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)

Moderate hyperhomocysteinemia (HHCY) is a risk factor for cardiovascular (CVD) and neurodegenerative diseases, osteoporotic fractures and complications during pregnancy. Elderly persons have a high prevalence of HHCY. Vitamin deficiency is by far the most common cause of HHCY. Retrospective and prospective studies emphasize a causal relationship between HHCY and the CVD risk. Some vitamin intervention trials, however, did not lower the risk of CVD. From power calculation one can conclude that these trials may not involve sufficient numbers of patients to assure statistically valid conclusions. Re-analysis of the VISP study (excluding renal failure and vitamin B12 status tampering factors), however, detected a 21% decrease in the risk of stroke. This number has been confirmed by results from the HOPE 2 vitamin intervention trial. Folic acid enrichment of grain products in the US and Canada has led to a significant decline of stroke mortality, since 1998 annually 12900 fewer stroke deaths in the US and 2800 fewer stroke deaths in Canada. Despite negative results from secondary prevention trials regarding the CVD risk reduction there is convincing evidence about the effectiveness of B-vitamin supplementation in lowering the stroke risk. The overall decline in stroke risk calculated in meta-analysis from prospective studies and found in intervention trials is around 20%. Additionally, HHCY was recently linked to the occurrence and severity of chronic heart failure. HHCY is also a risk factor for osteoporotic fractures and vitamin treatment lowered the fracture risk significantly. Furthermore, there is a correlation between HHCY and cognitive disorders or Alzheimer's disease. HHCY is a predictive parameter for the decline in cognitive function. Hypomethylation is among the central mechanisms through which HHCY acts cytotoxically. HHCY and low folate are causal factors for pregnancy complications. In addition to the recommended folate supplementation, vitamin B12 supplementation could further decrease pregnancy complications. Determination of homocysteine plasma concentration should be part of the individual risk profile, especially for elderly subjects who are at risk for CVD, neurodegenerative diseases or osteoporotic fractures.
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PMID:Significance of hyperhomocysteinemia. 1695 35

Endothelium has many important functions including the control of blood-tissue permeability and vascular tonus, regulation of vascular surface properties for homeostasis and inflammation. Nitric oxide is the chief molecule in regulation of endothelial functions. Nitric oxide deficiency, which is also known as endothelial dysfunction, is the first step for the occurrence of many disease states in cardiovascular system including heart failure, hypertension, dyslipidemia, insulin resistance, diabetes mellitus, hyperhomocysteinemia and smoking. This review deals with the importance of nitric oxide for cardiovascular system. It also includes the latest improvements in the diagnosis and treatment of endothelial dysfunction.
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PMID:Nitric oxide and cardiovascular system. 1716 86

Elevated levels of homocysteine (Hcy) known as hyperhomocysteinemia (HHcy) are associated with arrhythmogenesis and sudden cardiac death (SCD). Hcy decreases constitutive neuronal and endothelial nitric oxide (NO), and cardiac diastolic relaxation. Hcy increases the iNOS/NO, peroxynitrite, mitochondrial NADPH oxidase, and suppresses superoxide dismutase (SOD) and redoxins. Hcy activates matrix metalloproteinase (MMP), disrupts connexin-43 and increases collagen/elastin ratio. The disruption of connexin-43 and accumulation of collagen (fibrosis) disrupt the normal pattern of cardiac conduction and attenuate NO transport from endothelium to myocyte (E-M) causing E-M uncoupling, leading to a pro-arrhythmic environment. The goal of this review is to elaborate the mechanism of Hcy-mediated iNOS/NO in E-M uncoupling and SCD. It is known that Hcy creates arrhythmogenic substrates (i.e. increase in collagen/elastin ratio and disruption in connexin-43) and exacerbates heart failure during chronic volume overload. Also, Hcy behaves as an agonist to N-methyl-D-aspartate (NMDA, an excitatory neurotransmitter) receptor-1, and blockade of NMDA-R1 reduces the increase in heart rate-evoked by NMDA-analog and reduces SCD. This review suggest that Hcy increases iNOS/NO, superoxide, metalloproteinase activity, and disrupts connexin-43, exacerbates endothelial-myocyte uncoupling and cardiac failure secondary to inducing NMDA-R1.
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PMID:Arrhythmia and neuronal/endothelial myocyte uncoupling in hyperhomocysteinemia. 1717 94

Glucose-mediated impairment of homocysteine (Hcy) metabolism and decrease in renal clearance contribute to hyperhomocysteinemia (HHcy) in diabetes. The Hcy induces oxidative stress, inversely relates to the expression of peroxisome proliferators activated receptor (PPAR), and contributes to diabetic complications. Extracellular matrix (ECM) functionally links the endothelium to the myocyte and is important for cardiac synchronization. However, in diabetes and hyperhomocysteinemia, a "disconnection" is caused by activated matrix metalloproteinase with subsequent accumulation of oxidized matrix (fibrosis) between the endothelium and myocyte (E-M). This contributes to "endothelial-myocyte uncoupling," attenuation of cardiac synchrony, leading to diastolic heart failure (DHF), and cardiac dys-synchronizatrion. The decreased levels of thioredoxin and peroxiredoxin and cardiac tissue inhibitor of metalloproteinase are in response to antagonizing PPARgamma.
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PMID:Cardiac synchronous and dys-synchronous remodeling in diabetes mellitus. 1750 18

Chronic volume/pressure overload-induced heart failure augments oxidative stress and activates matrix metalloproteinase which causes endocardial endothelial-myocyte (EM) uncoupling eventually leading to decline in myocardial systolic and diastolic function. The elevated levels of homocysteine (Hcy), hyperhomocysteinemia (HHcy), are associated with decline in cardiac performance. Hcy impairs the EM functions associated with the induction of ventricular hypertrophy leading to cardiac stiffness and diastolic heart failure. Hcy-induced neurological defects are mediated by the NMDA-R (N-methyl-D-aspartate (NMDA) receptor) activation. NMDA-R is expressed in the heart. However, the role of NMDA-R on cardiac function during HHcy is still in its infancy. The blockade of NMDA-R attenuates NMDA-agonist-induced increase in the heart rate. Hcy increases intracellular calcium and activates calpain and calpain-associated mitochondrial (mt) abnormalities have been identified in HHcy. Mitochondrial permeabilization and uncoupling in the pathological setting is fueled by redox stress and calcium mishandling. Recently the role of cyclophilin D, a component of the mitochondrial membrane permeability transition pore, has been identified in cardiac-ischemia. Mechanisms underlying the potentiation between NMDA-R activation and mitochondrial defects leading to cardiac dysfunction during HHcy remain to be elucidated. This review addresses the mitochondrial mechanism by which Hcy contributes to the decline in mechano-electrical function and arrhythmogenesis via agonizing NMDA-R. The putative role of mitochondrial MMP activation, protease stress and mitochondrial permeability transition in cardiac conduction during HHcy is discussed. The review suggests that Hcy increases calcium overload and oxidative stress in the mitochondria and amplifies the activation of mtMMP, causing the opening of mitochondrial permeability transition pore leading to mechano-electrical dysfunction.
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PMID:Mitochondrial MMP activation, dysfunction and arrhythmogenesis in hyperhomocysteinemia. 1839 9

TREATMENT OF ARTERIAL HYPERTENSION - Blood pressure (BP) should be regularly measured in all patients with CKD (Strength of Recommendation C). - BP control and proteinuria reduction delay progression of CKD (Strength of Recommendation A) and reduce cardiovascular risk (Strength of Recommendation C). Thus, control of both factors should be the treatment objective. - The BP target in patients with CKD should be < 130/80 mmHg, and 125/75 mmHg if proteinuria is > 1 g/24 hours (Strength of Recommendation A). - Lifestyle changes should be made: low-sodium diet (less than 100 mEq/day of sodium or 2.4 g/day of salt); weight reduction if patient is overweight (body mass index 20-25 kg/m2); regular aerobic physical exercise and moderate alcohol intake for BP control and prevention of cardiovascular risk (Strength of Recommendation A). - The choice of the antihypertensive drug in patients with CKD depends on the etiology of CKD, cardiovascular risk, or presence of clinical or subclinical cardiovascular disease (Strength of Recommendation A). - Two or more antihypertensive drugs are usually required to control blood pressure in patients with CKD (Strength of Recommendation B), and will frequently include a diuretic, which in stages 4-5 should be a loop diuretic (Strength of Recommendation B). - Renin-angiotensin-aldosterone system (RAAS) inhibitors are first choice drugs in patients with diabetic nephropathy, patients with non-diabetic nephropathy with a protein/creatinine ratio higher than 200 mg/g, and patients with heart failure (Strength of Recommendation A). The combination of ACEIs and ARBs is indicated for reducing proteinuria that remains high despite treatment with a RAAS inhibitor, provided potassium levels do not exceed 5.5 mEq/L (Strength of Recommendation B). - When RAAS blockers are started or their dose is changed in patients with advanced CKD, kidney function and serum potassium levels should be monitored at least after 1-2 weeks. DIAGNOSIS AND TREATMENT OF DYSLIPIDEMIA - A complete evaluation of the lipid profile including total cholesterol, LDL-C, HDL-C, and triglycerides should be performed in any patient with CKD at baseline and at least annually (Strength of Recommendation B). - In patients with stage 4-5 CKD and LDL-C >or= 100 mg/dL, treatment to decrease levels to < 100 mg/dL should be considered because of their high CV risk. This reduction is recommended in secondary prevention and in primary prevention in diabetic patients. Lipid-lowering treatment is recommended in all other patients, although no evidence showing its benefits is available yet (Strength of Recommendation C). - In patients with stage 4-5 CKD and triglyceride levels >or= 500 mg/dL which are not corrected by treating the underlying cases, treatment with triglyceride-lowering drugs may be considered to reduce the risk of pancreatitis. However, treatment with fibrates should be used with caution, and these drugs should not be associated to statins due to the risk of rhabdomyolysis (Strength of Recommendation C). There is little experience on the efficacy and safety of omega-3 fatty acids for the treatment of hypertriglyceridemia in patients with grade 4-5 CRF, but they may be considered a possibly safer alternative to fibrates (Strength of Recommendation C). SMOKING - Smoking is a cardiovascular risk factor and a risk factor for progression of kidney disease in patients with CRF (Strength of Recommendation B). - Use of active measures to achieve smoking cessation is recommended in patients with CRF (Strength of Recommendation C). HOMOCYSTEINE - Hyperhomocysteinemia has been postulated as a cardiovascular risk factor in the general population and in kidney patients, but the available evidence is not consistent. - There is no evidence that vitamin therapy decreases cardiovascular risk in patients with CRF, and recommendation of routine vitamin measurement and start of vitamin therapy to reduce cardiovascular risk in these patients is therefore questionable (Strength of Recommendation B). LEFT VENTRICULAR HYPERTROPHY - Left ventricular hypertrophy (LVH) is a cardiovascular risk factor in patients with CRF (Strength of Recommendation B). - It is advisable to perform an echocardiogram at baseline and every 12-24 months and to consider treatments allowing for LVH regression (Strength of Recommendation C). The approach to LVH should be early and multifactorial because its reversibility is limited once established (Strength of Recommendation C). - RAAS blockade with ACEIs or ARBs partially reverts LVH in patients with CRF (Strength of Recommendation B). ANTI-PLATELET AGGREGATION - Because of the high cardiovascular risk in patients with CKD, anti-platelet aggregant therapy, especially low-dose aspirin, would be indicated in patients with type 2 diabetes as primary prevention, and in all patients with CKD as secondary prevention. There is however no evidence of the benefits of anti-platelet aggregant therapy in primary prevention in patients with CKD, particularly in stages 4-5; indication for treatment in this situation should therefore be individualised because of its greater risk of bleeding. - Adequate good blood pressure control should previously be achieved to minimise the risk of haemorrhagic stroke (Strength of Recommendation C).
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PMID:[Arterial hypertension and dyslipidemia in patients with chronic kidney disease (CKD). Anti-platelet aggregation. Goal oriented treatment]. 1901 37

In the recent past, hyperhomocysteinemia (HHCY) has been linked to chronic heart failure. Folate and vitamin B12 deficiencies are the common causes of HHCY. The impact of these vitamins on cardiac function and morphology has scarcely been investigated. The aim of this study was to conduct an analysis of the cardiac effect of folate and vitamin B12 deficiency in vivo. Two groups of rats, a control (Co, n = 10) and a vitamin-deficient group (VitDef, n = 10), were fed for 12 weeks with a folate and vitamin B12-free diet or an equicaloric control diet. Plasma and tissue concentrations of HCY, S-adenosyl-homocysteine (SAH), S-adenosyl-methionine (SAM), and brain natriuretic peptide (BNP) were measured. Moreover, echocardiographic and histomorphometric analyses were performed. VitDef animals developed a significant HHCY (Co vs VitDef: 6.8 +/- 2.7 vs 61.1 +/- 12.8 micromol/l, P < 0.001). Fractional shortening, left ventricular dimension at end-diastole and end-systole, posterior wall thickness, perivascular collagen, mast cell number, and BNP tissue levels were comparable in VitDef and Co animals. Interstitial collagen (Co vs VitDef: 6.8 +/- 3.0 vs 4.5 +/- 2.1%, P < 0.05), plasma BNP (Co vs VitDef: 180 +/- 80 vs 70 +/- 60 ng/l, P < 0.05), and tissue HCY (Co vs VitDef: 0.13 +/- 0.07 vs 0.07 +/- 0.04 micromol/g protein, P < 0.05) were lower in VitDef animals. Folate and vitamin B12 deficiency do not affect cardiac function and morphology.
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PMID:The cardiac effects of prolonged vitamin B12 and folate deficiency in rats. 1939 44

Four decades of research on the link between hyperhomocysteinemia and cardiovascular disease has led to a crossroads. Several negative studies on the role of homocysteine-lowering B-vitamin therapy in reducing the risk of atherothrombotic cardiovascular disease have dampened enthusiasm for this important field of research. In this review, we assess the present state of homocysteine research and suggest potential avenues that would help to clarify the purported link between the plasma homocysteine level and cardiovascular risk. We address several questions raised by the findings of various basic, epidemiological and clinical studies and attempt to construct a framework that we believe will allow us to address the fundamental unresolved issues in this controversial area, specifically focusing on the risk of coronary vascular disease and cardiac failure. This review should allow researchers to deconstruct this complex field into separate areas that, when addressed adequately, may lead to findings that elucidate the overall link between hyperhomocysteinemia and cardiovascular disease and allow the design of appropriate clinical trials.
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PMID:Quo vadis: whither homocysteine research? 1948 90

Elevated level of homocysteine (Hcy) called hyperhomocysteinemia (HHcy) is one of the major risk factors for chronic heart failure. Although the role of Hcy in cardiac remodeling is documented, the regulatory mechanism involved therein is still nebulous. MicroRNAs (miRNAs) and dicer have been implicated in regulation of cardiovascular diseases. Dicer is the only known enzyme involved in miRNA maturation. We investigated the involvement of dicer and miRNA in Hcy-induced cardiac remodeling. HL-1 cardiomyocytes were cultured in different doses of Hcy. Total RNA was isolated and RT-PCR and real-time PCR was performed for dicer, MMP-2,-9, TIMP-1,-3, and NOX-4. MiRNA microarray was used for analyzing the differential expression of miRNAs. Individual miRNA assay was also done. Western blotting was used to assess the MMP-9 expression in HHcy cardiomyocytes. The RT-PCR results suggest that dicer expression is enhanced in HHcy cardiomyocytes suggesting its involvement in cardiac remodeling caused due to high dose of Hcy. On the other hand, high dose of Hcy increased NOX-4 expression, a marker for oxidative stress. Additionally, HHcy cardiomyocytes showed elevated levels of MMP-2,-9 and TIMP-1,-3, and reduced expression of TIMP-4, suggesting cardiac remodeling due to oxidative stress. The miRNA microarray assay revealed differential expression of 11 miRNAs and among them miR-188 show dramatic downregulation. These findings suggest that dicer and miRNAs especially miR-188 are involved in Hcy-induced cardiac remodeling.
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PMID:MicroRNAs are involved in homocysteine-induced cardiac remodeling. 1966 42

Cardiac hypertrophy has been demonstrated in rat models of hyperhomocysteinemia, a major risk factor for chronic heart failure. As one of the molecular pathway which leads to cardiac hypertrophy is mediated by the serine-threonine kinase DYRK1A, we have determined the expression of Dyrk1a in the heart of hyperhomocysteinemic rats and found that hyperhomocysteinemia in rats not only induced ventricular cardiomyocyte hypertrophy but also decreased protein Dyrk1a expression. The decreased expression of Dyrk1a could be consistent with decreased antihypertrophic effects of Dyrk1a leading to cardiomyocyte hypertrophy in case of hyperhomocysteinemia.
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PMID:Hyperhomocysteinemia-induced Dyrk1a downregulation results in cardiomyocyte hypertrophy in rats. 1990 49


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