Flavohemoglobins metabolize nitric oxide (NO) to nitrate and protect bacteria and fungi from NO-mediated damage, growth inhibition, and killing by NO-releasing immune cells. Antimicrobial imidazoles were tested for their ability to coordinate flavohemoglobin and inhibit its NO dioxygenase (NOD) function. Miconazole, econazole, clotrimazole, and ketoconazole inhibited the NOD activity of Escheri...

This study investigated the effect of NaNO2 on inhibiting myoglobin-mediated lipid oxidation in muscle using a washed bovine mince model. We measured various parameters, including TBARS and PV to determine oxidation, non-heme iron release, protoporphyrin destruction, nitrosylmyoglobin production. The results showed that addition during significantly reduced fading (p < 0.05). Additionally, rele...

Up-regulation of CD4+CD25+CD127low/- regulatory T cells (Tregs) is a new target in the treatment of asthma. Human bone marrow mesenchymal stem cells can up-regulate CD4+CD25+CD127low/- regulatory T cells in vitro, meanwhile, heme oxygenase-1 (HO-1) plays an important role in the development and maintenance of CD4+CD25+ regulatory T cells. However the mechanism has not yet been adequately unders...

This review summarizes heme metabolism and focuses especially upon the control of hepatic heme biosynthesis. Activity of δ-aminolevulinic acid synthetase, the first enzyme of heme biosynthesis, is of primary importance in controlling the overall activity of this biosynthetic pathway. Δ-aminolevulinic acid synthetase is subject to inhibition and repression by heme, and numerous basic and clinica...

Wild-type Saccharomyces cerevisiae do not accumulate exogenous sterols under aerobic conditions, and a mutant allele conferring sterol auxotrophy (erg7) could be isolated only in strains with a heme deficiency. delta-Aminolevulinic acid (ALA) fed to a hem1 (ALA synthetase-) erg7 (2,3-oxidosqualene cyclase-) sterol-auxotrophic strain of S. cerevisiae inhibited sterol uptake, and growth was negat...

Tin-protoporphyrin is a potent competitive inhibitor of heme oxygenase both in vivo in animals and in vitro in isolated enzyme preparations, and when administered to neonatal rats, prevents the development of postnatal hyperbilirubinemia. In this study we examined the effect of the metalloporphyrin on the activity of heme oxygenase in liver, kidney, and spleen, and on the level of bilirubin in ...

Numerous disease states are associated with hemolysis or hemorrhage. Because red cells in the extravascular space tend to lyse quickly, hemoglobin (Hb) is released and is prone to autoxidation producing MetHb. Inorganic and organic peroxides may convert Hb and MetHb to higher oxidation states such as ferrylHb. FerrylHb is not a single chemical entity but is a mixture of globin- and porphyrin-ce...

Leukocytes arrested on inflamed endothelium via integrins are subjected to force imparted by flowing blood. How leukocytes respond to this force and resist detachment is poorly understood. Live-cell imaging with Lifeact-transfected U937 cells revealed that force triggers actin polymerization at upstream α4β1 integrin adhesion sites and the adjacent cortical cytoskeleton. Scanning electron micro...

Abstract Under hemolytic conditions, toxic heme is scavenged by hemopexin. Recently, the heme-binding properties of hemopexin have been reassessed, which revealed a K D ~ 0.32 nM as well stoichiometry one to two molecules binding A 66mer hemopexin-derived peptide that spans over three motifs was used verify earlier suggested heme-recruiting mechanism. Herein, we employed spectroscopic and compu...