Relationship between the extent of coronary artery disease and indicators of free radical activity

The Role of Oxidative Stress and Antioxidants in Cardiovascular Comorbidities in COPD

Oxidative stress driven by several environmental and local airway factors associated with chronic obstructive bronchiolitis, a hallmark feature of COPD, plays a crucial role in disease pathomechanisms. Unbalance between oxidants and antioxidant defense mechanisms amplifies the local inflammatory processes, worsens cardiovascular health, and contributes to COPD-related cardiovascular dysfunctions and mortality. The current review summarizes recent developments in our understanding of different mechanisms contributing to oxidative stress and its countermeasures, with special attention to those that link local and systemic processes. Major regulatory mechanisms orchestrating these pathways are also introduced, with some suggestions for further research in the field.

Association between Oxidative Burden and Restenosis: A Case-Control Study

Background

In-stent restenosis (ISR) is an important clinical complication that occurs following stent implantation. The application of drug-eluting stents (DES) and even consumption of drugs such as antiplatelet agents and statins are not completely effective in reducing ISR risk. Since the number of these patients continues to rise, it is pivotal to detect patients who are at a higher risk of ISR. In addition, identification of biochemical markers of ISR could give the right perspective on choosing the proper strategy to treat these patients. Several pathophysiological pathways including oxidative stress (OS) are implicated in the progression of ISR. Hence, this study aimed to evaluate the association between oxidative/anti-oxidative markers and ISR.

Methods

This was a case-control study which comprised 21 ISR, 26 NISR (non-ISR), and 20 healthy subjects. The serum levels of OS markers including malondialdehyde (MDA), thiol groups (GSH), total antioxidant capacity (TAC), and the activity of serum antioxidant enzymes such as glutathione peroxidase (GPx) and superoxide dismutase (SOD) were assessed by colorimetric methods. The overall oxidative burden was assessed using a pro-oxidant-antioxidant balance (PAB) assay.

Results

MDA levels were considerably higher in the ISR group when compared to healthy subjects (P = 0.004). PAB also indicated significantly higher values in both ISR (P < 0.001) and NISR (P < 0.001) groups related to healthy subjects. No significant differences were observed between the studied groups regarding thiol levels, antioxidant enzyme activities, and TAC. Multinomial logistic regression analysis showed that elevated serum levels of MDA (OR: 1.028, 95% CI: 1.008-1.048; P = 0.006) and PAB (OR: 1.076, 95% CI: 1.017-1.139; P = 0.011) were significantly associated with higher ISR risk; however, increased values of TAC (OR: 0.990, 95% CI: 0.982-0.999; P = 0.030) were significantly associated with decreased ISR risk, while after adjustment for confounders, only SOD activity (OR: 0.0, 95% CI: 0.0-0.0; P < 0.001) and PAB value (OR: 1.866, 95% CI: 1.856-1.900; P < 0.001) showed association with ISR risk.

Conclusion

According to the present findings, some oxidative and antioxidative markers like PAB and SOD activity showed the potential in the prediction of ISR risk.

Effect of Moderate Wine Consumption on Oxidative Stress Markers in Coronary Heart Disease Patients

Evidence from research studies reports that wine consumption is associated with lower cardiovascular disease risk, partly through the amelioration of oxidative stress. The aim of the present study was to examine the effect of regular light to moderate wine consumption from coronary heart disease (CHD) patients compared to the effect induced by alcohol intake without the presence of wine microconstituents, on oxidation-induced macromolecular damage as well as on endogenous antioxidant enzyme activity. A randomized, single-blind, controlled, three-arm parallel intervention was carried out, in which 64 CHD patients were allocated to three intervention groups. Group A consumed no alcohol, and Group B (wine) and Group C (ethanol) consumed 27 g of alcohol/day for 8 weeks. Blood and urine samples were collected at baseline and at 4 and 8 weeks. Urine oxidized guanine species levels, protein carbonyls, thiobarbituric acid substances (TBARS) levels, as well as superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities, were measured. Oxidized guanine species and protein carbonyl levels were significantly increased in the ethanol group during the intervention and were significantly decreased in the wine group. These results support the idea that wine’s bioactive compounds may exert antioxidant actions that counteract the macromolecular oxidative damage induced by alcohol in CHD patients.

The protective effects of Salvia officinalis essential oil compared to simvastatin against hyperlipidemia, liver, and kidney injuries in mice submitted to a high-fat diet

The present study was undertaken to evaluate the effects of Salvia officinalis essential oil (SEO) and simvastatin in hyperlipidemic mice. Animals were randomly divided into four groups. The control group received a standard diet. The high-fat diet (HFD) group received HFD. The third and fourth groups received HFD associated either with simvastatin (2.5 mg/kg bw) or with SEO (4 mg/kg bw). All animals were sacrificed after 8 weeks of treatment. SEO and simvastatin reduced in HFD mice body weight gain, hyperlipidemia, disruption of liver and renal functions and reactive oxygen species production. In fact, total cholesterol, triglycerides, total lipids, and low-density lipoprotein cholesterol levels, as well as aspartate transaminase, alanine transaminase, gamma-glutamyltranspeptidase and lactate dehydrogenase activities were reduced, while fecal lipids increased compared to those of HFD mice. The lipid-lowering effect of SEO was more effective than that of simvastatin. PRACTICAL APPLICATIONS: High-fat diet provokes hyperlipidemia, atherosclerosis, and abnormal lipid metabolism leading to the development of hepatic and renal dysfunctions as well as perturbations of the antioxidant status in liver and kidney. The results of this research highlight the beneficial effects of SEO in the management of these disorders without inducing side effects; in fact, the plant essential oil decreased lipids and improved the antioxidant status more than did a synthetic drug.

Atherothrombosis and Oxidative Stress: Mechanisms and Management in Elderly

SIGNIFICANCE

The incidence of cardiovascular events (CVEs) increases with age, representing the main cause of death in an elderly population. Aging is associated with overproduction of reactive oxygen species (ROS), which may affect clotting and platelet activation, and impair endothelial function, thus predisposing elderly patients to thrombotic complications. Recent Advances: There is increasing evidence to suggest that aging is associated with an imbalance between oxidative stress and antioxidant status. Thus, upregulation of ROS-producing enzymes such as nicotinamide adenine dinucleotide phosphate (NADPH) oxidase and myeloperoxidase, along with downregulation of antioxidant enzymes, such as superoxide dismutase and glutathione peroxidase, occurs during aging. This imbalance may predispose to thrombosis by enhancing platelet and clotting activation and eliciting endothelial dysfunction. Recently, gut-derived products, such as trimethylamine N-oxide (TMAO) and lipopolysaccharide, are emerging as novel atherosclerotic risk factors, and gut microbiota composition has been shown to change by aging, and may concur with the increased cardiovascular risk in the elderly.

CRITICAL ISSUES

Antioxidant treatment is ineffective in patients at risk or with cardiovascular disease. Further, anti-thrombotic treatment seems to work less in the elderly population.

FUTURE DIRECTIONS

Interventional trials with antioxidants targeting enzymes implicated in aging-related atherothrombosis are warranted to explore whether modulation of redox status is effective in lowering CVEs in the elderly. Antioxid. Redox Signal. 27, 1083-1124.

Plasma glutathione reductase activity and prognosis of septic shock

BACKGROUND

Our aim was to investigate whether plasma glutathione reductase (GR) activity is well correlated with the erythrocyte-reduced glutathione (GSH)/glutathione disulfide (GSSG) ratio and is associated with the mortality of septic shock.

MATERIALS AND METHODS

This study was conducted on male Sprague-Dawley rats and patients admitted to the intensive care unit with septic shock. To induce endotoxemia in rats, vehicle or lipopolysaccharide (LPS) at dosages of 5 or 10 mg/kg were injected into a tail vein. Animals were then euthanized 6 h post-LPS. Based on the 28-d mortality, the enrolled patients were divided into the survivors and nonsurvivors. We obtained blood samples from patients at admission (0 h) and 24 h after admission to the intensive care unit.

RESULTS

In endotoxemic rats, the erythrocyte GSH/GSSG ratio, erythrocyte GR activity, and plasma GR activity in the 10 mg/kg of LPS group were lower than those in the sham and 5 mg/kg of LPS groups. In patients with septic shock, decrease in plasma GR activity at 24 h was independently associated with an increase in 28-d mortality (odds ratio, 0.828; 95% confidence interval, 0.690-0.992, P = 0.041). Plasma GR activity was correlated with erythrocyte GR activity (Spearman ρ = 0.549, P < 0.001) and the erythrocyte GSH/GSSG ratio (rho = 0.367, P = 0.009) at 24 h.

CONCLUSIONS

Plasma GR activity was well correlated with erythrocyte GR activity and the erythrocyte GSH/GSSG ratio, and a decrease in plasma GR activity was associated with an increase in the mortality of septic shock patients.

A multimarker approach for the prediction of coronary artery disease: cost-effectiveness analysis

OBJECTIVES

Coronary artery disease (CAD), as the leading cause of death, poses a huge economic burden on health-care systems. We used a multi-marker approach to explore discriminative abilities of several lipid, inflammatory, and oxidative stress/antioxidative defense markers as CAD predictors. We assessed their cost-effectiveness compared with the Framingham risk score (FRS).

METHODS

Using a decision model, we evaluated the costs, accuracy, and cost-effectiveness of each model. The FRS was used as the baseline model. Other models were formed with the consecutive addition of selected markers: apolipoprotein A-I (apoA-I), apolipoprotein B (apoB), apolipoprotein (a) [apo(a)] isoform, lipoprotein (a), high-sensitivity C-reactive protein, malondialdehyde, superoxide dismutase (SOD), sulfhydryl, and superoxide anion (O(2) (-) ). A best-case model was formed from a combination of diagnostic markers to yield the best patient stratification algorithm. All models were assessed by their predictive probabilities using receiver operating characteristic curves. To accomplish our goals, we recruited 188 CAD patients (verified by coronary angiography) and 197 asymptomatic CAD-free subjects for comparison. The analysis was performed from a third-party payer perspective.

RESULTS

Only two strategies had outstanding discriminative abilities: the best-case model (FRS, SOD, and O(2) (-) ) and FRS plus SOD with area under the curve (AUC) values of 0.924 and 0.906, respectively. The cost-effectiveness ratio varied between €593 per AUC for the baseline model to €2425 per AUC for FRS plus apo(a) isoform. Strategies involving oxidative stress/antioxidative defense markers were more cost-effective than strategies involving lipid or inflammatory markers. All results were robust.

CONCLUSION

Our results support the feasibility of a multimarker approach for CAD screening. The introduction of oxidative stress/antioxidative defense markers in the clinical laboratory would be convenient and cost-effective.

Atherogenic dyslipidemia and oxidative stress: a new look

Although results from in vitro studies and clinical trials demonstrate strong associations between oxidative stress and cardiovascular risk, to date still no convincing data are available to suggest that treatment with antioxidants might reduce vascular events. Oxidative modifications of low-density lipoproteins (LDL) represent an early stage of atherosclerosis, and small, dense LDL are more susceptible to oxidation than larger, more buoyant particles. Oxidized LDL are independent predictors of subclinical and clinical atherosclerosis. Recent studies suggested that novel therapeutic strategies may take into account the removal of such particles from circulation. Future research is required to explore the potential synergistic impact of markers of oxidative stress and atherogenic dyslipidemia, particularly small dense LDL, on cardiovascular risk.

Determination of Prooxidant—Antioxidant Balance After Acute Coronary Syndrome Using a Rapid Assay: A Pilot Study

The purpose of the current study was to investigate a novel measure of oxidative stress in patients with acute coronary syndrome (ACS) using a pro-oxidant—antioxidant balance (PAB) assay, which is simple and rapid. Blood samples were taken from 94 patients admitted with ACS. Pro-oxidant—antioxidant balance values were determined in the first and second 12 hours after the onset of symptoms and compared with values for 81 age- and sex-matched controls. The mean PAB values in the first and second 12-hour samples of patients were both significantly higher than that of controls (P < .001). Among patients, PAB values were also significantly higher in the second samples compared with the first samples (P < .001). These findings indicate a heightened state of oxidative stress following ACS and suggest that the PAB value may be considered as a cardiovascular risk predictor to estimate the extent of oxidative stress.

Glutathione, vitamin E and oxidative stress in coronary artery disease: relevance of age and gender

BACKGROUND

Observational studies suggest that low levels of antioxidants are associated with high risk for coronary artery disease (CAD). We investigated whether the biomarkers of oxidative balance undergo the same modifications in all CAD patient groups, regardless of gender and age.

MATERIALS AND METHODS

One hundred sixty-eight CAD patients and 107 healthy controls were assayed for plasma levels of reduced glutathione (GSH), alpha- and gamma-tocopherol (alpha- and gamma-T) as endogenous antioxidants. A damage score (DS), representative of oxidative stress status, was calculated. ANCOVA models were used to test the association between antioxidants, DS and CAD and its modulation by age and gender.

RESULTS

The DS was higher in CAD than in controls. GSH levels, were lower in CAD patients (mean +/- SEM: 57.61 +/- 1.87 micromol 10 g(-1) haemoglobin vs. 68.55 +/- 2.23 in controls, P < 0.0006) in males and in older subjects. Levels of other antioxidants exhibited a complex pattern. Overall, no difference was found in alpha- and gamma-T contents between CAD and controls, but lower alpha-T values were observed in CAD females. A significant interaction between CAD status and gender was observed (P = 0.003).

CONCLUSIONS

Our study shows that the involvement of antioxidants in CAD is related to patients' characteristics. These findings may be relevant in planning antioxidant therapies.

Sialic acid and oxidizability of lipid and proteins and antioxidant status in patients with coronary artery disease

The aim of this study was to investigate the possible relationship between serum total sialic acid (TSA) concentration, recently shown to be a cardiovascular risk factor, and lipid and protein oxidation and antioxidant status and the severity of coronary artery disease (CAD) according to the obstructive vessel number in patients. The study was carried out on a total of 200 patients (142 men and 58 women) who were hospitalized for elective coronary angiographic evaluation with complaint of typical angina pectoris. According to the results of angiography, 150 patients had angiographically proven CAD (CAD group) and 50 patients had a history suggestive of angina pectoris but normal coronary angiograms (control group). The CAD group was further divided into single-, double- and triple-vessel disease groups according to the number of vessels involved. Lipid parameters were determined by routine laboratory methods. Plasma malondialdehyde (MDA) and vitamin E concentrations were determined by high-performance liquid chromatography. TSA and other oxidant and antioxidant parameters were studied spectrophotometrically. Our results demonstrated significant increases both in TSA levels and in indicators of oxidative stress in the patients with CAD compared with the controls. However, antioxidant parameters were decreased in the patients with CAD. We found strong positive correlations between TSA and plasma MDA, Delta-MDA which represents the degree of oxidative modification of apolipoprotein B-containing lipoproteins, serum protein carbonyls and apolipoprotein B and weak correlations between TSA and low density lipoprotein cholesterol, triacylglycerol, paraoxonase, glutathione peroxidase (GPx), vitamin C and vitamin E. In conclusion, TSA is related to markers of lipid and protein oxidation, paraoxonase and GPx activities, vitamin C and E levels and the severity of CAD.

Correlation of oxidative stress parameters and inflammatory markers in coronary artery disease patients

OBJECTIVES

In addition to many traditional risk factors for coronary artery disease (CAD) development, enhanced oxidative stress and inflammation are serious conditions that may also be classified as novel risk factors. In the present study, we assessed the relationship between several parameters of oxidative stress status [malonaldehyde (MDA), superoxide anion (O(2)(-)) and plasma and erythrocyte superoxide dismutase (SOD) activities] with high sensitivity C-reactive protein (hsCRP) and fibrinogen as inflammation markers.

DESIGN AND METHODS

Oxidative stress status parameters, inflammation markers and lipid status parameters were measured in 385 subjects [188 coronary heart disease (CHD) patients with angiographically diagnosed coronary artery disease (CAD), 141 patients with occlusion >50% in at least one major coronary artery (CAD+) and 47 patients with occlusion less than 50% (CAD-), and 197 CHD-free middle-aged subjects (the control group)].

RESULTS

The plasma MDA concentration and the level of O(2)(-) in plasma were significantly higher in combination with significantly lower SOD activity in the CAD+ group vs. the control group. By using multiple stepwise regression analysis, fibrinogen and hsCRP showed independent correlation with MDA. Binary logistic regression analysis indicated that both MDA and O(2)(-) were significantly associated with CAD development and adjustment for inflammatory markers weakened this association in the case of MDA.

CONCLUSIONS

The relationship between oxidative stress parameters and inflammatory species suggest their strong mutual involvement in atherosclerosis development that leads to CAD progression.

Lipid and protein oxidation and antioxidant status in patients with angiographically proven coronary artery disease

OBJECTIVES

We aimed to evaluate the association of lipid peroxidation, protein oxidation and antioxidant system, and to assess an association with the severity of the disease, in patients with and without coronary artery disease (CAD) documented by coronary angiography.

DESIGN AND METHODS

The population included 208 patients, undergoing clinically indicated coronary angiography. While the subjects with normal coronary angiograms (n=54) were evaluated as controls, the patients with CAD (n=154) were divided into three categories according to the number of diseased coronaries; one-vessel (n=50), two-vessels (n=51) and three-vessels (n=53). Lipid parameters were determined by routine laboratory methods. Plasma malondialdehyde and vitamin E concentrations were determined with the high-performance liquid chromatography. Other oxidant and antioxidant parameters were studied spectrophotometrically.

RESULTS

While plasma malondialdehyde levels, the susceptibilities of erythrocyte and apolipoprotein B containing lipoproteins to in vitro induced oxidative stress, serum protein carbonyls, low density lipoprotein-cholesterol, triglyceride, apolipoprotein B and lipoprotein (a) levels had significantly increased, high-density lipoprotein-cholesterol and apolipoprotein AI levels, erythrocyte glutathione peroxidase, glutathione reductase, glucose 6 phosphate dehydrogenase, serum catalase, paraoxonase and arylesterase activities, plasma vitamin E and C and carotenoid levels had significantly decreased. The odds ratios for one-, two-, and three-vessel disease increased across especially higher tertiles of concentrations for oxidation parameters and lower tertiles of concentrations for antioxidant parameters.

CONCLUSIONS

According to the results, we suggest that increased lipid and protein oxidation products and decreased antioxidant enzymes and vitamins contribute to increased oxidative stress which in turn is related to the severity of the disease.

Relationship between plasma glutathione levels and cardiovascular disease in a defined population: the Hisayama study

BACKGROUND AND PURPOSE

Glutathione (GSH) appears to have marked antioxidant activities and therefore may prevent cardiovascular disease (CVD). However, there are very few reports on this subject. In a community-based case-control study, we tested the hypothesis that low levels of plasma GSH are closely associated with CVD and its clinical types.

METHODS

The association between fasting plasma total GSH (tGSH) levels and CVD were assessed using conditional logistic regression analysis among 134 CVD cases and 435 age- and sex-matched healthy control subjects.

RESULTS

Mean tGSH concentrations were lower in all CVD cases than in the control subjects (3.06 versus 3.71 micromol/L; P=0.0001). Among the CVD types, both the cerebral infarction cases (2.98 versus 3.59 micromol/L; P=0.001) and cerebral hemorrhage cases (2.51 versus 3.43 micromol/L; P=0.0027) had significantly lower tGSH levels than the corresponding control groups had. The same tendency was observed for cases of subarachnoid hemorrhage (3.45 versus 3.83 micromol/L; P=0.36) and myocardial infarction (3.65 versus 3.77 micromol/L; P=0.69), but these differences were not statistically significant. After adjustment for other confounding factors, the risk of CVD was significantly lower in the third (adjusted odds ratio, 041; 95% CI, 0.21 to 0.77) and the fourth quartiles (adjusted odds ratio, 0.25; 95% CI, 0.12 to 0.51) than in the first. This association was most prominent in patients with lacunar infarction or cerebral hemorrhage.

CONCLUSIONS

These findings suggest that reduced plasma tGSH levels are a risk factor for CVD, especially for cerebral small vessel disease.

Genomic association/linkage of sodium lithium countertransport in CEPH pedigrees

Little is known about genetic determinants explaining variation in the erythrocyte sodium-lithium countertransport (SLC), an intermediate phenotype of essential hypertension. We characterized the SLC in immortalized lymphoblasts and showed that its behavior is similar to that of erythrocyte SLC. We then performed association and linkage analyses of the SLC in immortalized lymphoblasts from 5 large pedigrees from the Center d'Etude du Polymorphisme Humain (CEPH) genomics repository. The results of these analyses showed that a number of genomic regions harboring genes involved in glutathione metabolism might explain variations in SLC activity. These findings support evidence that thiol groups play a central role in SLC activity.

NADH/NADPH oxidase p22 phox C242T polymorphism and lipid peroxidation in coronary artery disease

The nicotinamide adenine dinucleotide (NADH)/nicotinamide adenine dinucleotide phosphate (NADPH) oxidase system is a major source of superoxide anion (.O2-) production in the human vasculature and may therefore influence lipid peroxidation and severity of atherosclerosis. This study aimed to investigate a hypothetical influence of the p22 phox C242T polymorphism on the generation of malondialdehyde (MDA), extent and clinical onset of coronary artery disease (CAD) in patients. We studied 108 male Caucasians with angiographically documented CAD and 45 controls free of vascular disease under 60 years of age. p22 phox C242T genotypes and MDA levels were determined. Additional information was obtained from each subject on classic risk factors and clinical events of CAD. Genotype distribution in CAD-patients and controls was thymine-thymine (TT): 13.8% (13.3%), cytosine-thymine (CT): 46.3% (53.3%) and cytosine-cytosine (CC): 39.8% (33.3%), respectively. No significant influence was seen of the p22 phox C242T polymorphism on corresponding mean MDA levels in both groups. Furthermore, age at onset of first time angina pectoris (AP) and myocardial infarction (MCI) was not significantly different between genotype groups. It is concluded that the C242T polymorphism of the p22 phox gene is not associated with lipid peroxidation as measured by MDA, and is not a genetic risk marker for CAD Caucasians.

Serum glutathione in adolescent males predicts parental coronary heart disease

BACKGROUND

Traditional risk factors account for only half of the morbidity and mortality from coronary heart disease (CHD). There is substantial evidence that oxidative injury plays a major role in the atherosclerotic process. Thus, antioxidants may protect against development of atherosclerosis. Glutathione, an intracellular tripeptide with antioxidant properties, may be protective.

METHODS AND RESULTS

This case-control study compared total serum glutathione (tGSH) in 81 adolescent male offspring of parents with premature CHD (ie, before 56 years of age) and 78 control male offspring of parents without known or suspected CHD. Case offspring had significantly lower tGSH than control offspring. In multiple logistic regression with parental CHD status as the dependent variable, age entered as a covariate, and other CHD risk factors competing to enter the model as significant independent predictor variables, LDL cholesterol (odds ratio [OR], 2.15 [units=1.5 SD]; 95% CI, 1.21 to 3.82), tGSH (OR, 0.40; 95% CI, 0.22 to 0.71), HDL cholesterol (OR, 0.42; 95% CI, 0.22 to 0.78), and total serum homocysteine (OR, 2.6; 95% CI, 1.35 to 5.02) entered the model as significant predictors of parental CHD status.

CONCLUSIONS

Low tGSH in adolescent boys is a significant independent predictor of parental CHD, in addition to elevated LDL cholesterol, low HDL cholesterol, and elevated total serum homocysteine concentrations.

Coronary artery disease, hypertension, ApoE, and cholesterol: a link to Alzheimer's disease?

The premature presence of senile plaques (SP) in coronary artery disease (CAD), and neurofibrillary tangles (NFT) as well as SP in hypertension (HyperT), suggest a neuropathologic link between CAD, HyperT, and AD. Previous MI, CAD and HyperT often occur in and may increase the risk of AD. Expression of Apo-E4 likely increases risk of CAD by elevating blood cholesterol and the risk of AD via proposed interactions with beta-amyloid and/or free radicals (FRs). Any Apo-E4 effect is vague, but FRs probably mediate vascular damage in HyperT. Increasing FR content in the blood is related to increasing CAD severity, while the severity of elevated FR level correlates with how deep into a blood vessel there is activation of the FR scavenger enzyme, superoxide dismutase (SOD). The ApoE genotype and SP/NFT areal densities were determined in a large population of non-demented CAD, HyperT and non-heart disease (non-HD) control subjects, and compared to findings in a similar number of AD patients. ApoE immunoreactivity was determined in many individuals. Cholesterol content in cortex was determined by HPLC in a small, loosely age-matched group of Apo-E4 genotype-matched AD, CAD and non-HD subjects. SOD immunoreactivity was also assessed in a number of subjects. The Apo-E4 genotype frequency was increased in CAD, HyperT and AD compared to non-HD controls. Dose of Apo-E4 correlated with SP densities, but not NFT, and only in the non-demented groups. Essentially all SP in CAD, HyperT and non-HD subjects were ApoE-immunoreactive. Cortical cholesterol was increased in CAD and AD compared to controls. SOD immunoreactivity was similar in HyperT and AD; SP were immunodecorated in both. AD, CAD and HyperT may be linked, while CAD and HyperT subjects may die of heart disease before showing cognitive change.

Breath pentane and plasma lipid peroxides in ischemic heart disease

This study examined the relationship between breath pentane and plasma lipid peroxide levels sampled simultaneously in patients with stable angina (n = 17), unstable angina (n = 23), and controls (n = 10). Plasma lipid peroxides were measured in venous blood as the adduct formed between thiobarbituric acid and malondialdehyde (MDA) using high performance liquid chromatography. Pentane was measured in end-expiratory air using gas chromatography. MDA concentrations in stable (1.81 +/- 0.84 mumol/l) and unstable (1.5 +/- 1.23 mumol/l) angina were not different. However, both groups had significantly (p < 0.005) elevated MDA levels compared to controls (0.41 +/- 0.26 mumol/l). Breath pentane was 0.20 +/- 0.12 nmol/l in controls and not different from stable angina (0.26 +/- 0.20 nmol/l) or unstable angina (0.15 +/- 0.07 nmol/l). When the data from all three groups were combined, there was no correlation between pentane and MDA (rho = -0.09, p = 0.54). In five of the unstable angina patients treated with balloon angioplasty, MDA in pulmonary arterial blood rose by 69 +/- 15% (p < 0.01), and breath pentane rose by 73 +/- 20% (p < 0.01) immediately after balloon deflation. One minute after balloon deflation MDA and pentane had returned to preinflation levels. The results suggest that basal levels of pentane are less useful than MDA as an index of lipid peroxidation in patients with coronary artery disease. However, breath pentane appears to be a sensitive index of reperfusion-induced lipid peroxidation.

Increased incidence of neurofibrillary tangles (NFT) in non-demented individuals with hypertension

The incidence rates and numerical densities of argryophilic neurofibrillary tangles (NFT) and senile plaques (SP) were determined in non-demented individuals and subjects with Alzheimer's disease (AD). The non-AD subjects were grouped according to cardiac status; those individuals with critical coronary artery disease (cCAD), those hypertensive individuals without cCAD (HyperT), and those without heart disease (non-HD). The incidence and densities of SP and NFT were significantly greater in AD than any of the non-demented groups. The prevalence of SP was increased in both HyperT and cCAD compared to non-HD controls, while NFT occurrence was accentuated in non-demented HyperT subjects only. The densities of SP and NFT in HyperT were elevated compared to cCAD or both cCAD and non-HD controls; NFT densities were similar in cCAD and non-HD. NFT density increased with increasing age in only the non-HD and cCAD groups, suggesting a possible relationship between disease process and NFT formation in the AD and HyperT populations.

Neutrophils may contribute to the morbidity and mortality of claudicants

Peripheral arterial occlusive disease is a common cause of morbidity in middle-aged men; 5 per cent of those aged over 50 years suffer from intermittent claudication. While claudication itself is not fatal, claudicants have a mortality rate approximately three times that of non-claudicating men of the same age, mainly from cardiovascular disease. This review examines the evidence for involvement of the neutrophil in this increased mortality and describes the possible pathogenesis. It also discusses how treatment of claudication may modify neutrophil behaviour, reducing subsequent mortality and morbidity rates.