The ratio of M1 to M2 microglia in the striatum determines the severity of L ‐Dopa‐induced dyskinesias

We report that L-Dopa treatment leading to LIDs exacerbates activated microglia numbers beyond that associated with the PD state; the severity of LIDs is strongly correlated to the ratio of the striatal M1 to M2 microglial numbers; in non-dyskinetic mice, there is no M1/M2 microglia ra tio increase above that seen in PD mice; and reducing M1/M2 microglia ratio using anti-inflammatories is anti-dyskinetic. Parkinson's disease is associated with increased inflammation, but this is insufficient to underpin dyskinesia. Given that L-Dopa-treated non-LID mice show the same ratio of M1/M 2 microglia as PD mice that received no L-Dopa, and, given minocycline/indomethacin reduces both the ratio of M1/M2 microglia and dyskinesia severity, our data suggest the increased microglial M1/M2 ratio that occurs following L-Dopa treatment is a contributing cause of dyskinesias.
Source: Journal of Neurochemistry - Category: Neuroscience Authors: Tags: ORIGINAL ARTICLE Source Type: research