Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0004153 (atherosclerosis)
 77,401 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

An enzymatic activity of shuttle systems for reduction equivalents transport (malate-aspartate, glycerophosphate, lactate, glutamate and beta-hydroxybutyrate dehydrogenase) was studied spectrophotometrically in liver tissue of intact rabbits and animals with experimental atherosclerosis. Content of malate, oxaloacetate, glutamate, alpha-ketoglutarate, alpha-glycerophosphate, dihydroacetone phosphate, lactate, pyruvate, beta-hydroxybutyrate and acetoacetate were studied. In experimental atherosclerosis coordinated functioning of the enzymes, which participate in the utilization of the cytoplasmic NAD-H2 and the alteration in the ratio of reduced and oxidized metabolites in the systems, were found to be impaired.
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PMID:[The function of shuttle systems of liver extramitochondrial hydrogen transport in experimental atherosclerosis]. 0 20

The oxygen and glucose uptake, lactate formation, ATP/ADP and NADH/NAD ratios and incorporation of [14C]acetate and [14C]linolenic acid into lipids of early fatty streaks and more advanced complicated atherosclerotic lesions of human aorta were determined during aerobic and hypoxic incubation. Compared with grossly normal appearing sections of the aorta in intima and media preparations of early fatty streaks the oxygen uptake was increased while that in further developed atheroma was slightly diminished. Under aerobic incubation conditions the metabolic state of fatty streaks and atheroma was characterized by increased lactate formation, NADH/NAD ratio and incorporation of [14C]acetate and [14C]linolenic acid into the lipids, but by a lowered ATP/ADP ratio. More pronounced changes in these metabolic parameters were observed when the aortic tissue segments were incubated under hypoxic conditions. The analysis by argentation TLC of fatty acid methylesters derived from total lipids of aerobically incubated fatty streaks revealed an increased incorporation of [14C]acetate into the highly unsaturated long-chain fatty acids. In developed atherosclerotic lesions and in hypoxia the incorporation of radioacetate into the polyunsaturated fatty acids and the formation of 20:4 fatty acid from [14C]linolenic acid were, in contrast to the above finding, decreased while the synthesis of eicosatrienoic acid was increased. This finding suggests a block in the desaturation step of linoleic into 20:4 fatty acid in further developed atheroma and in hypoxia. In aerobically incubated atherosclerotic lesions and in hypoxia the palmitic acid was synthesized mainly by chain elongation while in grossly normal areas of the aorta at least part of this acid was synthesized de novo.
Atherosclerosis 1976 Sep
PMID:Comparative studies on fatty acid synthesis in atherosclerotic and hypoxic human aorta. 18 99

The authors investigated enzymic systems and corresponding substrate cycles that transport hydrogen across the mitochondrial membrane in a myocardium with experimental cholesterol-induced atherosclerosis. Sensitive spectrophotometric methods were used for assessing the activities of cytoplasmic and mitochondrial enzymes: lactate and alpha-glycerphosphate dehydrogenases, and of characteristic mitochondrial enzymes: glutamate and beta-hydroxybutyrate dehydrogenases. Specific enzymological methods were used in determining the concentrations of lactic, pyruvic, glycerophosphoric, dihydroacetonephosphoric, malic, oxaloacetic, glutamic, alpha-ketoglutaric, acetoacetic, and beta-hydroxybutyric acids. The cytoplasmic NAD/NADH quotient was calculated. The investigators found a reduction of enzymic activities in the "shuttle" transport system studied, marked deviations from normal levels of their substrates, and a reduction of the NAD/NADH quotient by the factor 0.56. All these phenomena represent a biochemical background of a complex of symptoms characterizing severe myocardial lesion in experimental atherosclerosis.
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PMID:Biochemical background of atherosclerotic heart lesion in an experiment. 20 32

Male rats were exposed to freshly generated cigarette smoke once daily for various lengths of time. Inhalation of smoke was verified by elevated levels of carboxyhemoglobin. Metabolism of arachidonate in the cardiovascular system to thromboxane and prostacyclin through the cyclooxygenase pathway and their further metabolism to 15-keto-derivatives, and to 12-hydroxyeicosatetraenoic acid (12-HETE) through lipoxygenase pathway was investigated. Synthesis of thromboxane and prostacyclin in platelets and aortas respectively was not changed within 8 weeks of smoke exposure. However, formation of 12-HETE in platelets was significantly increased after 4 weeks of smoke exposure. Catabolism of thromboxane and prostacyclin as determined by NAD(+)-dependent 15-hydroxyprostaglandin dehydrogenase activity was greatly decreased in lung but not in kidney and stomach following 4 weeks of smoke exposure. Increased 12-lipoxygenase activity in platelets may lead to stimulation of migration and proliferation of smooth muscle cells and to increased synthesis of leukotrienes in neutrophils. Decreased pulmonary prostaglandin catabolic activity may result in increase in circulating thromboxane/prostacyclin ratio and subsequently alteration of vascular homeostasis. The consequence of these biochemical changes may contribute to the development of atherosclerosis, thromboembolism and emphysema commonly found in smokers.
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PMID:Alterations of arachidonate metabolism in cardiovascular system by cigarette smoking. 212 9

Cellular components of the bronchovascular barrier have been studied in human lungs obtained after death of some patients with acute and chronic lung inflammatory diseases, hypertonic disease, atherosclerosis and chronic glomerulonephritis. Certain oxidative-reductive and hydrolytic enzymes, including NAD-, NADP- diaphorases, lactic dehydrogenase, acid and alkaline monophosphoesterase, ATP-ase, adenylate cyclase and nonspecific esterase were evaluated quantitatively after the histochemical processing of the specimens for the above reactions. Correlation analysis was performed for the bronchial epithelium, endotheliocytes, lymphocytes, plasma and mast cells, as well as macrophages and polymorphonuclear leucocytes. The results showed that there was a significant shift in some of the measured enzymic activities. Moreover, the correlations between different quantitative data were noted and these correlations changed with age. The increase in "rigidity" of the correlations in the elements of the bronchovascular barrier has been demonstrated during the process of ageing.
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PMID:Functional morphology of the bronchovascular barrier of the human lungs during various age periods. 214 10

Parallel stereo- and cytospectrophotometric examinations of human myocardial capillaries, 20-60 min after biological death were carried out. The activity of alkaline phosphatase, adenosine triphosphatase, lactate dehydrogenase and NAD-diaphorase in the capillary wall in relation to the sex and age in cardiovascular pathology, renal diseases and leukemias were studied. The permeability and level of energy supply of transendothelial transport were found to depend on the kind of the main pathological process and type of death. According to the parameters under study, the functional state of the capillary network of the myocardium in atherosclerosis with or without its combination with hypertension and also in secondary renal hypertension is described.
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PMID:[Stereological characteristics and enzymatic activity of myocardial capillaries in different variants of pathology and death (data from immediate autopsies)]. 686 Jan 68

Quantitative determination of the nucleotides AMP, ADP, ATP, GTP, NAD, NADP, 2,3-DPG and the free amino acids Lys, His, Gly, Ala, Val, Met, Phe, Tyr, Pro, Thr, Ser, Glu, Asp in erythrocytes was carried out in early and late stages of myocardial infarction. It was found that in erythrocytes, in the early stage of myocardial infarction, the concentrations of AMP, NADP and 2,3-DPG increased, whereas those of ADP, ATP, GTP and NAD decreased. In the third week of the disease the concentrations of AMP, ADP, NADP, and especially 2,3-DPG remained high, while those of ATP and GTP shifted towards the control. The concentrations of His, Gly, Ala, Val, Met, Phe, Thr and Glu increased, while those of Tyr, Ser and Asp decreased in the first stage of myocardial infarction. At the later stage of the illness (21 days) the concentrations of free amino acids returned to normal.
Atherosclerosis
PMID:Myocardial infarction. Changes in the concentrations of high-energy compounds and free amino acids in erythrocytes. 733 15

Study of the key mechanisms, metabolism regulators, showed that in the blood of patients with atherosclerosis the NAD/NAD . N ratio decreases by 59.8% and the NAD+ concentration by 44%, while the NAD . N content increases by 56.7%. In the nicotinamide adenine dinucleotide system there is a general tendency tomards accumulation:the concentration of NADP+ grows by 218.6% and that of NADP . N by 12.9%. A marked increase in the content of incompletely oxidized products is determined: lactic acid by 37.4%, alpha-glycerophosphate by 49.8%, dihydroxyacetone phosphate by 155%, oxaloacetate by 131% in the presence of lactate dehydrogenase and malate dehydrogenase activation. The detected changes are evidence of tissue energy debt in atherosclerosis, they reflect the character of metabolic acidosis formation and point to the presence of conditions for intensified liposynthesis.
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PMID:[Content of nicotinamide coenzymes, metabolites and the NAD-dependent dehydrogenase activity in the blood in arteriosclerosis]. 737 12

Cholesterol 7 alpha-hydroxylase, the key enzyme in bile acid synthesis, has been implicated in atherosclerosis and gallstone disease. The aim of this study was to check if the use of hydroxypropyl-beta-cyclodextrin (HPBCD), a vehicle for solubilizing cholesterol, augmented the rate of 7 alpha-hydroxycholesterol formation in hamster liver microsomes compared to classical assays in which labeled cholesterol was delivered in Tween 80. We observed that [14C]cholesterol carried by HPBCD enhanced the sensitivity of the assay tenfold. However, linearity of 7 alpha-hydroxycholesterol formation with time was short because of the rapid transformation of 7 alpha-hydroxycholesterol into 7 alpha-hydroxy-cholesten-3-one and 7 alpha,12 alpha-dihydroxy-cholesten-3-one when NADPH alone was present in the incubation medium. In order to avoid the transformation of 7 alpha-hydroxycholesterol into 7 alpha-hydroxy-cholesten-3-one, which is essentially NAD(+)-dependent, but is also NADP(+)-dependent, NADPH (1 mmol/l) plus an NADPH-regenerating system must be present in the medium. In this improved assay, the optimal pH was 7.4 and the apparent Km for control and cholestyramine-fed hamsters had a similar value of 315 mumol/l; linearity in the formation of 7 alpha-hydroxycholesterol was also apparent after a relatively short time period (10 min), but with a markedly greater slope of the curve. With a short incubation time (6 min), microsomes from livers of hamsters (five and nine weeks old) that were fed with a commercial ground diet yielded rates of 7 alpha-hydroxycholesterol formation of 115 +/- 10 and 150 +/- 16 pmol/min.mg protein, respectively, whereas microsomes from hamsters fed with a lithogenic sucrose-rich diet (five weeks old) yielded rates of 7 alpha-hydroxycholesterol formation of 77 +/- 7 pmol/min.mg protein, which were significantly lower (-33%) than those of corresponding control hamsters. This improved cholesterol 7 alpha-hydroxylase assay is very sensitive, simple and rapid, and does not necessitate sophisticated equipment. It can be particularly useful for determining cholesterol 7 alpha-hydroxylase activity in liver biopsies from dyslipidemic or lithiasic patients.
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PMID:Improved assay of hepatic microsomal cholesterol 7 alpha-hydroxylase activity by the use of hydroxypropyl-beta-cyclodextrin and an NADPH-regenerating system. 952 78

The endothelium modulates vascular tone by producing vasodilator and vasconstrictor substances. Of these, the best characterized and potentially most important are nitric oxide (NO.) and O2-.. These small molecules exhibit opposing effects on vascular tone and chemically react with each other in a fashion that negates their individual effects and leads to the production of potentially toxic substances, such as peroxynitrite (ONOO-). These dynamic interactions may likely have important implications, altering not only tissue perfusion but also contributing to the process of atherosclerosis. The precise O2-. source within vascular tissue remains to be determined. Recent work demonstrated that in endothelial cells as well as in vascular smooth muscle cells, a membrane-associated NAD(P)H-dependent oxidase represents the most significant O2-. source. Interestingly, this oxidase is activated upon stimulation with angiotension II, suggesting that under all conditions of an activated circulating and/or local renin-angiotensin system endothelial dysfunction secondary to increased vascular O2-. production is expected.
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PMID:Role for NADPH/NADH oxidase in the modulation of vascular tone. 1041 49


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