Correlation between PPAR-α methylation level in peripheral blood and inflammatory factors of NAFLD patients with DM

The correlation between the methylation levels of peroxisome proliferator-activated receptor-α (PPAR-α) in the peripheral blood and the inflammatory factors associated with non-alcoholic fatty liver disease (NAFLD) patients with diabetes mellitus (DM) was investigated. Thirty-two samples of normal liver tissues (group N) and 35 samples of liver tissues from NAFLD patients with DM (group M) were used for the present study. The levels of alanine transaminase (ALT) and aspartate transaminase (AST) were measured using commercially available kits. The accumulation of lipid droplets and glycogen in the two groups was determined through Oil Red O staining and Sudan III staining. mRNA expression of tumor necrosis factor-α (TNF‑α), interleukin-lβ (IL-1β) and IL-6 in liver tissues of groups N and M were detected using reverse transcription-polymerase chain reaction (RT-PCR). In addition, western blotting was used to detect the protein expression of PPAR-α in liver tissues of both groups. The Statistical Product and Service Solutions (SPSS) 17.0 statistical software was used to analyze the expression difference of PPAR-α in liver tissues in the groups. The high levels of ALT and AST indicated severe liver injury in group M. Oil Red O staining and Sudan III staining showed a large number of lipid droplets and glycogen accumulation in the liver of group M patients. RT-PCR showed that the expression of inflammatory factors was extremely high and that the inflammatory injury was severe in the liver of group M patients. Western blotting showed that the expression of PPAR-α in group N was significantly higher than that in group M. ANOVA results showed that the expression of PPAR-α in liver tissues of groups N and M patients were statistically significantly different (P<0.01). Therefore, the abnormal expression of PPAR-α is closely associated with the occurrence and development of NAFLD complicated with DM, and that the abnormal expression of PPAR-α is closely related to inflammatory factors. Results from the present study suggest PPAR-α has important value in the study on NAFLD complicated with DM. The expression of PPAR-α can be used as a new basis for the diagnosis and treatment of NAFLD complicated with DM.