progression of a group of neurodegenerative disorders including multiple sclerosis, rheumatoid arthritis, Huntington's disease, and Parkinson's disease. As mentioned above, minocycline harms ALS patients. Minocycline is also known to indirectly inhibit inducible nitric oxide synthase. A trial found no difference between minocycline and placebo in people with Alzheimers' disease. Minocycline also has been used as a "last-ditch" treatment for toxoplasmosis in AIDS patients. Minocycline is somewhat neuroprotective in mouse models of Huntington's disease. A 2007 study reported the impact of the antibiotic minocycline on clinical and magnetic resonance imaging (MRI) outcomes and serum immune molecules in 40 MS patients over 24 months of open-label minocycline treatment. Despite a moderately high pretreatment relapse rate in the patient group prior to treatment (1.3/year pre-enrollment; 1.2/year during a three-month baseline period), no relapses occurred between months 6 and 24 on minocycline. Also, despite significant MRI disease-activity pretreatment (19/40 scans had gadolinium-enhancing activity during a three-month run-in), the only patient with gadolinium-enhancing lesions on MRI at 12 and 24 months was on half-dose minocycline. Levels of interleukin-12 (IL-12), which at high levels might antagonize the proinflammatory IL-12 receptor, were elevated over 18 months of treatment, as were levels of soluble vascular cell adhesion molecule-1 (VCAM-1). The activity of matrix metalloproteinase-9 was decreased by treatment. Clinical and MRI outcomes in this study were supported by systemic immunological changes and call for further investigation of minocycline in MS. The overall antidepressant effect size of minocycline compared to placebo in a meta-analysis was -0.78, indicative of a potential antidepressant effect. In ongoing research and trial minocycline demonstrated efficacy and seems a promising neuroprotective agent in acute stroke patients, especially in AIS subgroup. Further RCTs are needed to evaluate the efficacy and safety of minocycline among ICH patients. Data from cellular and animal models PARP1 inhibition Ki = 13.8 nM Neuroprotection IC50 = 10 nM Microglia full inhibition = 20 nM Suppression of the mouse's locomotor activity = 0.5 mg/kg References External links Anti-acne preparations Anti-inflammatory agents Hepatotoxins Neuroprotective agents NMDA receptor antagonists PARP inhibitors Tetracycline antibiotics Triketones Disease-modifying antirheumatic drugs Wikipedia medicine articles ready to translate