Expression And Significance Of Oxidative Stress And Klotho Methylation In Non Alcoholic Fatty Liver Disease Patients Serum

Objective: In recent years,the incidence of Non-alcoholic fatty liver disease(NAFLD)continues to increase,but its pathogenesis is not clear.Oxidative stress damage is considered to play an important role in the "two hit" of NAFLD.Klotho is closely related to oxidative stress and metabolic diseases.Klotho promoter methylation regulates Klotho expression.To investigate the expression and significance of oxidative stress and Klotho methylation in Non alcoholic fatty liver disease(NAFLD)patients serum,It will provide a powerful theoretical and experimental basis for investigating the mechanism and intervention of Klotho in the pathogenesis of NAFLD.Methods: Serum were collected from 56 NAFLD patients in Southwest Medical University affiliated Hospital,50 normal people were selected as control group.General information included age,gender,height and bodyweight.High-density lipoprotein(HDL),low-density lipoprotein(LDL),total cholesterol(TC)and triglyceride(TG)were detected by automatic biochemical analyzer.The serum levels of Alanine aminotransferase(ALT),Aspartate aminotransferase(AST)and Glutamyl transpeptidase(GGT)were detected by automatic biochemical analyzer.The level of Superoxide Dismutase(SOD),Malondialdehyde(MDA)and Catalase(CAT)were determined with human enzyme-linked immunosorbent assay(ELISA)kit.The Klotho m RNA and protein expression were determined byReal-time Quantitative PCR Detecting System(q PCR)and Western-blot respectively.The Correlation analysis were determined by Pearson correlation analysis.The Klotho gene methylation status were determined by Methylation Specific PCR(MS-PCR)among groups.Software SPSS19.0 was used for statistical analysis.D’Agootino-Pearson was used to test the normality of the measurement data.The t-test was used for the normal distribution and the data was expressed as Mean±SD.The non-normal distribution uses the independent sample non-parametric test Mann-Whitney method and the data is Median ±IQR.The ratio or composition ratio is compared using chi-square test.Pearson correlation analysis was used for data correlation.P<0.05 indicates that the difference was statistically significant.Results: The body weight of the observation group was significantly higher than that of the control group(t=4.616,P<0.0001).The BMI index of the observation group was significantly higher than that of the control group(t=3.756,P=0.0003).The observation group TG was significantly higher than the control group(t=4.576,P<0.0001).The TC in the observation group was significantly higher than that in the control group(t=5.411,P<0.0001).The LDL in the observation group was significantly higher than that in the control group(t=9.787,P<0.0001).Compared with the control group,plasma SOD content(t=3.254,P=0.0015)and CAT(t=9.338,P<0.0001)in the observation group decreased significantly.ALT levels in the observation group were negatively correlated with plasma SOD(r=-0.3581,P=0.0067),but negatively correlated with CAT(r=-0.3317,P=0.0125).The Klotho m RNA in the plasma of two groups was significantly lower than that ofthe control group(t=19.13,P<0.0001)and protein expression(t=15.30,P<0.0001).Klotho protein expression in the observation group was positively correlated with plasma SOD level(r=0.3667,P=0.0054)and CAT level(r=0.2980,P=0.0257).The control group Klotho methylation rate was 24%;observation group methylation rate was 64%,the difference was statistically significant(x2=17.302,P<0.0001).Conclusion: Oxidative stress injury plays an important role in the "two hit" of NAFLD,Klotho methylation may be a clinical marker of plasma oxidative stress in NAFLD patients.