Retigabine ameliorates CRS-induced depressive-like behaviors and cognitive impairment by inhibiting endoplasmic reticulum stress-mediated apoptosis

BACKGROUND: Retigabine (RTG) shows notable neuroprotective efficacy in multiple brain injury models; however, its interplay with endoplasmic reticulum stress (ERS) is poorly understood. This study was designed to explore the therapeutic potential of RTG against CRS-induced depression-like behaviors and cognitive deficits in mice and to uncover the associated molecular mechanisms. METHODS: A depression-like and cognitive impairment model was established in C57BL/6 male mice using chronic restraint stress (CRS). Six-week-old C57BL/6 male mice were randomly assigned to the following groups: control (Con), model (CRS), RTG (10 mg/kg), XE-991 (2 mg/kg) or tunicamycin (Tm, 2 mg/kg). Behavioral tests were conducted to assess depression-like behaviors and cognitive function. Hippocampal neuronal morphology was examined by H&E and immunofluorescence staining, while changes in endoplasmic reticulum stress (ERS)-related signaling pathways were analyzed by Western blot. RESULTS: Retigabine treatment reduced hippocampal neuronal damage and the expression of ERS-related factors (GRP78, CHOP) and the pro-apoptotic factor BAX in CRS-induced mice, while it increased the levels of BDNF. These effects were antagonized by XE-991 and the ERS agonist tunicamycin (Tm). CONCLUSIONS: Retigabine may alleviate CRS-induced depressive-like behaviors and cognitive impairment by inhibiting ERS-mediated apoptosis, suggesting its potential as a novel therapeutic strategy for depression.