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Statin Update
CoQ10 deficiency in muscle cell mitochondria results in poor cellular respiration.
Oxidative mechanisms and endothelial cell inflammation are recognized as
important factors in coronary heart disease and atherosclerosis. Evidence
shows CoQ10 supplementation can improve the circulatory process and prevent
such irreversible and often fatal conditions as cardiomyopathy, congestive
heart failure, and rhabdolmyolysis (muscle wasting induced by statin drug
toxicity).5
Since their introduction, HMG-CoA reductase drugs (statins) have
helped millions of people to lower their cholesterol levels. At
the same time, however, studies have shown that statin stalwarts
such as Lipitor® (atorvastatin),6,7 Zocor® (simvastatin),7 Pravacol® (pravastatin),7,8 and Mevacor® (lovastatin)8,9 can deplete natural levels of CoQ10 throughout the body.
Statins have surpassed hypertension medications in generating
revenues for pharmaceutical manufacturers, accounting for an estimated
$16 billion in revenues in 2003. These are powerful drugs, but
they also carry the risk of a dose-dependent decrease in the body’s
production of CoQ10. The FDA does not require statin manufacturers
to alert patients and physicians to this potential consequence,
even though many recent studies have demonstrated that CoQ10 deficits
in statin users can cause cognitive, muscular, cardiovascular,
and other problems. Conversely, CoQ10 supplementation can alleviate
these issues in many patients, researchers have found.
Statins sold in Canada are required to carry on their labels
a precautionary warning expressly stating that such CoQ10 depletion
can lead to impaired cardiac functioning in patients with congestive
heart failure. The US government requires no such warning, despite
an emerging generation of “super-statins” (rosuvastatin,
pitavastatin) that may further increase the risk and rate of CoQ10
depletion in patients taking the drugs. Schering-Plough recently
introduced Zetia®, a product that quadruples the dose of first-generation
statins. The FDA approved another powerful drug, Astra-Zeneca’s
Crestor®, in August 2003.
Canadian health authorities require
that statins sold in Canada carry a precautionary warning
regarding CoQ10 depletion. Pfizer’s Lipitor® contains
the
following warning:
The Effect on
Ubiquinone
(CoQ10) Levels
“Significant decreases in circulating ubiquinone
levels in patients treated with atorvastatin and other
statins have been observed. The clinical significance
of a potential long-term statin-induced deficiency of
ubiquinone has not been established. It has been reported
that a decrease in myocardial ubiquinone levels could
lead to impaired cardiac function in patients with borderline
congestive heart failure . . .” |
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Writing in the November 2003 issue of Smart Money magazine, journalist
Eleanor Laise took Pfizer to task for failing to address patients
who have suffered memory loss, severe muscle pain, and other symptoms
of CoQ10 depletion after taking the company’s best-selling
statin Lipitor“. She noted that Pfizer has thus far balked
at acknowledging any association between statins, CoQ10 depletion,
and serious side effects.10
While drug manufacturers and the FDA have yet to weigh in on
the issue, Merck, maker of the popular Zocor“, applied for
patents in 1989 and 1990 for CoQ10-simvastatin combination products.
The company’s 1989 patent application states that a combined
statin-CoQ10 product might be effective against not only cardiomyopathy,
but also elevated levels of the enzyme transaminase, which reflects
liver damage. The company has thus far declined to exercise these
patents, and the FDA and other major drug manufacturers have yet
to acknowledge the risk of CoQ10 depletion from statins.
According to a Pfizer official quoted in the Smart Money article,
the drug company has been unable to document “any specific
effect” on the heart muscle during clinical trials, a surprising
statement considering that several studies by respected medical
researchers at the time Lipitor“ was being tested warned
of the cardiovascular dangers of CoQ10 depletion.
“The depletion of the essential nutrient CoQ10 by the increasingly
popular cholesterol-lowering drugs HMG-CoA reductase inhibitors
(statins) has grown from a level of concern to one of alarm,” notes
Dr. Peter Langsjoen of East Texas University, in a comprehensive
review of animal and human studies of statins and CoQ10 depletion
published last year in the journal Biofactors.6 “With ever
higher statin potencies and doses, and with a steadily shrinking
target LDL cholesterol, the prevalence and severity of CoQ10 deficiency
are increasing noticeably.”
Under revised target cholesterol guidelines issued by the National
Institutes of Health in 2001, as many as 36 million Americans are
now candidates for therapeutic statin intervention, up from 13
million under the old guidelines. Yet the issue of CoQ10 depletion
remains unresolved within the regulatory milieu that addresses
side effects and warning-label requirements.
“We are currently in the midst of a congestive heart failure
epidemic in the United States . . . As physicians it is our duty
to be absolutely certain that we are not inadvertently doing harm
to our patients by creating a widespread deficiency of a nutrient
critically important to heart function,” writes Dr. Langsjoen.
Dr. Langsjoen joined Dr. Mark Silver of the Heart Failure Institute
at Advocate Christ Medical Center in Oak Lawn, IL, in presenting
a study design for determining whether CoQ10 levels might be used
to measure myocardial diastolic function as an early marker of
ventricular dysfunction.11
They reasoned that statins in-hibit HMG-CoA reductase, the rate-limiting
step that inhibits cholesterol and CoQ10 synthesis in the liver.
Because CoQ10 plays an important role during oxidative phosphorylation
in the myocardial cell, evaluating CoQ10 action on ATP might be
used as an early-warning indicator of potential heart problems.
After a number of baseline cardiovascular and metabolic measurements
are established for each subject, the researchers suggest, they
would receive oral atorvastatin (Lipitor®) of 20 mg per day
for three to six months, with baseline levels repeated after three
and six months of treatment. Patients demonstrating reduced measurement
of diastolic left ventricular function that worsened during the
three to six months of statin therapy would then receive 300 mg
per day for three months, with follow-up echocardiogram and blood
CoQ10 level measurements. The objective would be to see if CoQ10
supplementation could reverse statin-induced heart failure.
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At the University of Texas at Austin’s Biochemical Institute,
researcher Dr. Flora Pettit discovered that CoQ10 may be helpful
in assessing susceptibility to statin toxicity and determining
which patients might benefit from CoQ10 supplementation.
She reported in the journal Drug Metabolism and Drug Interactions that even low levels of statins are toxic to human lymphocytes
in cell cultures, adding that the patient’s own plasma reversed
this toxicity in some instances.12 Adding CoQ10 to plasma, however,
was more effective than plasma alone in reversing cell toxicity
in some of these patients, Pettit and colleagues found.
Coumadin® and CoQ10
While some doctors have suggested that CoQ10 might interfere with the effects
of the popular blood-thinner warfarin (Coumadin“), a trial by Danish
researcher Jyette Engelsen and colleagues, published in the Danish medical
journal Ugeskrift for Laeger, found no association between CoQ10
supplementation (100 mg per day) and the clinical anti-coagulant effect observed
in a group of 24 patients on long-term warfarin
treatment.13
Moreover, the study’s randomized, double-blind, placebo-controlled,
cross-over methodology presents a far more convincing argument
that the risk is minimal. Nevertheless, warfarin patients are advised
to consult their doctors and frequently monitor their blood test
results to assess clotting time (prothrombin time/INR), especially
in the first two weeks (something that is already done in most
cases, the scientists noted).
Muscular Dystrophy
Muscular dystrophy patients receiving CoQ10 therapy showed significantly less
cytogeneic and DNA damage than their untreated counterparts, according to
a study by Dr. Lucia Migliore and colleagues at Pisa University in Italy.
They compared basal levels of nuclear DNA (nDNA) damage as measured by chromosomal
and DNA alterations in leukocytes in 13 patients.14
The subjects, ranging in age from 29 to 74 and presenting with
several forms of muscular dystrophy, were compared with a subgroup
of 10 patients who received a two-week course of ubidecarenone,
a CoQ10 analogue. Untreated muscular dystrophy patients showed
an increased level of chromosomal damage (frequency of micronucleated
lymphocytes) compared with equally matched individuals receiving
CoQ10.
“Patients receiving ubidecare-none showed a statistically
significant reduction in the frequency of micronucleated cells
after therapy, while only a slight decrease was observed in the
levels of both primary DNA damage and oxidized bases,” the
scientists reported in the January 2004 issue of Mutagenesis.
Cancer
Several interesting studies were reported on CoQ10’s effects against
certain cancers. Studying differences between malignant and non-malignant prostate
cancer cells, Dr. Jose L. Quiles and colleagues at the University of Granada,
Spain, found that malignant cells respond very differently to coenzyme Q10.15
CoQ10 supplementation significantly lowered cell growth of the
PC3 cancer line without affecting non-malignant cells. The authors
noted that if the findings are confirmed, they might present a “novel
and interesting” approach using coenzyme Q10 in cancer therapy.
Reproduction
CoQ10 may play a role in the health of sperm cells in fighting male infertility,
according to Dr. Antonio Mancini and colleagues at the Institute of Endocrinology
at Catholic University of the Sacred Heart in Rome, Italy.16
In an earlier study, they found CoQ10 was present in seminal
fluid and directly correlated to sperm motility in infertile men,
with the exception of those with varicocele, a dilation of the
pampiniform venous plexus associated with infertility.
A follow-up published in the journal Metabolism evaluated distribution
of CoQ10 in seminal fluid and plasma in 32 varicocele patients
and healthy male controls in an effort to determine whether any
metabolic abnormalities played a role in various seminal parameters
in varicocele patients.
The researchers reported a significantly higher proportion of
CoQ10 in the seminal fluid of varicocele subjects, with high cellular
CoQ10 levels correlated with low sperm concentration and motility,
suggesting that such patients may be more sensitive to peroxidative
damage and therefore reduced energy utilization that might then
translate into defective motility. Further, the findings might
indicate a possible molecular defect involved in the condition.
Females also demonstrate a reproductive protective benefit. During
preeclampsia, a life-threatening disorder affecting about 7% of
late-stage pregnancies, women suffer edema, hypertension, and proteinuria.
Serum levels of CoQ10 are severely decreased in preeclampsia patients,
reported Dr. Enrique Teran, a scientist at the University of Ecuador
in Quito.17
In a study published in the journal Free Radical and Biological
Medicine, Dr. Teran and his colleagues measured concentrations
of CoQ10 in a group of 18 healthy pregnant women, 12 subjects with
preeclampsia, and 22 women who were not pregnant or hypertensive.
In the normal pregnant women, CoQ10 levels were significantly higher
than in nonpregnant women or those with preeclampsia. The mean
level of CoQ10 was 1.08 in healthy pregnant women, 0.86 in non-pregnant
women, and 0.70 in women with preeclampsia.
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