Heme oxygenase 1 (HO-1) inhibits apoptosis by regulating cellular prooxidant iron. We now show that there is an additional mechanism by which HO-1 inhibits apoptosis, namely by generating the gaseous molecule carbon monoxide (CO). Overexpression of HO-1, or induction of HO-1 expression by heme, protects endothelial cells (ECs) from apoptosis. When HO-1 enzymatic activity is blocked by tin proto...

Hemeoxygenase (HO) system is responsible for cellular heme degradation to biliverdin, iron, and carbon monoxide. Two isoforms have been reported to date. Homologous HO-1 and HO-2 are microsomal proteins with more than 45% residue identity, share a similar fold and catalyze the same reaction. However, important differences between isoforms also exist. HO-1 isoform has been extensively studied ma...

OBJECTIVE It was reported that some effects of pentoxifylline (PTX) are mediated by heme oxygenase-1 (HO-1) induction. We investigated the role of HO-1 in anti-inflammatory activity of PTX. METHODS Experiments were performed in human and murine monocytes and endothelial cells and in HO-1 deficient mice. RESULTS PTX dose-dependently decreased expression of HO-1 in cell lines studied. As expe...

The final step in heme utilization and iron acquisition in many pathogens is the oxidative cleavage of heme by heme oxygenase (HO), yielding iron, biliverdin, and carbon monoxide. Thus, the essential requirement for iron suggests that HO may provide a potential therapeutic target for antimicrobial drug development. Computer-aided drug design (CADD) combined with experimental assays identified s...

Limited data is available regarding heterotopic ossification (HO) after cervical disc replacement (CDR). The goal of this study was to determine the incidence of HO after CDR with the Mobi-C artificial disc to identify the risk factors for HO, and to investigate whether HO affects clinical outcome and range of motion (ROM). Seventy one patients were included in this study. The mean follow-up wa...

Human bone marrow mesenchymal stem cells (MSC) are pleiotropic cells that differentiate to either adipocytes or osteoblasts as a result of cross-talk by specific signaling pathways including heme oxygenase (HO)-1/-2 expression. We examined the effect of inducers of HO-1 expression and inhibitors of HO activity on MSC differentiation to the osteoblast and adipocyte lineage. HO-1 expression is in...

The aim of the present study was to investigate the presence of heme oxygenase (HO)-1 and HO-2 in human endometrium at various stages of the menstrual cycle using RT-PCR, Western blotting, and immunohistochemistry. RT-PCR detected mRNA for HO-1 and HO-2 in human endometrium at all stages of the menstrual cycle. Western blotting also revealed the expression of the two distinct HO proteins throug...

Insulin resistance, with adipose tissue dysfunction, is one of the hallmarks of metabolic syndrome. We have reported a metabolic syndrome-like phenotype in heme oxygenase (HO)-2 knockout mice, which presented with concurrent HO-1 deficiency and were amenable to rescue by an EET analog. Apo A-I mimetic peptides, such as L-4F, have been shown to induce HO-1 expression and decrease oxidative stres...

The light-dependent production of hydroxyl radicals (HO*) by thylakoids, chloroplasts and leaves of Spinacia oleracea was investigated using dimethylsulfoxide as HO' trapping agent. Maximum rates of HO' production by thylakoids as indicated by the formation of methane sulfinic acid were observed under aerobic conditions in the absence of added electron acceptors. They were higher than 2 /anol (...