Search

ABSTRACT Objective This study aimed to investigate the association of plasma TNF-α, IL-6, and lL-10 levels and cytokine gene polymorphisms [TNF-α (-308 G→A), IL-6 (-174 C→G) and IL-10 (-1082 A→G, -819 T→C and -592 A→C)] in type 2 diabetes mellitus (T2DM) and obese patients. Subjects and methods One hundred and two T2DM patients and 62 controls were included in this study. Cytokine plasma levels were measured by the Cytometric Bead Array method. Genotyping was carried out by the polymerase chain reaction. Results IL-6 levels were significantly different between T2DM patients and controls. Interestingly, IL-6 levels were higher in T2DM patients with BMI > 30 kg/m2 compared with other patients and obese controls. The genotype and allele frequencies were similar between patients and controls. In the T2DM group, the SNP IL-10 -819 T/C showed a difference between the cytokine level and genotypes: IL-10 level in the TT genotype was significantly higher when compared to CC genotype. Conclusions These results suggest an association between IL-6 levels and obesity, and IL-10 levels and the SNP -819 T/C in T2DM. Knowledge of these variants in T2DM might contribute to a better understanding of the role of inflammation in the etiology and progression of this disease.

Background and Objectives: Vitamin D levels have been associated with a diversity of diseases, including obesity. Vitamin D presents a pleiotropic action, and can regulate insulin secretion and inflammatory responses. Vitamin D receptor (VDR) gene polymorphisms are involved in the gene expression regulation and have been associated with type 2 diabetes mellitus (T2DM). This study aimed to evaluate the association between the polymorphisms ApaI (rs7975232), BsmI (rs1544410), FokI (rs10735810), and TaqI (rs731236) in the VDR gene in people diagnosed with T2DM, and plasma 25-hydroxivitamin D levels [25(OH)D]. Materials and Methods: A total of 101 T2DM patients and 62 gender, age, and body mass index (BMI) matched non-diabetic controls were included in this study. Molecular analyzes were performed by polymerase chain reaction−restriction fragment length polymorphism (PCR-RFLP). The plasma 25(OH)D levels were measured by high performance liquid chromatography. Results: The plasma 25(OH)D levels were lower in T2DM patients (17.2 (16.6) ng/mL) when compared with the control subjects (30.8 (16.2) ng/mL, p < 0.0001), independently of obesity status. We found no difference between genotypic and allelic frequencies of the VDR polymorphisms when comparing the T2DM group and control group (p > 0.05 for all), and did not show any association with plasma 25(OH)D levels. Conclusions: These results suggest that T2DM is associated with lower plasma 25(OH)D levels, which are not related to BMI and VDR gene polymorphisms.