Neuro-therapeutic effect of ursolic acid in a murine model of vincristine-induced neuropathic pain
摘要
Neuropathic pain is a chronic pain caused by the damage or dysfunction of the somatosensory system, which results in abnormal signaling and processing of pain signals. It is a debilitating condition often associated with chemotherapy. Ursolic acid, a triterpene of natural origin, possesses anti-inflammatory, antioxidant, and anti-nociceptive effects, making it worth being explored as potential therapy for neuropathic pain. The current study aimed to investigate the potential neuroprotective effect of ursolic acid in vincristine-induced neuropathic pain. Rats were given ursolic acid (5, 10 and 30 mg kg−1 p.o.) or gabapentin (10, 30, and 100 mg kg−1 i.p.) after 10 days of vincristine administration. Behavioral assessments of tactile and cold allodynia, as well thermal and mechanical hyperalgesia were done hourly for 4 h after treatment with ursolic acid or gabapentin. The sciatic nerve was isolated for biochemical analysis of oxidative stress markers and pro-inflammatory cytokines. All doses of ursolic acid significantly attenuated tactile and cold allodynia as well as thermal and mechanical hyperalgesia. Biochemical analysis of sciatic nerve preparation also showed significant (P < 0.05) decrease in the levels of oxidative stress markers (SOD, CAT and MDA). ursolic acid treatment also caused a significant (P < 0.05) reduction in pro-inflammatory cytokines such as TNF-α and IL -1β, as well as iNOS and p38 MAPK. Ursolic acid attenuated allodynia and hyperalgesia induced by vincristine administration and the study also evidently provides grounds for development of ursolic acid as a drug candidate for the management of neuropathic pain.