Vitamin D receptor gene polymorphisms in type 1 diabetes mellitus: a new pattern from Khorasan province, Islamic Republic of Iran

Reported associations between vitamin D receptor [VDR] polymorphism and type 1 diabetes mellitus vary across ethnic groups. We studied the association between type 1 diabetes and 4 VDR gene polymorphisms [Bb, Ff, Aa and Tt] in an Iranian population. A group of 69 patients with type 1 diabetes mellitus and 45 unrelated healthy subjects were recruited. The prevalence of VDR polymorphisms in 4 restriction fragment length polymorphism sites including BsmI, FokI, ApaI and TaqI were analysed in patients and controls. The frequencies of 3 genotypes [Aa, FF and Bb] were significantly higher in the patient group. The relationship between VDR gene polymorphisms and onset pattern of diabetes was not significant. There were no significant difference between the genotype frequencies and chronic complications of diabetes, but the relationship between the Ff genotype and ketoacidosis was significant. Our results differ from previous polymorphism studies in other regions

Serum 25 hydroxy vitamin d3 and laboratory risk markers of cardiovascular diseases in type 2 diabetic patients

Vitamin D deficiency is prevalent worldwide. Low 25 hydroxyvitamin D3 concentration is inversely associated with type 2 diabetes, metabolic syndrome, insulin resistance, and probably cardiovascular disease. The objective of this study was to evaluate of association between vitamin D deficiency and cardiovascular risk factors among diabetic patients. This cross-sectional study, which investigated 119 type 2 diabetes patients, was conducted in Mashhad between December 2007 and March 2008. Coronary, cerebrovascular and peripheral vascular diseases in the subjects were confirmed, and blood biochemical parameters, including laboratory risk markers of cardiovascular disease were determined. Serum 25 [OH] D was measured during winter to determine the correlation between vitamin D deficiency and cardiovascular prevalent and the laboratory variables. Mean patient age was 55.3 +/- 11.2 years. Mean 25 [OH] D concentration was 32.4+21.6 ng/ml. Prevalence of vitamin D level / deficiency D was 26.1% among diabetic patients, difference with control group not being significant [P=0.12]. Overall, 36 [30.3%] patients were positive for coronary vascular disease [CVD]. The correlation between hypovitaminosis D and CVD was not significant [p=0.11]. Patients with vitamin D deficiency had significant differences in body mass index [P=0.003], metabolic syndrome [P=0.05], high sensitive CRP [P=0.009], microalbuminuria [P=0.04], and glumerolar filtration rate [P=0.02] compared with patients with sufficient vitamin D; FBS, HbAiC, lipid profiles, homocysteine, uric acid and insulin resistance were not related to vitamin D deficiency. Results showed an association between hypovitaminous D and coronary risk markers indicating the importance of this vitamin in cardiovascular health

[Correlation between serum zinc level with impaired glucose tolerance and insulin resistance in major thalassemic patients]

Diabetes mellitus in thalassemic major patients is common. It is usually caused by secondary hemosiderosis but a long period of insulin resistance may be occur before occurrence of overt diabetes. Zinc deficiency, also common in thalassemic patients, it seems aggravates abnormal glucose metabolism in such patients. The aim of this study was to determine serum zinc level and the contributory effect of zinc deficiency on insulin resistance and glucose intolerance in thalassemic patients in Mashhad city. This descriptive study was conducted on patients with thalassemia major. Patients with diabetes, using medicines that interfere with serum zinc [except for iron chelators] and glucose levels were excluded. Blood samples for assessment of glucose, insulin, zinc, ferretin, albumin, PT, PTT levels were obtained and a standard glucose tolerance test was performed for all patients. Insulin resistance was calculated by the homeostatic model assessment of insulin resistance [HOMA- IR]. Complete insulin resistance was defined complete in HOMA- IR>3.9, partial in HOMA- IR between 2.5-3.9 and normal in HOMA- IR<2.5. Of the 109 thalassemic patients were enrolled, 4 [3.66%] patients had impaired glucose tolerance test, 2 [1.83%] had diabetes and the remaining were normal. The prevalence of zinc deficiency was 38.5% in our patients. Mean serum zinc level in diabetic patients was 88.2 +/- 2.9 micgr/dl and in non-diabetic patients was 84.2 +/- 14.9 [p=0.34]. After exclusion of diabetic patients, insulin resistance was very high in the remaining patients. Of these, 68 [63.5%] of patients had complete insulin resistance, 31[28.9%] had partial resistance and only 8 [7.47%] had normal insulin sensitivity. No significant difference was found in ferretin levels, age and sex, between diabetic and non-diabetic patients [p=0.93, 0.35, 0.28 respectively]. A significant reverse correlation was found between serum zinc level and fasting blood sugar [p=0.002] and serum ferretin level [p=0.05]. The correlation with other variables was not significant. Zinc deficiency and insulin resistance are prevalent in thalassemic patients but no association was found between zinc deficiency and occurrence of diabetes in our study population