益智仁通过氧化三甲胺调节NF-κB通路减轻糖尿病肾脏疾病炎症反应

Mitigation of Inflammatory Reaction of Diabetic Kidney Disease by Yizhiren (益智仁) Regulating NF-κB Pathway through Trimethylamine Oxide

目的:探讨益智仁通过氧化三甲胺(TMAO)调节核转录因子-κB(NF-κB)信号通路减轻糖尿病肾脏疾病炎症反应的机制。方法:选择SPF级4周龄C57BKs雄性小鼠42只,其中12只正常小鼠随机分为正常对照组和氧化三甲胺0.2%组,30只造模小鼠给予高糖高脂饮食,造模成功后随机分为模型对照组、益智仁100、500 mg/kg组、卡格列净13 mg/kg组及氧化三甲胺抑制剂1%组。连续灌胃8周后,测定小鼠体质量、血糖、24 h尿量、24 h尿白蛋白(UA)、血肌酐(Scr)、血尿素氮(BUN)、尿蛋白/肌酐比值(ACR)、TMAO、肿瘤坏死因子-α(TNF-α)、白细胞介素-1β(IL-1β)、肾脏病理组织及磷酸化核转录因子-κB/核转录因子-κB(p-P65/P65)蛋白比值。结果:与正常对照组比较,模型对照组小鼠体质量、血糖、24 h尿量、24 h UA、血清Scr、BUN、ACR、TMAO、TNF-α、IL-1β含量、肾组织p-P65/P65蛋白比值及胶原沉积均显著升高(P<0.01),氧化三甲胺组p-P65/P65蛋白比值显著升高(P<0.05);与模型对照组比较,益智仁100、500 mg/kg组、卡格列净13 mg/kg组及氧化三甲胺抑制剂1%组24 h尿量、血清Scr、ACR、TAMO含量、肾组织胶原沉积及p-P65/P65蛋白比值均明显降低(P<0.05或P<0.01),益智仁500、100 mg/kg组及卡格列净13 mg/kg组24 h UA含量显著降低(P<0.01),益智仁500 mg/kg组、卡格列净13 mg/kg组及氧化三甲胺抑制剂1%组血清BUN、TNF-α含量明显降低(P<0.05或P<0.01),益智仁500 mg/kg组及氧化三甲胺抑制剂1%组IL-1β含量明显降低(P<0.05);相关性分析结果显示,TMAO水平与炎症因子TNF-α与IL-1β水平呈正相关(P<0.01)。结论:益智仁对DKD小鼠肾功能和炎症状态有明显的改善作用,其机制可能与降低TMAO水平,抑制NF-κB信号通路有关。

Objective:To explore the mechanism of Yizhiren(益智仁) regulating NF-κB signaling pathway through trimethylamine oxide(TMAO) to alleviate inflammatory reaction of diabetic kidney disease(DKD). Methods:A total of 42 SPF-grade 4-week-old C57BK male mice were selected, of which 12 normal mice were randomly divided into a normal control group and a 0.2% AMTO group, and 30 modeling mice were given a high-sugar and high-fat diet and were randomly divided into model control group, 500 mg/kg and 100mg/kg Yizhiren groups, 13 mg/kg canagliflozin group, and 1% TAMO inhibitor group. After oral administration for continuously eight weeks, the body weight, blood glucose, 24 h urine volume, 24 h urinary albumin(UA),serum creatinine(SCR),blood urea nitrogen(BUN), urinary protein/creatinine ratio(ACR),TMAO,tumor necrosis factor-α(TNF-α),IL-1β,renal pathological tissue, and phosphorylated nuclear transcription factor-κB/nuclear transcription factor-κB(P-P65/P65) protein ratio were measured. Results:Compared with the normal control group, the body weight, blood glucose, 24 h urine volume, the contents of 24 h UA,Scr, BUN,ACR,TMAO,TNF-α,and IL-1β,the ratio of P-P65/P65 protein, and collagen deposition of mice in the model control group were significantly increased(P<0.01). The ratio of P-P65/P65 protein in the 0.2% TMAO group was increased significantly(P<0.05). Compared with the model control group, 24 h urine volume, the contents of Scr, ACR,and TAMO,collagen deposition, and P-P65/P65 protein ratio in the 500 and 100 mg/kg Yizhiren groups, 13 mg/kg canagliflozin group, and 1% TAMO inhibitor group were significantly decreased(P<0.01 or P<0.05). The 24 h UA was significantly decreased in the 500 and 100 mg/kg Yizhiren groups and 13 mg/kg canagliflozin group(P<0.01). The contents of BUN and TNF-α in the 500 mg/kg Yizhiren group, 13 mg/kg canagliflozin group, and 1% TAMO inhibitor group were significantly decreased(P<0.01 or P<0.05). The levels of IL-1β in the 500 mg/kg Yizhiren group and 1% TAMO inhibitor group were significantly decreased(P<0.05). The correlation analysis showed that TMAO level was positively correlated with the levels of inflammatory cytokines TNF-α and IL-1β(P<0.01). Conclusion:Yizhiren can significantly improve renal function and inflammatory state in DKD mice, and the mechanism may be related to reducing TMAO levels and inhibiting the NF-κB signaling pathway.