Introduction:Human chemerin is an adipokine that regulates chemotaxis,inflammation,and glucose metabolism.In addition,accumulating evidence suggests that chemerin promotes apoptosis,autophagy,and pyroptosis.However,th...Introduction:Human chemerin is an adipokine that regulates chemotaxis,inflammation,and glucose metabolism.In addition,accumulating evidence suggests that chemerin promotes apoptosis,autophagy,and pyroptosis.However,there are no data on its impact on eryptosis.The current study aimed to analyze the effects of human active Glu^(21)-Ser^(157) chemerin on eryptosis in vitro.Materials and Methods:Human chemerin 0-2-10-50μg/mL was incubated for 24 h with human erythrocytes(hematocrit 0.4%)obtained from eight healthy individuals.Flow cytometry-based determination of phospholipid scrambling,reactive oxygen species(ROS)production,and intracellular Ca^(2+)levels was performed.To supplement data on ROS and Ca^(2+)signaling in chemerin-mediated eryptosis,incubation in the presence or absence of antioxidants vitamin C and N-acetylcysteine and Ca^(2+)-binding agent EGTA was carried out,respectively.Confocal microscopy-based techniques were used to detect reactive nitrogen species(RNS)generation,involvement of caspase-3 and caspase-8,as well as the state of lipid order in cell membranes of erythrocytes exposed to human Glu^(21)-Ser^(157) chemerin.Results:Our observations suggest that human Glu^(21)-Ser^(157) chemerin had no impact on eryptosis parameters at 2μg/mL.However,chemerin stimulated phosphatidylserine externalization,ROS production,and Ca^(2+)accumulation at higher concentrations suggesting activation of eryptosis.Ca^(2+)uptake turned out to be at least partly required for chemerin-mediated eryptosis.Chemerin-mediated erythrotoxicity was additionally mediated by RNS,caspase-3,and caspase-8.Moreover,Glu^(21)-Ser^(157) chemerin promoted reduction in the liquid-ordered phase of cell membranes in erythrocytes.Conclusions:The present study first discloses that human chemerin can induce eryptosis via Ca^(2+)-dependent mechanisms at concentrations noticeably exceeding circulating levels.Thus,chemerin-induced eryptosis can hardly contribute to eryptosis-mediated anemia in diseases associated with enhanced levels of chemerin in blood.展开更多
Physical exe rcise effectively alleviates chronic pain associated with complex regional pain syndrome type-Ⅰ.However,the mechanism of exe rcise-induced analgesia has not been clarified.Recent studies have shown that ...Physical exe rcise effectively alleviates chronic pain associated with complex regional pain syndrome type-Ⅰ.However,the mechanism of exe rcise-induced analgesia has not been clarified.Recent studies have shown that the specialized pro-resolving lipid mediator resolvin E1 promotes relief of pathologic pain by binding to chemerin receptor 23 in the nervous system.However,whether the resolvin E1-chemerin receptor 23 axis is involved in exercise-induced analgesia in complex regional pain syndrome type-Ⅰ has not been demonstrated.In the present study,a mouse model of chronic post-ischemia pain was established to mimic complex regional pain syndrome type-Ⅰ and subjected to an intervention involving swimming at different intensities.Chronic pain was reduced only in mice that engaged in high-intensity swimming.The resolvin E1-chemerin receptor 23 axis was clearly downregulated in the spinal cord of mice with chronic pain,while high-intensity swimming restored expression of resolvin E1 and chemerin receptor 23.Finally,shRNA-mediated silencing of chemerin receptor 23in the spinal cord reve rsed the analgesic effect of high-intensity swimming exercise on chronic post-ischemic pain and the anti-inflammato ry pola rization of microglia in the dorsal horn of the spinal cord.These findings suggest that high-intensity swimming can decrease chronic pain via the endogenous resolvin E1-chemerin receptor 23 axis in the spinal cord.展开更多
文摘Introduction:Human chemerin is an adipokine that regulates chemotaxis,inflammation,and glucose metabolism.In addition,accumulating evidence suggests that chemerin promotes apoptosis,autophagy,and pyroptosis.However,there are no data on its impact on eryptosis.The current study aimed to analyze the effects of human active Glu^(21)-Ser^(157) chemerin on eryptosis in vitro.Materials and Methods:Human chemerin 0-2-10-50μg/mL was incubated for 24 h with human erythrocytes(hematocrit 0.4%)obtained from eight healthy individuals.Flow cytometry-based determination of phospholipid scrambling,reactive oxygen species(ROS)production,and intracellular Ca^(2+)levels was performed.To supplement data on ROS and Ca^(2+)signaling in chemerin-mediated eryptosis,incubation in the presence or absence of antioxidants vitamin C and N-acetylcysteine and Ca^(2+)-binding agent EGTA was carried out,respectively.Confocal microscopy-based techniques were used to detect reactive nitrogen species(RNS)generation,involvement of caspase-3 and caspase-8,as well as the state of lipid order in cell membranes of erythrocytes exposed to human Glu^(21)-Ser^(157) chemerin.Results:Our observations suggest that human Glu^(21)-Ser^(157) chemerin had no impact on eryptosis parameters at 2μg/mL.However,chemerin stimulated phosphatidylserine externalization,ROS production,and Ca^(2+)accumulation at higher concentrations suggesting activation of eryptosis.Ca^(2+)uptake turned out to be at least partly required for chemerin-mediated eryptosis.Chemerin-mediated erythrotoxicity was additionally mediated by RNS,caspase-3,and caspase-8.Moreover,Glu^(21)-Ser^(157) chemerin promoted reduction in the liquid-ordered phase of cell membranes in erythrocytes.Conclusions:The present study first discloses that human chemerin can induce eryptosis via Ca^(2+)-dependent mechanisms at concentrations noticeably exceeding circulating levels.Thus,chemerin-induced eryptosis can hardly contribute to eryptosis-mediated anemia in diseases associated with enhanced levels of chemerin in blood.
基金National Key R&D Program of China,Nos.2019YFA0110300 (to LZ),2021YFA1201400 (to LZ)Natural Science Foundation of Shanghai,No.21ZR1468600 (to LZ)Open Fund of the Key Laboratory of Cellular Physiology (Shanxi Medical University),Ministry of Education,No.KLMEC/SXMU-201910 (to XJ)。
文摘Physical exe rcise effectively alleviates chronic pain associated with complex regional pain syndrome type-Ⅰ.However,the mechanism of exe rcise-induced analgesia has not been clarified.Recent studies have shown that the specialized pro-resolving lipid mediator resolvin E1 promotes relief of pathologic pain by binding to chemerin receptor 23 in the nervous system.However,whether the resolvin E1-chemerin receptor 23 axis is involved in exercise-induced analgesia in complex regional pain syndrome type-Ⅰ has not been demonstrated.In the present study,a mouse model of chronic post-ischemia pain was established to mimic complex regional pain syndrome type-Ⅰ and subjected to an intervention involving swimming at different intensities.Chronic pain was reduced only in mice that engaged in high-intensity swimming.The resolvin E1-chemerin receptor 23 axis was clearly downregulated in the spinal cord of mice with chronic pain,while high-intensity swimming restored expression of resolvin E1 and chemerin receptor 23.Finally,shRNA-mediated silencing of chemerin receptor 23in the spinal cord reve rsed the analgesic effect of high-intensity swimming exercise on chronic post-ischemic pain and the anti-inflammato ry pola rization of microglia in the dorsal horn of the spinal cord.These findings suggest that high-intensity swimming can decrease chronic pain via the endogenous resolvin E1-chemerin receptor 23 axis in the spinal cord.