title: [Association between leptin gene promoter methylation and type 2 diabetes mellitus].
abstract: OBJECTIVE
  To assess the association between leptin gene promoter methylation and serum leptin concentrations in patients with impaired glucose regulation (IGR) and type 2 diabetes mellitus (T2DM).
  
  
  METHODS
  Methylation status of leptin gene promoter was determined with methylation-specific polymerase chain reaction. Serum leptin concentrations were determined using enzyme-linked immunosorbent assay.
  
  
  RESULTS
  Among three groups of individuals with different levels of glucose, the methylation rates of leptin gene in IGR and T2DM groups were 43.6 % and 31.5 %, respectively, which were significantly lower than that of healthy subjects (59.2%; Chi-square=22.499 and 5.109, respectively, P<0.05). A lower methylation rate was also observed in T2DM group compared with IGR group (Chi-square=3.962, P<0.05). Leptin levels in both T2DM and IGR groups were elevated compared with normoglycemic subjects, but only T2DM group was significantly higher (q=6.81, P<0.01). Linear regression analysis indicated that serum leptin concentrations has increased along with declining of DNA methylation rate (r=-0.95, P<0.01).
  
  
  CONCLUSIONS
  Lower levels of leptin gene promoter DNA methylation and serum leptin concentrations are associated with the development of diabetes. Measurement of the methylation status of leptin gene promoter and expression can facilitate early intervention of the disease.
authors.affiliation: Department of Endocrinology,Zhongnan Hospital, Wuhan University, Wuhan, Hubei, People's Republic of China.
authors.forename: Mei
authors.initials: M
authors.lastname: Yang
authors.forename: Jia-zhong
authors.initials: JZ
authors.lastname: Sun
authors.forename: Yan-lei
authors.initials: YL
authors.lastname: Sun
authors.forename: Wei
authors.initials: W
authors.lastname: You
authors.forename: Jing
authors.initials: J
authors.lastname: Dai
authors.forename: Guang-sen
authors.initials: GS
authors.lastname: Li
mesh_terms: D019175:DNA Methylation; D003924:Diabetes Mellitus, Type 2 / Q000235:genetics* / Q000378:metabolism; D005260:Female; D020022:Genetic Predisposition to Disease; D005947:Glucose / Q000235:genetics / Q000378:metabolism; D006801:Humans; D020738:Leptin / Q000097:blood / Q000235:genetics* / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D011401:Promoter Regions, Genetic
chemical_list: D020738:Leptin; D005947:Glucose