Alisol A 24-Acetate Prevents Hepatic Steatosis and Metabolic Disorders in HepG2 Cells

Background/Aims: Acetic acid (AcOH), a short-chain fatty acid, is reported to have some beneficial effects on metabolism. Therefore, the aim of this study was to investigate the regulatory mechanism of acetic acid on hepatic lipid metabolism in BRL-3A cells. Methods: We cultured and treated BRL-3A cells with different concentrations of sodium acetate (neutralized acetic acid) and BML-275 (an AMPKα inhibitor). The total lipid droplet area was measured by oil red O staining, and the triglyceride content was determined by a triglyceride detection kit. We detected mRNA and protein levels of lipid metabolism-related signalling molecules by RT-PCR and Western blot. Results: Acetic acid treatment increased AMPKα phosphorylation, which subsequently increased the expression and transcriptional activity of peroxisome proliferator-activated receptor α and upregulated the expression of lipid oxidation genes. These changes ultimate led to increasing levels of lipid oxidation in BRL-3A cells. Furthermore, elevated AMPKα phosphorylation reduced the expression and transcriptional activity of the sterol regulatory element-binding protein 1c, which reduced the expression of lipogenic genes, thereby decreasing lipid biosynthesis in BRL-3A cells. Consequently, triglyceride content in acetate-treated BRL-3A cells was significantly decreased. Conclusions: These results indicate that acetic acid activates the AMPKα signalling pathway, leading to increased lipid oxidation and decreased lipid synthesis in BRL-3A cells, thereby reducing liver fat accumulation in vitro.

Section: Discussionmentioning

confidence: 99%

Acetic Acid Influences BRL-3A Cell Lipid Metabolism via the AMPK Signalling Pathway

Xiao

et al. 2018

“…After 7 days of culturing, medium were replaced with high glucose (33mM) medium [29] or high glucose medium containing fenofibrate (1, 5 or 10 mM [30]) for 24h, or fenofibrate (5mM) together with glibenclamide (a NLRP3 inflammasome inhibitor; 5mM [31]) and LPS (Sigma-Aldrich, St. Louis, MO, 1µg/ml [32]) for 24h. Effects of fenofibrate on high glucose induced EPCs dysfunction were assessed by both the migration and tube formation capacities, and by intracellular NO and O 2 - levels.…”

Section: Methodsmentioning

confidence: 99%

PPARα Agonist Stimulated Angiogenesis by Improving Endothelial Precursor Cell Function Via a NLRP3 Inflammasome Pathway

Deng¹,

Han²,

Zheng³

et al. 2017

Background: Impaired wound healing is a common complication of diabetes and is the leading cause of lower extremity amputation. Treatment with fenofibrate, a peroxisome proliferators–activated receptor α (PPARα) agonist, was associated with a lower risk of amputations, particularly minor amputations without known large-vessel diseases, probably through non-lipid mechanisms. The current study aimed to test our hypothesis that fenofibrate stimulates angiogenesis and restores endothelial precursor cell (EPC) function via inhibiting Nod-like receptor protein 3 (NLRP3) inflammasome in streptozotocin (STZ)-induced diabetic mice. Methods: Male C57BL/6 mice were randomly divided into three groups: control, STZ-induced diabetic mice and fenofibrate treated diabetic group. Wound closure was assessed by wound area and CD31 positive capillaries. Both the migration and tube formation capacities of EPCs were measured. Intracellular nitric oxide (NO) and superoxide (O₂^-) levels were determined. Activity of NLRP3 inflammasome in EPCs was assessed by measuring thioredoxin-interacting protein (TXNIP), NLRP3, and caspase-1 expression. Results: Compared with the untreated diabetic mice, wound closure and capillary densities were significantly increased in fenofibrate treated group. Fenofibrate treatment restored EPC function, increased NO production, and decreased O₂^- level in EPCs of diabetic mice. Furthermore, fenofibrate deregulated the activity of NLRP3 inflammasome by reducing TXNIP, NLRP3 and caspase-1 expression in EPCs of diabetic mice. In vitro, fenofibrate prevented high glucose induced EPC dysfunction, deregulated NLRP3 inflammasome activity. In addition, fenofibrate inhibited IL-1β expression caused by combination use of high glucose and lipopolysaccharide. Conclusion: Fenofibrate can accelerate wound healing in diabetic mice, which at least in part was mediated by improving the impaired EPC function via a NLRP3 inflammasome pathway, suggesting the significance of PPARα agonists in the treatment of diabetes.

“…Scientists have paid close attention to remedy NAFLD. Zeng et al demonstrated that Alisol A 24-acetate effectively ameliorated hepatic steatosis and inhibited inflammation [6]. Another study also reported that taurine play protective role of in NAFLD via FGF-21/SIRT1 axis [7].…”

Section: Introductionmentioning

confidence: 98%

Genipin Reverses HFD-Induced Liver Damage and Inhibits UCP2-Mediated Pyroptosis in Mice

Zhong

Liu

et al. 2018

Background/Aims: Liver damage is a typical manifestation of nonalcoholic fatty liver disease (NAFLD). It originates from excessive fat accumulation, leading to hepatocyte death, inflammation, and fibrosis. Nonalcoholic steatohepatitis (NASH) is a type of NAFLD with a prevalence of 49% in morbidly obese patients. Pyroptosis plays an important role in the development of NASH; thus, it is important to elucidate the effect of lipid accumulation on pyroptosis. Genipin (GNP), a natural water-soluble cross-linking agent, has hepatoprotective effects and decreases lipid accumulation in the liver; however, the mechanisms underlying these effects are unknown. Methods: In this study, qPCR and Western blot were used to examine pyroptotic gene expression in high-fat diet (HFD) induced obese mice and free fatty acids (FFAs) treated hepatocytes. At the same time, relative lactate dehydrogenase (LDH) release and Hoechst & propidium iodide (PI) staining were done to verify cell death. To explore the molecular mechanism, cell transfection were constructed with siRNA or plasmid to obtain knockdown or overexpression hepatocytes. Results: We found that HFD-fed mice and FFAs-treated hepatocytes had obvious pyroptosis, and addition of GNP reversed liver damage and inhibited pyroptosis both in vitro and in vivo. Besides, UCP2 knockdown cells showed suppressed FFAs-mediated pyroptosis, as determined by decreased pyroptotic gene expression, reduced lactate dehydrogenase (LDH) release, and reduced cell death. Consistent with this, cells transfected with UCP2 had upregulated pyroptotic gene expression, increased LDH release, and increased cell death. Conclusion: GNP reverses HFD-induced liver damage and inhibits UCP2-mediated pyroptosis. Thus, GNP may serve as a potential therapeutic candidate for NAFLD.