Selenium-dependent peroxidases suppress 5-lipoxygenase activity in B-lymphocytes and immature myeloid cells. The presence of peroxidase-insensitive 5-lipoxygenase activity in differentiated myeloid cells.

摘要: Differentiation of HL-60 cells by dimethylsulfoxide induces 5-lipoxygenase protein expression, but only low cellular activity. Similarly, B-lymphocytes express and show activity in cell homogenates not intact cells. Here, we demonstrate that suppression these lines is serum dependent the effect can be mimicked selenium. Selenium-dependent inhibition was also observed corresponding or 100,000 x g supernatants when dithiothreitol glutathione (GSH) added. The properties endogenous selenium-dependent inhibitor, i.e., molecular mass, utilization GSH as substrates, sensitivity to iodacetate, presence GPx-1 inhibitor mercaptosuccinate, suggest a selenoenzyme with phospholipid hydroperoxide peroxidase (GPx-4) responsible for BL41-E95-A immature 1,25-dihydroxyvitamin D3 transforming growth factor-beta (TGF beta) upregulated regardless whether were grown without Also, D3/TGF beta differentiated human granulocytes inhibited GSH. Thus, after differentiation, resemble normal respect high effects broken preparations. Combination experiments 100000 neutrophils revealed due stability catalytic against peroxidases, Our data capability mature myeloid release large amounts leukotrienes stimulation peroxidase-insensitive