Mechanisms Of Aldosterone Induced Autophagic Degradation Of Multivesicular Body In Liver Sinusoidal Endothelial Cell To Promote Hepatic Stellate Cell Activation And Liver Fibrosis

BackgroundLiver fibrosis is a common outcome of various chronic liver diseases and which progress to liver cirrhosis or even liver cancer,posing a serious threat to human health.The activation of hepatic stellate cell(HSC)is the core event of liver fibrosis,while activated HSC can secrete a large amount of extracellular matrix and cytokines,which eventually leads to the liver fibrosis.As the first line of defense in the liver against exogenous stimuli and play an immune function,LSECs also play an important role in the occurrence and development of liver fibrosis.In our previous works,we found that the levels of aldosterone and mineralocorticoid receptors were up regulated in the liver and circulation of both patients and related animal models of liver fibrosis.At the same time,we has confirmed in vitro and in vivo experiments that aldosterone can induce phenotypic changes in LSECs and may participate in the regulation of HSC activation through intercellular communication.Extracellular vesicles(EVs)can participate in intercellular communication and regulate various pathological and physiological processes such as proliferation and migration of downstream target cell.EVs have been shown to play an important role in the occurrence and development of various diseases.However,whether aldosterone regulates intercellular communication between LSECs and HSCs through EVs derived from LSECs during the process of liver fibrosis has not been reported.To further explore the effect of aldosterone on LSECs and HSCs during liver fibrosis,we investigated the mechanism by which aldosterone regulates EVs to participate in intercellular communication between LSECs and HSCs,thereby promoting HSC activation and liver fibrosis through multi-omics screening,in vitro and in vivo mechanism verification,and other methods.ObjectiveTo explore the mechanism by which aldosterone regulates EVs derived from LSECs to induce HSC activation and promote liver fibrosis.Methods1.Clinical detection:Collect liver tissue specimens and serum samples from patients with clinical liver fibrosis and detect the correlation between aldosterone levels and liver fibrosis lesions.2.In vivo experiments:Use aldosterone continuous pumping models and gene regulated rat models to investigate the role of aldosterone in liver fibrosis.3.In vitro experiments:Explore the phenotype and protein spectrum of LSEC after aldosterone stimulation.Co-culture EVs derived from LSECs with HSCs to observe the phenotype of HSCs and analyze related mechanisms.Results1.Upregulation of aldosterone levels in the serum of patients with liver fibrosis can be detected by Elisa,and 4-week continuous pumping of aldosterone leads to liver fibrosis in rats.2.Aldosterone affects the phenotype and protein expression of LSECs in vivo,and LSECs undergo deportation and activation of autophagic pathways.Decreased number of multivesicular bodies(MVBs)and increased fusion with lysosomes in LSECs were observed by Transmission electron microscopy,while EVs derived from LSECs were decreased in number and cargo.3.The EVs derived from LSECs could inhibit the activation of HSCs,while the EVs derived from aldosterone stimulated LSECs lost the ability.By analyzing the contents of the EVs of LSECs,we suggest that the miR-342-5P may play an antifibrotic role in the activation of HSCs.ConclusionAldosterone can induce HSC activation and liver fibrosis by promoting the autophagic degradation of multivesicular bodies of LSECs,resulting in the decrease in the total release of EVs from LSECs and in the content of anti-fibrotic miR-342-5P within the EVs,disrupting communication between LSECs and HSCs,which weakening the LSECs’ ability to maintain HSC quiescence.