title: A study on the correlation between MTHFR promoter methylation and diabetic nephropathy.
abstract: OBJECTIVE
  In order to observe the relationship between MTHFR promoter and DN, the determinations on MTHFR promoter methylation level and expression of HCY from DN patients have been carried out.
  
  
  METHODS
  According to the Diabetes diagnosis and classification standard from WHO in 1999, 85 patients with DM diagnosed by Endocrinology and 30 healthy participants from our medical examination center were chosen as control specimen to study in this paper. All this specimen were divided into A, B, C and D four groups , which are corresponding simple diabetes mellitus group (SDM), early diabetic nephropathy group (EDN), clinical diabetic nephropathy group (CDN) and normal control group. And then, all common materials and clinical experiments data have been collected respectively. (1) Extracted the peripheral blood DNA of each group and determinate the methylation status of MTHFR gene promoter by PCR (MSP). (2) Determinated the serum HCY protein expression of each group.
  
  
  RESULTS
  (1) The MTHFR promoter methylation of SDM and diabetic nephropathy group are wear off comparied with normal control group. And MTHFR promoter was in demethylation state in normal control group, a slightly weak in SDN, a obviously weak in early diabetic nephropathy group; the MTHFR promoter was in methylation state in clinical diabetic nephropathy group. (2) The HCY protein of simple diabetes mellitus group, early diabetic nephropathy group and clinical diabetic nephropathy group are Pitch with normal control group. HCY protein level of each group are as 7.41±1.61 umol/L, 10.34±2.89 umol/L, 10.95±5.89 umol/L and 13.03±6.14 umol/L corresponding normal control group, simple diabetes mellitus group, early diabetic nephropathy group and clinical diabetic nephropathy group. And there is no statistical significance about the differences among four groups.
  
  
  CONCLUSIONS
  The demethylation state of MTHFR promoter was obviously weaker in clinical diabetic nephropathy group than in SDM. The level of serum HCY was obviously higher in clinical diabetic nephropathy group than in SDM. It suggested that MTHFR promoter demethylation may be involoed in the pathogenesis of DN.
authors.affiliation: Department of Endocrinology, Affiliated Zhongshan Hospital of Dalian University Dalian 116001, China.
authors.forename: Xiao-Hui
authors.initials: XH
authors.lastname: Yang
authors.affiliation: Department of Outpatient, The Royal Hong Kong Slow Disease Hospital Dalian, China.
authors.forename: Ren-Fang
authors.initials: RF
authors.lastname: Cao
authors.affiliation: Department of Endocrinology, Affiliated Zhongshan Hospital of Dalian University Dalian 116001, China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Yu
authors.affiliation: Department of Endocrinology, Affiliated Zhongshan Hospital of Dalian University Dalian 116001, China.
authors.forename: Miao
authors.initials: M
authors.lastname: Sui
authors.affiliation: Department of Endocrinology, Affiliated Zhongshan Hospital of Dalian University Dalian 116001, China.
authors.forename: Tao
authors.initials: T
authors.lastname: Zhang
authors.affiliation: Department of Endocrinology, Affiliated Zhongshan Hospital of Dalian University Dalian 116001, China.
authors.forename: Jing-Yi
authors.initials: JY
authors.lastname: Xu
authors.affiliation: Department of Endocrinology, Affiliated Zhongshan Hospital of Dalian University Dalian 116001, China.
authors.forename: Xiao-Mei
authors.initials: XM
authors.lastname: Wang
keywords: DNA methylation; Diabetes meilltus; diabetic nephropathy; homocysteine; methylenetetrahydrofolate reductase