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
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
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.
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. email@example.com
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
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.
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.
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  mg/dL); low-density lipoprotein cholesterol (LDL-C), 5.35 (0.78) mmol/L (207  mg/dL); high-density lipoprotein cholesterol (HDL-C), 1.50 (0.41) mmol/L (58  mg/dL); and triglycerides, 1.45 (0.73) mmol/L (127  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  vs 187  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.
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
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.
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.