Association between alterations in global DNA methylation and predisposing factors in diabetes: a high pressure liquid chromatography based study.

AIM: The aim of this study was to investigate the relationship between inter-individual global DNA methylation and diabetes predisposing factors. METHODS: The 5-methyl cytosine content was assessed by reverse phase high pressure liquid chromatography (RP-HPLC) of peripheral blood leukocytes obtained from 178 type 2 diabetes patients to determine individual global DNA methylation status. RESULTS: There was a positive significant correlation between diabetes duration and DNA methylation levels (P=0.002) with increasing levels of DNA methylation associated with age (P=0.047). There was no significant correlation between DNA methylation levels and HbA1c (P=0.15). No significant differences were observed between patients with and without diabetes predisposing factors including: hypertension (P=0.772), dyslipidemia (P=0.617), insulin resistance (homeostatic model assessment index) (P=0.156) and obesity (P=0.609). As such, the duration of diabetes (>10 years) was the most important predictor of global DNA methylation levels in diabetic patients after adjusting for age and sex (P=0.023). CONCLUSION: Our findings indicate that chronic hyperglycemic exposure plays an independent role in global DNA methylation levels in type 2 diabetes patients.

Cytokine profile, Foxp3 and nuclear factor-kB ligand levels in multiple sclerosis subtypes.

AIM: Patients with multiple sclerosis (MS) present with heterogeneous clinical courses. To elucidate whether different immunopathological mechanisms are involved in MS subgroups, we compared serum levels of TNF-α, IL-1ß, hs-CRP, receptor activator of nuclear factor kappa-B ligand (RANKL) and peripheral blood foxp3 expression in clinical subtypes of MS (relapsing remitting: RR-MS; secondary progressive: SP-MS; primary progressive: PP-MS) and healthy subjects. METHODS: In a case-control study, 72 healthy individuals and 72 age- and sex-matched multiple sclerotic patients (57% RR-MS, 18% SP- MS and 25% PP-MS) were evaluated. The age, gender distribution, and BMI of MS patients in these three sup-types were similar. The serum levels of TNF-α, IL-1ß, and RANKL were measured by ELISA. hs-CRP was measured by imunoturbidimetric method. Peripheral blood mononuclear cells expression of Foxp3 was measured by real time PCR. RESULTS: A significant elevation of TNF-α, hs-CRP, IL-1ß and RANKL and diminution of Foxp3 expression in MS patients compared to control was found (P<0.001). PP-MS had highest levels of TNF-α, IL-1ß, CRP and RANKL, and lowest levels of foxp3, with difference in TNF-α reached significant level (P<0.01). RANKL and TNF-α showed a reverse (P<0.01) significant correlation with Foxp3 relative expression levels. Patients with early age onset (onset before 30 years) had significantly higher levels of hs-CRP compared to late age onset patients. CONCLUSION: These data demonstrate the presence of immunopathogenesis differences between relapsing and non-relapsing form and is also the first to stress a role for cytokine RANKL in MS patients.

Genetic variation in macrophage migration inhibitory factor associated with gestational diabetes mellitus and metabolic syndrome.

The aim of this study was to investigate the association of macrophage migration inhibitory factor (MIF) polymorphism rs1007888 with gestational diabetes mellitus (GDM), and its association with postpartum metabolic syndrome. In a case-control study, 147 GDM and 169 healthy pregnant patients were recruited. Blood sample was taken 2 times from all the participants; one at 24-28 weeks of gestation, second at 6-12 weeks of postpartum. Biochemical measurement and DNA extraction were performed. The PCR_SSP was performed for genotyping. The frequencies of AA, AG, and GG genotypes were 11.24% (19), 76.92% (130), and 11.83% (20) in healthy pregnancies and were 7.48% (11), 70.74% (104), and 21.76% (32) in GDM individuals. The distributions of MIF genotypes were significantly different in GDM and healthy subjects (p=0.04). Moreover, GG genotype had a significant association with pre-pregnancy obesity and family history of diabetes. In postpartum follow-up GG genotype was two-fold more frequent in women with metabolic syndrome (p=0.01, odds ratio=2.30, CI 95%; 1.23-4.30) and relative risk was equal 1.77 (CI 95%; 1.19-2.64). Our findings demonstrate an association between MIF polymorphism rs1007888 and susceptibility to GDM in pregnancy and metabolic syndrome development.

Relationship between leptin concentration and insulin resistance.

Available evidences suggest that leptin has inhibitory role on insulin secretion. The aim of the work was to examine the association between plasma leptin concentrations and insulin resistance in patients with gestational diabetes mellitus. As a cross-sectional study we recruited 741 pregnant women. The universal screening was performed with an oral glucose challenge test-50 g. The recruits with plasma glucose levels of > or = 7.2 mmol/l were diagnosed as having gestational diabetes mellitus if they had an impaired oral glucose tolerance test-100 g based on Carpenter and Coustan criteria. In all pregnancies plasma insulin and leptin concentrations were measured. Gestational diabetes mellitus developed in 7% (52) of pregnancies. Elevated leptin concentrations were positively associated with insulin levels, BMI, and HOMA index while it was negatively associated with Quicky index. After adjusting for age and BMI before pregnancy, gestational diabetes mellitus had independent direct correlation with leptin concentration. Indeed, leptin level equal to or more than 20 ng/ml could help to predict the developing gestational diabetes mellitus. Measurement of leptin together with the assessment of other risk factors could help identifying women at risk of developing GDM.