Possible neuroprotective effect of testosterone treatment in men

May 17 2007

A small pilot study suggests that testosterone treatment is safe, well tolerated and may reduce symptoms, slow brain degeneration and increase muscle mass in men with relapsing-remitting multiple sclerosis, the most common form of the disease, according to a report in the May issue of Archives of Neurology.

Multiple sclerosis is a progressive disease involving the immune and central nervous systems. MS and many other autoimmune diseases (in which the body attacks its own systems or tissues) are less common in men than in women, according to background information in the article. This is especially true during reproductive years. Sex hormones, including testosterone and estrogen, may be responsible for the difference. Testosterone has been shown to protect against an MS?like condition and other autoimmune diseases in animals.

Nancy L. Sicotte, M.D., of the David Geffen School of Medicine at UCLA, Los Angeles, and colleagues conducted a study of testosterone treatment in 10 men with relapsing-remitting MS, characterized by periods of neurologic symptoms (such as numbness or difficulty walking) followed by periods of remission. The men, who had an average age of 46, were enrolled in the study and then entered a six-month pre-treatment phase, during which symptoms were monitored but no therapies were administered. Then, each man applied 10 grams of a gel containing 100 milligrams of testosterone to his upper arms once daily for 12 months.

"One year of treatment with testosterone gel was associated with improvement in cognitive performance and a slowing of brain atrophy [deterioration]," the authors write. During the first nine months of the study?the period of time before the men began taking testosterone, plus the first three months of treatment, before it had time to take effect?brain volume decreased an average of -0.81 percent per year. In the second nine months, this decline slowed by 67 percent to an annual rate of -0.25 percent. "Because the protective effect of testosterone treatment on brain atrophy was observed in the absence of an appreciable anti-inflammatory effect, this protection may not be limited to MS, but may be applicable to those with non-inflammatory neurodegenerative diseases," including amyotrophic lateral sclerosis or Lou Gehrig's disease, the authors write.

In addition, lean body mass (muscle mass) increased an average of 1.7 kilograms (about 3.74 pounds) during the treatment phase. Participants did not report any adverse effects, there were no abnormalities in blood tests taken during the trial and the men's prostate examination results remained stable.

"Overall, in this first trial of testosterone treatment in men with relapsing-remitting MS, the treatment was shown to be safe and well tolerated," the authors conclude. "In addition, exploratory findings reported herein suggest a possible neuroprotective effect of testosterone treatment in men, which warrants further investigation."

http://archneur.ama-assn.org/