Tuesday, October 30, 2007

Too much of a good thing: When testosterone is bad for muscles

has anybody asked certain profesional athletes about this?

EAST LANSING, Mich. — A mouse created by Michigan State University scientists studying a disease thought to be a neurological disorder that weakens men has exposed two surprises: Testosterone appears to be the culprit and it’s attacking muscles, not nerves.

The muscles of male mice genetically engineered in the laboratory of Cynthia Jordan, professor of neuroscience and psychology, have extra receptors that latch onto testosterone – a trick that left researchers anticipating mouse versions of bulked up body builders. Instead, these mice developed into shrunken weaklings. More significantly, their condition precisely imitated a rare human condition called Kennedy’s Disease.

The results, reported in the Oct. 29 online issue of the Proceedings of the National Academy of Sciences, not only directly contradict conventional wisdom about the root of Kennedy’s Disease, but also offer significant hope. Researchers say these new results make a strong case that Kennedy’s Disease is a muscular disease rather than a neurological disease, and put testosterone in the category of cause, not cure.

“When we started studying this little wimp mouse, we were surprised to find that we inadvertently created a model for Kennedy’s Disease,” Jordan said. “Our story provides some hope, because it’s an easier problem to target muscles therapeutically than the motor neurons in the spinal cord. Our sick mice get well when we take testosterone away from them.”

link to full article

1 comment:

Charles Lin M.D. said...

Interesting article on testosterone.
Too much testosterone can also lead to damage of brain cells. Again , pointing to the very visible spectrum of a healthy range of testosterone. Clearly this goes beyond.