Methods: The prevalence of multiple sclerosis (MS) is high in patients suffering from 25-hydroxyvitamin D3 [25(OH)D] deficiency. The aim of this study was to investigate the possible association of saliva and serum 25(OH)D concentrations with MS in women.Methods: Serum and saliva 25(OH)D levels of 30 MS women and 30 matched healthy controls in this case-control study were measured by ELIS...

BACKGROUND AND AIM The aim of this study was to compare unstimulated whole saliva 25-hydroxycholecalciferol (25(OH)D) in menopausal women with and without oral dryness (OD) feeling, and evaluate the relationship between saliva 25(OH)D and severity of OD feeling. METHODS A case-control study was carried out on 70 selected menopausal women aged 41-77 years with or without OD feeling (35 as case...

Actinomycin D (or cycloheximide) administered prior to radioactive 25-hydroxycholecalciferol blocks the metabolism of 25-hydroxycholecalciferol to polar metabolites that accumulate in intestinal tissue, while it does not prevent the 25-hydroxylation of vitamin D(3) in the liver. Actinomycin D given after radioactive 25-hydroxycholecalciferol does not inhibit 25-hydroxycholecalciferol metabolism...

Vitamin D is a fat-soluble vitamin with hormonal functions, which helps in calcium and phosphate homeostasis bone metabolism. Beyond the role health, influences non-skeletal health problems chronic diseases like obesity, hypertension, cardiovascular diseases, glucose intolerance type 2 diabetes mellitus (T2DM). Low impairs insulin synthesis secretion resulting T2DM. This study was carried out b...

1. In subjects with normal renal function there was a strong positive correlation between serum concentrations of 25-hydroxycholecalciferol and 24,25-dihydroxycholecalciferol, as measured by competitive protein-binding assay. 2. The 24,25-dihydroxycholecalciferol concentration was about 7% of the prevailing 25-hydroxycholecalciferol concentration. 3. In contrast, sera from anephric patients con...

Primary cultures of chick kidney cells convert 25-hydroxycholecalciferol into more-polar metabolites. Cells from vitamin D-deficient chicks have high 25-hydroxycholecalciferol 1 alpha-hydroxylase (1 alpha-hydroxylase) activity, but no 25-hydroxycholecalciferol 24-hydroxylase (24-hydroxylase) activity. Physiological concentrations of 1,25-dihydroxycholeclaciferol suppress 1 alpha-hydroxylase and...

In the context of the global prevalence of vitamin D insufficiency, we compared two key determinants of the bioavailability of 3 vitamin D forms with significant biopotencies: cholecalciferol, 25-hydroxycholecalciferol and 1-α-hydroxycholecalciferol. To this aim, we studied their incorporation into synthetic mixed micelles and their uptake by intestinal cells in culture. Our results show that 1...

Early detection and surgery represent the mainstay of treatment for superficial melanoma, but for high risk lesions (Breslow's thickness >0.75 mm) an effective adjuvant therapy is lacking. Vitamin D insufficiency plays a relevant role in cancer biology. The biological effects of 1α hydroxycholecalciferol on experimental melanoma models were investigated. 105 melanoma patients were checked for 2...

The side chain of vitamin D3 is hydroxylated in a sequential manner by cytochrome P450scc (CYP11A1) to form 20-hydroxycholecalciferol, which can induce growth arrest and differentiation of both primary and immortalized epidermal keratinocytes. Since nuclear factor-kappaB (NF-kappaB) plays a pivotal role in the regulation of cell proliferation, differentiation and apoptosis, we examined the capa...

Background: Susceptibility to disease after infection by Mycobacterium tuberculosis is influenced by environmental and host genetic factors. Vitamin D metabolism leads to activation of macrophages and restricts the intracellular growth of M tuberculosis. This effect may be influenced by polymorphisms at three sites in the vitamin D receptor (VDR) gene. We investigated the interaction between se...