 1990, 10/4 (367-378)
Diets high in fiber and oxalate may result in decreased
mineral bioavailability. However, increased fiber intake can
reduce risk factors for some diseases. Twelve men were fed
diets containing 25 g or 5 g of neutral detergent fiber with
450 mg/day of oxalic acid for six weeks each in a crossover
design to determine whether plasma minerals and other
metabolites would be affected. High dietary oxalate levels
were fed throughout the study. The fiber sources were fruit
and vegetables or their juices and spinach was the source of
oxalate. Five minerals and cholesterol , triglycerides, uric
acid, glucose and urea nitrogen (BUN) were measured in fasting
plasma and correlated with fecal oxalate, mineral intake and
apparent mineral balance. Fiber level had no effect on the
plasma constituents. Plasma inorganic phosphorus (P(i))
decreased (p = 0.002), while BUN, calcium and copper increased
(p < 0.010), (p = 0.004), (p = 0.011) with time. BUN and
P(i) changes which occurred may have been related to ingestion
of high levels of oxalate for eighty-four days.
Medical nutrition therapy lowers serum cholesterol
and saves medication costs in men with
hypercholesterolemia.
Sikand G; Kashyap ML; Yang I
Division of Cardiology, University of California-Irvine,
Orange 92868-3298, USA.
J Am Diet Assoc (United States) Aug 1998, 98 (8) p889-94;
quiz 895-6
This study was designed to evaluate whether medical
nutrition therapy administered by registered dietitians could
lead to a beneficial clinical and cost outcome in men with
hypercholesterolemia. Ninety-five subjects participating in a
cholesterol -lowering drug study took part in an 8-week
nutrition intervention program before initiating treatment
with a cholesterol -lowering medication, Patient records were
reviewed via a retrospective chart review to determine plasma
lipid levels at the beginning and end of the program and the
number and length of sessions with a dietitian. Complete
information was available for 74 subjects aged 60.8 n+/- 9.8
years (mean +/- SD). Medical nutrition therapy lowered total
serum cholesterol levels 13% (P < .001), low-density
lipoprotein cholesterol (LDL-C) 15% (P < .0001),
triglyceride 11% (P < .05), and high-density lipoprotein-
cholesterol (HDL-C) 4% (P < .05). Total dietitian
intervention time was 144 +/- 21 minutes (range = 120 to 180
minutes) in 2.8 +/- 0.7 sessions (range = 2 to 4) during 6.81
+/- 0.7 weeks of medical nutrition therapy (range = 6 to 8
weeks). Analysis of covariance was conducted to examine
whether mean change in LDL-C differed by number of dietitian
visits. Results showed a marginal difference between the
number of dietitian visits and change in LDL-C (f = 2.6, P
< .084). However, the magnitude of LDL-C reduction was
significantly higher with 4 dietitian visits (180 minutes)
than with 2 visits (120 minutes) (21.9% vs 12.1%; P = .027).
Lipid drug eligibility was obviated in 34 of 67 (51%) subjects
per the National Cholesterol Treatment Program guidelines
algorithm. The estimated annualized cost savings from the
avoidance of lipid medications was $60,561.68. Therefore, we
conclude that 3 or 4 individualized dietitian visits of 50
minutes each over 7 weeks are associated with a significant
serum cholesterol reduction and a savings of health care
dollars.
Perspectives in the treatment of dyslipidemias in
the prevention of coronary heart disease.
Borgia MC; Medici F
Universita Degli Studi di Roma La Sapienza, Italy.
Angiology (United States) May 1998, 49 (5)
p339-48
In this review the indications for the available treatments
for dyslipidemias in the prevention of coronary heart disease
(CHD) are considered, and their efficacy according to the
latest studies is analyzed. As data sources the authors used
the main multicenter studies performed in the last twenty
years to evaluate primary and secondary prevention of CHD by
correcting dyslipidemias as well as the results of
meta-analyses of these studies. All treatments considered were
found effective in preventing CHD morbidity and mortality to
some extent. In particular, the combination of diet with
niacin or hydroxymethylglutaryl coenzyme A (HMG CoA) reductase
inhibitors seems to give the best results. These drugs induce
a marked reduction of total and low-density lipoprotein (LDL)
cholesterol and an increase of high-density lipoprotein (HDL)
cholesterol concentrations. The use of diet, niacin , and HMG
CoA reductase inhibitors reduces total as well as specific
mortality. Treatment of dyslipidemia to prevent CHD depends on
the pattern and severity of dyslipidemia, the presence of
overt CHD, and the patient's response to diet. Pharmacologic
treatment should be started only after dietary modifications
have been tried and must be combined with diet. Drug side
effects must also be considered, for they may affect patient
compliance. High levels of total and LDL and low levels of HDL
cholesterol are major risk factors for coronary
atherosclerosis. Correcting lipid abnormalities can reduce the
risk of development or progression of CHD. Diet and drugs are
the main instruments available to normalize lipid levels. The
choice of drug to combine with diet must be based on its
specific effects on lipid metabolism, side effects, and
efficacy in reducing CHD. (77 Refs.)
Effects of crystalline nicotinic acid-induced
hepatic dysfunction on serum low-density lipoprotein
cholesterol and lecithin cholesteryl acyl transferase.
Tato F; Vega GL; Grundy SM
Department of Clinical Nutrition of the University of Texas
Southwestern Medical Center and The Veterans Affairs Medical
Center at Dallas, 75235-9052, USA.
Am J Cardiol (United States) Mar 15 1998, 81 (6)
p805-7
Marked lowering of plasma total and low-density lipoprotein
cholesterol levels that occur during treatment of dyslipidemia
with pharmacologic doses of nicotinic acid result from
hepatotoxicity. Therefore, a marked reduction in low-density
lipoprotein may suggest generalized liver toxicity and drug
treatment should be discontinued.
A randomized trial of the effects of atorvastatin
and niacin in patients with combined hyperlipidemia or
isolated hypertriglyceridemia. Collaborative Atorvastatin
Study Group.
McKenney JM; McCormick LS; Weiss S; Koren M; Kafonek S; Black
DM
Virginia Commonwealth University, Richmond, USA.
Am J Med (United States) Feb 1998, 104 (2)
p137-43
BACKGROUND: To assess the lipid-lowering effects and safety
of atorvastatin and niacin in patients with combined
hyperlipidemia or isolated hypertriglyceridemia.
METHODS: We performed a randomized, open-label,
parallel-design, active-controlled, study in eight centers in
the United States. We enrolled 108 patients with total
cholesterol (TC) of > or =200 mg/dL, serum triglycerides
(TG) > or =200 and < or =800 mg/dL, and apolipoprotein B
(apo B) > or =110 mg/dL. Patients were randomly assigned to
receive atorvastatin 10 mg once daily (n=55) or
immediate-release niacin 1 g three times daily for 12 weeks
(n=53). Patients were stratified based on low-density
lipoprotein cholesterol (LDL-C): Patients with LDL-C > or
=135 mg/dL were considered to have combined hyperlipidemia and
patients with LDL-C <135 mg/dL were considered to have
isolated hypertriglyceridemia. The primary outcome measure was
percent change from baseline in LDL-C. Other lipid levels were
evaluated as secondary parameters.
RESULTS: Atorvastatin reduced LDL-C 30% and TC 26% from
baseline, and increased high-density lipoprotein cholesterol
(HDL-C) 4%. Total TG were reduced 17%. Niacin reduced LDL-C
2%, TC 7%, increased HDL-C 25%, and reduced total TG 29% from
baseline. There was a significant difference in LDL-C
reduction , the primary efficacy parameter, between the two
treatment groups (P <0.05, favoring atorvastatin), as well
as a significant difference in the improvement in HDL-C (P
<0.05, favoring niacin). The effect of atorvastatin was
relatively consistent between patients with combined
hyperlipidemia and isolated hypertriglyceridemia, whereas
there was more variability between these strata in the niacin
treatment group. Atorvastatin was better tolerated than niacin
.
CONCLUSION: Atorvastatin may allow patients with combined
hyperlipidemia to be treated with monotherapy and offers an
efficacious and well-tolerated alternative to niacin for the
treatment of patients with isolated hypertriglyceridemia.
Use of niacin , statins, and resins in patients
with combined hyperlipidemia.
Brown BG; Zambon A; Poulin D; Rocha A; Maher VM; Davis JW;
Albers JJ; Brunzell JD
Department of Medicine, University of Washington School of
Medicine, Seattle 98195, USA.
Am J Cardiol (United States) Feb 26 1998, 81 (4A)
p52B-59B
Patients in the original Familial Atherosclerosis Treatment
Study (FATS) cohort were subgrouped into those with
triglyceride levels < or = 120 mg/dL (n = 26) and those
with triglyceride levels > or = 190 mg/dL (n = 40). Their
therapeutic responses to niacin plus colestipol, lovastatin
plus colestipol, colestipol alone, or placebo were determined.
Therapeutic response was also determined in the same 2
triglyceride subgroups (n = 12 and n = 27, respectively) of
patients selected for low levels of high-density lipoprotein
(HDL) cholesterol and coronary artery disease. These
triglyceride criteria were chosen to identify patient
subgroups with high likelihood of "pattern A" (normal-size
low-density lipoprotein [LDL] particles and triglyceride <
or = 120 mg/dL) or "pattern B" (small dense LDL and
triglyceride > or = 190 mg/dL). Our findings in these small
patient subgroups are consistent with the emerging
understanding that coronary artery disease patients presenting
with high triglyceride levels have lower HDL-C, smaller less
buoyant LDL-C, and greater very low-density lipoprotein (VLDL)
cholesterol and VLDL apolipoprotein B, and are more responsive
to therapy as assessed by an increase in HDL-C and reduction
in triglycerides, VLDL-C, and VLDL apolipoprotein B. In the
FATS high-triglyceride subgroup with these characteristics, a
tendency toward greater therapeutic improvement in coronary
stenosis severity was observed among those treated with either
of the 2 forms of intensive cholesterol -lowering therapy.
This improvement is associated with therapeutic reduction of
LDL-C and elevation of HDL-C, but also appears to be
associated with drug-induced improvement in LDL buoyancy. (20
Refs.)
Triglyceride as a risk factor for coronary artery
disease
Gotto A.M. Jr.
Dr. A.M. Gotto Jr., Weill Medical College, Olin Hall, 445 E.
69th Street, New York, NY 10021 United States
American Journal of Cardiology (United States), 1998, 82/9 A
(22Q-25Q)
The data for an independent association between
triglyceride concentrations and risk for coronary artery
disease (CAD) are equivocal, unlike the data for low-density
lipoprotein (LDL) cholesterol and high- density lipoprotein
(HDL) cholesterol , which show strong, consistent, and
opposing correlations with CAD risk. There is some evidence
for triglyceride as an independent risk factor in certain
subgroups, for example, women 50-69 years of age (Framingham
Heart Study) and in patients with noninsulin- dependent
diabetes. However, the evidence is stronger for triglyceride
as a synergistic CAD risk factor. For example, patients with
the 'lipid triad' of high LDL cholesterol , low HDL
cholesterol , and high triglyceride accounted for most of the
event reduction with lipid-lowering therapy in the Helsinki
Heart Study. An important confounder of the correlation
between triglyceride and CAD risk is the heterogeneity of
triglyceride, rich lipoproteins: the larger triglyceride-rich
particles are thought not to be associated with CAD risk,
whereas the smaller (and denser) particles are believed to be
atherogenic. At present, measurement of fasting triglyceride
levels and triglyceride assessment in conjunction with LDL
cholesterol and HDL cholesterol concentrations are the most
practical methods of evaluating hypertriglyceridemia in CAD
risk, although postprandial lipemia may prove a better
indicator of atherogenicity. Management of
hypertriglyceridemia should initially focus on
nonpharmacologic therapy (i.e., diet, exercise, weight
control, and alcohol reduction). In diabetic patients,
meticulous glycemic control is also important. However, if
this approach proves inadequate, there are several
pharmacologic options. Fibrates may be effective in decreasing
triglyceride and increasing HDL cholesterol . Nicotinic acid
(niacin) has been shown to decrease triglyceride, increase HDL
cholesterol , lower LDL cholesterol , and decrease
lipoprotein(a); it also decreases fibrinogen. The statins
appear to be effective in decreasing triglyceride and LDL
cholesterol in hypertriglyceridemia; however, they do not
normalize metabolism of apolipoprotein B, and HDL cholesterol
may remain low. Therefore, combination with a fibrate or
niacin may be appropriate. Attention to hypertriglyceridemia
with respect to increased CAD risk represents an important
step in assessing global risk for CAD development.
The antiatherogenic role of high-density
lipoprotein cholesterol
Kwiterovich P.O. Jr.
Dr. P.O. Kwiterovich Jr., Johns Hopkins Hospital, CMSC 604,
600 North Wolfe Street, Baltimore, MD 21287-3654 United
States
American Journal of Cardiology (United States), 1998, 82/9 A
(13Q-21Q)
Landmark clinical studies in the past 5 years that
demonstrated diminished mortality and first coronary events
following lowering of low- density lipoprotein (LDL)
cholesterol stimulated considerable interest in the medical
community. Yet, high-density lipoprotein (HDL) cholesterol ,
which transports circulating cholesterol to the liver for
clearance, clearly also exerts antiatherogenic effects. The
Framingham Heart Study produced compelling epidemiologic
evidence indicating that a low level of HDL cholesterol was an
independent predictor of coronary artery disease (CAD).
Emerging experimental and clinical findings are, collectively,
now furnishing a solid scientific foundation for this
relation. First, the reverse cholesterol transport
pathway-including the roles of nascent (pre-beta) HDL,
apolipoprotein A-I, lecithin-cholesterol acyltransferase
(LCAT), cholesteryl ester transport protein, and hepatic
uptake of cholesteryl ester from HDL by liver-is better
understood. For example, the identification of a hepatic HDL
receptor, SR-BI, suggests a mechanism of delivery of
cholesteryl ester to liver that differs from the
receptor-mediated uptake of LDL. Second, apolipoprotein A-I,
the major protein component of HDL, and 2 enzymes on HDL,
paraoxonase and platelet-activating factor acetylhydrolase
appear to diminish the formation of the highly atherogenic
oxidized LDL. Third, lower levels of HDL cholesterol are
associated in a dose-response fashion with the severity and
number of angiographically documented atherosclerotic coronary
arteries. Fourth, low HDL cholesterol predicts total mortality
in patients with CAD and desirable total cholesterol levels
(<200 mg/dL). Fifth, low HDL cholesterol concentrations
appear to be associated with increased rates of restenosis
after percutaneous transluminal coronary angioplasty. In terms
of elevating HDL cholesterol , cessation of cigarette smoking,
reduction to ideal body weight, and regular aerobic exercise
all appear important. Most medications used to treat
dyslipidemias will raise HDL cholesterol levels modestly;
however, niacin appears to have the greatest potential to do
so, and can increase HDL cholesterol up to 30%. Recognizing
these data, the most recent report of the National Cholesterol
Education Program identified low HDL cholesterol as a CAD risk
factor and recommended that all healthy adults be screened for
both total cholesterol and HDL cholesterol levels.
Atorvastatin in the treatment of primary
hypercholesterolemia and mixed dyslipidemias
Yee H.S.; Fong N.T.
H.S. Yee, Pharmacy Service, Dept. of Veterans Affairs Med.
Ctr., 4150 Clement St., San Francisco, CA 94121 United
States
Annals of Pharmacotherapy (United States), 1998, 32/10
(1030-1043)
OBJECTIVE: To review the efficacy and safety of
atorvastatin in the treatment of dyslipidemias.
DATA SOURCES: A MEDLINE search (January 1960- April 1998),
Current Contents search, additional references listed in
articles, and unpublished data obtained from the manufacturer
were used to identify data from scientific literature. Studies
evaluating atorvastatin (i.e., abstracts, clinical trials,
proceedings, data on file with the manufacturer) were
considered for inclusion.
STUDY SELECTION: English- language literature was reviewed
to evaluate the pharmacology, pharmacokinetics, therapeutic
use, and adverse effects of atorvastatin. Additional relevant
citations were used in the introductory material and
discussion.
DATA EXTRACTION: Open and controlled animal and human
clinical studies published in English-language literature were
reviewed and evaluated. Clinical trials selected for inclusion
were limited to those in human subjects and included data from
animals if human data were not available.
DATA SYNTHESIS: Atorvastatin is a recent
hydroxymethylglutaryl-coenzyme A (HMG-CoA) reductase inhibitor
for the treatment of primary hypercholesterolemia, mixed
dyslipidemias, and homozygous familial hypercholesterolemia.
In patients who have not met the low-density lipoprotein
cholesterol (LDL-C) goal as recommended by the National
Cholesterol Education Program Adult Treatment Panel II
guidelines, atorvastatin 10-80 mg/d may be used as monotherapy
or as an adjunct to other lipid-lowering agents and dietary
modifications. In placebo-controlled clinical trials,
atorvastatin 10-80 mg/d lowered LDL-C by 35-61% and
triglyceride (TG) concentrations by 14-45%. In comparative
trials, atorvastatin 10-80 mg/d showed a greater reduction of
serum total cholesterol (TC), LDL-C, TG concentrations, and
apolipoprotein B-100 (apo B) compared with pravastatin,
simvastatin, or lovastatin. In comparison, currently available
HMG-CoA reductase inhibitors (lovastatin, simvastatin,
pravastatin, fluvastatin, cerivastatin) lower LDL-C
concentrations by approximately 20- 40% and TG concentrations
by approximately 10-30%. In pooled placebo- controlled
clinical trials of up to a duration of 52 weeks, atorvastatin
in dosages up to 80 mg/d appeared to be well tolerated. The
most common adverse effect of atorvastatin was
gastrointestinal upset. The incidence of elevated serum
hepatic transaminases may be greater at higher dosages of
atorvastatin. The risk of myopathy and/or rhabdomyolysis is
increased when an HMG-CoA reductase inhibitor is taken
concomitantly with cyclosporine, gemfibrozil, niacin ,
erythromycin, or azole antifungals.
CONCLUSIONS: Atorvastatin appears to reduce TC, LDL-C, TG
concentrations, and apo B to a greater extent than do
currently available HMG-CoA reductase inhibitors. Atorvastatin
may be preferred in patients requiring greater than a 30%
reduction in LDL-C or in patients with both elevated LDL-C and
TG concentrations, which may obviate the need for combination
lipid-lowering therapy. Adverse effects of atorvastatin appear
to be similar to those of other HMG-CoA reductase inhibitors
and should be routinely monitored. Long-term safety data
(>1 y) on atorvastatin compared with other HMG-CoA
reductase inhibitors are still needed. Cost-effectiveness
studies comparing atorvastatin with other HMG-CoA reductase
inhibitors remain a subject for further investigation.
Published clinical studies evaluating the impact of
atorvastatin on cardiovascular morbidity and mortality are
still needed. Additionally, clinical studies evaluating the
impact of lipid-lowering therapy in a larger number of women,
the elderly (>70 y), and patients with diabetes for
treatment of primary and secondary prevention of coronary
heart disease are needed.
Atorvastatin: A potent new HMG-CoA reductase
inhibitor
Hilleman D.E.; Seyedroubari A.
Dr. D.E. Hilleman, Department of Pharmacy Practice, Creighton
University, Sch. Pharm./Allied Hlth. Professions, 2500
California Plaza, Omaha, NE 68178 United States
Cardiovascular Reviews and Reports (United States), 1998,
19/5 (32-48)
Atorvastatin is the fifth HMG-CoA reductase inhibitor
approved for use in the U.S. The mechanism of action of
atorvastatin appears to be similar to other agents in the
class. Atorvastatin is metabolized by cytochrome P450 3A4 to
several active metabolites. Approximately 70% of the lipid
lowering effect of atorvastatin is attributed to its
metabolites. Atorvastatin's efficacy is greater than that of
other available HMG-CoA reductase inhibitors. At 10 mg/day,
atorvastatin reduces LDL cholesterol by 39% and triglycerides
by 19%. At the highest FDA approved dose of 80 mg/day,
atorvastatin reduces LDL cholesterol by 60% and triglycerides
by 37%. Atorvastatin 10 mg/day produces LDL cholesterol
reductions that are similar to or greater than the LDL
cholesterol reductions achieved with all doses up to 40 mg/day
with the other HMG-CoA reductase inhibitors. Atorvastatin is
associated with a very low incidence of dose-limiting side
effects with a discontinuation rate of less than 2%. The most
common side effects are constipation, flatulence, dyspepsia,
and abdominal pain. In comparative trials against other
HMG-CoA reductase inhibitors, no significant differences in
the incidence of side effects were observed. As with other
HMG-CoA reductase inhibitors, combined use of atorvastatin
with erythromycin, cyclosporin, fibric acid derivatives,
niacin , and azole antifungals increases the risk of myopathy.
Atorvastatin represents a highly effective HMG-CoA reductase
inhibitor that produces greater reductions in LDL cholesterol
and triglycerides than other currently available agents in
this class. Based on NCEP treatment guidelines in which
predetermined LDL cholesterol levels are the goal of therapy,
atorvastatin appears to fill a major void that exists with
current therapy. For patients requiring a 40% or greater
reduction in LDL cholesterol , atorvastatin is the only agent
capable of such reductions. The major unresolved issue with
atorvastatin is its unknown impact on cardiovascular morbidity
and mortality.
Hypocoagulant and lipid-lowering effects of dietary
n-3 polyunsaturated fatty acids with unchanged platelet
activation in rats.
Nieuwenhuys CM; Beguin S; Offermans RF; Emeis JJ; Hornstra G;
Heemskerk JW
Department of Human Biology, University of Maastricht, The
Netherlands.
C.Nieuwenhuys@hb.unimaas.nl
Arterioscler Thromb Vasc Biol (United States) Sep 1998, 18
(9) p1480-9
We investigated the effects of dietary polyunsaturated
fatty acids (PUFAs) on blood lipids and processes that
determine hemostatic potential: platelet activation,
coagulation, and fibrinolysis. For 8 to 10 weeks, Wistar rats
were fed a high-fat diet containing various amounts (2% to
16%) of n-3 PUFAs derived from fish oil (FO) or a diet
enriched in n-6 PUFAs from sunflower seed oil (SO). Only the
FO diets caused a reduction in mean platelet volume, platelet
arachidonate level, and formation of thromboxane B2 by
activated platelets, but neither of the diets had a measurable
effect on platelet activation. The FO-rich diets decreased the
plasma concentrations of triglycerides and cholesterol ,
whereas the SO diet reduced triglycerides only. Parameters of
fibrinolysis and standard coagulation times, ie, activated
partial thromboplastin time and prothrombin time, were only
marginally influenced by these diets. In contrast, dietary FO,
but not SO, led to decreased levels of the vitamin K-dependent
coagulation factors prothrombin and factor VII, while the
level of antithrombin III was unchanged. The endogenous
thrombin potential (ETP) was measured with an assay developed
to detect the hypocoagulable state of plasma. After activation
with tissue factor and phospholipids, the ETP was reduced by
23% or more in plasma from animals fed a diet with >4% FO.
No significant effect of the SO diet on ETP was observed.
Control experiments with plasma from warfarin-treated rats
indicated that the ETP was more sensitive to changes in
prothrombin concentration than in factor VII concentration.
Taken together, these results indicate that in rats, prolonged
administration of n-3 but not n-6 PUFAs can lead to a
hypocoagulable state of plasma through a reduced capacity of
vitamin K-dependent thrombin generation, with unchanged
thrombin inactivation by antithrombin III.
Effects of dietary fish oil on serum lipids and
VLDL kinetics in hyperlipidemic apolipoprotein E*3-Leiden
transgenic mice.
van Vlijmen BJ; Mensink RP; van 't Hof HB; Offermans RF;
Hofker MH; Havekes LM
TNO Prevention and Health, Gaubius Laboratory, Leiden, The
Netherlands.
J Lipid Res (United States) Jun 1998, 39 (6)
p1181-8
Studying the effects of dietary fish oil on VLDL metabolism
in humans is subject to both large intra- and interindividual
variability. In the present study we therefore used
hyperlipidemic apolipoprotein (APO) E*3-Leiden mice, which
have impaired chylomicron and very low density lipoprotein
(VLDL) remnant metabolism, to study the effects of dietary
fish oil on serum lipids and VLDL kinetics under highly
standardized conditions. For this, female APOE*3-Leiden mice
were fed a fat- and cholesterol -containing diet supplemented
with either 0, 3 or 6% w/w (i.e. 0, 6, or 12% of total energy)
of fish oil . Fish oil -fed mice showed a significant
dose-dependent decrease in serum cholesterol (up to -43%) and
triglyceride levels (up to -60%), mainly due to a reduction of
VLDL (-80%). LDL and HDL cholesterol levels were not affected
by fish oil feeding. VLDL-apoB kinetic studies showed that
fish oil feeding resulted in a significant 2-fold increase in
VLDL-apoB fractional catabolic rate (FCR). Hepatic VLDL-apoB
production was, however, not affected by fish oil feeding.
VLDL-triglyceride turnover studies revealed that fish oil
significantly decreased hepatic VLDL-triglyceride production
rate (-60%). A significant increase in VLDL-triglyceride FCR
was observed (+70%), which was not related to increased
lipolytic activity. We conclude that APOE*3-Leiden mice are
highly responsive to dietary fish oil . The observed strong
reduction in serum very low density lipoprotein (VLDL) is
primarily due to an effect of fish oil to decrease hepatic
VLDL triglyceride production rate and to increase VLDL-apoB
fractional catabolic rate.
Effect of fish - oil -enriched margarine on plasma
lipids, low-density-lipoprotein particle composition, size,
and susceptibility to oxidation.
Sorensen NS; Marckmann P; Hoy CE; van Duyvenvoorde W; Princen
HM
Department of Biochemistry and Nutrition, Technical
University of Denmark, Lyngby. ninas@mimer.be.dtu.dk
Am J Clin Nutr (United States) Aug 1998, 68 (2)
p235-41
We investigated the effect of incorporating n-3
polyunsaturated fatty acids (PUFAs) into the diet on the
lipid-class composition of LDLs, their size, and their
susceptibility to oxidation. Forty-seven healthy volunteers
incorporated 30 g sunflower-oil (SO) margarine/d into their
habitual diet during a 3-wk run-in period and then used either
SO or a fish -oil -enriched sunflower oil (FO) margarine for
the following 4 wk. Plasma concentrations of total cholesterol
, triacylglycerols, HDL cholesterol , LDL cholesterol , and
apolipoproteins A-I and B did not differ significantly between
the groups during intervention. The FO margarine increased the
concentration of n-3 very-long-chain PUFAs in the LDL
particles, showing 93% (P < or = 0.0001), 8% (P = 0.05),
and 35% (P = < 0.0001) increases in eicosapentaenoic acid,
docosapentaenoic acid, and docosahexaenoic acid, respectively,
in the FO group compared with 3%, 7%, and 7%, respectively, in
the SO group during the intervention. The cholesterol content
of the LDL particles increased in the FO group [total
cholesterol : 6% (P = 0.008); cholesterol ester: 12% (P =
0.014)], although it was not significantly different from that
in the control group, whereas the other lipid classes and the
size of the LDL particles remained unchanged in both groups. A
reduction in the alpha-tocopherol content in LDL (6%, P =
0.005) was observed in the FO group. Ex vivo oxidation of LDL
induced with Cu2+ showed a significantly reduced lag time
(from 91 to 86 min, P = 0.003) and lower maximum rate of
oxidation (from 10.5 to 10.2 nmol x mg(-1) x min(-1), P =
0.003) after intake of the FO margarine. The results indicate
that consumption of the FO compared with the SO margarine had
no effect on LDL size and lipid composition and led to minor
changes in LDL a-tocopherol content and oxidation
resistance.
Abnormal content of n-6 and n-3 long-chain
unsaturated fatty acids in the phosphoglycerides and
cholesterol esters of parahippocampal cortex from Alzheimer's
disease patients and its relationship to acetyl CoA
content.
Corrigan FM; Horrobin DF; Skinner ER; Besson JA; Cooper
MB
Argyll and Bute Hospital, Lochgilphead, UK.
Int J Biochem Cell Biol (England) Feb 1998, 30 (2)
p197-207
The long-chain fatty acid composition of cholesterol
esters, phosphatidylcholine (PC), phosphatidylethanolamine
(PE), phosphatidylserine (PS) and phosphatidylinositol (PI)
from parahippocampal cortex of Alzheimer's disease (AD)
patients and control subjects was examined. In general the PC
fraction contained less polyunsaturated long-chain fatty acids
than did PE, PS or PI. Of the n-6 polyunsaturated long-chain
fatty acids, PI contained the greatest incorporation of these
acids followed by PE. There were significant differences
between controls and AD patients in total n-6 EFAs.
Arachidonic acid (C20:4n-6) was the predominant fatty acid of
this family found to be present. In AD, PE and PS showed a
deficit of adrenic acid (C22:4n-6) content and PE also
contained less arachidonic acid. In AD subjects, the
cholesterol esters contained significantly less n-3
polyunsaturated fatty acids with, specifically, a reduction in
alpha-linolenic acid. Acetyl CoA content of hippocampal cortex
was greater in AD patients than in control subjects indicating
either an increased extent of oxidative metabolism or a
failure to utilise acetyl CoA for anabolic processes. Abnormal
magnitude of oxidative processes could give rise to the
biosynthesis of PE and PS species containing less n-6
polyunsaturated fatty acids than occurs in control
subjects.
Mediterranean dietary pattern in a randomized
trial: prolonged survival and possible reduced cancer
rate
de Lorgeril M; Salen P; Martin JL; Monjaud I; Boucher P;
Mamelle N
Laboratoire de Physiologie and GIP-Exercice, Centre
Hospitalo-Universitaire de Saint-Etienne and School of
Medicine, France.
Arch Intern Med (United States) Jun 8 1998, 158 (11)
p1181-7
BACKGROUND: The Mediterranean dietary pattern is thought to
reduce the risk of cancer in addition to being
cardioprotective. However, no trial has been conducted so far
to prove this belief.
METHODS: We compared overall survival and newly diagnosed
cancer rate among 605 patients with coronary heart disease
randomized in the Lyon Diet Heart Study and following either a
cardioprotective Mediterranean-type diet or a control diet
close to the step 1 American Heart Association prudent
diet.
RESULTS: During a follow-up of 4 years, there were a total
of 38 deaths (24 in controls vs 14 in the experimental group),
including 25 cardiac deaths (19 vs 6) and 7 cancer deaths (4
vs 3), and 24 cancers (17 vs 7). Exclusion of early cancer
diagnoses (within the first 24 months after entry into the
trial) left a total of 14 cancers (12 vs 2). After adjustment
for age, sex, smoking, leukocyte count, cholesterol level, and
aspirin use, the reduction of risk in experimental subjects
compared with control subjects was 56% (P=.03) for total
deaths, 61% (P=.05) for cancers, and 56% (P=.01) for the
combination of deaths and cancers. The intakes of fruits,
vegetables, and cereals were significantly higher in
experimental subjects, providing larger amounts of fiber and
vitamin C (P<.05). The intakes of cholesterol and saturated
and polyunsaturated fats were lower and those of oleic acid
and omega - 3 fatty acids were higher (P<.001) in
experimental subjects. Plasma levels of vitamins C and E
(P<.05) and omega -3 fatty acids (P<.001), measured 2
months after randomization, were higher and those of omega-6
fatty acids were lower (P<.001) in experimental
subjects.
CONCLUSIONS: This randomized trial suggests that patients
following a cardioprotective Mediterranean diet have a
prolonged survival and may also be protected against cancer.
Further studies are warranted to confirm the data and to
explore the role of the different lipids and fatty acids in
this protection.
Dietary (n-3) and (n-6) polyunsaturated fatty acids
rapidly modify fatty acid composition and insulin effects in
rat adipocytes.
Fickova M; Hubert P; Cremel G; Leray C
Institute of Experimental Endocrinology, Slovak Academy of
Sciences, 83306 Bratislava, Slovakia.
J Nutr (United States) Mar 1998, 128 (3) p512-9
The influence of dietary (n-3) compared with (n-6)
polyunsatured fatty acids (PUFA) on the lipid composition and
metabolism of adipocytes was evaluated in rats over a period
of 1 week. Isocaloric diets comprised 16.3 g/100 g protein,
53.8 g/100 g carbohydrate and 21.4 g/100 g lipids, the latter
containing either (n-3) PUFA (32.4 mol/100 mol) or (n-6) PUFA
(37.8 mol/100 mol) but having identical contents of saturated,
monounsaturated and total unsaturated fatty acids and
identical polyunsaturated to saturated fatty acid ratios and
double bond indexes. Despite comparable food intake,
significantly smaller body weight increments and adipocyte
size were observed in rats of the (n-3) diet group after
feeding for 1 wk. Rats fed the (n-3) diet also had
significantly lower concentrations of serum triglycerides,
cholesterol and insulin compared with those fed the (n-6)
diet, although levels of serum glucose and free fatty acids
did not differ in the two dietary groups. In the (n-6) diet
group, the (n-6) and (n-3) PUFA contents of plasma
triglycerides, free fatty acids and phospholipids were 30-60%
higher and 60-80% lower, respectively, than in the (n-3) diet
group, whereas adipocyte plasma membrane phospholipids showed
a significantly higher unsaturated to saturated fatty acid
ratio and greater fluidity. Glycerol release in response to
noradrenaline was significantly higher in the adipocytes of
rats fed the (n-3) diet, whereas the antilipolytic effect of
insulin generally did not differ in the two groups. Finally,
insulin stimulated the transport of glucose and its
incorporation into fatty acids to a lesser extent in
adipocytes of (n-3) diet fed rats compared with (n-6) diet fed
rats. This reduction in the metabolic effects of insulin in
rats fed a (n-3) diet for 1 wk could be related to smaller
numbers and a lower binding capacity of the insulin receptors
on adipocytes and/or to a lesser degree of phosphorylation of
the 95 kDa beta subunit of the receptor. In conclusion,
dietary intake for 1 wk of (n-3) rather than (n-6) PUFA is
sufficient to induce significant differences in the lipid
composition and metabolic responses to insulin of rat
adipocytes.
The triphasic effects of exercise on blood
rheology: Which relevance to physiology and
pathophysiology?
Brun J.F.; Khaled S.; Raynaud E.; Bouix D.; Micallef J.P.;
Orsetti A.
J.F. Brun, Svc. d'Explor. Phys. Hormones Metab., CHRU de
Montpellier, F-34059 Montpellier France
Clinical Hemorheology and Microcirculation (United States),
1998, 19/2 (89-104)
The life-extending effects of regular exercise are related
to a decrease in both coronary and peripheral vascular
morbidity, associated with some improvements in cardiovascular
risk factors. A possible link between the beneficial metabolic
and hemodynamic effects of exercise could be blood rheology,
which is markedly affected by exercise. We propose here a
description of the hemorheological effects of exercise as a
triphasic phenomenon. Short-term effects of exercise are an
increase in blood viscosity resulting from both fluid shifts
and alterations of erythrocyte rheologic properties (rigidity
and aggregability). Increased blood lactate, stress, and acute
phase play a role in this process. Middle-term effects of
regular exercise are a reversal of these acute effects with an
increase in blood fluidity, explained by plasma volume
expansion (autohemodilution) that lowers both plasma viscosity
and hematocrit. Long-term effects further improve blood
fluidity, parallel with the classical training-induced
hormonal and metabolic alterations. While body composition,
blood lipid pattern, and fibrinogen improve (thus decreasing
plasma viscosity), erythrocyte metabolic and rheologic
properties are modified, with a reduction in aggregability and
rigidity. On the whole, these improvements reflect a reversal
of the so- called 'insulin-resistance syndrome' induced by a
sedentary lifestyle. Since impaired blood rheology has been
demonstrated to be at risk for vascular diseases, the
hemorheologic effects of exercise can be hypothesized to be a
mechanism (or at least a marker) of risk reversal. This latter
point requires further investigation. The physiological
meaning of the tripbasic pattern of exercise-induced
alterations of blood theology is uncompletely understood, but
increased blood fluidity may improve several steps of oxygen
transfer to muscle, as clearly demonstrated in hypoxic
conditions. Increasing evidence emerges from the literature,
that blood fluidity is a physiological determinant of
fitness.
Hyperlipidemia and diabetes mellitus
O'Brien T.; Nguyen T.T.; Zimmerman B.R.
Dr. T. O'Brien, Div. of Endocrinol., Metabol./Nutri., Mayo
Clinic Rochester, 200 First Street SW, Rochester, MN 55905
United States
Mayo Clinic Proceedings (United States), 1998, 73/10
(969-976)
The increased risk of coronary artery disease in subjects
with diabetes mellitus can be partially explained by the
lipoprotein abnormalities associated with diabetes mellitus.
Hypertriglyceridemia and low levels of high-density
lipoprotein are the most common lipid abnormalities. In type 1
diabetes mellitus, these abnormalities can usually be reversed
with glycemic control. In contrast, in type 2 diabetes
mellitus, although lipid values improve, abnormalities
commonly persist even after optimal glycemic control has been
achieved. Screening for dyslipidemia is recommended in
subjects with diabetes mellitus. A goal of low-density
lipoprotein cholesterol of less than 130 mg/dL and
triglycerides lower than 200 mg/dL should be sought. Several
secondary prevention trials, which included subjects with
diabetes, have demonstrated the effectiveness of lowering
low-density lipoprotein cholesterol in preventing death from
coronary artery disease. The benefit of lowering triglycerides
is less clear. Initial approaches to lowering the levels of
lipids in subjects with diabetes mellitus should include
glycemic control, diet, weight loss, and exercise. When goals
are not met, the most common drugs used are
hydroxymethylglutaryl coenzyme A reductase inhibitors or
fibrates.
Insulin therapy for a non-diabetic patient with
severe hypertriglyceridemia
Jabbar M.A.; Zuhri-Yafi M.I.; Larrea J.
Dr. M.A. Jabbar, Department of Pediatrics, Hurley Medical
Center, 1 Hurley Plaza, Flint, MI 48502 United States
Journal of the American College of Nutrition (United States),
1998, 17/5 (458-461)
Objective: To compare the short and long term effectiveness
of fish oil , insulin, and gemfibrozil in a non-diabetic
patient with severe hypertriglyceridemia.
Method: An adolescent male with hypertriglyceridemia
(triglyceride level 4575 mg/dl) and abdominal pain was treated
with the goal of immediate reduction and maintenance of
triglyceride (TG) level below 1000 mg/dl. Fish oil , insulin
and gemfibrozil were administered sequentially, in separate
time blocks, for a duration of 3, 6, and 6 months,
respectively.
Results: Fish oil took several weeks to lower TG level, and
patient compliance during 3 months of therapy was inadequate.
Insulin was effective in immediately lowering the TG level,
but was unable to maintain the level below 1000 mg/dl.
Gemfibrozil was ineffective in achieving the immediate
reduction of TG level; however, it was adequate in maintaining
the desired level in the long-term and patient compliance was
better than with the fish oil .
Conclusion: In patients with risk of pancreatitis due to
severe hypertriglyceridemia, immediate reduction of the
triglyceride level is achievable by using a single dose of
regular insulin (0.1 unit/kg, subcutaneous) while long-term
maintenance therapy can be provided by gemfibrozil.
Effects of omega- 3 fatty acids and/or antioxidants
on endothelial cell markers
Seljeflot I.; Arnesen H.; Brude I.R.; nenseter M.S.; Drevon
C.A.; Hjermann I.
I. Seljeflot, Medical Outpatient Clinic, Department of
Medicine, Ulleval University Hospital, N-0407 Oslo
Norway
European Journal of Clinical Investigation (United Kingdom),
1998, 28/8 (629-635)
Background. Increased expression of cell adhesion molecules
and increased procoagulant activity of the vascular
endothelium have been postulated to characterize dysfunctional
endothelium. The cellular effects of n-3 fatty acids (n-3 FAs)
and antioxidants are still not clarified.
Methods. In a randomized, factorial two-by-two design
study, we have investigated 41 male smokers with
hyperlipidaemia before and after 6 weeks of supplementation
with either n-3 FAs (4.8 g daily) or placebo with the addition
of antioxidants (1.50 mg of vitamin C, 75 mg of vitamin E and
15 mg of p-carotene daily) or placebo with regard to the
effects on some endothelial cell markers: thrombomodulin
(sTM), von Willebrand factor (vWF), tissue plasminogen
activator antigen (tPAag) and soluble forms of the cell
adhesion molecules E-selectin, P-selectin and vascular cell
adhesion molecule 1 (VCAM-1).
Results. In the n-3 FA group, significant reductions in the
plasma levels of vWF (P = 0.034) and sTM (P<0.001) were
demonstrated compared with placebo, whereas increased levels
were found for E-selectin (P = 0.001) and VCAM-1 (P = 0.010).
In the antioxidant group, no differences in changes were noted
for any of the variables.
Conclusion. The reduction in the levels of sTM and VWF with
n-3 FA supplementation could indicate an improvement with
regard to the haemostatic markers of endothelial dysfunction,
whereas the simultaneous increase in the soluble forms of
E-selectin and VCAM-1 may suggest an adverse effect on the
inflammatory system. The antioxidants seem to be neutral in
their effect on these endothelial cell markers in our study
population of smokers. The interpretation of the soluble forms
of these molecules are, however, still debatable.
Omega-3 ethyl ester concentrate decreases total
apolipoprotein CIII and increases antithrombin III in
postmyocardial infarction patients
Swahn E.; von Schenck H.; Olsson A.G.
Dr. E. Swahn, Department of Cardiology, Institution of
Internal Medicine, University Hospital, S-581 85 Linkoping
Sweden
Clinical Drug Investigation (New Zealand), 1998, 15/6
(473-482)
This study investigated whether an ethyl ester preparation
of fish oil (omega-3) could normalise raised plasma
concentrations of triglycerides, apolipoprotein CIII on
apolipoprotein B-containing particles (LP CIII:B) found in
patients with recent acute myocardial infarction. We also
studied the effect of fish oil on antithrombin III levels. Out
of 75 patients with a plasma triglyceride value less than or
equal to 2.0 mmol/L, 22 normalised their triglycerides during
diet and were therefore not randomised. The remaining patients
were randomly assigned to 12 weeks' treatment with a daily
dose of 4g omega-3 or placebo. Mean plasma triglyceride
concentrations were reduced by 24% from 3.10 plus or minus
1.15 (SD) to 2.53 plus or minus 0.94 mmol/L (p < 0.001) on
omega-3 (p < 0.001 vs placebo). The reduction was due to
decreases in very low density lipoprotein concentrations.
Total apolipoprotein CIII decreased significantly. This was
due to reductions in LP CIII:non B concentrations, but the
ratio LP CIII:non B/LP CIII:B was unaffected because of a
slight insignificant decrease in LP CIII:B. The plasma
triglyceride decreasing effect of omega-3 could therefore not
be due to redistribution of CIII between lipoproteins. Low
density lipoprotein (LDL) cholesterol increased significantly
with omega-3 by 7%, and antithrombin III increased
significantly with fish oil . In conclusion, omega-3 had a
moderate plasma triglyceride lowering effect and increased LDL
cholesterol slightly, while antithrombin III increased in
patients with hypertriglyceridaemia who had recently
experienced a myocardial infarction. Myocardial infarction
starts via a thrombotic process at an atherosclerotic lesion
in a coronary artery. Most patients developing this disease
have an abnormal plasma lipoprotein pattern consisting of
slightly raised triglycerides (TGs), moderately elevated total
cholesterol , and low high density lipoprotein (HDL)
cholesterol values predisposing to atherosclerosis.
Hypertriglyceridaemia may be associated with a greater risk
for thrombosis in postmyocardial infarction patients because
of a reduced fibrinolytic capacity. The dyslipidaemia may also
indicate an unfavourable distribution of plasma lipoprotein
particles in patients with myocardial infarction. Dietary
changes normalise the dyslipidaemia in some patients but are
inadequate in others. In these latter patients pharmacological
lipid-lowering treatment is necessary. The myocardial
infarction patient with an athero-thrombogenic syndrome could
theoretically therefore benefit from a pharmacological agent
acting on both the thrombotic and lipidaemic
pathophysiological pathways. The pharmacological potency of
the omega -3 -fatty acids allows for this possibility. It has
been known since the mid 1970s that omega -3 -fatty acids are
effective in lowering plasma triglyceride concentrations. They
also increase the concentration of HDL cholesterol slightly.
Their effects on cholesterol have varied, with some studies
showing increases and others decreases. These fatty acids also
inhibit platelet aggregation. It was therefore of interest to
expand the experience of this type of treatment to effects on
plasma lipoprotein particle distribution. We also studied
parameters of fibrinolysis since the literature shows
diverging results of omega - 3 - fatty acids on these
parameters. In the present study we tested a new compound,
omega-3, an oil consisting of ethyl esters of eicosapentaenoic
acid (EPA) and docosahexaenoic acid (DHA), with the aim of
normalising dyslipidaemia, and reducing the thrombotic
tendency in a potentially important target population for such
treatment, postmyocardial infarction patients. The high EPA
and DHA concentration in omega-3 made a convenient intake of
only four capsules daily possible. The design of the study
followed the current guidelines for secondary prevention of
ischaemic heart disease.
One-year treatment with ethyl esters of n-3 fatty
acids in patients with hypertriglyceridemia and glucose
intolerance reduced triglyceridemia, total cholesterol and
increased HDL-C without glycemic alterations
Sirtori C.R.; Crepaldi G.; Manzato E.; Mancini M.; Rivellese
A.; Paoletti R.; Pazzucconi F.; Pamparana F.; Stragliotto
E.
C.R. Sirtori, Center E. Grossi Paoletti, University of
Milano, Milan Italy
Atherosclerosis (Ireland), 1998, 137/2 (419-427)
n-3 Fatty acids in the form of ethyl esters (EE) allow
lower daily doses and improved compliance. Administration of
n-3 fatty acids to patients with glucose intolerance has led
to controversial findings, some studies indicating worsening
of the disorder, others no effect, or an improvement. A total
of 935 patients with hypertriglyceridemia, associated with
additional cardiovascular risk factors, i.e. glucose
intolerance, NIDDM and/or arterial hypertension were entered a
double blind (DB) protocol lasting 6 months with n-3 BE versus
placebo, followed by a further 6 months of open study (n =
868) on 2 g a day of n-3 EE. At the end of the DB period,
triglyceridemia in the total group was reduced significantly
more by n-3 EE, without alterations in glycemic parameters. In
the 6 months open follow up, patients on n-3 EE with type IIB
hyperlipoproteinemia showed a significant reduction of total
cholesterol , both in cases with (- 4.15% vs. the 6 month
levels) and without NIDDM (- 3.8%). HDL-cholesterol had an
overall mean rise of 7.4%, maximal in type IV patients with
(+9.1%) and without (+ 10.1%) NIDDM. No alterations in
glycemic parameters were detected in treated patients.
Administration of n-3 EE to patients with hypertriglyceridemia
associated with NIDDM or impaired glucose tolerance appears
safe and effective.
Soluble cell adhesion molecules in
hypertriglyceridemia and potential significance on monocyte
adhesion
Abe Y.; El-Masri B.; Kimball K.T.; Pownall H.; Reilly C.F.;
Osmundsen K.; Smith C.W.; Ballantyne C.M.
Dr. C.M. Ballantyne, Baylor College of Medicine, 6565 Fannin,
MS A-601, Houston, TX 77030 United States
Arteriosclerosis, Thrombosis, and Vascular Biology (United
States), 1998, 18/5 (723-731)
Hypertriglyceridemia may contribute to the development of
atherosclerosis by increasing expression of cell adhesion
molecules (CAMs). Although the cellular expression of CAMs is
difficult to assess clinically, soluble forms of CAMs (sCAMs)
are present in the circulation and may serve as markers for
CAMs. In this study, we examined the association between sCAMs
and other risk factors occurring with hypertriglyceridemia,
the effect of triglyceride reduction on sCAM levels, and the
role of soluble vascular cell adhesion molecule-1 (sVCAM-1) in
monocyte adhesion in vitro. Compared with normal control
subjects (n=20), patients with hypertriglyceridemia and low
HDL (n=39) had significantly increased levels of soluble
intercellular adhesion molecule-1 (sICAM-1) (316plus or
minus28.8 versus 225plus or minus16.6 ng/mL), sVCAM-1 (743plus
or minus52.2 versus 522plus or minus43.6 ng/mL), and soluble
E-selectin (83plus or minus5.9 versus 49three-quarter.6
ng/ml). ANCOVA showed that the higher sCAM levels in patients
occurred independently of diabetes mellitus and other risk
factors. In 27 patients who received purified n-3 fatty acid
(Omacor) 4 g/d for less than or equal to7 months, triglyceride
level was reduced by 47plus or minus4.6%, sICAM-1 level was
reduced by 9plus or minus3.4% (P=.02), and soluble E-selectin
level was reduced by 16plus or minus3.2% (P<.0001), with
the greatest reduction in diabetic patients. These results
support previous in vitro data showing that disorders in
triglyceride and HDL metabolism influence CAM expression and
treatment with fish oils may alter vascular cell activation.
In a parallel-plate flow chamber, recombinant sVCAM-1 at the
concentration seen in patients significantly inhibited
adhesion of monocytes to interleukin-1-stimulated cultured
endothelial cells under conditions of flow by 27.5plus or
minus7.2%. Thus, elevated sCAMs may negatively regulate
monocyte adhesion.
The effects of an omega-3 ethyl ester concentrate
on blood lipid concentrations in patients with
hyperlipidaemia
Borthwick L.
Dr. L. Borthwick, Lister Hospital, Correy's Mill Lane,
Stevenage SG1-4AB United Kingdom
Clinical Drug Investigation (New Zealand), 1998, 15/5
(397-404)
The objective of this study was to investigate the effects
and tolerability of an omega-3 ethyl ester concentrate (Omacor
(R)) on serum lipid concentrations in patients with
hyperlipidaemia. A multicentre, double-blind, randomised,
placebo-controlled trial was performed in the hospital and
general practice setting. 84 patients with hyperlipidaemia
were given a therapeutic lipid-lowering diet for 10 weeks. Of
these, 55 patients were randomised to a 12-week treatment
period. 47 patients completed the study and two patients
withdrew because of adverse events. Randomised patients
received omega-3 ethyl ester concentrate or corn oil
(placebo), both administered at a dose of 2 g twice daily in
soft gelatin capsules. Main outcome measures included changes
in eicosapentaenoic acid (EPA)/ docosahexaenoic acid (DHA)
content of serum phospholipids, total serum triglycerides,
total serum cholesterol , and high density lipoprotein (HDL)
cholesterol between baseline (week 10) and the end of
treatment (week 22). After 12 weeks of treatment, patients
receiving the omega-3 ethyl ester concentrate showed a
significant increase in the EPA/DHA content of serum
phospholipids (p < 0.0001). No significant changes in serum
phospholipids were observed in the patients given placebo. A
mean [standard deviation (SD)] reduction in serum triglyceride
of 28.3 (19.1)% (p = 0.0001) occurred in patients given the
omega-3 ethyl ester concentrate. Patients receiving corn oil
showed a nonsignificant mean (SD) increase in serum
triglyceride of 9.1 (24.8)%. Therefore, a difference between
the groups of 37.4% in favour of active treatment was found (p
< 0.0001). Total serum cholesterol did not change
significantly in either treatment group. Mean (SD) HDL
cholesterol concentrations showed an increase of 0.9 (21.6)%
in patients receiving omega-3 ethyl ester concentrate and 3.6
(24.3)% in the corn-oil group; however, neither increase was
significant. In conclusion, omega-3 ethyl ester concentrate, 4
g/day, produced a significant reduction in mean serum
triglyceride concentration in patients with hyperlipidaemia
and was well tolerated.
On the effect of 2-deuterium- and
2-methyl-eicosapentaenoic acid derivatives on triglycerides,
peroxisomal beta-oxidation and platelet aggregation in
rats
Willumsen N.; Vaagenes H.; Holmsen H.; Berge R.K.
R.K. Berge, Department of Clinical Biology, Division of
Biochemistry, University of Bergen, N-5021 Bergen Norway
Biochimica et Biophysica Acta - Biomembranes (Netherlands),
1998, 1369/2 (193-203)
A series of 2-substituted eicosapentaenoic acid (EPA)
derivatives (as ethyl esters) have been synthesized and
evaluated as hypolipidemic and antithrombotic agents in
feeding experiments in rats. Repeated administration of
purified 2-methyleicosapentaenoic acid and its deuterium
analogues (all as ethyl esters) to rats resulted in a decrease
in plasma triglycerides and high density lipoprotein
cholesterol . The 2-methyl-EPA analogues were, apparently,
four times more potent than EPA in inducing the triglyceride
lowering effect. The 2-deuterium-2-methyl-EPA decreased plasma
cholesterol level to similar 40%. A moderate enlargement of
the liver was observed in 2-methyl-EPA treated rats. This was
accompanied with an acute reduction in the liver content of
triglycerides and a stimulation of peroxisomal beta-oxidation
and fatty acyl-CoA oxidase activity. The results suggest that
the triglyceride-lowering, effect of 2-methyl-EPA may be due
to a reduced supply of fatty acids for hepatic triglyceride
biosynthesis because of increased fatty acid oxidation.
Platelet aggregation with ADP and A23187 was performed ex vivo
in platelet-rich plasma, after administration of different
doses of the EPA-derivatives for five days. EPA and
2,2-dideuterium EPA had no effect on ADP-induced aggregation,
while 2-deuterium-, 2-methyl- and 2-deuterium-2-methyl EPA
produced a biphasic effect, i.e. potentiation and inhibition
at low (250 mg/day kg body weight) and higher doses (600-1300
mg/day kg body weight), respectively. A23187-induced platelet
aggregation was affected in a similar way by feeding the
2-substituted EPA derivatives, except that
2-deuterium-2-methyl EPA had no effect relative to EPA itself
and that the inhibition was far greater than that for
ADP-induced aggregation (similar 100% inhibition with 600 mg
2-methyl-EPA/day kg body weight). The ranking order of the
EPA-derivatives to affect platelet aggregation and to cause
hypolipidemia was different, suggesting different mechanisms.
Our observations suggest that the effects of the EPA
derivatives on platelet aggregation could be related to the
degree of bulkiness around C2 and that an asymmetric
substitution at C2 caused inhibition of platelet aggregation
while a symmetric substitution did not. It is suggested that
the bulky, asymmetric derivatives inhibit platelet aggregation
by altering platelet membrane phospholipid packing.
Effect of garlic (Allium sativum) on blood lipids,
blood sugar, fibrinogen and fibrinolytic activity in patients
with coronary artery disease.
Bordia A; Verma SK; Srivastava KC
Department of Medicine, RNT Medical College, Udaipur,
India.
Prostaglandins Leukot Essent Fatty Acids (Scotland) Apr 1998,
58 (4) p257-63
Thirty patients with coronary artery disease (CAD) were
administered garlic (study group) while another 30 patients
received the placebo (control group). Various risk parameters
were determined at 1.5 and 3 months of garlic administration.
Garlic , administered in a daily dose of 2 x 2 capsules (each
capsule containing ethyl acetate extract from 1 g peeled and
crushed raw garlic), reduced significantly total serum
cholesterol and triglycerides, and increased significantly
HDL- cholesterol and fibrinolytic activity. There was no
effect on the fibrinogen and glucose levels. In vitro effects
of the garlic oil on platelet aggregation (PAg) and eicosanoid
metabolism were examined; it inhibited PAg induced by several
platelet agonists, and also platelet thromboxane formation.
Two important paraffinic polysulphides - diallyl disulphide
(DADS) and diallyl trisulphide (DATS) - derived from garlic
and are usual constituents of garlic oil, showed antiplatelet
activity, and also inhibited platelet thromboxane formation.
In this respect DATS was more potent than DADS. The nature of
inhibition of PAg by DATS was found to be reversible.
Garlic powder and plasma lipids and lipoproteins: a
multicenter, randomized, placebo-controlled trial.
Isaacsohn JL; Moser M; Stein EA; Dudley K; Davey JA; Liskov
E; Black HR
The Christ Hospital Cardiovascular Research Center,
Cincinnati, Ohio, USA.
ejlmarc@aol.com
Arch Intern Med (United States) Jun 8 1998, 158 (11)
p1189-94
BACKGROUND: Garlic powder tablets have been reported to
lower serum cholesterol levels. There is widespread belief
among the general public that garlic powder tablets aid in
controlling cholesterol levels. However, much of the prior
data demonstrating the cholesterol -lowering effect of garlic
tablets involved studies that were inadequately
controlled.
OBJECTIVE: To determine the lipid-lowering effect of garlic
powder tablets in patients with hypercholesterolemia.
METHODS: This was a randomized, double-blind,
placebo-controlled, 12-week, parallel treatment study carried
out in 2 outpatient lipid clinics. Entry into the study after
8 weeks of diet stabilization required a mean low-density
lipoprotein cholesterol level on 2 visits of 4.1 mmol/L (160
mg/dL) or lower and a triglyceride level of 4.0 mmol/L (350
mg/dL) or lower. The active treatment arm received tablets
containing 300 mg of garlic powder (Kwai) 3 times per day,
given with meals (total, 900 mg/d). This is equivalent to
approximately 2.7 g or approximately 1 clove of fresh garlic
per day. The placebo arm received an identical-looking tablet,
also given 3 times per day with meals. The main outcome
measures included levels of total cholesterol , triglycerides,
low-density lipoprotein cholesterol , and high-density
lipoprotein cholesterol after 12 weeks of treatment.
RESULTS: Twenty-eight patients (43% male; mean +/- SD age,
58 +/- 14 years) received garlic powder treatment and 22 (68%
male; mean +/- SD age, 57 +/- 13 years) received placebo
treatment. There were no significant lipid or lipoprotein
changes in either the placebo- or garlic -treated groups and
no significant difference between changes in the
placebo-treated group compared with changes in the garlic
-treated patients.
CONCLUSION: Garlic powder (900 mg/d) treatment for 12 weeks
was ineffective in lowering cholesterol levels in patients
with hypercholesterolemia.
Effect of a garlic oil preparation on serum
lipoproteins and cholesterol metabolism: a randomized
controlled trial.
Berthold HK; Sudhop T; von Bergmann K
Department of Clinical Pharmacology, University of Bonn,
Germany.
berthold@uni-bonn.de
JAMA (United States) Jun 17 1998, 279 (23)
p1900-2
CONTEXT: Garlic -containing drugs have been used in the
treatment of hypercholesterolemia even though their efficacy
is not generally established. Little is known about the
mechanisms of action of the possible effects on cholesterol in
humans.
OBJECTIVE: To estimate the hypocholesterolemic effect of
garlic oil and to investigate the possible mechanism of
action.
DESIGN: Double-blind, randomized, placebo-controlled
trial.
SETTING: Outpatient lipid clinic.
PATIENTS: We investigated 25 patients (mean age, 58 years)
with moderate hypercholesterolemia.
INTERVENTION: Steam-distilled garlic oil preparation (5 mg
twice a day) vs placebo each for 12 weeks with wash-out
periods of 4 weeks.
MAIN OUTCOME MEASURES: Serum lipoprotein concentrations,
cholesterol absorption, and cholesterol synthesis.
RESULTS: Baseline lipoprotein profiles were (mean [SD]):
total cholesterol , 7.53 (0.75) mmol/L (291 [29] mg/dL);
low-density lipoprotein cholesterol (LDL-C), 5.35 (0.78)
mmol/L (207 [30] mg/dL); high-density lipoprotein cholesterol
(HDL-C), 1.50 (0.41) mmol/L (58 [16] mg/dL); and
triglycerides, 1.45 (0.73) mmol/L (127 [64] mg/ dL).
Lipoprotein levels were virtually unchanged at the end of both
treatment periods (mean difference [95% confidence interval]):
total cholesterol , 0.085 (-0.201 to 0.372) mmol/L (3.3 [-7.8
to 14.4] mg/dL), P=.54; LDL-C, 0.001 (-0.242 to 0.245) mmol/L
(0.04 [-9.4 to 9.5] mg/dL), P=.99; HDL-C, 0.050 (-0.028 to
0.128) mmol/L (1.9 [-1.1 to 4.9] mg/dL), P=.20; triglycerides,
0.047 (-0.229 to 0.135) mmol/L (4.2 [-20.3 to 12.0]) mg/dL,
P=.60. Cholesterol absorption (37.5% [10.5%] vs 38.3%
[10.7%0], P=.58), cholesterol synthesis (12.7 [6.5] vs 13.4
[6.6] mg/kg of body weight per day, P=.64), mevalonic acid
excretion (192 [66] vs 187 [66] microg/d, P=.78), and changes
in the ratio of lathosterol to cholesterol in serum (4.4%
[24.3%] vs 10.6% [21.1%], P=.62) were not different in garlic
and placebo treatment.
CONCLUSIONS: The commercial garlic oil preparation
investigated had no influence on serum lipoproteins,
cholesterol absorption, or cholesterol synthesis. Garlic
therapy for treatment of hypercholesterolemia cannot be
recommended on the basis of this study.
[Influence of lifestyle on the use of supplements
in the Brandenburg nutrition and cancer study]
Klipstein-Grobusch K; Kroke A; Voss S; Boeing H
Deutsches Institut fur Ernahrungsforschung, Abteilung
Epidemiologie.
Z Ernahrungswiss (Germany) Mar 1998, 37 (1)
p38-46
Differences in dietary habits and lifestyle factors
associated with a high dietary intake of fruit and vegetables
are discussed and used to explain the disparity between
results of observational epidemiologic studies consistently
showing antioxidative vitamins to exert a protective effect on
chronic diseases, and intervention studies so far not
confirming this association. Within the scope of the
"Brandenburger Ernahrungs- und Krebsstudie", the East German
contribution to the European Prospective Investigation into
Cancer and Nutrition (EPIC), we examined whether study
participants using supplements on a regular basis--minerals,
vitamins, protein formulation, bran/linseed, fiber, yeast or
garlic pills--differed from those who did not report use of
supplements according to selected lifestyle factors and
dietary intake of vitamins, minerals, fiber, cholesterol , and
fat from food. The study sample consisted of 10,522
participants (4,500 men and 6,022 women) aged 35-65 years
enrolled in the cohort from January 1995 to July 1996. Regular
intake of one or more supplements during the past year was
reported by 32.6% of women and 25.5% of men. Vitamin
supplements were used by 18.8% of the women and 15.8% of the
men. Figures for minerals were 14.2% for women and 8.6% for
men, respectively. Garlic pills were taken regularly by 9.7%
of men and 9.3% of women. Prevalence of supplement use was
generally higher in women and was more pronounced in elderly
participants. The most frequently used combinations were
vitamin and mineral supplements, followed by a combination of
garlic and either vitamin or mineral supplements. Increased
use of supplements was significantly associated with higher
level of education attained, regular engagement in sporting
activities, health complaints, and dietary change during the
previous year. No association between use of supplements and
smoking status nor elevated alcohol consumption was observed.
Body mass index above 30 was significantly related to
increased intake of garlic pills, and in women to
significantly increased use of vitamin and mineral
supplements. For both men and women, age-adjusted consumption
of fruit and vegetables and intake of vitamins, minerals, and
fiber from food was higher for participants using mineral but
also vitamin supplements compared to those who did not use
these supplements. For the cohort of the "Brandenburger
Ernahrungs- und Krebsstudie" we observed on the one hand that
age, gender, and health-conscious lifestyle factors were
related to supplement use. On the other hand presence of
subjective health complaints was related to supplement use,
especially for use of vitamins and minerals. Participants, who
regularly consumed minerals and vitamins were also shown to
have a higher intake of foods and nutrients considered to
exert an antioxidative effect.
In vitro effect of garlic powder extract on lipid
content in normal and atherosclerotic human aortic
cells.
Orekhov AN; Tertov VV
Institute of Experimental Cardiology, Russian Academy of
Medical Sciences, Moscow, Russia.
Lipids (United States) Oct 1997, 32 (10)
p1055-60
In the present study, the mechanism of the in vitro effect
of garlic powder extract (GPE) on lipid content of cultured
human aortic cells was investigated. The addition of GPE
abolished atherogenic blood serum-induced accumulation of free
cholesterol , triglycerides, and cholesteryl esters in smooth
muscle cells derived from uninvolved (normal) intima. In cells
isolated from atherosclerotic plaque, GPE lowered these
lipids. GPE inhibited lipid synthesis both in normal and
atherosclerotic cells. It inhibited acyl-CoA:cholesterol
acyltransferase activity that participates in the cholesteryl
ester formation and stimulated cholesteryl ester hydrolase
that degrades cholesteryl esters. This may explain the lipid
reduction caused by GPE in atherosclerotic cells. GPE
inhibited the uptake of modified low density lipoprotein and
degradation of lipoprotein-derived cholesteryl esters, thus
considerably reducing the intracellular accumulation of
cholesteryl esters. This suggests the mechanism responsible
for the prevention of lipid accumulation in aortic cells
caused by atherogenic blood serum.
Modulation of lipid profile by fish oil and garlic
combination.
Morcos NC
Division of Cardiology, University of California, Irvine
92717, USA.
J Natl Med Assoc (United States) Oct 1997, 89 (10)
p673-8
Fish consumption has been shown to influence epidemiology
of heart disease, and garlic has been shown to influence
triglyceride levels. This study was undertaken to evaluate the
effect of fish oil and garlic combinations as a dietary
supplement on the lipid subfractions. Forty consecutive
subjects with lipid profile abnormalities were enrolled in a
single-blind, placebo-controlled crossover study. Each subject
received placebo for 1 month and fish oil (1800 mg of
eicosapentanoic acid [EPA] + 1200 mg of docosahexanoic acid)
with garlic powder (1200 mg) capsules daily for 1 month. Lipid
fractionation was performed prior to study initiation, after
the placebo period, and after the intervention period.
Subjects all had cholesterol levels > 200. Subjects were
instructed to maintain their usual diets. Supplementation for
1 month resulted in an 11% decrease in cholesterol , a 34%
decrease in triglyceride, and a 10% decrease in low-density
lipoprotein (LDL) levels, as well as a 19% decrease in
cholesterol /high-density lipoprotein (HDL) risk. Although not
significant, there was a trend toward increase in HDL. There
was no significant placebo effect. These results suggest that
in addition to the known anticoagulant and antioxidant
properties of both fish oil and garlic , the combination
causes favorable shifts in the lipid subfractions within 1
month. Triglycerides are affected to the largest extent. The
cholesterol lowering and improvement in lipid/HDL risk ratios
suggests that these combinations may have antiatherosclerotic
properties and may protect against the development of coronary
artery disease.
Effect of garlic and fish-oil supplementation on
serum lipid and lipoprotein concentrations in
hypercholesterolemic men
Adler AJ; Holub BJ
Department of Human Biology, University of Guelph,
Canada.
Am J Clin Nutr (United States) Feb 1997, 65 (2)
p445-50
This study examined the effects of garlic and fish-oil
supplementation (alone and in combination) on fasting serum
lipids and lipoproteins in hypercholesterolemic subjects.
After an initial run-in phase, 50 male subjects with moderate
hypercholesterolemia were randomly assigned for 12 wk to one
of four groups: 1) 900 mg garlic placebo/d + 12 g oil
placebo/d; 2) 900 mg garlic /d + 12 g oil placebo/d; 3) 900 mg
garlic placebo/d + 12 g fish oil/d, providing 3.6 g n-3 fatty
acids/d; and 4) 900 mg garlic /d + 12 g fish oil/d. In the
placebo group, mean serum total cholesterol ,
low-density-lipoprotein cholesterol (LDL-C), and
triacylglycerols were not significantly changed in relation to
baseline. Mean group total cholesterol concentrations were
significantly lower with garlic +fish oil (-12.2%) and with
garlic (-11.5%) after 12 wk but not with fish oil alone. Mean
LDL-C concentrations were reduced with garlic +fish oil
(-9.5%) and with garlic (-14.2%) but were raised with fish oil
(+8.5%). Mean triacylglycerol concentrations were reduced with
garlic +fish oil (-34.3%) and fish oil alone (-37.3%). The
garlic groups (with and without fish oil) had significantly
lower ratios of total cholesterol to high-density-lipoprotein
cholesterol (HDL-C) and LDL-C to HDL-C. In summary, garlic
supplementation significantly decreased both total cholesterol
and LDL-C whereas fish-oil supplementation significantly
decreased triacylglycerol concentrations and increased LDL-C
concentrations in hypercholesterolemic men. The combination of
garlic and fish oil reversed the moderate fish-oil-induced
rise in LDL-C. Coadministration of garlic with fish oil was
well-tolerated and had a beneficial effect on serum lipid and
lipoprotein concentrations by providing a combined lowering of
total cholesterol , LDL-C, and triacylglycerol concentrations
as well as the ratios of total cholesterol to HDL-C and LDL-C
to HDL-C.
Garlic powder in the treatment of moderate
hyperlipidaemia: a controlled trial and meta-analysis.
Neil HA; Silagy CA; Lancaster T; Hodgeman J; Vos K; Moore JW;
Jones L; Cahill J; Fowler GH
Department of Public Health and Primary Care, University of
Oxford.
J R Coll Physicians Lond (England) Jul-Aug 1996, 30 (4)
p329-34
OBJECTIVE: To determine the effect of 900 mg/day of dried
garlic powder (standardised to 1.3% allicin) in reducing total
cholesterol .
DESIGN: Double-blind, randomised six-month parallel
trial.
SUBJECTS: 115 individuals with a repeat total cholesterol
concentration of 6.0-8.5 mmol/l and low-density lipoprotein
(LDL) cholesterol of 3.5 mmol/l or above after six weeks of
dietary advice.
INTERVENTION: The active treatment group received dried
garlic tablets (standardised to 1.3% allicin) at a dosage of
300 mg three times daily. The control group received a
matching placebo.
OUTCOME MEASURES: Primary end-point: total cholesterol
concentration; secondary end-points: concentrations of LDL and
high-density lipoprotein cholesterol , apolipoproteins (apo)
A1 and B, and triglycerides.
RESULTS: There were no significant differences between the
groups receiving garlic and placebo in the mean concentrations
of serum lipids, lipoproteins or apo A1 or B, by analysis
either on intention-to-treat or treatment received. In a
meta-analysis which included the results from this trial,
garlic was associated with a mean reduction in total
cholesterol of -0.65 mmol/l (95% confidence intervals: -0.53
to -0.76).
CONCLUSIONS: In this trial, garlic was less effective in
reducing total cholesterol than suggested by previous
meta-analyses. Possible explanations are publication bias,
overestimation of treatment effects in trials with inadequate
concealment of treatment allocation, or a type 2 error. We
conclude that meta-analyses should be interpreted critically
and with particular caution if the constituent trials are
small.
Isolation of cholesteryl ester transfer protein
inhibitors from Panax ginseng roots.
Kwon BM; Nam JY; Lee SH; Jeong TS; Kim YK; Bok SH
Korea Research Institute of Bioscience & Biotechnology,
Taejon.
Chem Pharm Bull (Tokyo) (Japan) Feb 1996, 44 (2)
p444-5
We have isolated cholesteryl ester transfer protein (CETP)
inhibitors from the extract of Korean Panax ginseng C. A.
Meyer roots and identified them as polyacetylene analogs.
These compounds inhibit human CETP with IC50 values of around
20-35 mg/ml.
A double-blind crossover study in moderately
hypercholesterolemic men that compared the effect of aged
garlic extract and placebo administration on blood
lipids.
Steiner M; Khan AH; Holbert D; Lin RI
Memorial Hospital of Rhode Island, Pawtucket, USA
Steiner@Brody.med.ecu.edu
Am J Clin Nutr (United States) Dec 1996, 64 (6)
p866-70
A double-blind crossover study comparing the effect of aged
garlic extract with a placebo on blood lipids was performed in
a group of 41 moderately hypercholesterolemic men [cholesterol
concentrations 5.7-7.5 mmol/L (220-290 mg/dL)]. After a 4-wk
baseline period, during which the subjects were advised to
adhere to a National Cholesterol Education Program Step I
diet, they were started on 7.2 g aged garlic extract per day
or an equivalent amount of placebo as a dietary supplement for
a period of 6 mo, then switched to the other supplement for an
additional 4 mo. Blood lipids, blood counts, thyroid and liver
function measures, body weight, and blood pressure were
followed over the entire study period. The major findings were
a maximal reduction in total serum cholesterol of 6.1% or 7.0%
in comparison with the average concentration during the
placebo administration or baseline evaluation period,
respectively. Low-density-lipoprotein cholesterol was also
decreased by aged garlic extract, 4% when compared with
average baseline values and 4.6% in comparison with placebo
period concentrations. In addition, there was a 5.5% decrease
in systolic blood pressure and a modest reduction of diastolic
blood pressure in response to aged garlic extract. We conclude
that dietary supplementation with aged garlic extract has
beneficial effects on the lipid profile and blood pressure of
moderately hypercholesterolemic subjects.
Perspectives on soy protein as a nonpharmacological
approach for lowering cholesterol.
Goldberg AC
Department of Medicine, Washington University School of
Medicine, St. Louis, MO 63110.
J Nutr (United States) Mar 1995, 125 (3 Suppl)
p675S-678S
Dietary therapy is the first step in the treatment of
hyperlipidemia. However, some patients are unable to lower
their cholesterol concentrations to a desirable range with
diet alone. For primary prevention of coronary artery disease,
physicians and patients often wish to avoid pharmacologic
therapy of elevated cholesterol concentrations. The use of
adjuncts to diet such as soluble fibers, garlic and soy
protein may allow target lipid concentrations to be reached
without the use of drugs. Soy protein incorporated into a
low-fat diet can reduce cholesterol and LDL- cholesterol
concentrations. The main obstacles to greater use of soy
protein in the therapy of hyperlipidemia include lack of
knowledge by physicians and patients of its effects and lack
of availability of easily used products. Although soy products
such as tofu and soymilk are available in many stores,
consumers may be unaware of their presence and uses. Without
the publication of articles in mainstream medical journals on
the cholesterol -lowering effects of soy protein, few
physicians are likely to know of possible uses. Readily
available packaged products, recipes and cookbooks also will
be necessary to make incorporation of soy protein into the
American diet a reality. (30 Refs.)
Consumption of a garlic clove a day could be
beneficial in preventing thrombosis.
Ali M; Thomson M
Department of Biochemistry, Faculty of Science, Kuwait
University, Safat, Kuwait.
Prostaglandins Leukot Essent Fatty Acids (Scotland) Sep 1995,
53 (3) p211-2
The effect of the consumption of a fresh clove of garlic on
platelet thromboxane production was examined. A group of male
volunteers in the age range 40-50 years participated in the
study. Each volunteer consumed one clove (approximately 3 g)
of fresh garlic daily for a period of 16 weeks. Each
participant served as his own control. Thromboxane B2 (TXB2, a
stable metabolite of thromboxane A2), cholesterol and glucose
were determined in serum obtained after blood clotting. After
26 weeks of garlic consumption, there was an approximately 20%
reduction of serum cholesterol and about 80% reduction in
serum thromboxane. No change in the level of serum glucose was
observed. Thus, it appears that small amounts of fresh garlic
consumed over a long period of time may be beneficial in the
prevention of thrombosis.
On the effect of garlic on plasma lipids and
lipoproteins in mild hypercholesterolaemia.
Simons LA; Balasubramaniam S; von Konigsmark M; Parfitt A;
Simons J; Peters W
University of New South Wales Lipid Research Department, St
Vincent's Hospital, Darlinghurst, Australia.
Atherosclerosis (Ireland) Mar 1995, 113 (2)
p219-25
The ingestion of garlic has been reported to have many
cardiovascular effects, including a reduction in plasma
cholesterol concentration and the susceptibility of LDL to
oxidation. A double-blind, placebo-controlled, randomised
crossover study was conducted in subjects with mild to
moderate hypercholesterolaemia who were subject to strict
dietary supervision and assessment. After a baseline dietary
period of 28 days, subjects took Kwai garlic powder tablets
300 mg three times daily or matching placebo for 12 weeks,
followed by 28 days washout, followed by a 12 weeks crossover
on the alternative preparation. In the analysis
hypercholesterolaemia was defined as those subjects in the
range 5.5-8.05 mmol/l. Three subjects were withdrawn, one
allocated to garlic and complaining of garlic body odour, one
using placebo having intercurrent health problems, and one
with a baseline cholesterol below 5.5 mmol/l, yielding
analysable results in 28 subjects. Comparing the period on
garlic with that on placebo, there were no significant
differences in plasma cholesterol , LDL cholesterol , HDL
cholesterol , plasma triglycerides, lipoprotein(a)
concentrations, or blood pressure. Mean LDL cholesterol
concentration was 4.64 +/- 0.52 mmol/l on garlic and 4.60 +/-
0.59 mmol/l on placebo. There was no demonstrable effect of
garlic on oxidisability of LDL, on the ratio of plasma
lathosterol/ cholesterol (a measure of cholesterol synthesis),
nor on LDL receptor expression in lymphocytes. This study
found no demonstrable effect of garlic ingestion on lipids and
lipoproteins.
Direct anti-atherosclerosis-related effects of
garlic.
Orekhov AN; Tertov VV; Sobenin IA; Pivovarova EM
Institute of Experimental Cardiology, Russian Academy of
Medical Sciences, Moscow.
Ann Med (England) Feb 1995, 27 (1) p63-5
Direct anti-atherosclerosis-related effects of garlic were
studied using cell culture. An aqueous extract from garlic
powder (GPE) was added to smooth muscle cells cultured from
atherosclerotic plaques of human aorta. During a 24-hour
incubation, GPE significantly reduced the level of cholesteryl
esters and free cholesterol in these cultured cells and
inhibited their proliferative activity. In addition, GPE
significantly reduced cholesterol accumulation and inhibited
cell proliferation stimulated by blood serum taken from
patients with angiographically assessed coronary
atherosclerosis, i.e. GPE reduced atherogenic manifestations
of patients' serum. Garlic effect on blood atherogenicity of
patients with coronary atherosclerosis has also been studied
ex vivo. Following a 24-hour incubation with cultured cells,
patients' blood serum caused an increase of total cell
cholesterol . Blood serum taken 2 hours after an oral
administration of 300 mg garlic powder tablet caused
substantially less cholesterol accumulation in cultured cells.
This suggests that garlic powder manifests direct
anti-atherogenic-related action not only in vitro but also in
vivo.
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