Vinpocetine attenuates methotrexate-induced hippocampal intoxication via Keap-1/Nrf2, NF-κB/AP-1, and apoptotic pathways in rats.

Methotrexate (MTX) is an anti-folate chemotherapeutic commonly used to treat cancer and autoimmune diseases. Despite its widespread clinical use, MTX has been linked to serious neurotoxicity side effects. Vinpocetine (VNP) has been widely used clinically to treat many neurological conditions. This study was conducted to study the potential neuroprotective effects of VNP against MTX hippocampal intoxication in rats. Thirty-two rats were randomly allocated into 4 groups: (I) control (Vehicle); (II) VNP-treated group (20 mg/kg/day, p.o); (III) MTX-control (20 mg/kg/once, i.p.) group; and (IV) the VNP + MTX group. VNP was administered orally for 10 days, during which MTX was given intraperitoneally once at the end of day 5. Our data indicated that VNP administration significantly improved MTX-induced neuronal cell death, odema, vacuolation and degeneration. VNP attenuated oxidative injury mediated by significant upregulation of the Nrf2, HO-1, and GCLC genes, while the Keap-1 mRNA expression downregulated. Moreover, VNP suppressed cytokines release mediated by increasing IκB expression level while it caused a marked downregulation in NF-κB and AP-1 (C-FOS and C-JUN) levels. Additionally, VNP attenuated apoptosis by reducing hippocampal Bax levels while increasing Bcl2 levels in MTX-intoxicated rats. In conclusion, our results suggested that VNP significantly attenuated MTX hippocampal intoxication by regulating Keap-1/Nrf2, NF-κB/AP-1, and apoptosis signaling in these effects.