Vitamin B6 influences glucocorticoid receptor-dependent gene expression.

摘要: We have examined the influence of intracellular vitamin B6 concentration on glucocorticoid receptor function in HeLa S3 cells transfected with a glucocorticoid-responsive chloramphenicol acetyltransferase (CAT) reporter plasmid. CAT activity is induced from this plasmid specifically by hormones receptor-dependent manner. The pyridoxal phosphate, physiologically active form vitamin, was elevated supplementation culture medium synthesis precursor pyridoxine and lowered exposure to phosphate inhibitor 4-deoxypyridoxine. Analysis responsiveness revealed that concentrations suppressed amount glucocorticoid-induced whereas moderate deficiency enhanced level receptor-mediated gene expression. In contrast, modulation had no effect either basal derived not stimulated dexamethasone or two glucocorticoid-insensitive plasmids. modulatory effects occur without changes mRNA levels, protein concentration, steroid binding capacity receptor. These observations demonstrate selectively influences expression through novel mechanism does involve alterations ligand capacity.