beta-carotene and Myocardial-Infarction

Topics: Adult; Aged; Aged, 80 and over; Antioxidants; beta Carotene; Cardiovascular Diseases; Carotenoids; Cohort Studies; Diet; Female; Humans; Male; Middle Aged; Myocardial Infarction; Randomized Controlled Trials as Topic

An exonic polymorphism (Y402H) in the complement factor H (CFH) gene, which locates within the binding sites for heparin and C-reactive protein, has recently been described and hypothesized to play an important role in atherothrombosis.. We, therefore, evaluated the CFH genetic variant Y402H amongst 685 Caucasian individuals who subsequently developed arterial or venous thrombotic event (incident myocardial infarction (MI), ischaemic stroke, or venous thromboembolism) and amongst 685 age- and smoking-matched Caucasian individuals who remained free of reported vascular disease during follow-up (controls) within the Physicians' Health Study cohort.. Genotype distribution for the polymorphism tested was in Hardy-Weinberg equilibrium in the control group. In contrast to expected results, we found no association of Y402H polymorphism with risk of atherothrombosis (adjusted: myocardial infarction, OR=1.09, 95%CI 0.88-1.36, p=0.43; ischaemic stroke, OR=1.11, 95%CI 0.81-1.54, p=0.52; venous thromboembolism, OR=1.41, 95%CI 0.88-2.24, p=0.15), nor with baseline plasma C-reactive protein levels [median (interquartile range) mg/L: YY, 1.39 (0.70-2.60); YH, 1.10 (0.57-2.16); HH, 1.00 (0.48-1.79); p=0.14].. In this large, prospective cohort of apparently healthy Caucasian men, we found no association of the complement factor H Y402H gene polymorphism with risk of incident thromboembolic events, nor with baseline levels of C-reactive protein.

Topics: Adult; Aged; Aged, 80 and over; Aspirin; beta Carotene; Brain Ischemia; C-Reactive Protein; Cardiovascular Diseases; Case-Control Studies; Complement Factor H; Gene Frequency; Genetic Predisposition to Disease; Genotype; Humans; Incidence; Male; Middle Aged; Myocardial Infarction; Platelet Aggregation Inhibitors; Polymorphism, Genetic; Prospective Studies; Risk Factors; Stroke; Venous Thrombosis; Vitamins; White People

To evaluate the 6-year post-trial effects of alpha-tocopherol and beta-carotene supplementation on coronary heart disease (CHD) in the alpha-tocopherol, beta-carotene cancer prevention (ATBC) study.. 29,133 male smokers, aged 50-69 years were randomised to receive alpha-tocopherol 50 mg, or beta-carotene 20 mg, or both, or placebo daily for 5-8 years. At the beginning of the post-trial follow-up, 23,144 men were still at risk for a first-ever major coronary event (MCE), and 1255 men with pre-trial history of myocardial infarction (MI) were at risk for MCE. Post-trial risk for MCE (n=2059) was 0.95 (95% confidence interval 0.87-1.04) among alpha-tocopherol recipients compared with non-recipients, and 1.14 (1.04-1.24) among beta-carotene recipients compared with non-recipients. The risk for non-fatal MI (n=993) was 0.96 (0.85-1.09) and 1.16 (1.03-1.32), and for fatal CHD (n=1066) 0.94 (0.83-1.06) and 1.11 (0.99-1.25), respectively. Among men with pre-trial MI no effects were observed in post-trial risk of MCE (n=257).. beta-Carotene seemed to increase the post-trial risk of first-ever non-fatal MI but there is no plausible mechanism to support it. Our findings do not advocate the use of alpha-tocopherol or beta-carotene supplements in prevention of CHD among male smokers.

Topics: Aged; alpha-Tocopherol; Antioxidants; beta Carotene; Coronary Disease; Dietary Supplements; Double-Blind Method; Humans; Male; Middle Aged; Myocardial Infarction; Risk Factors; Smoking; Survival Analysis

We have investigated the effect of modest supplementation with alpha-tocopherol (100 mg/day), beta-carotene (6 mg/day), vitamin C (100 mg/day) and selenium (50 microg/day) on oxidative stress and chromosomal damage, and the influence of methylenetetrahydrofolate reductase (MTHFR) genotype on these end-points. Subjects were two groups of middle-aged men differing in cardiovascular risk; 46 survivors of myocardial infarction before age 50 and 60 healthy controls. They were randomly divided into equal groups to receive antioxidants or placebo for 12 weeks. Twenty-eight patients and 58 controls completed the intervention. Micronucleus levels in peripheral lymphocytes and changes seen after intervention were studied in relation to the MTHFR C677T genotype, basal homocysteine and plasma folate levels. Ferric reducing ability of plasma and concentration of malondialdehyde were measured to assess the antioxidant effect of supplementation. There was no association of micronuclei with folate, homocysteine or malondialdehyde levels before supplementation. Micronucleus frequencies and plasma folate levels did not vary significantly with MTHFR genotype. Homocysteine levels in subjects with the TT variant genotype were significantly higher compared with CT or CC (P = 0.001), especially in subjects with low folate (P = 0.012). In the placebo control group an increase in micronuclei (P = 0.04) was detected at the end of the intervention period. This effect was not seen in the supplemented group. In antioxidant-supplemented myocardial infarction survivors we found an increase in the ferric reducing ability of plasma (P < 0.001) and a decrease in malondialdehyde (P = 0.001). Micronucleus frequency showed a decrease, strongest in subjects with normal folate levels (P = 0.015). In subjects with low folate levels, a high correlation was found between micronuclei after supplementation and homocysteine, both before (r = 0.979, P = 0.002) and after supplementation (r = 0.922, P = 0.009). Thus, folate deficiency may amplify the effect of other risk factors such as elevated homocysteine levels or variant MTHFR genotype, as well as influencing the ability of antioxidant supplementation to protect against genetic damage.

Topics: alpha-Tocopherol; Antioxidants; Ascorbic Acid; beta Carotene; Cardiovascular Diseases; Dietary Supplements; DNA Damage; Folic Acid; Folic Acid Deficiency; Genotype; Humans; Male; Methylenetetrahydrofolate Reductase (NADPH2); Micronucleus Tests; Middle Aged; Myocardial Infarction; Oxidative Stress; Selenium

To examine the development of age-related cataract in a trial of beta carotene supplementation in men.. Randomized, double-masked, placebo-controlled trial.. Male US physicians aged 40 to 84 years (n = 22 071) were randomly assigned to receive either beta carotene (50 mg on alternate days) or placebo for 12 years.. Age-related cataract and extraction of age-related cataract, defined as an incident, age-related lens opacity, responsible for a reduction in best-corrected visual acuity to 20/30 or worse, based on self-report confirmed by medical record review.. There was no difference between the beta carotene and placebo groups in the overall incidence of cataract (998 cases vs 1017 cases; relative risk [RR], 1.00; 95% confidence interval [CI], 0.91-1.09) or cataract extraction (584 vs 593; RR, 1.00; 95% CI, 0.89-1.12). In subgroup analyses, the effect of beta carotene supplementation appeared to be modified by smoking status at baseline (P =.02). Among current smokers, there were 108 cases of cataract in the beta carotene group and 133 in the placebo group (RR, 0.74; 95% CI, 0.57-0.95). Among current nonsmokers, there was no significant difference in the number of cases in the 2 treatment groups (884 vs 881; RR, 1.03; 95% CI, 0.94-1.13). The results for cataract extraction appeared to be similarly modified by baseline smoking status (P =.05).. Randomized trial data from a large population of healthy men indicate no overall benefit or harm of 12 years of beta carotene supplementation on cataract or cataract extraction. However, among current smokers at baseline, beta carotene appeared to attenuate their excess risk of cataract by about one fourth.

Topics: Adult; Aged; Aged, 80 and over; Aging; Anti-Inflammatory Agents, Non-Steroidal; Antioxidants; Aspirin; beta Carotene; Cataract; Cataract Extraction; Double-Blind Method; Humans; Incidence; Male; Middle Aged; Myocardial Infarction; Physicians; Proportional Hazards Models; Risk; United States; Visual Acuity

There is clear evidence from numerous randomized trials and their meta-analyses that aspirin reduces risks of first myocardial infarction (MI). Recent data also suggest that other nonsteroidal anti-inflammatory drugs (NSAIDs) may interfere with this benefit of aspirin.. We performed subgroup analysis from a 5-year randomized, double-blind, placebo-controlled trial of 325 mg aspirin on alternate days among 22 071 apparently healthy US male physicians with prospective observational data on use of NSAIDs. A total of 378 MIs were confirmed, 139 in the aspirin group and 239 in the placebo group. Aspirin conferred a statistical extreme (P<0.00001) 44% reduction in risk of first MI. Among participants randomized to aspirin, use of NSAIDs on 1 to 59 d/y was not associated with MI (multivariable adjusted relative risk [RR], 1.21; 95% confidence interval [CI], 0.78 to 1.87), whereas the use of NSAIDs on > or =60 d/y was associated with MI (RR, 2.86; 95% CI, 1.25 to 6.56) compared with no use of NSAIDs. In the placebo group, the RRs for MI across the same categories of NSAID use were 1.14 (95% CI, 0.81 to 1.60) and 0.21 (95% CI, 0.03 to 1.48).. These data suggest that regular but not intermittent use of NSAIDs inhibits the clinical benefits of aspirin. Chance, bias, and confounding remain plausible alternative explanations, despite the prospective design and adjustment for covariates. Nonetheless, we believe the most plausible interpretation of the data to be that regular but not intermittent use of NSAIDs inhibits the clinical benefit of aspirin on first MI.

Topics: Adult; Aged; Aged, 80 and over; Anti-Inflammatory Agents, Non-Steroidal; Aspirin; beta Carotene; Cohort Studies; Double-Blind Method; Follow-Up Studies; Humans; Likelihood Functions; Male; Middle Aged; Myocardial Infarction; Physicians; Prospective Studies; Regression Analysis; Risk; Surveys and Questionnaires; United States

Prospective studies have shown that C-reactive protein (CRP) can be used to predict risk of future cardiovascular events. High-sensitivity methods for CRP (hs-CRP) measurement are needed for this purpose.. We compared the clinical efficacy of an automated and commercially available latex-enhanced assay (Latex) for hs-CRP (Dade Behring) to a validated in-house ELISA, previously shown to predict future peripheral arterial disease (PAD) in asymptomatic populations. Using a prospective, nested, case-control design, we measured baseline hs-CRP concentrations in 144 apparently healthy men who subsequently developed symptomatic PAD and 144 age- and smoking habit-matched controls who remained free of vascular disease over the follow-up period of 60 months.. The two hs-CRP assays correlated highly (r = 0.95; P <0.001), and all but two participants were classified into concordant quartiles or varied by only one quartile. The median hs-CRP of the case group was significantly higher than that of controls when measured by either the ELISA (1.34 vs 0.99 mg/L; P = 0.034) or the Latex method (1.80 vs 1.20 mg/L; P = 0.042). Furthermore, for both ELISA and the Latex method, the calculated relative risks of developing PAD increased significantly with each increasing quartile of hs-CRP. The calculated interquartile increase in relative risk of PAD was 31% (95% confidence interval, 5.2-62.2%; P = 0.01) for ELISA and 34% (95% confidence interval, 8.2-66.1%; P = 0.007) for the Latex method.. Our findings indicate that the Latex method is equally as efficacious as the validated ELISA in classifying patients into cutoff points established by prospective studies for risk stratification for coronary and cerebrovascular disease.

Topics: Aged; Aged, 80 and over; Antioxidants; Aspirin; beta Carotene; C-Reactive Protein; Case-Control Studies; Double-Blind Method; Enzyme-Linked Immunosorbent Assay; Humans; Immunoassay; Latex; Male; Middle Aged; Myocardial Infarction; Peripheral Vascular Diseases; Platelet Aggregation Inhibitors; Prospective Studies; Risk Factors; Sensitivity and Specificity; Stroke

The intercellular adhesion molecule ICAM-1 mediates adhesion and transmigration of leucocytes to the vascular endothelial wall, a step proposed to be critical in the initiation and progression of atherosclerosis. Whether concentrations of soluble ICAM-1 (sICAM-1) are raised in apparently healthy individuals who later suffer acute myocardial infarction is unknown.. We obtained baseline plasma samples from a prospective cohort of 14,916 healthy men enrolled in the Physicians' Health Study. With a nested case-control design, we measured sICAM-1 concentrations for 474 participants who developed a first myocardial infarction, and 474 controls (participants who remained healthy throughout the 9-year follow-up). Cases were matched to controls according to age and smoking status at the time of myocardial infarction.. We found a significant association between increasing concentration of sICAM-1 and risk of future myocardial infarction (p = 0.003), especially among participants with baseline sICAM-1 concentrations in the highest quartile (> 260 ng/mL; relative risk 1.6 [95% Cl 1.1-2.4], p = 0.02). This association was present overall as well as among non-smokers, and persisted after control for lipid and non-lipid risk factors. In multivariate analyses, the risk of future myocardial infarction was 80% higher for participants with baseline sICAM-1 concentrations in the highest quartile (relative risk 1.8 [1.1-2.8], p = 0.02). Similar risk estimates were seen among non-smokers. We found slight but significant correlations between sICAM-1 and fibrinogen, high-density-lipoprotein cholesterol, homocysteine, triglycerides, tissue-type plasminogen-activator antigen, and C-relative protein, but adjustment for these altered the risk little. The risk of myocardial infarction associated with raised concentrations of sICAM-1 seemed to increase with length of follow-up.. Our data support the hypothesis that cellular mediators of inflammation have a role in atherogenesis and provide a clinical basis to consider antiadhesion therapies as a novel means of cardiovascular disease prevention.

Topics: Antioxidants; Arteriosclerosis; Aspirin; beta Carotene; Case-Control Studies; Double-Blind Method; Humans; Intercellular Adhesion Molecule-1; Male; Middle Aged; Multivariate Analysis; Myocardial Infarction; Platelet Aggregation Inhibitors; Prospective Studies; Risk Factors

Oxidized low-density lipoprotein is involved in the pathogenesis of atherosclerosis. In epidemiological studies antioxidants have been inversely related with coronary heart disease. Findings from controlled trials are inconclusive.. We studied the primary preventive effect of vitamin E (alpha tocopherol) and beta carotene supplementation on major coronary events in the Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study, a controlled trial undertaken primarily to examine the effects of these agents on cancer. A total of 27 271 Finnish male smokers aged 50 to 69 years with no history of myocardial infarction were randomly assigned to receive vitamin E (50 mg), beta carotene (20 mg), both agents, or placebo daily for 5 to 8 years (median, 6.1 years). The end point was the first major coronary event, either nonfatal myocardial infarction (surviving at least 28 days; n = 1204) or fatal coronary heart disease (n = 907).. The incidence of primary major coronary events decreased 4% (95% confidence interval, -12% to 4%) among recipients of vitamin E and increased 1% (95% confidence interval, -7% to 10%) among recipients of beta carotene compared with the respective nonrecipients. Neither agent affected the incidence of nonfatal myocardial infarction. Supplementation with vitamin E decreased the incidence of fatal coronary heart disease by 8% (95% confidence interval, -19% to 5%), but beta carotene had no effect on this end point.. Supplementation with a small dose of vitamin E has only marginal effect on the incidence of fatal coronary heart disease in male smokers with no history of myocardial infarction, but no influence on nonfatal myocardial infarction. Supplementation with beta carotene has no primary preventive effect on major coronary events.

Topics: Aged; beta Carotene; Cardiovascular Agents; Coronary Disease; Dietary Supplements; Female; Humans; Incidence; Male; Middle Aged; Myocardial Infarction; Risk; Treatment Outcome; Vitamin E

To evaluate the effects of alpha tocopherol and beta carotene supplements on recurrence and progression of angina symptoms, and incidence of major coronary events in men with angina pectoris.. Placebo controlled clinical trial.. The Finnish alpha tocopherol beta carotene cancer prevention study primarily undertaken to examine the effects of alpha tocopherol and beta carotene on cancer.. Male smokers aged 50-69 years who had angina pectoris in the Rose chest pain questionnaire at baseline (n = 1795).. alpha tocopherol (vitamin E) 50 mg/day, beta carotene 20 mg/day or both, or placebo in 2 x 2 factorial design.. Recurrence of angina pectoris at annual follow up visits when the questionnaire was readministered; progression from mild to severe angina; incidence of major coronary events (non-fatal myocardial infarction and fatal coronary heart disease).. There were 2513 recurrences of angina pectoris during follow up (median 4 years). Compared to placebo, the odds ratios for recurrence in the active treatment groups were: alpha tocopherol only 1.06 (95% confidence interval (CI) 0.85 to 1.33), alpha tocopherol and beta carotene 1.02 (0.82 to 1.27), beta carotene only 1.06 (0.84 to 1.33). There were no significant differences in progression to severe angina among the groups given supplements or placebo. Altogether 314 major coronary events were observed during follow up (median 5.5 years) and the risk for them did not differ significantly among the groups given supplements or placebo.. There was no evidence of beneficial effects for alpha tocopherol or beta carotene supplements in male smokers with angina pectoris, indicating no basis for therapeutic or preventive use of these agents in such patients.

Topics: Aged; Angina Pectoris; beta Carotene; Coronary Disease; Double-Blind Method; Follow-Up Studies; Humans; Logistic Models; Male; Middle Aged; Myocardial Infarction; Prognosis; Recurrence; Smoking; Vitamin E

The objective of this study was to examine whether definite hypertension and borderline isolated systolic hypertension predict subsequent cardiovascular disease and mortality.. This was a prospective cohort study with a mean follow-up of 11.7 years. The subjects were a group of 18,682 apparently healthy US men, aged 40 to 84 years, participating in the Physicians' Health Study, a randomized trial of low-dose aspirin and beta-carotene. The main outcome measures were total cardiovascular disease, myocardial infarction, stroke, cardiovascular death, and all-cause mortality. Hypertension was associated with substantially increased risks of total cardiovascular disease (relative risk [RR] 1.92; 95% confidence interval [CI], 1.70 to 2.18), myocardial infarction (RR,1.78; 95% CI, 1.49 to 2.13), stroke (RR, 2.19; 95% CI, 1.78 to 2.69), and cardiovascular death (RR, 2.10; 95% CI, 1.68 to 2.63). Borderline isolated systolic hypertension was associated with significantly increased risks of cardiovascular disease (RR, 1.32; 95% CI, 1.09 to 1.59), stroke (RR, 1.42; 95% CI, 1.04 to 1.93), and cardiovascular death (RR, 1.56; 95% CI, 1.13 to 2.15), as well as a possible but non-significant increased risk of myocardial infarction (RR, 1.26; 95% CI, 0.95 to 1.67). Hypertension and borderline isolated systolic hypertension were associated with significantly increased risks of 41% and 22%, respectively, for all-cause mortality.. Hypertension as well as borderline isolated systolic hypertension are associated with elevated risks of cardiovascular diseases, especially stroke and cardiovascular death. Hypertension is associated with an increased risk of myocardial infarction, and borderline isolated systolic hypertension predicts a possible but more modest increase in risk. These data add to the existing evidence that hypertension is a major cardiovascular risk factor and extend the findings to borderline isolated systolic hypertension.

Topics: Adult; Aged; Aged, 80 and over; Antioxidants; Aspirin; beta Carotene; Cardiovascular Diseases; Cerebrovascular Disorders; Cohort Studies; Confidence Intervals; Factor Analysis, Statistical; Humans; Hypertension; Male; Middle Aged; Multivariate Analysis; Myocardial Infarction; Physicians; Platelet Aggregation Inhibitors; Prevalence; Prospective Studies; Risk Factors; Systole; Time Factors; United States

Epidemiological data suggest that the intake of antioxidants such as alpha-tocopherol (vitamin E) and beta-carotene has an inverse correlation with the incidence of coronary heart disease. The results from clinical trials of antioxidant supplementation in people with known coronary heart disease are inconclusive.. We studied the frequency of major coronary events in 1862 men enrolled in the alpha-tocopherol beta-carotene Cancer Prevention Study (smokers aged between 50 and 69 years) who had a previous myocardial infarction. In this randomised, double-blind. placebo-controlled study, men had received dietary supplements of alpha-tocopherol (50 mg/day), beta-carotene (20 mg/day), both, or placebo. The median follow-up was 5.3 years. The endpoint of this substudy was the first major coronary event after randomisation. Analyses were by intention to treat.. 424 major coronary events (non-fatal myocardial infarction and fatal coronary heart disease) occurred during follow-up. There were no significant differences in the number of major coronary events between any supplementation group and the placebo group (alpha-tocopherol 94/466; beta-carotene 113/461; alpha-tocopherol and beta-carotene 123/497; placebo 94/438 [log-rank test, p = 0.25]). There were significantly more deaths from fatal coronary heart disease in the beta-carotene (74/461, multivariate-adjusted relative risk 1.75 [95% CI 1.16-2.64], p = 0.007) and combined alpha-tocopherol and beta-carotene groups (67/497, relative risk 1.58 [1.05-2.40], p = 0.03) than in the placebo group (39/438), but there was no significant increase in the alpha-tocopherol supplementation group (54/466, relative risk 1.33 [0.86-2.05], p = 0.20).. The proportion of major coronary events in men with a previous myocardial infarction who smoke was not decreased with either alpha-tocopherol or beta-carotene supplements. In fact, the risk of fatal coronary heart disease increased in the groups that received either beta-carotene or the combination of alpha-tocopherol and beta-carotene; there was a non-significant trend of increased deaths in the alpha-tocopherol group. We do not recommend the use of alpha-tocopherol or beta-carotene supplements in this group of patients.

Topics: Aged; Antioxidants; beta Carotene; Coronary Disease; Double-Blind Method; Finland; Follow-Up Studies; Humans; Male; Middle Aged; Multivariate Analysis; Myocardial Infarction; Placebos; Risk; Smoking; Vitamin E

In a randomized, double-blind, placebo-controlled trial, the effects of combined treatment with the antioxidant vitamins A (50,000 IU/day), vitamin C (1,000 mg/day), vitamin E (400 mg/day), and beta-carotene (25 mg/day) were compared for 28 days in 63 (intervention group) and 62 (placebo group) patients with suspected acute myocardial infarction. After treatment with antioxidants, the mean infarct size (creatine kinase and creatine kinase-MB gram equivalents) was significantly less in the antioxidant group than in the placebo group. Serum glutamic-oxaloacetic transaminase decreased by 45.6 IU/dl in the antioxidant group versus 25.8 IU/dl in the placebo group (p < 0.02). Cardiac enzyme lactate dehydrogenase increased slightly (88.6 IU/dl) in the antioxidant group compared with that in the placebo group (166.5 IU/dl) (p < 0.01). QRS score in the electrocardiogram was significantly less in the antioxidant than in the placebo group. The following levels increased in the antioxidant group versus the placebo group, respectively: plasma levels of vitamin E increased by 8.8 and 2.2 mumol/L (p < 0.01), vitamin C increased by 12.6 and 4.2 mumol/L (p < 0.01), beta-carotene increased by 0.28 and 0.06 mumol/L (p < 0.01), and vitamin A increased by 0.36 and 0.12 mumol/L (p < 0.01). Serum lipid peroxides decreased by 1.22 pmol/ml in antioxidant versus 0.22 pmol/ml in the placebo group (p < 0.01). Angina pectoris, total arrhythmias, and poor left ventricular function occurred less often in the antioxidant group. Cardiac end points were significantly less in the antioxidant group (20.6% vs 30.6%, respectively). These results suggest that combined treatment with antioxidant vitamins A, E, C, and beta-carotene in patients with recent acute myocardial infarction may be protective against cardiac necrosis and oxidative stress, and could be beneficial in preventing complications and cardiac event rate in such patients.

Topics: Adult; Antioxidants; Ascorbic Acid; Aspartate Aminotransferases; beta Carotene; Carotenoids; Creatine Kinase; Double-Blind Method; Drug Therapy, Combination; Electrocardiography; Female; Humans; L-Lactate Dehydrogenase; Lipid Peroxides; Male; Middle Aged; Myocardial Infarction; Oxidative Stress; Ventricular Function, Left; Vitamin A; Vitamin E; Vitamins

To determine whether a fat- and energy-reduced diet rich in antioxidant vitamins C and E, beta carotene, and soluble dietary fiber reduces free-radical stress and cardiac enzyme level and increases plasma ascorbic acid level 1 week after acute myocardial infarction.. Randomized, single blind, controlled study.. Primary- and secondary-care research center for patients with myocardial infarction.. All subjects with suspected acute myocardial infarction (n = 505) were considered for entry to the study. Subjects with definite or possible acute myocardial infarction and unstable angina (according to World Health Organization criteria) were assigned to either an intervention diet (n = 204) or a control diet (n = 202) within 48 hours of symptoms of infarction.. Intervention and control groups were advised to consume a fat-reduced, oil-substituted diet. The intervention group was also advised to eat more fruits, vegetable soup, pulses, and crushed almonds and walnuts mixed with skim milk.. Reduction in plasma lipid peroxide and lactate dehydrogenase cardiac enzyme levels, increase in plasma ascorbic acid level, and compliance with diet, especially with vitamin C intake as determined by chemical analysis.. A two-sample t test using one-way analysis of variance for comparison of data.. Plasma lipid peroxide level decreased significantly in the intervention group compared with the control group (0.59 pmol/L in the intervention group and 0.10 pmol/L in the control group; 95% confidence interval of difference = 0.19 to 0.83). Lactate dehydrogenase level increased less in the intervention group than in the control group (427.7 vs 561.2 U/L; confidence interval of difference = 82.9 to 184.7). Plasma ascorbic acid level increased more in the intervention group than in the control group (23.38 vs 7.95 mumol/L; confidence interval of difference = 12.85 to 26.13).. Consumption of an antioxidant-rich diet may reduce the plasma levels of lipid peroxide and cardiac enzyme and increase the plasma level of ascorbic acid. Antioxidant-rich foods may reduce myocardial necrosis and reperfusion injury induced by oxygen free radicals.

Topics: Analysis of Variance; Ascorbic Acid; beta Carotene; Carotenoids; Diet, Fat-Restricted; Dietary Fiber; Female; Free Radicals; Humans; L-Lactate Dehydrogenase; Lipid Peroxides; Male; Myocardial Infarction; Single-Blind Method; Vitamin A; Vitamin E; Vitamins

This study evaluated whether increased intake of fish oils (eicosapentaenoic and docosahexaenoic acids) might reduce the risk of coronary heart disease.. Observational and clinical studies have suggested that increased intake of fish oils, as reflected in plasma levels of fish oils, may reduce the risk of myocardial infarction.. A nested case-control study was conducted among the 14,916 participants in the Physicians' Health Study with a sample of plasma before randomization. Each participant with myocardial infarction occurring during the first 5 years of follow-up was matched by smoking status and age with a randomly chosen control participant who had not developed coronary heart disease.. Mean levels of fish oils (with 95% confidence interval [CI] for paired differences and p values) in case and control participants, expressed as percent of total fatty acids, were, for eicosapentaenoic acid, 0.26 versus 0.25 (95% CI -0.03 to 0.05, p = 0.70) in cholesterol esters and 0.56 versus 0.54 (95% CI -0.04 to 0.09, p = 0.44) in phospholipids, and for docosahexaenoic acid, 0.23 versus 0.24 (95% CI -0.07 to 0.04, p = 0.64) in cholesterol esters and 2.22 versus 2.14 (95% CI -0.10 to 0.27, p = 0.36) in phospholipids. Results adjusted for major cardiovascular risk factors showed a very similar lack of association between fish oil levels and the incidence of myocardial infarction.. These results indicate no beneficial effect of increased fish oil consumption on the incidence of a first myocardial infarction. However, the effect of very high levels of fish oils could not be evaluated.

Topics: Adjuvants, Immunologic; Aspirin; beta Carotene; Carotenoids; Case-Control Studies; Cholesterol Esters; Double-Blind Method; Fatty Acids, Omega-3; Fish Oils; Humans; Incidence; Logistic Models; Male; Middle Aged; Myocardial Infarction; Phospholipids; Physicians; Prospective Studies; Risk Factors

There is a growing interest in the function of antioxidants and free radicals and their roles in the development of arteriosclerosis. Oxidised LDL-cholesterol and polyunsaturated fatty acids may be involved in the development of arteriosclerotic lesions. The potential of antioxidant vitamins to prevent cardiovascular disease has been the subject of many studies. Up to now the results of different in vitro and in vivo studies remain controversial. For the first time, measurements of the concentrations of lipophilic antioxidants alpha-tocopherol (vitamin E) and beta-carotene (provitamin A) in fat-tissue have been used as an approach. This method is believed to provide an average of the antioxidant intake over a longer period of time and probably reflects steady-state levels rather than intake. A case-control study was conducted using first occurrence of myocardial infarction in men as disease endpoint. In the swiss part of EURAMIC, cases were recruited in collaboration with the hospitals of Zurich. Controls were chosen randomly from the population register of Zurich. Fifty-seven male cases and 74 male controls were enrolled in the protocol. The classical risk factors showed the expected pattern. Levels for beta-carotene were significantly lower in the patient group (0.36 microgram/g biopsy versus 0.52 microgram/g biopsy in controls, p < or = 0.02). In contrast, levels for alpha-tocopherol were similar in both groups (237.5 micrograms/g biopsy in patients and 233.4 micrograms/g biopsy in controls). The Swiss alpha-tocopherol levels were the highest of all participating centres. Analyses of the questionnaires showed significantly higher consumption of vitamin C supplements in the control group.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Adipose Tissue; Adult; Aged; Anthropometry; Antioxidants; beta Carotene; Carotenoids; Case-Control Studies; Humans; Life Style; Lipids; Male; Middle Aged; Myocardial Infarction; Vitamin E

Epidemiological studies have not given sufficient evidence yet for the role of antioxidant nutrients in the prevention of cardiovascular disease. As regards cancer, an inverse association between beta-carotene intake and specific types of cancer, especially lung cancer, has been shown. For other cancer sites and other antioxidants, the association is less clear. The EURAMIC Study, an EC Concerted Action, is a case-control study conducted in 11 countries, in which the combined effect of vitamin E, beta-carotene and selenium, in relation to fatty acid intake, will be examined. The disease endpoints are acute myocardial infarction and early-stage breast cancer. The broad range of antioxidant intake, the use of biomarkers of exposure, and the analysis of pooled data will allow an estimate of the strength of the putative beneficial effect. In this paper the background and design of the study will be introduced.

Topics: Aged; Antioxidants; beta Carotene; Breast Neoplasms; Carotenoids; Case-Control Studies; Europe; Female; Humans; Israel; Male; Middle Aged; Myocardial Infarction; Nutritional Physiological Phenomena; Research Design; Selenium; Vitamin E

To evaluate the efficacy of low-dose aspirin in the primary prevention of myocardial infarction among patients with chronic stable angina.. A randomized, double-blind, trial.. The study included 333 men with baseline chronic stable angina but with no previous history of myocardial infarction, stroke, or transient ischemic attack who were enrolled in the Physicians' Health Study, a trial of aspirin among 22,071 male physicians.. Patients were randomly assigned to receive alternate-day aspirin therapy (325 mg) or placebo and were followed for an average of 60.2 months for the occurrence of myocardial infarction, stroke, or cardiovascular death.. During follow-up, 27 patients had confirmed myocardial infarctions; 7 were among the 178 patients with chronic stable angina who received aspirin therapy and 20 were among the 155 patients who received placebo (relative risk, 0.30; 95% CI, 0.14 to 0.63; P = 0.003). While simultaneously controlling for other cardiovascular risk factors in a proportional hazards model, an overall 87% risk reduction was calculated (relative risk, 0.13; CI, 0.04 to 0.42; P less than 0.001). For the subgroup of patients with chronic stable angina but no previous coronary bypass surgery or coronary angioplasty, an almost identical reduction in the risk for myocardial infarction was found (relative risk, 0.14; CI, 0.04 to 0.56; P = 0.006). Of 13 strokes, 11 occurred in the aspirin group and 2 in the placebo group (relative risk, 5.4; CI, 1.3 to 22.1; P = 0.02). No stroke was fatal, but 4 produced some long-term impairment of function. One stroke, in the aspirin group, was hemorrhagic.. Our data indicated that alternate-day aspirin therapy greatly reduced the risk for first myocardial infarction among patients with chronic stable angina, a group of patients at high risk for cardiovascular death (P less than 0.001). Although our results for stroke were based on small numbers, they suggested an apparent increase in frequency of stroke with aspirin therapy; this finding requires confirmation in randomized trials of adequate sample size.

Topics: Adult; Aged; Aged, 80 and over; Angina Pectoris; Aspirin; beta Carotene; Cardiovascular Diseases; Carotenoids; Cerebrovascular Disorders; Chronic Disease; Double-Blind Method; Drug Administration Schedule; Drug Therapy, Combination; Humans; Male; Middle Aged; Myocardial Infarction; Risk; Statistics as Topic

Topics: Adult; Aged; Aspirin; beta Carotene; Cardiovascular Diseases; Carotenoids; Cerebrovascular Disorders; Clinical Trials as Topic; Double-Blind Method; Humans; Male; Middle Aged; Myocardial Infarction; Neoplasms; Random Allocation

The causal association between circulating β-carotene concentrations and cardiovascular disease (CVD) remains controversial. We conducted a Mendelian randomization study to explore the effects of β-carotene on various cardiovascular diseases, including myocardial infarction, atrial fibrillation, heart failure, and stroke. Three single nucleotide polymorphisms (SNPs) associated with the β-carotene levels were obtained by searching published data and used as instrumental variables. Genetic association estimates for 4 CVDs (including myocardial infarction, atrial fibrillation, heart failure, and stroke) in the primary analysis, blood pressure and serum lipids (high-density lipoprotein [HDL] cholesterol, LDL cholesterol, and triglycerides) in the secondary analysis were obtained from large-scale genome-wide association studies (GWASs). We applied inverse variance-weighted as the primary analysis method, and 3 others were used to verify as sensitivity analysis. Genetically predicted circulating β-carotene levels (natural log-transformed, µg/L) were positively associated with myocardial infarction (odds ratio [OR] 1.10, 95% confidence interval [CI] 1.02-1.18, P = .011) after Bonferroni correction. No evidence supported the causal effect of β-carotene on atrial fibrillation (OR 1.02, 95% CI 0.96-1.09, P = .464), heart failure (OR 1.07, 95% CI 0.97-1.19, P = .187), stroke (OR 1.03, 95% CI 0.93-1.15, P = .540), blood pressure (P > .372) and serum lipids (P > .239). Sensitivity analysis produced consistent results. This study provides evidence for a causal relationship between circulating β-carotene and myocardial infarction. These findings have important implications for understanding the role of β-carotene in CVD and may inform dietary recommendations and intervention strategies for preventing myocardial infarction.

Topics: Atrial Fibrillation; beta Carotene; Cardiovascular Diseases; Cholesterol, HDL; Genome-Wide Association Study; Heart Failure; Humans; Mendelian Randomization Analysis; Myocardial Infarction; Polymorphism, Single Nucleotide; Stroke; Triglycerides

β-carotene (BC), a lipid-soluble tetraterpene precursor to vitamin A, widely distributed in plants, including many used in human diet, has well-known health-enhancing properties, including reducing risk of and treatment for certain diseases. Nevertheless, BC may also act to promote disease through the activity of BC derivatives that form in the presence of external toxicants such as cigarette smoke and endogenously-produced reactive oxygen species. The present investigation evaluates the dose-dependent cardioprotective and possibly harmful properties of BC in a rat model. Adult male rats were gavage-fed BC for 4 weeks, at dosages of either 0, 30 or 150 mg/kg/day. Then, hearts excised from the animals were mounted in a "working heart" apparatus and subjected to 30 min of global ischemia, followed by 120 min of reperfusion. A panel of cardiac functional evaluations was conducted on each heart. Infarct size and total antioxidant capacity of the myocardium were assessed. Heart tissue content of heme oxygenase-1 (HO-1) by Western blot analysis; and potential direct cytotoxic effects of BC by MTT assay were evaluated. Hearts taken from rats receiving 30 mg/kg/day BC exhibited significantly improved heart function at lower reperfusion times, but lost this protection at higher BC dosage and longer reperfusion times. Myocardial HO-1 content was significantly elevated dose-responsively to both BC dosage. Finally, in vitro evaluation of BC on H9c2 cells showed that the agent significantly improved vitality of these cells in a dose range of 2.5-10 μM. Although data presented here do not allow for a comprehensive mechanistic explanation for reduced cardioprotection at high dose BC, it is speculated that since Fe2+ produced as a metabolite of HO-1 activity, may determine whether BC acts as an antioxidant or prooxidant agent, the strong induction of this enzyme in response to ischemia/reperfusion-induced oxidative stress may account for the high-dose BC loss of cardioprotection.

Topics: Animals; Antioxidants; beta Carotene; Cardiotonic Agents; Heart; Heme Oxygenase-1; Male; Myocardial Infarction; Myocardial Reperfusion Injury; Myocardium; Oxidative Stress; Rats

Topics: Aspirin; beta Carotene; Controlled Clinical Trials as Topic; Dose-Response Relationship, Drug; Health Promotion; Humans; Minnesota; Myocardial Infarction; Neoplasms; Self Medication; Stroke

Previous studies have shown that high intake or concentrations of serum carotenoids may protect against acute myocardial infarction (AMI). The role of carotenoids on the risk of AMI remains inconsistent. The aim of the present study was to examine if serum concentrations of major carotenoids are related to AMI in men.. The study population consisted of 1031 Finnish men aged 46-65 years in the Kuopio Ischaemic Heart Disease Risk Factor (KIHD) cohort. Serum concentrations of carotenoids, retinol and α-tocopherol were measured by high-performance liquid chromatography. The association between the serum concentrations of lycopene α-carotene and β-carotene and the risk of AMI was studied by using the Cox proportional hazard models.. A total of 194 incident AMI cases occurred during an average of 11.5 follow-up years. After adjusting for potential confounders, the risk of AMI for men in the lowest tertile of serum concentrations compared with men in the highest tertile was 1.55 (95% CI 1.05- 2.30; P = 0.028) for lycopene and 1.60 (95% CI 1.09-2.35; P = 0.017) for β-carotene.. This cross-sectional study shows that low serum lycopene and β-carotene concentrations may increase the risk of AMI in men.

Topics: Aged; beta Carotene; Carotenoids; Chromatography, High Pressure Liquid; Cross-Sectional Studies; Finland; Follow-Up Studies; Humans; Incidence; Lycopene; Male; Middle Aged; Myocardial Infarction; Proportional Hazards Models; Risk Factors; Surveys and Questionnaires

Modification of low-density lipoprotein due to oxidative stress is essential in the development of coronary atherosclerosis. Data of specific carotenoids except β-carotene on cardioprotective effects in humans are limited.. This study examined the associations between plasma concentrations of specific carotenoids and incidence of acute myocardial infarction. The study included 280 incident cases of acute myocardial infarction and 560 matched controls nested within the Singapore Chinese Health Study, a prospective cohort of 63,257 Chinese men and women aged 45-74 years old enrolled in 1993-1998 in Singapore. Retinol and carotenoids in prediagnostic plasma were quantified using high-performance liquid chromatography. High levels of plasma β-cryptoxanthin and lutein were associated with decreased risk of acute myocardial infarction after adjustment for multiple risk factors for coronary heart disease. For β-cryptoxanthin, the odds ratio (95% confidence interval) for the highest (Q5) versus the lowest (Q1) quintile was 0.67 (0.37-1.21) (P for trend=0.03). For lutein, the odds ratios (95% confidence intervals) for the combined Q2-Q3 and the combined Q4-Q5 versus Q1 were 0.71 (0.45-1.12) and 0.58 (0.35-0.94) respectively (P for trend=0.03). There was no statistically significant association between other carotenoids or retinol and risk of acute myocardial infarction.. High plasma levels of β-cryptoxanthin and lutein were associated with decreased risk of acute myocardial infarction. The findings of this study support a cardioprotective role of these two carotenoids in humans.

Topics: Acute Disease; Aged; Asian People; beta Carotene; Carotenoids; Case-Control Studies; Cholesterol, HDL; Cholesterol, LDL; Confidence Intervals; Female; Humans; Lutein; Male; Middle Aged; Myocardial Infarction; Odds Ratio; Prospective Studies; Risk Factors; Singapore; Triglycerides; Vitamin A

The mechanisms involved in the biggest remodeling caused by the post-infarct beta-carotene are unknown.. To analyze the role of lipoperoxidation in the ventricular remodeling after infarct of the myocardium in rats supplemented with beta-carotene.. Rats were infarcted and divided into two groups: C (control) and BC (500mg/kg/regimen). After six months, echocardiogram and biochemical evaluation were performed. The t test was used, with 5% significance.. The animals from BC group presented highest means of the diastolic (C = 1.57 +/- 0.4 mm(2)/g, BC = 2.09 +/- 0.3 mm(2)/g; p < 0.001) and systolic (C = 1.05 +/- 0.3 mm(2)/g, BC = 1.61 +/- 0.3 mm(2)/g; p < 0.001) areas of LV, which were adapted according to the rat's body weight. The systolic function of LV, evaluated by the area variation fraction, was lower in the animals supplemented with beta-carotene (C = 31.9 +/- 9.3%, BC = 23.6 +/- 5.1%; p = 0.006). The animals supplemented with beta-carotene presented higher values of the E/A relation (C = 2.7 +/- 2.5, BC = 5.1 +/- 2.8; p = 0.036). No differences were found between the groups concerning the cardiac levels of the GSH (C = 21 +/- 8 nmol/mg of protein, BC = 37 +/- 15 nmol/mg of protein; p = 0.086), GSSG (C = 0.4 (0.3-0.5) nmol/g of protein, BC = 0.8 (0.4-1.0; p = 0.19) of protein; p = 0.246) and lipoperoxides (C = 0.4 +/- 0.2 nmol/mg of tissue, BC = 0.2 +/- 0.1 nmol/mg of tissue; p = 0.086).. The highest remodeling in infarcted rats supplemented with beta-carotene does not depend on the lipoperoxidation.

Topics: Animals; Antioxidants; beta Carotene; Disease Models, Animal; Drug Evaluation, Preclinical; Lipid Peroxidation; Male; Myocardial Infarction; Random Allocation; Rats; Rats, Wistar; Ventricular Function; Ventricular Remodeling; Vitamins

To analyze the effects of beta-carotene on the ventricular remodeling process following myocardial infarction (MI) in rats exposed to cigarette smoke.. After acute myocardial infarction (AMI), the animals were divided into four groups: 1) Group C, 24 animals that were given standard diet; 2) Group BC, 26 animals that were given beta-carotene; 3) Group ECS, 26 animals that were given standard diet and were exposed to cigarette smoke; and 4) Group BC+ECS, 20 animals that were given beta-carotene and were exposed to cigarette smoke. After six months, a morphofunctional study was performed. We used a 5% significance level.. As regards diastolic areas (DA) and systolic areas (SA), the values for the BC group were higher than those for the C group. If DA/body weight (BW) and SA/BW are considered, the values for group BC+ECS were higher than the values for group C. As regards the fractional area change, we observed significant differences between ECS (lower values) and C (higher values) and between BC (lower values) and C (higher values). Differences between groups regarding infarction size were not observed. The ECS group presented higher values for myocyte cross-section area (MCA) than control animals. Additionally, the BC+ECS group presented higher MCA values than the BC, ECS and C groups.. After myocardial infarction, smoking and beta-carotene intensified the heart remodeling process; harmful effects of the remodeling process were heightened when the two treatments were used in conjunction.

Topics: Analysis of Variance; Animals; Antioxidants; beta Carotene; Diet; Dietary Supplements; Echocardiography; Heart Rate; Inhalation Exposure; Male; Models, Animal; Myocardial Infarction; Myocardium; Rats; Rats, Wistar; Smoking; Ventricular Remodeling

We studied the effects of beta-carotene (BC) on ventricular remodeling after myocardial infarction.. Myocardial infarction was induced in Wistar rats that were then treated with a BC diet (500 mg/kg of diet per day; MI-BC; n = 27) or a regular diet (MI; n = 27). Hearts were analyzed in vivo and in vitro after 6 mo.. BC caused decreased left ventricular wall thickness (MI = 1.49 +/- 0.3 mm, MI-BC = 1.23 +/- 0.2 mm, P = 0.027) and increased diastolic (MI = 0.83 +/- 0.15 cm2, MI-BC = 0.98 +/- 0.14 cm2, P = 0.020) and systolic (MI = 0.56 +/- 0.12 cm2, MI-BC = 0.75 +/- 0.13 cm2, P = 0.002) left ventricular chamber areas. With respect to systolic function, the BC group presented less change in fractional area than did controls (MI = 32.35 +/- 6.67, MI-BC = 23.77 +/- 6.06, P = 0.004). There was no difference in transmitral diastolic flow velocities between groups. In vitro results showed decreased maximal isovolumetric systolic pressure (MI = 125.5 +/- 24.1 mmHg, MI-BC = 95.2 +/- 28.4 mmHg, P = 0.019) and increased interstitial myocardial collagen concentration (MI = 3.3 +/- 1.2%, MI-BC = 5.8 +/- 1.7%, P = 0.004) in BC-treated animals. Infarct sizes were similar between groups (MI = 45.0 +/- 6.6%, MI-BC = 48.0 +/- 5.8%, P = 0.246).. Taken together, these data suggest that BC has adverse effects on ventricular remodeling after myocardial infarction.

Topics: Animals; Antioxidants; beta Carotene; Dietary Supplements; Heart; Male; Myocardial Infarction; Myocardium; Random Allocation; Rats; Rats, Wistar; Treatment Outcome; Ventricular Function; Ventricular Remodeling

In the current study, the improved oral bioavailability of a synthetic astaxanthin derivative (Cardax; disodium disuccinate astaxanthin) was utilized to evaluate its potential effects as a cardioprotective agent after 7-day subchronic oral administration as a feed supplement to Sprague-Dawley rats. Animals received one of two concentrations of Cardax in feed (0.1 and 0.4%; approximately 125 and 500 mg/kg/day, respectively) or control feed without drug for 7 days prior to the infarct study carried out on day 8. Thirty minutes of occlusion of the left anterior descending (LAD) coronary artery was followed by 2 h of reperfusion prior to sacrifice, a regimen which resulted in a mean infarct size (IS) as a percentage (%) of the area at risk (AAR; IS/AAR,%) of 61 +/- 1.8%. The AAR was quantified by Patent blue dye injection, and IS was determined by triphenyltetrazolium chloride (TTC) staining. Cardax at 0.1 and 0.4% in feed for 7 days resulted in a significant mean reduction in IS/AAR,% to 45 +/- 2.0% (26% salvage) and 39 +/- 1.5% (36% salvage), respectively. Myocardial levels of free astaxanthin achieved after 7-day supplementation at each of the two concentrations (400 +/- 65 nM and 1634 +/- 90 nM, respectively) demonstrated excellent solid-tissue target organ loading after oral supplementation. Parallel trends in reduction of plasma levels of multiple lipid peroxidation products with disodium disuccinate astaxanthin supplementation were observed, consistent with the documented in vitro antioxidant mechanism of action. These results extend the potential utility of this compound for cardioprotection to the elective human cardiovascular patient population, for which 7-day oral pre-treatment (as with statins) provides significant reductions in induced periprocedural infarct size.

Topics: Administration, Oral; Animal Feed; Animals; beta Carotene; Biological Availability; Cardiotonic Agents; Coronary Vessels; Dietary Supplements; Lipid Peroxidation; Myocardial Infarction; Myocardial Reperfusion; Oxidative Stress; Rats; Rats, Sprague-Dawley; Succinates; Xanthophylls

Serum levels of vitamin E (VE), beta-carotene (BC) and vitamin C (VC) were determined in 50 patients with the first acute myocardial infarction (AMI) before starting thrombolytical treatment. VE and BC were determined by HPLC, VC spectrophotometrically. The reperfused patients were divided according to vitamin concentrations into four groups. The lowest quartile was compared with the rest of the studied population (VE: group with high (H)>15.6 microM>group with low (L), BC: H>0.07 microM>L, VC: H>25 microM>L) in the following parameters: extent of myocardial damage (area under the curves of troponin I, CK-MB during 48 h), arrhythmia and congestive heart failure occurrence, size of ejection fraction, positivity of ventricular late potentials. No significant differences between groups H and L for either VE, BC or VC were found (P 0.05). As no correlation between serum concentrations of vitamins E, C and beta-carotene and the extent and clinical course of AMI was found, the actual vitamin concentrations may be important for prevention of ischemic heart a disease, but they do not play a decisive role in the acute phase of myocardial infarction in humans.

Topics: Antioxidants; Ascorbic Acid; beta Carotene; Female; Humans; Male; Middle Aged; Myocardial Infarction; Vitamin E; Vitamins

Carotenoids are a naturally occurring group of compounds that possess antioxidant properties. Most natural carotenoids display poor aqueous solubility and tend to form aggregates in solution. Disodium disuccinate astaxanthin (DDA; Cardax) is a water-dispersible synthetic carotenoid that rapidly and preferentially associates with serum albumin, thereby preventing the formation of supramolecular complexes and facilitating its efficacy after parenteral administration. This study investigated the ability of DDA to reduce inflammation and myocardial injury in a rabbit model of ischemia/reperfusion. DDA (50 mg/kg/day) or saline was administered i.v. for 4 consecutive days before the initiation of the protocol for induction of myocardial ischemia/reperfusion. On the 5th day, rabbits underwent 30 min of coronary artery occlusion, followed by a 3-h reperfusion period. Myocardial infarct size, as a percentage of the area at risk, was calculated for both groups. Infarct size was 52.5 +/- 7.5% in the vehicle-treated (n = 9) and 25.8 +/- 4.7% in the DDA-treated (n = 9) animals (p < 0.01 versus vehicle; mean myocardial salvage = 51%). To evaluate the anti-inflammatory effects of DDA, complement activity was assessed at the end of reperfusion using a red blood cell lysis assay. DDA administration significantly reduced (p < 0.01) the activation of the complement system in the serum. The current results, coupled with the well established antioxidant ability of carotenoids, suggest that the mechanism(s) of action by which DDA reduces the tissue damage associated with reperfusion injury may include both antioxidant and anticomplement components.

Topics: Adjuvants, Immunologic; Animals; beta Carotene; C-Reactive Protein; Complement Activation; Complement Inactivator Proteins; Complement Membrane Attack Complex; Erythrocytes; Fluorescent Antibody Technique; Hemodynamics; Hemolysis; Male; Myocardial Infarction; Myocardial Reperfusion Injury; Myocardium; Rabbits; Tetrazolium Salts; Thiazoles; Tissue Distribution; Troponin I; Xanthophylls

Previous results from our laboratory have shown that a novel carotenoid derivative (disodium disuccinate astaxanthin; Cardax) produced dose-related reductions in myocardial infarct size (IS) in Sprague-Dawley rats when it was administered at any of three doses (25, 50 and 75 mg/kg, iv) on four consecutive days, followed by the acute infarct size study on day 5. Maximum salvage occurred at the highest dose (75 mg/kg) tested, and was shown as a 56% reduction in IS. In the present follow-up study, we used a more relevant large animal model, the dog, and looked at the effect of administering Cardax iv either acutely 2 h prior to occlusion (N = 8) or for 4 days at 50 mg/kg iv as previously done in the rat model (N = 6). The results were compared to a saline vehicle-treated group (N = 10). In all groups, dogs were subjected to 60 min of left anterior descending (LAD) coronary artery occlusion and 3 h of reperfusion. IS was determined using a triphenyltetrazolium chloride (TTZ) histochemical stain and was expressed as a percent of the area at risk (IS/AAR). IS/AAR was 20.9 +/- 1.6 % (mean +/- S.E.M.) in controls and was reduced to 11.0 +/- 1.7% (47.3% salvage; p < 0.01) in dogs treated only once iv at 2 h prior to occlusion, and 6.6 +/- 2.8% (68.4% salvage; p < 0.001) in dogs treated for 4 days. In the chronic treatment group, two of the three dogs with plasma concentrations of non-esterified astaxanthin above 1 microM had 0% IS/AAR (100% cardioprotection). These results suggest that Cardax has marked cardioprotective properties in both rodents and canines. Thus, Cardax may be a novel and powerful new means to prevent myocardial injury and/or necrosis associated with elective and/or urgent cardiac surgical interventions such as coronary angioplasty and stenting, as well as coronary artery bypass surgery (CABG).

Topics: Animals; beta Carotene; Cardiotonic Agents; Dogs; Heart; Myocardial Infarction; Myocardial Reperfusion; Myocardial Reperfusion Injury; Succinates; Xanthophylls

The objective of this study was to investigate the effects of exposure to tobacco smoke (ETS) in rats that were or were not supplemented with dietary beta-carotene (BC), on ventricular remodeling and survival after myocardial infarction (MI). Rats (n = 189) were allocated to 4 groups: the control group, n = 45; group BC administered 500 mg/kg diet, n = 49, BC supplemented rats; group ETS, n = 55, rats exposed to tobacco smoke; and group BC+ETS, n = 40. Wistar rats weighing 100 g were administered one of the treatments until they weighed 200 to 250 g (approximately 5 wk). The ETS rats were exposed to cigarette smoke for 30 min 4 times/d, in a chamber connected to a smoking device. After reaching a weight of 200-250 g, rats were subjected to experimental MI (coronary artery occlusion) and mortality rates were determined over the next 105 d. In addition, echocardiographic, isolated heart, morphometrical, and biochemical studies were performed. Mortality data were tested using Kaplan-Meyer curves and other data by 2-way ANOVA. Survival rates were greater in the ETS group (58.2%) than in the control (33.3%) (P = 0.001) and BC+ETS rats (30.0%) (P = 0.007). The groups did not differ in the other comparisons. Left ventricular end-diastolic diameter normalized to body weight was greater and maximal systolic pressures were lower in the ETS groups than in non-ETS groups. Previous exposure to tobacco smoke induced a process of cardiac remodeling after MI. There is a paradoxical protector effect with tobacco smoke exposure, characterized by lower mortality, which is offset by BC supplementation.

Topics: Animals; beta Carotene; Diet; Echocardiography; Heart; In Vitro Techniques; Male; Myocardial Infarction; Myocardium; Nicotiana; Rats; Rats, Wistar; Smoke; Survival Analysis; Ventricular Remodeling

Cardioprotection in humans by carotenoids has been inferred from observational and epidemiologic studies, however, direct studies of cardioprotection and myocardial salvage by carotenoids are lacking. In the current study, intravenous (I.V.) pre-treatment with a novel carotenoid derivative (disodium disuccinate astaxanthin; Cardax) was evaluated as a myocardial salvage agent in a Sprague-Dawley rat infarct model. Animals were dosed once per day I.V. by tail vein injection for 4 days at one of 3 doses (25, 50, and 75 mg/kg) prior to the infarct study carried out on day 5. The results were compared with control animals treated with saline vehicle. Thirty (30) minutes of occlusion of the left anterior descending (LAD) coronary artery was followed by 2 hours of reperfusion prior to sacrifice, a regimen which resulted in a mean infarct size (IS) as a percent (%) of the area at risk (AAR) of 59 +/- 3%. Area at risk was quantified by Patent blue dye injection, and infarct size (IS) was determined by triphenyltetrazolium chloride (TTC) staining. Cardax at 50 and 75 mg/kg for 4 days resulted in a significant mean reduction in IS/AAR to 35 +/- 3% (41% salvage) and 26 +/- 2% (56% salvage), respectively. Infarct size and myocardial salvage were significantly, and linearly, correlated with plasma levels of non-esterified, free astaxanthin at the end of reperfusion. These results suggest that parenteral Cardax may find utility in those clinical applications where pre-treatment of patients at risk for myocardial infarction is performed.

Topics: Analysis of Variance; Animals; beta Carotene; Cardiotonic Agents; Dose-Response Relationship, Drug; Injections, Intravenous; Myocardial Infarction; Myocardial Ischemia; Myocardial Reperfusion; Rats; Rats, Sprague-Dawley; Succinates; Tetrazolium Salts; Xanthophylls

No-reflow phenomenon is observed in approximately one-third of patients after percutaneous coronary intervention (PCI) for acute myocardial infarction (AMI), and is associated with poor functional and clinical outcomes. On the other hand, the formation of free radicals in vasculature exerts deleterious effects on coronary microcirculation.. We hypothesized that redox state in coronary circulation may play a crucial role in no-reflow phenomenon in AMI.. Consecutive 26 patients with first AMI who underwent primary PCI < 24 h after onset were enrolled. Before PCI, blood samples were obtained from coronary sinus to measure plasma or serum antioxidative vitamins (vitamin C, vitamin E, and beta-carotene) and antioxidative enzymes (extracellular glutathione peroxidase [GPX], superoxide dismutase, and catalase). After PCI, the corrected Thrombolysis In Myocardial Infarction (TIMI) frame count (CTFC) was measured in the target vessel. Patients with TIMI < or = 2 flow despite an optimal PCI result were designated as no-reflow group (Group NR, n = 6) and the others as reflow group (Group R, n = 20).. Levels of vitamin C, vitamin E, and GPX before PCI were significantly lower in Group NR than in Group R. The CTFC correlated inversely with levels of vitamin C, vitamin E, and GPX (p < 0.05).. Depletion of antioxidants is associated with no-reflow phenomenon in AMI. These findings strongly suggest that the redox state in coronary circulation plays an important role in the pathogenesis of no-reflow phenomenon.

Topics: Aged; Aged, 80 and over; Antioxidants; Ascorbic Acid; beta Carotene; Catalase; Coronary Circulation; Female; Glutathione Peroxidase; Humans; Male; Middle Aged; Myocardial Infarction; Myocardial Reperfusion; Oxidation-Reduction; Statistics, Nonparametric; Superoxide Dismutase; Vitamin E

Lipid peroxidation and derived oxidized products are being intensively investigated because of their potential to cause injury and because of their pathogenic role in several diseases. The view that an excess of lipid peroxidation products is present and is relevant in the pathogenesis of cardiogenic shock-induced damage has still not received definitive support.. To evaluate the extent of lipid peroxidation, the status of enzymatic and nonenzymatic antioxidants in patients with cardiogenic shock that complicate acute myocardial infarction (AMI) and to compare with normal subjects.. Compared with normal subjects, cardiogenic shock patients had higher malondialdehyde, conjugated dienes and reduced activities of erythrocyte antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and lower concentrations of reduced glutathione (GSH) in erythrocyte and in plasma GSH, vitamin C, vitamin E and in beta-carotene.. Cardiogenic shock is associated with greater than normal lipid peroxidation and with an imbalance in antioxidants' status. These results indicate that low activities of SOD, CAT, GPx and low concentrations of GSH, vitamin C, vitamin E and beta-carotene in the circulation of patients with cardiogenic shock complicating AMI may be due to increased utilization to scavenge lipid peroxides. Decrease in plasma concentrations of GSH, vitamin E and beta-carotene seems to be responsible for the elevation of lipid peroxidation in cardiogenic shock complicating AMI compared with MI.

Topics: Antioxidants; Ascorbic Acid; beta Carotene; Blood Pressure; Catalase; Female; Glutathione; Glutathione Peroxidase; Heart Rate; Humans; Male; Middle Aged; Myocardial Infarction; Oxidative Stress; Shock, Cardiogenic; Superoxide Dismutase; Thiobarbituric Acid Reactive Substances; Vitamin E

Increased intake of carotenoids and vitamin E may protect against myocardial infarction (MI). However, prospective data on blood levels of carotenoids other than beta-carotene and vitamin E (tocopherol) and risk of MI are sparse.. We conducted a prospective, nested case-control analysis among male physicians without prior history of cardiovascular disease who were followed for up to 13 years in the Physicians' Health Study. Samples from 531 physicians diagnosed with MI were analyzed together with samples from paired control subjects, matched for age and smoking, for 5 major carotenoids (alpha- and beta-carotene, beta-cryptoxanthin, lutein, and lycopene), retinol, and alpha- and gamma-tocopherol. Overall, we found no evidence for a protective effect against MI for higher baseline plasma levels of retinol or any of the carotenoids measured. Among current and former smokers but not among never-smokers, higher baseline plasma levels of beta-carotene tended to be associated with lower risk (P for interaction=0.02). Men with higher plasma levels of gamma-tocopherol tended to have an increased risk of MI (P for trend=0.01).. These prospective data do not support an overall protective relation between plasma carotenoids or tocopherols and future MI risk among men without a history of prior cardiovascular disease.

Topics: Adult; Aged; Aged, 80 and over; alpha-Tocopherol; beta Carotene; Carotenoids; Case-Control Studies; Comorbidity; Cryptoxanthins; Follow-Up Studies; gamma-Tocopherol; Humans; Lutein; Lycopene; Male; Middle Aged; Myocardial Infarction; Physicians; Prospective Studies; Risk; Risk Assessment; Smoking; Tocopherols; United States; Vitamin A; Xanthophylls

Flavonols and flavones are antioxidant polyphenolic compounds found in tea, vegetables, fruits, and wine. In experimental studies they have been effective free radical scavengers, metal chelators, and antithrombotic agents. In the few epidemiologic studies of these agents, some have suggested an inverse association between intake of flavonols and flavones and the risk of cardiovascular disease. Our study population comprised 25,372 male smokers, 50-69 years of age, with no previous myocardial infarction. They were participants of the Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study, which was a randomized, double-blind, placebo-controlled trial with daily supplementation of alpha-tocopherol (50 mg per day) and/or beta-carotene (20 mg per day). The men completed a validated dietary questionnaire at baseline. After 6.1 years of follow-up, there were 1,122 nonfatal myocardial infarctions and 815 coronary deaths. In the multivariate model, the relative risk of nonfatal myocardial infarction was 0.77 (95% confidence interval = 0.64-0.93) among men in the highest (median 18 mg per day) compared with the lowest (median 4 mg per day) quintile of flavonol and flavone intake. The respective relative risk for coronary death was 0.89 (95% confidence interval = 0.71-1.11). Thus, intake of flavonols and flavones was inversely associated with nonfatal myocardial infarction, whereas there was a weaker association with coronary death.

Topics: Aged; Antioxidants; beta Carotene; Cohort Studies; Double-Blind Method; Finland; Flavonoids; Flavonols; Humans; Male; Middle Aged; Myocardial Infarction; Risk Factors; Smoking; Vitamin E

The consequences of increased oxidative stress, measured as the level of malondialdehyde (MDA) during ischemia/reperfusion, were studied in 48 patients in the acute phase of myocardial infarction (AMI) and a control group (21 blood donors). The serum levels of alpha-tocopherol and beta-carotene were followed. Immediately after the treatment onset the level of alpha-tocopherol started to decrease, reaching a plateau after 24 h. The consumption of beta-carotene was delayed by 90 min. Steady decline was detected during the whole time interval studied (48 h). Glutathione peroxidase (GPx) activity, as a representative of antioxidant enzymes, was estimated in whole blood. The influx of oxygenated blood was accompanied by a stimulation of GPx activity, which reached its maximum at the time of completed reperfusion. When comparing the AMI patients with the control group, the levels of MDA were found significantly increased, which indicates that oxidative stress is already increased during ischemia. Lower antioxidant levels found in the patients might either already be the result of vitamin consumption during ischemia or be a manifestation of their susceptibility to AMI. Monitored consumption of alpha-tocopherol and beta-carotene during reperfusion indicated that in the case of patients, whose level of antioxidant vitamins is below the threshold limit, a further substantial decrease of antioxidant vitamins during reperfusion could enhance the oxidative damage of the myocardium.

Topics: Aged; alpha-Tocopherol; Antioxidants; beta Carotene; Female; Glutathione Peroxidase; Humans; Male; Malondialdehyde; Middle Aged; Myocardial Infarction; Myocardial Reperfusion Injury; Oxidative Stress

A method is described for evaluation of fat-soluble vitamin in human adipose tissue with the aim to obtain, accurately and within the shortest analysis time, a time-integrated measure of exposure to vitamins from the diet. Fat tissue was deproteinized with ethanol and extracted with n-hexane. Normal-phase HPLC was performed in a Lichrosorb Si60 column with a gradient of n-hexane-2-propanol at 1 ml/min. Detection was accomplished using a diode-array system (for retinol and beta-carotene) in series with a fluorescence detector (alpha-tocopherol). The method was validated and applied to human adipose tissue in a total of 140 subjects. The mean contents found were 0.43, 0.84, 240.3 microg/g for retinol, beta-carotene and alpha-tocopherol, respectively. The method is sensitive enough for detecting the compounds in 1.6 mg of adipose tissue considering the lowest concentration found.

Topics: Adipose Tissue; alpha-Tocopherol; beta Carotene; Chromatography, High Pressure Liquid; Diet; Humans; Myocardial Infarction; Portugal; Reproducibility of Results; Risk Factors; Sensitivity and Specificity; Spectrometry, Fluorescence; Spectrophotometry, Ultraviolet; Surveys and Questionnaires; Vitamin A

Epidemiologic studies have shown dietary antioxidants to be inversely correlated with ischemic heart disease.. We investigated whether dietary beta-carotene, vitamin C, and vitamin E were related to the risk of myocardial infarction (MI) in an elderly population.. The study sample consisted of 4802 participants of the Rotterdam Study aged 55-95 y who were free of MI at baseline and for whom dietary data assessed by a semiquantitative food frequency questionnaire were available. During a 4-y follow-up period, 124 subjects had an MI. The association between energy-adjusted beta-carotene, vitamin C, and vitamin E intakes and risk of MI was examined by multivariate logistic regression.. Risk of MI for the highest compared with the lowest tertile of beta-carotene intake was 0.55 (95% CI: 0.34, 0.83; P for trend = 0.013), adjusted for age, sex, body mass index, pack-years, income, education, alcohol intake, energy-adjusted intakes of vitamin C and E, and use of antioxidative vitamin supplements. When beta-carotene intakes from supplements were considered, the inverse relation with risk of MI was slightly more pronounced. Stratification by smoking status indicated that the association was most evident in current and former smokers. No association with risk of MI was observed for dietary vitamin C and vitamin E.. The results of this observational study in the elderly population of the Rotterdam Study support the hypothesis that high dietary beta-carotene intakes may protect against cardiovascular disease. We did not observe an association between vitamin C or vitamin E and MI.

Topics: Aged; Aged, 80 and over; Antioxidants; Ascorbic Acid; beta Carotene; Diet; Female; Humans; Male; Middle Aged; Myocardial Infarction; Prospective Studies; Regression Analysis; Risk Factors; Smoking; Surveys and Questionnaires; Vitamin E

Topics: Animals; Antioxidants; beta Carotene; Dose-Response Relationship, Drug; Lipid Peroxidation; Liver; Male; Myocardial Infarction; Myocardium; Oxidants; Rats; Rats, Wistar

Topics: Antioxidants; beta Carotene; Coronary Artery Disease; Humans; Lipid Peroxidation; Myocardial Infarction; Myocardial Ischemia; Smoking; Vitamin E

Topics: Antioxidants; beta Carotene; Coronary Disease; Evidence-Based Medicine; Humans; Lipoproteins, LDL; Myocardial Infarction; Vitamin E

Topics: beta Carotene; Coronary Disease; Drug Interactions; Ethanol; Finland; Humans; Lung Neoplasms; Myocardial Infarction; Smoking

There are indications that beta-carotene, but not pre-formed vitamin A, is protective on the risk of acute myocardial infarction (AMI). The relationship between nonfatal AMI and the intake of beta-carotene and retinol was investigated in a case-control study conducted between 1983 and 1992 in northern Italy on 433 women with nonfatal AMI and 869 controls in hospital for acute, non-cardiovascular, non-neoplastic, non-digestive, non-hormone related conditions. Odds ratios (OR), with their 95% confidence intervals (CI), were computed by unconditional multiple logistic regression analysis, including terms for age, education, body mass index, smoking, alcohol and coffee drinking, menopausal status, hormone replacement therapy and history of diabetes, hypertension and hyperlipidemia. The risk of AMI was inversely related to beta-carotene intake, with an OR of 0.5 (95% CI: 0.3 to 0.8) for the highest quintile of intake compared to the lowest (chi2 trend = 10.53, p < 0.01). Retinol intake was not associated with AMI, with an OR of 0.9 (95% CI: 0.6 to 1.3) for the highest quintile of intake compared to the lowest. Analysis in separate strata of covariates indicated that the inverse association of beta-carotene intake with risk of AMI was appreciably stronger in younger, lean women with no history of diabetes or hypertension, and in current smokers. The results of this study indicate that the risk of nonfatal AMI in women is inversely related to intake of beta-carotene containing foods, but not foods containing retinol.

Topics: Adolescent; Adult; Aged; Antioxidants; beta Carotene; Case-Control Studies; Chi-Square Distribution; Female; Humans; Italy; Logistic Models; Middle Aged; Myocardial Infarction; Risk Factors; Smoking; Vitamin A

A multicenter case-control study was conducted to evaluate the relations between antioxidant status assessed by biomarkers and acute myocardial infarction. Incidence cases and frequency matched controls were recruited from 10 European countries to maximize the variance in exposure within the study. Adipose tissue needle aspiration biopsies were taken shortly after the infarction and analyzed for levels of carotenoids and tocopherols. An examination of colinearity including all covariates and the three carotenoids, alpha-carotene, beta-carotene, and lycopene, showed that the variables were sufficiently independent to model simultaneously. When examined singularly, each of the carotenoids appeared to be protective. Upon simultaneous analyses of the carotenoids, however, using conditional logistic regression models that controlled for age, body mass index, socioeconomic status, smoking, hypertension, and maternal and paternal history of disease, lycopene remained independently protective, with an odds ratio of 0.52 for the contrast of the 10th and 90th percentiles (95% confidence interval 0.33-0.82, p = 0.005). The associations for alpha- and beta-carotene were largely eliminated. We conclude that lycopene, or some substance highly correlated which is in a common food source, may contribute to the protective effect of vegetable consumption on myocardial infarction risk.

Topics: Adipose Tissue; beta Carotene; Biomarkers; Carotenoids; Case-Control Studies; Europe; Humans; Hypertension; Israel; Logistic Models; Lycopene; Male; Middle Aged; Myocardial Infarction; Obesity; Odds Ratio; Prevalence; Risk Factors; Smoking

Topics: Aged; beta Carotene; Female; Humans; Lung Neoplasms; Male; Middle Aged; Myocardial Infarction; Vitamin A

Because antioxidants may play a role in the prevention of coronary heart disease by inhibiting the peroxidation of polyunsaturated fatty acids (PUFAs), the combined association of diet-derived antioxidants and PUFAs with acute myocardial infarction (MI) was investigated. This multicenter case-control study included 674 patients and 725 control subjects in eight European countries and Israel. Fatty acid composition and alpha-tocopherol and beta-carotene levels were determined in adipose tissue; selenium level was determined in toenails. For alpha-tocopherol no association with MI was observed at any PUFA level. The overall multivariate odds ratio (OR) for low (10th percentile) versus high (90th percentile) beta-carotene was 1.98 (95% confidence interval [CI], 1.39 to 2.82). The strength of this inverse association with MI was dependent on PUFA levels (in tertiles): for low PUFA, the OR for low versus high beta-carotene was 1.79 (95% CI, 0.98 to 3.25), for medium PUFA the OR was 1.76 (95% CI, 1.00 to 3.11), and for high PUFA 3.47 (95% CI, 1.93 to 6.24). For selenium increased risk was observed only at the lowest PUFA tertile (OR, 2.49; 95% CI, 1.22 to 5.09). This interaction between selenium and PUFAs was not significant and may at least partly be explained by a higher proportion of smokers at the low PUFA level. These findings support the hypothesis that beta-carotene plays a role in the protection of PUFAs against oxidation and subsequently in the protection against MI. No evidence was found that alpha-tocopherol or selenium may protect against MI at any level of PUFA intake.

Topics: Adipose Tissue; Antioxidants; beta Carotene; Carotenoids; Case-Control Studies; Coronary Disease; Fatty Acids, Unsaturated; Humans; Male; Middle Aged; Multivariate Analysis; Myocardial Infarction; Nails; Risk Factors; Selenium; Smoking; Toes

Recent evidence suggests that oxidative damage may be involved in atherogenesis, and thus dietary antioxidants, such as beta-carotene, may reduce the risks of cardiovascular disease (CVD). We examined the association between consumption of carotene-containing fruits and vegetables and CVD mortality among 1299 elderly Massachusetts residents who provided dietary information as a part of the Massachusetts Health Care Panel Study. During a mean follow-up of 4.75 years, there were 161 deaths attributable to CVD, 48 of which were due to myocardial infarction. For total CVD death and fatal myocardial infarction, risks were lower among those residents in the highest quartile for consumption of carotene-containing fruits and vegetables as compared with those in the lowest. For death due to CVD, the relative risk (RR) was 0.54 (95% confidence interval (CI), 0.34 to 0.86; P for trend across quartiles, 0.004). For myocardial infarction the RR was 0.25 (95% CI, 0.09 to 0.67; P for trend, 0.002). These observational data are compatible with the hypothesis that increased dietary intake of carotenoids decreases the risks of CVD mortality; however, confounding cannot be ruled out. This hypothesis requires rigorous evaluation in randomized trials of sufficient size to detect reliably whether carotenoids confer small-to-moderate but clinically important protection against CVD.

Topics: Aged; Aged, 80 and over; Antioxidants; beta Carotene; Cardiovascular Diseases; Carotenoids; Cohort Studies; Diet; Eating; Female; Follow-Up Studies; Fruit; Humans; Male; Massachusetts; Multivariate Analysis; Myocardial Infarction; Prospective Studies; Risk Factors; Vegetables

Numerous experimental and clinical studies have reported a role of radical forms of oxygen in the etiology of the manifestations of reperfusion of the ischemic myocardium. However, clinical results remain controversial. The aim of this study was to ascertain the existence of reperfusion-related radical stress after thrombolysis with a marker that is easy to use and reliable. Thirty patients hospitalized for acute myocardial infarction were involved in the study. Of these, 18 had been subjected to intravenous thrombolysis (Group I) and 12 had not (Group II). They were compared to two control groups who had no history of myocardial infarction. Of these, 16 were patients with coronary heart disease hospitalized for stable angina (Group III) and 17 were patients free of any known cardiovascular disease (Group IV). Radical activity was assessed in plasma samples taken from a peripheral vein over a 10-day period of hospitalization by measuring (1) malondialdehydes (MDA) concentrations using fluorometry techniques or HPLC, (2) the antioxidant activity of glutathione peroxidase (GPx) and (3) the concentration of various antiradical compounds (beta-carotene, vitamins A and E, uric acid). All patients in Group I had a patent artery on coronary angiography and showed a significant increase in plasma MDA when compared to those who had not been subjected to thrombolysis (3.15 +/- 0.62 and 2.70 +/- 0.40 mole/l of plasma, respectively). Furthermore, GPx plasma activity was also significantly increased following thrombolysis. By contrast, there was no significant alteration in the antiradical compounds measured. These data suggest that MDA measurements (an early measurement 1-2 days and a late measurement 5-7 days after reperfusion) by fluorometry is a good marker of radical stress during reperfusion in man. The assessment of this marker in patients might represent a simple and reliable test of reperfusion efficacy following thrombolysis, and it might enable one to test the effect of various antioxidant therapies associated with thrombolytic treatment.

Topics: Aged; beta Carotene; Carotenoids; Chromatography, High Pressure Liquid; Female; Fibrinolysis; Free Radicals; Glutathione Peroxidase; Humans; Kinetics; Male; Malondialdehyde; Middle Aged; Myocardial Infarction; Myosins; Thiobarbituric Acid Reactive Substances; Thrombolytic Therapy; Uric Acid; Vitamin E

Of 138 patients with suspected acute myocardial infarction (AMI), 29 were excluded. Remaining 109 patients and 182 healthy controls of similar age and sex and same population were studied in detail for demographic variables, clinical and biochemical data for comparison. Mean age, sex, body weight, body mass index and blood pressures were comparable in the two groups whereas blood lipids, blood glucose and cardiac enzymes were raised in AMI patients compared to controls. Mean levels of vitamin C, E, A and beta-carotene were significantly less in AMI patients than controls whereas the lipid peroxides were significantly higher in AMI patients. The reduction in vitamin C and beta-carotene was more marked than decrease in other vitamins. With in AMI patients, those 28 patients who had cardiac arrhythmias showed greater decrease in vitamins compared to rest of the patients. Within both groups, smokers and diabetes patients had greater reduction in vitamin C and beta-carotene than other patients and subjects without confounding factors. Smokers also had higher lipid peroxides level than non-smokers. The inverse relation between AMI and low plasma vitamin levels remained significant after exclusion of patients with smoking and diabetes. These findings suggest that vitamin deficiency may be a risk factor of AMI and these patients may benefit by administration of these antioxidant vitamins for primary and secondary prevention of coronary artery disease.

Topics: Antioxidants; Arrhythmias, Cardiac; Ascorbic Acid; beta Carotene; Carotenoids; Case-Control Studies; Female; Humans; Lipid Peroxides; Male; Middle Aged; Myocardial Infarction; Oxidative Stress; Prospective Studies; Vitamin A; Vitamin E; Vitamins

Serum beta-carotene levels in patients with cardiovascular disease and control subjects were measured. The mean values for beta-carotene were found to be 82.2 +/- 3.5 micrograms/dl for the cases as a single group, 74.83 +/- 5.6 micrograms/dl in acute myocardial infarction (AMI) cases, 88.19 +/- 6.1 micrograms/dl in atherosclerotic cases, 85.11 +/- 6.1 micrograms/dl in others and 118.2 +/- 4.3 micrograms/dl in controls. beta-carotene levels in the cases were significantly lower than in the controls (P < 0.05). Serum beta-carotene levels in cases and controls were also compared to take account of age, sex and smoking status. Our data indicate that there are apparent associations between serum beta-carotene levels, sex and smoking status.

Topics: Adult; Age Factors; Aged; Arteriosclerosis; beta Carotene; Cardiovascular Diseases; Carotenoids; Female; Humans; Male; Middle Aged; Myocardial Infarction; Sex Characteristics; Smoking

Laboratory and epidemiological studies suggest that the antioxidants, vitamin E and beta-carotene, protect against coronary heart disease. In a European multicentre case-control study alpha-tocopherol and beta-carotene concentrations were measured in adipose-tissue samples collected in 1991-92 from 683 people with acute myocardial infarction and 727 controls. Mean adipose-tissue beta-carotene concentration was 0.35 microgram/g in cases and 0.42 in controls, with age-adjusted and centre-adjusted mean difference 0.07 microgram/g (95% confidence interval [CI] 0.04-0.10). Mean alpha-tocopherol concentrations were 193 micrograms/g and 192 micrograms/g for cases and controls, respectively. The age-adjusted and centre-adjusted odds ratio for risk of myocardial infarction in the lowest quintile of beta-carotene as compared with the highest was 2.62 (95% CI 1.79-3.83). Additional control for body-mass index and smoking reduced the odds ratio to 1.78 (95% CI 1.17-2.71); other established risk factors did not substantially alter this ratio. The increased risk was mainly confined to current smokers: the multivariate odds ratio in the lowest beta-carotene quintile in smokers was 2.39 (95% CI 1.35-4.25), whereas it was 1.07 for people who had never smoked. A low alpha-tocopherol concentration was not associated with risk of myocardial infarction. Our results support the hypothesis that high beta-carotene concentrations within the normal range reduce the risk of a first myocardial infarction. The findings for alpha-tocopherol are compatible with previous observations of reduced risk among vitamin E supplement users only. The consumption of beta-carotene-rich foods such as carrots and green-leaf vegetables may reduce the risk of myocardial infarction.

Topics: Adipose Tissue; Adult; Aged; Antioxidants; beta Carotene; Carotenoids; Case-Control Studies; Humans; Male; Middle Aged; Myocardial Infarction; Odds Ratio; Risk Factors; Vitamin E

Topics: Adipose Tissue; Adult; Aged; beta Carotene; Body Weight; Carotenoids; Chromatography, High Pressure Liquid; Humans; Lipid Peroxidation; Lipoproteins, LDL; Male; Middle Aged; Myocardial Infarction; Risk Factors; Smoking; Vitamin E

The synthetic liposoluble antioxidant BAT. 120 mg/kg, was found to produce markedly protective effects in a rat model of coronary occlusive myocardial infarction, whereas the water soluble BAT analogue, 4-Oxy-3,5-ditretbutylphenyl phosphonic acid sodiate (SFN-6), 100 mg/kg, displayed no protective effects. The natural antioxidant beta-carotene capable of displaying antioxidative activity at low partial O2 pressures was shown to reduce the size of postinfarct scar by 34% when given in a dose of 20 mg/kg. The synthetic antioxidants, BAT and SFN-6 given in doses of 100 to 120 mg/kg each decreased antioxidant enzyme activities in the intact or infarct-related myocardium. beta-carotene was found to lack inhibitory effects on the myocardial antioxidant enzymes, thus enhancing its cardioprotective properties.

Topics: Animals; Antioxidants; beta Carotene; Carotenoids; Male; Myocardial Infarction; Myocardium; Necrosis; Rats; Rats, Inbred Strains

To establish whether plasma vitamin measurements made after acute myocardial infarction (AMI) can be used in case-control studies of coronary artery disease, the short-term effect of AMI on plasma concentrations of 25-hydroxyvitamin D3, beta-carotene, vitamin E and retinol was investigated. Sequential measures of these vitamins were made during the first 48 hours after AMI in 13 patients admitted to the hospital within 4 hours after the onset of symptoms. Plasma levels of 25-hydroxyvitamin D did not change significantly during the first 12 hours after onset of symptoms. Beta-carotene levels increased significantly (p less than 0.05) during the first 12 hours and then decreased, whereas levels of vitamin E and retinol progressively decreased during the first 48 hours by 26 and 25%, respectively. These results suggest that, of these vitamins, only plasma measurements of 25-hydroxyvitamin D3 collected within 12 hours of onset of symptoms may provide reliable information for case-control studies of AMI.

Topics: Aged; beta Carotene; Calcifediol; Carotenoids; Case-Control Studies; Female; Humans; Male; Middle Aged; Myocardial Infarction; Time Factors; Vitamin A; Vitamin E; Vitamins