Mechanism Of MicroRNA-451 In Alcoholic Fatty Liver In C57 Mice

Background and purposeAlcoholic liver disease(ALD)is a global health problem.Long-term drinking can lead to fatty liver and inflammation,which can lead to liver fibrosis,cirrhosis,or liver cancer.Complement activation is involved in ethanol-induced liver damage,and C3-deficient mice are protected from ethanol-induced liver steatosis.C5 deficiency has protective effects on ethanol-induced inflammatory responses,but does not affect steatosis.Complement plays a role in alcoholic fatty liver disease(AFLD),but its mechanism is not fully understood.mi RNA is abundant in the liver and is involved in regulating various processes related to liver injury.At the same time,more and more evidence shows that mi RNAs play an important role in the development and pathogenesis of ALD,such as regulating inflammation and lipid metabolism.The purpose of this study was to investigate the role of mi R-451 in alcoholic fatty liver in mice and its mechanism of action,and to explore the regulatory effects of complement C3 activation.MethodThe mice’s alcoholic liver tissues were previously identified by high-throughput small RNA sequencing(GEO database: GSE126047)and identified as our research subject mi R-451.Subsequently,alcoholic fatty liver was constructed by using mi R-451 knockout and wild-type mice.Model and test related indicators such as: liver H & E staining,oil red O staining,serum liver function and biochemistry,serum inflammatory factors(TNF-α,IL-6)and C3 a,liver TG levels,and expression levels of key enzymes related to lipid metabolism,etc.The role of mi R-451 in alcoholic fatty liver in mice was analyzed.Cell experiments were used to analyze the effects of mi R-451 on lipid metabolism in vitro,and its target genes and its transcription factors were determined by luciferase reports.Then C3 knockout and wild-type mice were used to construct an alcoholic fatty liver model.CR2-Crry was also used to detect relevant indicators to analyze its regulatory effect on mi R-451.ResultIn the wild-type mouse model of alcoholic fatty liver,compared with the control group of mice,the experimental group of mice has the following performance: 1)liver H & E and oil red O staining shows significant fatty accumulation in liver tissue.2)serum ALT And AST increased significantly.3)liver triglyceride content increased significantly.By performing q RT-PCR on liver samples of mouse alcoholic fatty liver model,it was found that the expression of mi R-451 in the liver of the experimental group was significantly higher than that of the wild-type control group.Further,mi R-451 knockout mice were used to construct an alcoholic fatty liver model,which was divided into wild type control group,mi R-451 knockout control group,wild type experimental group and mi R-451 knockout experimental group.The following results were obtained: 1)Liver H & E and Oil Red O staining showed that the fat accumulation in liver tissue of mi R-451 knockout mice was significantly lower than that of wild-type mice.2)mi R-451 knockout mice Serum ALT and AST were significantly lower than those in the wild-type experimental group.3)For liver triglyceride content,mi R-451 knock-out experimental group mice decreased significantly,basically the same level as the control group.4)q RT-PCR results showed The mi R-451 knockout experimental group mice liver tissues decreased the m RNA levels of some key enzymes related to fat synthesis,such as ACC and FASN;while the m RNA levels of some key enzymes related to fatty acid degradation increased,such as CPT1 and ACSL1.Then,the same result was obtained using the alcohol model of the cell,and the following results were obtained: 1)The luciferase report confirmed that ACSL1 was the target gene of mi R-451.2)The luciferase report of the transcription factor binding site suggested that SREBF1 was mi R-451 transcription factor.In addition,liver H &E staining showed that: C3 knockout and CR2-Crry-treated mice in the experimental group had significantly reduced fat accumulation in liver tissue compared to wild-type and PBS-treated mice,and the expression of SREBF1 and mi R-451 also decreased.ConclusionMicro RNA-451 plays an important role in ethanol-induced liver steatosis in mice.The expression of mi R-451 in mouse alcohol liver tissue is significantly increased,which in turn reduces the expression of ACSL1.And fatty acid βoxidation decreases and fat synthesis increases leading to liver fat accumulation.SREBF1 may be a transcription factor that promotes the production of mature mi R-451.The increase of mi R-451 depends on the activation of SREBF1.Among them,the activation of complement C3 can in turn increase the expression of SREBF1.Complement C3 and mi R-451 are potential treatment targets for alcoholic fatty liver.