The prevalence of obesity is dramatic increased and strongly associated with cardiovascular disease. Adipokines, secreted from adipose tissues, are critical risk factors for the development of cardiomyopathy. Present study aimed to investigate the pathophysiological role of autotaxin in obesity-related cardiomyopathy. In high-fat diet-fed mice, autotaxin was mainly synthesized and secreted from adipocytes. The increased accumulation of cardiac autotaxin was positively associated with cardiac dysfunction in obese mice. Interestingly, specific blockage of adipose tissue autotaxin effectively protected against high-fat diet-induced cardiac structural disorders, left ventricular hypertrophy and dysfunction. Inhibition of autotaxin further improved high-fat diet-induced cardiac fibrosis and mitochondrial dysfunction, including improvement of mitochondrial structure, mass and activities. Our findings demonstrated intervention of adipose tissue biology could influence cardiac modification in obese mice, and adipocyte-derived autotaxin was a potential diagnostic marker and therapeutic target for obesity-related cardiomyopathy.
Yousheng Xu, Yongshun Wang, Jingjin Liu, Wei Cao, Lili Li, Hongwei Du, Enbo Zhan, Ruoxi Zhang, Huimin Liu, Maoen Xu, Tao Chen, Yilin Qu and Bo Yu
Jie Sun, Yan Liu, Jinhui Yu, Jin Wu, Wenting Gao, Liyuan Ran, Rujiao Jiang, Meihua Guo, Dongyu Han, Bo Liu, Ning Wang, Youwei Li, He Huang, Li Zeng, Ying Gao, Xin Li and Yingjie Wu
Astragalus polysaccharide (APS) is the main component of Astragalus membranaceus, an anti-diabetic herb being used for thousands of years in Traditional Chinese medicine (TCM). In this study, we aimed to evaluate the impact of APS on hepatic insulin signaling, autophagy and ER stress response in high-fat-diet (HFD)-induced insulin resistance (IR) mice. APS was intra-gastrically administrated and metformin was used as a control medicine. Apart from monitoring the changes in the important parameters of IR progression, the gene and protein expression of the key factors marking the state of hepatic ER stress and autophagic flux were examined. We found that, largely comparable to the metformin regime, APS treatment resulted in an overall improvement of IR, as indicated by better control of body weight and blood glucose/lipid levels, recovery of liver functions and regained insulin sensitivity. In particular, the excessive and pro-apoptotic ER stress response and inhibition of autophagy, as a result of prolonged HFD exposure, were significantly corrected by APS administration, indicating a switch of the cellular fate in favor of cell survival. Using the HepG2/IR cell model, we demonstrated that APS modulated the insulin-initiated phosphorylation cascades in a similar manner to metformin. This study provides a rationale for exploiting the insulin-sensitizing potential of APS, which has a therapeutic performance almost equivalent to metformin, to enrich our options in the treatment of IR.