Dong Wan-Ru, Li Han, Li Yun-Feng, Wang Ning, Ma Bo-Yan, Lu Ge-Ling, Xin Xiang-Ru, Chen Bing-Bing
Drug Evaluation Center of Heilongjiang University of Chinese Medicine Harbin 150040, China.
Department of Epidemic Febrile Diseases, Heilongjiang University of Chinese Medicine Harbin 150040, China.
Zhongguo Zhong Yao Za Zhi. 2021 Sep;46(17):4480-4487. doi: 10.19540/j.cnki.cjcmm.20210621.401.
This study investigated the mechanism of improving impaired glucose tolerance(IGT) of rats by Huanglian Wendan Decoction from the perspective of the skeletal muscle Nod-like receptor protein 3(NLRP3)/cysteinyl aspartate specific proteinase-1(caspase-1)/interleukin-1β(IL-1β), interleukin-18(IL-18) pathway. Healthy male SD rats were fed with the diet containing 45% fat for 20 weeks, accompanied by a high-temperature and high-humidity environment and an inactive lifestyle, for the establishment of the IGT rat model. The rats were divided into the blank control group, model control group, metformin hydrochloride group(positive drug group, 0.05 g·kg(-1)·d(-1)) and Huanglian Wendan Decoction group(7.8 g·kg(-1)·d(-1)). After continuous intragastric administration for 4 weeks, the obesity and glycemic indexes of all the rats were measured. The fasting serum insulin(FINS) level was determined by ELISA, with the insulin sensitivity index(ISI) and insulin resistance index(IRI) calculated. The mRNA and protein expression le-vels of nuclear factor kappaB(NF-κB), NLRP3, caspase-1, IL-1β and IL-18 in skeletal muscle tissue were detected by real-time polymerase chain reaction(PCR), Western blot and immunofluorescence. Compared with the blank control group, the model control group witnessed significantly increased mRNA and protein expression of NF-κB, NLRP3, caspase-1, IL-1β and IL-18. As revealed by the comparison with the model control group, Huanglian Wendan Decoction could effectively regulate the obesity status, reduce body weight, correct the abnormal levels of 2-hour plasma glucose(2 hPG), insulin resistance index(IRI), insulin sensitivity index(ISI), and lower the mRNA and protein expression of NF-κB, NLRP3, caspase-1, IL-1β and IL-18 in the skeletal muscle tissue of IGT rats. Combined with previous studies, the above results showed that the occurrence and development of IGT was closely related to inflammatory response and the classic pyroptosis pathway in skeletal muscle, such as NLRP3/caspase-1/IL-1β, IL-18. It is inferred that the mechanism of Huanglian Wendan Decoction was to alleviate insulin resistance(IR) and then reverse the course of IGT lies in the regulation of the abnormal insulin receptor signaling pathway based on the NLRP3 inflammasome pathway.
本研究从骨骼肌Nod样受体蛋白3（NLRP3）/半胱天冬酶-1（caspase-1）/白细胞介素-1β（IL-1β）、白细胞介素-18（IL-18）通路角度探讨黄连温胆汤改善大鼠糖耐量受损（IGT）的机制。将健康雄性SD大鼠给予含45%脂肪的饲料喂养20周，并置于高温高湿环境且保持不活动的生活方式，以建立IGT大鼠模型。将大鼠分为空白对照组、模型对照组、盐酸二甲双胍组（阳性药物组，0.05 g·kg⁻¹·d⁻¹）和黄连温胆汤组（7.8 g·kg⁻¹·d⁻¹）。连续灌胃给药4周后，测定所有大鼠的肥胖及血糖指标。采用酶联免疫吸附测定法（ELISA）测定空腹血清胰岛素（FINS）水平，并计算胰岛素敏感性指数（ISI）和胰岛素抵抗指数（IRI）。通过实时聚合酶链反应（PCR）、蛋白质印迹法（Western blot）和免疫荧光法检测骨骼肌组织中核因子κB（NF-κB）、NLRP3、caspase-1、IL-1β和IL-18的mRNA和蛋白表达水平。与空白对照组比较，模型对照组NF-κB、NLRP3、caspase-1、IL-1β和IL-18的mRNA和蛋白表达显著升高。与模型对照组比较，黄连温胆汤可有效调节肥胖状态，降低体重，纠正餐后2小时血糖（2 hPG）、胰岛素抵抗指数（IRI）、胰岛素敏感性指数（ISI）的异常水平，并降低IGT大鼠骨骼肌组织中NF-κB、NLRP3、caspase-1、IL-1β和IL-18的mRNA和蛋白表达。结合既往研究，上述结果表明IGT的发生发展与骨骼肌的炎症反应及经典的细胞焦亡通路如NLRP3/caspase-1/IL-1β、IL-18密切相关。推测黄连温胆汤改善胰岛素抵抗（IR）进而逆转IGT进程的机制在于基于NLRP3炎性小体通路对异常胰岛素受体信号通路的调控。
