Increased expression of WNK3 in dispersed granule cells in hippocampal sclerosis of mesial temporal lobe epilepsy patients

•We examined the expressional change of WNK3 on GCD of TLE patients with HS.•WNK3 expression significantly enhanced in dispersed dentate granule neurons.•The control of WNK3 may be a novel therapeutic target against epileptic processes. Granule cell dispersion (GCD) is a common neuropathological feature of hippocampal sclerosis (HS) in patients with temporal lobe epilepsy (TLE). However, the underlying molecular mechanism of GCD formation remains unclear. The present study aimed to investigate the expressional changes of With No Lysine protein kinase subtype 3 (WNK3), a molecule upstream of cation-chloride cotransporters with reciprocal expression in sclerosed hippocampus of TLE patients. Using immunofluorescence staining, we analyzed WNK3 immunoreactivity in hippocampal specimens from histologically normal controls and TLE patients with HS. Our results showed that WNK3 expression was significantly increased in dispersed granule neurons in hippocampal tissues from patients with TLE compared with histologically normal hippocampus. These findings demonstrate a potential association between an increased expression of WNK3 and GCD formation during the chronic phase of epilepsy. Controlling WNK3 expression may thus be a novel therapeutic target in epileptogenesis.