Biochemical and molecular study on interleukin-1 gene expression and relation of single nucleotide polymorphism in promoter region with Type 2 diabetes mellitus

Interleukin-1 (IL-1) assumes a centric role in the regulation of immune and inflammatory responses and thus has been recognized in immune mediated diseases like type 2 diabetes mellitus (T2DM). We aimed to investigate expressed level of IL-1 and its relation with IL-1 -511T>C polymorphism in T2DM patients. This study enrolled 80 subjects (50 patients with T2DM and 30 healthy control subjects). Laboratory investigations included fasting (FBG) and 2h postprandial blood sugar (2h PBG), HBA1c, lipid profile, and renal function tests. Genotyping of IL-1 -511T>C (rs16944) SNP assay by real-time PCR and relative quantitation of IL-1 gene expression transcript by real-time PCR. Results: T2DM patients had significantly higher FBG and 2h PBG, HBA1c, LDLc, TC, TG, systolic, and diastolic BP while lower HDLc compared with control group. IL 1- -511 T>C, CC genotype and C allele were significantly associated with risk of T2DM with odds ratio (OR) 4.73, 95%CI (1.21-18.39) and OR 2.27, 95%CI (1.72-4.40), respectively. Moreover, diabetic patients had significantly higher IL 1- gene transcript compared with control group (P<0.001). CC genotype of IL 1- -511 T > C had the highest significant level of IL 1- gene transcript demonstrated compared with C/T and T/T genotypes (P<0.001) in patients. Conclusion: C allele of IL-1 -511 T >C could be considered risk factor contributor to T2DM and excess level of IL-1 transcript may disclose to some degree the inflammatory role of cytokines in T2DM.