Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P02794 (ferritin)
 17,525 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The rejection of concordant xenografts, such as mouse-to-rat cardiac xenografts, is very similar to the delayed rejection of porcine-to-primate discordant xenografts. In concordant models, this type of rejection is prevented by brief complement inhibition by cobra venom factor (CVF) and sustained T-cell immunosuppression by cyclosporin A (CyA). Mouse hearts that survive indefinitely in rats treated with CVF plus CyA express the anti-inflammatory gene heme oxygenase-1 (HO-1) in their endothelial cells and smooth muscle cells. The anti-inflammatory properties of HO-1 are thought to rely on the ability of this enzyme to degrade heme and generate bilirubin, free iron and carbon monoxide. Bilirubin is a potent anti-oxidant, free iron upregulates the transcription of the cytoprotective gene, ferritin, and carbon monoxide is thought to be essential in regulating vascular relaxation in a manner similar to nitric oxide. We show here that the expression of the HO-1 gene is functionally associated with xenograft survival, and that rapid expression of HO-1 in cardiac xenografts can be essential to ensure long-term xenograft survival.
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PMID:Expression of heme oxygenase-1 can determine cardiac xenograft survival. 973 4

Heme oxygenase-1 (HO-1) cleaves the porphyrin ring of heme into carbon monoxide, Fe2+, and biliverdin, which is then converted into bilirubin. Heme-derived Fe2+ induces the expression of the iron-sequestering protein ferritin and activates the ATPase Fe2+-secreting pump, which decrease intracellular free Fe2+ content. Based on the antioxidant effect of bilirubin and that of decreased free cellular Fe2+, we questioned whether HO-1 would modulate the expression of proinflammatory genes associated with endothelial cell (EC) activation. We tested this hypothesis specifically for the genes E-selectin (CD62), ICAM-1 (CD54), and VCAM-1 (CD106). We found that HO-1 overexpression in EC inhibited TNF-alpha-mediated E-selectin and VCAM-1, but not ICAM-1 expression, as tested at the RNA and protein level. Heme-driven HO-1 expression had similar effects to those of overexpressed HO-1. In addition, HO-1 inhibited the activation of NF-kappaB, a transcription factor required for TNF-alpha-mediated up-regulation of these genes in EC. Bilirubin and/or Fe2+ chelation mimicked the effects of HO-1, whereas biliverdin or carbon monoxide did not. In conclusion, HO-1 inhibits the expression of proinflammatory genes associated with EC activation via a mechanism that is associated with the inhibition of NF-kappaB activation. This effect of HO-1 is mediated by bilirubin and/or by a decrease of free intracellular Fe2+ but probably not by biliverdin or carbon monoxide.
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PMID:Heme oxygenase-1 modulates the expression of adhesion molecules associated with endothelial cell activation. 1500 56

Bilirubin is the end product of heme catabolism by heme oxygenases. The inducible form of these enzymes is heme oxygenase-1 (HO-1), which is the rate-limiting enzyme that can degrade heme into equimolar quantities of carbon monoxide (CO), biliverdin, and free iron. Biliverdin is very rapidly converted to bilirubin by the enzyme biliverdin reductase, and free iron upregulates the expression of ferritin. HO-1 is a ubiquitous stress protein and is induced in many cell types by various stimuli. Induced HO-1 exerts antiinflammatory effects and modulates apoptosis. Expression of HO-1 in vivo suppresses the inflammatory responses in endotoxic shock, hyperoxia, acute pleurisy, and organ transplantation, as well as ischemia-reperfusion injury, and thereby provides salutary effects in these conditions. Accumulating evidence indicates that biliverdin/bilirubin can mediate the protective effects of HO-1 in many disease models, such as IRI and organ transplantation, via its antiinflammatory, antiapoptotic, antiproliferative, and antioxidant properties, as well as its effects on the immune response. This review attempts to summarize these protective roles as well as the molecular mechanisms by which biliverdin/bilirubin benefit IRI and solid-organ transplantation, including chronic rejection, and islet transplantation.
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PMID:Therapeutic applications of bilirubin and biliverdin in transplantation. 1791 67

Mutations in hemochromatosis gene cause an inappropriately high absorption of iron that induces iron overload and deposition in several tissues, such as liver, pancreas, and heart. Iron overload in the liver has been associated with a high risk of hepatocarcinoma and susceptibility to viral and bacterial infections. The aim of this study was to describe the frequencies of HFE mutations among a kidney transplant population with versus without hepatitis C virus (HCV) infection, and its influence on liver and kidney status parameters. We selected 3 populations: 2 groups of kidney transplant recipients-59 with and 60 without HCV infection-and a third control group of 50 healthy subjects. We collected clinical data concerning liver and kidney status, such as iron, ferritin, albumin, creatinine, gamma GGT, GOT, proteinuria, %prothrombin, and Bilirubin. HFE mutations among patients and controls were determined by polymerase chain reaction-restriction fragment length polymorphism using DNA from the peripheral blood. We observed no significant difference with respect to the frequencies of HFE mutations between controls and patients with versus without HCV infection. Finally comparison of HFE positive versus negative mutation carriers in both groups suggest that any clinical parameter is associated with HFE mutations.
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PMID:Frequency and influence of hemochromatosis gene mutations in kidney transplant recipients with or without hepatitis C virus infection. 1971 39

Arterial thrombus formation is thought to be initiated by platelet adhesion to the subendothelial matrix, but ruptured atherosclerotic plaques are characterized by substantial reduction of matrix proteins compared with stable plaques. Intraplaque erythrocytes and/or fibrin have been reported in high-risk coronary plaques. The aims of the current study were to identify factors that provide scaffolds for platelets at the sites of ruptured coronary plaques and investigate depositions of iron and bilirubin as hemoglobin catabolites in the ruptured plaques. Histological characteristics of plaque components and the thrombus interface were examined in 73 acute coronary aspirated thrombi. Necrotic debris (95%), macrophages (95%), and cholesterin clefts (81%) were observed frequently at the ruptured plaque and thrombus interface. A fibrous matrix (47%), calcification (32%), and extracellular deoxyribonucleic acid (15%) were identified as small foci. Tissue factor was localized in the necrotic core and macrophages. Fibrin and von Willebrand factor were consistently deposited within the plaques and beneath platelet aggregations. The citrullinated histone H3-immunopositive area accounted for only 0.5% of the plaque area. Bilirubin and iron depositions were detected in approximately 20% of the plaques in addition to biliverdin reductase and ferritin expression in macrophages. Fibrin and von Willebrand factor rather than matrix proteins and neutrophil extracellular traps may be major adhesive molecules at the sites of ruptured plaques. Iron and bilirubin deposits may be markers for rupture-prone plaques.
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PMID:Pathological Features of Ruptured Coronary Plaque and Thrombus Interfaces: Fibrin and von Willebrand Factor as Platelet Scaffolds on Rupture Sites. 3292 Aug 6