Vitamin D deficiency will lead to insulin resistance. In the current study, vitamin D3 1α-Hydroxylase ["1α(OH)ase"] knockout mice were generated to mimic vitamin D deficiency in vivo. As compared to the wild-type mice, the liver tissues of the knockout mice showed impaired insulin signaling, decreased glucose transporter 4 expression and increased reactive oxygen species production. Meanwhile, ...

In this study, we characterized the effects of 25-hydroxyvitamin D3 (25-OH D3) and manipulated dietary cation-anion difference (DCAD) on the performance, urine pH, serum constituents, carcass traits, tissue residual vitamin D and its metabolites, beef tenderness, and mRNA and protein concentrations of Ca-dependent proteinases in LM using 24 cull native Korean cows. The cows were divided into 3 ...

Background:There is an increasing prevalence of type 2 diabetes mellitus (T2DM) worldwide. The deficiency vitamin D a worldwide health problem that can increase susceptibility to T2DM. Cytochrome P450 family 27 subfamily B member 1 (CYP27B1) encodes the enzyme 1α-hydroxylase in kidney, which converts 25 (OH)-D3 1,25 (OH)2-D3. CYP27B1 rs10877012 G/T polymorphism located gene promoter and influen...

The active vitamin D metabolite 1α,25-dihydroxyvitamin D3 (1,25(OH)2D3) has important regulatory actions in the gut through endocrine and probably also intracrine, autocrine and paracrine mechanisms. By activating the vitamin D receptor (VDR), which is expressed at a high level in the small intestine and colon, 1,25(OH)2D3 regulates numerous genes that control gut physiology and homeostasis. 1,...

The 25-hydroxyvitamin D3 (25-OH-D3) is a nontoxic and low-affinity vitamin D receptor (VDR)-binding metabolic precursor of 1,25-dihydroxyvitamin D3 [1,25(OH)2D3]. We hypothesized that covalent attachment of a 25-OH-D3 analog to the hormone-binding pocket of VDR might convert the latter into transcriptionally active holo-form, making 25-OH-D3 biologically active. Furthermore, it might be possibl...

We previously found a weak response in serum 25-hydroxyvitamin D3 (25(OH)D3) concentrations when dogs were supplemented with oral vitamin D3 (D3). In the present study, we determined the relative potency of oral 25(OH)D3 compared with D3 for increasing vitamin D status in dogs with low serum 25(OH)D concentrations. Four male and three female, 4-year-old, intact, lean, genetically related, Chine...

Cholate-solubilized chick kidney mitochondria that 1-hydroxylated 25-hydroxyvitamin-D3 (25-OH-D3) upon reconstitution also produced 10-oxo-19-nor-25-OH-D3, which co-eluted with 1,25-dihydroxyvitamin D3 (1,25-(OH)2-D3) on normal phase high performance liquid chromatography (HPLC) with hexane:propanol-2 (9:1), the traditional chromatographic system for isolating 1,25-(OH)2-D3. The 10-oxo derivati...

The most biologically active metabolite 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) has well known direct effects on osteoblast growth and differentiation in vitro. The precursor 25-hydroxyvitamin D3 (25(OH)D3) can affect osteoblast function via conversion to 1,25(OH)2D3, however, it is largely unknown whether 25(OH)D3 can affect primary osteoblast function on its own. Furthermore, 25(OH)D3 is not o...

AIM Altered vitamin D signaling is associated with cardiac dysfunction, but the pathogenic mechanism is not clearly understood. We examine the mechanism and the role of vitamin D signaling in the development of cardiac dysfunction. METHODS AND RESULTS We analyzed 1α-hydroxylase (1α-OHase) knockout (1α-OHase-/-) mice, which lack 1α-OH enzymes that convert the inactive form to hormonally active...

For a global understanding of the physiological impact of the nuclear hormone 1α,25-dihydroxyvitamin D3 (1,25(OH)2D3) the analysis of the genome-wide locations of its high affinity receptor, the transcription factor vitamin D receptor (VDR), is essential. Chromatin immunoprecipitation sequencing (ChIP-seq) in GM10855 and GM10861 lymphoblastoid cells, undifferentiated and lipopolysaccharide-diff...