To assess the ameliorating effects of vitamin D3 on inflammatory bowel disease in rats via Toll-like receptor 4/myeloid differential factor 88/nuclear kappa B signaling pathway. Thirty two were randomly assigned into Control group, model group (Vehicle group), low-concentration (vitamin low group) and high-concentration high group). The was constructed using 3 % dextran sodium sulfate given dif...

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...

Sertoli cell secretory activities are highly dependent on ion channel functions and critical to spermatogenesis. The steroid hormone 1alpha,25(OH)2-vitamin D3 (1,25(OH)2-D3) stimulates exocytosis in different cell systems by activating a nongenotropic vitamin D receptor (VDR). Here, we described 1,25(OH)2-D3 stimulation of secretion via Cl(-) channel activation in the mouse immature Sertoli cel...

Agonist stimulated [S]guanosine 5¢-c-thiotriphosphate ([S]GTPcS) binding autoradiography was established for the examination of dopamine-D2 ⁄D3 receptors in human brain sections. The distribution of G proteins activated by dopamine-D2 ⁄D3 receptors was studied in whole hemisphere cryosections. Dopamine stimulated [S]GTPcS binding in brain regions with high densities of dopamine D2-like receptor...

Nicotinamide, the amide derivative of vitamin B(3), cooperates with retinoic acid (RA), a form of vitamin A, and 1,25-dihydroxyvitamin D(3) (D3), to regulate cell differentiation and proliferation of human myeloblastic leukemia cells. In human myeloblastic leukemia cells, RA or D3 are known to cause MAPK signaling leading to myeloid or monocytic differentiation and G0 cell cycle arrest. In this...

Vitamin D3 is a promising preventative and therapeutic agent for prostate cancer, but its implementation is hampered by a lack of understanding about its mechanism of action. Upon treatment with 1a,25-dihydroxyvitamin D3 [1,25(OH)2D3, vitamin D3], the metabolically active form of vitamin D3, adult prostate progenitor/ stem cells (PrP/SC) undergo cell-cycle arrest, senescence, and differentiatio...

[(11)C]-(+)-PHNO is a D3 preferring PET radioligand which has recently opened the possibility of imaging D3 receptors in the human brain in vivo. This imaging tool allows characterisation of the distribution of D3 receptors in vivo and further investigation of their functional role. The specific [(11)C]-(+)-PHNO signal is a mixture of D3 and D2 components with the relative magnitude of each com...

BACKGROUND The three main vitamin D metabolizing enzymes, vitamin D3-25-hydroxylase (25-OHase, 25-hydroxylase), 25-hydroxyvitamin D3-1alpha-hydroxylase (1alpha-OHase, 1alpha-hydroxylase) and 25-hydroxyvitamin D3-24-hydroxylase (24-OHase, 24-hydroxylase), have been described in malignant breast tissue. This in vitro study aimed to obtain more information regarding the regulation of these enzymes...

The serine/threonine kinase Akt is a downstream target of dopamine receptor signaling that is inhibited/dephosphorylated in response to direct and indirect dopamine receptor agonists. Although pharmacological studies uncovered the involvement of D2-class dopamine receptors in Akt regulation, they did not identify the role of individual receptor subtypes in this process. Here we used knock-out m...