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Background and Purpose: Non-alcoholic hepatic fatty liver disease (NAFLD) is a manifestation of the metabolic syndrome in the liver and non-alcoholic steatohepatitis (NASH) represents its advanced stage. R17 derived from bouchardatine, shows benefits in the metabolic syndrome, but has not been tested in the liver. The present study examined the pharmacological effects of R17 in a model of NAFLD/NASH and its mode of action.Experimental Approach: The effects of R17 were examined in mice fed a high-fat (HF) diet to induce the pathological characteristics of NAFLD/NASH and in cultures of HuH7 cells. We used histological and immunohistochemical techniques along with western blotting and siRNA. Generation of ROS and apoptosis were measured.Key Results: Administration of R17 (20 mg·kg-1 , i.p. every other day) for 5 weeks reversed HF-induced hepatic triglyceride content, inflammation (inflammatory cytokines and macrophage numbers), injury (hepatocyte ballooning and apoptosis, plasma levels of alanine aminotransferase and aspartate aminotransferase), and fibrogenesis (collagen deposition and mRNA expression of fibrosis markers). In cultured cells, R17 reduced cell steatosis from both lipogenesis and fatty acid influx. The attenuated inflammation and cell injury were associated with inhibition of both endoplasmic reticulum (ER) stress and oxidative stress. Notably, R17 activated the liver kinase B1-AMP-activated protein kinase (AMPK) pathway by inhibiting activity of ATP synthase, rather than direct stimulation of AMPK.Conclusion and Implications: R17 has therapeutic potential for NAFLD/NASH. Its mode of action involves the elimination of ER and oxidative stresses, possibly via activating the LKB1-AMPK axis by inhibiting the activity of ATP synthase. [ABSTRACT FROM AUTHOR]

Efferocytosis is defined as the clearance of apoptotic cells (ACs) in physiological and pathological states and is performed by efferocytes, such as macrophages. Efferocytosis can lead to the resolution of inflammation and restore tissue homoeostasis; however, the mechanisms of efferocytosis in determining inflammation resolution are still not completely understood, and the effects of efferocytosis on other proresolving properties need to be explored and explained. In this review, the process of efferocytosis will be summarized briefly, and then these mechanisms and effects will be thoroughly discussed. In addition, the association between mechanisms of efferocytosis in determining resolution of inflammation and cardiovascular diseases will also be reviewed, as an understanding of this association may provide information on novel treatment targets. [ABSTRACT FROM AUTHOR]

Background and Purpose: Non‐alcoholic steatohepatitis (NASH) is the more severe form of metabolic associated fatty liver disease (MAFLD) and no pharmacological treatment as yet been approved. Identification of novel therapeutic targets and their agents is critical to overcome the current inadequacy of drug treatment for NASH. Experimental Approach The correlation between heat shock factor 1 (HSF1) levels and the development of NASH and the target genes of HSF1 in hepatocyte were investigated by chromatin‐immunoprecipitation sequencing. The effects and mechanisms of SYSU‐3d in alleviating NASH were examined in relevant cell models and mouse models (the Ob/Ob mice, high‐fat and high‐cholesterol diet and the methionine‐choline deficient diet‐fed mice). The actions of SYSU‐3d in vivo were evaluated. Key Results: HSF1 is progressively reduced with mitochondrial dysfunction in NASH pathogenesis and activation of this transcription factor by its newly identified activator SYSU‐3d effectively inhibited all manifestations of NASH in mice. When activated, the phosphorylated HSF1 (Ser326) translocated to nucleus and bound to the promoter of PPARγ coactivator‐1α (PGC‐1α) to induce mitochondrial biogenesis. Thus, increasing mitochondrial adaptive oxidation and inhibiting oxidative stress. The deletion of HSF1 and PGC‐1α or recovery of HSF1 in HSF1‐deficiency cells showed the HSF1/PGC‐1α pathway was mainly responsible for the anti‐NASH effects of SYSU‐3d independent of AMP‐activated protein kinase (AMPK). Conclusion and Implications: Activation of HSF1 is a practical therapeutic approach for NASH treatment via the HSF1/PGC‐1α/mitochondrial pathway and SYSU‐3d can be considered as a potential candidate for the treatment of NASH. [ABSTRACT FROM AUTHOR]