Analgesic and Neurorestorative Effects of αO-Conotoxin GeXIVA[1,2] in Diabetic Neuropathic Pain and Postherpetic Neuralgia

Chronic neuropathic pain, particularly diabetic neuropathic pain and postherpetic neuralgia, severely impairs patients' quality of life due to their complex mechanisms and recurrent, long-term nature, making treatment challenging. This study aimed to evaluate the analgesic efficacy of α-conotoxin GeXIVA[1,2], a selective antagonist of the α9α10 nicotinic acetylcholine receptor (nAChR), in rat models of diabetic neuropathic pain and postherpetic neuralgia and investigate its associated physiological and pathological effects. GeXIVA[1,2] was administered continuously for three weeks, with mechanical hypersensitivity assessed through pain sensitivity tests, and behavioral assessments conducted to examine motor coordination and gait. Additionally, neural tissue structure and inflammation were analyzed. The results demonstrated that GeXIVA[1,2] significantly alleviated mechanical hypersensitivity in both diabetic neuropathic pain and postherpetic neuralgia models, with greater efficacy than gabapentin and no signs of tolerance. Behavioral tests indicated no significant effects on motor coordination or gait. Further analysis revealed that GeXIVA[1,2] reduced pro-inflammatory cytokine levels, decreased immune cell infiltration, and promoted repair of damaged nerve fibers. Overall, these findings suggest that GeXIVA[1,2] exerts analgesic effects through anti-inflammatory and neuroprotective mechanisms, providing a potential new therapeutic strategy for diabetic neuropathic pain and postherpetic neuralgia.