Analysis of Expression and DNA Methylation Patterns of Adipolin Gene in Type 2 Diabetes

Abstract

Type 2 Diabetes Mellitus is a complex metabolic disorder that is characterized by hyperglycemia and peripheral insulin resistance. In year 2005, 170 million individuals were reported to be suffering from diabetes with causative factors being genetic, environmental and epigenetic. Adipolin is an adipocyte reported to be involved in insulin sensitization and reduction in inflammation. Its expression has been previously found to be downregulated in diet induced obese mouse models. Present study aimed to investigate any alteration in the levels of adipolin in human patients of type 2 diabetes in comparison with healthy controls. Also it aimed to determine if DNA methylation has a part to play in variation of expression. Adipose tissue biopsies of type 2 diabetes patients and healthy controls were collected. Quantitative analysis of adipolin mRNA expression was performed and compared with mRNA levels in control biopsy samples. To analyze DNA methylation status of adipolin promoter region Methylation Specific PCR was carried out. Patients suffering from type 2 diabetes had significantly low levels of adipolin mRNA in comparison to healthy controls. However, Methylation Specific PCR revealed that CpG islands present in the promoter region of patients as well as controls were unmethylated. From this study it maybe concluded that factors other than methylation on the promoter region of adipolin gene are responsible for its suppression and further studies are required to elucidate them.