摘要:
ETHNOPHARMACOLOGICAL RELEVANCE: Astragaloside IV (AST IV) is the active component of Astragalus membranaceus (Fisch.) Bunge, which regulates lipid and carbohydrate metabolism and improves insulin resistance. In this study, we investigated the effects of AST IV on insulin resistant cells and a non-alcoholic fatty liver disease (NAFLD) model induced by high-concentration insulin or oleic acid (OA) in HepG2 cells, as well as the associated regulatory markers. METHODS: First, the target of AST IV was predicted via pharmacophore model matching and molecular docking. Then, enzyme kinetics experiments were conducted in vitro to determine the effect of AST IV on the target protein. Next, AST IV's toxicity was tested on HepG2 cells in vitro, through an insulin resistance model and an NAFLD model, by high-concentration insulin or OA, respectively. To explore the effects of AST IV on insulin resistance and lipid metabolism, we detected the related indexes of glucose and lipid metabolism through commercially available kits. Relevant proteins were also detected by Western blot to provide future direction for study. RESULTS: Our preliminary results of pharmacophore model matching and molecular docking suggested that AST IV and protein tyrosine phosphatase 1B (PTP1B) can be well-combined through hydrogen bonding. Further, the enzyme kinetics experiment showed that AST IV was an effective and specific inhibitor to PTP1B. We found that the protein level of PTP1B in HepG2 cells was significantly increased after treating with high-concentration insulin or OA. Additionally, the intervention of AST IV significantly increased glucose consumption in an insulin resistance model and reduced the content of triglyceride (TG), total cholesterol (TC), and free fatty acid (FFA) in the NAFLD model. Moreover, the 2-N-(7-nitrobenze-2-oxa-1, 3 diazol-4-yl) (2-NBDG) uptake rate in the NAFLD model was also greatly improved. These results validated the effects of AST IV on improving insulin resistance and lipid accumulation. Furthermore, Western blot results illustrated that AST IV suppressed PTP1B and increased levels of phosphorylated insulin receptor (p-IR) and phosphorylated insulin receptor substrate-1 (p-IRS-1) in insulin-resistant HepG2 cells, while also decreasing protein levels of PTP1B and sterol element regulatory binding protein-1c (SREBP-1c) in the NAFLD model. CONCLUSION: This study demonstrated that AST IV inhibited PTP1B and effectively improved insulin resistance in insulin-resistant HepG2 cells and triglyceride accumulation in OA-treated HepG2 cells.
作者机构:
Medical School, Hunan University of Chinese Medicine, Changsha, China;[唐文静; 唐标; 刘余; 王乙钦] Medical School, Hunan University of Chinese Medicine, Changsha 410028, China
通讯机构:
[Biao Tang] M;Medical School, Hunan University of Chinese Medicine, Changsha, China
摘要:
Objective: To observe the effects of electroacupuncture (EA) on uterine prostaglandin F2α (PGF2α), cyclooxygenase 2 (COX-2) and nuclear factor κB (NF-κB) in rats with primary dysmenorrhea (PD) and to discuss the possible mechanism in EA intervening PD. Methods: Forty Sprague-Dawley female rats were randomly divided into a blank group, a model group, an EA group and an ibuprofen group, with 10 rats in each group. The PD model was established using estradiol benzoate combined with oxytocin in the model group, EA group and ibuprofen group. At the same time of modeling, rats in the EA group were given EA at Guanyuan (CV 4) and Sanyinjiao (SP 6) once a day for 20 min each time for 10 consecutive days. Ibuprofen was intragastrically administered once a day for 10 consecutive days in the ibuprofen group. The same amount of normal saline was intragastrically administered once a day for 10 consecutive days in the blank group and model group. The number of writhing of rats in each group within 30 min was compared on the 11th day just after the interventions. The uterine homogenate supernatant was separated and the PGF2α level was detected by enzyme-linked immunosorbent assay. Western blot was applied for the detection of the expression levels of COX-2, phospho-NF-κB p65 and NF-κB p65 proteins in uterine tissues. Results: Compared with the blank group, the number of writhing in the model group increased significantly (P<0.01), and the expression levels of PGF2α, COX-2, phospho-NF-κB p65 and NF-κB p65 proteins in uterine tissues were significantly increased (all P<0.01). Compared with the model group, the number of writhing in the EA group and ibuprofen group were significantly reduced (both P<0.01), and the expression levels of PGF2α and COX-2 protein in uterine tissues were significantly reduced (both P<0.01). Compared with the model group, the phospho-NF-κB p65 level in uterine tissues in the EA group was significantly reduced (P<0.01). Compared with the ibuprofen group, the phospho-NF-κB p65 level in the EA group was significantly reduced (P<0.01). Conclusion: The mechanism of EA for PD rats may be related to inhibiting the phosphorylation of NF-κB and reducing the levels of COX-2 and PGF2α in uterine tissues.
作者机构:
[李霞; 曹旺] College of Integrated Traditional Chinese and Western Medicine, Hunan University of Traditional Chinese Medicine, Changsha, 410028, China;[唐标] Medical School, Hunan University of Chinese Medicine, Changsha, 410028, China;[邓常清] College of Integrated Traditional Chinese and Western Medicine, Hunan University of Traditional Chinese Medicine, Changsha, 410028, China, Medical School, Hunan University of Chinese Medicine, Changsha, 410028, China
通讯机构:
[Deng, C.-Q.] C;College of Integrated Traditional Chinese and Western Medicine, China
摘要:
Primary dysmenorrhea (PD) constitutes a common gynecological disease among young women. The NLRP3 inflammasome may be activated and expressed in PD, but the mechanistic link between NLRP3 inflammasome activation and PD is still unclear. To investigate the potential role of NLRP3 inflammasome activation in the pathogenesis of PD, 30 female Kunming mice without pregnancy were used for experiments. The PD mouse model was constructed by 11 days of successive co-treatment with estradiol and oxytocin. MCC950, a potent and specific small-molecule inhibitor of the NLRP3 inflammasome, was used to treat PD mice. The disease level was assessed by the writhing response and hot water tail-flick test. The levels of prostaglandin E2 (PGE2) and prostaglandin F2 alpha (PGF2α) in the uterine tissues of mice were detected by ELISA. The expression levels of protein and cytokines, including NLRP3, cysteine aspartic acid-specific protease 1 (caspase-1), interleukin (IL)-1β, IL-18, nuclear factor kappa B (NF-κB) p65, phospho-NF-κB p65, and cyclooxygenase-2 (COX-2) were revealed by western blot analysis. MCC950 greatly ameliorated the writhing response induced by the combination of oxytocin and estradiol, with an increasing length of tail-flick latency. MCC950 also significantly decreased the levels of PGF2α and PGE2, and the expressions of NLRP3, caspase-1, IL-1β, IL-18, phospho-NF-κB p65, NF-κB p65, and COX-2 in the uterus. MCC950 markedly alleviated the pain and pathological damage in PD mice by inhibiting NLRP3 activation. The underlying mechanism may be related to hypoactive uterine inflammation via suppression of NLRP3 activation and the NF-κB/COX-2/PG pathway in uteruses of PD mice.