The Traf2 and NcK interacting kinase inhibitor NCB-0846 suppresses seizure activity involving the decrease of GRIA1
Epilepsy, a common neurological disorder, is characterized by spontaneous and recurrent seizures. Temporal lobe epilepsy (TLE) is one of the most prevalent forms of medically refractory epilepsy. Traf2-and NcK-interacting kinase (TNIK) has recently gained attention as a key modulator in several neurological and psychiatric disorders, but its role in epilepsy remains poorly understood. In this study, we hypothesized that TNIK plays a significant role in epilepsy and investigated its expression in patients with intractable TLE as well as in a pilocarpine-induced rat model of epilepsy. TNIK expression was analyzed using western blotting, immunofluorescence, and immunohistochemistry. We also utilized a pentylenetetrazole (PTZ)-induced rat epilepsy model to evaluate the effects of the TNIK inhibitor NCB-0846 on behavioral manifestations of epilepsy. Co-immunoprecipitation (Co-IP) and mass spectrometry (MS) were employed to explore the potential molecular mechanisms underlying TNIK’s involvement in epilepsy.
Our results showed that TNIK was primarily localized to neurons, with significant reductions observed in both the epilepsy rat model and TLE patient samples compared to controls. Treatment with NCB-0846 delayed the progression of kindling and reduced the severity of seizures in the epilepsy models. Co-IP/MS identified 63 candidate interactors of TNIK in the rat hippocampus, including the key protein CaMKII. Further Co-IP analysis revealed that TNIK may interact with several important proteins, such as GRIA1, SYN2, PSD-95, CaMKIV, GABRG1, and GABRG2. Additionally, we observed a significant decrease in GRIA1 expression in both the total hippocampal lysates and postsynaptic density (PSD) fractions after NCB-0846 treatment, which may help modulate the progression of PTZ-induced kindling.
These findings suggest that TNIK plays a crucial role in the pathophysiology of epilepsy and may represent a promising target for the development of new antiepileptic therapies.