The Effect Of Inflammatory Stress On Hepatic Cholesterol Accumulation And Hepatic Fibrosis In C57BL/6J Mice

Part Ⅰ The inflammatory model of C57BL/6J mice in liverObjectives: To subcutaneous injection of10%casein in C57BL/6J miceinduce the chronic, low grade and systemic inflammatory model. Investigatewhether inflammatory stress exacerbates hepatic cholesterol accumulationand liver fibrosis.Methods:24male C57BL/6J mice with eight week-old were randomlyassigned to control group (N), casein group (NC), high cholesterol diet group(H), high cholesterol diet+casein group (HC), each group have six mice. Nand NC were be fed with a normal chow diet, H and HC were fed a highcholesterol diet containing15%fat and1.25%of cholesterol. NC and HCwere subcutaneous injection of0.5ml10%casein every other day, NS as acontrol in N and H for14weeks. Animals were sacrificed after14weeks andterminal blood samples and liver tissues were collected for ELISA andRT-PCR detection inflammatory factor.Results: Serum levels of IL-6and SAA significantly increased in thecasein-injected mice compared with their respective controls. PCR assay showed inflammation increased the mRNA expression of MCP-1andTNF-α, differences have statistical significance.Conclusion: After the subcutaneous injection casein for14weeks，itproduced the chronic, low grade and systemic inflammation model inC57BL/6J mice．This model had established successfully． Part Ⅱ the influence of inflammation to hepatic cholesterolaccumulation in mice.Objectives: Through C57BL/6J mice Inflammation model, study theinfluence of inflammation by text Serum and liver cholesterol liver andcholesterol metabolism related genes mRNA levels.Methods: To observe hepatic cholesterol accumulation by Oil Red Ostaining, assays total cholesterol (TC), low density protein (LDL) and highdensity protein (HDL) in serum.Total cholesterol and free cholesterol(FC)contents in liver were measured by enzyme methods. RT-PCR detection livercholesterol metabolism related genes mRNA levels.Results: Oil Red O staining showed inflammation aggravate lipidaccumulation in NC and HC mice compare with N and H,HC was mostobvious. Serum cholesterol testing results suggest, high cholesterol diet canincrease TC, LDL, HDL levels in serum, and inflammation can reduce it.Liver cholesterol testing results suggest, TC、FC、CE levels in liver were increase in NC、H、HC compare with N, and HC increased was most obvious(P<0.05).PCR assay showed inflammation increased the mRNAexpression of cholesterol metabolism related genes mRNA levels.Conclusion: Suggests that inflammation can affect cholesterol intake,and lead to abnormal accumulation of hepatic cholesterol. In the meantime,Due to the inflammation promotes the buildup of cholesterol from the bloodto the liver abnormalities in mice and the relative reduce cholesterol levels inthe blood. Part Ⅲ the influence of inflammation to endoplasmic reticulum stressand hepatic fibrosis in mice.Objectives: Through C57BL/6J mice Inflammation model, study theinfluence of inflammation to endoplasmic reticulum stress and hepaticfibrosis in mice.Methods: Through Sirius red staining and Masson staining observehepatic morphological changes and fibrosis degree. Through theimmunohistochemical text liver fibrosis related protein. Through RT-PCRdetection liver endoplasmic reticulum stress and hepatic fibrosis relatedgenes mRNA levels.Results: Sirius red and Masson staining showed that liver fibrosis wasmore extensive in NC,H, HC mice compare with N,HC was most obvious. PCR assay showed inflammation increased the mRNA expression ofpromote the liver fibrosis related genes mRNA levels and reduced themRNA expression of Anti fibrosis related gene.HC was most obvious. Theimmunohistochemical results showed fibrosis related protein expressioncompare with gene.Conclusion: Suggests that inflammation can lead to abnormalaccumulation of hepatic cholesterol and ERS had obvious correlation. Theinflammation can influence the mRNA expression of liver fibrosis relatedgenes to promote the development of liver fibrosis.