Melinda T. Willis

Q10, a commonly available dietary supplement, may soon be on many more people's lips … literally.

A powerful over-the-counter antioxidant, coenzyme Q10 has demonstrated significant potential in several disease areas from cardiology to cataracts to cancer. And now new research suggests it could help bring new hope to those with Parkinson's, the devastating neurodegenerative disease.

A study published in the journal Archives of Neurology suggests that coenzyme Q10 may be able to accomplish what current treatments for Parkinson's disease cannot; slow its progression. The ailment afflicts between one-million and 1½ million Americans with 50,000 new cases reported every year.

Coenzyme Q10 is a naturally occurring compound produced by the body that works by neutralizing molecules known as free radicals. Free radicals are present in high levels in the energy-producing components of cells and can cause cell damage and death.

In Parkinson's disease, research has shown that this free radical damage is greater in the area of the brain responsible for movement control, which leads to cell death and development of the disease.

In the latest research, 80 Parkinson's sufferers were randomly assigned to receive coenzyme Q10 at three different doses, or a placebo. The progressive deterioration in movement that characterizes the disease was slowed by 44 percent in those who took the highest doses.

"There's really no treatment that has been shown unequivocally to slow the progression of the disease," says Dr. Clifford Shults, lead author of the study and professor of neurosciences at the University of California, San Diego. "Our data suggests that coenzyme Q10 may, but it clearly needs to be confirmed and extended."

Marcia Buck, a clinical pharmacy specialist at the University of Virginia in Charlottesville agrees. "This is the first study, to my knowledge, of this size for this indication...but the sample size is still too small to make many conclusions."

Neurodegenerative Disease Breakthrough?

Parkinson's is not the only neurodegenerative ailment for which coenzyme Q10's antioxidant effects may have an application.

In one recent trial published in the journal Neurology, Q10 was shown to have a 14 percent effect in slowing the progression of Huntington's disease. While this finding did not achieve statistical significance, it was viewed as encouraging nonetheless.

"The maximum dose was 600 milligrams per day," explains Dr. Flint Beal, professor and chair of neurology at the Weill Medical College of Cornell University in New York. "The dose that was used in the Parkinson's trial that shows the biggest effect is 1,200 milligrams per day. So it's conceivable that using a higher dose in Huntington's disease might have a bigger effect."

Q10 has shown small significant benefit in treating ALS, also known as Lou Gehrig's disease, and it has also has been used to treat a range of rare pediatric neurological diseases.

And while no research has been conducted to date, theoretical evidence suggests that coenzyme Q10 may help treat Alzheimer's disease. "From a conceptual standpoint, it is very reasonable to hypothesize that it could potentially be beneficial, particularly in view of this evidence from Parkinson's disease," adds Beal.

Putting the Heart First

Coenzyme Q10 has been available over the counter in the United States for about a decade, largely due to studies conducted on its potential to strengthen failing hearts. Most of the research in this area has been conducted abroad, but a small number of U.S. trials exist.

A six-year long study conducted by researchers at Scott and White Hospital in Temple, Texas, explored the use of Q10 in 126 heart failure patients in the early 1980s to find out whether the already established potential of Q10 in healing hearts could be sustained.

"They did great," says Dr. Peter Langsjoen, a cardiologist in private practice in Tyler, Texas, who conducted the study. "The improvement in heart function was sustained and if anything, the mortality was about a third of what was expected."

Heart muscle, because it is in constant motion, is high in Q10. Although it is not well understood, levels of Q10 decrease as people age and can be depleted even further when the heart muscle is damaged.

Despite its theoretical potential, American cardiologists have yet to embrace Q10 as the answer to treating heart failure.

"The safety and effectiveness of Co-Q10 need to be further evaluated," says the American Heart Association. "This requires conducting well-designed clinical trials involving large numbers of patients over a long time. Until that happens, the American Heart Association cannot recommend taking coenzyme Q10 regularly."

No Drugstore Rush Just Yet

Because any disease process that involves free radical damage could be treated with coenzyme Q10, the theoretical therapeutic potential of this compound seems limitless. Cataracts, macular degeneration, side effects of chemotherapy and skin damage related to radiation exposure could all be helped by doses of Q10, proponents believe.

Coenzyme Q10 is also remarkably well tolerated, with few side effects noted in many trials that have studied its use. But whether you should rush to the drug store to pick up a bottle is harder to say.

Some physicians worry the supplement's full range of side-effects is unknown because it hasn't been the subject of enough research. Others are concerned about the proper dosage and the possibility of drug interactions.

Despite these cautions, physicians say they already have patients who are taking Q10 and expect to see an increase in interest in it.

"It is highly likely that my patients will hear of this and start on Q10," says Dr. Neil H. Brooks, a primary care physician from Vernon, Conn.

Rather than stimulating a rush on Q10 by the public, some hope that new research will spark interest in funding studies to test Q10 more rigorously and identify the doses and preparations that are of most benefit, if at all.

This is especially important for those researching neurodegenerative diseases for which few current treatments exist.

Says Michael Miles, a professor of clinical pediatrics and neurology at Cincinnati Children's Hospital in Ohio, "We'll actually find out whether Q10 or some combination of Q10 with other agents may really help give some of these patients a little hope for the future."

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