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Query: UMLS:C0018801 (heart failure)
 72,216 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Transferrin receptor 2 (TfR2) is a type 2 transmembrane protein expressed in hepatocytes that binds iron-bound transferrin (Tf). Mutations in TfR2 cause one form of hereditary hemochromatosis, a disease in which excessive absorption of dietary iron can lead to liver cirrhosis, diabetes, arthritis, and heart failure. The function of TfR2 in iron homeostasis is unknown. We have studied the regulation of TfR2 in HepG2 cells. Western blot analysis shows that TfR2 increases in a time- and dose-dependent manner after diferric Tf is added to the culture medium. In cells exposed to diferric Tf, the amount of TfR2 returns to control levels within 8 hours after the removal of diferric Tf from the medium. However, TfR2 does not increase when non-Tf-bound iron (FeNTA) or apo Tf is added to the medium. The response to diferric Tf appears to be hepatocyte specific. Real-time quantitative reverse transcription-polymerase chain reaction (qRT-PCR) analysis shows that TfR2 mRNA levels do not change in cells exposed to diferric Tf. Rather, the increase in TfR2 is attributed to an increase in the half-life of TfR2 protein in cells exposed to diferric Tf. Our results support a role for TfR2 in monitoring iron levels by sensing changes in the concentration of diferric Tf.
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PMID:Diferric transferrin regulates transferrin receptor 2 protein stability. 1531 90

The anaemia of chronic kidney disease (CKD) is efficiently corrected with a combination of recombinant erythropoietin (rhEPO) and intravenous iron supplementation. Recently, patients with severe cardiac failure and anaemia have also been shown to benefit from this treatment. However, iron excess may lead to the production of free radicals and has been incriminated in the pathogenesis of atherosclerosis and increased risk of infection, the two major causes of death in end-stage renal disease. The exact risk of excess iron supplementation has not been defined and, in the absence of sensitive and specific indicators of iron overload, the risk remains difficult to quantify. There is increasing epidemiological evidence incriminating iron overload as a risk factor in CKD, but direct evidence is still hard to obtain. The precise role of iron is complicated further by the complex inter-relationships between iron metabolism and the inflammatory process characteristic of CKD. The recent discovery of the antimicrobial peptide, hepcidin, may shed light on these inter-relationships. New methods for quantifying non-transferrin-bound (or labile plasma) iron may help in the future to identify patients at risk for toxicity from excess iron supplementation.
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PMID:Intravenous iron supplementation in the anaemia of renal and cardiac failure--a double-edged sword? 1602 27

Cardiovacular disease is the main cause of morbidity and mortality in hemodialysis (HD) patients. However, there are no reliable data neither on the prevalence of cardiovacular disease nor its risk factors in Spain. The Morbidity and mortality Anemia Renal study (MAR) is a two-year multicenter, open-label, prospective cohorts study. Its main objective is to assess the general morbidity and mortality, particularly of a cardiovascular cause, and its relationship with the degree of anemia. Secondary objectives are: a/ the description of current clinical practices in anemia, dialysis, vascular access, and CV risk factor management; and b/ the description of hospitalization and mortality causes. This paper describes the prevalence of cardiovascular disease and risk factors of the HD population in Spain. A total of 1.710 patients were included (60% male, aged 64.4 years, 16.2 months on HD). The mean co-morbidity Charlson index was 6.5 +/- 2.3. Cardiovascular disease was the most prevalent comorbidity, 16.7% had a coronary disease, and 13.9% had different degrees of heart failure, while 11.6% had arrhythmia, 1.7% stroke and 5.5% peripheral artery disease. The prevalence of hypertension was 75.8%, 74.4% of patients received antihypertensive drugs, and still 40% of patients had an inadequate blood pressure control. The investigators considered as dyslipidemic 34.1% of patients, and prescribed treatment to 69.5% of them, while the remaining 30.5% (10.4% of the total) had hyperlipidemia with no drug therapy. Eleven percent was active smoker, and 26.6% former smoker. There was 47.4% of patients with a corporal mass index above 25. Secondary hyperparathyroidism with PTH above of 300 pg/ml was present in 22.2% of patients. Despite the EBPG and K-DOQI recommendations, only 68.8% of prevalent hemodialysis patients attained a hemoglobin (Hb) above 11 g/dl, 89.4% ferritin levels above 100 ng/ml, 66.5 degrees/a a transferrin saturation index (TSI) above 20%, and 61.1% met all three objectives. In summary, this first cross-sectional analysis has allowed us to know in detail the standard practice in multiple aspects of management of HD population in Spain. It has also established clear differences in the prevalence of cardiovascular disease and risk factors from the US registries. Last but not least we have identified therapeutic opportunities to improve the course and prognosis of our patients.
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PMID:[Cardiovascular risk in hemodialysis in Spain: prevalence, management and target results (MAR study)]. 1605 11

Juvenile haemochromatosis is an autosomal, recessive inherited iron metabolism disorder. The rapid deterioration and malignant prognosis differentiate juvenile haemochromatosis from hereditary haemochromatosis. The authors summarize the history of a 25 year old man, who worked in Hungary as a guest worker living in Romania. No significant illness has occurred in his previous history. The abdominal pain was his first symptom and he was treated in different institutions, where cholecystitis, alcoholic hepatic disease, hepatic cirrhosis were considered as a cause of his symptoms. Some weeks later atrial tachycardia, and congestive heart failure were observed and he was sent to our Cardiology Department. The echocardiography revealed diffuse hypokinesis, serious systolic dysfunction (ejection fraction: 21%), grade II mitral and tricuspid insufficiency with pulmonary hypertension. Considering the rapid deterioration of his cardiac function, myocarditis was suspected. Myocardial biopsy and coronary arteriography were performed. Coronary arteries were normal. Ventricular fibrillation occurred during coronary arteriography. Myocardial biopsy revealed juvenile haemochromatosis. Special laboratory examinations (transferrin saturation) were made after biopsy, that also confirmed the diagnosis of juvenile haemochromatosis. Cardiac transplantation was planned. Some days after the diagnosis was made the patient died of cardiogenic shock and intractable heart failure. Autopsy revealed hypogonadism and serious haemochromatosis in different parenchymal organs. Juvenile haemochromatosis should be considered in every young patient with congestive heart failure of unknown etiology.
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PMID:[Juvenile haemochromatosis presenting as intractable congestive heart failure]. 1646 15

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

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

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

The congenital disorders of glycosylation (CDG) are a recently described group of inherited multisystem disorders characterized by defects predominantly of N- and O-glycosylation of proteins. Cardiomyopathy in CDG has previously been described in several subtypes; it is usually associated with high morbidity and mortality and the majority of cases present in the first 2 years of life. This is the first case with presentation in late childhood and the article reviews current literature. An 11-year-old female with a background of learning difficulties presented in cardiac failure secondary to severe dilated cardiomyopathy. Prior to the diagnosis of CDG, her condition deteriorated; she required mechanical support (Excor Berlin Heart) and was listed for cardiac transplant. Investigations included screening for glycosylation disorders, and isoelectric focusing of transferrin revealed an abnormal type 1 pattern. Analysis of phosphomannomutase and phosphomannose isomerase showed normal enzyme activity, excluding PMM2 (CDG Ia) and MPI (CDG Ib). Lipid-linked oligosaccharide and mutational studies have not yet defined the defect. Despite aggressive therapy there were persistent difficulties achieving adequate anticoagulation and she developed multiple life-threatening thrombotic complications. She was removed from the transplant list and died from overwhelming sepsis 5 weeks following admission. This case emphasizes the need to screen all children with an undiagnosed cardiomyopathy for CDG, regardless of age, and where possible to exclude CDG before the use of cardiac bridging devices. It highlights the many practical and ethical challenges that may be encountered where clinical knowledge and experience are still evolving.
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PMID:Cardiomyopathy in the congenital disorders of glycosylation (CDG): a case of late presentation and literature review. 1975 45

Plasma BNP and NT-proBNP are often regarded as interchangeable parameters in assessing heart failure (HF) severity and prognosis. Renal failure results in disproportionate increases of NT-proBNP and an increased NT-proBNP/BNP ratio. Low kidney function is therefore considered particularly when NT-proBNP is used to assess HF. The purpose of this study was to identify other conditions affecting the NT-proBNP/BNP ratio. We examined the NT-proBNP/BNP ratio, 26 other lab parameters, and clinical factors in 218 patients admitted to the HF ward. In addition to renal function, we also found significant correlations between the NT-proBNP/BNP ratio and inflammation as measured by orosomucoid (r = 0.525, p < 0.0001), CRP (r = 0.333, p < 0.0001), haptoglobulin (r = 0.201, p = 0.02), and alpha1-antitrypsin (r = 0.223, p = 0.01). Reverse correlation was found with transferrin (r = -0.323, p < 0.0001), albumin (r = -0.251, p = 0.003), and S-Fe (r = -0.205, p = 0.02), parameters known to decrease during inflammation. Inflammation increased levels of NT-proBNP more than BNP, resulting in an increased NT-proBNP/BNP ratio. Our findings indicate that NT-proBNP should be evaluated concomitantly with inflammatory status to avoid overestimation of HF severity.
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PMID:Inflammation increases NT-proBNP and the NT-proBNP/BNP ratio. 2022 22

Underlying cardiovascular disease (CVD) is a risk factor for the exacerbation of air pollution health effects. Pulmonary oxidative stress, inflammation, and altered iron (Fe) homeostasis secondary to CVD may influence mammalian susceptibility to air pollutants. Rodent models of CVD are increasingly used to examine mechanisms of variation in susceptibility. Baseline cardiac and pulmonary disease was characterized in healthy normotensive Wistar Kyoto (WKY) rats, cardiovascular compromised spontaneously hypertensive rats (SHR), and spontaneously hypertensive heart failure (SHHF) rats. Blood pressure, heart rate, and breathing frequencies were measured in rats 11 to 12 wk of age, followed by necropsy at 14 to 15 wk of age. Blood pressure and heart rate were increased in SHR and SHHF relative to WKY rats (SHR > SHHF > WKY). Increased breathing frequency in SHHF and SHR (SHR > SHHF > WKY) resulted in greater minute volume relative to WKY. Bronchoalveolar lavage fluid (BALF) protein and neutrophils were higher in SHHF and SHR relative to WKY (SHHF >> SHR > WKY). Lung ascorbate and glutathione levels were low in SHHF rats. BALF Fe-binding capacity was decreased in SHHF relative to WKY rats and was associated with increased transferrin (Trf) and ferritin. However, lung ferritin was lower and Trf was higher in SHHF relative to WKY or SHR rats. mRNA for markers of inflammation and oxidative stress (macrophage inflammatory protein [MIP]-2, interleukin [IL]-1alpha, and heme oxygenase [HO]-1) were greater in SHHF and SHR relative to WKY rats. Trf mRNA rose in SHR but not SHHF relative to WKY rats, whereas transferrin receptors 1 and 2 mRNA was lower in SHHF rats. Four of 12 WKY rats exhibited cardiac hypertrophy despite normal blood pressure, while demonstrating some of the pulmonary complications noted earlier. This study demonstrates that SHHF rats display greater underlying pulmonary complications such as oxidative stress, inflammation, and impaired Fe homeostasis than WKY or SHR rats, which may play a role in SHHF rats' increased susceptibility to air pollution.
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PMID:Pulmonary oxidative stress, inflammation, and dysregulated iron homeostasis in rat models of cardiovascular disease. 2039 Nov 9


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