RT Journal Article SR Electronic T1 LRRK2 Inhibition Attenuates Microglial Inflammatory Responses JF The Journal of Neuroscience JO J. Neurosci. FD Society for Neuroscience SP 1602 OP 1611 DO 10.1523/JNEUROSCI.5601-11.2012 VO 32 IS 5 A1 Mark S. Moehle A1 Philip J. Webber A1 Tonia Tse A1 Nour Sukar A1 David G. Standaert A1 Tara M. DeSilva A1 Rita M. Cowell A1 Andrew B. West YR 2012 UL http://www.jneurosci.org/content/32/5/1602.abstract AB Missense mutations in leucine-rich repeat kinase 2 (LRRK2) cause late-onset Parkinson's disease (PD), and common genetic variation in LRRK2 modifies susceptibility to Crohn's disease and leprosy. High levels of LRRK2 expression in peripheral monocytes and macrophages suggest a role for LRRK2 in these cells, yet little is known about LRRK2 expression and function in immune cells of the brain. Here, we demonstrate a role for LRRK2 in mediating microglial proinflammatory responses and morphology. In a murine model of neuroinflammation, we observe robust induction of LRRK2 in microglia. Experiments with toll-like receptor 4 (TLR4)-stimulated rat primary microglia show that inflammation increases LRRK2 activity and expression, while inhibition of LRRK2 kinase activity or knockdown of protein attenuates TNFα secretion and nitric oxide synthase (iNOS) induction. LRRK2 inhibition blocks TLR4 stimulated microglial process outgrowth and impairs ADP stimulated microglial chemotaxis. However, actin inhibitors that phenocopy inhibition of process outgrowth and chemotaxis fail to modify TLR4 stimulation of TNFα secretion and inducible iNOS induction, suggesting that LRRK2 acts upstream of cytoskeleton control as a stress-responsive kinase. These data demonstrate LRRK2 in regulating responses in immune cells of the brain and further implicate microglial involvement in late-onset PD.