Objective:To investigate whether the activation of p38MAPK is involved in the neuropathic pain induced by P2X4 receptor,and the effects of activated P2X4 receptor and p38MAPK on expression of brain-derived neurotrophi...Objective:To investigate whether the activation of p38MAPK is involved in the neuropathic pain induced by P2X4 receptor,and the effects of activated P2X4 receptor and p38MAPK on expression of brain-derived neurotrophic factor (BDNF) in the chronic neuropathic pain.Methods:Lumbar intrathecal catheters were chronically implanted in male Sprague-Dawley rats.The right sciatic nerve was loosely ligated proximal to the sciatica's trifurcation at approximately 1.0 mm intervals with 4-0 silk sutures.The microglia inhibitor minocycline,P2X4 antagonist (TNP-ATP) and p38MAPK inhibitor (SB203580) were intrathecally administered every 12 h,3 d post-chronic constriction injury (CCI).Mechanical nociceptive thresholds were assessed with the paw withdrawal threshold (PWT) to von Frey filaments.The expression of P2X4 and BDNF were assessed by both immunohistochemical analysis and RT-PCR.Results:Intrathecal injection of minocycline or TNP-ATP or SB203580 significantly attenuated CCI-induced mechanical allodynia.The time courses of P2X4 receptor and BDNF expression were increased at all points after CCI and reached a peak level on postoperative d 7.Intrathecal injection of minocycline or TNP-ATP or SB203580 markedly suppressed the increase of CCI-induced P2X4 receptor and BDNF expression in the spinal cord.Conclusion:The activation of P2X4 receptor BDNF pathways contributes to neuropathic pain in CCI rats,and the activation of p38MAPK is involved in the neuropathic pain induced by P2X4 receptor.展开更多
Applying a stimulating current to acupoints through acupuncture needles–known as electroacupuncture–has the potential to produce analgesic effects in human subjects and experimental animals. When acupuncture was app...Applying a stimulating current to acupoints through acupuncture needles–known as electroacupuncture–has the potential to produce analgesic effects in human subjects and experimental animals. When acupuncture was applied in a rat model, adenosine 5-triphosphate disodium in the extracellular space was broken down into adenosine, which in turn inhibited pain transmission by means of an adenosine A1 receptor-dependent process. Direct injection of an adenosine A1 receptor agonist enhanced the analgesic effect of acupuncture. The analgesic effect of acupuncture appears to be mediated by activation of A1 receptors located on ascending nerves. In neuropathic pain, there is upregulation of P2X purinoceptor 3 (P2X3) receptor expression in dorsal root ganglion neurons. Conversely, the onset of mechanical hyperalgesia was diminished and established hyperalgesia was significantly reversed when P2X3 receptor expression was downregulated. The pathways upon which electroacupuncture appear to act are interwoven with pain pathways, and electroacupuncture stimuli converge with impulses originating from painful areas. Electroacupuncture may act via purinergic A1 and P2X3 receptors simultaneously to induce an analgesic effect on neuropathic pain.展开更多
Schwann cell transplantation is a promising method to promote neural repair, and can be used for peripheral nerve protection and myelination. Microcapsule technology largely mitigates immune rejection of transplanted ...Schwann cell transplantation is a promising method to promote neural repair, and can be used for peripheral nerve protection and myelination. Microcapsule technology largely mitigates immune rejection of transplanted cells. We previously showed that microencapsulated olfactory ensheathing cells can reduce neuropathic pain and we hypothesized that microencapsulated Schwann cells can also inhibit neuropathic pain. Rat Schwann cells were cultured by subculture and then microencapsulated and were tested using a rat chronic constriction injury(CCI) neuropathic pain model. CCI rats were treated with Schwann cells or microencapsulated Schwann cells and were compared with sham and CCI groups. Mechanical withdrawal threshold and thermal withdrawal latency were assessed preoperatively and at 1, 3, 5, 7, 9, 11 and 14 days postoperatively. The expression of P2X3 receptors in L4-5 dorsal root ganglia of the different groups was detected by double-label immunofluorescence on day 14 after surgery. Compared with the chronic constriction injury group, mechanical withdrawal threshold and thermal withdrawal latency were higher, but the expression of P2X3 receptors was remarkably decreased in rats treated with Schwann cells and microencapsulated Schwann cells, especially in the rats transplanted with microencapsulated Schwann cells. The above data show that microencapsulated Schwann cell transplantation inhibits P2X3 receptor expression in L4-5 dorsal root ganglia and neuropathic pain.展开更多
Objective: When nerve injury or inflammatory injury, different miRNA-mediated signal pathways are activated or inactivated, causing pain or hyperalgesia. Therefore, miRNA has become a new direction of pain mechanism r...Objective: When nerve injury or inflammatory injury, different miRNA-mediated signal pathways are activated or inactivated, causing pain or hyperalgesia. Therefore, miRNA has become a new direction of pain mechanism research. We aimed to investigate the effect and mechanism of miR-362-3p on neuropathic pain in rats with chronic sciatic nerve injury (CCI). Methods: Neuropathic pain CCI rat model was established. Real-time-quantitative polymerase chain reaction (RT-PCR), Western blot, immunofluorescence, intrathecal injection, Enzyme-linked immunosorbent assay (ELISA), and dual luciferase reporter gene assays were used to explore the role of miR-362-3p in neuropathic pain development and the relationship between miR-362-3p and JMJD1A (Jumonji domain-containing 1A). Results: In the CCI group, the miR-362-3p level was increased and JMJD1A level was reduced in spinal cords and isolated microglia. The paw withdrawal threshold (PWT) and paw withdrawal latency (PWL) values were increased, the secretion of inflammatory factors was reduced, and the microglial marker Iba1 expression was decreased after intrathecal administration of miR-362-3p. miR-362-3p was observed to target JMJD1A. JMJD1A elevation abolished the inhibitory effects of miR-362-3p on neuropathic pain development. Conclusion: Intrathecal administration of miR-362-3p significantly relieved neuropathic pain in CCI rats and inhibited neuroinflammation possibly through regulating JMJD1A.展开更多
Objective: To observe the effects of p38 mitogen activated protein kinase (MAPK) inhibitor SB203580 by intrathecal injection on the pain behavior and the spinal proinflammatory cytokines in a rat model of bone canc...Objective: To observe the effects of p38 mitogen activated protein kinase (MAPK) inhibitor SB203580 by intrathecal injection on the pain behavior and the spinal proinflammatory cytokines in a rat model of bone cancer pain induced by breast cancer cells. Methods: Eleven rats were used to establish the models of bone cancer pain, six rats were treated by intrathecal SB203580 injection, and the other 5 were as the controls. The paw withdrawal latency (PWL), histology and the spinal levels of IL-1β and TNF-α were detected. Results: All the 11 rats presented evident bone destruction and thermal hyperalgesia after intra-tibial injection of breast cancer cells. No effect of SB203580 on the bone destruction was observed. However, following intrathecal injection of SB203580, the left PWLs (12.12± 1.26 s at 16 days and 12.99 ± 1.65 s at 19 days) were significant higher than that of controls (9.05 ± 1.08 s at 16 days and 8.55 ± 1.60 s at 19 days), P 〈 0.05. Meanwhile, inkathecal injection of SB203580 evidently reduced the levels of spinal IL-1β and TNF-α. Conclusion: Intrathecal injection of SB203580 in a rat model of bone cancer pain cannot prevent the tibial destruction but significantly depress the thermalgia sensitivity, which might result from inhibiting inkacellular p38 MAPK signaling transduction, and thereby reducing the release of the proinflammatory cytokines.展开更多
Descending nociceptive modulation from the supraspinal structures plays an important role in cancer-induced bone pain (CIBP). Rostral ventromedial medulla (RVM) is a critical component of descending nociceptive facili...Descending nociceptive modulation from the supraspinal structures plays an important role in cancer-induced bone pain (CIBP). Rostral ventromedial medulla (RVM) is a critical component of descending nociceptive facilitation circuitry, but so far the mechanisms are poorly known. In this study, we investigated the role of RVM glial activation in the descending nociceptive facilitation circuitry in a CIBP rat model. CIBP rats showed significant activation of microglia and astrocytes, and also up-regulation of phosphorylated p38 mitogen-activated protein kinase (p38 MAPK) and pro-inflammatory mediators released by glial cells (IL-1β, IL-6, TNF-α and brain-derived neurotrophic factor) in the RVM. Stereotaxic microinjection of the glial inhibitors (minocycline and fluorocitrate) into CIBP rats’ RVM could reverse the glial activation and significantly attenuate mechanical allodynia in a time-dependent manner. RVM microinjection of p38 MAPK inhibitor (SB203580) abolished the activation of microglia, reversed the associated up-regulation of proinflammatory mediators and significantly attenuated mechanical allodynia. Taken together, these results suggest that RVM glial activation is involved in the pathogenesis of CIBP. RVM microglial p38 MAPK signaling pathway is activated and leads to the release of downstream pro-inflammatory mediators, which contribute to the descending facilitation of CIBP.展开更多
Olfactory bulb tissue transplantation inhibits P2X2/3 receptor-mediated neuropathic pain. However, the olfactory bulb has a complex cellular composition, and the mechanism underlying the action of purified transplante...Olfactory bulb tissue transplantation inhibits P2X2/3 receptor-mediated neuropathic pain. However, the olfactory bulb has a complex cellular composition, and the mechanism underlying the action of purified transplanted olfactory ensheathing cells(OECs) remains unclear. In the present study, we microencapsulated OECs in alginic acid, and transplanted free and microencapsulated OECs into the region surrounding the injured sciatic nerve in rat models of chronic constriction injury. We assessed mechanical nociception in the rat models 7 and 14 days after surgery by measuring paw withdrawal threshold, and examined P2X2/3 receptor expression in L4–5 dorsal root ganglia using immunohistochemistry. Rats that received free and microencapsulated OEC transplants showed greater withdrawal thresholds than untreated model rats, and weaker P2X2/3 receptor immunoreactivity in dorsal root ganglia. At 14 days, paw withdrawal threshold was much higher in the microencapsulated OEC-treated animals. Our results confirm that microencapsulated OEC transplantation suppresses P2X2/3 receptor expression in L4–5 dorsal root ganglia in rat models of neuropathic pain and reduces allodynia, and also suggest that transplantation of microencapsulated OECs is more effective than transplantation of free OECs for the treatment of neuropathic pain.展开更多
The cytochrome P450 proteins(CYP450s)have been implicated in catalyzing numerous important biological reactions and contribute to a variety of diseases.CYP26A1,a member of the CYP450 family,carries out the oxidative m...The cytochrome P450 proteins(CYP450s)have been implicated in catalyzing numerous important biological reactions and contribute to a variety of diseases.CYP26A1,a member of the CYP450 family,carries out the oxidative metabolism of retinoic acid(RA),the active metabolite of vitamin A.Here we report that CYP26A1 was dramatically upregulated in the spinal cord after spinal nerve ligation(SNL).CYP26A1 was mainly expressed in spinal neurons and astrocytes.HPLC analysis displayed that the content of all-trans-RA(at-RA),the substrate of CYP26A1,was reduced in the spinal cord on day 7 after SNL.Inhibition of CYP26A1 by siRNA or inhibition of CYP26A1-mediated at-RA catabolism by talarozole relieved the SNL-induced mechanical allodynia during the maintenance phase of neuropathic pain.Talarozole also reduced SNL-induced glial activation and proinflammatory cytokine production but increased anti-inflammatory cytokine(IL-10)production.The RA receptors RARα,RXRβ,and RXRγwere expressed in spinal neurons and glial cells.The promoter of Il-10 has several binding sites for RA receptors,and at-RA directly increased Il-10 mRNA expression in vitro.Finally,intrathecal IL-10 attenuated SNL-induced neuropathic pain and reduced the activation of astrocytes and microglia.Collectively,the inhibition of CYP26A1-mediated at-RA catabolism alleviates SNL-induced neuropathic pain by promoting the expression of IL-10 and suppressing glial activation.CYP26A1 may be a potential therapeutic target for the treatment of neuropathic pain.展开更多
目的:观察JNK/MCP-1通路在姜黄素抗大鼠糖尿病神经病理性疼痛(DNP)中的作用及机制。方法:雄性SD大鼠诱导为2型糖尿病神经病理性痛大鼠(DNP)模型,将其随机分为6组(n=27):DNP组、姜黄素组(Cur组)、溶剂对照组(DSC组)、JNK抑...目的:观察JNK/MCP-1通路在姜黄素抗大鼠糖尿病神经病理性疼痛(DNP)中的作用及机制。方法:雄性SD大鼠诱导为2型糖尿病神经病理性痛大鼠(DNP)模型,将其随机分为6组(n=27):DNP组、姜黄素组(Cur组)、溶剂对照组(DSC组)、JNK抑制剂组(DJ组)、JNK抑制剂溶剂对照组(DJS组)、姜黄素+单核细胞趋化蛋白1(MCP-1)激动剂组(DM组)。另取27只正常大鼠为正常对照组(C组),给药后3 d、7 d、14 d时测定机械缩足痛阈和热缩足潜伏期,并在同一时点取脊髓腰膨大及L4-6背根神经节(DRG),用免疫印迹法测定脊髓和DRG中p-JNK水平,用ELISA测定脊髓和DRG中的MCP-1含量。结果:与DNP组相比,在给药后的7 d、14 d Cur组、DJ组、DM组p-JNK的表达明显下降(P〈0.05);与C组相比,链脲佐菌素给药后其它6组MCP-1含量出现明显下降;与DNP组相比,在给药后的7 d、14 d Cur组、DJ组MCP-1出现明显上升,而DM组出现进一步下降(P〈0.05)。结论:DNP大鼠脊髓和DRG中的p-JNK、MCP-1表达明显升高,姜黄素减轻2型糖尿病大鼠神经病理性疼痛的机制可能与JNK/MCP-1信号通路有关。展开更多
基金Supported by Natural Science Foundation of Shanghai,China(No. 08ZR1405000)
文摘Objective:To investigate whether the activation of p38MAPK is involved in the neuropathic pain induced by P2X4 receptor,and the effects of activated P2X4 receptor and p38MAPK on expression of brain-derived neurotrophic factor (BDNF) in the chronic neuropathic pain.Methods:Lumbar intrathecal catheters were chronically implanted in male Sprague-Dawley rats.The right sciatic nerve was loosely ligated proximal to the sciatica's trifurcation at approximately 1.0 mm intervals with 4-0 silk sutures.The microglia inhibitor minocycline,P2X4 antagonist (TNP-ATP) and p38MAPK inhibitor (SB203580) were intrathecally administered every 12 h,3 d post-chronic constriction injury (CCI).Mechanical nociceptive thresholds were assessed with the paw withdrawal threshold (PWT) to von Frey filaments.The expression of P2X4 and BDNF were assessed by both immunohistochemical analysis and RT-PCR.Results:Intrathecal injection of minocycline or TNP-ATP or SB203580 significantly attenuated CCI-induced mechanical allodynia.The time courses of P2X4 receptor and BDNF expression were increased at all points after CCI and reached a peak level on postoperative d 7.Intrathecal injection of minocycline or TNP-ATP or SB203580 markedly suppressed the increase of CCI-induced P2X4 receptor and BDNF expression in the spinal cord.Conclusion:The activation of P2X4 receptor BDNF pathways contributes to neuropathic pain in CCI rats,and the activation of p38MAPK is involved in the neuropathic pain induced by P2X4 receptor.
文摘Applying a stimulating current to acupoints through acupuncture needles–known as electroacupuncture–has the potential to produce analgesic effects in human subjects and experimental animals. When acupuncture was applied in a rat model, adenosine 5-triphosphate disodium in the extracellular space was broken down into adenosine, which in turn inhibited pain transmission by means of an adenosine A1 receptor-dependent process. Direct injection of an adenosine A1 receptor agonist enhanced the analgesic effect of acupuncture. The analgesic effect of acupuncture appears to be mediated by activation of A1 receptors located on ascending nerves. In neuropathic pain, there is upregulation of P2X purinoceptor 3 (P2X3) receptor expression in dorsal root ganglion neurons. Conversely, the onset of mechanical hyperalgesia was diminished and established hyperalgesia was significantly reversed when P2X3 receptor expression was downregulated. The pathways upon which electroacupuncture appear to act are interwoven with pain pathways, and electroacupuncture stimuli converge with impulses originating from painful areas. Electroacupuncture may act via purinergic A1 and P2X3 receptors simultaneously to induce an analgesic effect on neuropathic pain.
基金supported by the National Natural Science Foundation of China,No.81760418 and 81260190the Natural Science Foundation of Jiangxi Province,No.20132BAB205023,20151BAB205022+1 种基金a grant from Science and Technology Research Project of Jiangxi Education Department,No.GJJ13159a grant from the Science and Technology Program of Department of Health of Jiangxi Province,No.20173010
文摘Schwann cell transplantation is a promising method to promote neural repair, and can be used for peripheral nerve protection and myelination. Microcapsule technology largely mitigates immune rejection of transplanted cells. We previously showed that microencapsulated olfactory ensheathing cells can reduce neuropathic pain and we hypothesized that microencapsulated Schwann cells can also inhibit neuropathic pain. Rat Schwann cells were cultured by subculture and then microencapsulated and were tested using a rat chronic constriction injury(CCI) neuropathic pain model. CCI rats were treated with Schwann cells or microencapsulated Schwann cells and were compared with sham and CCI groups. Mechanical withdrawal threshold and thermal withdrawal latency were assessed preoperatively and at 1, 3, 5, 7, 9, 11 and 14 days postoperatively. The expression of P2X3 receptors in L4-5 dorsal root ganglia of the different groups was detected by double-label immunofluorescence on day 14 after surgery. Compared with the chronic constriction injury group, mechanical withdrawal threshold and thermal withdrawal latency were higher, but the expression of P2X3 receptors was remarkably decreased in rats treated with Schwann cells and microencapsulated Schwann cells, especially in the rats transplanted with microencapsulated Schwann cells. The above data show that microencapsulated Schwann cell transplantation inhibits P2X3 receptor expression in L4-5 dorsal root ganglia and neuropathic pain.
文摘Objective: When nerve injury or inflammatory injury, different miRNA-mediated signal pathways are activated or inactivated, causing pain or hyperalgesia. Therefore, miRNA has become a new direction of pain mechanism research. We aimed to investigate the effect and mechanism of miR-362-3p on neuropathic pain in rats with chronic sciatic nerve injury (CCI). Methods: Neuropathic pain CCI rat model was established. Real-time-quantitative polymerase chain reaction (RT-PCR), Western blot, immunofluorescence, intrathecal injection, Enzyme-linked immunosorbent assay (ELISA), and dual luciferase reporter gene assays were used to explore the role of miR-362-3p in neuropathic pain development and the relationship between miR-362-3p and JMJD1A (Jumonji domain-containing 1A). Results: In the CCI group, the miR-362-3p level was increased and JMJD1A level was reduced in spinal cords and isolated microglia. The paw withdrawal threshold (PWT) and paw withdrawal latency (PWL) values were increased, the secretion of inflammatory factors was reduced, and the microglial marker Iba1 expression was decreased after intrathecal administration of miR-362-3p. miR-362-3p was observed to target JMJD1A. JMJD1A elevation abolished the inhibitory effects of miR-362-3p on neuropathic pain development. Conclusion: Intrathecal administration of miR-362-3p significantly relieved neuropathic pain in CCI rats and inhibited neuroinflammation possibly through regulating JMJD1A.
基金a grant from the National Nature Sciences Foundation of China (No. 30672426).
文摘Objective: To observe the effects of p38 mitogen activated protein kinase (MAPK) inhibitor SB203580 by intrathecal injection on the pain behavior and the spinal proinflammatory cytokines in a rat model of bone cancer pain induced by breast cancer cells. Methods: Eleven rats were used to establish the models of bone cancer pain, six rats were treated by intrathecal SB203580 injection, and the other 5 were as the controls. The paw withdrawal latency (PWL), histology and the spinal levels of IL-1β and TNF-α were detected. Results: All the 11 rats presented evident bone destruction and thermal hyperalgesia after intra-tibial injection of breast cancer cells. No effect of SB203580 on the bone destruction was observed. However, following intrathecal injection of SB203580, the left PWLs (12.12± 1.26 s at 16 days and 12.99 ± 1.65 s at 19 days) were significant higher than that of controls (9.05 ± 1.08 s at 16 days and 8.55 ± 1.60 s at 19 days), P 〈 0.05. Meanwhile, inkathecal injection of SB203580 evidently reduced the levels of spinal IL-1β and TNF-α. Conclusion: Intrathecal injection of SB203580 in a rat model of bone cancer pain cannot prevent the tibial destruction but significantly depress the thermalgia sensitivity, which might result from inhibiting inkacellular p38 MAPK signaling transduction, and thereby reducing the release of the proinflammatory cytokines.
基金supported by grants from the National Natural Science Foundation of China(No.30901396,No.81070890,No.30872441and No.81171259)
文摘Descending nociceptive modulation from the supraspinal structures plays an important role in cancer-induced bone pain (CIBP). Rostral ventromedial medulla (RVM) is a critical component of descending nociceptive facilitation circuitry, but so far the mechanisms are poorly known. In this study, we investigated the role of RVM glial activation in the descending nociceptive facilitation circuitry in a CIBP rat model. CIBP rats showed significant activation of microglia and astrocytes, and also up-regulation of phosphorylated p38 mitogen-activated protein kinase (p38 MAPK) and pro-inflammatory mediators released by glial cells (IL-1β, IL-6, TNF-α and brain-derived neurotrophic factor) in the RVM. Stereotaxic microinjection of the glial inhibitors (minocycline and fluorocitrate) into CIBP rats’ RVM could reverse the glial activation and significantly attenuate mechanical allodynia in a time-dependent manner. RVM microinjection of p38 MAPK inhibitor (SB203580) abolished the activation of microglia, reversed the associated up-regulation of proinflammatory mediators and significantly attenuated mechanical allodynia. Taken together, these results suggest that RVM glial activation is involved in the pathogenesis of CIBP. RVM microglial p38 MAPK signaling pathway is activated and leads to the release of downstream pro-inflammatory mediators, which contribute to the descending facilitation of CIBP.
基金supported by the National Natural Science Foundation of China,No.81260190the Natural Science Foundation of Jiangxi Province of China,No.20132BAB205023+1 种基金a grant from the Science and Technology Research Program of Department of Education of Jiangxi Province in China,No.GJJ13159a grant from the Science and Technology Program of Department of Health of Jiangxi Province,No.20132019
文摘Olfactory bulb tissue transplantation inhibits P2X2/3 receptor-mediated neuropathic pain. However, the olfactory bulb has a complex cellular composition, and the mechanism underlying the action of purified transplanted olfactory ensheathing cells(OECs) remains unclear. In the present study, we microencapsulated OECs in alginic acid, and transplanted free and microencapsulated OECs into the region surrounding the injured sciatic nerve in rat models of chronic constriction injury. We assessed mechanical nociception in the rat models 7 and 14 days after surgery by measuring paw withdrawal threshold, and examined P2X2/3 receptor expression in L4–5 dorsal root ganglia using immunohistochemistry. Rats that received free and microencapsulated OEC transplants showed greater withdrawal thresholds than untreated model rats, and weaker P2X2/3 receptor immunoreactivity in dorsal root ganglia. At 14 days, paw withdrawal threshold was much higher in the microencapsulated OEC-treated animals. Our results confirm that microencapsulated OEC transplantation suppresses P2X2/3 receptor expression in L4–5 dorsal root ganglia in rat models of neuropathic pain and reduces allodynia, and also suggest that transplantation of microencapsulated OECs is more effective than transplantation of free OECs for the treatment of neuropathic pain.
基金supported by STI2030-Major Projects(2022ZD0204700)the National Natural Science Foundation of China(32030048,31700899,and 32200817)+1 种基金the Graduate Student Scientific Research Innovation Projects of Jiangsu Province(KYCX18-2397)the Startup Foundation for Doctors of the Affiliated Hospital of Nantong University(Tdb1906).
文摘The cytochrome P450 proteins(CYP450s)have been implicated in catalyzing numerous important biological reactions and contribute to a variety of diseases.CYP26A1,a member of the CYP450 family,carries out the oxidative metabolism of retinoic acid(RA),the active metabolite of vitamin A.Here we report that CYP26A1 was dramatically upregulated in the spinal cord after spinal nerve ligation(SNL).CYP26A1 was mainly expressed in spinal neurons and astrocytes.HPLC analysis displayed that the content of all-trans-RA(at-RA),the substrate of CYP26A1,was reduced in the spinal cord on day 7 after SNL.Inhibition of CYP26A1 by siRNA or inhibition of CYP26A1-mediated at-RA catabolism by talarozole relieved the SNL-induced mechanical allodynia during the maintenance phase of neuropathic pain.Talarozole also reduced SNL-induced glial activation and proinflammatory cytokine production but increased anti-inflammatory cytokine(IL-10)production.The RA receptors RARα,RXRβ,and RXRγwere expressed in spinal neurons and glial cells.The promoter of Il-10 has several binding sites for RA receptors,and at-RA directly increased Il-10 mRNA expression in vitro.Finally,intrathecal IL-10 attenuated SNL-induced neuropathic pain and reduced the activation of astrocytes and microglia.Collectively,the inhibition of CYP26A1-mediated at-RA catabolism alleviates SNL-induced neuropathic pain by promoting the expression of IL-10 and suppressing glial activation.CYP26A1 may be a potential therapeutic target for the treatment of neuropathic pain.
文摘目的:观察JNK/MCP-1通路在姜黄素抗大鼠糖尿病神经病理性疼痛(DNP)中的作用及机制。方法:雄性SD大鼠诱导为2型糖尿病神经病理性痛大鼠(DNP)模型,将其随机分为6组(n=27):DNP组、姜黄素组(Cur组)、溶剂对照组(DSC组)、JNK抑制剂组(DJ组)、JNK抑制剂溶剂对照组(DJS组)、姜黄素+单核细胞趋化蛋白1(MCP-1)激动剂组(DM组)。另取27只正常大鼠为正常对照组(C组),给药后3 d、7 d、14 d时测定机械缩足痛阈和热缩足潜伏期,并在同一时点取脊髓腰膨大及L4-6背根神经节(DRG),用免疫印迹法测定脊髓和DRG中p-JNK水平,用ELISA测定脊髓和DRG中的MCP-1含量。结果:与DNP组相比,在给药后的7 d、14 d Cur组、DJ组、DM组p-JNK的表达明显下降(P〈0.05);与C组相比,链脲佐菌素给药后其它6组MCP-1含量出现明显下降;与DNP组相比,在给药后的7 d、14 d Cur组、DJ组MCP-1出现明显上升,而DM组出现进一步下降(P〈0.05)。结论:DNP大鼠脊髓和DRG中的p-JNK、MCP-1表达明显升高,姜黄素减轻2型糖尿病大鼠神经病理性疼痛的机制可能与JNK/MCP-1信号通路有关。