Huachansu suppresses TRPV1 up-regulation and spinal astrocyte activation to prevent oxaliplatin-induced peripheral neuropathic pain in rats.

Chemotherapy-induced peripheral neuropathic pain (CIPNP) is a major dose- and therapy-limiting side effect that is particularly difficult to treat. Huachansu, an aqueous extract from toad skin, is a widely used anti-cancer natural product in China. Clinical findings have established the safety and effectiveness of Huachansu in combination with chemotherapy to promote the therapeutic efficacy while alleviate the side effects, especially cancer-related pain symptoms. Unfortunately, experimental data on the effects and mechanisms of Huachansu in combination with chemotherapy is not available. In this study, the effects of Huachansu were tested in vivo on a rat model of oxaliplatin-induced CIPNP. The results show, a single injection of Huachansu 2.5 g/kg produced a short-term analgesic effect on pre-established oxaliplatin-induced CIPNP after 60 min, as indicated by decreased mechanical and thermal hypersensitivity in comparison to oxaliplatin-treated rats. Repeated doses of Huachansu, given during CIPNP induction, prevented the development of oxaliplatin-induced CIPNP. This prophylactic effect of Huachansu was associated with suppressed oxaliplatin-induced TRPV1 up-regulation in the dorsal root ganglia and spinal astrocyte activation. These findings reveal Huachansu therapeutic potential in treating and preventing CIPNP.