1
|
Zalewski PD, Beltrame JF, Wawer AA, Abdo AI, Murgia C. Roles for endothelial zinc homeostasis in vascular physiology and coronary artery disease. Crit Rev Food Sci Nutr 2018; 59:3511-3525. [PMID: 29999409 DOI: 10.1080/10408398.2018.1495614] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The discovery of the roles of nitric oxide (NO) in cardiovascular signaling has led to a revolution in the understanding of cardiovascular disease. A new perspective to this story involving zinc (Zn) is emerging. Zn and its associated Zn transporter proteins are important for the integrity and functions of both the large conduit vessels and the microvascular resistance vessels. The Zn and NO pathways are tightly coordinated. Zn ions are required for the dimerization of endothelial nitric oxide synthase and subsequent generation of NO while generation of NO leads to a rapid mobilization of endothelial Zn stores. Labile Zn may mediate important downstream actions of NO including vascular cytoprotection and vasodilation. Several vascular disease risk factors (including aging, smoking and diabetes) interfere with Zn homeostatic mechanisms and both hypozincaemia and Zn transporter protein abnormalities are linked to atherosclerosis and microvascular disease. Some vegetarian diets and long-term use of certain anti-hypertensives may also impact on Zn status. The available evidence supports the existence of a Zn regulatory pathway in the vascular wall that is coupled to the generation and actions of NO and which is compromised in Zn deficiency with consequent implications for the pathogenesis and therapy of vascular disease.
Collapse
Affiliation(s)
- P D Zalewski
- Discipline of Medicine, University of Adelaide, The Queen Elizabeth Hospital and the Basil Hetzel Institute for Translational Health Research, Woodville, South Australia
| | - J F Beltrame
- Discipline of Medicine, University of Adelaide, The Queen Elizabeth Hospital and the Basil Hetzel Institute for Translational Health Research, Woodville, South Australia
| | - A A Wawer
- Discipline of Medicine, University of Adelaide, The Queen Elizabeth Hospital and the Basil Hetzel Institute for Translational Health Research, Woodville, South Australia
| | - A I Abdo
- Discipline of Medicine, University of Adelaide, The Queen Elizabeth Hospital and the Basil Hetzel Institute for Translational Health Research, Woodville, South Australia
| | - C Murgia
- Department of Nutrition, Dietetics and Food, Monash University, Melbourne, VIC, Australia
| |
Collapse
|
2
|
Mildner-Szkudlarz S, Bajerska J. Protective effect of grape by-product-fortified breads against cholesterol/cholic acid diet-induced hypercholesterolaemia in rats. JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2013; 93:3271-8. [PMID: 23584744 DOI: 10.1002/jsfa.6171] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2012] [Revised: 01/29/2013] [Accepted: 04/12/2013] [Indexed: 11/06/2022]
Abstract
BACKGROUND New breads fortified with two different forms of grape by-products, namely dried powdered skins (PGP) and freeze-dried extract therefrom (EGP), were characterised and their protective effect against hypercholesterolaemia in rats was studied. RESULTS The phenolic compound profiles of supplemented breads were dominated by epicatechin and catechin together with appreciable amounts of dimeric procyanidins. Sensory evaluation of enhanced breads revealed that a maximum of 6% PGP or 1.4% EGP could be incorporated to prepare acceptable products. Intake of high-cholesterol/cholic acid diet containing 6% PGP- or 1.4% EGP-fortified bread increased fresh stool weight and significantly reduced protein and fat digestion but did not negatively affect animal growth. PGP- and EGP-fortified breads diminished the negative impact of high-cholesterol/cholic acid diet, lowering total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), lipid peroxidation, glucose and leptin levels, preventing visceral fat accumulation and increasing high-density lipoprotein cholesterol and plasma ferric-reducing antioxidant power levels. Since control bread feeding significantly lowered TC, LDL-C and lipid peroxidation compared with high-fat diet, it may suggested that not only grape by-products but also another components in bread were related to lipid metabolism. CONCLUSION These results demonstrate that intake of both PGP- and EGP-fortified sourdough mixed rye breads might contribute to a reduction of cardiovascular risk.
Collapse
Affiliation(s)
- Sylwia Mildner-Szkudlarz
- Department of Food Science and Nutrition, Poznań University of Life Sciences, Ul. Wojska Polskiego 28, PL-60-637, Poznan, Poland
| | | |
Collapse
|
3
|
Thiruchenduran M, Vijayan NA, Sawaminathan JK, Devaraj SN. Protective effect of grape seed proanthocyanidins against cholesterol cholic acid diet-induced hypercholesterolemia in rats. Cardiovasc Pathol 2011; 20:361-8. [DOI: 10.1016/j.carpath.2010.09.002] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/10/2010] [Revised: 08/24/2010] [Accepted: 09/02/2010] [Indexed: 11/28/2022] Open
|
4
|
Conway DE, Lee S, Eskin SG, Shah AK, Jo H, McIntire LV. Endothelial metallothionein expression and intracellular free zinc levels are regulated by shear stress. Am J Physiol Cell Physiol 2010; 299:C1461-7. [PMID: 20861469 DOI: 10.1152/ajpcell.00570.2009] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
We examined the effects of fluid shear stress on metallothionein (MT) gene and protein expression and intracellular free zinc in mouse aorta and in human umbilical vein endothelial cells (HUVECs). Immunostaining of the endothelial surface of mouse aorta revealed increased expression of MT protein in the lesser curvature of the aorta relative to the descending thoracic aorta. HUVECs were exposed to high steady shear stress (15 dyn/cm(2)), low steady shear stress (1 dyn/cm(2)), or reversing shear stress (mean of 1 dyn/cm(2), 1 Hz) for 24 h. Gene expression of three MT-1 isoforms, MT-2A, and zinc transporter-1 was upregulated by low steady shear stress and reversing shear stress. HUVECs exposed to 15 dyn/cm(2) had increased levels of free zinc compared with cells under other shear stress regimes and static conditions. The increase in free zinc was partially blocked with an inhibitor of nitric oxide synthesis, suggesting a role for shear stress-induced endothelial nitric oxide synthase activity. Cells subjected to reversing shear stress in zinc-supplemented media (50 μM ZnSO(4)) had increased intracellular free zinc, reduced surface intercellular adhesion molecule-1 expression, and reduced monocyte adhesion compared with cells exposed to reversing shear stress in normal media. The sensitivity of intracellular free zinc to differences in shear stress suggests that intracellular zinc levels are important in the regulation of the endothelium and in the progression of vascular disease.
Collapse
Affiliation(s)
- Daniel E Conway
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University School of Medicine, Atlanta, Georgia 30332-0535, USA
| | | | | | | | | | | |
Collapse
|
5
|
Makni M, Fetoui H, Gargouri NK, Garoui EM, Jaber H, Makni J, Boudawara T, Zeghal N. Hypolipidemic and hepatoprotective effects of flax and pumpkin seed mixture rich in omega-3 and omega-6 fatty acids in hypercholesterolemic rats. Food Chem Toxicol 2008; 46:3714-20. [PMID: 18938206 DOI: 10.1016/j.fct.2008.09.057] [Citation(s) in RCA: 96] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2008] [Revised: 09/12/2008] [Accepted: 09/22/2008] [Indexed: 11/29/2022]
Abstract
Flax and pumpkin seeds are a rich source of unsaturated fatty acids, antioxidants and fibers, known to have anti-atherogenic and hepatoprotective activities. These effects were evaluated in Wistar rats fed with 1% cholesterol diet. The study was performed on 30 male rats divided into three groups: a control group (CD), CD-chol group fed diet with 1% cholesterol and MS-chol group fed diet enriched with flax and pumpkin seed mixture. In CD-chol group, total cholesterol TC, triacylglycerol TG in plasma and liver, plasma LDL-C, atherogenic index AI and LDL/HDL ratio significantly increased. In MS-chol group lipid parameters decreased significantly, plasma and liver fatty acid composition showed an increase of PUFAs (ALA and LA), and MUFAs (oleic and eicosaenoic acid) and a decrease of SFA (palmitic and stearic acid). In plasma and liver of MS-chol group, malondialdehyde levels decreased and the efficiency of antioxidant defense system was improved compared to CD-chol group. Liver histological sections showed lipid storage in hepatocytes of CD-chol group and an improvement was noted in MS-chol group. Our results suggested that flax and pumpkin seed mixture had anti-atherogenic and hepatoprotective effects which were probably mediated by unsaturated fatty acids present in seed mixture.
Collapse
Affiliation(s)
- M Makni
- Animal Physiology Laboratory, Sciences Faculty, UR 08-73, BP 1171, Tunisia
| | | | | | | | | | | | | | | |
Collapse
|
6
|
Bouderbala S, Lamri-Senhadji M, Prost J, Lacaille-Dubois MA, Bouchenak M. Changes in antioxidant defense status in hypercholesterolemic rats treated with Ajuga iva. PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2008; 15:453-461. [PMID: 18068964 DOI: 10.1016/j.phymed.2007.10.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
The aim of the study was to investigate the effect of aqueous extract of Ajuga iva (Ai) on serum and tissues lipid peroxidation as well as antioxidant enzymes activities in red blood cells (RBC) and tissues, in high hypercholesterolemic rats (HC). Male Wistar rats (n=12) were fed on 1% cholesterol-enriched diet for 15d. After this adaptation phase, hypercholesterolemic rats (total cholesterol=6.5+/-0.6mol/l) were divided into two groups fed the same diet and treated or not with Ai for 15d. Thiobarbituric acid reactive substances (TBARS) concentrations in serum, LDL-HDL(1), HDL(2) and HDL(3) were respectively, 5-, 7.8-, 2.3- and 5-fold lower in Ai treated than untreated hypercholesterolemic groups. TBARS concentrations were 1.4-fold lower in heart and 2.8-fold higher in kidney in Ai-HC treated than untreated HC group. Superoxide dismutase activity was respectively, 1.2- and 1.4-fold higher in RBC and muscle in Ai treated than untreated group. In RBC, Ajuga iva treatment enhanced glutathione peroxidase (GSH-Px) (+9%) and glutathione reductase (GSSH-Red) (+12%) in Ai-HC treated than untreated HC group. GSSH-Red activity was 1.4- and 1.5-fold higher in adipose tissue and heart, respectively and 3.7-fold lower in kidney in Ai treated than untreated group. Liver catalase activity was 1.6-fold higher in Ai treated than untreated group. Adipose tissue and muscle total glutathione content represented in Ai treated group 35% and 36% of the value noted in untreated group. Nitric oxide values of liver, adipose tissue and heart were 3.3-, 2.5- and 3.4-fold higher in Ai-HC than HC group. Ajuga iva treatment enhanced alpha-tocopherol contents (+25%) in Ai treated than untreated group. In conclusion, Ajuga iva treatment is more effective to improve the antioxidant capacity of RBC than that of tissues. Indeed, Ai is able to reduce the oxidative stress in hypercholesterolemic rats by increasing the antioxidant enzymes activity.
Collapse
Affiliation(s)
- S Bouderbala
- Laboratoire de Nutrition Clinique et Métabolique, Département de Biologie, Faculté des Sciences, Université d'Oran Es-Sénia, 31000 Oran, Algeria
| | | | | | | | | |
Collapse
|
7
|
Stadler N, Stanley N, Heeneman S, Vacata V, Daemen MJ, Bannon PG, Waltenberger J, Davies MJ. Accumulation of Zinc in Human Atherosclerotic Lesions Correlates With Calcium Levels But Does Not Protect Against Protein Oxidation. Arterioscler Thromb Vasc Biol 2008; 28:1024-30. [DOI: 10.1161/atvbaha.108.162735] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Objective—
Oxidized lipids and proteins, as well as decreased antioxidant levels, have been detected in human atherosclerotic lesions, with oxidation catalyzed by iron and copper postulated to contribute to lesion development. Zinc has been postulated to displace iron from critical sites and thereby protect against damage. In this study, metal ion and protein oxidation levels were quantified in human carotid and abdominal artery specimens containing early-to-advanced lesions, to determine whether zinc concentrations correlate inversely with iron levels and protein oxidation.
Methods and Results—
Metal ions were quantified by EPR and inductively coupled plasma mass spectroscopy. Native and oxidized protein side-chains were quantified by high-performance liquid chromatography. Elevated levels of zinc (≈6-fold) were detected in advanced lesions compared to healthy tissue or early lesions. Zinc did not correlate negatively with iron or copper levels suggesting that zinc does not displace these metal ions. Highly significant positive correlations (
P
<0.005) were detected between zinc and calcium levels.
Conclusions—
Zinc did not correlate with low iron levels and reduced protein oxidation. These data indicate that zinc does not prevent protein oxidation in advanced lesions. The reported protective effect of zinc accumulation is proposed to be associated with lesion calcification.
Collapse
Affiliation(s)
- Nadina Stadler
- From the Heart Research Institute (N. Stadler, N. Stanley, M.J.D.), Sydney, Australia; the Cardiovascular Research Institute Maastricht (CARIM) (N. Stadler, S.H., M.J.A.P.D., J.W.), Maastricht, The Netherlands; Gemeinschaftspraxis für Laboratoriumsmedizin (V.V.), Leverkusen, Germany; and the Baird Institute for Heart and Lung Surgical Research (P.G.B.), Sydney, Australia
| | - Naomi Stanley
- From the Heart Research Institute (N. Stadler, N. Stanley, M.J.D.), Sydney, Australia; the Cardiovascular Research Institute Maastricht (CARIM) (N. Stadler, S.H., M.J.A.P.D., J.W.), Maastricht, The Netherlands; Gemeinschaftspraxis für Laboratoriumsmedizin (V.V.), Leverkusen, Germany; and the Baird Institute for Heart and Lung Surgical Research (P.G.B.), Sydney, Australia
| | - Sylvia Heeneman
- From the Heart Research Institute (N. Stadler, N. Stanley, M.J.D.), Sydney, Australia; the Cardiovascular Research Institute Maastricht (CARIM) (N. Stadler, S.H., M.J.A.P.D., J.W.), Maastricht, The Netherlands; Gemeinschaftspraxis für Laboratoriumsmedizin (V.V.), Leverkusen, Germany; and the Baird Institute for Heart and Lung Surgical Research (P.G.B.), Sydney, Australia
| | - Vladimir Vacata
- From the Heart Research Institute (N. Stadler, N. Stanley, M.J.D.), Sydney, Australia; the Cardiovascular Research Institute Maastricht (CARIM) (N. Stadler, S.H., M.J.A.P.D., J.W.), Maastricht, The Netherlands; Gemeinschaftspraxis für Laboratoriumsmedizin (V.V.), Leverkusen, Germany; and the Baird Institute for Heart and Lung Surgical Research (P.G.B.), Sydney, Australia
| | - Mat J.A.P. Daemen
- From the Heart Research Institute (N. Stadler, N. Stanley, M.J.D.), Sydney, Australia; the Cardiovascular Research Institute Maastricht (CARIM) (N. Stadler, S.H., M.J.A.P.D., J.W.), Maastricht, The Netherlands; Gemeinschaftspraxis für Laboratoriumsmedizin (V.V.), Leverkusen, Germany; and the Baird Institute for Heart and Lung Surgical Research (P.G.B.), Sydney, Australia
| | - Paul G. Bannon
- From the Heart Research Institute (N. Stadler, N. Stanley, M.J.D.), Sydney, Australia; the Cardiovascular Research Institute Maastricht (CARIM) (N. Stadler, S.H., M.J.A.P.D., J.W.), Maastricht, The Netherlands; Gemeinschaftspraxis für Laboratoriumsmedizin (V.V.), Leverkusen, Germany; and the Baird Institute for Heart and Lung Surgical Research (P.G.B.), Sydney, Australia
| | - Johannes Waltenberger
- From the Heart Research Institute (N. Stadler, N. Stanley, M.J.D.), Sydney, Australia; the Cardiovascular Research Institute Maastricht (CARIM) (N. Stadler, S.H., M.J.A.P.D., J.W.), Maastricht, The Netherlands; Gemeinschaftspraxis für Laboratoriumsmedizin (V.V.), Leverkusen, Germany; and the Baird Institute for Heart and Lung Surgical Research (P.G.B.), Sydney, Australia
| | - Michael J. Davies
- From the Heart Research Institute (N. Stadler, N. Stanley, M.J.D.), Sydney, Australia; the Cardiovascular Research Institute Maastricht (CARIM) (N. Stadler, S.H., M.J.A.P.D., J.W.), Maastricht, The Netherlands; Gemeinschaftspraxis für Laboratoriumsmedizin (V.V.), Leverkusen, Germany; and the Baird Institute for Heart and Lung Surgical Research (P.G.B.), Sydney, Australia
| |
Collapse
|
8
|
Yi X, Maeda N. alpha-Lipoic acid prevents the increase in atherosclerosis induced by diabetes in apolipoprotein E-deficient mice fed high-fat/low-cholesterol diet. Diabetes 2006; 55:2238-44. [PMID: 16873686 DOI: 10.2337/db06-0251] [Citation(s) in RCA: 87] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Considerable evidence indicates that hyperglycemia increases oxidative stress and contributes to the increased incidence of atherosclerosis and cardiovascular complications in diabetic patients. To examine the effect of alpha-lipoic acid, a potent natural antioxidant, on atherosclerosis in diabetic mice, 3-month-old apolipoprotein (apo) E-deficient (apoE(-/-)) mice were made diabetic by administering streptozotocin (STZ). At 4 weeks after starting the STZ administration, a high-fat diet with or without alpha-lipoic acid (1.65 g/kg) was given to the mice and to nondiabetic apoE(-/-) controls. At 20 weeks, markers of oxidative stress were significantly lower in both the diabetic apoE(-/-) mice and their nondiabetic apoE(-/-) controls with alpha-lipoic acid supplement than in those without it. Remarkably, alpha-lipoic acid completely prevented the increase in plasma total cholesterol, atherosclerotic lesions, and the general deterioration of health caused by diabetes. These protective effects of alpha-lipoic acid were accompanied by a reduction of plasma glucose and an accelerated recovery of insulin-producing cells in the pancreas, suggesting that part of its effects are attributable to protecting pancreatic beta-cells from damage. Our results suggest that dietary alpha-lipoic acid is a promising protective agent for reducing cardiovascular complications of diabetes.
Collapse
Affiliation(s)
- Xianwen Yi
- Department of Pathology and Laboratory Medicine, University of North Carolina at Chapel Hill, 701 Brinkhous-Bullitt Bldg., 27599-7525, USA
| | | |
Collapse
|
9
|
Kumar SA, Sudhahar V, Varalakshmi P. Attenuation of serum lipid abnormalities and cardiac oxidative stress by eicosapentaenoate-lipoate (EPA-LA) derivative in experimental hypercholesterolemia. Clin Chim Acta 2005; 355:197-204. [PMID: 15820496 DOI: 10.1016/j.cccn.2005.01.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2004] [Revised: 01/03/2005] [Accepted: 01/05/2005] [Indexed: 01/10/2023]
Abstract
BACKGROUND Dietary cholesterol plays an important role in development of atherogenesis and cardiovascular disease. We explored the lipemic-oxidative injury in the hypercholesterolemic atherogenic animals. The effects of eicosapentaenoic acid (EPA), dl-alpha-lipoic acid (LA) and eicosapentaenoate-lipoate derivative (EPA-LA) were tested for their efficacy in controlling the atherogenic disturbances. METHODS Four groups of male Wistar rats were fed with a high cholesterol diet (rat chow supplemented with 4% cholesterol and 1% cholic acid; HCD) for 30 days. Of these groups, 3 groups of rats were treated with either EPA (oral gavage, 35 mg/kg body weight/day), LA (oral gavage, 20 mg/kg body weight/day) or EPA-LA derivative (oral gavage, 50 mg/kg body weight/day) from 16th day to 30th day of the experimental period. RESULTS HCD induced abnormal increase in lipid peroxidation and serum cholesterol, triglyceride, LDL and VLDL, and a decreased HDL concentration. Altered activity of cardiac and serum creatine kinase, accompanied by a depressed cardiac enzymatic and nonenzymatic antioxidants defense system were observed in HCD fed rats. These changes were partially restored in the EPA and LA treated groups, however, their combined derivative EPA-LA more effectively restored the altered parameters near to that of control (P<0.05). CONCLUSION Lipid abnormalities and oxidative injury were induced by a hypercholesterolemic diet. Administration of the combination treatment of EPA-LA afforded protection against the lipemic-oxidative injury.
Collapse
Affiliation(s)
- Sekar Ashok Kumar
- Department of Medical Biochemistry, Dr. ALM. Post Graduate Institute of Basic Medical Sciences, University of Madras, Taramani Campus, Chennai-600 113, India
| | | | | |
Collapse
|
10
|
Weinberg PD. Analysis of the variable effect of dietary vitamin E supplements on experimental atherosclerosis. JOURNAL OF PLANT PHYSIOLOGY 2005; 162:823-33. [PMID: 16008111 DOI: 10.1016/j.jplph.2005.04.016] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Vitamin E inhibits processes thought to be important in the development of atherosclerosis but clinical trials to determine its effect on cardiovascular disease have given variable results, the majority being negative. The reasons for this are unclear. Animal trials can be better controlled and use more rigorous measures of lesion progression than human trials. The present study reviewed trials using rabbits and mice to determine whether they also are variable and, if so, to uncover methodological differences that may account for the different outcomes. A large number of trials examining the effect of vitamin E supplements on experimental atherosclerosis were identified. Using rigorous selection criteria, a well-defined group was selected for further investigation. Almost all the mice trials showed a significant effect of vitamin E, but only around one-third of the rabbit trials did so. When the rabbit trials were divided into those that did and those that did not observe significant effects, no single factor was found that could account for the dichotomy. However, when the percentage reduction in disease was considered, rather than the within-trial significance level, there were clear dose-dependent effects of vitamin E on disease severity in heritable hyperlipidaemic rabbits, and in genetically normal rabbits made hyperlipidaemic with cholesterol alone; the dose dependence was different in the two groups, the heritable hyperlipidaemic rabbits showing a near ten-fold lower sensitivity. The high doses required to affect experimental atherosclerosis may, if applicable to other species, help explain the absence of effects in many human trials.
Collapse
Affiliation(s)
- Peter D Weinberg
- Physiological Flow Studies Group, Department of Bioengineering, Imperial College London, London SW7 2AZ, UK.
| |
Collapse
|
11
|
Gavrila D, Li WG, McCormick ML, Thomas M, Daugherty A, Cassis LA, Miller FJ, Oberley LW, Dellsperger KC, Weintraub NL. Vitamin E inhibits abdominal aortic aneurysm formation in angiotensin II-infused apolipoprotein E-deficient mice. Arterioscler Thromb Vasc Biol 2005; 25:1671-7. [PMID: 15933246 PMCID: PMC3974107 DOI: 10.1161/01.atv.0000172631.50972.0f] [Citation(s) in RCA: 139] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
BACKGROUND Abdominal aortic aneurysms (AAAs) in humans are associated with locally increased oxidative stress and activity of NADPH oxidase. We investigated the hypothesis that vitamin E, an antioxidant with documented efficacy in mice, can attenuate AAA formation during angiotensin II (Ang II) infusion in apolipoprotein E-deficient mice. METHODS AND RESULTS Six-month-old male apolipoprotein E-deficient mice were infused with Ang II at 1000 ng/kg per minute for 4 weeks via osmotic minipumps while consuming either a regular diet or a diet enriched with vitamin E (2 IU/g of diet). After 4 weeks, abdominal aortic weight and maximal diameter were determined, and aortic tissues were sectioned and examined using biochemical and histological techniques. Vitamin E attenuated formation of AAA, decreasing maximal aortic diameter by 24% and abdominal aortic weight by 34% (P<0.05, respectively). Importantly, animals treated with vitamin E showed a 44% reduction in the combined end point of fatal+nonfatal aortic rupture (P<0.05). Vitamin E also decreased aortic 8-isoprostane content (a marker of oxidative stress) and reduced both aortic macrophage infiltration and osteopontin expression (P<0.05, respectively). Vitamin E treatment had no significant effect on the extent of aortic root atherosclerosis, activation of matrix metalloproteinases 2 or 9, serum lipid profile, or systolic blood pressure. CONCLUSIONS Vitamin E ameliorates AAAs and reduces the combined end point of fatal+nonfatal aortic rupture in this animal model. These findings are consistent with the concept that oxidative stress plays a pivotal role in Ang II-driven AAA formation in hyperlipidemic mice.
Collapse
Affiliation(s)
- Dan Gavrila
- Department of Internal Medicine, University of Iowa, Iowa City, IA, USA
| | | | | | | | | | | | | | | | | | | |
Collapse
|
12
|
McCarty MF. A taurine-supplemented vegan diet may blunt the contribution of neutrophil activation to acute coronary events. Med Hypotheses 2005; 63:419-25. [PMID: 15288360 DOI: 10.1016/j.mehy.2004.03.040] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2004] [Accepted: 03/17/2004] [Indexed: 11/18/2022]
Abstract
Neutrophils are activated in the coronary circulation during acute coronary events (unstable angina and myocardial infarction), often prior to the onset of ischemic damage. Moreover, neutrophils infiltrate coronary plaque in these circumstances, and may contribute to the rupture or erosion of this plaque, triggering thrombosis. Activated neutrophils secrete proteolytic enzymes in latent forms which are activated by the hypochlorous acid (HOCl) generated by myeloperoxidase. These phenomena may help to explain why an elevated white cell count has been found to be an independent coronary risk factor. Low-fat vegan diets can decrease circulating leukocytes--neutrophils and monocytes--possibly owing to down-regulation of systemic IGF-I activity. Thus, a relative neutropenia may contribute to the coronary protection afforded by such diets. However, vegetarian diets are devoid of taurine - the physiological antagonist of HOCl--and tissue levels of this nutrient are relatively low in vegetarians. Taurine has anti-atherosclerotic activity in animal models, possibly reflecting a role for macrophage-derived myeloperoxidase in the atherogenic process. Taurine also has platelet-stabilizing and anti-hypertensive effects that presumably could reduce coronary risk. Thus, it is proposed that a taurine-supplemented low-fat vegan diet represents a rational strategy for diminishing the contribution of activated neutrophils to acute coronary events; moreover, such a regimen would work in a number of other complementary ways to promote cardiovascular health. Moderate alcohol consumption, the well-tolerated drug pentoxifylline, and 5-lipoxygenase inhibitors--zileuton, boswellic acids, fish oil--may also have potential in this regard.
Collapse
Affiliation(s)
- Mark F McCarty
- NutriGuard Research, 1051 Hermes Ave., Encinitas, CA 92024, USA.
| |
Collapse
|
13
|
Abstract
Epidemiological and biochemical studies infer that oxidative processes, including the oxidation of low-density lipoprotein (LDL), are involved in atherosclerosis. Vitamin E has been the focus of several large supplemental studies of cardiovascular disease, yet its potential to attenuate or even prevent atherosclerosis has not been realised. The scientific rationale for vitamin E supplements protecting against atherosclerosis is based primarily on the oxidation theory of atherosclerosis, the assumption that vitamin E becomes depleted as disease progresses, and the expectation that vitamin E prevents the oxidation of LDL in vivo and atherogenic events linked to such oxidation. However, it is increasingly clear that the balance between vitamin E and other antioxidants may be crucial for in vivo antioxidant protection, that vitamin E is only minimally oxidised and not deficient in atherosclerotic lesions, and that vitamin E is not effective against two-electron oxidants that are increasingly implicated in both early and later stages of the disease. It also remains unclear as to whether oxidation plays a bystander or a casual role in atherosclerosis. This lack of knowledge may explain the ambivalence of vitamin E and other antioxidant supplementation in atherosclerosis.
Collapse
Affiliation(s)
- Joanne M Upston
- Centre for Vascular Research, School of Medical Sciences, University of New South Wales, UNSW Sydney, NSW 2052, Australia
| | | | | |
Collapse
|
14
|
Schwenke DC, Rudel LL, Sorci-Thomas MG, Thomas MJ. Alpha-tocopherol protects against diet induced atherosclerosis in New Zealand white rabbits. J Lipid Res 2002; 43:1927-38. [PMID: 12401892 DOI: 10.1194/jlr.m200261-jlr200] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
In this study, we asked the question "does alpha-tocopherol supplementation prevent an increase in total plasma cholesterol (TPC) concentration and reduce the deposition of cholesterol in arterial plaques of rabbits fed atherogenic diets?" Isocaloric diets containing 0.1% cholesterol to induce atherosclerosis were enriched in one of three fats: saturated fats (SAT), monounsaturated fats (MONO), or n-6 polyunsaturated fats (POLY). Half of each of the three diets were supplemented with 2,500 IU alpha-tocopherol/kg-diet. Unsupplemented diets contained 25 IU alpha-tocopherol/kg-diet. Rabbits supplemented with alpha-tocopherol had plasma alpha-tocopherol concentrations 10-fold higher and an average TPC concentration 31% lower, P = 0.017, than rabbits fed unsupplemented diets. Among the three fat-fed groups, the difference was greatest for the POLY fat fed group (54%, P = 0.041). POLY fat-fed rabbits without alpha-tocopherol supplementation had plasma HDL cholesterol concentrations that were less than half that of rabbits fed other fats, P < or = 0.0001. In general, differences in mean esterified artery cholesterol concentrations among the three fat-fed groups, with and without alpha-tocopherol supplementation, paralleled differences in TPC concentration among the groups. This study suggests that for rabbits fed high pharmacological doses of alpha-tocopherol, atherosclerosis can be diminished in situations where the plasma cholesterol concentrations are also significantly lower.
Collapse
Affiliation(s)
- Dawn C Schwenke
- Department of Pathology, Wake Forest University School of Medicine, Winston-Salem, NC, USA
| | | | | | | |
Collapse
|
15
|
Lee MK, Bok SH, Jeong TS, Moon SS, Lee SE, Park YB, Choi MS. Supplementation of naringenin and its synthetic derivative alters antioxidant enzyme activities of erythrocyte and liver in high cholesterol-fed rats. Bioorg Med Chem 2002; 10:2239-44. [PMID: 11983521 DOI: 10.1016/s0968-0896(02)00059-7] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The antioxidative effects of naringenin (1) and its synthetic derivative, naringenin 7-O-cetyl ether (2), were tested. Male rats were fed a 1 g/100 g high-cholesterol diet for 6 weeks with supplements of either 1 or 2 (0.073 mmol/100 g diet) to study the effects on the antioxidant enzyme activities in the erythrocyte and liver. The erythrocyte catalase (CAT) and superoxide dismutase (SOD) activities were significantly higher in the compounds 1 or 2 supplemented groups than in the control group, whereas the hepatic SOD and CAT activities were significantly lower in the compound 2 supplemented group. The compounds 1 and 2 supplements to a high cholesterol diet lowered or tended to lower the plasma TBARS levels, that is, lipid peroxide products, while enhancing the plasma paraoxonase activity. These results indicate that the supplementation of 1 and 2 was effective in improving the antioxidant capacity of the erythrocyte and liver, plus the synthetic functional compound 2 appeared to be as potent as 1 in enhancing the antioxidant defense system.
Collapse
Affiliation(s)
- Mi-Kyung Lee
- Department of Food Science and Nutrition, Kyungpook National University, Taegu, South Korea
| | | | | | | | | | | | | |
Collapse
|
16
|
Yousef MI, El-Hendy HA, El-Demerdash FM, Elagamy EI. Dietary zinc deficiency induced-changes in the activity of enzymes and the levels of free radicals, lipids and protein electrophoretic behavior in growing rats. Toxicology 2002; 175:223-34. [PMID: 12049850 DOI: 10.1016/s0300-483x(02)00049-5] [Citation(s) in RCA: 116] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Zinc (Zn) is an essential nutrient that is required in humans and animals for many physiological functions, including immune and antioxidant function, growth and reproduction. The present study was conducted to investigate the effects of adequate Zn level (38 mg/kg diet, as a control) and two low levels that create Zn deficiencies (19 mg/kg diet, 1/2 of the control and 3.8 mg/kg diet, 1/10 of the control) in growing male and female rats for 10 weeks. To evaluate the effects of these levels, the concentrations of thiobarbituric acid-reactive substances (TBARS), biochemical parameters and protein pattern were studied. Lipid peroxidation in liver, brain and testes of rats fed Zn-deficient diet was indicated by increased TBARS. Serum, liver, brain and testes glutathione S-transferase (GST) activities were significantly (P<0.05) increased in Zn-deficient rats, the effect was pronounced in rats fed the lowest level of Zn (1/10 of control). The activity of lactate dehydrogenase (LDH) was significantly (P<0.05) increased in liver, brain and testes, but decreased in serum in a dose-dependent manner. Zinc deficiency increased (P<0.05) liver aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activities in a dose-dependent manner, while there was no effect on the activity of these enzymes in testes. Zinc deficiency resulted in a significant (P<0.05) decrease in the activity of alkaline phosphatase (AlP) in serum and liver in a dose-dependent manner, but no effect in testes was found. The activity of acid phosphatase (AcP) was not affected in serum, liver and testes. Zn-deficient rats had higher liver concentrations of total lipids (TL), cholesterol, triglyceride (TG), and low density lipoprotein (LDL), while high density lipoprotein (HDL) was significantly (P<0.05) declined in a dose-dependent manner. Brain and serum acetylcholinesterase (AChE) activities were, however, not affected (P<0.05) by Zn deficiency. Protein content in liver, brain and testes showed a significant (P<0.05) decrease in rats fed the lowest level of Zn (1/10 of control). Polyacrylamide gel electrophoresis (native-PAGE) of serum proteins revealed that the intensity of immunoglobulins, serum albumin as well as several peptide bands were decreased in rats fed 1/2 or 1/10 of Zn adequate, i.e. their synthesis was affected and it was pronounced with the lowest level of Zn deficiency (1/10 of control). However, no clear effect on the transferrin was observed in both cases compared to controls. From the results of this study it can be concluded that Zn deficiency exerts numerous alterations in the studied biochemical parameters, protein pattern, and increased lipid peroxidation.
Collapse
Affiliation(s)
- M I Yousef
- Department of Environmental Studies, Institute of Graduate Studies and Research, Alexandria University, 163 Horreya Avenue, P.O. Box 832, Alexandria 21526, Egypt
| | | | | | | |
Collapse
|
17
|
Ferré N, Camps J, Paul A, Cabré M, Calleja L, Osada J, Joven J. Effects of high-fat, low-cholesterol diets on hepatic lipid peroxidation and antioxidants in apolipoprotein E-deficient mice. Mol Cell Biochem 2001; 218:165-9. [PMID: 11330832 DOI: 10.1023/a:1007296919243] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The present study describes the effects of several high-fat low-cholesterol antiatherogenic diets on the hepatic lipid peroxidation and hepatic antioxidant systems in apolipoprotein E-deficient mice. Eighty mice were distributed into five groups and fed with regular mouse chow or chow supplemented with coconut, palm, olive and sunflower seed oils. After ten weeks, they were sacrificed and the livers were removed so that lipid peroxidation and alpha-tocopherol concentrations, and superoxide dismutase, glutathione peroxidase and glutathione reductase activities could be measured. The size of the atherosclerotic lesions in the aortas was also measured. Results showed that the diets supplemented with olive oil, palm oil or sunflower seed oil significantly decreased the size of the lesion. However, there was an association between those mice that were on diets supplemented with palm or coconut oils and a significant increase in hepatic lipid peroxidation. This association was not found in animals fed with olive or sunflower seed oils, the diets with the highest content of vitamin E. The dietary content of vitamin E was significantly correlated (r = 0.98; p < 0.05) with the hepatic concentration of this compound. Our study suggests that the high content of vitamin E in olive oil or sunflower seed oil may protect from the undesirable hepatotoxic effects of high-fat diets in apo E-deficient mice and that this should be taken into account when these diets are used to prevent atherosclerosis.
Collapse
Affiliation(s)
- N Ferré
- Centre de Recerca Biomèdica, Hospital Universitari de Sant Joan, Cantalunya, Spain
| | | | | | | | | | | | | |
Collapse
|