Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

---

Query: EC:3.4.15.1 (ACE)
18,300 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Metabolic therapy involves the administration of a substance normally found in the body to enhance a metabolic reaction within the cell. This may be achieved in two ways. First, for some systems, a substance can be given to achieve greater than normal levels in the body so as to drive an enzymic reaction in a preferred direction. Second, metabolic therapy may be used to correct an absolute or relative deficiency of a cellular component. Thus, metabolic therapy differs greatly from most standard cardiovascular pharmacologic therapy such as the use of ACE Inhibitors b-blockers, statins and calcium channel antagonists that are given to block rather than enhance cellular processes. In this review we highlight some metabolic substances that have potential benefit in treating heart disease or improving outcomes after cardiovascular interventions. Glucose-insulin-potassium therapy is protective against myocardial ischaemia by elevating myocardial glycogen levels. Coenzyme Q(10) is a lipid-soluble antioxidant that plays a crucial role in cellular ATP production. Magnesium orotate, a key intermediate in the biosynthetic pathway of glycogen, has been shown to improve the energy status of the cell and improve recovery from cardioplegic arrest. The amino acid aspartate plays an important role in providing energy substrates for oxidative phosphorylation in the myocyte. By improving cellular energy production, metabolic therapy has the potential to benefit cardiac function during the stress of cardiac surgery, myocardial infarction and cardiac failure.
...
PMID:The principles of metabolic therapy for heart disease. 1635 48

It is widely accepted that a high sodium intake triggers blood pressure rise. However, only one-third of the normotensive subjects were reported to show salt-sensitivity in their blood pressure. Many factors have been proposed as causes of salt-sensitive hypertension, but none of them provides a satisfactory explanation. We propose, on the basis of accumulated data, that the reduced activity of the kallikrein-kinin system in the kidney may provide this link. Renal kallikrein is secreted by the distal connecting tubular cells and all kallikrein-kinin system components are distributed along the collecting ducts in the distal nephron. Bradykinin generated is immediately destroyed by carboxypeptidase Y-like exopeptidase and neutral endopeptidase, both quite independent from the kininases in plasma, such as angiotensin converting enzyme. The salt-sensitivity of the blood pressure depends largely upon ethnicity and potassium intake. Interestingly, potassium and ATP-sensitive potassium (K(ATP)) channel blockers accelerate renal kallikrein secretion and suppress blood pressure rises in animal hypertension models. Measurement of urinary kallikrein may become necessary in salt-sensitive normotensive and hypertensive subjects. Furthermore, pharmaceutical development of renal kallikrein releasers, such as K(ATP) channel blockers, and renal kininase inhibitors, such as ebelactone B, may lead to the development of novel antihypertensive drugs.
...
PMID:A missing link between a high salt intake and blood pressure increase. 1665 1

The First Hungarian Therapeutic Consensus Conference took place on 3rd Nov. 2003 with the participation of 9 medical societies. Over the past 2 years the results of new major studies have been published and the American ATP III has also updated its guidelines issued in 2004. Based on the above proposals, the Second Hungarian Therapeutic Consensus Conference held on 3rd Nov. 2005 partly confirmed its earlier suggestions, but made some changes as well. Within the high risk category the Conference optionally created a very high risk group from those patients who - in addition to their cardiovascular disease--have either diabetes or metabolic syndrome or acut coronaria syndrome or who are chain smokers. We have included - as a complement - into the asymptomatic high risk category such newly emerging risk factors, one of which already in itself means high risk: ankle/arm index < or = 0.9, GFR <60 ml/min, microalbuminuria (30-300 mg), preclinical atherosclerosis (plaque). Besides, 4 other risk factors were also categorised such as Lp/a (> or = 30 mg/dl), CRP (> or = 3mg/l), homocysteine (> or = 12 micromol), familiarity--atherogenic gene constellation, but only the presence of at least two of these verify high risk. In very high risk group the goals of 3.5 mmol/l and 1.8 mmol/l were determined as therapeutic option. The goal in obese patients--expressed earlier only in BMI--can now be equally determined by the abdominal circumference (94 cm for men, 80 cm for women respectively). ACE inhibitors were recommended earlier as a preventive therapy in case of dysfunction of the left ventricle, while at present they are suggested for all patients with cardiovascular disease. In the recent recommendations guidelines related to nutrition, smoking, exercise have also been included.
...
PMID:[New features in the recommendations of the Second Hungarian Therapeutic Consensus Conference]. 1699 15

VO(2) kinetics and O(2) deficit are important determinants of exercise tolerance. In "normal" conditions convective and diffusive O(2) delivery to skeletal muscle fibers do not represent important determinants of VO(2) kinetics, whose limiting factors seem mainly located within muscle fibers. Whereas a limiting role by PDH has not been confirmed, the role of inhibition of mitochondrial respiration by NO needs further investigations. Important determinants of skeletal muscle VO(2) kinetics likely reside in the interplay between bioenergetic mechanisms at exercise onset. By acting as high-capacitance energy buffers, PCr hydrolysis and anaerobic glycolysis would delay or attenuate the increase in [ADP] within muscle fibers following rapid increases in ATP demand, preventing a more rapid activation of oxidative phosphorylation. The different "localization" of the main limiting factors for VO(2) kinetics and VO(2)max offers the opportunity to perform a functional evaluation of oxidative metabolism at two different levels of the pathway for O(2), from ambient air to mitochondria. Whereas VO(2)max is mainly limited by the capacity of the cardiovascular system to deliver O(2) to exercising muscles, by analysis of VO(2) kinetics the functional evaluation is mainly related to skeletal muscle. In pathological conditions the situation may be less clear, and warrants further investigations.
...
PMID:Oxygen uptake kinetics: Why are they so slow? And what do they tell us? 1724 91

Cardioprotective interventions are defined as interventions able to increase myocardial resistance to ischemia. The authors approach the issue of cardioprotection on the basis of the present knowledge about the biochemical mechanisms responsible for the injury produced by myocardial ischemia or ischemia-reperfusion. Reversible and irreversible injury are distinguished. The former is largely accounted for by the direct consequences of reduced ATP synthesis, which causes decreased ATP phosphorylation potential, acidosis and phosphate accumulation. The biochemical mechanisms leading to irreversible injury include osmotic overload, production of toxic lipid metabolites, cytosolic calcium overload, and generation of reactive oxygen species, which lead to membrane disruption, mitochondrial dysfunction and possibly to the activation of apoptotic pathways. The major effect of the classical cardioprotective agents (nitrates, beta adrenergic antagonists, calcium channel blockers) consists in affecting ATP demand/supply ratio in such a way as to delay the decrease in ATP phosphorylation potential. Other drugs have been introduced, which allegedly interfere directly with the mechanisms responsible for irreversible ischemic injury. These include 3-ketoacyl-CoA tiolase inhibitors, modulators of intracellular calcium channels, ionic exchanger inhibitors, free radical scavengers, caspase inhibitors, purinergic agonists, K(+)(ATP) channel openers, and modulators of mitochondrial permeability transition. The results obtained with these substances in experimental models and in the clinical setting are discussed. Special attention is devoted to angiotensin converting enzyme inhibitors, whose direct cardioprotective properties has recently been demonstrated.
...
PMID:Biochemical basis of ischemic heart injury and of cardioprotective interventions. 1758 69

Ischemic heart disease is a major cause of morbidity and mortality in the world. Most of the existing therapeutic strategies used to treat ischemic heart disease aim at either increasing the oxygen supply to the heart (thrombolysis, revascularization, angiotensin converting enzyme inhibition and antiplatelet therapy) or decreasing the oxygen demand of the heart (beta-blockers and nitrates). Despite the fact that a compromised energy supply to the heart muscle is central to the pathology of ischemic heart disease, therapeutic approaches that focus on altering cardiac energy metabolism have not seen major clinical use. Therapeutic strategies in which the efficiency of oxygen utilization by the heart is enhanced could theoretically benefit the ischemic heart, and could have an additive benefit to existing therapeutic strategies. The energy supply for the heart (in the form of ATP) is normally provided by the balanced metabolism of both fatty acids (major part) and carbohydrates (minor part) oxidation. During reperfusion, this balance is broken by the dramatic enhancement of fatty acid oxidation and attenuation of carbohydrate oxidation, which results in intracellular H(+) accumulation and Ca(2+) overload. This article reviews the alterations in cardiac energy metabolism that occur in the ischemic heart, and discusses the existing and proposed pharmacologic therapies to optimize the balance of fatty acids and carbohydrate oxidation for the treatment of ischemic heart diseases.
...
PMID:Metabolic therapy for the treatment of ischemic heart disease: reality and expectations. 1803 28

Isolated rat hearts were studied by (31)P NMR and (13)C NMR. Hyperpolarized [1-(13)C]pyruvate was supplied to control normoxic hearts and production of [1-(13)C]lactate, [1-(13)C]alanine, (13)CO(2) and H(13)CO(-) (3) was monitored with 1-s temporal resolution. Hearts were also subjected to 10 min of global ischemia followed by reperfusion. Developed pressure, heart rate, oxygen consumption, [ATP], [phosphocreatine], and pH recovered within 3 min after the ischemic period. During the first 90 s of reperfusion, [1-(13)C]alanine and [1-(13)C]lactate appeared rapidly, demonstrating metabolism of pyruvate through two enzymes largely confined to the cytosol, alanine aminotransferase, and lactate dehydrogenase. (13)CO(2) and H(13)CO(-) (3) were not detected. Late after ischemia and reperfusion, the products of pyruvate dehydrogenase, (13)CO(2) and H(13)CO(-) (3) were easily detected. Using this multinuclear NMR approach, we established that during the first 90 s of reperfusion PDH flux is essentially zero and recovers within 20 min in reversibly-injured myocardium.
...
PMID:Inhibition of carbohydrate oxidation during the first minute of reperfusion after brief ischemia: NMR detection of hyperpolarized 13CO2 and H13CO3-. 1895 54

The nature of hemolytic effect induced by ethylene glycol alkyl ethers was analyzed taking into account G-6-PDH activity, ATP, pyruvate and thiols levels in peripheral blood of rats treated with single doses of 2-ethoxyethanol and 2-butoxyethanol. In addition, the susceptibility to autoxidation of rat erythrocyte lipids was evaluated. A decrease of ATP level in a dose-dependent manner and an increase in protein- and nonprotein-bound sulfhydryl groups were observed. These results indicate that an acute hemolytic effect of ethylene glycol alkyl ethers is not associated with alterations in G-6-PDH activity and the susceptibility of erythrocyte lipids to autoxidation. Increases in protein- and nonprotein-bound sulfhydryl groups seem to indicate the selective hemolysis of the aged erythrocytes. The increase in pyruvate and thiol levels may protect erythrocytes against the appearance of oxidative stress.
...
PMID:Studies on the nature of hemolytic effect induced by ethylene glycol alkyl ethers. 1905 82

Little is known on the metabolic profile of lung tumors and the reminiscence of embryonic features. Herein, we determined the bioenergetic profiles of human fibroblasts taken from lung epidermoid carcinoma (HLF-a) and fetal lung (MRC5). We also analysed human lung tumors and their surrounding healthy tissue from four patients with adenocarcinoma. On these different models, we measured functional parameters (cell growth rates in oxidative and glycolytic media, respiration, ATP synthesis and PDH activity) as well as compositional features (expression level of various energy proteins and upstream transcription factors). The results demonstrate that both the lung fetal and cancer cell lines produced their ATP predominantly by glycolysis, while oxidative phosphorylation was only capable of poor ATP delivery. This was explained by a decreased mitochondrial biogenesis caused by a lowered expression of PGC1alpha (as shown by RT-PCR and Western blot) and mtTFA. Consequently, the relative expression of glycolytic versus OXPHOS markers was high in these cells. Moreover, the re-activation of mitochondrial biogenesis with resveratrol induced cell death specifically in cancer cells. A consistent reduction of mitochondrial biogenesis and the subsequent alteration of respiratory capacity was also observed in lung tumors, associated with a lower expression level of bcl2. Our data give a better characterization of lung cancer cells' metabolic alterations which are essential for growth and survival. They designate mitochondrial biogenesis as a possible target for anti-cancer therapy.
...
PMID:Bioenergetics of lung tumors: alteration of mitochondrial biogenesis and respiratory capacity. 1971 47

Coenzyme Q10 (CoQ10) is essential for electron transport within the mitochondria and hence for ATP generation and cellular energy production. We recently demonstrated that plasma levels of CoQ10 are an independent predictor of survival in a cohort of 236 patients with chronic heart failure (CHF) followed for a median of 2.69 years. This is consistent with previous studies which have shown myocardial CoQ10 depletion in CHF, and correlated with the severity of the underlying disorder. Several intervention studies have been undertaken with CoQ10 in CHF, including randomized controlled trials with mostly positive outcomes in relation to improvement in plasma levels of CoQ10. A meta-analysis showed that CoQ10 resulted in an improvement in ejection fraction of 3.7% (95%CI 1.59-5.77) and the mean increase in cardiac output was 0.28 L/minute (95%CI 0.03-0.53). In a subgroup analysis, studies with patients not taking ACE inhibitors found a 6.7% increase in ejection fraction. The ongoing Q-SYMBIO trial will address whether CoQ10 supplementation improves survival in CHF patients. CoQ10 depletion may also be a contributory factor for why statin intervention has not improved outcomes in CHF. There is an emerging evidence base in support of CoQ10 as an adjunctive therapy in CHF.
...
PMID:Coenzyme Q10; an adjunctive therapy for congestive heart failure? 1996 71


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>

---