Monocyte chemoattractant protein-1 involvement in the alpha-tocopherol-induced reduction of atherosclerotic lesions in apolipoprotein E knockout mice

We studied the effects of alpha-tocopheryl acetate supplementation on the development of fatty streaks and its ability to modulate the expression of monocyte chemoattractant protein (MCP)-1 in aortic lesions of apolipoprotein E knockout mice. For this purpose, 16-week-old apolipoprotein E knockout mice received alpha-tocopherol supplementation (800 mg)/kg diet) for 6 weeks. After this time, total and lipoprotein cholesterol in the serum, hepatic tocopherol, aortic lesion area and MCP-1 (protein and mRNA) expression were analysed. Our present results showed that the dietary supplementation with alpha-tocopherol did not reduce serum cholesterol nor change lipoprotein profile, but it reduced the area of the aortic lesion by 55 %. The reduction in the lesion size was correlated with the reduced expression of MCP-1 mRNA and protein, as detected by real-time quantitative polymerase chain reaction and immunohistochemistry respectively. In conclusion, the results obtained here are relevant to the study of atherosclerosis, as they correlate the effectiveness of vitamin E supplementation in inhibiting the plaque formation with diminished expression of MCP-1 at the aortic lesion.     

Dietary soy protein isolate ameliorates atherosclerotic lesions in apolipoprotein E-deficient mice potentially by inhibiting monocyte chemoattractant protein-1 expression

Soy-based diets reportedly protect against the development of atherosclerosis; however, the underlying mechanism(s) for this protection remains unknown. In this report, the mechanism(s) contributing to the atheroprotective effects of a soy-based diet was addressed using the apolipoprotein E knockout (apoE-/-) mice fed soy protein isolate (SPI) associated with or without phytochemicals (SPI+ and SPI-, respectively) or casein (CAS). Reduced atherosclerotic lesions were observed in aortic sinus and enface analyses of the descending aorta in SPI+- or SPI(-)-fed apoE-/- mice compared with CAS-fed mice. SPI+-fed mice showed 20% fewer lesions compared with SPI(-)-fed mice. Plasma lipid profiles did not differ among the 3 groups, suggesting alternative mechanism(s) could have contributed to the atheroprotective effect of soy-based diets. Real-time quantitative PCR analyses of proximal aorta showed reduced expression of monocyte chemoattractant protein-1 (MCP-1), a monocyte chemokine, in mice fed both soy-based diets compared with the CAS-fed mice. These findings paralleled the reduced number of macrophages observed in the lesion site in the aorta of SPI+- or SPI(-)-fed mice compared with CAS-fed mice. In an in vitro LPS-induced inflammation model, soy isoflavones (genistein, daidzein, and equol alone or in combination) dose dependently inhibited LPS-induced MCP-1 secretion by macrophages, suggesting a role for soy isoflavones for the protective in vivo effects. Collectively, these findings suggest that the reduction in atherosclerotic lesions observed in mice fed the soy-based diet is mediated in part by inhibition of MCP-1 that could result in reduced monocyte migration, an early event during atherogenesis.     

Ellagic acid suppresses oxidised low-density lipoprotein-induced aortic smooth muscle cell proliferation: studies on the activation of extracellular signal-regulated kinase 1/2 and proliferating cell nuclear antigen expression

Proliferation of intimal vascular smooth muscle cells is an important component in the development of atherosclerosis. Ellagic acid is a phenolic compound present in fruits (raspberries, blueberries, strawberries) and walnuts. The present study investigated the effect of ellagic acid on the oxidised LDL (ox-LDL)-induced proliferation of rat aortic smooth muscle cells (RASMC). The study found that ellagic acid significantly inhibited ox-LDL-induced proliferation of RASMC and phosphorylation of extracellular signal-regulated kinase (ERK) 1/2. Furthermore, ellagic acid also blocked the ox-LDL-induced (inducible) cell-cycle progression and down regulation of the expression of proliferating cell nuclear antigen (PCNA) in RASMC. Therefore, ellagic acid reduced the amount of ox-LDL-induced proliferation of RASMC via inactivation of the ERK pathway and suppression of PCNA expression. These results may significantly advance the understanding of the role that antioxidants play in the prevention of atherosclerosis.     

Oleic acid induces smooth muscle foam cell formation and enhances atherosclerotic lesion development via CD36

Background  

Elevated plasma free fatty acid (FFA) levels have been linked to the development of atherosclerosis. However, how FFA causes atherosclerosis has not been determined. Because fatty acid translocase (FAT/CD36) is responsible for the uptake of FFA, we hypothesized that the atherogenic effects of FFA may be mediated via CD36.     

Fructose intake increases hyperlipidemia and modifies apolipoprotein expression in apolipoprotein AI-CIII-AIV transgenic mice

Fructose intake has increased steadily during the past two decades. The objective of this study was to determine the effect of fructose intake on lipid metabolism in apolipoprotein (apo) AI-CIII-AIV transgenic (Tg) mice that have severe hypertriglyceridemia and moderate hypercholesterolemia. Tg and control mice were fed for 9 mo a commercial nonpurified diet and had free access to water or 250 g/L fructose solution. In Tg mice, fructose intake increased triglycerides and cholesterol but did not induce insulin resistance. There were no differences in human hepatic apo AI and apo CIII mRNA levels in fructose-fed mice compared with untreated mice, but apo AIV mRNA was greater, indicating a differential expression of the apo AI and apo AIV genes in response to dietary perturbations. Interestingly, the plasma concentration of the three human apolipoproteins was enhanced in fructose-fed Tg mice compared with untreated Tg mice. Our data suggest that long-term fructose consumption had strong adverse effects in this hyperlipidemic mouse model.     

Dietary supplementation with gamma-linolenic acid or fish oil decreases T lymphocyte proliferation in healthy older humans.

Animal and human studies have shown that greatly increasing the amounts of flax seed oil [rich in the (n-3) polyunsaturated fatty acid (PUFA) alpha-linolenic acid (ALNA)] or fish oil [FO; rich in the long chain (n-3) PUFA eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)] in the diet can decrease mitogen-stimulated lymphocyte proliferation. The objective of this study was to determine the effect of dietary supplementation with moderate levels of ALNA, gamma-linolenic acid (GLA), arachidonic acid (ARA), DHA or FO on the proliferation of mitogen-stimulated human peripheral blood mononuclear cells (PBMC) and on the production of cytokines by those cells. The study was randomized, placebo-controlled, double-blinded and parallel. Healthy subjects ages 55-75 y consumed nine capsules/d for 12 wk; the capsules contained placebo oil (an 80:20 mix of palm and sunflower seed oils) or blends of placebo oil with oils rich in ALNA, GLA, ARA or DHA or FO. Subjects in these groups consumed 2 g of ALNA or 770 mg of GLA or 680 mg of ARA or 720 mg of DHA or 1 g of EPA plus DHA (720 mg of EPA + 280 mg of DHA) daily from the capsules. Total fat intake from the capsules was 4 g/d. The fatty acid composition of PBMC phospholipids was significantly changed in the GLA, ARA, DHA and FO groups. Lymphocyte proliferation was not significantly affected by the placebo, ALNA, ARA or DHA treatments. GLA and FO caused a significant decrease (up to 65%) in lymphocyte proliferation. This decrease was partly reversed by 4 wk after stopping the supplementation. None of the treatments affected the production of interleukin-2 or interferon-gamma by PBMC and none of the treatments affected the number or proportion of T or B lymphocytes, helper or cytotoxic T lymphocytes or memory helper T lymphocytes in the circulation. We conclude that a moderate level GLA or EPA but not of other (n-6) or (n-3) PUFA can decrease lymphocyte proliferation but not production of interleukin-2 or interferon-gamma.     

Effect of hyperlipidemia on the expression of circadian genes in apolipoprotein E knock-out atherosclerotic mice

Background  

Circadian patterns of cardiovascular vulnerability were well characterized, with a peak incidence of acute myocardial infarction and stroke secondary to atherosclerosis in the morning, which showed the circadian clock may take part in the pathological process of atherosclerosis induced by hyperlipidemia. Hence, the effect of hyperlipidemia on the expression of circadian genes was investigated in atherosclerotic mouse model.     

Vitamin C and vitamin E antagonistically modulate human vascular endothelial and smooth muscle cell DNA synthesis and proliferation

Summary Background Vitamin C and E are suggested to play a preventive role in the pathogenesis of atherosclerosis. They reduce oxidation of low density lipoproteins (oxLDL), thereby protecting human vascular arterial endothelial and smooth muscle cells from oxLDL induced damages. Aims of the Study Since vascular arterial endothelial and smooth muscle cells are both involved in atherosclerotic plaque formation, we simultaneously examined the effect of vitamin C, E and oxLDL on their DNA synthesis and proliferation to further elucidate their joint role in this process. Methods Human umbilical arterial endothelial cells (HUAEC) and human arterial smooth muscle cells (HUASMC) were incubated with “preventive concentrations” of vitamin C (60μM) and E (30μM) and with LDL (60μg/ml) of increasing oxidation grade. Cell proliferation and DNA synthesis were determined by cell count and [³H]-thymidine uptake, respectively. Results Vitamin C alone or in combination with E increased significantly cell number and [³H]-thymidine uptake in HUAEC. The combination exhibited the strongest effect. In contrast, cell number and [³H]-thymidine uptake in HUASMC were significantly decreased in the presence of vitamin C, vitamin E or its combination. OxLDL (60 μg/ml) inhibited cell number and [³H]-thymidine uptake in HUAECs, the latter in an oxidation-grade dependent manner. In HUASMC oxLDL promoted a higher cell number and [³H]-thymidine uptake. If induced by minimally oxLDL, this reduc-tion or increase could be partially reversed by vitamin C alone or in combination with vitamin E. Conclusion Vitamin C and E, alone or in combination, modulate proliferation and DNA synthesis of human arterial endothelial and muscle cells and this modulation is antagonistic. Thus, vitamin C and E may act “preventive” on atherosclerotic plaque formation in two steps: first reendothelialisation is promoted, then HUASMC growth is inhibited. Received: 23 August 2001, Accepted: 8 January 2002     

Expression of PPARα modifies fatty acid effects on insulin secretion in uncoupling protein-2 knockout mice

The precursor protein, proopiomelanocortin (POMC), produces many biologically active peptides via a series of enzymatic steps in a tissue-specific manner, yielding the melanocyte-stimulating hormones (MSHs), corticotrophin (ACTH) and β-endorphin. The MSHs and ACTH bind to the extracellular G-protein coupled melanocortin receptors (MCRs) of which there are five subtypes. The MC3R and MC4R show widespread expression in the central nervous system (CNS), whilst there is low level expression of MC1R and MC5R. In the CNS, cell bodies for POMC are mainly located in the arcuate nucleus of the hypothalamus and the nucleus tractus solitarius of the brainstem. Both of these areas have well defined functions relating to appetite and food intake. Mouse knockouts (ko) for pomc, mc4r and mc3r all show an obese phenotype, as do humans expressing mutations of POMC and MC4R. Recently, human subjects with specific mutations in β-MSH have been found to be obese too, as have mice with engineered β-endorphin deficiency. The CNS POMC system has other functions, including regulation of sexual behaviour, lactation, the reproductive cycle and possibly central cardiovascular control. However, this review will focus on feeding behaviour and link it in with the neuroanatomy of the POMC neurones in the hypothalamus and brainstem.     

Trans-10, cis-12- and cis-9, trans-11-conjugated linoleic acid isomers selectively modify HDL-apolipoprotein composition in apolipoprotein E knockout mice

Trans-10, cis-12-conjugated linoleic acid (CLA)-enriched diets promote atherosclerosis in mice despite increasing blood concentrations of HDL cholesterol. This suggests that under these conditions, the HDL apolipoproteins (apo) produced are abnormal. To test this hypothesis, apoE-deficient mice were fed a Western-type diet enriched with linoleic acid (control), cis-9, trans-11-CLA or trans-10, cis-12-CLA (1.0% wt/wt) for 12 wk, and the effects on HDL metabolism and apoC-III levels recorded. Compared with the control and cis-9, trans-11-CLA mice, those fed the trans-10, cis-12-CLA diet had significantly higher HDL cholesterol concentrations, and had a higher incidence of hypertriglyceridemia and hepatic steatosis. Plasma apoA-I and paraoxonase concentrations were significantly lower in the trans-10, cis-12-CLA group than in the cis-9, trans-11-CLA group. These reductions were associated with decreased hepatic expression of these proteins and a shift toward lipid-poor apolipoprotein particles. The plasma apoA-II concentration increased with its corresponding mRNA concentration in the liver, and was preferentially bound to HDL in the trans-10, cis-12-CLA mice, thus explaining the increased HDL cholesterol concentrations in this group. Significant, positive associations were found between apoA-II and C-III (r=0.883, P<0.001) and between apoA-II and atherosclerosis (r=0.68, P<0.001). These results indicate that trans-10, cis-12-CLA intake modifies HDL to form a proatherogenic apoA-II containing particle and promotes phenotypic changes compatible with metabolic syndrome. Cis-9, trans-11-CLA does not promote this detrimental effect.     

Dietary carnosic acid suppresses hepatic steatosis formation via regulation of hepatic fatty acid metabolism in high-fat diet-fed mice

In this study, we examined the hepatic anti-steatosis activity of carnosic acid (CA), a phenolic compound of rosemary (Rosmarinus officinalis) leaves, as well as its possible mechanism of action, in a high-fat diet (HFD)-fed mice model. Mice were fed a HFD, or a HFD supplemented with 0.01% (w/w) CA or 0.02% (w/w) CA, for a period of 12 weeks, after which changes in body weight, blood lipid profiles, and fatty acid mechanism markers were evaluated. The 0.02% (w/w) CA diet resulted in a marked decline in steatosis grade, as well as in homeostasis model assessment of insulin resistance (HOMA-IR) index values, intraperitoneal glucose tolerance test (IGTT) results, body weight gain, liver weight, and blood lipid levels (P < 0.05). The expression level of hepatic lipogenic genes, such as sterol regulating element binding protein-1c (SREBP-1c), liver-fatty acid binding protein (L-FABP), stearoyl-CoA desaturase 1 (SCD1), and fatty acid synthase (FAS), was significantly lower in mice fed 0.01% (w/w) CA and 0.02% (w/w) CA diets than that in the HFD group; on the other hand, the expression level of β-oxidation-related genes, such as peroxisome proliferator-activated receptor α (PPAR-α), carnitine palmitoyltransferase 1 (CPT-1), and acyl-CoA oxidase (ACO), was higher in mice fed a 0.02% (w/w) CA diet, than that in the HFD group (P < 0.05). In addition, the hepatic content of palmitic acid (C16:0), palmitoleic acid (C16:1), and oleic acid (C18:1) was significantly lower in mice fed the 0.02% (w/w) CA diet than that in the HFD group (P < 0.05). These results suggest that orally administered CA suppressed HFD-induced hepatic steatosis and fatty liver-related metabolic disorders through decrease of de novo lipogenesis and fatty acid elongation and increase of fatty acid β-oxidation in mice.     

Glyceollins inhibit platelet-derived growth factor-mediated human arterial smooth muscle cell proliferation and migration

Platelet-derived growth factor (PDGF)-BB can induce abnormal proliferation and migration of vascular smooth muscle cells (VSMC) that are involved in the development of CVD. In our preliminary study, phytoalexin glyceollins (glyceollins I, II and III) isolated from soyabean seeds cultured with Aspergillus sojae showed strong antioxidant and anti-inflammatory activity. Since antioxidants showed beneficial effects on chronic inflammatory diseases, the purpose of the present study was to examine the effects of glyceollins on PDGF-induced proliferation and migration in human aortic smooth muscle cells (HASMC). Incubation of resting HASMC with glyceollins for 24?h significantly diminished PDGF-increased cell number and DNA synthesis in a dose-dependent manner without any cytotoxicity. In addition to blocking of the PDGF-inducible progression through the G0/G1 to the S phase of the cell cycle, glyceollins down-regulated the expression of cyclin-dependent kinase (CDK)2 and cyclin D1, and up-regulated the expression of CDK inhibitors such as p27kip1 and p53.Glyceollins also effectively inhibited reactive oxygen species generation and phosphorylation of PDGF receptor-β, phospholipase Cγ1, Akt and extracellular signal-regulated kinase 1/2 by PDGF stimulation. Furthermore, glyceollins were found to inhibit PDGF-induced dissociation of actin filaments and cell migration. Thus, the results suggest that glyceollins could become a potent therapeutic agent for regulating VSMC-associated vascular disease such as atherosclerosis and restenosis after angioplasty.     

Astaxanthin-rich extract from the green alga Haematococcus pluvialis lowers plasma lipid concentrations and enhances antioxidant defense in apolipoprotein E knockout mice

Dyslipidemia and oxidative stress contribute to atherogenesis. Astaxanthin (ASTX) is a red-colored carotenoid well known for its high antioxidant capacity. However, its effects on lipid metabolism and antioxidant defense mechanisms have received only limited investigation. We fed male apoE knockout (apoE)(-/-) mice, a mouse model for atherosclerosis, a high-fat (15%)/high-cholesterol (0.2%) diet alone (control) or supplemented with ASTX-rich Hematococcus pluvialis extract (0.03% ASTX by weight) for 4 wk. ASTX-fed apoE(-/-) mice had significantly lower plasma total cholesterol and TG concentrations than controls, but body weight and plasma alanine aminotransferase and aspartate aminotransferase did not differ between the groups. qRT-PCR analysis demonstrated significantly greater mRNA levels of LDL receptor (LDLR), 3-hydroxy-3-methylglutaryl CoA reductase, and sterol regulatory element binding protein 2 (SREBP-2) and greater mature SREBP-2 protein in the livers of ASTX-fed mice, indicating that increased LDLR expression may be responsible for the hypocholesterolemic effect of ASTX. Hepatic lipogenic gene expression was not altered, but carnitine palmitoyl transferase 1, acetyl-CoA carboxylase β, and acyl-CoA oxidase mRNA abundance were significantly increased by ASTX supplementation, suggesting the TG-lowering effect of ASTX may be due to increased fatty acid β-oxidation in the liver. Expression of the nuclear factor E2 related factor 2-responsive endogenous antioxidant gene also was induced with concomitantly lower glutathione disulfide levels in the livers of ASTX-fed apoE(-/-) mice compared to controls. In conclusion, these results suggest that supplementation of ASTX-rich H. pluvialis extract improves cholesterol and lipid metabolism as well as antioxidant defense mechanisms, all of which could help mitigate the progression of atherosclerosis.     

Conjugated linoleic acid suppresses myogenic gene expression in a model of human muscle cell inflammation

Proinflammatory cytokines, such as tumor necrosis factor (TNF)-alpha, contribute to muscle wasting in inflammatory disorders, where TNFalpha acts to regulate myogenic genes. Conjugated linoleic acid (CLA) has shown promise as an antiproliferative and antiinflammatory agent, leading to its potential as a therapeutic agent in muscle-wasting disorders. To evaluate the effect of CLA on myogenesis during inflammation, human primary muscle cells were grown in culture and exposed to varying concentrations of TNFalpha and the cis-9, trans-11 and trans-10, cis-12 CLA isomers. Expression of myogenic genes (Myf5, MyoD, myogenin, and myostatin) and the functional genes creatine kinase (CK) and myosin heavy chain (MHC IIx) were measured by real-time PCR. TNFalpha significantly downregulated MyoD and myogenin expression, whereas it increased Myf5 expression. These changes corresponded with a decrease in both CK and MHC IIx expression. Both isomers of CLA mimicked the inhibitory effect of TNFalpha treatment on MyoD and myogenin expression, whereas myostatin expression was diminished in the presence of both isomers of CLA either alone or in combination with TNFalpha. Both isomers of CLA decreased CK and MHC IIx expression. These findings demonstrate that TNFalpha can have specific regulatory effects on myogenic genes in primary human muscle cells. A postulated antiinflammatory role of CLA in myogenesis appears more complex, with an indication that CLA may have a negative effect on this process.     

Influence of apolipoprotein E genotype and dietary alpha-tocopherol on redox status and C-reactive protein levels in apolipoprotein E3 and E4 targeted replacement mice

The molecular basis of the positive association between apoE4 genotype and CVD remains unclear. There is direct in vitro evidence indicating that apoE4 is a poorer antioxidant relative to the apoE3 isoform, with some indirect in vivo evidence also available. Therefore it was hypothesised that apoE4 carriers may benefit from alpha-tocopherol (alpha-Toc) supplementation. Targeted replacement mice expressing the human apoE3 and apoE4 were fed with a diet poor (0 mg/kg diet) or rich (200 mg/kg diet) in alpha-Toc for 12 weeks. Neither apoE genotype nor dietary alpha-Toc exerted any effects on the antioxidant defence system, including glutathione, catalase, superoxide dismutase, glutathione peroxidase and glutathione reductase activities. In addition, no differences were observed in mitogen-induced lymphocyte proliferation. alpha-Toc concentrations were modestly higher in plasma and lower in tissues of apoE4 compared with apoE3 mice, with the greatest differences evident in the lung, suggesting that an apoE4 genotype may reduce alpha-Toc delivery to tissues. A tendency towards increased plasma F2-isoprostanes in apoE4 mice was observed, while liver thiobarbituric acid-reactive substances did not differ between apoE3 and apoE4 mice. In addition, C-reactive protein (CRP) concentrations were reduced in apoE4 mice indicating that this positive effect on CRP may in part negate the increased CVD risk associated with an apoE4 genotype.     

Nelumbo nucifera leaf extract inhibits neointimal hyperplasia through modulation of smooth muscle cell proliferation and migration

ObjectiveEndovascular injury induced by balloon withdrawal leads to the increased activation of matrix metalloproteinases (MMPs) in the vascular wall allowing the proliferated smooth muscle cells (SMCs) to digest the surrounding extracellular matrix and migrate from the media into the intima leading to the intimal thickening. The objective of this study was to examine the effect of Nelumbo nucifera leaf extract (NL) on intimal thickening of rat carotid artery injured by balloon catheter and on the proliferation and migration of cultured vascular smooth muscle cells (VSMCs) induced by tumor necrosis factor-α.MethodsNL was administered orally using gastric sonde at three different doses, 100 mg kg^?1 (NL100), 400 mg kg^?1 (NL400), and 800 mg kg^?1 (NL800) for 4 wk from the day of balloon injury in the rats. VSMC proliferation and migration were assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and Boyden chamber methods, whereas enzymatic action of matrix metalloproteinase-2 and -9 (MMP-2 and MMP-9) was carried out by gelatin zymography, and MMP-9 protein expression, extracellular signal-regulated kinase 1/2, and c-Jun N-terminal kinase phosphorylations were assessed by Western blot analyses.ResultsNL reduced the intimal thickening by suppressing VSMC's proliferation through inhibition of extracellular signal-regulated kinase 1/2 phosphorylation and their migration by reducing the expression of MMP-2 and -9 through inhibition of JNK1/2 phosphorylation.ConclusionThus, the results suggest that NL can be considered of therapeutic value in the prevention of atherosclerosis because restenosis after percutaneous transluminal coronary angioplasty can be considered a model of “accelerated atherosclerosis.”     

Dietary oxysterols induce in vivo toxicity of coronary endothelial and smooth muscle cells

Summary Dietary cholesterol oxidation products (COPs) were reported to exhibit in vitro toxicity toward vascular cells. The aim of this study was to determine whether dietary COPs induce in vivo toxicity toward coronary arteries and to evaluate their effect on the coronary reactivity. Golden Syrian hamsters were fed either a normolipidic diet or a hyperlipidic diet with or without a mixture of COPs (1.4 mg/kg/day). At the end of the feeding periods, cardiac mitochondria and cytosol were prepared to determine the subcellular distribution of cytochrome c. Oxidative phosphorylation was evaluated with glutamate, pyruvate or palmitoylcarnitine as a substrate. The main coronary artery was examined all along its length by transmission electron microscopy (TEM). Plasma sterol concentrations were determined. Furthermore, at the end of the 3–month feeding period, the hearts were perfused at constant pressure by the Langendorff method. The endothelium–dependent reactivity to acetylcholine was evaluated. The myocardial sterol concentration was also estimated. After a 15–day diet with dietary COPs, a release of cytochrome c into the cytosolic fraction of the whole heart occurred, which indicated apoptosis of one or several types of cardiac cells probably induced by excess circulating cholestanetriol. The morphological data obtained by TEM after three months of diet suggested that mainly vascular cells (endothelial and smooth muscle cells) were damaged by dietary COPs, whereas cardiomyocytes appeared healthy. Furthermore, the mitochondrial oxidation of palmitoylcarnitine was reduced and that of pyruvate was increased, suggesting some maintenance of energy metabolism. This strengthens the hypothesis of apoptosis. Several changes in coronary reactivity suggesting an increased NO production were observed. In conclusion, dietary COPs triggered in vivo apoptosis of coronary cells through the release of cytochrome c in the cytosol. This toxicity was counterbalanced by an increased endothelium–dependent dilation.