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)

Heme oxygenase (HO)-1 catabolizes heme into three products: carbon monoxide (CO), biliverdin (which is rapidly converted to bilirubin) and free iron (which leads to the induction of ferritin, an iron-binding protein). HO-1 serves as a "protective" gene by virtue of the anti-inflammatory, anti-apoptotic and anti-proliferative actions of one or more of these three products. Administration of CO, biliverdin, bilirubin or iron-binding compounds is protective in rodent disease models of ischemia-reperfusion injury, allograft and xenograft survival, intimal hyperplasia following balloon injury or as seen in chronic graft rejection and others. We suggest that the products of HO-1 action could be valuable therapeutic agents and speculate that HO-1 functions as a "therapeutic funnel", mediating the beneficial effects attributed to other molecules, such as interleukin-10 (IL-10), inducible nitric oxide synthase (NOS2; iNOS) and prostaglandins. This Review is the third in a series on the regulation of the immune system by metabolic pathways.
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PMID:Heme oxygenase-1: unleashing the protective properties of heme. 1290 59

Heme oxygenase-1 (HO-1) is a 32 kDa heat shock protein (HSP) that catalyzes heme to biliverdin, free iron and carbon monoxide in the brain. Furthermore, the release of free ferrous ion by HO-1 plays an essential role in ferritin synthesis, and ferritin stores iron either for intracellular utilization, or for detoxification. It is well known that HO-1 immunoreactivity is enhanced greatly in neurons and glia of the hippocampus and cerebral cortex in various pathophysiological conditions. The expression of HSP 70 is well known for the age-associated increase, but the expression modalities of HO-1 and ferritin associated with aging are still unknown. A study was therefore performed to examine the correlations in the expression of HO-1 and ferritin with age using immunohistochemistry. We investigated 31 autopsied brains (3-84-year-olds) without traumatic brain injury and neurodegenerative disease. The specimens were taken from the cerebral cortex and hippocampus. In the cerebral cortex, age (aging) had a statistically significant positive correlation with HO-1 (r=0.894, P<0.01) and ferritin (r=0.731, P<0.01). In the hippocampus, age had a significant positive correlation with only HO-1 (r=0.660, P<0.01). These results showed that HO-1 and ferritin underwent an age-related increase in human brain, especially in the cerebral cortex. Our results also indicate that various stress responses may persist in the aged human brain.
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PMID:Age-associated increases in heme oxygenase-1 and ferritin immunoreactivity in the autopsied brain. 1293 34

The iron storage protein, apoferritin, has a cavity in which iron is oxidized and stored as a hydrated oxide core. The size of the core is about 7 nm in diameter and is regulated by the cavity size. The cavity can be utilized as a nanoreactor to grow inorganic crystals. We incubated apoferritin in nickel or chromium salt solutions to fabricate hydroxide nanoparticles in the cavity. By using a solution containing dissolved carbon dioxide and by precisely controlling the pH, we succeeded in fabricating nickel and chromium cores. During the hydroxylation process of nickel ions a large portion of the apoferritin precipitated through bulk precipitation of nickel hydroxide. Bulk precipitation was suppressed by adding ammonium ions. However, even in the presence of ammonium ions the core did not form using a degassed solution. We concluded that carbonate ions were indispensable for core formation and that the ammonium ions prevented precipitation in the bulk solution. The optimized condition for nickel core formation was 0.3 mg/mL horse spleen apoferritin and 5 mM ammonium nickel sulfate in water containing dissolved carbon dioxide. The pH was maintained at 8.65 using two buffer solutions: 150 mM HEPES (pH 7.5) and 195 mM CAPSO (pH 9.5) with 20 mM ammonium at 23 degrees C. The pH had not changed after 48 h. After 24 h of incubation, all apoferritins remained in the supernatant and all of them had cores. Recombinant L-ferritin showed less precipitation even above a pH of 8.65. A chromium core was formed under the following conditions: 0.1 mg/mL apoferritin, 1 mM ammonium chromium sulfate, 100 mM HEPES (pH 7.5) with a solution containing dissolved carbon dioxide. About 80% of the supernatant apoferritin (0.07 mg/mL) formed a core. In nickel and chromium core formation, carbonate ions would play an important role in accelerating the hydroxylation in the apoferritin cavity compared to the bulk solution outside.
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PMID:Fabrication of nickel and chromium nanoparticles using the protein cage of apoferritin. 1296 75

Heme oxygenase-1 (HO-1), a stress-responsive enzyme that catabolizes heme into carbon monoxide (CO), biliverdin, and iron, has previously been shown to protect grafts from ischemia/reperfusion injury and rejection. Here we investigated the protective potential of HO-1 in 5 models of immune-mediated liver injury. We found that up-regulation of endogenous HO-1 by cobalt-protoporphyrin-IX (CoPP) protected mice from apoptotic liver damage induced by anti-CD95 antibody (Ab) or d-galactosamine in combination with either anti-CD3 Ab, lipopolysaccharide (LPS), or tumor necrosis factor alpha (TNF-alpha). HO-1 induction prevented apoptotic liver injury, measured by inhibition of caspase 3 activation, although it did not protect mice from caspase-3-independent necrotic liver damage caused by concanavalin A (Con A) administration. In addition, overexpression of HO-1 by adenoviral gene transfer resulted in protection from apoptotic liver injury, whereas inhibition of HO-1 enzymatic activity by tin-protoporphyrin-IX (SnPP) abrogated the protective effect. HO-1-mediated protection seems to target parenchymal liver cells directly because CoPP treatment protected isolated primary hepatocytes from anti-CD95-induced apoptosis in vitro. Furthermore, depletion of Kupffer cells (KCs) did not interfere with the protective effect in vivo. Exogenous CO administration or treatment with the CO-releasing agent methylene chloride mimicked the protective effect of HO-1, whereas treatment with exogenous biliverdin or overexpression of ferritin by recombinant adenoviral gene transfer did not. In conclusion, HO-1 is a potent protective factor for cytokine- and CD95-mediated apoptotic liver damage. Induction of HO-1 might be of a therapeutic modality for inflammatory liver diseases.
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PMID:Heme oxygenase-1 and its reaction product, carbon monoxide, prevent inflammation-related apoptotic liver damage in mice. 1572 11

Heme oxygenase (HO) is a cytoprotective enzyme that degrades heme (a potent oxidant) to generate carbon monoxide (a vasodilatory gas that has anti-inflammatory properties), bilirubin (an antioxidant derived from biliverdin), and iron (sequestered by ferritin). Due to the properties of inducible HO (HO-1) and its products, we hypothesized that HO-1 would play an important role in the regulation of cardiovascular function. In this article we will review the role of HO-1 in cardiovascular function, and highlight our previous studies using gene deletion and gene overexpression transgenic approaches in mice. These studies will include the investigation of HO-1 in the setting of hypertension (renovascular), atherosclerosis and vascular injury (vein graft stenosis), hypotension (endotoxemia), and ischemia/reperfusion injury (heart). In a chronic renovascular hypertension model, blood pressure elevation, cardiac hypertrophy, acute renal failure, and acute mortality induced by one kidney-one clip surgery are more severe in HO-1 null mice. Moreover, absence of HO-1 leads to accelerated atherosclerotic lesion formation and vein graft disease. In addition, HO-1 null mice with endotoxemia have earlier resolution of hypotension, yet the mortality and the incidence of end organ damage are higher in the absence of HO-1. In contrast, mice with cardiac-specific overexpression of HO-1 have an improvement in cardiac function, smaller myocardial infarcts, and reduced inflammatory and oxidative damage after coronary artery ligation and reperfusion. Taken together, these studies suggest that an absence of HO-1 has detrimental consequences, while overexpression of HO-1 plays a protective role in ischemia/reperfusion injury.
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PMID:Role of heme oxygenase-1 in cardiovascular function. 1452 47

Heme oxygenase (HO), an enzyme essential for heme degradation, shows anti-oxidative and anti-inflammatory properties via the production of bile pigments, carbon monoxide (CO) and ferritin induction under various pathophysiological conditions. A number of recent studies have shown biological effects of HO reaction in cardiovascular disorders. An inducible form of HO, HO-1, is induced by a variety of stresses such as oxidized lipoproteins, cytokines, hemodynamic changes, angiotensin II and nitric oxide (NO) in vascular wall. HO-1 induction seems to function as an adaptive response against these injurious stimuli. HO-1 induction in artery wall scavenges reactive oxygen species, which leads to the attenuation of monocyte adhesion and chemotaxis. HO-1 induction also reduces lipid peroxidation in plasma and artery wall. These properties of HO-1 suggest anti-atherogenic roles of this enzyme. In this review, roles of endothelial HO-1 expression and bilirubin in atherogenesis are also discussed. HO-1 also seems to play a significant role in restenosis after angioplasty, which is a major clinical problem associated with atherosclerosis. Recent progress in human HO-1 genetics supports these experimental results. This review aims to reaffirm current problems in the biological aspects of HO and suggest future research direction and clinical application.
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PMID:Heme oxygenase-1 against vascular insufficiency: roles of atherosclerotic disorders. 1452 48

Heme oxygenase-1 (HO-1) and p21 influence cell fate, and genetic HO-1 overexpression upregulates p21 and confers resistance to apoptosis. The present study examined the effects of heme, a metabolite incriminated in renal injury, on sensitivity to apoptosis and cell growth in conjunction with cellular expression of HO-1 and p21. Immortalized rat proximal tubular epithelial cells (IRPTCs) were exposed to hemin (10 microM) in serum-deplete media (0.1% FBS) and in standard cell culture media (5.0% FBS). In the presence of 0.1% FBS media, hemin induced p21 through an HO-dependent, p53-independent mechanism; certain products of HO activity (iron and carbon monoxide), but not others (ferritin, apoferritin, bilirubin), recapitulated these inductive effects on p21 expression. Along with this inductive effect on HO-1 and p21, hemin worsened apoptosis, the latter exacerbated by the inhibition of HO activity and loss of p21 expression. In IRPTCs maintained in 5% FBS, hemin induced HO-dependent p21 expression, provoked cell cycle arrest, and inhibited cell growth without inducing apoptosis; this inhibitory effect of hemin on cell growth was blocked by the concomitant inhibition of HO activity and loss of p21 expression. We conclude that hemin is a potent HO-dependent inducer of p21 and that hemin increases the sensitivity to apoptosis in serum-deplete conditions and decreases cell growth in serum-replete conditions; inhibiting HO activity and concomitantly ablating p21 expression exacerbate apoptosis and reverse the growth-inhibitory actions of hemin. We suggest that these effects of heme may influence the nature of, and recovery from, ischemic and nephrotoxic insults to the kidney.
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PMID:Heme: a determinant of life and death in renal tubular epithelial cells. 1470 7

The genes for heat shock proteins (Hsps) can be upregulated in response to cellular trauma, resulting in enhanced cell survival and protection. Hsp32, also known as heme oxygenase 1, catalyzes the degradation of heme to produce carbon monoxide and bilirubin, which play a variety of cytoprotective functions at physiological concentrations, and iron, which is rapidly sequestered by the iron-binding protein ferritin. In the present study we examined the expression and localization of Hsp32 in the rat cochlea after heat shock using semi-quantitative reverse transcription polymerase chain reaction (RT-PCR), Western blot, and immunocytochemistry. Low levels of constitutive Hsp32 expression were observed in the normal rat cochlea by RT-PCR and Western blot. Hsp32 mRNA (messenger RNA) was present at higher levels in a subfraction containing sensorineural epithelium and lateral wall than in a subfraction containing modiolus. Western blot revealed that Hsp32 protein levels increase in the rat cochlea following heat shock. Immunocytochemistry showed scattered staining of outer hair cells in the organ of Corti of normal untreated rats. Following heat shock Hsp32 is upregulated in outer hair cells and the cells of the stria vascularis. These results suggest a potential role for Hsp32 as a component of the oxidative stress response pathway in the rat cochlea.
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PMID:Induction of heat shock protein 32 (Hsp32) in the rat cochlea following hyperthermia. 1475 65

Nitric acid esters such as glyceryl trinitrate were introduced into therapy more than a century ago and are still widely used for the treatment of myocardial ischemia and its main symptom angina pectoris. The basic mechanisms responsible for the vasodilatory and anti-ischemic action of organic nitrates involve bioactivation of, and nitric oxide (NO) release from, these compounds which have therefore been termed NO donors. The organic nitrate pentaerythritol tetranitrate (PETN) is known to possess antioxidant properties that are thought to be the underlying cause for its specific pharmacological profile. In contrast to other long-acting nitrates, PETN induces tolerance- free vasodilation in humans and was reported to prevent endothelial dysfunction as well as atherogenesis in cholesterol- fed rabbits. However, the exact nature of the vasoprotective signaling pathways triggered by PETN has remained obscure. The present study demonstrates that the active PETN metabolite PETriN stimulates protein expression of the antioxidant defense protein heme oxygenase-1 (HO-1; Figures 1 and 2). Additionally, PETriN enhanced the enzymatic activity of HO-1 measured as formation of the HO-1 metabolites bilirubin (Figure 3) and carbon monoxide (Figure 4) in lysates from endothelial cells. HO-1 induction subsequently led to a marked increase in protein expression of a second antioxidant protein, ferritin, via the HO-1-dependent release of free iron from endogenous heme sources (Figures 1 and 5). Pretreatment of endothelial cells with PETriN was followed by increased cellular resistance to oxidant injury mediated by hydrogen peroxide (Figure 6). Endothelial protection by PETriN was mimicked by exogenous bilirubin which led to an almost complete reversal of hydrogen peroxide-induced toxicity (Figure 8). Increased HO-1 and ferritin expression as well as endothelial protection occurred at micromolar concentrations of PETriN which are well within the range of plasma or tissue levels that can be expected during oral therapy. The capacity to protect the endothelium in vitro may translate into and explain the previously observed antiatherogenic actions of PETN in vivo. In this study, another long-acting nitrate, isosorbide dinitrate (ISDN), did not protect endothelial cells from oxidant damage (Figure 6). The absence of significant cytoprotection in the presence of ISDN was paralleled by a lack of HO-1 and ferritin stimulatory capacity (Figures 2 and 5). ISDN had no significant effect on carbon monoxide release or bilirubin formation (Figures 3 and 4). These observations are in agreement with results demonstrating small or nondetectable amounts of NO released from ISDN and its active metabolite isosorbide mononitrate (ISMN) measured as cyclic GMP formation in RFL-6 reporter cells (Figure 7). Interestingly and in contrast to PETN, isosorbide nitrates are known to induce tolerance to their cardiovascular effects, presumably via oxidant stress. Moreover, in earlier investigations aimed at assessing the antiatherogenic potential of nitrates, PETN but not isosorbide nitrates prevented plaque formation and endothelial dysfunction in animal models of atherosclerosis. Thus, the ability to activate HO-1 induction and associated antioxidant pathways apparently distinguishes PETN from other long-acting nitrates and may explain their different patterns of action in vivo (Figure 9).
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PMID:[Therapy with NO donors-antiatherogenic and antioxidant actions]. 1496 47

Carbon monoxide (CO), a product of organic oxidation processes, arises in vivo during cellular metabolism, most notably heme degradation. CO binds to the heme iron of most hemoproteins. Tissue hypoxia following hemoglobin saturation represents a principle cause of CO-induced mortality in higher organisms, though cellular targets cannot be excluded. Despite extreme toxicity at high concentrations, low concentrations of CO can confer cytoprotection during ischemia/reperfusion or inflammation-induced tissue injury. Likewise, heme oxygenase, an enzyme that produces CO, biliverdin and iron, as well as a secondary increase in ferritin synthesis, from the oxidation of heme, can confer protection in vivo and in vitro. CO has been shown to affect several intracellular signaling pathways, including guanylate cyclase, which generates guanosine 3':5' cyclic monophosphate and the mitogen-activated protein kinases (MAPK). Such pathways mediate, in part, the known vasoregulatory, anti-inflammatory, anti-apoptotic and anti-proliferative effects of this gas. Exogenous CO delivered at low concentrations is showing therapeutic potential as an anti-inflammatory agent and as such can modulate numerous pathophysiological states. This review will delve into the biological significance and medical applications of this gas molecule.
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PMID:Carbon monoxide in biology and medicine. 1498 28


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