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)

On initial diagnosis or when metabolic control is poor, subjects with type 1 (insulin-dependent) diabetes mellitus often exhibit decreased high density lipoprotein (HDL) cholesterol levels, which have been associated in numerous studies in non-diabetic subjects with atherosclerosis and coronary artery disease. We measured the activities of plasma lecithin:cholesterol acyltransferase (LCAT), post-heparin lipoprotein lipase, and the composition of the HDL subfractions HDL2 and HDL3, in ten poorly controlled type 1 diabetic patients admitted to a metabolic ward (six women and four men, aged 18-37 years). The measurements were repeated after metabolic control had been optimised and again a week after discharge. The results were compared with those of ten healthy normolipidaemic subjects matched for age, sex and body mass. LCAT activity increased significantly (P < 0.05) with improved metabolic control in the diabetic patients, and showed positive within-person correlation with HDL2 cholesterol ester (r = 0.67; P < 0.01), HDL2 free cholesterol (r = 0.67; P < 0.01), phosphatidylcholine (r = 0.49; P < 0.05), total phospholipids (r = 0.50; P < 0.01) and apolipoprotein A-I (apo A-I: r = 0.72; P < 0.01). With improving metabolic control HDL2 lipid levels increased more than twofold and the compositional changes in HDL2 were reflected by an increased apo A-I:apo A-II ratio (P < 0.05) and a decreased triglyceride:apo A-I ratio (P < 0.05). Changes in HDL3 levels and composition were minor. The results of this study indicate that an increase in LCAT activity increases the concentration and changes the composition of HDL2 in type 1 diabetic patients with improved metabolic control.
Acta Diabetol 1993
PMID:Lecithin:cholesterol acyltransferase activity and high-density lipoprotein subfraction composition in type 1 diabetic patients with improving metabolic control. 811 Oct 77

Non-insulin-dependent diabetic (NIDDM) patients show a high incidence of cardiovascular disease, with greater risk of recurrent myocardial infarction and a less favourable clinical outcome than non-diabetic patients. The majority of NIDDM patients are treated with sulphonylurea (SU) derivatives. In the 1970's the University Group Diabetes Program concluded that tolbutamide treatment caused increased cardiovascular mortality; the study, which led to curtailment of oral antidiabetic treatment in the USA, was received with scepticism in Europe. Later criticism of its methodology reduced the impact of the study; however, the question of the safety of SU in NIDDM patients with cardiovascular disease has been re-opened in the face of new experimental data. The heart and vascular tissues do have prerequisites for SU action, i.e. SU receptors and ATP-dependent K+ (K+ATP) channels. These channels play an important role in the protection of the myocardium against ischaemia-reperfusion damage, and their closure by SU could lead to amplified ischaemic damage. Here we review evidence from animal and human studies for deleterious SU effects on ischaemia-induced myocardial damage, either by direct action or through diminished cardioprotective preconditioning. Closure of K+ATP channels by SU can lead to reduction of post-infarct arrhythmias; the drug has also been claimed to improve various atherosclerosis risk factors. The evidence for these beneficial effects of SU is also reviewed. We look at the major difficulties that hamper transfer of information from experimental studies to clinical decision-making: a) The affinity of SU for heart K+ATP channels is orders of magnitude lower than for beta-cell channels; is it reasonable to expect in vivo cardiac effects with therapeutic 'pancreatic' SU doses? b) Most studies utilized high doses of acutely administered SU; are effects similar in the chronic steady-state of the SU-treated diabetic patient? c) Convincing SU effects have been demonstrated in acutely induced ischaemia by acutely administering the drug; do such effects persist in the clinical situation of gradually progressive ischaemia? d) Ischaemia and modification of K+ATP channel activity induce complex events, some with opposing effects; what is the net result of SU action, and do different SU derivatives lead to different outcomes? e) In the chronic (and hence clinically relevant) situation, how can direct (deleterious or beneficial) SU effects be separated from beneficial effects mediated by the metabolic action of the drug? Only large prospective clinical studies, making use of advanced technology for assessment of cardiovascular function, can answer these questions. Millions of NIDDM patients are treated with SU derivatives; many are in the age group where cardiovascular risks are extremely high. The question of whether SU derivatives are beneficial or deleterious for these patients must finally be settle unequivocally.
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PMID:Sulphonylurea treatment of NIDDM patients with cardiovascular disease: a mixed blessing? 873 9

Diabetes is associated with increased oxidant stress. This may contribute to the development of diabetic macrovascular complications through increased oxidation of low-density lipoprotein (LDL), which is thought to be a crucial step in the development of atherosclerosis. The sulfonylurea gliclazide has been shown to have free radical-scavenging activity in vitro, but its effects on LDL oxidation, and these effects of other sulfonylureas, are unknown. To investigate this we studied the effects of in vitro supplementation with gliclazide 1 mumol/L on copper-induced oxidation of LDL isolated from 20 control subjects and 22 type II diabetic patients. The effects of 1 mumol/L vitamin C, a known water-soluble antioxidant, were studied simultaneously. The resistance to oxidation, expressed as the lag time between the addition of copper and commencement of oxidation, was significantly increased by both gliclazide and vitamin C, and the effect was similar for LDL from diabetic and control subjects. The baseline oxidation lag time was 63.4 +/- 2.1 minutes, and increased to 108 +/- 4.4 minutes with gliclazide and 88.7 +/- 5.6 minutes with vitamin C (P = .0001, baseline v either treatment). The increase in lag time with gliclazide of 70% +/- 3% was greater than the 30% +/- 5% increase with vitamin C (P < .0005). In a separate experiment, LDL isolated from eight control and 10 diabetic subjects was supplemented with 1 mumol/L gliclazide, glibenclamide, glipizide, and tolbutamide. For each LDL sample, all drugs were studied simultaneously and the oxidation lag time was compared against that of untreated LDL. Gliclazide increased the lag time from 53.7 +/- 2.4 minutes to 108.4 +/- 4.5 minutes (P = .0001). None of the other sulfonylureas had any effect on lag time. These findings demonstrate that gliclazide is an effective inhibitor of in vitro LDL oxidation, and in this respect, it is more potent on a molar basis than vitamin C. This antioxidant property of gliclazide was not shared by the other sulfonylureas studied.
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PMID:The effects of gliclazide and other sulfonylureas on low-density lipoprotein oxidation in vitro. 943 54

Patients with diabetes mellitus (DM), type 1 and type 2, have an increased risk of coronary heart disease as a result of accelerated atherosclerosis. Dyslipidemia, often found in these patients, plays an important role in this process. This study investigates the efficacy and safety of lipid-lowering therapy with pravastatin, a 3-HMG-Coenzym A reductase inhibitor in hypercholesterolemic type-1 and type-2 diabetic patients. Of 49 patients (22 type-1 DM and 27 type-2 DM), 24 patients were treated with pravastatin, 20 mg/day, and 25 patients with placebo. After 24 weeks, total cholesterol (TC) was decreased by 22.2%, low-density lipoprotein (LDL) cholesterol by 25.8% and triglycerides (TG) by 13.6%. Pravastatin treatment did not induce a significant change in high-density (HDL) cholesterol levels. No differences in effects of pravastatin treatment on serum lipids and lipoproteins were found with respect to the diabetes type. No serious side effects occurred and pravastatin treatment did not cause any deterioration in glycemia control. The data suggest that pravastatin is effective and safe in the treatment of dyslipidemia in both type-1 and type-2 diabetic patients.
Acta Diabetol 1997 Dec
PMID:Pravastatin in diabetes-associated hypercholesterolemia. 945 75

We evaluated the relationship between plasma fibrinogen concentration and the serum levels of interleukin-6 (IL-6), its soluble receptor, and their complex in patients with type 2 diabetes mellitus. The study comprised 57 patients with type 2 diabetes and 15 normal healthy controls. Serum levels of IL-6, soluble IL-6 receptor (IL-6R), and circulating IL-6/IL-6R complex were determined by enzyme-linked immunosorbent assays. Correlations between the different study parameters and serum IL-6, IL-6R, or IL-6/IL-6R complex levels were determined by multiple linear regression analysis. Any association between the different study parameters and the serum levels of IL-6, IL-6R, or IL-6/IL-6R complex were determined by stepwise linear regression analysis. The serum IL-6 level in diabetic subjects was significantly higher than in normal healthy controls (3.48 +/- 3.29 pg/ml vs 0.784 +/- 0.90 pg/ml, mean +/- SD, respectively, P = 0.0001). The specific optical density of the serum IL-6/IL-6R complex in diabetic patients was also significantly higher than in normal healthy controls, although there was no significant difference in the serum IL-6R level between diabetic patients and controls. The serum IL-6 concentration was correlated significantly with the HbA(1C) level (beta = 0.58, P = 0. 04) by multiple regression analysis. Stepwise regression analysis revealed that the levels of serum IL-6 (F = 8.251), HbA(1C) (F = 1. 08), and serum urea nitrogen (F = 5.603) were associated with the plasma fibrino gen concentration. These results suggest that hyperglycaemia and increased levels of serum IL-6 can increase the plasma fibrinogen concentration, one of the known risk factors for atherosclerosis in patients with type 2 diabetes mellitus.
Acta Diabetol 1999 Jun
PMID:Circulating levels of interleukin-6, its soluble receptor and interleukin-6/interleukin-6 receptor complexes in patients with type 2 diabetes mellitus. 1043 55

In this prospective study we aimed to compare insulin plus acarbose with insulin plus gliclazide with respect to their effect on insulin requirement, lipid profiles and body mass index (BMI) while achieving good glycemic control. Forty patients with type 2 diabetes mellitus who were on conventional insulin therapy (subcutaneous insulin therapy consisting of regular and NPH insulin, two times a day) were included in the study. They were randomized to double blind treatment with insulin in combination with gliclazide or acarbose for 6 months. For both groups, acceptable glycemic control was achieved at the end of study period. The mean HbA(1c) levels decreased from 8.32+/-0.26 to 7.13+/-0.18% in acarbose group and 8. 6+/-0.15 to 7.48+/-0.21% in the gliclazide group. The difference between groups was not significant (P 0.29). In the acarbose group, total cholesterol and LDL concentration decreased significantly while other parameters did not change. In the gliclazide group, HDL levels decreased significantly from 46.6+/-2.48 mg/dl to 41.3+/-2.09 mg/dl (P 0.001) BMI increased significantly from 27.60+/-1.21 kg/m(2) to 28.69+/-1.26 kg/m(2). (P 0.003) Total daily insulin dose was not changed in the acarbose group significantly, but increased from 42.6+/-2.73 to 49.27+/-3.58 U/day, which was significant in gliclazide group of (P 0.016). In the acarbose group, there were no significant differences between responders and nonresponders with respect to fasting and stimulated C-peptide, HbA(1c) levels and baseline BMI values. But in the gliclazide group, baseline BMI values were significantly higher in the nonresponding group compared to responders (P 0.02). In conclusion, combination of insulin with acarbose can be a good alternative for type 2 diabetic patients on insulin therapy; seems more beneficial than combination with gliclazide; may have advantage of achieving good glycemic control without increasing insulin dose and BMI; also may have the advantage of providing a decrease in LDL level, which are all important to prevent atherosclerosis.
Acta Diabetol 1999 Jun
PMID:Effects of combination of insulin and acarbose compared with insulin and gliclazide in type 2 diabetic patients. 1043 59

Patients with type 2 diabetes have a two- to four-fold greater risk of cardiovascular mortality than non-diabetic individuals. In order to prevent coronary events in the diabetic population, it is important to treat modifiable cardiovascular risk factors. Data from the Multiple Risk Factor Intervention Trial (MRFIT) show that serum cholesterol level, systolic blood pressure level and cigarette smoking were significant predictors of cardiovascular disease mortality in men with and without diabetes. At every risk factor level, the absolute risk of age-adjusted coronary death rate was three times greater for diabetic men than non-diabetic men (p<0.0001). Patients with diabetes have an abnormal (dyslipidaemic) lipoprotein profile with high levels of very low density lipoprotein cholesterol and triglycerides, and a low level of high density lipoprotein cholesterol. Although levels of total cholesterol or low density lipoprotein (LDL) cholesterol do not differ significantly between patients with and without diabetes, those with diabetes have higher levels of atherogenic small dense LDL particles. MRFIT data show that at any serum cholesterol level, diabetes confers two-three times the risk for a coronary event. These findings constitute the rationale for considering hypolipaemic therapy, e.g. with HMG-CoA reductase inhibitors (statins), in diabetic patients with dyslipidaemia, particularly in those with evidence of coronary heart disease. Evidence shows that statins significantly lower cholesterol, exhibit beneficial effects on many components of atherosclerosis, and can significantly reduce the incidence of stroke.
Acta Diabetol 2001
PMID:CHD: a major burden in type 2 diabetes. 1182 51

We investigated the effect of incubation of high density lipoprotein (HDL) under hyperglycaemic conditions on lipid composition, physicochemical properties and activity of paraoxonase (PON), a calcium-dependent enzyme associated with HDL that contributes to the antiatherogenicity of this lipoprotein. HDL incubated for three days with various glucose concentrations (0-100 mM) had significant increases in thiobarbituric acid-reactive substances (TBARS) and conjugated dienes with respect to control HDL. These results suggest that lipid peroxidation accompanies HDL glycation in vitro. The susceptibility to lipid peroxidation was higher in HDL isolated from subjects with low HDL-paraxonase activity with respect to subjects with higher HDL-PON activity. The lipid compositional changes were associated with modifications of apoprotein conformation as shown by the red-shifted position of the maximum emission of tryptophan in treated HDL. The decrease in the Gp (generalized polarization) value and the red-shifted position of the maximum emission of Laurdan incorporated in treated HDL demonstrate modifications of order and polarity with respect to control HDL. The negative correlation established between the Gp value and TBARS demonstrates that the modifications in molecular order are likely related to the increase in lipid peroxidation products. The activity of paraoxonase was significantly decreased in HDL incubated at 37 degrees C; a greater decrease occurred in the presence of 50 mM and 100 mM glucose. This study demonstrates modifications of lipid composition, apoprotein conformation and physicochemical properties of HDL incubated in the presence of glucose. These modifications affect the activity of HDL-associated paraoxonase. The physicochemical properties of lipoproteins play a regulatory role in lipoprotein function. The modification of order and polarity of glycated HDL and the alterations in paraoxonase activity could potentially contribute to the accelerated atherosclerosis in diabetic patients.
Acta Diabetol 2001 Dec
PMID:Effect of glycation of high density lipoproteins on their physicochemical properties and on paraoxonase activity. 1185 94

Both type I and type II diabetes are powerful and independent risk factors for coronary artery disease (CAD), stroke, and peripheral arterial disease. Atherosclerosis accounts for virtually 80% of all deaths among diabetic patients. Prolonged exposure to hyperglycemia is now recognized a major factor in the pathogenesis of atherosclerosis in diabetes. Hyperglycemia induces a large number of alterations at the cellular level of vascular tissue that potentially accelerate the atherosclerotic process. Animal and human studies have elucidated three major mechanisms that encompass most of the pathological alterations observed in the diabetic vasculature: 1) Nonenzymatic glycosylation of proteins and lipids which can interfere with their normal function by disrupting molecular conformation, alter enzymatic activity, reduce degradative capacity, and interfere with receptor recognition. In addition, glycosylated proteins interact with a specific receptor present on all cells relevant to the atherosclerotic process, including monocyte-derived macrophages, endothelial cells, and smooth muscle cells. The interaction of glycosylated proteins with their receptor results in the induction of oxidative stress and proinflammatory responses 2) oxidative stress 3) protein kinase C (PKC) activation with subsequent alteration in growth factor expression. Importantly, these mechanisms may be interrelated. For example, hyperglycemia-induced oxidative stress promotes both the formation of advanced glycosylation end products and PKC activation.
Cardiovasc Diabetol 2002 Apr 08
PMID:How hyperglycemia promotes atherosclerosis: molecular mechanisms. 1211 59

We evaluated the possible additive effect of overweight and diabetes in the occurrence of coronary heart disease (CHD) and stroke, and their interaction with other established risk factors. In a cross-sectional study, we evaluated the frequency of CHD and stroke in four groups of subjects: (1) lean non-diabetic subjects (n=250); (2) lean diabetic subjects (n=269); (3) overweight non-diabetic subjects (n=203); and (4) overweight diabetic subjects (n=446). CHD was more frequent among diabetic subjects, and even more among overweight diabetic subjects; stroke was more frequent among diabetic subjects, but equally frequent in overweight and in lean diabetic subjects. At multiple logistic regression analysis, age, arterial hypertension, diabetes were independent risk factors for CHD and for stroke; BMI and hyperlipidemia were risk factors only for CHD. CHD was an independent risk factor for stroke, and stroke was a risk factor for CHD. We conclude that obesity and diabetes are additional risk factors for CHD but not for stroke. The value of established risk factors such as arterial hypertension and hyperlipidemia in determining the appearance of CHD and stroke is maintained in the presence overweight and diabetes. Finally, CHD is frequently associated with stroke, suggesting a common process of atherosclerosis underlying both diseases.
Acta Diabetol 2002 Jun
PMID:Additive effect of overweight and type 2 diabetes in the appearance of coronary heart disease but not of stroke: a cross-sectional study. 1212 Sep 18


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