Serum Vitamin D Status, Vitamin D Receptor Polymorphism, and Glucose Homeostasis in Healthy Subjects

Abstract

Low vitamin D status has been frequently associated with impaired glucose metabolism. We examined associations between 25-hydroxyvitamin D (25-OH-D) and several parameters of glucose homeostasis in virtually healthy subjects, and explored possible interaction with vitamin D receptor (VDR) polymorphism. Nondiabetic subjects without chronic medication or any known significant manifest disease were selected from large general-population based population survey. Insulin sensitivity and β cell secretion were calculated by homeostasis model assessment (HOMA) and soluble isoform of receptor for advanced glycation end-products (sRAGE) using commercial ELISA. Subjects were also genotyped for rs2228570 polymorphism of VDR. After adjustment for potential confounders, we observed a significant relationship between 25-OH-D and fasting glycemia (β coefficient=-5.904; p=0.002) or insulin sensitivity (β=0.042; p=0.001), but not with β cell secretion or sRAGE. We found also an interaction with VDR polymorphism. Subjects with low 25-OH-D and genotype had significantly lower insulin sensitivity than those with genotype plus highest 25-OH-D concentrations (107.3% vs. 183.9%, p=0.021). In conclusion, low vitamin D status was in virtually healthy subjects associated with decreased insulin sensitivity, namely in those with genotype of rs2228570 VDR polymorphism.

Severe Vitamin D3 Deficiency in the Majority of Patients with Diabetic Foot Ulcers

“…Wound healing is impaired in diabetic patients while vitamin D is essential for a normal functioning immune system [33][34][35]. CD8 positive T-cells and natural killer cells are targets for vitamin D [36].…”

“…Calcium, creatinine, and parathyroid hormone were measured in patients with diabetic foot ulcers. The data were analysed together with glycosylated hemoglobin A1c and the severity of diabetic foot lesions according to the Armstrong [7][8][9][10][11][12]. Until now, there are only scarce data regarding 25-hydroxyvitamin D 3 status in patients with diabetic foot ulcer [13].…”

Correlation of Vitamin D with Inflammatory Cytokines, Atherosclerotic Parameters, and Lifestyle Factors in the Setting of Heart Failure: A 12-Month Follow-Up Study

“…The high prevalence of vitamin D deficiency throughout the 12-month follow-up shown in our cohort of patients with HF may thus worsen or predispose them to alterations in glucose metabolism. Moreover, a significant correlation between 25(OH)D levels < 43 ng/mL and impaired fasting glucose (OR = 3.40) and low insulin sensitivity (defined as HOMA index for insulin sensitivity < 90%) (OR = 2.65) has been reported in healthy adults with a median age of 39.4 years old [42]. Specifically, in patients with HF, vitamin D deficiency was shown to be correlated with increased rates of diabetes mellitus when compared with a non-vitamin D deficient group (31.4% vs. 22.8%) [43].…”

Associations between vitamin D status and diabetic complications in Chinese population with type 2 diabetes mellitus: a cross-sectional study

“…Regardless of this contradiction, many lines of evidence supported the favorable effects of vitamin D on DFU, especially on wound healing, which is impaired in diabetic patients due to persistent inflammation [72]. Vitamin D is essential in maintaining the normal immune system [73,74]. Vitamin D could suppress T cell proliferation and inhibit the secretion of T helper type 1 cytokines (e.g., interferon-γ and interleukin-2), while augmenting the production of T helper type 2 cytokines [75], thereby accelerating wound healing.…”