A low serum level of vitamin D has been associated with an increased incidence of gastrointestinal tract cancers. However, the effects of vitamin D3 have not been investigated in gastric cancer and cholangiocarcinoma. In the present study, we found that vitamin D3 treatment significantly suppressed the viability of gastric cancer and cholangiocarcinoma cells. Moreover, vitamin D3 had a synergis...

PURPOSE Vitamin D3 is a secosteroid mainly synthesized from the conversion of the skin precursor 7-dehydrocholesterol (7DHC) to vitamin D3 by ultraviolet (UV) B sunlight. Extrarenal synthesis of vitamin D3 has been reported in many tissues and cells, including barrier sites. This study characterizes the expression of components of vitamin D3 signaling in human ocular barrier cells. METHODS Pr...

Vitamin D deficiency has been associated with increased risk of colon cancer in epidemiologic and prospective clinical studies. In vitro and in vivo studies demonstrated that 1,25-dihydroxycholecalciferol [1,25(OH)2D3] and its analogs inhibit colon cancer cell proliferation. Few studies have evaluated the effect of vitamin D deficiency on the development and growth of colon cancer. To assess th...

1. The term vitamin D is used for a range of closely related steroid compounds which possess the property of preventing or curing vitamin D deficiency. These include alfacalcidol (1α-hydroxyvitamin D3), calcifediol (25-hydroxyvitamin D3), calcitriol (1α,25 dihydroxy-vitamin D3), cholecalciferol (vitamin D3), dihydrotachysterol and ergocalciferol (vitamin D2 or calciferol). In veterinary medicin...

Treatment of logarithmically growing rat intestinal epithelial cells (IEC-6) in culture with vitamin D3 (cholecalciferol), 25-hydroxy vitamin D3 (25-hydroxy cholecalciferol), 1,25-dihydroxy vitamin D3 (1,25-dihydroxycholecalciferol), and 24,25 dihydroxy vitamin D3 (24(R),25-dihydroxycholecalciferol), caused an inhibition of the cholesterol biosynthetic pathway at two separate sites. At concentr...

Vitamin D3-3 beta-sulfate has been synthesized using pyridine sulfur trioxide as the sulfate donor. It has been shown to be pure by high performance liquid chromatography and spectral methods. Unlike previous reports, the product has been identified unambiguously as the 3 beta-sulfate ester of vitamin D3 by its ultraviolet, nuclear magnetic resonance, infrared, and mass spectra. The biological ...

A variant of the chronic myelogenous leukemia cell line, RWLeu-4, that is resistant to the antiproliferative effects of vitamin D3 was established. Although RWLeu-4 proliferation is inhibited by 1 nmol/L vitamin D3, the resistant cells (JMRD3) continue to proliferate in the presence of 100 nmol/L vitamin D3. Both cells express similar patterns of differentiation-specific antigens after treatmen...

Aim: To prospectively evaluate the effects of vitamin D3 on disease activity and quality of life in ulcerative colitis (UC) patients with hypovitaminosis D. Methods: The study was a prospective double-blinded, randomized trial conducted at Community Regional Medical Center, Fresno, CA from 2012 2013. Patients with UC and a serum 25(OH)D level <30ng/ml were eligible for the study. Enrolled subje...