[Association between polymorphisms in pigment epithelium-derived factor gene promoter region and non-alcoholic fatty liver disease in type 2 diabetes mellitus].

OBJECTIVE: To investigate the association of serum pigment epithelium-derived factor (PEDF) level and polymorphisms in PEDF gene promoter region -358G→A with non-alcoholic fatty liver disease (NAFLD) in patients with type 2 diabetes mellitus (T2DM) of Han Nationality in Fujian Province. METHODS: A total of 282 T2DM patients with NAFLD (DM1 group) and 170 age- and gender-matched T2DM patients without NAFLD (DM2 group) were examined for PEDF gene SNP-358G→A polymorphisms using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Serum pigment epithelium-derived factor(PEDF) level, fasting plasma glucose (FPG), fasting insulin (FINS) and glycosylated hemoglobin (HbA1c) were also measured. RESULTS: The patients in DM1 group showed a significantly higher mean level of serum PEDF than those in DM2 group (P<0.05). Logistic regression analysis revealed that PEDF level was an independent risk factor for NAFLD in T2DM. The frequencies of PEDF gene -358G→A genotypes (GG, GA, and AA) and alleles (G/A) differed significanly between DM1 and DM2 groups (P<0.05). In terms of PEDF gene SNP -358G→A alleles, the GA genotype carriers had a 2.032 times higher risk of developing NAFLD compared with the GG genotype carriers, and the risk increased to 2.068 times in the carriers of the A allele (GA and AA genotypes; P<0.05). CONCLUSION: Serum PEDF level is an independent risk factor of NAFLD in T2DM. Elevated serum PEDF level is a protective factor against insulin resistance. In T2DM patients, PEDF gene promoter region -358G→A polymorphism is associated with NAFLD, and the A allele contributes to an increased risk of NAFLD.