Experimental Compound Shows Promise for SBMA

A compound known as ASC-J9 has shown remarkable effects in treating spinal-bulbar muscular atrophy (SBMA, or Kennedy’s disease) in mice with the disorder. Mice treated with ASC-J9 dissolved in corn oil and injected into the abdomen every other day showed better motor and sexual function and longer survival than mice treated with a corn oil solution alone. The treatment was effective whether it was given before the onset of symptoms or long after.

SBMA, which affects males almost exclusively, is a disease in which muscle-controlling nerve cells (motor neurons) in the spinal cord and brain stem degenerate. Feminization and impairment of fertility and sexual function may also occur.

The root cause of the disease is an expanded section of DNA in the gene for the androgen receptor, a protein that normally transports male hormones (androgens) inside cells.

The expanded DNA leads to an expanded, sticky androgen receptor protein that forms clumps in the nuclei of nerve and muscle cells. Trapped inside the clumps are a number of proteins that would otherwise regulate various cellular functions.

Zhiming Yang at the University of Rochester (N.Y.) Medical Center and colleagues, who published their results in the March issue of Nature Medicine, say they believe ASC-J9 disrupts this abnormal clumping.

Diane Merry at Thomas Jefferson University, who had MDA support for SBMA research from 2002 through 2005, was part of the research team.