P-1 Potential neuroprotective effects of losartan and donepezil on oxaliplatin-induced peripheral neuropathy in rats

Oxaliplatin (OXL) is a platinum-based antineoplastic drug widely used for treating colorectal cancer which induces peripheral neuropathy as dose-limiting toxicity. We assess the neuroprotective effects of losartan (LOS) and donepezil (DPZ) on OXL-induced peripheral neuropathy in rats. Forty Sprague-Dawley rats were divided into four groups; control (vehicle-treated), OXL (2.4 mg/kg/d; intraperitoneal), OXL+LOS (100 mg/kg/d; oral), and OXL+DPZ (1 mg/kg/d; oral). All were given 5 times/week for 2 weeks. Behavioral assessment of pain, sensory, and motor disturbances was done on days 7 and 14 using a paintbrush, acetone, tail-flick latency, and grip strength tests. The levels of interleukin (IL)-1β, and tumor necrosis factor (TNF)-α were measured in L4-L6 samples. Histopathological examination of the sciatic nerve was done to assess nerve degeneration. OXL induced significant mechanical dynamic allodynia, cold allodynia, and thermal hyperalgesia compared to the control group. LOS significantly ameliorated mechanical and cold allodynia, while DPZ improved mechanical allodynia and thermal hyperalgesia. OXL significantly increased IL-1β, and TNF-α compared to the control group. Only LOS significantly attenuated these markers. In the OXL group, the axons were swollen, and nerve fiber degeneration with neuron gaps occurred. Both treatments improved these histopathological changes. LOS and DPZ attenuate the neurotoxic effect of oxaliplatin by attenuating behavioral and histopathological alterations and the protective effect of LOS may involve in the inhibition of spinal pro inflammatory cytokines. Therefore, LOS and DPZ are promising agents to prevent OXA-induced peripheral neuropathy.