Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0018801 (heart failure)
 72,216 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In thalassemia, deficient globin-chain production during erythropoiesis results in anemia. Thalassemia may be further complicated by iron overload (frequently exacerbated by blood transfusion), which induces numerous endocrine diseases, hepatic cirrhosis, cardiac failure and even death. Accumulation of iron in the absence of blood transfusions may result from inappropriate suppression of the iron-regulating peptide hepcidin by an erythropoietic mechanism. To test this hypothesis, we examined erythroblast transcriptome profiles from 15 healthy, nonthalassemic donors. Growth differentiation factor 15 (GDF15), a member of the transforming growth factor-beta superfamily, showed increased expression and secretion during erythroblast maturation. Healthy volunteers had mean GDF15 serum concentrations of 450 +/- 50 pg/ml. In comparison, individuals with beta-thalassemia syndromes had elevated GDF15 serum levels (mean 66,000 +/- 9,600 pg/ml; range 4,800-248,000 pg/ml; P < 0.05) that were positively correlated with the levels of soluble transferrin receptor, erythropoietin and ferritin. Serum from thalassemia patients suppressed hepcidin mRNA expression in primary human hepatocytes, and depletion of GDF15 reversed hepcidin suppression. These results suggest that GDF15 overexpression arising from an expanded erythroid compartment contributes to iron overload in thalassemia syndromes by inhibiting hepcidin expression.
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PMID:High levels of GDF15 in thalassemia suppress expression of the iron regulatory protein hepcidin. 1782 18

There are few descriptions of young adults with self-reported hemochromatosis or iron overload (H/IO). We analyzed initial screening data in 7,343 HEmochromatosis and IRon Overload Screening (HEIRS) Study participants ages 25-29 years, including race/ethnicity and health information; transferrin saturation (TS) and ferritin (SF) measurements; and HFE C282Y and H63D genotypes. We used denaturing high-pressure liquid chromatography and sequencing to detect mutations in HJV, TFR2, HAMP, SLC40A1, and FTL. Fifty-one participants reported previous H/IO; 23 (45%) reported medical conditions associated with H/IO. Prevalences of reports of arthritis, diabetes, liver disease or liver cancer, heart failure, fertility problems or impotence, and blood relatives with H/IO were significantly greater in participants with previous H/IO reports than in those without. Only 7.8% of the 51 participants with previous H/IO reports had elevated TS; 13.7% had elevated SF. Only one participant had C282Y homozygosity. Three participants aged 25-29 years were heterozygous for potentially deleterious mutations in HFE2, TFR2, and HAMP promoter, respectively. Prevalences of self-reported conditions, screening iron phenotypes, and C282Y homozygosity were similar in 1,165 participants aged 30 years or greater who reported previous H/IO. We conclude that persons who report previous H/IO diagnoses in screening programs are unlikely to have H/IO phenotypes or genotypes. Previous H/IO reports in some participants could be explained by treatment that induced iron depletion before initial screening, misdiagnosis, or participant misunderstanding of their physician or the initial screening questionnaire.
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PMID:Characteristics of participants with self-reported hemochromatosis or iron overload at HEIRS study initial screening. 1772 83

A 28-year was admitted with heart failure. His medical history included treatment for hypogonadotropic hypogonadism. Echocardiography showed dilatation of all chambers. Elevated serum ferritin levels and liver biopsy indicated hereditary hemochromatosis. Cardiac iron overload was seen on magnetic resonance imaging. Genetic testing revealed homozygosis for G320 V mutation, confirming the diagnosis of juvenile hemochromatosis. Phlebotomy on a biweekly regimen was started and after twelve months of therapy the patient had normal ferritin values as well as normal ejection fraction on echocardiography.
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PMID:[28-year old patient with successfully treated dilatative cardiomyopathy]. 1821 19

Cardiac damage caused by iron overload toxicity is the main cause of death in thalassemia patients. Biopsy samples of poorly chelated thalassemia patients who suffered congestive cardiac failure (CCF) show extensive iron deposition in the myocardium. In one patient who survived CCF, a cardiac biopsy was performed during the removal of a thrombus caused by a port-a-cath, which was used for the administration of intravenous (iv) deferoxamine (DFO). Ultrastructural pathology studies of the cardiac biopsy indicated extensive iron deposition in myocytes with accumulation of iron mainly in lysosomes, leading in some cases to their disruption. Damage to other intracellular components of the myocytes and loss of myofibers was also observed. The patient became intolerant to iv and subcutaneous (sc) DFO 2 years after the CCF, and was then treated with deferiprone (L1) for 7 years. Within 1 year of L1 treatment at 75-80 mg/kg/day, serum ferritin levels were reduced to <0.45 mg/L and she became asymptomatic, needing no further drugs for her cardiomyopathy. Lowering the L1 dose to 50-70 mg/kg/day caused an increase in serum ferritin levels. Maintenance of normal iron stores during the last 3 years as detected by cardiac and liver magnetic resonance imaging (MRI) T2 and T2* and normalization of serum ferritin levels (<0.15 mg/L) was observed following L1 therapy at 80-85 mg/kg/day. Deferiprone (>80 mg/kg/day) appears to be effective in the rapid clearance of cardiac iron, in the reversal of iron overload related cardiomyopathy, in the maintenance of normal iron stores and the overall long-term survival of thalassemia patients.
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PMID:Myocyte damage and loss of myofibers is the potential mechanism of iron overload toxicity in congestive cardiac failure in thalassemia. Complete reversal of the cardiomyopathy and normalization of iron load by deferiprone. 1827 79

The biology of iron in relation to anemia is best understood by a review of the iron cycle, since the majority of iron for erythropoiesis is provided by iron recovered from senescent erythrocytes. In iron-deficiency anemia, storage iron declines until iron delivery to the bone marrow is insufficient for erythropoiesis. This can be monitored with clinical indicators, beginning with low plasma ferritin, followed by decreased plasma iron and transferrin saturation, and culminating in red blood cells with low-Hb content. When adequate dietary iron is provided, these markers show return to normal, indicating a response to the dietary supplement. Anemia of inflammation (also known as anemia of chronic disease, or ACD) follows a different course, because in this form of anemia storage iron is often abundant but not available for erythropoiesis. The diagnosis of ACD is more difficult than the diagnosis of iron-deficiency anemia, and often the first identified symptom is the failure to show a response to a dietary iron supplement. Confirmation of ACD is best obtained from elevated markers of inflammation. The treatment of ACD, which typically employs erythropoietin (EPO) supplements and intravenous iron (i.v.-iron), is empirical and often falls shorts of therapeutic goals. Dialysis patients show a complex pattern of anemia, which results from inadequate EPO production by the kidney, inflammation, changes in nutrition, and blood losses during treatment. EPO and i.v.-iron are the mainstays of treatment. Patients with heart failure can be anemic, with incidence as high as 50%. The causes are multifactorial; inflammation now appears to be the primary cause of this form of anemia, with contributions from increased plasma volume, effects of drug therapy, and other complications of heart disease. Discerning the mechanisms of anemia for the heart failure patient may aid rational therapy in each case.
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PMID:Iron and anemia in human biology: a review of mechanisms. 1836 95

Heart failure due to myocardial iron overload remains the leading cause of death in patients with transfusion-dependent anemias. Iron overload-induced cardiomyopathy is reversible if intensive chelation therapy is instituted on time. Thus, early detection of myocardial iron deposition is imperative to prevent overt heart failure. Conventional cardiac monitoring, including physical examination, electrocardiography, echocardiography or serum ferritin levels fail to predict manifest or subclinical myocardial involvement resulting from iron overload. Cardiovascular magnetic resonance imaging T2* (cMRI-T2*, pronounced T2 star) times correlate well with myocardial iron levels. This timely review focuses on the utility of cMRI-T2*, for the preclinical detection of myocardial iron overload and monitoring of myocardial iron content during chelation therapy.
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PMID:Quantification of myocardial iron overload by cardiovascular magnetic resonance imaging T2* and review of the literature. 1841 44

We performed MRI and endocrine assessment in 27 adult Chinese patients with severe aplastic anemia (SAA) and myelodysplasia (MDS). Despite high ferritin levels, cardiac hemosiderosis and heart failure was not common, and were not concordant in most cases. However, significant correlation was found between cardiac T2/T2* MRI assessment, ejection fraction and ferritin levels. Furthermore, there was a high incidence subclinical pancreatic abnormality that was related to liver MRI T2* readings. Hence, chelating agents may still have a role to improve organ function. Prospective data with serial functional and imaging monitoring is needed.
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PMID:A pilot MRI study of organ specific hemosiderosis and functional correlation in Chinese patients with myelodysplasia and aplastic anemia with raised ferritin levels. 1848 75

Recent studies have raised questions about the long-term health risks for individuals with mutations in the HFE gene, although previous studies may have been plagued by selection bias or lack of population-based comparison groups. We examined cardiovascular disease risk factors and iron and liver biomarkers, as well as morbidity and mortality associated with the C282Y and H63D variants of HFE in the Atherosclerosis Risk in Communities (ARIC) study, which is a population-based cohort of nearly 16,000 U.S. white and black men and women who were 45-64 years old at baseline. Subjects were followed for an average of 15 years for death, incident coronary heart disease, stroke, and heart failure, and an average of 8 years for incident diabetes. The prevalence of C282Y homozygosity was 0.42% (45/10,800) in whites, which is similar to other North American population-based studies. C282Y homozygotes had significantly lower mean low-density lipoprotein (LDL) cholesterol and fibrinogen as well as higher mean levels of iron (ferritin, transferrin saturation) and liver biomarkers (alanine aminotransferase, Hepascore) compared with HFE wild-type subjects. Rates of all-cause mortality, cardiovascular disease, and diabetes were similar across HFE genotypes. These prospective, population-based data indicate higher serum iron indices and possible mild liver dysfunction or disease in some C282Y homozygotes, but they provide little evidence that HFE C282Y or H63D mutations are related to all-cause mortality, cardiovascular disease, or diabetes. Reduced LDL in C282Y homozygotes may be because of effects of excess iron on cholesterol metabolism and lipoprotein formation in the liver.
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PMID:HFE C282Y homozygotes have reduced low-density lipoprotein cholesterol: the Atherosclerosis Risk in Communities (ARIC) Study. 1859 31

Ferritin heavy chain (FHC) protein was significantly reduced in murine failing hearts following left coronary ligation or thoracic transverse aortic constriction. The mRNA expression of FHC was not significantly altered in failing hearts, compared to that in control sham-operated hearts. Prussian blue staining revealed spotty iron depositions in myocardial infarct failing hearts. Oxidative stress was enhanced in the myocardial infarct failing hearts, as evidenced by increases in 4-hydroxy-2-nonenal and 8-hydroxy-2'-deoxyguanosine immunoreactivity. To clarify the functional significance of FHC downregulation in hearts, we infected rat neonatal cardiomyocytes with adenoviral vector expressing short hairpin RNA targeted to FHC (Ad-FHC-RNAi). The downregulation of FHC induced a reduction in the viability of cardiomyocytes. The relative number of iron deposition-, 4-hydroxy-2-nonenal- or 8-hydroxy-2'-deoxyguanosine-positive cardiomyocytes was significantly higher in Ad-FHC-RNAi-infected cardiomyocytes than in control vector-infected cardiomyocytes. Treatment of Ad-FHC-RNAi-infected cardiomyocytes with desferrioxamine, an iron chelator, significantly reduced the number of iron, 4-hydroxy-2-nonenal or 8-hydroxy-2'-deoxyguanosine-positive cells, and increased viability. In addition, treatment with N-acetyl cysteine, an antioxidant, significantly reduced the number of 4-hydroxy-2-nonenal- or 8-hydroxy-2'-deoxyguanosine-positive cells. Reduced viability in Ad-FHC-RNAi-infected cardiomyocytes was significantly improved with N-acetyl cysteine treatment. These findings indicate that excessive free iron and the resultant enhanced oxidative stress caused by downregulation of FHC lead to cardiomyocyte death. The decrease in FHC expression in failing hearts may play an important role in the pathogenesis of heart failure.
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PMID:Downregulation of ferritin heavy chain increases labile iron pool, oxidative stress and cell death in cardiomyocytes. 1899 54

beta-Thalassemia major is a debilitating disease with a considerable incidence in Lebanon (around 2-3% carriership). The present article describes our experience to this day with 214 patients, emphasizing the survival of beta-thalassemia major and development of complications among patients with different parameters. Fifteen deaths were reported. The most common cause of death was heart failure (60%). Patients with a ferritin level of 3,000 ng/ml showed better survival than those with a level >3,000 ng/ml (p < 0.006). In addition, patients with a ferritin level of 1,500 ng/ml showed less complication-free survival than those with a level >1,500 ng/ml (p < 0.024). High level of ferritin (1,500 ng/ml) is associated with increased risk of heart failure. Overall and complication-free survival were statistically different among patients classified according to birth cohort or ferritin level. The Chronic Care Center, a multidisciplinary center located in the suburbs of Beirut, led to an increase in complication-free as well as overall survival. Although patients are being diagnosed earlier and chelation therapy is being initiated at an earlier age, complications due to iron overload still persist. The introduction of new oral iron chelators and better iron overload quantitation methods will most likely modify this picture, and a follow-up study will examine their impact.
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PMID:Survival and complications of beta-thalassemia in Lebanon: a decade's experience of centralized care. 1900 6


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