LE Magazine September 2002

Page 1 of 4
Brain function-GPC
Oral choline alfoscerate counteracts
age-dependent loss of mossy fibers in the rat hippocampus.
Mossy fibers represent a major intrahippocampal associative
pathway. They consist of axons of granule cells of the dentate
gyrus and show an age-dependent loss as do the granule cells
of the dentate gyrus. The present study was designed to assess
whether long-term treatment of rats with choline alfoscerate
in their drinking water would be effective in countering the
loss of mossy fibers and of granule cells occurring with
aging. Choline alfoscerate is a precursor in the biosynthesis
of brain phospholipids and increases the bioavailability of
choline in nervous tissue. Male Sprague-Dawley rats of 18
months of age were divided into two groups. One group received
a daily dose of 100 mg/kg choline alfoscerate for six months;
the other group was used as an untreated control.
Twelve-month-old untreated animals were used as a reference
group. The area occupied by mossy fibers, as well as their
density, was significantly reduced in 24-month-old control
rats in comparison with 12-month-old rats. The same is true
for the density granule cells of the dentate gyrus, which was
decreased by about 20% in the oldest animals. In choline
alfoscerate-treated rats both the area occupied by mossy
fibers and their density were significantly higher than in
age-matched controls. Moreover, the number of granule neurons
of the hippocampus was higher by about 7% in choline
alfoscerate-treated than in control 24-month-old rats. The
above data suggest that choline alfoscerate treatment
counteracts some anatomical changes of the rat hippocampus
occurring in old age.
Mech Ageing Dev 1992;66(1):81-91
Long term choline alfoscerate
treatment counters age-dependent microanatomical changes in
rat brain.
1. The density of nerve cells and of silver-gold
impregnated fibres were evaluated in the hippocampus and in
the cerebellar cortex in adult (12-month-old) and old
(24-month-old) Sprague-Dawley rats. 2. The effects of
long-term choline alfoscerate (GFC) treatment (100 mg/kg/day
for six months) on the above parameters were investigated in
old rats. 3. The number of nerve cell profiles and the area
occupied by silver-gold impregnated fibers were decreased both
in the hippocampus and in the cerebellar cortex in old in
comparison with adult rats. 4. GFC treatment countered the
age-dependent reduction of nerve cells and silver-gold
impregnated fibers. The hippocampus was more sensitive than
the cerebellar cortex to the activity of GFC. 5. These results
suggest that GFC treatment is effective in slowing down the
expression of structural changes occurring in aging brain.
Prog Neuropsychopharmacol Biol
Psychiatry 1994 Sep;18(5):915-24
Effect of L-alpha
glycerylphosphorylcholine on muscarinic receptors and membrane
microviscosity of aged rat brain.
1. Old rats showed a significant decrease in the number of
muscarinic M(1) receptors and a significant increase in
membrane microviscosity in the striatum and hippocampus as
compared to young animals. In contrast, no significant changes
in the density of muscarinic M(2) receptors were observed with
aging. 2. Chronic treatment of aged rats with
L-alpha-glycerylphosphorylcholine (L-alpha-GPC) restored the
number of M(1) receptors to levels found in the striatum and
hippocampus from young animals. The same treatment to aged
rats partially restored membrane microviscosity in both
regions studied and hence increased membrane fluidity. 3. None
of the major metabolites of L-alpha-GPC (choline,
glycerophosphate or phosphorylcholine) was able to restore the
number of striatal and hippocampal M(1) sites and membrane
microviscosity of aged rats, neither did any of these
treatments (including treatment with L-alpha-GPC) modify the
level of M(1) receptors and microviscosity values in young
rats.
Prog Neuropsychopharmacol Biol
Psychiatry 1996 Feb;20(2):323-39
Alzheimers disease and senile
dementia: loss of neurons in the basal forebrain.
Recent evidence indicates that the nucleus basalis of
Meynert, a distinct population of basal forebrain neurons, is
a major source of cholinergic innervation of the cerebral
cortex. Postmortem studies have previously demonstrated
profound reduction in the presynaptic markers for cholinergic
neurons in the cortex of patients with Alzheimers
disease and senile dementia of the Alzheimers type. The
results of this study show that neurons of the nucleus basalis
of Meynert undergo a profound (greater than 75%) and selective
degeneration in these patients and provide a pathological
substrate of the cholinergic deficiency in their brains.
Demonstration of selective degeneration of such neurons
represents the first documentation of a loss of a
transmitter-specific neuronal population in a major disorder
of higher cortical function and, as such, points to a critical
subcortical lesion in Alzheimers patients.
Science 1982 Mar
5;215(4537):1237-9
Treatment of cognitive dysfunction
associated with Alzheimers disease with cholinergic
precursors. Ineffective treatments or inappropriate
approaches?
The observations of the loss of cholinergic function in
neocortex and hippocampus in Alzheimers disease (AD)
developed the hypothesis that replacement of cholinergic
function may be of therapeutic benefit to AD patients. The
different approaches proposed or tested included intervention
with acetylcholine (ACh) precursors, stimulation of ACh
release, use of muscarinic or nicotinic receptor agonists and
acetylcholinesterase (AChE) or cholinesterase (ChE)
inhibition. Inhibition of endogenous ACh degradation through
ChE inhibitors and precursor loading were treatments more
largely investigated in clinical trials. Of the numerous
compounds in development for the treatment of AD, AChE and ChE
inhibitors are the most clinically advanced, although clinical
trials conducted to date did not always confirm a significant
benefit of these drugs on all symptom domains of AD. The first
attempts in the treatment of AD with cholinergic precursors
did not confirm a clinical utility of this class of compounds
in well-controlled clinical trials. However, cholinergic
precursors most largely used, such as choline and
phosphatidylcholine (lecithin), were probably not suitable for
enhancing brain levels of ACh. Other phospholipids involved in
choline biosynthetic pathways, such as CDP-choline, choline
alphoscerate and phosphatidylserine clearly enhanced ACh
availability or release and provided a modest improvement of
cognitive dysfunction in AD, these effects being more
pronounced with choline alphoscerate. Although some positive
results cannot be generalized due to the small numbers of
patients studied, they probably would justify reconsideration
of the most promising molecules in larger carefully controlled
trials.
Mech Ageing Dev 2001
Nov;122(16):2025-40
Multicentre study of
l-alpha-glyceryl-phosphorylcholine vs ST200 among patients
with probable senile dementia of Alzheimers type.
A multicentre, randomized, controlled study compared the
efficacy of l-alpha-glyceryl-phosphorylcholine (alpha GPC) and
ST200 (acetyl-l-carnitine) among 126 patients with probable
senile dementia of Alzheimers type (SDAT) of mild to
moderate degree. Efficacy was evaluated by means of
behavioural scales and psychometric tests. The results showed
significant improvements in most neuropsychological parameters
in the alpha GPC recipients. Improvements also occurred in the
ST200 recipients but to a lesser extent. Tolerability was good
in both groups. These positive findings require replication in
larger, double-blind, longitudinal studies coupling clinical
and biological determinations.
Drugs Aging 1993
Mar-Apr;3(2):159-64
Alpha-glycerophosphocholine in the
mental recovery of cerebral ischemic attacks. An Italian
multicenter clinical trial.
The clinical efficacy and the tolerability of
alpha-glycerophosphocholine (alpha-GPC), a drug able to
provide high levels of choline for the nervous cells of the
brain and to protect their cell walls, have been tested in a
clinical open multicenter trial on 2,044 patients suffering
from recent stroke or transient ischemic attacks. alpha-GPC
was administered after the attack at the daily dose of 1000 mg
im for 28 days and orally at the dose of 400 mg tid during the
following five months after the first phase. The evaluation of
the efficacy on the psychic recovery was done by the Mathew
Scale (MS) during the period of im drug administration, and
using the Mini Mental State Test (MMST), the Crichton Rating
Scale (CRS) and the Global Deterioration Scale (GDS) during
the following period of oral administration. The MS mean
increased 15.9 points in 28 days in a statistically
significant way (p < 0.001) from 58.7 to 74.6. At the end
of the five month oral administration, the CRS mean
significantly decreased 4.3 points, from 20.2 to 15.9 (p <
0.001); the MMST mean significantly increased (p < 0.001)
from 21 to 24.3 at the end of the trial, reaching the
normality score at the 3rd month assessment. The
GDS score at the end of the trial corresponded to no
cognitive decline or forgetfulness in 71% of
the patients. Adverse events were complained of by 44 patients
(2.14%); in 14 (0.7%) the investigator preferred to
discontinue therapy. The most frequent complaints were
heartburn (0.7%), nausea-vomit (0.5%), insomnia-excitation
(0.4%), and headache (0.2%). The trial confirms the
therapeutic role of alpha-GPC on the cognitive recovery of
patients with acute stroke or TIA, and the low percentage of
adverse events confirms its excellent tolerability.
Ann N Y Acad Sci 1994 Jun
30;717:253-69
Choline alphoscerate in cognitive
decline and in acute cerebrovascular disease: an analysis of
published clinical data.
This paper has reviewed the documentation on the clinical
efficacy of choline alphoscerate, a cholinergic precursor,
considered as a centrally acting parasympathomimetic drug in
dementia disorders and in acute cerebrovascular disease.
Thirteen published clinical trials, examining in total 4,054
patients, have evaluated the use of choline alphoscerate in
various forms of dementia disorders of degenerative, vascular
or combined origin, such as senile dementia of the
Alzheimers type (SDAT) or vascular dementia (VaD) and in
acute cerebrovascular diseases, such as transitory ischemic
attack (TIA) and stroke. Analysis has assessed the design of
each study, in particular with respect to experimental design,
number of cases, duration of treatment and tests used to
evaluate drug clinical efficacy. Most of the 10 studies
performed in dementia disorders were controlled trials versus
a reference drug or placebo. Overall, 1,570 patients were
assessed in these studies, 854 of which in controlled trials.
As detected by validated and appropriate tests, such as Mini
Mental State Evaluation (MMSE) in SDAT and Sandoz Clinical
Assessment Geriatric (SCAG) in VaD, administration of choline
alphoscerate significantly improved patient clinical
condition. Clinical results obtained with choline alphoscerate
were superior or equivalent to those observed in control
groups under active treatment and superior to the results
observed in placebo groups. Analysis stresses the clear
internal consistency of clinical data gathered by different
experimental situations on the drug effect, especially with
regard to the cognitive symptoms (memory, attention)
characterizing the clinical picture of adult-onset dementia
disorders. The therapeutic usefulness of choline alphoscerate
in relieving cognitive symptoms of chronic cerebral
deterioration differentiates this drug from cholinergic
precursors used in the past, such as choline and lecithin.
Three uncontrolled trials were performed with choline
alphoscerate in acute cerebrovascular stroke and TIA, totaling
2,484 patients. The results of these trials suggest that this
drug might favor functional recovery of patients with cerebral
stroke and should be confirmed in future investigations aimed
at establishing the efficacy of the drug in achieving
functional recovery of patients with acute cerebrovascular
disease.
Mech Ageing Dev 2001
Nov;122(16):2041-55
Behavioral effects of
L-alpha-glycerylphosphorylcholine: influence on cognitive
mechanisms in the rat.
The phosphorylcholine precursor,
L-alpha-glycerylphosphorylcholine (alpha-GPC), was injected at
the dose of 100 mg/kg/day for 20 days to aged male rats of the
Sprague-Dawley strain, 24 months old, showing a deficit of
learning and memory capacity. The drug was also administered
to rats with amnesia induced pharmacologically with bilateral
injections of kainic acid into the nucleus basalis
magnocellularis (NBM). Learning and memory capacity of the
animals, studied with tests of active and passive avoidance
behavior, was improved after treatment with alpha-GPC in all
experimental groups. These results indicate that this drug
affects cognitive mechanisms in the rat through an involvement
of central neurotransmission.
Pharmacol Biochem Behav 1992
Feb;41(2):445-8
Continued on Page 2 of
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Page 2 of 4
Brain
functionPhosphatidylserine
A review of nutrients and botanicals
in the integrative management of cognitive dysfunction.
Dementias and other severe cognitive dysfunction states
pose a daunting challenge to existing medical management
strategies. An integrative, early intervention approach seems
warranted. Whereas, allopathic treatment options are highly
limited, nutritional and botanical therapies are available
which have proven degrees of efficacy and generally favorable
benefit-to-risk profiles. This review covers five such
therapies: phosphatidylserine (PS), acetyl-l-carnitine (ALC),
vinpocetine, ginkgo biloba extract (GbE) and bacopa monniera
(Bacopa). PS is a phospholipid enriched in the brain,
validated through double-blind trials for improving memory,
learning, concentration, word recall and mood in middle-aged
and elderly subjects with dementia or age-related cognitive
decline. PS has an excellent benefit-to-risk profile. ALC is
an energizer and metabolic cofactor which also benefits
various cognitive functions in the middle-aged and elderly,
but with a slightly less favorable benefit-to-risk profile.
Vinpocetine, found in the lesser periwinkle Vinca minor, is an
excellent vasodilator and cerebral metabolic enhancer with
proven benefits for vascular-based cognitive dysfunction. Two
meta-analyses of GbE demonstrate the best preparations and
offer limited benefits for vascular insufficiencies and even
more limited benefits for Alzheimers, while
commodity GbE products offer little benefit, if
any at all. GbE (and probably also vinpocetine) is
incompatible with blood-thinning drugs. Bacopa is an Ayurvedic
botanical with apparent anti-anxiety, anti-fatigue and
memory-strengthening effects. These five substances offer
interesting contributions to a personalized approach for
restoring cognitive function, perhaps eventually in
conjunction with the judicious application of growth
factors.
Altern Med Rev 1999
Jun;4(3):144-61
Double-blind randomized controlled
study of phosphatidylserine in senile demented patients.
A double-blind randomized controlled study was conducted in
42 hospitalized demented patients to evaluate the
therapeutical effect of phosphatidylserine (BC-PS). Half of
the patients received 3 X 100 mg of this product, and the
other half a placebo of the same appearance. After a wash-out
period, prescription lasted for six weeks. To evaluate the
patients, two distinct rating scales were used: the Crichton
Scale and an original one (Peri Scale) designed in our
geriatric unit (see Appendix). A circle crossing test was
added. Out of the 35 patients who completed the trial, 18 had
received placebo and 17 BC-PS. The results indicated a trend
toward improvement in the BC-PS treated patients and an
analysis of covariance showed a significant (p less than 0.05)
treatment effect on the Peri Scale. The results at the end of
the treatment period were compared with those obtained three
weeks later. Here again there was a statistically significant
difference in the Peri Scale results, indicating that
modifications are drug-related. The behavioral improvement
shown in this study is in agreement with experimental studies
on aged animals.
Acta Neurol Scand 1986
Feb;73(2):136-40
Effects of phosphatidylserine in
age-associated memory impairment.
We treated 149 patients meeting criteria for age-associated
memory impairment (AAMI) for 12 weeks with a formulation of
phosphatidylserine (100 mg BC-PS tid) or placebo. Patients
treated with the drug improved relative to those treated with
placebo on performance tests related to learning and memory
tasks of daily life. Analysis of clinical subgroups suggested
that persons within the sample who performed at a relatively
low level prior to treatment were most likely to respond to
BC-PS. Within this subgroup, there was improvement on both
computerized and standard neuropsychological performance
tests, and also on clinical global ratings of improvement. The
results suggest that the compound may be a promising candidate
for treating memory loss in later life.
Neurology 1991 May;41(5):644-9
Cognitive decline in the elderly: a
double-blind, placebo-controlled multicenter study on efficacy
of phosphatidylserine administration.
This double-blind study assesses the therapeutic efficacy
and the safety of oral treatment with phosphatidylserine
(BC-PS) vs placebo (300 mg/day for six months) in a group of
geriatric patients with cognitive impairment. A total of 494
elderly patients (age between 65 and 93 years), with moderate
to severe cognitive decline, according to the Mini Mental
State Examination and Global Deterioration Scale, were
recruited in 23 Geriatric or General Medicine Units in
Northeastern Italy. Sixty-nine patients dropped out within the
six-month trial period. Patients were examined just before
starting therapy, and three and six months thereafter. The
efficacy of treatment compared to placebo was measured on the
basis of changes occurring in behavior and cognitive
performance using the Plutchik Geriatric Rating Scale and the
Buschke Selective Reminding Test. Statistically significant
improvements in the phosphatidylserine-treated group compared
to placebo were observed both in terms of behavioral and
cognitive parameters. In addition, clinical evaluation and
laboratory tests demonstrated that BC-PS was well tolerated.
These results are clinically important since the patients were
representative of the geriatric population commonly met in
clinical practice.
Aging (Milano) 1993
Apr;5(2):123-33
Double-blind study with
phosphatidylserine (PS) in parkinsonian patients with senile
dementia of Alzheimers type (SDAT).
Experimental and clinical studies showed that
phosphatidylserinespecial preparation from cows
brain by FIDIA, Abano Terme, Italyis able to influence
cerebral changes contributed to the symptoms of senile
dementia of Alzheimers type. The application of the
computerized EEG (CEEG) method Dynamic Brain Mapping (HZI
Research Center, Tarrytown, New York) is able to proof the
therapeutic effect of phosphatidylserine: the acceleration of
a slowed EEG in Parkinsonian patients with SDAT. These
reactions were seen previous to the favorable clinical
influence documented by the Sandoz Clinical Assessment
Geriatric Scale (SCAG), which showed a significant
amelioration in anxiety, motivation and affectivity by the
verum drug. Acute and long-term CEEG resultstill 18
monthsshowed that the so-called theta anteriorization
can be reduced or even abolished; this is replaced by alpha
waves. Even in preclinical cerebral changes this method open
the possibility to show incipient alterations of the brain
metabolism. Preliminary therapeutic results leads to this and
not proven hypothesis that prevention or retardation of
cerebral aging might be possible.
Prog Clin Biol Res
1989;317:1235-46
Phosphatidylserine in the treatment of
clinically diagnosed Alzheimers disease. The SMID
Group.
Modifications in cellular membranes can be observed in
aging and Alzheimers disease (AD). These mainly concern
the degree of the membranes viscosity, with consequent
reduction of the activity of some protein structures, such as
enzymes, receptors and membrane carriers. Moreover, dendritic
spine loss, found in aging and AD brain, is one of the most
characteristic findings. BC-PS, a phospholipid, purified from
bovine brain, is found to be able to influence positively the
above cited modifications. Moreover, BC-PS administration to
old rats improves the performances in some memory tests. In
humans, the effects of BC-PS have been studied by some
controlled trials in AD and related cognitive disorders. The
most recent of these trials, conducted on an Italian
population of AD patients is presented here, emphasizing in
particular its methodological aspects.
J Neural Transm Suppl
1987;24:287-92
Effects of phosphatidylserine in
Alzheimers disease.
We studied 51 patients meeting clinical criteria for
probable Alzheimers disease (AD). Patients were treated
for 12 weeks with a formulation of bovine cortex
phosphatidylserine (BC-PS; 100 mg tid) or placebo, and those
treated with the drug improved on several cognitive measures
relative to those administered placebo. Differences between
treatment groups were most apparent among patients with less
severe cognitive impairment. Results suggest that
phosphatidylserine may be a promising candidate for study in
the early stages of AD.
Psychopharmacol Bull
1992;28(1):61-6
Double-blind cross-over study of
phosphatidylserine vs. placebo in patients with early dementia
of the Alzheimer type.
Thirty-three patients with mild primary degenerative
dementia according to DSM-III (MMS between 15 and 27) took
part in a double-blind cross-over study of phosphatidylserine
(Fidia 300 mg/d) versus placebo. Both treatment phases lasted
for eight weeks with an eight week washout phase in between
and a four week washout phase before treatment phase one.
Clinical global improvement ratings showed significantly more
patients improving under phosphatidylserine (BC-PS) than under
placebo during treatment phase one. The improvement carried
over to the following wash-out and treatment phases. There
were no significant improvements in GBS dementia rating scale,
psychometric tests or P300-latency. 16-channel EEG mapping
findings indicated that the patients initially showed higher
power values in all frequency bands (except alpha), when
compared to a younger, healthy control group. BC-PS reduced
the higher power values compared to placebo, shifting EEG
power more towards the normal level.
Eur Neuropsychopharmacol 1992
Jun;2(2):149-55
Effects of phosphatidylserine therapy
in geriatric patients with depressive disorders.
The effects of phosphatidylserine (BC-PS) on cognitive,
affective and behavioural symptoms were studied in a group of
10 elderly women with depressive disorders. Patients were
treated with placebo for 15 days, followed by BC-PS (300
mg/day) for 30 days. The Hamilton Rating Scale for Depression,
Gottfries-Brane-Steen Rating Scale, Nurses Observation
Scale for Inpatient Evaluation and Buschke Selective Reminding
Test were administered before and after placebo and after
BC-PS therapy to monitor changes in depression, memory and
general behavior. At the same time, basal plasma levels of
noradrenaline, MHPG, DOPAC, HVA and 5-HIAA, and
GH/beta-endorphin/beta-lipotropin responses to clonidine
stimulation were measured. BC-PS induced consistent
improvement of depressive symptoms, memory and behavior. No
changes in amine metabolite levels or in hormonal responses to
alpha 2-adrenoceptor stimulation were observed.
Acta Psychiatr Scand 1990
Mar;81(3):265-70
Blunting by chronic phosphatidylserine
administration of the stress-induced activation of the
hypothalamo-pituitary-adrenal axis in healthy men.
The effect of chronic administration of phosphatidylserine
derived from brain cortex on the neuroendocrine responses to
physical stress has been examined in a placebo-controlled
study in nine healthy men. Phosphatidylserine 800 mg/d for 10
days significantly blunted the ACTH and cortisol responses to
physical exercise (P = 0.003 and P = 0.03, respectively),
without affecting the rise in plasma GH and PRL. Physical
exercise significantly increased the plasma lactate
concentration both after placebo and phosphatidylserine. The
results suggest that chronic oral administration of
phosphatidylserine may counteract stress-induced activation of
the hypothalamo-pituitary-adrenal axis in man.
Eur J Clin Pharmacol
1992;42(4):385-8
Effects of phosphatidylserine on the
neuroendocrine response to physical stress in humans.
The activity of brain cortex-derived phosphatidylserine
(BC-PS) on the neuroendocrine and neurovegetative responses to
physical stress was tested in eight healthy men who underwent
three experiments with a bicycle ergometer. According to a
double-blind design, before starting the exercise, each
subject received intravenously, within 10 min, 50 mg or 75 mg
of BC-PS or a volume-matched placebo diluted in 100 ml of
saline. Blood samples were collected before and after the
exercise for plasma epinephrine (E), norepinephrine (NE),
dopamine (DA), adrenocorticotropin (ACTH), cortisol, growth
hormone (GH), prolactin (PRL) and glucose determinations.
Blood pressure and heart rate were also recorded. Physical
stress induced a clear-cut increase in plasma E, NE, ACTH,
cortisol, GH and PRL, whereas no significant change was
observed in plasma DA and glucose. Pretreatment with both 50
mg and 75 mg BC-PS significantly blunted the ACTH and cortisol
responses to physical stress.
Neuroendocrinology 1990
Sep;52(3):243-8
The influence of phosphatidylserine
supplementation on mood and heart rate when faced with an
acute stressor.
There have been previous reports that supplements of
phosphatidylserine (PS) blunted the release of cortisol in
response to exercise stress and that it improved mood. The
present study extended these observations by considering
whether PS supplementation influenced subjective feelings of
stress and the change in heart rate when a stressful mental
arithmetic task was performed. In young adults with
neuroticism scores above rather than below the median, the
taking of 300 mg PS each day for a month was associated with
feeling less stressed and having a better mood. The study for
the first time reports an improvement in mood following PS
supplementation in a sub-group of young healthy adults.
Nutr Neurosci 2001;4(3):169-78
Continued on Page 3 of
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Page 3 of 4
OsteoporosisBisphosphonates
Bisphosphonates: safety and efficacy
in the treatment and prevention of osteoporosis.
Osteoporosis affects more than 28 million Americans. With
the advent of accessible and affordable diagnostic studies,
awareness and recognition of this disease by patients and
clinicians are growing. Osteoporotic fractures of the spine
and hip are costly and associated with significant morbidity
and mortality. Over the past decade, a surge of new
antiosteoporotic drugs have been labeled or are awaiting
labeling by the U.S. Food and Drug Administration. One class
of agents used to treat osteoporosis is the bisphosphonates,
which inhibit bone resorption, cause an increase in bone
mineral density and reduce the risk of future fractures caused
by aging, estrogen deficiency and corticosteroid use. Overall,
bisphosphonates have been shown to have a strong safety and
tolerability profile.
Am Fam Physician 2000 May
1;61(9):2731-6
Bisphosphonates: preclinical aspects
and use in osteoporosis.
Bisphosphonates are synthetic compounds characterized by a
P-C-P bond. They have a strong affinity to calcium phosphates
and hence to bone mineral. In vitro they inhibit both
formation and dissolution of the latter. Many of the
bisphosphonates inhibit bone resorption, the newest compounds
being 10,000 times more active than etidronate, the first
bisphosphonate described. The antiresorbing effect is cell
mediated, partly by a direct action on the osteoclasts, partly
through the osteoblasts, which produce an inhibitor of
osteoclastic recruitment. When given in large amounts, some
bisphosphonates can also inhibit normal and ectopic
mineralization through a physical-chemical inhibition of
crystal growth. In the growing rat the inhibition of
resorption is accompanied by an increase in intestinal
absorption and an increased balance of calcium.
Bisphosphonates also prevent various types of experimental
osteoporosis, such as after immobilization, ovariectomy,
orchidectomy, administration of corticosteroids or low calcium
diet. The P-C-P bond of the bisphosphonates is completely
resistant to enzymatic hydrolysis. The bisphosphonates studied
up to now, such as etidronate, clodronate, pamidronate, and
alendronate, are absorbed, stored and excreted unaltered. The
intestinal absorption of the bisphosphonates is low, between
1% or less and 10% of the amount ingested. The newer
bisphosphonates are at the lower end of the scale. The
absorption diminishes when the compounds are given with food,
especially in the presence of calcium. Bisphosphonates are
rapidly cleared from plasma, 20% to 80% being deposited in
bone and the remainder excreted in the urine. In bone, they
deposit at sites of mineralization as well as under the
osteoclasts. In contrast to plasma, the half-life in bone is
very long, partially as long as the half-life of the bone in
which they are deposited. In humans, bisphosphonates are used
successfully in diseases with increased bone turnover, such as
Pagets disease, tumoural bone disease, as well as in
osteoporosis. Various bisphosphonates, such as alendronate,
clodronate, etidronate, ibandronate, pamidronate and
tiludronate, have been investigated in osteoporosis. All
inhibit bone loss in postmenopausal women and increase bone
mass. Furthermore, bisphosphonates are also effective in
preventing bone loss both in corticosteroid-treated and in
immobilized patients. The effect on the rate of fractures has
recently been proven for alendronate. In humans, the adverse
effects depend upon the compound and the amount given. For
etidronate, practically the only adverse effect is an
inhibition of mineralization. The aminoderivatives induce for
a period of two to three days a syndrome with pyrexia, which
shows a similitude with an acute phase reaction. The more
potent compounds can induce gastrointestinal disturbances,
sometimes oesophagitis, when given orally. Bisphosphonates are
an important addition to the therapeutic possibilities in the
prevention and treatment of osteoporosis.
Ann Med 1997 Feb;29(1):55-62
Osteoporosis - evidence based
therapy.
Osteoporosis therapy has been controversially discussed in
the past. In the meantime, several therapeutic options to
prevent fractures are available for this disease. With respect
to proven fracture benefit, however, the quality of evidence
from randomized and controlled clinical trials varies
substantially among therapies. From systematic research the
best external evidence is available for a supplementation with
calcium and vitamin D and a therapy with the bisphosphonates
alendronate or risedronate, as well as the SERM raloxifene.
For other therapeutic agents like fluorides, vitamin D
metabolites, calcitonin and etidronate the quality of evidence
is much lower. So far, there is no evidence for other
pharmaceutical therapies. Hip protectors are effective in the
prevention of hip fractures.
Z Gastroenterol 2002 Apr;40 Suppl
1:57-61
Bisphosphonate therapy in
osteoporosis. Inhibition of trabecular perforation by
aminobisphosphonate.
After many years of experience with bisophosphonates in the
treatment of tumor osteopathy and Pagets
disease, these substances have now also been approved for use
in the treatment of osteoporosis. Owing to their high affinity
for calcium hydroxyapatite, the bisphosphonates are deposited
in the bony surface, and the aminobisphosphonates exert their
effect at the site of active resorption via direct inhibition
of active osteoclasts. As a result of this inhibition of the
osteoclastic bone resorption, trabecular perforation is
reduced and during the course of bone remodelling by the
activity of the osteoblasts, boneformation occurs. In addition
to an increase in bone density, both etidronate and
alendronate have been shown to inhibit vertebral fractures in
patients with osteoporosis. In addition, in patients with
preexisting fractures, alendronate is able, at the same time,
to lower the incidence of fractures of the femoral neck. With
proper administration, the associated occasional
gastrointestinal side effects can be avoided. The introduction
of bisphosphonates into the treatment of osteoporosis is
definitely an enrichment of the therapeutic spectrum in
conjunction with the basic treatment comprising calcium,
vitamin D, diet and physical measures.
Fortschr Med 1997 Oct
20;115(29):37-42
Bisphosphonates: from the laboratory
to the clinic and back again.
Bisphosphonates (BPs) used as inhibitors of bone resorption
all contain two phosphonate groups attached to a single carbon
atom, forming a P-C-P structure. The
bisphosphonates are therefore stable analogues of naturally
occurring pyrophosphate-containing compounds, which now helps
to explain their intracellular as well as their extracellular
modes of action. Bisphosphonates adsorb to bone mineral and
inhibit bone resorption. The mode of action of bisphosphonates
was originally ascribed to physico-chemical effects on
hydroxyapatite crystals, but it has gradually become clear
that cellular effects must also be involved. The marked
structure-activity relationships observed among more complex
compounds indicate that the pharmacophore required for maximal
activity not only depends upon the bisphosphonate moiety but
also on key features, e.g., nitrogen substitution in alkyl or
heterocyclic side chains. Several bisphosphonates (e.g.,
etidronate, clodronate, pamidronate, alendronate, tiludronate,
risedronate, and ibandronate) are established as effective
treatments in clinical disorders such as Pagets disease
of bone, myeloma and bone metastases. Bisphosphonates are also
now well established as successful antiresorptive agents for
the prevention and treatment of osteoporosis. In particular,
etidronate and alendronate are approved as therapies in many
countries, and both can increase bone mass and produce a
reduction in fracture rates to approximately half of control
rates at the spine, hip, and other sites in postmenopausal
women. In addition to inhibition of osteoclasts, the ability
of bisphosphonates to reduce the activation frequency and
birth rates of new bone remodeling units, and possibly to
enhance osteon mineralization, may also contribute to the
reduction in fractures. The clinical pharmacology of
bisphosphonates is characterized by low intestinal absorption,
but highly selective localization and retention in bone.
Significant side effects are minimal. Current issues with
bisphosphonates include the introduction of new compounds, the
choice of therapeutic regimen (e.g., the use of intermittent
dosing rather than continuous), intravenous vs. oral therapy,
the optimal duration of therapy, the combination with other
drugs, and extension of their use to other conditions,
including steroid-associated osteoporosis, male osteoporosis,
arthritis, and osteopenic disorders in childhood.
Bisphosphonates inhibit bone resorption by being selectively
taken up and adsorbed to mineral surfaces in bone, where they
interfere with the action of osteoclasts. It is likely that
bisphosphonates are internalized by osteoclasts and interfere
with specific biochemical processes and induce apoptosis. The
molecular mechanisms by which these effects are brought about
are becoming clearer. Recent studies show that bisphosphonates
can be classified into at least two groups with different
modes of action. Bisphosphonates that closely resemble
pyrophosphate (such as clodronate and etidronate) can be
metabolically incorporated into nonhydrolysable analogues of
ATP that may inhibit ATP-dependent intracellular enzymes. The
more potent, nitrogen-containing bisphosphonates (such as
pamidronate, alendronate, risedronate, and ibandronate) are
not metabolized in this way but can inhibit enzymes of the
mevalonate pathway, thereby preventing the biosynthesis of
isoprenoid compounds that are essential for the
post-translational modification of small GTPases. The
inhibition of protein prenylation and the disruption of the
function of these key regulatory proteins explains the loss of
osteoclast activity and induction of apoptosis. These
different modes of action might account for subtle differences
between compounds in terms of their clinical effects. In
conclusion, bisphosphonates are now established as an
important class of drugs for the treatment of bone diseases,
and their mode of action is being unraveled. As a result,
their full therapeutic potential is gradual.
Bone 1999 Jul;25(1):97-106
Continuous therapy with pamidronate, a
potent bisphosphonate, in postmenopausal osteoporosis.
There is a need for effective and acceptable therapies for
postmenopausal osteoporosis. The bisphosphonates show promise
in this role, but the effects of the potent bisphosphonates in
established osteoporosis have not yet been reported. We
performed a 2-yr, randomized, double blind, placebo-controlled
trial of pamidronate (150 mg/day) in 48 postmenopausal
osteoporotic women. Bone mineral density of the total body,
lumbar spine and proximal femur was measured every six months
by dual energy x-ray absorptiometry. Bone mineral density
increased progressively in the total body (1.9 +/- 0.7%; P
< 0.01), lumbar spine (7.0 +/- 1.0%; P < 0.0001), and
femoral trochanter (5.4 +/- 1.3%; P < 0.001) in subjects
receiving pamidronate, but did not change significantly in
those receiving placebo. There were significant decreases in
bone density at both the femoral neck (P < 0.02) and
Wards triangle (P < 0.01) in subjects taking placebo,
which did not occur in the pamidronate group. The differences
between the treatment groups were significant at all sites
(0.0001 < P < 0.05) except Wards triangle.
Vertebral fracture rates were 13/100 patient yr in the
pamidronate group and 24/100 patient yr in those receiving
placebo (P = 0.07), and there was a nonsignificant trend
toward height loss being less in those receiving pamidronate
(P = 0.16). It is concluded that pamidronate is an effective
therapy in postmenopausal osteoporosis.
J Clin Endocrinol Metab 1994
Dec;79(6):1595-9
Continued on Page 4 of
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LE Magazine September 2002

Page 4 of 4
Sports endurance
Health implications of creatine: can
oral creatine supplementation protect against neurological and
atherosclerotic disease?
Major achievements made over the last several years have
highlighted the important roles of creatine and the creatine
kinase reaction in health and disease. Inborn errors of
metabolism have been identified in the three main steps
involved in creatine metabolism: arginine: glycine
amidinotransferase (AGAT), S-adenosyl-L-methionine:
N-guanidinoacetate methyltransferase (GAMT) and the creatine
transporter. All these diseases are characterized by a lack of
creatine and phosphorylcreatine in the brain, and by (severe)
mental retardation. Similarly, knockout mice lacking the brain
cytosolic and mitochondrial isoenzymes of creatine kinase
displayed a slightly increased creatine concentration, but no
phosphorylcreatine in the brain. These mice revealed decreased
weight gain and reduced life expectancy, disturbed fat
metabolism, behavioral abnormalities and impaired learning
capacity. Oral creatine supplementation improved the clinical
symptoms in both AGAT and GAMT deficiency, but not in creatine
transporter deficiency. In addition, creatine supplementation
displayed neuroprotective effects in several animal models of
neurological disease, such as Huntingtons disease,
Parkinsons disease or amyotrophic lateral sclerosis. All
these findings pinpoint to a close correlation between the
functional capacity of the creatine
kinase/phosphorylcreatine/creatine system and proper brain
function. They also offer a starting-point for novel means of
delaying neurodegenerative disease, and/or for strengthening
memory function and intellectual capabilities. Finally,
creatine biosynthesis has been postulated as a major effector
of homocysteine concentration in the plasma, which has been
identified as an independent graded risk factor for
atherosclerotic disease. By decreasing homocysteine
production, oral creatine supplementation may, thus, also
lower the risk for developing, e.g., coronary heart disease or
cerebrovascular disease. Although compelling, these results
require further confirmation in clinical studies in humans,
together with a thorough evaluation of the safety of oral
creatine supplementation.
Neuroscience 2002;112(2):243-60
Effects of creatine supplementation on
exercise performance and muscular strength in amyotrophic
lateral sclerosis: preliminary results.
Creatine supplementation in humans has been reported to
enhance power and strength both in normal subjects and in
patients with various neuromuscular diseases. The purpose of
this study was to examine the effects of supplementation on
exercise performance and maximal voluntary isometric muscular
contraction (MVIC) in amyotrophic lateral sclerosis (ALS)
patients. We report the results obtained in 28 patients with
probable/definite ALS. In each patient we acquired the
dynamometric measurement of MVIC in 10 muscle groups of upper
and lower limbs and a measure of fatigue by means of a
high-intensity intermittent protocol in elbow flexors and knee
extensors muscles. All patients completed the protocols at the
baseline and after supplementation of 20 g per day for seven
days and after supplementation of 3 g per day for three and
six months. MVIC increased after seven days of supplementation
in 20 patients (70%) in knee extensors and in 15 (53%) of them
also in elbow flexors. A statistically significant difference
between pre and post-treatment mean values of MVIC was found
both in elbow flexors (P<0.05) and knee extensors
(p<0.04). The analysis of the slopes of fatigue test showed
a statistically significant improvement after seven days of
supplementation in 11 patients (39%) in elbow flexors and in
nine patients (32%) also in knee extensors muscles. During the
six month follow-up period all the examined parameters showed
a linear progressive decline. In conclusion, our preliminary
results have demonstrated that supplementation temporarily
increases maximal isometric power in ALS patients so it may be
of potential benefit in situations such as high intensity
activity and it can be proposed as a symptomatic
treatment.
J Neurol Sci 2001 Oct
15;191(1-2):139-44
DHEA treatment reduces fat
accumulation and protects against insulin resistance in male
rats.
The purpose of this study was to determine whether
administration of dehydroepiandrosterone (DHEA) protects male
rats against the accumulation of body fat and the development
of insulin resistance with advancing age. We found that
supplementation of the diet with 0.3% DHEA between the ages of
five months and approximately 25 months resulted in a
significantly lower final body weight (DHEA, 593 +/- 18 g vs
control, 668 +/- 12 g, p < 0.02), despite no decrease in
food intake. Lean body mass was unaffected by the DHEA, and
the lower body weight was due to a approximately 25% reduction
in body fat. The rate of glucose disposal during a euglycemic,
hyperinsulinemic clamp was 30% higher in the DHEA group than
in the sedentary controls due to a greater insulin
responsiveness. The DHEA administration was as effective in
reducing body fat content and maintaining insulin
responsiveness as exercise in the form of voluntary wheel
running. The DHEA had no significant effect on muscle GLUT4
content. A preliminary experiment provided evidence suggesting
that muscle insulin signaling, as reflected in binding of
phosphatidylinositol 3-kinase to the insulin receptor
substrate-1, was enhanced in the DHEA-treated and wheel
running groups as compared to controls. These results provide
evidence that DHEA, like exercise, protects against excess fat
accumulation and development of insulin resistance in
rats.
J Gerontol A Biol Sci Med Sci 1998
Jan;53(1):B19-24
Herbal ephedra/caffeine for weight
loss: a six month randomized safety and efficacy trial.
OBJECTIVE: To examine long-term safety and efficacy for
weight loss of an herbal Ma Huang and Kola nut supplement
(90/192 mg/day ephedrine alkaloids/caffeine). DESIGN: Six
month randomized, double-blind placebo controlled trial.
SUBJECTS: A total of 167 subjects (body mass index (BMI)
31.8+/-4.1 kg/m(2)) randomized to placebo (n=84) or herbal
treatment (n=83) at two outpatient weight control research
units. MEASUREMENTS: Primary outcome measurements were changes
in blood pressure, heart function and body weight. Secondary
variables included body composition and metabolic changes.
RESULTS: By last observation carried forward analysis, herbal
vs placebo treatment decreased body weight (-5.3+/-5.0 vs
-2.6+/-3.2 kg, P<0.001), body fat (-4.3+/-3.3 vs -2.7+/-2.8
kg, P=0.020) and LDL-cholesterol (-8+/-20 vs 0+/-17 mg/dl,
P=0.013), and increased HDL-cholesterol (+2.7+/-5.7 vs
-0.3+/-6.7 mg/dl, P=0.004). Herbal treatment produced small
changes in blood pressure variables (+3 to -5 mmHg,
P</=0.05), and increased heart rate (4+/-9 vs -3+/-9 bpm,
P<0.001), but cardiac arrhythmias were not increased
(P>0.05). By self-report, dry mouth (P<0.01), heartburn
(P<0.05), and insomnia (P<0.01) were increased and
diarrhea decreased (P<0.05). Irritability, nausea, chest
pain and palpitations did not differ, nor did numbers of
subjects who withdrew. CONCLUSIONS: In this six month
placebo-controlled trial, herbal ephedra/caffeine (90/192
mg/day) promoted body weight and body fat reduction and
improved blood lipids without significant adverse events.
Int J Obes Relat Metab Disord 2002
May;26(5):593-604
Nutrition and dietary supplements.
Quality and number of subjects in blinded controlled
clinical trials about the nutrition and dietary supplements
discussed here is variable. Glucosamine sulfate and
chondroitin sulfate have sufficient controlled trials to
warrant their use in osteoarthritis, having less side effects
than currently used nonsteroidal anti-inflammatory drugs, and
are the only treatment shown to prevent progression of the
disease. Dietary supplements of ephedrine plus caffeine for
weight loss (weight loss being the current first line
recommendation of physicians for osteoporosis) show some
promise, but are not sufficient in number of study subjects.
Phenylpropanolamine is proven successful in weight loss. Both
ephedrine and phenylpropanolamine have resulted in deaths and
hence are worrisome as an over-the-counter dietary supplement.
Other commonly used weight loss supplements like Cola
acuminata, dwarf elder, yohimbine and garcinia camborgia are
either lacking controlled clinical trials, or in the case of
the last two supplements, have clinical trials showing lack of
effectiveness (although garcinia has been successful in trials
as part of a mixture with other substances, it is unclear if
it was a necessary part of the mixture). Safety of these
weight loss supplements is unknown. Chromium as a body
building supplement for athletes appears to have no efficacy.
Creatine may help more in weight lifting than sprinting, but
insufficient study subjects and safety information make more
studies necessary. Carbohydrate loading is used commonly
before endurance competitions, but may be underused as it may
be beneficial for other sport performances. Supplements for
muscle injury or cramps have had too few studies to determine
efficacy. Although proper rehydration with fluids and
electrolytes is necessary, a paucity of actual studies to
maximize prophylactic treatment for exercise induced cramping
still exists. Nutritional supplements for cardiovascular
disorders are generally geared to prevention. The United
States Department of Agriculture has good recommendations to
prevent atherosclerosis; a stricter version by Ornish was
shown to reverse coronary heart disease, and the low meat,
high fruit, and vegetable DASH diet has been found to decrease
hypertension. The epidemiologic studies of
hyperhomocysteinemia are impressive enough to give folic acid
(or vitamin B6 or B12) supplements to those with elevated
homocysteine levels and test patients who have a history of
atherosclerotic disease, but no controlled clinical trials
have been completed. Soluble fiber has several positive
studies in reduction of cholesterol levels and generally is
accepted. The data on vitamin E are the most confusing. This
vitamin was not helpful in cerebrovascular prevention in China
and not helpful at relatively small doses (50 mg) in the
United States or Finland against major coronary events. Levels
of 400 mg appeared to decrease cardiovascular disease in the
United States in studies based on reports by patients and in
one large clinical trial. Vitamin E also was successful in
prevention of restenosis after PTCA in one clinical trial.
Both of these clinical trials need to be repeated in other
developed country populations. Some nutritional and dietary
supplements are justifiably useful at this point in time.
Several meet the criteria of a late Phase 3 FDA clinical trial
(where it would be released for public use), but many dietary
supplements have insufficient numbers of studies. Some deaths
also have occurred with some supplements. If these supplements
were required to undergo clinical trials necessary for a new
drug by the FDA, they would not be released yet to the public.
Several nontoxic supplements appear promising, though need
further study. Because they have essentially no toxicity (such
as folic acid with B12, soluble fiber and vitamin E) and may
have efficacy, some of these supplementations may be useful
now, without randomized clinical trials.
Phys Med Rehabil Clin N Am 1999
Aug;10(3):673-703
Ephedrine, caffeine and aspirin:
safety and efficacy for treatment of human obesity.
The safety and efficacy of a mixture of ephedrine (75 to
150mg), caffeine (150mg) and aspirin (330mg), in divided
premeal doses, were investigated in 24 obese humans (mean BMI
37.0) in a randomized double blind placebo-controlled trial.
Energy intake was not restricted. Overall weight loss over
eight weeks was 2.2kg for ECA vs. 0.7 kg for placebo (p <
0.05). Eight of 13 placebo subjects returned five months later
and received ECA in an unblinded crossover. After eight weeks,
mean weight loss with ECA (ephedrine, caffeine and aspirin)
was 3.2 kg vs 1.3 kg for placebo (p = 0.036). Six subjects
continued on ECA for seven to 26 months. After five months on
ECA, average weight loss in five of these was 5.2 kg compared
to 0.03 kg gained during five months between studies with no
intervention (p = 0.03). The sixth subject lost 66 kg over 13
months by self-imposed caloric restriction. In all studies, no
significant changes in heart rate, blood pressure, blood
glucose, insulin, and cholesterol levels, and no differences
in the frequency of side effects were found. ECA in these
doses is thus well tolerated in otherwise healthy obese
subjects, and supports modest, sustained weight loss even
without prescribed caloric restriction, and may be more
effective in conjunction with restriction of energy
intake.
Int J Obes Relat Metab Disord 1993
Feb;17 Suppl 1:S73-8
Detection and determination of
anabolic steroids in nutritional supplements.
A method is described for the determination of anabolic
steroids including testosterone,
19-nor-4-androstene-3,17-dione, 4-androstene-3,17-dione and
nandrolone in food supplements. Initial clean-up is done by
HPLC followed by determination with GC/MS. A
contaminated food supplement was analyzed and
appeared to contain 19-nor-4-androstene-3,17-dione and
4-androstene-3,17-dione. One capsule of this nutritional
supplement was ingested by five male volunteers. Urine samples
were collected and analyzed by GC/MS and GC/MS-MS. Neither the
ratio testosterone/epitestosterone, nor the ratio
androstenedione/epitestosterone increased significantly.
Concentrations above 2 ng/ml for norandrosterone, the major
metabolite of nandrolone, were detected until 48-144 h after
ingestion of the food supplement.
J Pharm Biomed Anal 2001
Jul;25(5-6):843-52
Effect of oral androstenedione on
serum testosterone and adaptations to resistance training in
young men: a randomized controlled trial.
CONTEXT: Androstenedione, a precursor to testosterone, is
marketed to increase blood testosterone concentrations as a
natural alternative to anabolic steroid use. However, whether
androstenedione actually increases blood testosterone levels
or produces anabolic androgenic effects is not known.
OBJECTIVES: To determine if short- and long-term oral
androstenedione supplementation in men increases serum
testosterone levels and skeletal muscle fiber size and
strength and to examine its effect on blood lipids and markers
of liver function. DESIGN AND SETTING: Eight-week randomized
controlled trial conducted between February and June 1998.
PARTICIPANTS: Thirty healthy, normotestosterogenic men (aged
19 to 29 years) not taking any nutritional supplements or
androgenic-anabolic steroids or engaged in resistance
training. INTERVENTIONS: Twenty subjects performed eight weeks
of whole-body resistance training. During weeks 1, 2, 4, 5, 7
and 8, the men were randomized to either androstenedione, 300
mg/d (n = 10), or placebo (n = 10). The effect of a single
100-mg androstenedione dose on serum testosterone and estrogen
concentrations was determined in 10 men. MAIN OUTCOME
MEASURES: Changes in serum testosterone and estrogen
concentrations, muscle strength, muscle fiber cross-sectional
area, body composition, blood lipids, and liver transaminase
activities based on assessments before and after short- and
long-term androstenedione administration. RESULTS: Serum free
and total testosterone concentrations were not affected by
short- or long-term androstenedione administration. Serum
estradiol concentration (mean [SEM]) was higher (P<.05) in
the androstenedione group after two (310 [20] pmol/L), five
(300 [30] pmol/L) and eight (280 [20] pmol/L) weeks compared
with presupplementation values (220 [20] pmol/L). The serum
estrone concentration was significantly higher (P<.05)
after two (153 [12] pmol/L) and five (142 [15] pmol/L) weeks
of androstenedione supplementation compared with baseline (106
[11] pmol/L). Knee extension strength increased significantly
(P<.05) and similarly in the placebo (770 [55] N vs 1095
[52] N) and androstenedione (717 [46] N vs 1024 [57] N)
groups. The increase of the mean cross-sectional area of type
2 muscle fibers was also similar in androstenedione (4703
[471] vs 5307 [604] mm2; P<.05) and placebo (5271 [485] vs
5728 [451] mm2; P<.05) groups. The significant (P<.05)
increases in lean body mass and decreases in fat mass were
also not different in the androstenedione and placebo groups.
In the androstenedione group, the serum high-density
lipoprotein cholesterol concentration was reduced after two
weeks (1.09 [0.08] mmol/L [42 (3) mg/dL] vs 0.96 [0.08] mmol/L
[37 (3) mg/dL]; P<.05) and remained low after five and
eight weeks of training and supplementation. CONCLUSIONS:
Androstenedione supplementation does not increase serum
testosterone concentrations or enhance skeletal muscle
adaptations to resistance training in normotestosterogenic
young men and may result in adverse health consequences.
JAMA 1999 Jun 2;281(21):2020-8
Androgen use by athletes: a
reevaluation of the health risks.
It has been estimated that one to three million male and
female athletes in the United States have used androgens.
Androgen use has been associated with liver dysfunction,
altered blood lipids, infertility, musculotendinous injury and
psychological abnormalities. Although androgens have been
available to athletes for more than 50 years, there is little
evidence to show that their use will cause any long-term
detriment. Furthermore, the use of moderate doses of androgens
results in side effects that are largely benign and
reversible. It is our contention that the incidence of serious
health problems associated with the use of androgens by
athletes has been overstated.
Can J Appl Physiol 1996
Dec;21(6):421-40

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