The present study aims to investigate the therapeutic effect and mechanism of glycyrrhizic acid(GA)in diabetic peripheral neuropathy(DPN).GA significantly mitigated nerve conduction velocity(NCV)deficit and morphologi...The present study aims to investigate the therapeutic effect and mechanism of glycyrrhizic acid(GA)in diabetic peripheral neuropathy(DPN).GA significantly mitigated nerve conduction velocity(NCV)deficit and morphological abnormality and reduced high-mobility group box-1(HMGB1)expression in the sciatic nerves of diabetic rats independent of blood glucose and body weight.Notably,GA alleviated the increase of HMGB1 and the decrease of cell viability in high glucose-stimulated RSC96 cells.Furthermore,GA obviously reduced the concentration of inflammatory cytokines in the sciatic nerves of diabetic rats and supernatants of high glucose-exposed RSC96 cells,then restored the decreased expression levels of nerve growth factor(NGF)and neuritin-1,and the increased expression levels of cleaved caspase-3 and neuron-specific enolase.Additionally,GA markedly inhibited receptor for advanced glycation end products(RAGE)expression,p38MAPK phosphorylation,and the nuclear translocation of NF-κBp65 in diabetic rats and high glucose-exposed RSC96 cells.The promotional effect of high glucose in RSC96 cells was diminished following Hmgb1 siRNA treatment.Our findings indicate that GA may exert neuroprotection on DPN by suppressing HMGB1,which lead to extenuation of inflammation response,balance of NGF,neuritin-1 and caspase-3,as well as inactivation of RAGE/p38MAPK/NF-κBp65 signaling pathway.展开更多
基金supported by the National Natural Science Foundation of China (Grant No. 81700723)Research Project of Jiangsu 333 Engineering (Grant No. BRA2016232)Research Project of Jiangsu Provincial Commission of Health and Family Planning (Grant No. F201549/H201667)
文摘The present study aims to investigate the therapeutic effect and mechanism of glycyrrhizic acid(GA)in diabetic peripheral neuropathy(DPN).GA significantly mitigated nerve conduction velocity(NCV)deficit and morphological abnormality and reduced high-mobility group box-1(HMGB1)expression in the sciatic nerves of diabetic rats independent of blood glucose and body weight.Notably,GA alleviated the increase of HMGB1 and the decrease of cell viability in high glucose-stimulated RSC96 cells.Furthermore,GA obviously reduced the concentration of inflammatory cytokines in the sciatic nerves of diabetic rats and supernatants of high glucose-exposed RSC96 cells,then restored the decreased expression levels of nerve growth factor(NGF)and neuritin-1,and the increased expression levels of cleaved caspase-3 and neuron-specific enolase.Additionally,GA markedly inhibited receptor for advanced glycation end products(RAGE)expression,p38MAPK phosphorylation,and the nuclear translocation of NF-κBp65 in diabetic rats and high glucose-exposed RSC96 cells.The promotional effect of high glucose in RSC96 cells was diminished following Hmgb1 siRNA treatment.Our findings indicate that GA may exert neuroprotection on DPN by suppressing HMGB1,which lead to extenuation of inflammation response,balance of NGF,neuritin-1 and caspase-3,as well as inactivation of RAGE/p38MAPK/NF-κBp65 signaling pathway.
