Introduction: Adenosine receptors (ARs), belonging to the G-protein-coupled receptors (GPCRs), are present in the majority of human cells and tissues. Depending on their biochemical and pharmacologic properties, four subtypes of ARs (i.e. A₁, A_2A, A_2B, and A₃) have been distinguished. Currently, these receptors are attractive molecular targets for pharmacological interventions in various diseases, including diabetes. The literature published to date has shown an altered expression of ARs in several types of cells under diabetic conditions. However, there has been no publication devoted to the investigation of ARs expression in leukocytes of subjects with gestational diabetes mellitus (GDM). Therefore, this study was aimed to determine the expression level of AR subtypes in leukocytes of GDM patients and its relationship to anthropometric and biochemical parameters.
Material and methods: Gene expression of four AR subtypes in leukocytes of both healthy (n = 34) and GDM (n = 67) subjects in the third trimester of pregnancy (from 24 to 33 weeks) was investigated. Multiple regression analyses were used to assess the association between the expression level of ARs and both anthropometric and biochemical parameters.
Results: Statistically significant (p < 0.05) higher levels of A_2A and A_2B mRNAs were observed in leukocytes of the GDM subjects compared to the control group. There was a positive correlation of A_2B mRNA level with glucose concentration at 120 min of oral glucose tolerance test (OGTT) (r = 0.24, p = 0.041).
Conclusions: Overexpression of A2BAR in leukocytes of the GDM subjects and, additionally, the existence of a relationship between its elevated expression level in these cells and abnormal values of glucose concentration at 120 min of OGTT for GDM, suggest that this subtype might be involved in the pathogenesis of GDM. (Pol J Endocrinol 2012; 63 (2): 110–114)