title: Elevated serum monocyte chemoattractant protein-1 levels and its genetic polymorphism is associated with diabetic retinopathy in Chinese patients with Type 2 diabetes.
abstract: OBJECTIVE
  Previous studies have reported that monocyte chemoattractant protein-1 (MCP-1) is involved in inflammatory and metabolic diseases. The purpose of this study is to investigate the role of MCP-1 in the pathogenesis of diabetic retinopathy (DR) in Han Chinese patients with Type 2 diabetes.
  
  
  METHODS
  Serum levels of MCP-1 protein in patients classified as diabetic without retinopathy (DWR) and DR, including NPDR and PDR, were assayed by enzyme-linked immunosorbent assay. Genomic DNA from 198 DWR patients, 176 NPDR patients and 143 PDR patients were genotyped by using a PCR restriction fragment length polymorphism (PCR-RFLP) assay.
  
  
  RESULTS
  MCP-1 serum levels were significantly higher in NPDR and PDR patients than in the DWR patients. The frequencies of the GG genotype and G allele of the single nucleotide polymorphism (SNP) were significantly increased in DR patients compared with DWR patients. Further subgroup analysis was performed to test whether there was an association between the PDR or NPDR and DWR groups. Significantly higher frequencies of the GG genotype and G allele were observed in PDR and NPDR patients compared with DWR patients. Furthermore, the 25 patients with PDR were divided into three groups according to the genotype of the tested SNP. The expression of the MCP-1 gene was higher in the GG genotype group compared with the other two groups.
  
  
  CONCLUSIONS
  The results suggested that the -2518 GG genotype and G allele of MCP-1 are associated with an increased risk of PDR in the Chinese Han population. This polymorphism may influence the expression of the MCP-1 gene, which may play an important role in the pathogenesis of DR.
authors.affiliation: Department of Ophthalmology, Second Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China.
authors.forename: Z
authors.initials: Z
authors.lastname: Jiang
authors.affiliation: Department of Ophthalmology, University of California San Francisco, San Francisco, USA.|University of California San Francisco, School of Medicine, San Francisco, USA.
authors.forename: L
authors.initials: L
authors.lastname: Hennein
authors.affiliation: Department of Ophthalmology, Second Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China.
authors.forename: Y
authors.initials: Y
authors.lastname: Xu
authors.affiliation: Department of Ophthalmology, Second Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China.
authors.forename: N
authors.initials: N
authors.lastname: Bao
authors.affiliation: Department of Ophthalmology, University of California San Francisco, San Francisco, USA.
authors.forename: P
authors.initials: P
authors.lastname: Coh
authors.affiliation: Department of Ophthalmology, Second Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China.
authors.forename: L
authors.initials: L
authors.lastname: Tao
mesh_terms: D020121:5' Untranslated Regions; D000328:Adult; D000483:Alleles; D044466:Asian People; D016022:Case-Control Studies; D018932:Chemokine CCL2 / Q000097:blood / Q000235:genetics* / Q000378:metabolism; D002681:China; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000150:complications* / Q000276:immunology / Q000378:metabolism; D003930:Diabetic Retinopathy / Q000097:blood / Q000235:genetics* / Q000276:immunology / Q000378:metabolism; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005786:Gene Expression Regulation; D056726:Genetic Association Studies; D020022:Genetic Predisposition to Disease; D006785:Hospitals, University; D006801:Humans; D008297:Male; D008875:Middle Aged; D012150:Polymorphism, Restriction Fragment Length; D020641:Polymorphism, Single Nucleotide; D015854:Up-Regulation
chemical_list: D020121:5' Untranslated Regions; C111835:CCL2 protein, human; D018932:Chemokine CCL2