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)

Prostaglandins (PG) are highly unsaturated, cyclic fatty acids with 20 carbon atoms which are biosynthesized from dihomo-gamma-linolenic, arachidonic and eicosapentaenoic acids. These fatty acids are either ingested or are biosynthesized from linoleic and linolenic acids, respectively. The PG-precursor fatty acids are liberated from membrane phospholipids by phospholipase A and are converted to prostaglandins by the multienzyme complex PG-synthetase. The activity of the PG-system is influenced by extracellular hormonal, neural and mechanical stimuli and by intracellular factors such as ion-concentration and activity of the enzymes adenyl- and guanylcyclase. Prostaglandins are tissue hormones or autacoids which act on their receptors near their site of synthesis and degradation. The prostaglandin family constitutes a group of more than 10 natural occurring compounds showing a variety of biological actions. In arteries and veins the different PG:s have vasodilating as well as vasoconstricting effects. In addition, they are involved in the regulation of vascular smooth muscle proliferation. Within the kidney PG:s have vascular and tubular actions. They antagonize the effect of ADH, mediate renin secretion and are involved in the control of electrolyte balance. In the regulation of platelet aggregation and platelet adhesion PG:s have opposite functions: Prostacyclin which is synthesized in the vascular wall antagonizes the aggregating action of Thromboxane A2 which is formed in the platelets. A defect or an imbalance in the production of PG:s in the vascular wall, in platelets or in the kidney is assumed to play a pathogenetic role in a variety of cardiovascular and renal diseases such as in hypertension, atherosclerosis, persistent ductus arteriosus and Bartter's syndrome.
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PMID:[Prostaglandins in cardiovascular and renal function. Biochemical, physiological and clinical findings (author's transl)]. 10 97

The aging kidney suffers reduction both in mass and in glomerular filtration rate. These changes may be totally or partially due to atherosclerosis and hypertension, which reduce renal blood flow. Superimposed on these processes, and perhaps responsible for primary loss of renal mass irrespective of renal vascular disease, is glomerular damage and involution that is a consequence of adaptive increases in glomerular perfusion pressure that occurs as the number of nephrons decline with age. The data available at this time do not allow us to distinguish between these two potential mechanisms of renal senescence. The decline in GFR is in turn responsible for reduced renal acidification and the reduced renal clearance of drugs that are normally removed by the kidney. Certain renal functions, however, are depressed to a greater extent than is GFR. Both the ability to maximally dilute the urine and to maximally concentrate it are controlled by serum ADH concentrations and by the action of that hormone on the collecting duct. Aged rats do not maximally secrete ADH under conditions of dehydration and the effect of ADH on the kidney is also attenuated. Elderly humans also cannot maximally suppress ADH secretion when serum osmolality is reduced. Likewise, the renin-angiotensin-aldosterone axis is poorly responsive to volume depletion in aging subjects. As a result, elderly individuals cannot maximally retain sodium under conditions of plasma volume contraction out of proportion to reduction in GFR. The kidney is the site of vitamin D1 hydroxylation. Hydroxylation of vitamin D is reduced out of proportion to any reduction in GFR in the rat. There are no data as yet available on the effect of aging and the production of erythropoietin, a principal regulator of red blood cell mass. Neither are there data available on changes that might occur with advancing age in the ability of the aging kidney to metabolize various hormones, such as parathyroid hormone, glucagon, and insulin. The mechanisms and the full biochemical and physiologic consequences of renal senescence remain to be fully elucidated.
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PMID:The aging kidney. 391

Numerous studies have shown that moderate drinking protects against coronary disease, but no mechanism for this effect has been established. In the present study we show that the B1 isoenzyme of alcohol dehydrogenase (ADH) is expressed in human blood vessels. Polymerase chain reaction (PCR) employing total human aortic cDNA as a template detected a 0.6 kb band, the nucleotide sequence of which is an identical match to the low Km (50 microM) B1 ADH isoenzyme nucleotide sequence. Immunoblot of vascular homogenates shows a 40 KDa band, i.e., the size of the B1 ADH subunit, and immunohistochemical studies of vessel sections demonstrate high density staining with anti-human ADH (Class I) but not control sera. These studies identify within blood vessels the existence of a metabolic pathway sensitive to low substrate concentrations and capable of producing a reductive (NADH) environment that could antagonize lipoprotein oxidation and hence could account for a protective effect of ethanol on atherosclerosis.
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PMID:Cardioprotective effects of alcohol: mediation by human vascular alcohol dehydrogenase. 794 38

Ten asthmatics in remission and aggravation of the disease were examined for: lipoprotein pre-beta, beta and alpha fractions, total cholesterol and its fractions in atherogenic and antiatherogenic lipoproteins with estimation of the atherogenicity coefficient, activity of 5-nucleotide hydrolase, acid phosphatase, gamma-glutamyl transpeptidase and alcohol dehydrogenase. The results were indicative of more active atherosclerotic process in the presence of blockade which changed the activity of hepatocyte membrane lipoprotein receptors, of simultaneous operation in bronchial asthma patients of infiltrative and cellular mechanisms of atherosclerosis.
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PMID:[Atherogenesis in bronchial asthma patients: its relationship to the pathogenetic characteristics of the disease and to liver function (the clinico-biochemical aspects)]. 814 74

Alcohol-induced oxidative stress is linked to the metabolism of ethanol. Three metabolic pathways of ethanol have been described in the human body so far. They involve the following enzymes: alcohol dehydrogenase, microsomal ethanol oxidation system (MEOS) and catalase. Each of these pathways could produce free radicals which affect the antioxidant system. Ethanol per se, hyperlactacidemia and elevated NADH increase xanthine oxidase activity, which results in the production of superoxide. Lipid peroxidation and superoxide production correlate with the amount of cytochrome P450 2E1. MEOS aggravates the oxidative stress directly as well as indirectly by impairing the defense systems. Hydroxyethyl radicals are probably involved in the alkylation of hepatic proteins. Nitric oxide (NO) is one of the key factors contributing to the vessel wall homeostasis, an important mediator of the vascular tone and neuronal transduction, and has cytotoxic effects. Stable metabolites--nitrites and nitrates--were increased in alcoholics (34.3 +/- 2.6 vs. 22.7 +/- 1.2 micromol/l, p < 0.001). High NO concentration could be discussed for its excitotoxicity and may be linked to cytotoxicity in neurons, glia and myelin. Formation of NO has been linked to an increased preference for and tolerance to alcohol in recent studies. Increased NO biosynthesis also via inducible NO synthase (NOS, chronic stimulation) may contribute to platelet and endothelial dysfunctions. Comparison of chronically ethanol-fed rats and controls demonstrates that exposure to ethanol causes a decrease in NADPH diaphorase activity (neuronal NOS) in neurons and fibers of the cerebellar cortex and superior colliculus (stratum griseum superficiale and intermedium) in rats. These changes in the highly organized structure contribute to the motor disturbances, which are associated with alcohol abuse. Antiphospholipid antibodies (APA) in alcoholic patients seem to reflect membrane lesions, impairment of immunological reactivity, liver disease progression, and they correlate significantly with the disease severity. The low-density lipoprotein (LDL) oxidation is supposed to be one of the most important pathogenic mechanisms of atherogenesis, and antibodies against oxidized LDL (oxLDL) are some kind of epiphenomenon of this process. We studied IgG oxLDL and four APA (anticardiolipin, antiphosphatidylserine, antiphosphatidylethanolamine and antiphosphatidylcholine antibodies). The IgG oxLDL (406.4 +/- 52.5 vs. 499.9 +/- 52.5 mU/ml) was not affected in alcoholic patients, but oxLDL was higher (71.6 +/- 4.1 vs. 44.2 +/- 2.7 micromol/l, p < 0.001). The prevalence of studied APA in alcoholics with mildly affected liver function was higher than in controls, but not significantly. On the contrary, changes of autoantibodies to IgG oxLDL revealed a wide range of IgG oxLDL titers in a healthy population. These parameters do not appear to be very promising for the evaluation of the risk of atherosclerosis. Free radicals increase the oxidative modification of LDL. This is one of the most important mechanisms, which increases cardiovascular risk in chronic alcoholic patients. Important enzymatic antioxidant systems - superoxide dismutase and glutathione peroxidase - are decreased in alcoholics. We did not find any changes of serum retinol and tocopherol concentrations in alcoholics, and blood and plasma selenium and copper levels were unchanged as well. Only the zinc concentration was decreased in plasma. It could be related to the impairment of the immune system in alcoholics. Measurement of these parameters in blood compartments does not seem to indicate a possible organ, e.g. liver deficiency.
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PMID:Oxidative stress, metabolism of ethanol and alcohol-related diseases. 1117 77

Membrane lipid peroxidation results in the production of a variety of aldehydic compounds that play a significant role in aging, drug toxicity and the pathogenesis of a number of human diseases, such as atherosclerosis and cancer. Increased lipid peroxidation and reduced antioxidant status may also contribute to the development of diabetic complications. This study reports that lipid peroxidation end products such as malondialdehyde (MDA) and 4-hydroxynonenal (HNE) induce aldehyde reductase (ALR) gene expression. MDA and HNE induce an increase in intracellular peroxide levels; N-Acetyl-L-cysteine (NAC) suppressed MDA- and HNE-induced ALR gene expression. These results indicate that increased levels of intracellular peroxides by MDA and HNE might be involved in the upregulation of ALR.
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PMID:Aldehyde reductase gene expression by lipid peroxidation end products, MDA and HNE. 1123 96

Alcohol dehydrogenase 1C (ADH1C or ADH3) genotype reportedly modifies the association between alcohol consumption and coronary heart disease (CHD) risk, as well as influencing plasma high-density lipoprotein (HDL) levels [Hines LM, Stampfer MJ, Ma J, et al. Genetic variation in alcohol dehydrogenase and the beneficial effect of moderate alcohol consumption on myocardial infarction. N Engl J Med 2001;344:549-55]. This relationship has been examined in a sample of middle-aged (50-61 years) men (total of 2773 with 220 CHD events), participating in the prospective Second Northwick Park Heart Study (NPHS II). Alcohol consumption was assessed by questionnaire as the number of units consumed in the previous week. Drinkers experienced lower CHD risk than abstainers [hazard ratio (HR) 0.73 (95% confidence intervals (CI) 0.53, 0.99; p=0.04)] and had significantly higher HDL and apolipoprotein (apo)AI concentrations (both p<0.0001) and a lower fibrinogen (p=0.02). Overall, there was no effect of ADHC1 gamma1>gamma2 genotype on plasma levels of HDL, apoAI or fibrinogen or on CHD risk. To consider whether the effect of alcohol consumption on risk was modulated by genotype, the men were divided into abstainers, modest drinkers (1-3 units/week) and those who consumed more than 3 units/week. Significant alcohol:genotype interaction on CHD risk was observed (p=0.02), with gamma2 homozygotes, who were modest drinkers, displaying 78% CHD risk reduction compared to gamma1 homozygotes (HR=0.22, 95% CI 0.05-0.94). There was, however, no association between genotype and apoAI, HDL or fibrinogen and this was not altered when alcohol intake was considered. These findings confirm that the cardiovascular benefit of modest alcohol consumption. ADH1C genotype modifies the relationship between alcohol consumption and CHD risk but at lower levels than previously reported.
Atherosclerosis 2005 Jun
PMID:Genetic variation in alcohol dehydrogenase 1C and the beneficial effect of alcohol intake on coronary heart disease risk in the Second Northwick Park Heart Study. 1591 Aug 47

We previously demonstrated that a functional polymorphism in alcohol dehydrogenase type 1C (ADH1C, also known as ADH3) modifies the association between moderate alcohol consumption and high-density lipoprotein (HDL) levels and risk of myocardial infarction among older men. In this study, we investigated the effect of the ADH1C gamma(1) and gamma(2) alleles on the relationship between alcohol consumption and HDL levels among four populations with varied exposure to endogenous and exogenous estrogens: premenopausal women, middle-to-older aged men, postmenopausal women currently using postmenopausal hormones (PMH) and postmenopausal women not currently using PMH. We observed an interaction between moderate alcohol consumption and ADH1C genotype on HDL level that was similar among middle-to-older aged men and postmenopausal women not using PMH. Among the moderate drinkers (approximately a half a drink per day for women and a full drink per day for men), there was a significant 5.3mg/dL (P=0.02) higher level of multivariate adjusted HDL level comparing the gamma(2) homozygotes (slow oxidizers) to the gamma(1) homozygotes (fast oxidizers). This interaction was not present among premenopausal women or postmenopausal women using PMH, who had higher overall HDL levels irrespective of alcohol consumption. Our results confirm that ADH1C genotype modifies the association between alcohol consumption and HDL levels among men and postmenopausal women not using PMH who drink moderately. However, this was not observed among individuals with estrogen-elevated HDL levels, specifically premenopausal women and postmenopausal women taking PMH, suggesting that these populations may benefit less from alcohol consumption with respect to coronary heart disease.
Atherosclerosis 2005 Oct
PMID:Alcohol consumption and high-density lipoprotein levels: the effect of ADH1C genotype, gender and menopausal status. 1605 Dec 48

Low ethanol intake is known to have a beneficial effect on cardiovascular disease. In cardiovascular disease, insulin resistance leads to altered glucose and lipid metabolism resulting in an increased production of aldehydes, including methylglyoxal. Aldehydes react non-enzymatically with sulfhydryl and amino groups of proteins forming advanced glycation end products (AGEs), altering protein structure and function. These alterations cause endothelial dysfunction with increased cytosolic free calcium, peripheral vascular resistance, and blood pressure. AGEs produce atherogenic effects including oxidative stress, platelet adhesion, inflammation, smooth muscle cell proliferation and modification of lipoproteins. Low ethanol intake attenuates hypertension and atherosclerosis but the mechanism of this effect is not clear. Ethanol at low concentrations is metabolized by low Km alcohol dehydrogenase and aldehyde dehydrogenase, both reactions resulting in the production of reduced nicotinamide adenine dinucleotide (NADH). This creates a reductive environment, decreasing oxidative stress and secondary production of aldehydes through lipid peroxidation. NADH may also increase the tissue levels of the antioxidants cysteine and glutathione, which bind aldehydes and stimulate methylglyoxal catabolism. Low ethanol improves insulin resistance, increases high-density lipoprotein and stimulates activity of the antioxidant enzyme, paraoxonase. In conclusion, we suggest that chronic low ethanol intake confers its beneficial effect mainly through its ability to increase antioxidant capacity and lower AGEs.
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PMID:Beneficial effect of low ethanol intake on the cardiovascular system: possible biochemical mechanisms. 1732 32

The alcohol dehydrogenase 1C gene (ADH1C) gamma2gamma2 variant reportedly interacts with moderate alcohol consumption to increase HDL-cholesterol levels and reduce coronary heart disease (CHD). We undertook replication studies in two large population cohorts of women and men. 3234 women and 1313 men with relevant genotypic and phenotypic data from two prospective population cohorts were genotyped for ADH1C variants. No association was found between ADH1C variants and HDL-cholesterol, blood pressure or incident CHD, although ADH1C was associated with alcohol consumption. There was no evidence of interactions between ADH1C variants and moderate alcohol intake on HDL-cholesterol, blood pressure or CHD incidence. Life-long women abstainers had adverse risk factor profiles. Our findings do not support the hypothesis that ADH1C variants are associated with CHD risk in people who drink moderately.
Atherosclerosis 2008 Feb
PMID:Alcohol dehydrogenase type 1C (ADH1C) variants, alcohol consumption traits, HDL-cholesterol and risk of coronary heart disease in women and men: British Women's Heart and Health Study and Caerphilly cohorts. 1737 29


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