黄芪甲苷对慢性间歇性缺氧诱导的遗尿症大鼠TLR4-p38 MAPK通路的影响

Effect of astragaloside IV on TLR4-p38 MAPK Pathway in Rats with Chronic Intermittent Hypoxia Induced Enuresis

目的 探讨黄芪甲苷对慢性间歇性缺氧诱导的遗尿症大鼠Toll样受体4(Toll-like receptor-4,TLR4)/p38丝裂原活化蛋白激酶(p38 mitogen-activated protein kinase, p38 MAPK)信号通路的影响。方法 将SD大鼠随机分为对照组、模型组、黄芪甲苷低剂量组、黄芪甲苷中剂量组、黄芪甲苷高剂量组、去氨加压素组、脂多糖组、黄芪甲苷高剂量+脂多糖(Lipopolysaccharide, LPS)组,每组12只。除对照组外,其他组均需采用慢性间歇性缺氧诱导的方法构建遗尿症大鼠模型,各组大鼠每天于进入动物舱前1 h进行给药处理,1次/d,持续4周。末次处理24 h后,检测各组大鼠24 h排尿量及膀胱漏尿点压(bladder leak point pressures, BLPP)值的变化;ELISA法检测大鼠血清中抗利尿激素(antidiuretic hormone, ADH)含量;HE染色检测大鼠膀胱组织病理变化;比色法检测大鼠膀胱组织中超氧化物歧化酶(superoxide dismutase, SOD)活性、丙二醛(malonic dialdehyde, MDA)含量;Western blot检测大鼠膀胱组织中P2X3、TLR4、p-p38蛋白表达。结果 与对照组比较,模型组大鼠膀胱组织病理损伤严重,24 h排尿量增多,BLPP值变小,ADH含量、SOD活性降低,MDA含量和P2X3、TLR4、p-p38蛋白表达升高(P<0.05);与模型组比较,黄芪甲苷低剂量组、黄芪甲苷中剂量组、黄芪甲苷高剂量组、去氨加压素组大鼠膀胱组织病理损伤减轻,24 h排尿量减少,BLPP值变大,ADH含量、SOD活性升高,MDA含量和P2X3、TLR4、p-p38蛋白表达降低,LPS组大鼠膀胱组织病理损伤加剧,24 h排尿量增多,BLPP值变小,ADH含量、SOD活性降低,MDA含量和P2X3、TLR4、p-p38蛋白表达升高(P<0.05);与黄芪甲苷高剂量组比较,黄芪甲苷高剂量+LPS组大鼠膀胱组织病理损伤严重,24 h排尿量增多,BLPP值变小,ADH含量、SOD活性降低,MDA含量和P2X3、TLR4、p-p38蛋白表达升高(P<0.05)。结论 黄芪甲苷可能通过抑制TLR4/p38MAPK信号通路改善慢性间歇性缺氧诱导的大鼠遗尿症。

Objective To investigate the effect of astragaloside IV on Toll-like receptor 4(TLR4)/p38 mitogen-activated protein kinase(p38 MAPK)signal pathway in rats with chronic intermittent hypoxia induced enuresis.Methods SD rats were ran-domly grouped into control group,model group,astragaloside IV low,middle and high dose groups,desmopressin group,lipopo-lysaccharide(LPS)group and astragaloside IV high dose+LPS group,with 12 rats in each group.Except the control group,the enuresis rat model was constructed by chronic intermittent hypoxia induction.The rats in each group were administered 1 hour before entering the animal cabin,once a day for 4 weeks.After the last treatment for 24 hours,the changes of 24-hour urine out-put and bladder leakage point pressure(BLPP)of rats in each group were detected.The content of antidiuretic hormone(ADH)in rat serum was detected by ELISA.HE staining was applied to detect the pathological changes of bladder tissue.The activity of superoxide dismutase(SOD)and the content of malondialdehyde(MDA)in rat bladder tissue were detected with colorimetric method.Western blot was applied to detect the expressions of P2X3,TLR4 and p-p38 proteins in rat bladder tissue.Re-sults Compared with those of the control group,the pathological damage of the bladder tissue in the model group was serious,the 24 h urine output increased,the BLPP value decreased,the content of ADH and the activity of SOD decreased,the MDA content and the expressions of P2X3,TLR4 and p-p38 protein increased(P<0.05).Compared with those of the model group,the path-ological damage of bladder tissue of rats in the astragaloside IV low,middle and high dose groups and the desmopressin group re-duced,the 24 h urine output decreased,and the BLPP value increased,the ADH content and SOD activity increased,the MDA content and the expressions of P2X3,TLR4 and p-p38 protein decreased.In LPS group,the pathological injury of bladder tissue was aggravated,the urination volume was increased,the BLPP value was decreased,the ADH content and SOD activity were de-creased,and the MDA content and protein expressions of P2X3,TLR4 and P-P38 were increased(P<0.05).Compared with the astragaloside IV high dose group,the rats in astragaloside IV high dose+LPS group had serious pathological injury of bladder tissue,increased urination volume,decreased BLPP value,decreased ADH content and SOD activity and increased MDA content and protein expressions of P2X3,TLR4 and p-p38(P<0.05).Conclusion Astragaloside IV may improve enuresis induced by chronic intermittent hypoxia in rats by inhibiting TLR4/p38MAPK signal pathway.