Fei Xu1, Youhan Li2, Shuo Li3, Yunqing Ma4, Ning Zhao5, Yong Liu6, Niansong Qian7, Hong Zhao8, Yu Li9. 1. Department of Radiation Oncology, PLA 302 Hospital, Beijing, China. 2. Department of Clinical Laboratory, PLA 302 Hospital, Beijing, China. 3. Department of Medical Branch, PLA 302 Hospital, Beijing, China. 4. Department of Osteology, PLA 304 Hospital, Beijing, China. 5. Department of Medical Branch, Air force General Hospital, Beijing, China. 6. Department of Ophthalmology, Naval General Hospital, Beijing, China. 7. Department of Oncology, Hainan branch of PLA General Hospital, Beijing, China. Electronic address: qianniansong1@163.com. 8. Department of Oncology, Hainan branch of PLA General Hospital, Beijing, China. Electronic address: zhh301@sina.com. 9. Department of Radiation Oncology, PLA 302 Hospital, Beijing, China. Electronic address: 326308005@qq.com.
Abstract
BACKGROUND: Inflammatory pain is one of the most common clinical symptoms, mechanical allodynia and thermal hypersensitivities are associated with proinflammatory cytokines, and proinflammatory cytokine antagonists could alleviate the hypersensitivity. Previous studies showed that a traditional Chinese medicine ingredient, triptolide could inhibit inflammatory cytokines; however, it was still unknown whether triptolide had beneficial effects on treating inflammatory pain. MATERIALS AND METHODS: The effects of triptolide on Complete Freund's Adjuvant-induced acute inflammatory pain were investigated using behavioral tests. The activation of spinal glia was morphologically observed by immunofluorescent histochemistry. The levels of OX42, glia fibrillary acidic protein, and phosphorylated extracellular signal-regulated kinase in the spinal cord were detected by Western blot, and the messenger RNA levels of interleukin 1β, interleukin 6, and tumor necrosis factor alpha were detected by real-time polymerase chain reaction. RESULTS: These results demonstrate that the triptolide effectively attenuates inflammatory pain induced by Complete Freund's Adjuvant, the underlying mechanism may regulate the phosphorylated extracellular signal-regulated kinase signaling pathway and inhibit the spinal glia activation, and then downregulate the proinflammatory cytokines; the triptolide may be clinically useful as a drug of anti-inflammatory pain. CONCLUSIONS: In the present study, we first reported that repeated systemic administration of triptolide could safely prevent and reverse inflammatory pain. The triptolide may serve as a new potential compound for developing safe therapeutics for patients suffering inflammatory pain.
BACKGROUND:Inflammatory pain is one of the most common clinical symptoms, mechanical allodynia and thermal hypersensitivities are associated with proinflammatory cytokines, and proinflammatory cytokine antagonists could alleviate the hypersensitivity. Previous studies showed that a traditional Chinese medicine ingredient, triptolide could inhibit inflammatory cytokines; however, it was still unknown whether triptolide had beneficial effects on treating inflammatory pain. MATERIALS AND METHODS: The effects of triptolide on Complete Freund's Adjuvant-induced acute inflammatory pain were investigated using behavioral tests. The activation of spinal glia was morphologically observed by immunofluorescent histochemistry. The levels of OX42, glia fibrillary acidic protein, and phosphorylated extracellular signal-regulated kinase in the spinal cord were detected by Western blot, and the messenger RNA levels of interleukin 1β, interleukin 6, and tumor necrosis factor alpha were detected by real-time polymerase chain reaction. RESULTS: These results demonstrate that the triptolide effectively attenuates inflammatory pain induced by Complete Freund's Adjuvant, the underlying mechanism may regulate the phosphorylated extracellular signal-regulated kinase signaling pathway and inhibit the spinal glia activation, and then downregulate the proinflammatory cytokines; the triptolide may be clinically useful as a drug of anti-inflammatory pain. CONCLUSIONS: In the present study, we first reported that repeated systemic administration of triptolide could safely prevent and reverse inflammatory pain. The triptolide may serve as a new potential compound for developing safe therapeutics for patients suffering inflammatory pain.