A New Trick Of INPP4A: Decreased Expression Of INPP4A In Patients With Temporal Lobe Epilepsy And Pilocarpine-induced Rat Model

Inositol polyphosphate phosphatase4A (INPP4A), aphosphoinositides phosphatase, is highly expressed in the central nervoussystem and plays a role in glutamate excitotoxicity and cell proliferation.Our aim was to investigate the expression of INPP4A in patients withtemporal lobe epilepsy (TLE) and in a rat model of epilepsy. We assessedthe expression of INPP4A in the temporal neocortex from twenty TLEpatients. The result showed that INPP4A expression was significantlylower in TLE patients than in controls. To validate the results found inTLE patients, we assessed the expression of INPP4A in rat model. Ratepilepsy was induced by lithium-pilocarpine. Expression of INPP4A of ratmodels was assessed by immunohistochemistry, immunofluorescence andWestern blotting. INPP4A was expressed in the membrane and cytoplasmof neurons. In the hippocampus and neocortex of epileptic rats, INPP4Aexpression was first downregulated at the24h after seizures, andmaintained decreased levels at72h,7d,14d,30d and60d, respectively. These results suggest that a decreased expression of INPP4A in the brainmay be associated with TLE.