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Liver fibrosis is characterized by the activation and transformation of hepatic stellate cells (HSCs) induced by various injury factors. The degree of liver fibrosis can be significantly improved, but persistent injury factors present a significant therapeutic challenge. Hepatocytes are the most important parenchymal cell type in the liver. In this study, we explored the molecular mechanisms by which damaged liver cells activate HSCs through extracellular vesicles. We established a coculture model of LO2 and LX2 and validated its exosomal transmission activity. Subsequently, differentially expressed long noncoding RNAs (lncRNAs) were screened through RNA sequencing and their mechanisms of action as competing endogenous RNAs (ceRNAs) further confirmed using biological methods, such as FISH and luciferase assays. Damaged liver cells induced activation of LX2 and upregulation of liver fibrosis‐related markers. Exosomes extracted and identified from the supernatant fraction contained differentially expressed lncRNA cytoskeleton regulator RNA (CYTOR) that competed with microRNA‐125 (miR‐125) for binding to glial cell line‐derived neurotrophic factor (GDNF) in HSCs, in turn, promoting LX2 activation. MiR‐125 could target and regulate both CYTOR and GDNF and vice versa, as verified using the luciferase assay. In an in vivo model, damaged liver extracellular vesicles induced the formation of liver fibrosis. Notably, downregulation of CYTOR within extracellular vesicles effectively inhibited liver fibrosis. The lncRNA CYTOR in exosomes of damaged liver cells is upregulated and modulates the expression of downstream GDNF through activity as a ceRNA, providing an effective mechanism for activation of HSCs. [ABSTRACT FROM AUTHOR]

Hepatocellular carcinoma (HCC) is one of the most common malignant diseases associated with a high rate of mortality. Frequent intrahepatic spread, extrahepatic metastasis, and tumor invasiveness are the main factors responsible for the poor prognosis of patients with HCC. Hypoxia‐inducible factor 1 (HIF‐1) has been verified to play a critical role in the metastasis of HCC. HIFs are also known to be modulated by small molecular metabolites, thus highlighting the need to understand the complexity of their cellular regulation in tumor metastasis. In this study, lower expression levels of oxoglutarate dehydrogenase‐like (OGDHL) were strongly correlated with aggressive clinicopathologic characteristics, such as metastasis and invasion in three independent cohorts featuring a total of 281 postoperative HCC patients. The aberrant expression of OGDHL reduced cell invasiveness and migration in vitro and HCC metastasis in vivo, whereas the silencing of OGDHL promoted these processes in HCC cells. The pro‐metastatic role of OGDHL downregulation is most likely attributed to its upregulation of HIF‐1α transactivation activity and the protein stabilization by promoting the accumulation of L‐2‐HG to prevent the activity of HIF‐1α prolyl hydroxylases, which subsequently causes an epithelial–mesenchymal transition process in HCC cells. These results demonstrate that OGDHL is a dominant factor that modulates the metastasis of HCC. [ABSTRACT FROM AUTHOR]

Background and Purpose: Non-alcoholic fatty liver disease (NAFLD) is considered to be one of the most common chronic liver diseases across worldwide. Astaxanthin (Ax) is a carotenoid, and beneficial effects of astaxanthin, including anti-oxidative, anti-inflammatory, and anti-tumour activity, have been identified. The present study aimed to elucidate the protective effect of astaxanthin against NAFLD and its underlying mechanism.Experimental Approach: Mice were fed either a high fat or chow diet, with or without astaxanthin, for up to 12 weeks. L02 cells were treated with free fatty acids combined with different doses of astaxanthin for 48 h. Histopathology, expression of lipid metabolism, inflammation, apoptosis, and fibrosis-related gene expression were assessed. And the function of mitochondria was also evaluated.Key Results: The results indicated that astaxanthin attenuated HFD- and FFA-induced lipid accumulation and its associated oxidative stress, cell apoptosis, inflammation, and fibrosis both in vivo and in vitro. Astaxanthin up-regulated FGF21 and PGC-1α expression in damaged hepatocytes, which suggested an unrecognized mechanism of astaxanthin on ameliorating NAFLD.Conclusion and Implications: Astaxanthin attenuated hepatocyte damage and mitochondrial dysfunction in NAFLD by up-regulating FGF21/PGC-1α pathway. Our results suggest that astaxanthin may become a promising drug to treat or relieve NAFLD. [ABSTRACT FROM AUTHOR]

Background and Aim: Liver fibrosis is a worldwide clinical challenge during the progression of chronic liver disease to liver cirrhosis. Shikonin is extracted from the root of Lithospermum erythrorhizon with antioxidant, anti‐inflammatory, anticancer, and wound‐healing properties. The study aims to investigate the protective effect of shikonin on liver fibrosis and its underlying mechanism. Methods: Two liver fibrosis models were established in male C57 mice by intraperitoneal injection of CCl4 or bile duct ligation. Shikonin was administered orally three times weekly at a dose of 2.5 or 5 mg/kg. Protein and mRNA expressions were assayed by quantitative real‐time polymerase chain reaction, Western blotting, and immunohistochemical staining. Results: Shikonin significantly inhibited activation of hepatic stellate cells and extracellular matrix formation by downregulating the transforming growth factor‐β1 expression and maintaining the normal balance between metalloproteinase‐2 and tissue inhibitor of metalloproteinase‐1. Shikonin also decreased hepatic stellate cell energy production by inhibiting autophagy. Conclusions: The results confirmed that shikonin attenuated liver fibrosis by downregulating the transforming growth factor‐β1/Smads pathway and inhibiting autophagy. [ABSTRACT FROM AUTHOR]

Hepatocellular carcinoma (HCC) is one of the few cancers with a continuous increase in incidence and mortality. Drug resistance is a major problem in the treatment of HCC. In this study, two sorafenib-resistant HCC cell lines and a nude mouse subcutaneously tumor model were used to explore the possible mechanisms leading to sorafenib resistance, and to investigate whether aspirin could increase the sensitivity of hepatoma cells to sorafenib. The combination of aspirin and sorafenib resulted in a synergistic antitumor effect against liver tumors both in vitro and in vivo. High glycolysis and PFKFB3 overexpression occupied a dominant position in sorafenib resistance, and can be targeted and overcome by aspirin. Aspirin plus sorafenib induced apoptosis in tumors without inducing weight loss, hepatotoxicity or inflammation. Our results suggest that aspirin overcomes sorafenib resistance and their combination may be an effective treatment approach for HCC. [ABSTRACT FROM AUTHOR]