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Source #1: Proceedings of the National Academy of Sciences 2001;98:14669- Date: 04 december 2001 Source #2: http://news.excite.com/news/r/011126/17/health-mice Date: 26 november 2001 Antibiotic Treats Parkinson's-Like Damage in Mice By Amy Norton NEW YORK (Reuters Health) - A modified tetracycline antibiotic appears to prevent brain cell loss like that seen in Parkinson's disease, according to findings from a study in mice. The drug, called minocycline, prevented degeneration in dopamine-producing brain cells in mice that were made to have a Parkinson's-like disease. Parkinson's is marked by the destruction of brain cells that produce dopamine, a chemical that is a key regulator of muscle movement. "Chemically modified tetracyclines, like minocycline, may prove effective in preventing and/or altering the progression of Parkinson's disease," conclude researchers led by Steven M. Paul of the Indiana University School of Medicine in Indianapolis. Paul also works for the drugmaker Eli Lilly and Company, which funded the study. However, Paul told Reuters Health, the brain damage his team induced in the study mice "certainly doesn't mimic the exact etiology (cause) or pathophysiology (course) of Parkinson's disease." Moreover, he said, the animals required very high doses of oral minocycline for it to protect the brain--doses that may not be "achievable" in patients. If this research can be extended to humans, according to Paul, a better approach would likely be to develop a different tetracycline that "gets into the brain better." His team's report, to be published in the December 4th issue of the Proceedings of the National Academy of Sciences, is being released Tuesday in the journal's early online edition. Parkinson's disease is a motor system disorder in which patients experience tremors, muscle rigidity, impaired movement, and problems with balance and coordination. Treatment includes drugs that replace the brain's dwindling supply of dopamine, but there is no cure for the progressive loss of dopamine-producing brain cells. In their study, Paul and his colleagues treated mice with MPTP, a toxic chemical that induces parkinsonian symptoms in animals and humans. Groups of mice were treated with minocycline before, during and after receiving MPTP. Some mice did not receive the antibiotic. The investigators found that at high doses, the drug was able to protect many dopamine cells from damage when it was given either before or after MPTP. Similarly, the researchers note, a recent study showed that minocycline delayed death in mice made to show characteristics of Huntington's disease, a genetic disorder that is also marked by brain cell degeneration. According to Paul, minocycline may prevent dopamine-cell damage by blocking the action of nitric oxide (NO) in the brain. Some research has suggested that the release of NO from activated brain cells called glial cells is involved in the degeneration seen in Parkinson's. This remains only speculation, however. Whatever the reason, minocycline seems to have "neuroprotective effects...quite apart from its antibiotic properties," Paul said. If a tetracycline like it does prove useful against Parkinson's, he noted, it would ideally have its antibiotic capacity somehow extracted since it is unneeded and could have untoward effects in patients. ---------------------------------------------------------------------- To sign-off Parkinsn send a message to: mailto:[log in to unmask] In the body of the message put: signoff parkinsn