title: Detection of autoantibodies against glycosylated-DNA in diabetic subjects: Its possible correlation with HbA(1C).
abstract: OBJECTIVE
  The vascular tissues have a long memory of their previous glycemic control and intervention studies have demonstrated that microvascular complications are highly correlated with mean glycemic control as measured by glycolated hemoglobin A₁C ( HbA₁c)The present study was carried out to evaluate the autoantibodies against glycosylated DNA (DNA-AGEs) in diabetic sera to see if the level of HbA1c has correlation with the activity of DNA-AGEs, another marker of chronic glycemia.
  
  
  METHODS
  Glucose-6-phosphate induced glycosylation of native DNA was studied in 150 diabetic sera (T1DM=9, T2DM=141) by spectroscopic techniques (UV and fluorescence) and agarose gel electrophoresis. Direct binding and inhibition enzyme immunoassays were carried out to evaluate binding and specificity of anti-glycated-DNA autoantibodies (anti-DNA-AGE autoantibodies) in sera of diabetes patients. A quantitative estimation of HbA₁c was carried out in normal and diabetes sera.
  
  
  RESULTS
  Anti-DNA-AGEs autoantibodies in 55% of diabetic sera (85/150) showed more binding with glycated-DNA compared to native DNA which was subjected to inhibition ELISA indicating true interaction of these autoantibodies in diabetes with glycated DNA. Higher binding with glycosylated-DNA against native-DNA was observed in subjects with HbA1c of 9.8 ± 3.3% compared to those with HbA1c of 7.7 ± 1.7% (p< 0.001). Linear correlation analysis showed that mean absorbance difference was significantly related to HbA1c (r=0.486, p< 0.001), nephropathy (r= 0.239, p< 0.003), retinopathy (r=0.165, p< 0.05).
  
  
  CONCLUSIONS
  Autoantibodies against glycosylated DNA were correlated with HbA₁c and microvascular complications and may be useful as another biomarker for assessment of chronic glycemia.
authors: Centre for Diabetes and Endocrinology, Jawaharlal Nehru Medical College, Aligarh Muslim University, U.P., India. jamalahmad11@rediffmail.com
authors: Jamal
authors: J
authors: Ahmad
authors: Anuj
authors: A
authors: Gupta
authors: Khursheed
authors: K
authors: Alam
authors: Khalid Jamal
authors: KJ
authors: Farooqui
mesh_terms: D000328:Adult; D000368:Aged; D000465:Algorithms; D001323:Autoantibodies / Q000032:analysis*; D015415:Biomarkers / Q000032:analysis; D001786:Blood Glucose / Q000032:analysis; D015992:Body Mass Index; D016022:Case-Control Studies; D004247:DNA / Q000032:analysis* / Q000378:metabolism; D003920:Diabetes Mellitus / Q000097:blood* / Q000378:metabolism; D004587:Electrophoresis, Agar Gel / Q000379:methods; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D005215:Fasting / Q000097:blood; D005260:Female; D019298:Glucose-6-Phosphate / Q000494:pharmacology; D006442:Glycated Hemoglobin / Q000032:analysis*; D006031:Glycosylation; D006801:Humans; D006973:Hypertension; D008297:Male; D008875:Middle Aged; D019518:Postprandial Period; D011485:Protein Binding; D013050:Spectrometry, Fluorescence / Q000379:methods
chemical_list: D001323:Autoantibodies; D015415:Biomarkers; D001786:Blood Glucose; D004247:DNA; D019298:Glucose-6-Phosphate; D006442:Glycated Hemoglobin