University of California-Irvine researchers found mice genetically engineered to have inclusion body myositis, or IBM -- a skeletal muscle disease that affects older people -- demonstrated markedly better motor function six months after receiving daily doses of lithium chloride, compared with non-treated mice.

The scientists found muscles in treated mice also had lower levels of a protein that the study linked with muscle inflammation associated with IBM.

"Lithium chloride is an approved drug for treating humans. We already know it is safe and can be used by people," said Professor Frank LaFerla, co-author of the study. "Given our findings, we believe a clinical trial that tests the effectiveness of lithium chloride on IBM patients should be conducted as soon as possible."

IBM is the most common skeletal muscle disorder among people older than 50, the researchers said, noting there is no cure or effective treatment for the disorder.

Results of the study, which included researchers Masashi Kitazawa and Dan Trinh, appear online in the journal Annals of Neurology.