The Clinical Effect And Experimental Research Of SDF-1/CXCR4 In Chronic Liver Diseases

Stromal cell-derived factor-1(SDF-1)is a chemokine involved in the body's blood vessels generation,tissue injury and repair,it also can stimulate fibroblast proliferation and differentiation,promote extracellular matrix synthesis process.Chemokine receptors-4(CXCR4)is the SDF-1's receptor,SDF-1/CXCR4 axis is associated with many fibrosis diseases,such as pulmonary fibrosis,liver fibrosis,kidney and skin fibrosis.Studies have shown that when the body and organ damaged,the CXCR4+ stem cells homing to the damaged organs through SDF-1 concentration gradient,and differentiating to the parenchymal cells to repair the damaged organs.To further investigate the SDF-1/CXCR4 role in the progression of chronic liver diseases,this study is divided into two parts,the first part is to explore the SDF-1/CXCR4 clinical value in patients with chronic hepatitis B fibrosis,the second part is to investigate SDF-1 promoting bone marrow mesenchymal stem cells differentiating into hepatocytes in vitro.Part I The Clinical ResearchObjective To study the effect and expression of SDF-1/CXCR4 in the fibrosis of chronic hepatitis B.Methods118 patients of Department of Infectious Disease in the First Affiliated Hospital of Dalian Medical University were selected,their gender,age,liver stiffness measurement(LSM),HBV DNA quantification in serum(HBV DNA),stromal cell-derived factor-1(SDF-1),chemokine receptor-4(CXCR4),alanine aminotransferase(ALT),aspartate aminotransferase(AST),?-GGT(GGT),alkaline phosphatase(ALP),total bilirubin(TBIL),albumin(ALB),?-L-fucosidase(AFU)level were tested and analyzed. According to HBV DNA values,patients ??were divided into group HBV DNA <500IU/ml and group HBV DNA?500 IU/ml;according to LSM values,patients ??were divided into F0-1 period(<7.3KPA),F2 period(7.3-9.7KPA),F3 period(9.7-17.5KPA)and F4 period(>17.5KPA),the F0-1 was classified as non-liver fibrosis group,F2 and F3 as the liver fibrosis group,F4 as liver cirrhosis group.The expressions of SDF-1,CXCR4 and liver function were compared between group HBV DNA <500 IU/ml and group HBV DNA?500 IU/ml,among the non-liver fibrosis group,hepatic fibrosis group and cirrhosis group.Result1.The number of selected cases at different stages of fibrosis51 in the non-liver fibrosis group(43.22%),47 people in liver fibrosis group(39.83%),20 in liver cirrhosis group(16.95%)of 118 cases in total.2.The serum SDF-1,CXCR4 levels between different groups of HBV DNA Lg SDF-1 value in HBV DNA <500 IU/ml group was-0.20 ± 0.47 ng/ml,HBV DNA?500 IU/ml group was-0.37 ± 0.53 ng/ml,the difference between the two groups was not significant(P>0.05);Lg CXCR4 value in HBV DNA<500 IU/ml group was-0.38 ± 0.45 ng/ml,HBV DNA?500 IU/ml group was-0.50 ± 0.43 ng/ml.The levels of SDF-1 and CXCR4 in group HBV DNA<500 IU/ml were higher than that in group HBV DNA?500 IU/ml,the difference between the two groups was not statistically significant(P>0.05).3.The serum SDF-1,CXCR4 levels at different stages of fibrosis Lg SDF-1 in the non-liver fibrosis group was-0.43 ± 0.58 ng/ml,fibrosis group was-0.17 ± 0.39 ng/ml,cirrhosis group was-0.15 ± 0.48 ng/ml;Lg CXCR4 in the non-liver fibrosis group was-0.56 ± 0.53 ng/ml,fibrosis group was-0.37 ± 0.33 ng/ml,cirrhosis group was-0.29 ± 0.43 ng/ml.In terms of the expressions of serum SDF-1 and CXCR4,group liver cirrhosis and group liver fibrosis were significantly increased than the non-liver fibrosis group(P<0.05),there is no significant difference between the group of liver fibrosis and cirrhosis.4.Level of liver function in the different stages of liver fibrosis Levels of ALT,AST,GGT in hepatic fibrosis group was increased than non-liver fibrosis group(P<0.05)with fibrosis progressed gradually,and difference between any two of the three groups was significant(P<0.05),ALP,TBIL,AFU of cirrhosis group were significantly higher than non-liver fibrosis group,ALB of cirrhosis group was lower than non-liver fibrosis group(P<0.05).Conclusion1.The level of SDF-1 and CXCR4 in group HBV DNA <500 IU/ml were higher than that in group HBV DNA?500 IU/ml.2.Expressions of SDF-1,CXCR4 increase with the LSM stage,and have a certain significance for the early diagnosis and prediction of liver cirrhosis.3.Liver function impairment always occurs during the progression of liver fibrosis.Part II Basic ResearchObjective To investigate the effect and mechanism of SDF-1 on inducing bone marrow-derived mesenchymal stem cells'(BM-MSCs)hepatic differentiation.Methods Murine BM-MSCs were isolated with whole bone marrow adherence,then identified by immunocytochemical staining and flow cytometry.Passage 2 cells were divided into 4groups,and their differentiation was induced by cell factors added into medium for 28days: A group(negative control,NC): containing 15% Fetal Bovine Serum(FBS);group B(HGF group): Added 20 ng/ml hepatocyte growth factor(HGF);group C group(SDF-1 group): Added 50 ng/ml SDF-1;group D(HGF + SDF-1 group): Added 20ng/ml HGF + 50 ng/ml SDF-1.ALB was chosen as hepatocellular marker and cytokeratin-18(CK-18)as cholangiocellular marker.The protein and mRNA expression levels of ALB and CK-18 were used to determine the differentiation of BM-MSCs by immunocytochemical staining,western blot and Real-time PCR on day 7,14,21 and 28 during induction.Result The relative expressions of ALB and CK-18 resulted in time-dependent increases in the group supplemented with HGF and SDF-1 singly.Combination of HGF and SDF-1,the expressions of ALB and CK-18 were higher than that of alone(P<0.05).Conclusion This study suggested that SDF-1 had an effect on inducing BM-MSCs' hepatic differentiation and may play a synergistic role with HGF.