a Department of Orthopaedics , The Second Affiliated Hospital of Nanchang University , Nanchang , PR China.
b Class 152 of Prevention , Grade 2015, School of Public Health of Nanchang University , Nanchang , PR China.
Int J Neurosci. 2019 Aug;129(8):784-793. doi: 10.1080/00207454.2019.1567512. Epub 2019 Feb 18.
This study investigated whether the neuronal P2X3 receptor in rat dorsal root ganglia (DRG) mediated the effects of hesperidin on neuropathic pain. The chronic constriction injury (CCI) model was used as a model of neuropathic pain. The mechanical withdrawal threshold (MWT) and thermal withdrawal latency (TWL) were measured. The mRNA and protein expression levels were assayed by real-time RT-PCR and Western blotting. The results showed that mechanical and thermal hyperalgesia in the CCI rats were increased as compared to those in the sham group. The expression levels of P2X3 mRNA and protein in CCI rats were higher than those in the sham group. Dual-labelling immunofluorescence showed that the elevated P2X3 receptor was co-expressed with the neuronal marker NeuN in the DRG of CCI rats. Hesperidin treatment decreased both the mechanical and thermal hyperalgesia, and upregulated P2X3 expression in the CCI rats. Hesperidin treatment also reduced the ERK1/2 phosphorylation in the DRG of CCI rats. Moreover, hesperidin inhibited the P2X3 agonist ATP-induced currents in HEK293 cells transfected with the P2X3 plasmid. Therefore, hesperidin treatment could reverse the elevated expression of neuronal P2X3 receptor and reduce the activation of ERK1/2 in the DRG of CCI rats. Our findings suggested that hesperidin inhibited the nociceptive transmission mediated by the P2X3 receptor in neurons of DRG, and thus, relieved the mechanical and thermal hyperalgesia in CCI rats.
本研究旨在探讨大鼠背根神经节(DRG)神经元 P2X3 受体是否介导了橙皮苷对神经病理性疼痛的作用。采用慢性压迫损伤(CCI)模型作为神经病理性疼痛模型。测量机械缩足反射阈值(MWT)和热缩足潜伏期(TWL)。通过实时 RT-PCR 和 Western blot 测定 mRNA 和蛋白表达水平。结果表明,与假手术组相比,CCI 大鼠的机械和热痛觉过敏增加。CCI 大鼠 P2X3 mRNA 和蛋白的表达水平高于假手术组。双重免疫荧光显示,DRG 中升高的 P2X3 受体与神经元标志物 NeuN 共表达。橙皮苷治疗降低了 CCI 大鼠的机械和热痛觉过敏,并上调了 P2X3 的表达。橙皮苷治疗还降低了 CCI 大鼠 DRG 中 ERK1/2 的磷酸化。此外,橙皮苷抑制了转染 P2X3 质粒的 HEK293 细胞中 P2X3 激动剂 ATP 诱导的电流。因此,橙皮苷治疗可逆转 CCI 大鼠 DRG 中神经元 P2X3 受体的高表达,并降低 ERK1/2 的激活。我们的研究结果表明,橙皮苷抑制了 DRG 神经元中 P2X3 受体介导的伤害性传递,从而缓解了 CCI 大鼠的机械和热痛觉过敏。