101
|
Visualization of Inflammation at Early Stage of Lung Cancer in Xenografted Temporally Immunosuppression Rats by Ferrioxamine Magnetic Resonance Imaging. INTERNATIONAL JOURNAL OF MOLECULAR IMAGING 2017; 2016:8434308. [PMID: 28074158 PMCID: PMC5198258 DOI: 10.1155/2016/8434308] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/17/2016] [Accepted: 09/26/2016] [Indexed: 11/25/2022]
Abstract
Physiological responses such as chronic inflammation and angiogenesis could be used as biomarkers for early detection of cancer with noninvasive imaging modalities. The present study reports the application of magnetic resonance imaging instrument to image the binding of ferrioxamine with hemin that allows visualizing the chronic inflammation foci of lung tissue of immunocompromised rats xenografted using small cell lung carcinoma. A low concentration of ferrioxamine (0.05 ± 0.02 μM·kg−1 of rat weight) deposited on tissue outside the vasculature was found to diffuse across the capillary walls to the interstitial space and inflammation foci, which provided a clear enhancement of T1-weighted gradient-echo sequence images. Ferrioxamine imaging allowed the determination of inflammatory sites and their localization in 3D fat-suppressed maximum intensity projections. The smallest dimension of foci that can be clearly determined is about 0.1 mm3. In concomitant to the in vivo imaging, analysis of histological tissue section showed the development of inflammatory sites. This study provides evidence that medical imaging instrument such as MRI scanner allows researchers to correlate images taken with MRI with those using high-resolution microscopy. Moreover, ferrioxamine is a useful molecular probe for determining chronic inflammation particularly at the very early stages of cancer.
Collapse
|
102
|
Arachidonic acid causes hidden blood loss-like red blood cell damage through oxidative stress reactions. J Surg Res 2016; 211:14-20. [PMID: 28501110 DOI: 10.1016/j.jss.2016.11.060] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2016] [Revised: 10/12/2016] [Accepted: 11/30/2016] [Indexed: 01/31/2023]
Abstract
BACKGROUND Hidden blood loss (HBL) often occurs in the prosthetic replacement for joint, but the mechanism is still not clear. MATERIALS AND METHODS This study tried to establish an animal model of HBL by injecting arachidonic acid (AA) into the Sprague-Dawley rats. Different concentrations of AA were injected into the tail veins of the rats, and blood samples were collected before and after administration at 24, 48, and 72 h. A complete blood count was obtained by to find the hemoglobin (Hb) and red blood cell (RBC) count changes. The glutathione peroxidase (GSH-PX) and total superoxide dismutase (T-SOD) activities and hydrogen peroxide (H2O2) levels were detected. The morphological changes of erythrocyte were observed under a polarizing microscope. The absorbance values of the blood samples were tested to determine the presence of ferryl Hb. RESULTS HBL occurred in the experimental groups when the concentration of AA reached 10 mmol/L; Hb and RBC values decreased sharply at 24- and 48-h postinjection. This was followed by reduced activities of GSH-PX and T-SOD and decreased levels of H2O2. Moreover, the pathologic changes of red cell morphology mainly presented as pleomorphic RBC morphology, including cell rupture. The absorbance values of the blood samples were in accordance with ferryl Hb features. RBC and Hb values were relatively stable at 72 h. The GSH-PX and T-SOD activities and H2O2 levels gradually increased up to a balanced state. CONCLUSIONS The study concluded that high concentrations of AA can induce oxidative stress reactions in the body, causing acute injury of RBCs, which is closely related to HBL.
Collapse
|
103
|
Terzian Z, Gasser TC, Blackwell F, Hyafil F, Louedec L, Deschildre C, Ghodbane W, Dorent R, Nicoletti A, Morvan M, Nejjari M, Feldman L, Pavon-Djavid G, Michel JB. Peristrut microhemorrhages: a possible cause of in-stent neoatherosclerosis? Cardiovasc Pathol 2016; 26:30-38. [PMID: 27865168 DOI: 10.1016/j.carpath.2016.08.007] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/22/2016] [Revised: 08/25/2016] [Accepted: 08/25/2016] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND In-stent neoatherosclerosis is characterized by the delayed appearance of markers of atheroma in the subintima, but the pathophysiology underlying this new disease entity remains unclear. METHODS AND RESULTS We collected 20 human coronary artery stents by removal from explanted hearts. The mean duration of stent implantation was 34 months. In all samples, neoatherosclerosis was detected, particularly in peristrut areas. It consisted of foam cells and cholesterol clefts, with or without calcification, associated with neovascularization. Iron and glycophorin-A were present in peristrut areas, as well as autofluorescent ceroids. Moreover, in response to neoatherosclerosis, tertiary lymphoid organs (tissue lymphoid clusters) often developed in the adventitia. Some of these features could be reproduced in an experimental carotid stenting model in rabbits fed a high-cholesterol diet. Foam cells were present in all samples, and peristrut red blood cells (RBCs) were also detected, as shown by iron deposits and Bandeiraea simplicifiola isolectin-B4 staining of RBC membranes. Finally, in silico models were used to evaluate the compliance mismatch between the rigid struts and the distensible arterial wall using finite element analysis. They show that stenting approximately doubles the local von Mises stress in the intimal layer. CONCLUSIONS We show here that stent implantation both in human and in rabbit arteries is characterized by local peristrut microhemorrhages and finally by both cholesterol accumulation and oxidation, triggering together in-stent neoatherosclerosis. Our data indicate that these processes are likely initiated by an increased mechanical stress due to the compliance mismatch between the rigid stent and the soft wall.
Collapse
Affiliation(s)
- Zaven Terzian
- INSERM U1148, Université Paris-Diderot, Sorbonne Paris-Cité, DHU-FIRE, Hôpital Bichat, Paris, France; Departments of Cardiology, Nuclear Medicine, and Cardiac Surgery, Assistance Publique-Hôpitaux de Paris, DHU-FIRE, RHU iVASC, Hôpital Bichat, Paris, France
| | - T Christian Gasser
- Department of Solid Mechanics, School of Engineering Sciences, KTH Royal Institute of Technology, 100 44, Stockholm, Sweden
| | - Francis Blackwell
- INSERM U1148, Université Paris-Diderot, Sorbonne Paris-Cité, DHU-FIRE, Hôpital Bichat, Paris, France; Departments of Cardiology, Nuclear Medicine, and Cardiac Surgery, Assistance Publique-Hôpitaux de Paris, DHU-FIRE, RHU iVASC, Hôpital Bichat, Paris, France
| | - Fabien Hyafil
- INSERM U1148, Université Paris-Diderot, Sorbonne Paris-Cité, DHU-FIRE, Hôpital Bichat, Paris, France; Departments of Cardiology, Nuclear Medicine, and Cardiac Surgery, Assistance Publique-Hôpitaux de Paris, DHU-FIRE, RHU iVASC, Hôpital Bichat, Paris, France
| | - Liliane Louedec
- INSERM U1148, Université Paris-Diderot, Sorbonne Paris-Cité, DHU-FIRE, Hôpital Bichat, Paris, France
| | - Catherine Deschildre
- INSERM U1148, Université Paris-Diderot, Sorbonne Paris-Cité, DHU-FIRE, Hôpital Bichat, Paris, France
| | - Walid Ghodbane
- Departments of Cardiology, Nuclear Medicine, and Cardiac Surgery, Assistance Publique-Hôpitaux de Paris, DHU-FIRE, RHU iVASC, Hôpital Bichat, Paris, France
| | - Richard Dorent
- INSERM U1148, Université Paris-Diderot, Sorbonne Paris-Cité, DHU-FIRE, Hôpital Bichat, Paris, France; Departments of Cardiology, Nuclear Medicine, and Cardiac Surgery, Assistance Publique-Hôpitaux de Paris, DHU-FIRE, RHU iVASC, Hôpital Bichat, Paris, France
| | - Antonino Nicoletti
- INSERM U1148, Université Paris-Diderot, Sorbonne Paris-Cité, DHU-FIRE, Hôpital Bichat, Paris, France
| | - Marion Morvan
- INSERM U1148, Université Paris-Diderot, Sorbonne Paris-Cité, DHU-FIRE, Hôpital Bichat, Paris, France
| | - Mohammed Nejjari
- INSERM U1148, Université Paris-Diderot, Sorbonne Paris-Cité, DHU-FIRE, Hôpital Bichat, Paris, France; Interventional Cardiology, Centre Cardiologique du Nord, Saint-Denis, France
| | - Laurent Feldman
- INSERM U1148, Université Paris-Diderot, Sorbonne Paris-Cité, DHU-FIRE, Hôpital Bichat, Paris, France; Departments of Cardiology, Nuclear Medicine, and Cardiac Surgery, Assistance Publique-Hôpitaux de Paris, DHU-FIRE, RHU iVASC, Hôpital Bichat, Paris, France
| | - Graciela Pavon-Djavid
- INSERM U1148, Université Paris-Diderot, Sorbonne Paris-Cité, DHU-FIRE, Hôpital Bichat, Paris, France; Paris13-Nord University-Villetaneuse, Villetaneuse, France
| | - Jean-Baptiste Michel
- INSERM U1148, Université Paris-Diderot, Sorbonne Paris-Cité, DHU-FIRE, Hôpital Bichat, Paris, France.
| |
Collapse
|
104
|
Rogers JT, Venkataramani V, Washburn C, Liu Y, Tummala V, Jiang H, Smith A, Cahill CM. A role for amyloid precursor protein translation to restore iron homeostasis and ameliorate lead (Pb) neurotoxicity. J Neurochem 2016; 138:479-94. [PMID: 27206843 DOI: 10.1111/jnc.13671] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2015] [Revised: 03/31/2016] [Accepted: 04/08/2016] [Indexed: 12/30/2022]
Abstract
Iron supplementation ameliorates the neurotoxicity of the environmental contaminant lead (Pb); however, the mechanism remains undefined. Iron is an essential nutrient but high levels are toxic due to the catalytic generation of destructive hydroxyl radicals. Using human neuroblastoma SH-SY5Y cells to model human neurons, we investigated the effect of Pb on proteins of iron homeostasis: the Alzheimer's amyloid precursor protein (APP), which stabilizes the iron exporter ferroportin 1; and, the heavy subunit of the iron-storage protein, ferritin (FTH). Lead (Pb(II) and Pb(IV) inhibited APP translation and raised cytosolic iron(II). Lead also increased iron regulatory protein-1 binding to the cognate 5'untranslated region-specific iron-responsive element (IRE) of APP and FTH mRNAs. Concurrent iron treatment rescued cells from Pb toxicity by specifically restoring APP synthesis, i.e. levels of the APP-related protein, APLP-2, were unchanged. Significantly, iron/IRE-independent over-expression of APP695 protected SH-SY5Y cells from Pb toxicity, demonstrating that APP plays a key role in maintaining safe levels of intracellular iron. Overall, our data support a model of neurotoxicity where Pb enhances iron regulatory protein/IRE-mediated repression of APP and FTH translation. We propose novel treatment options for Pb poisoning to include chelators and the use of small molecules to maintain APP and FTH translation. We propose the following cascade for Lead (Pb) toxicity to neurons; by targeting the interaction between Iron regulatory protein-1 and Iron-responsive elements, Pb caused translational repression of proteins that control intracellular iron homeostasis, including the Alzheimer's amyloid precursor protein (APP) that stabilizes the iron exporter ferroportin, and the ferroxidase heavy subunit of the iron-storage protein, ferritin. When unregulated, IRE-independent over-expression of APP695 protected SH-SY5Y neurons from Pb toxicity. There is a novel and key role for APP in maintaining safe levels of intracellular iron pertinent to lead toxicity.
Collapse
Affiliation(s)
- Jack T Rogers
- Neurochemistry Laboratory, Department of Psychiatry-Neuroscience, Massachusetts General Hospital (East), Harvard Medical School, Charlestown, Massachusetts, USA
| | - Vivek Venkataramani
- Department of Hematology and Medical Oncology, University Medical Center, Goettingen, Germany
| | - Cecilia Washburn
- Neurochemistry Laboratory, Department of Psychiatry-Neuroscience, Massachusetts General Hospital (East), Harvard Medical School, Charlestown, Massachusetts, USA
| | - Yanyan Liu
- Neurochemistry Laboratory, Department of Psychiatry-Neuroscience, Massachusetts General Hospital (East), Harvard Medical School, Charlestown, Massachusetts, USA
| | - Vinusha Tummala
- Neurochemistry Laboratory, Department of Psychiatry-Neuroscience, Massachusetts General Hospital (East), Harvard Medical School, Charlestown, Massachusetts, USA
| | - Hong Jiang
- State Key Disciplines: Physiology, Medical College of Qingdao University, Qingdao, China
| | - Ann Smith
- School of Biological Sciences, University of Missouri-K.C., Kansas City, Missouri, USA
| | - Catherine M Cahill
- Neurochemistry Laboratory, Department of Psychiatry-Neuroscience, Massachusetts General Hospital (East), Harvard Medical School, Charlestown, Massachusetts, USA
| |
Collapse
|
105
|
Alisson-Silva F, Kawanishi K, Varki A. Human risk of diseases associated with red meat intake: Analysis of current theories and proposed role for metabolic incorporation of a non-human sialic acid. Mol Aspects Med 2016; 51:16-30. [PMID: 27421909 DOI: 10.1016/j.mam.2016.07.002] [Citation(s) in RCA: 105] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2016] [Revised: 07/06/2016] [Accepted: 07/07/2016] [Indexed: 02/08/2023]
Abstract
One of the most consistent epidemiological associations between diet and human disease risk is the impact of red meat consumption (beef, pork, and lamb, particularly in processed forms). While risk estimates vary, associations are reported with all-cause mortality, colorectal and other carcinomas, atherosclerotic cardiovascular disease, type II diabetes, and possibly other inflammatory processes. There are many proposed explanations for these associations, some long discussed in the literature. Attempts to explain the effects of red meat consumption have invoked various red meat-associated agents, including saturated fat, high salt intake, Trimethylamine-N-oxide (TMAO) generation by microbiota, and environmental pollutants contaminating red meat, none of which are specific for red meat. Even the frequently mentioned polycyclic aromatic carcinogens arising from high temperature cooking methods are not red meat specific, as these are also generated by grilling poultry or fish, as well as by other forms of cooking. The traditional explanations that appear to be more red meat specific invoke the impact of N-nitroso compounds, heme iron, and the potential of heme to catalyze endogenous nitrosation. However, heme can be denatured by cooking, high levels of plasma hemopexin will block its tissue delivery, and much higher amounts of heme likely originate from red blood cell breakdown in vivo. Therefore, red meat-derived heme could only contribute to colorectal carcinoma risk, via direct local effects. Also, none of these mechanisms explain the apparent human propensity i.e., other carnivores have not been reported at high risk for all these diseases. A more recently proposed hypothesis involves infectious agents in beef from specific dairy cattle as agents of colorectal cancer. We have also described another mechanistic explanation for the human propensity for risk of red-meat associated diseases that is consistent with most observations: metabolic incorporation of a non-human sialic acid N-glycolylneuraminic acid (Neu5Gc) into the tissues of red meat consumers and the subsequent interaction with inflammation-provoking antibodies against this "xenoautoantigen". Overall, we conclude that while multiple mechanisms are likely operative, many proposed theories to date are not specific for red meat, and that the viral and xenoautoantigen theories deserve further consideration. Importantly, there are potential non-toxic dietary antidotes, if the xenoautoantigen theory is indeed correct.
Collapse
Affiliation(s)
- Frederico Alisson-Silva
- Glycobiology Research and Training Center (GRTC), Center for Academic Research and Training in Anthropogeny (CARTA), Departments of Medicine and Cellular & Molecular Medicine, UC San Diego, La Jolla, CA 92093-0687, USA
| | - Kunio Kawanishi
- Glycobiology Research and Training Center (GRTC), Center for Academic Research and Training in Anthropogeny (CARTA), Departments of Medicine and Cellular & Molecular Medicine, UC San Diego, La Jolla, CA 92093-0687, USA
| | - Ajit Varki
- Glycobiology Research and Training Center (GRTC), Center for Academic Research and Training in Anthropogeny (CARTA), Departments of Medicine and Cellular & Molecular Medicine, UC San Diego, La Jolla, CA 92093-0687, USA.
| |
Collapse
|
106
|
Chenglong Z, Jing L, Xia K, Yang T. Association of hemoglobin with ankle-brachial index in general population. Clinics (Sao Paulo) 2016; 71:375-80. [PMID: 27464293 PMCID: PMC4946533 DOI: 10.6061/clinics/2016(07)04] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Accepted: 04/13/2016] [Indexed: 11/18/2022] Open
Abstract
OBJECTIVES Previous studies have demonstrated that both low and high hemoglobin concentrations are predictive of adverse cardiovascular outcomes in various populations. However, an association of hemoglobin with the ankle-brachial index, which is widely used as a screening test for peripheral arterial disease, has not yet been identified. METHODS We examined 786 subjects (236 women and 550 men) who received routine physical check-ups. The ankle-brachial index and several hematological parameters, including the hemoglobin level, hematocrit and red blood cell count and other demographic and biochemical characteristics were collected. Univariate and multivariate linear regression analyses were performed to assess the relationships between the ankle-brachial index and the independent determinants. Receiver operating characteristic curve analysis was conducted to calculate the cut-off level of hemoglobin for detecting a relatively low ankle-brachial index (less than 20% of all subjects, which was 1.02). RESULTS The hemoglobin level, hematocrit and red blood cell count were correlated with the ankle-brachial index in the males (r=-0.274, r=-0.224 and r=-0.273, respectively, p<0.001 for all), but these associations were not significant in the females. Multivariate linear regression analysis revealed that the independent determinants of the ankle-brachial index included age, total cholesterol, high-density lipoprotein cholesterol and the white blood cell count for the females and age, hypertension, total cholesterol and hemoglobin (β=-0.001, p<0.001) for the males after adjusting for confounding factors. Receiver operating characteristic curve analysis revealed that the cut-off level of hemoglobin for predicting a low ankle-brachial index was 156.5 g/L in the males. CONCLUSIONS A high hemoglobin concentration was independently correlated with a low ankle-brachial index in the healthy males, indicating that an elevation in this level may be associated with an increased atherosclerosis risk.
Collapse
Affiliation(s)
- Zhang Chenglong
- Central South University, Xiangya Hospital, Department of Cardiology, Changsha, Hunan/China
| | - Lei Jing
- Central South University, Xiangya Hospital, Department of Cardiology, Changsha, Hunan/China
| | - Ke Xia
- Central South University, Xiangya Hospital, Department of Cardiology, Changsha, Hunan/China
| | - Tianlun Yang
- Central South University, Xiangya Hospital, Department of Cardiology, Changsha, Hunan/China
- E-mail:
| |
Collapse
|
107
|
Bou Khalil R, Khoury E, Koussa S. Linking multiple pathogenic pathways in Alzheimer’s disease. World J Psychiatry 2016; 6:208-214. [PMID: 27354962 PMCID: PMC4919259 DOI: 10.5498/wjp.v6.i2.208] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Revised: 04/16/2016] [Accepted: 05/11/2016] [Indexed: 02/05/2023] Open
Abstract
Alzheimer’s disease (AD) is a chronic neurodegenerative disorder presenting as progressive cognitive decline with dementia that does not, to this day, benefit from any disease-modifying drug. Multiple etiologic pathways have been explored and demonstrate promising solutions. For example, iron ion chelators, such as deferoxamine, are a potential therapeutic solution around which future studies are being directed. Another promising domain is related to thrombin inhibitors. In this minireview, a common pathophysiological pathway is suggested for the pathogenesis of AD to prove that all these mechanisms converge onto the same cascade of neuroinflammatory events. This common pathway is initiated by the presence of vascular risk factors that induce brain tissue hypoxia, which leads to endothelial cell activation. However, the ensuing hypoxia stimulates the production and release of reactive oxygen species and pro-inflammatory proteins. Furthermore, the endothelial activation may become excessive and dysfunctional in predisposed individuals, leading to thrombin activation and iron ion decompartmentalization. The oxidative stress that results from these modifications in the neurovascular unit will eventually lead to neuronal and glial cell death, ultimately leading to the development of AD. Hence, future research in this field should focus on conducting trials with combinations of potentially efficient treatments, such as the combination of intranasal deferoxamine and direct thrombin inhibitors.
Collapse
|
108
|
Pisano G, Lombardi R, Fracanzani AL. Vascular Damage in Patients with Nonalcoholic Fatty Liver Disease: Possible Role of Iron and Ferritin. Int J Mol Sci 2016; 17:ijms17050675. [PMID: 27164079 PMCID: PMC4881501 DOI: 10.3390/ijms17050675] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2016] [Revised: 04/20/2016] [Accepted: 04/26/2016] [Indexed: 02/06/2023] Open
Abstract
Non Alcoholic Fatty Liver Disease (NAFLD) is the most common chronic liver disease in Western countries. Recent data indicated that NAFLD is a risk factor by itself contributing to the development of cardiovascular disease independently of classical known risk factors. Hyperferritinemia and mild increased iron stores are frequently observed in patients with NAFLD and several mechanisms have been proposed to explain the role of iron, through oxidative stress and interaction with insulin metabolism, in the development of vascular damage. Moreover, iron depletion has been shown to decrease atherogenesis in experimental models and in humans. This review presents the recent evidence on epidemiology, pathogenesis, and the possible explanation of the role of iron and ferritin in the development of cardiovascular damage in patients with NAFLD, and discusses the possible interplay between metabolic disorders associated with NAFLD and iron in the development of cardiovascular disease.
Collapse
Affiliation(s)
- Giuseppina Pisano
- Department of Pathophysiology and Transplantation, Ca' Granda IRCCS Foundation, Policlinico Hospital, University of Milan, Centre of the Study of Metabolic and Liver Diseases, Via Francesco Sforza 35, 20122 Milan, Italy.
| | - Rosa Lombardi
- Department of Pathophysiology and Transplantation, Ca' Granda IRCCS Foundation, Policlinico Hospital, University of Milan, Centre of the Study of Metabolic and Liver Diseases, Via Francesco Sforza 35, 20122 Milan, Italy.
| | - Anna Ludovica Fracanzani
- Department of Pathophysiology and Transplantation, Ca' Granda IRCCS Foundation, Policlinico Hospital, University of Milan, Centre of the Study of Metabolic and Liver Diseases, Via Francesco Sforza 35, 20122 Milan, Italy.
| |
Collapse
|
109
|
Abstract
OBJECTIVES The aim of this review was to highlight recent advances in our understanding of the pathogenesis of malignant transformation of endometriosis. METHODS This study reviewed the English-language literature concerning basic science studies of the potential promotion of carcinogenesis. RESULTS Repeated episodes of hemorrhage occur in endometriosis at the onset of menstruation. Extracellular hemoglobin, heme, and iron derivatives in endometriosis cause DNA damage and mutations, which create increased cellular susceptibility to oxidant-mediated cell killing. Excess DNA damage and mutations are linked to cell death, but not carcinogenesis. In response to an oxidative and inflammatory microenvironment, endometriotic cells and macrophages secrete antioxidants that control excess oxidative stress in the surrounding environment. Exposure of endometriotic cells to a sublethal level of oxidative stress may lead to carcinogenesis. Macrophages also secrete immunosuppressive factors that lead to promotion of malignant transformation. DISCUSSION At least two potential scenarios could result in ovarian cancer arising from endometriosis. The first step: extracellular hemoglobin, heme, and iron cause cellular oxidative damage by promoting reactive oxygen species formation, which results in DNA damage and mutations (ovarian cancer initiation from endometriosis). The second step: cancer progression may be associated with persistent antioxidant production favoring a protumoral microenvironment.
Collapse
Affiliation(s)
- Hiroshi Kobayashi
- a Department of Obstetrics and Gynecology , Nara Medical University , Japan
| |
Collapse
|
110
|
Sun J, Canton G, Balu N, Hippe DS, Xu D, Liu J, Hatsukami TS, Yuan C. Blood Pressure Is a Major Modifiable Risk Factor Implicated in Pathogenesis of Intraplaque Hemorrhage: An In Vivo Magnetic Resonance Imaging Study. Arterioscler Thromb Vasc Biol 2016; 36:743-9. [PMID: 26848155 DOI: 10.1161/atvbaha.115.307043] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Accepted: 01/20/2016] [Indexed: 12/19/2022]
Abstract
OBJECTIVE Effective prevention and management strategies of intraplaque hemorrhage (IPH) remain elusive because of our limited knowledge regarding its contributing factors. This hypothesis-generating study aimed to investigate associations between cardiovascular risk factors and IPH for improved understanding of the pathogenesis of IPH. APPROACH AND RESULTS Asymptomatic subjects with 16% to 79% stenosis on ultrasound underwent carotid magnetic resonance imaging using a large-coverage, 3-dimensional magnetic resonance imaging protocol. Individual plaques (maximum thickness >1.5 mm) in bilateral carotid arteries were identified, and presence of IPH was determined. From 80 subjects, 176 de novo plaques were measured, of which 38 (21.6%) contained IPH. Blood pressure (BP), primarily low diastolic BP, was associated with IPH in multivariate analysis adjusted for age, sex, and plaque size (odds ratio with 95% confidence interval per 10-mm Hg increase: 0.51 [0.30-0.88]), which was little changed after adjusting for antihypertensive use and systemic atherosclerosis. Antiplatelet use was associated with IPH in age and sex-adjusted models (P=0.018), for which a trend remained after considering plaque size and past medical history (odds ratio for aspirin alone versus none: 3.1 [0.66-14.8]; odds ratio for clopidogrel or dual therapy versus none: 5.3 [0.80-35.0]; P=0.083). CONCLUSIONS Low diastolic BP was independently associated with IPH, which was not attributed to treatment difference or BP changes from systemic atherosclerosis. Hemodynamic changes from lowering diastolic BP may be the pathophysiological link. Prospective serial studies are needed to assess whether BP and antiplatelet use are associated with the development of new or repeated IPH.
Collapse
Affiliation(s)
- Jie Sun
- From the Departments of Radiology (J.S., N.B., D.S.H., D.X., C.Y.), Mechanical Engineering (G.C.), Bioengineering (J.L., C.Y.), and Surgery (T.S.H.), University of Washington, Seattle
| | - Gador Canton
- From the Departments of Radiology (J.S., N.B., D.S.H., D.X., C.Y.), Mechanical Engineering (G.C.), Bioengineering (J.L., C.Y.), and Surgery (T.S.H.), University of Washington, Seattle
| | - Niranjan Balu
- From the Departments of Radiology (J.S., N.B., D.S.H., D.X., C.Y.), Mechanical Engineering (G.C.), Bioengineering (J.L., C.Y.), and Surgery (T.S.H.), University of Washington, Seattle
| | - Daniel S Hippe
- From the Departments of Radiology (J.S., N.B., D.S.H., D.X., C.Y.), Mechanical Engineering (G.C.), Bioengineering (J.L., C.Y.), and Surgery (T.S.H.), University of Washington, Seattle
| | - Dongxiang Xu
- From the Departments of Radiology (J.S., N.B., D.S.H., D.X., C.Y.), Mechanical Engineering (G.C.), Bioengineering (J.L., C.Y.), and Surgery (T.S.H.), University of Washington, Seattle
| | - Jin Liu
- From the Departments of Radiology (J.S., N.B., D.S.H., D.X., C.Y.), Mechanical Engineering (G.C.), Bioengineering (J.L., C.Y.), and Surgery (T.S.H.), University of Washington, Seattle
| | - Thomas S Hatsukami
- From the Departments of Radiology (J.S., N.B., D.S.H., D.X., C.Y.), Mechanical Engineering (G.C.), Bioengineering (J.L., C.Y.), and Surgery (T.S.H.), University of Washington, Seattle
| | - Chun Yuan
- From the Departments of Radiology (J.S., N.B., D.S.H., D.X., C.Y.), Mechanical Engineering (G.C.), Bioengineering (J.L., C.Y.), and Surgery (T.S.H.), University of Washington, Seattle.
| |
Collapse
|
111
|
|
112
|
Shimizu Y, Kadota K, Nakazato M, Noguchi Y, Koyamatsu J, Yamanashi H, Nagayoshi M, Nagata S, Arima K, Maeda T. Hemoglobin as a possible biochemical index of hypertension-induced vascular damage. J Physiol Anthropol 2016; 35:4. [PMID: 26818627 PMCID: PMC4730762 DOI: 10.1186/s40101-016-0085-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2015] [Accepted: 01/15/2016] [Indexed: 02/06/2023] Open
Abstract
Background We previously reported on the positive association of hemoglobin with hypertension and atherosclerosis. On the other hand, hepatocyte growth factor (HGF) has been evaluated as a possible biochemical index of hypertension-induced vascular damage. However, no studies have reported on a correlation between hemoglobin and HGF accounting for hypertension status. Methods A cross-sectional study of 1108 subjects (392 men and 716 women, 40–93 years old) who were undergoing a general checkup in 2014 was conducted. Results Multiple linear regression analysis adjustment for known cardiovascular risk factors showed no significant correlation between hemoglobin and HGF in non-hypertensive subjects, but a significant positive correlation in hypertensive subjects; β (parameter estimate) = 0.3 (p = 0.975) for non-hypertensive men, β = 0.4 (p = 0.925) for non-hypertensive women, β = 32.7 (p < 0.001) for hypertensive men, and β = 18.7 (p = 0.002) for hypertensive women. Conclusion We found a significant positive correlation between hemoglobin and HGF among hypertensive men and women. Like HGF, hemoglobin may be a useful indicator to evaluate hypertension-induced vascular damage. Since hemoglobin can easily be measured, these results support hemoglobin as an efficient tool to evaluate vascular damage induced by hypertension in daily medical practice.
Collapse
Affiliation(s)
- Yuji Shimizu
- Nagasaki University Graduate School of Biomedical Science, Nagasaki, Japan.
| | - Koichiro Kadota
- Nagasaki University Graduate School of Biomedical Science, Nagasaki, Japan
| | - Mio Nakazato
- Nagasaki University Graduate School of Biomedical Science, Nagasaki, Japan
| | - Yuko Noguchi
- Nagasaki University Graduate School of Biomedical Science, Nagasaki, Japan
| | - Jun Koyamatsu
- Nagasaki University Graduate School of Biomedical Science, Nagasaki, Japan
| | - Hirotomo Yamanashi
- Nagasaki University Graduate School of Biomedical Science, Nagasaki, Japan
| | - Mako Nagayoshi
- Nagasaki University Graduate School of Biomedical Science, Nagasaki, Japan
| | - Shuichi Nagata
- Nagasaki University Graduate School of Biomedical Science, Nagasaki, Japan
| | - Kazuhiko Arima
- Nagasaki University Graduate School of Biomedical Science, Nagasaki, Japan
| | - Takahiro Maeda
- Nagasaki University Graduate School of Biomedical Science, Nagasaki, Japan
| |
Collapse
|
113
|
Righy C, Bozza MT, Oliveira MF, Bozza FA. Molecular, Cellular and Clinical Aspects of Intracerebral Hemorrhage: Are the Enemies Within? Curr Neuropharmacol 2016; 14:392-402. [PMID: 26714583 PMCID: PMC4876594 DOI: 10.2174/1570159x14666151230110058] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2015] [Revised: 11/28/2015] [Accepted: 12/29/2015] [Indexed: 12/13/2022] Open
Abstract
Hemorrhagic stroke is a disease with high incidence and mortality rates. In addition to the mass lesions that result from hemorrhagic stroke, substances such as the blood-derived products (BDP) (hemoglobin (Hb), heme and iron) induce a potent inflammatory response and exert direct toxic effects on neurons, astrocytes, and microglia. In the present review, we discuss the mechanisms of brain injury secondary to hemorrhagic stroke, focusing on the involvement of BDP as major players of cellular redox imbalance, inflammation, and glutamate excitotoxicity. Potential natural mechanisms of protection against free Hb and heme such as haptoglobin and hemopexin, respectively, are highlighted. We finally discuss the experimental and clinical trials targeting free iron and heme scavenging as well as inflammation, as potential new therapies to minimize the devastating effects of hemorrhagic stroke on brain structure and function.
Collapse
Affiliation(s)
- Cássia Righy
- Avenida Brasil 4.365, Manguinhos, Rio de Janeiro-RJ, CEP 21.040-900, Pavilhão Gaspar Viana.
| | | | | | | |
Collapse
|
114
|
Deuel JW, Vallelian F, Schaer CA, Puglia M, Buehler PW, Schaer DJ. Different target specificities of haptoglobin and hemopexin define a sequential protection system against vascular hemoglobin toxicity. Free Radic Biol Med 2015; 89:931-43. [PMID: 26475040 DOI: 10.1016/j.freeradbiomed.2015.09.016] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/22/2015] [Revised: 07/31/2015] [Accepted: 09/20/2015] [Indexed: 11/19/2022]
Abstract
Free hemoglobin (Hb) triggered vascular damage occurs in many hemolytic diseases, such as sickle cell disease, with an unmet need for specific therapeutic interventions. Based on clinical observations the Hb and heme scavenger proteins haptoglobin (Hp) and hemopexin (Hx) have been characterized as a sequential defense system with Hp as the primary protector and Hx as a backup when all Hp is depleted during more severe intravascular hemolysis. In this study we present a mechanistic rationale for this paradigm based on a combined biochemical and cell biological approach directed at understanding the unique roles of Hp and Hx in Hb detoxification. Using a novel in vitro model of Hb triggered endothelial damage, which recapitulates the well-characterized pathophysiologic sequence of oxyHb(Fe(2+)) transformation to ferric Hb(Fe(3+)), free heme transfer from ferric Hb(Fe(3+)) to lipoprotein and subsequent oxidative reactions in the lipophilic phase. The accumulation of toxic lipid peroxidation products liberated during oxidation reactions ultimately lead to endothelial damage characterized by a specific gene expression pattern with reduced cellular ATP and monolayer disintegration. Quantitative analysis of key chemical and biological parameters allowed us to precisely define the mechanisms and concentrations required for Hp and Hx to prevent this toxicity. In the case of Hp we defined an exponential relationship between Hp availability relative to oxyHb(Fe(2+)) and related protective activity. This exponential relationship demonstrates that large Hp quantities are required to prevent Hb toxicity. In contrast, the linear relationship between Hx concentration and protection defines a highly efficient backup scavenger system during conditions of large excess of free oxyHb(Fe(2+)) that occurs when all Hp is consumed. The diverse protective function of Hp and Hx in this model can be explained by the different target specificities of the two proteins.
Collapse
Affiliation(s)
- Jeremy W Deuel
- Division of Internal Medicine, University Hospital of Zurich, Switzerland
| | - Florence Vallelian
- Division of Internal Medicine, University Hospital of Zurich, Switzerland
| | - Christian A Schaer
- Division of Internal Medicine, University Hospital of Zurich, Switzerland
| | - Michele Puglia
- Division of Internal Medicine, University Hospital of Zurich, Switzerland; Functional Genomics Center, University of Zurich, Switzerland
| | - Paul W Buehler
- Center of Biologics Evaluation and Research (CBER), FDA, Silver Spring, Maryland, USA
| | - Dominik J Schaer
- Division of Internal Medicine, University Hospital of Zurich, Switzerland.
| |
Collapse
|
115
|
Marques VB, Nascimento TB, Ribeiro RF, Broseghini-Filho GB, Rossi EM, Graceli JB, dos Santos L. Chronic iron overload in rats increases vascular reactivity by increasing oxidative stress and reducing nitric oxide bioavailability. Life Sci 2015; 143:89-97. [PMID: 26523985 DOI: 10.1016/j.lfs.2015.10.034] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2015] [Revised: 10/13/2015] [Accepted: 10/28/2015] [Indexed: 02/07/2023]
Abstract
AIMS Iron overload in animal models and humans increases oxidative stress and induces cardiomyopathy. It has been suggested that the vasculature is also damaged, but the impacts on vascular reactivity and the underlying mechanisms remain poorly understood. In this study, we aimed to identify possible changes in the vascular reactivity of aortas from iron overloaded rats and investigate the underlying mechanisms. MAIN METHODS Rats were treated with 100mg/kg/day iron-dextran, ip, five days a week for four weeks and compared to a saline-injected group. KEY FINDINGS Chronic iron administration increased serum iron and transferrin saturation with significant deposition in the liver. Additionally, iron overload significantly increased the vasoconstrictor response in aortic rings as assessed in vitro, with reduced influence of endothelial denudation or l-NAME incubation on the vascular reactivity. In vitro assay with DAF-2 indicated reduced NO production in the iron overload group. Iron overload-induced vascular hyperactivity was reversed by incubation with tiron, catalase, apocynin, allopurinol and losartan. Moreover, malondialdehyde was elevated in the plasma, and O2(•-) generation and NADPH oxidase subunit (p22phox) expression were increased in the aortas of iron-loaded rats. SIGNIFICANCE Our results demonstrated that chronic iron overload is associated with altered vascular reactivity and the loss of endothelial modulation of the vascular tone. This iron loading-induced endothelial dysfunction and reduced nitric oxide bioavailability may be a result of increased production of reactive oxygen species and local renin-angiotensin system activation.
Collapse
Affiliation(s)
| | | | | | | | - Emilly Martinelly Rossi
- Department of Physiological Sciences, Federal University of Espirito Santo, Vitoria, ES, Brazil
| | | | - Leonardo dos Santos
- Department of Physiological Sciences, Federal University of Espirito Santo, Vitoria, ES, Brazil.
| |
Collapse
|
116
|
Lanceta L, Mattingly JM, Li C, Eaton JW. How Heme Oxygenase-1 Prevents Heme-Induced Cell Death. PLoS One 2015; 10:e0134144. [PMID: 26270345 PMCID: PMC4535878 DOI: 10.1371/journal.pone.0134144] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2015] [Accepted: 07/06/2015] [Indexed: 01/22/2023] Open
Abstract
Earlier observations indicate that free heme is selectively toxic to cells lacking heme oxygenase-1 (HO-1) but how this enzyme prevents heme toxicity remains unexplained. Here, using A549 (human lung cancer) and immortalized human bronchial epithelial cells incubated with exogenous heme, we find knock-down of HO-1 using siRNA does promote the accumulation of cell-associated heme and heme-induced cell death. However, it appears that the toxic effects of heme are exerted by “loose” (probably intralysosomal) iron because cytotoxic effects of heme are lessened by pre-incubation of HO-1 deficient cells with desferrioxamine (which localizes preferentially in the lysosomal compartment). Desferrioxamine also decreases lysosomal rupture promoted by intracellularly generated hydrogen peroxide. Supporting the importance of endogenous oxidant production, both chemical and siRNA inhibition of catalase activity predisposes HO-1 deficient cells to heme-mediated killing. Importantly, it appears that HO-1 deficiency somehow blocks the induction of ferritin; control cells exposed to heme show ~10-fold increases in ferritin heavy chain expression whereas in heme-exposed HO-1 deficient cells ferritin expression is unchanged. Finally, overexpression of ferritin H chain in HO-1 deficient cells completely prevents heme-induced cytotoxicity. Although two other products of HO-1 activity–CO and bilirubin–have been invoked to explain HO-1-mediated cytoprotection, we conclude that, at least in this experimental system, HO-1 activity triggers the induction of ferritin and the latter is actually responsible for the cytoprotective effects of HO-1 activity.
Collapse
Affiliation(s)
- Lilibeth Lanceta
- Molecular Targets Program, James Graham Brown Cancer Center, University of Louisville, Louisville, Kentucky, United States of America
| | - Jacob M. Mattingly
- Molecular Targets Program, James Graham Brown Cancer Center, University of Louisville, Louisville, Kentucky, United States of America
| | - Chi Li
- Molecular Targets Program, James Graham Brown Cancer Center, University of Louisville, Louisville, Kentucky, United States of America
- * E-mail: (CL); (JWE)
| | - John W. Eaton
- Molecular Targets Program, James Graham Brown Cancer Center, University of Louisville, Louisville, Kentucky, United States of America
- * E-mail: (CL); (JWE)
| |
Collapse
|
117
|
Voskou S, Aslan M, Fanis P, Phylactides M, Kleanthous M. Oxidative stress in β-thalassaemia and sickle cell disease. Redox Biol 2015; 6:226-239. [PMID: 26285072 PMCID: PMC4543215 DOI: 10.1016/j.redox.2015.07.018] [Citation(s) in RCA: 111] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2015] [Revised: 07/30/2015] [Accepted: 07/31/2015] [Indexed: 12/21/2022] Open
Abstract
Sickle cell disease and β-thalassaemia are inherited haemoglobinopathies resulting in structural and quantitative changes in the β-globin chain. These changes lead to instability of the generated haemoglobin or to globin chain imbalance, which in turn impact the oxidative environment both intracellularly and extracellularly. The ensuing oxidative stress and the inability of the body to adequately overcome it are, to a large extent, responsible for the pathophysiology of these diseases. This article provides an overview of the main players and control mechanisms involved in the establishment of oxidative stress in these haemoglobinopathies.
Collapse
Affiliation(s)
- S Voskou
- The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus
| | - M Aslan
- Akdeniz University, Faculty of Medicine, Department of Medical Biochemistry, Antalya, Turkey
| | - P Fanis
- The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus
| | - M Phylactides
- The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus.
| | - M Kleanthous
- The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus
| |
Collapse
|
118
|
Smith A, McCulloh RJ. Hemopexin and haptoglobin: allies against heme toxicity from hemoglobin not contenders. Front Physiol 2015; 6:187. [PMID: 26175690 PMCID: PMC4485156 DOI: 10.3389/fphys.2015.00187] [Citation(s) in RCA: 175] [Impact Index Per Article: 19.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2015] [Accepted: 06/11/2015] [Indexed: 01/29/2023] Open
Abstract
The goal here is to describe our current understanding of heme metabolism and the deleterious effects of "free" heme on immunological processes, endothelial function, systemic inflammation, and various end-organ tissues (e.g., kidney, lung, liver, etc.), with particular attention paid to the role of hemopexin (HPX). Because heme toxicity is the impetus for much of the pathology in sepsis, sickle cell disease (SCD), and other hemolytic conditions, the biological importance and clinical relevance of HPX, the predominant heme binding protein, is reinforced. A perspective on the function of HPX and haptoglobin (Hp) is presented, updating how these two proteins and their respective receptors act simultaneously to protect the body in clinical conditions that entail hemolysis and/or systemic intravascular (IVH) inflammation. Evidence from longitudinal studies in patients supports that HPX plays a Hp-independent role in genetic and non-genetic hemolytic diseases without the need for global Hp depletion. Evidence also supports that HPX has an important role in the prognosis of complex illnesses characterized predominantly by the presence of hemolysis, such as SCD, sepsis, hemolytic-uremic syndrome, and conditions involving IVH and extravascular hemolysis (EVH), such as that generated by extracorporeal circulation during cardiopulmonary bypass (CPB) and from blood transfusions. We propose that quantitating the amounts of plasma heme, HPX, Hb-Hp, heme-HPX, and heme-albumin levels in various disease states may aid in the diagnosis and treatment of the above-mentioned conditions, which is crucial to developing targeted plasma protein supplementation (i.e., "replenishment") therapies for patients with heme toxicity due to HPX depletion.
Collapse
Affiliation(s)
- Ann Smith
- School of Biological Sciences, University of Missouri-Kansas CityKansas City, MO, USA
| | - Russell J. McCulloh
- Pediatric and Adult Infectious Diseases, Children's Mercy-Kansas CityKansas City, MO, USA
- School of Medicine, University of Missouri-Kansas CityKansas City, MO, USA
| |
Collapse
|
119
|
Winner MW, Sharkey-Toppen T, Zhang X, Pennell ML, Simonetti OP, Zweier JL, Vaccaro PS, Raman SV. Iron and noncontrast magnetic resonance T2* as a marker of intraplaque iron in human atherosclerosis. J Vasc Surg 2015; 61:1556-64. [PMID: 24674272 PMCID: PMC4175307 DOI: 10.1016/j.jvs.2014.02.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2013] [Revised: 02/04/2014] [Accepted: 02/06/2014] [Indexed: 12/21/2022]
Abstract
OBJECTIVE Iron has been implicated in atherogenesis and plaque destabilization, whereas less is known about iron-related proteins in this disease. We compared ex vivo quantities with in vivo vessel wall T2*, which is a noncontrast magnetic resonance relaxation time that quantitatively shortens with increased tissue iron content. We also tested the hypothesis that patients with carotid atherosclerosis have abnormal T2* times vs controls that would help support a role for iron in human atherosclerosis. METHODS Forty-six patients undergoing carotid endarterectomy and 14 subjects without carotid disease were prospectively enrolled to undergo carotid magnetic resonance imaging. Ex vivo measurements were performed on explanted plaque and 17 mammary artery samples. RESULTS Plaques vs normal arteries had higher levels of ferritin (median, 7.3 [interquartile range (IQR), 4-13.8] vs 1.0 [IQR, 0.6-1.3] ng/mg; P < .001) and oxidized low-density lipoprotein (median, 0.17 [IQR, 0.12-0.30] vs 0.01 [IQR, 0.003-0.03] ng/mg; P < .001) as well as hepcidin (median, 8.7 [IQR, 4.6-12.4] vs 2.6 [IQR, 1.3-7.0] ng/mL; P = .03); serum hepcidin levels did not distinguish atherosclerosis patients from controls (median, 40.6 [IQR, 18.8-88.6] vs 33.9 [IQR, 17.6-55.2]; P = .42). Shorter in vivo T2* paralleled larger plaque volume (ρ = -.44; P = .01), and diseased arteries had shorter T2* values compared with controls (median, 17.7 ± 4.3 vs 23.0 ± 2.4 ms; P < .001). CONCLUSIONS Diseased arteries have greater levels of iron-related proteins ex vivo and shorter T2* times in vivo. Further studies should help define the role of T2* as a biomarker of iron and atherosclerosis.
Collapse
Affiliation(s)
- Marshall W Winner
- The Ohio State University, Davis Heart and Lung Research Institute, Columbus, Ohio
| | | | - Xiaolan Zhang
- The Ohio State University, Davis Heart and Lung Research Institute, Columbus, Ohio
| | - Michael L Pennell
- The Ohio State University, Davis Heart and Lung Research Institute, Columbus, Ohio
| | - Orlando P Simonetti
- The Ohio State University, Davis Heart and Lung Research Institute, Columbus, Ohio
| | - Jay L Zweier
- The Ohio State University, Davis Heart and Lung Research Institute, Columbus, Ohio
| | - Patrick S Vaccaro
- The Ohio State University, Davis Heart and Lung Research Institute, Columbus, Ohio
| | - Subha V Raman
- The Ohio State University, Davis Heart and Lung Research Institute, Columbus, Ohio.
| |
Collapse
|
120
|
Soutyrine A, Yogasingam N, Huang H, Mitchell G. Effects of heme-PrP complex on cell-free conversion and peroxidase-linked immunodetection of prions in blood-based assays. Res Vet Sci 2015; 101:168-74. [PMID: 26022071 DOI: 10.1016/j.rvsc.2015.05.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2014] [Revised: 05/08/2015] [Accepted: 05/13/2015] [Indexed: 01/02/2023]
Abstract
Prion protein (PrP) binding to natural and synthetic porphyrins has been previously demonstrated but the effects of endogenous heme interactions with PrP remain uncertain. This study investigated implications of this interaction in blood-based peroxidase-linked prion immunodetection and seeded conversion of cellular prion (PrP(C)) into disease associated form (PrP(Sc)). Heme binding to recombinant PrP(C) enhanced intrinsic peroxidase activity (POD) by 2.5-fold and POD inherent to denatured blood accounted for over 84% of luminol-based substrate oxidation in a prion immunodetection assay. An immuno-capture assay showed that 75-98% of blood POD was attributable to binding of PrP(C) with endogenous heme. Additionally, 10 μM heme inhibited (P<0.05) the seeded conversion of PrP(C) to PrP(Sc) through the protein misfolding cycling amplification assay. We conclude that the observed effects can interfere with cell-free conversion and peroxidase-linked immunodetection of prions in blood-based assays. These results indicate that heme-PrP interactions could modulate intrinsic POD and protect PrP(C) from conversion into PrP(Sc).
Collapse
Affiliation(s)
- Andrei Soutyrine
- Ottawa Laboratory (Fallowfield), Canadian Food Inspection Agency, Ottawa, Ontario, Canada.
| | - Nishandan Yogasingam
- Ottawa Laboratory (Fallowfield), Canadian Food Inspection Agency, Ottawa, Ontario, Canada
| | - Hongsheng Huang
- Ottawa Laboratory (Fallowfield), Canadian Food Inspection Agency, Ottawa, Ontario, Canada
| | - Gordon Mitchell
- Ottawa Laboratory (Fallowfield), Canadian Food Inspection Agency, Ottawa, Ontario, Canada
| |
Collapse
|
121
|
Xu J, Lu X, Shi GP. Vasa vasorum in atherosclerosis and clinical significance. Int J Mol Sci 2015; 16:11574-608. [PMID: 26006236 PMCID: PMC4463718 DOI: 10.3390/ijms160511574] [Citation(s) in RCA: 89] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2015] [Accepted: 05/11/2015] [Indexed: 12/12/2022] Open
Abstract
Atherosclerosis is a chronic inflammatory disease that leads to several acute cardiovascular complications with poor prognosis. For decades, the role of the adventitial vasa vasorum (VV) in the initiation and progression of atherosclerosis has received broad attention. The presence of VV neovascularization precedes the apparent symptoms of clinical atherosclerosis. VV also mediates inflammatory cell infiltration, intimal thickening, intraplaque hemorrhage, and subsequent atherothrombosis that results in stroke or myocardial infarction. Intraplaque neovessels originating from VV can be immature and hence susceptible to leakage, and are thus regarded as the leading cause of intraplaque hemorrhage. Evidence supports VV as a new surrogate target of atherosclerosis evaluation and treatment. This review provides an overview into the relationship between VV and atherosclerosis, including the anatomy and function of VV, the stimuli of VV neovascularization, and the available underlying mechanisms that lead to poor prognosis. We also summarize translational researches on VV imaging modalities and potential therapies that target VV neovascularization or its stimuli.
Collapse
Affiliation(s)
- Junyan Xu
- Second Clinical Medical College, Zhujiang Hospital and Southern Medical University, Guangzhou 510280, China.
| | - Xiaotong Lu
- Second Clinical Medical College, Zhujiang Hospital and Southern Medical University, Guangzhou 510280, China.
| | - Guo-Ping Shi
- Second Clinical Medical College, Zhujiang Hospital and Southern Medical University, Guangzhou 510280, China.
- Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA.
| |
Collapse
|
122
|
Raman SV, Sharkey-Toppen TP, Tran T, Liu JX, McCarthy B, He X, Smart S, Gulati M, Wexler R, Simonetti OP, Jackson RD. Iron, inflammation and atherosclerosis risk in men vs. perimenopausal women. Atherosclerosis 2015; 241:249-54. [PMID: 25817132 DOI: 10.1016/j.atherosclerosis.2015.03.032] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/21/2015] [Revised: 02/15/2015] [Accepted: 03/16/2015] [Indexed: 01/26/2023]
Abstract
OBJECTIVE Age at first atherosclerotic event is typically older for women vs. men; monthly iron loss has been postulated to contribute to this advantage. We investigated the relationship between an MRI-based arterial wall biomarker and the serum inflammatory biomarker high-sensitivity C-reactive protein (hsCRP) in perimenopausal women vs. men. METHODS AND RESULTS Women without evident atherosclerotic disease were prospectively enrolled and observed over 24 months of menopause transition, indicated by hormone levels and reduction in median number of menstrual cycles from 4 [3-6] per year to 0 [0-1] per year (P < 0.01). Higher hsCRP predicted shorter carotid artery wall T2* in women entering the menopause transition (r = -0.3139, P = 0.0014); this relationship weakened after 24 months of perimenopause in women (r = -0.1718, P = 0.0859) and was not significant in a cohort of men matched for age and cardiovascular risk category (r = -0.0310, P = 0.8362). Serum ferritin increased from baseline to 24-month follow-up during women's menopause transition (37 [20-79] to 67 [36-97] ng/mL, P < 0.01), but still remained lower compared to men (111 [45-220] ng/mL, P < 0.01). Circulating ferritin levels correlated with arterial wall T2* values in women at baseline (r = -0.3163, P = 0.0013) but not in women after 24 months (r = -0.0730, P = 0.4684) of menopause transition nor in men (r = 0.0862, P = 0.5644). CONCLUSIONS An arterial wall iron-based imaging biomarker reflects degree of systemic inflammation in younger women, whereas this relationship is lost as women transition through menopause to become more similar to men. Iron homeostasis and inflammation in the arterial wall microenvironment warrants further investigation as a potential early target for interventions that mitigate atherosclerosis risk.
Collapse
Affiliation(s)
- Subha V Raman
- Ohio State University (OSU), Davis Heart and Lung Research Institute, 473 W. 12th Ave, Suite 200, Columbus, OH 43210, USA.
| | - Travis P Sharkey-Toppen
- Ohio State University (OSU), Davis Heart and Lung Research Institute, 473 W. 12th Ave, Suite 200, Columbus, OH 43210, USA
| | - Tam Tran
- Ohio State University (OSU), Davis Heart and Lung Research Institute, 473 W. 12th Ave, Suite 200, Columbus, OH 43210, USA
| | - Jim X Liu
- Ohio State University (OSU), Davis Heart and Lung Research Institute, 473 W. 12th Ave, Suite 200, Columbus, OH 43210, USA
| | - Beth McCarthy
- Ohio State University (OSU), Davis Heart and Lung Research Institute, 473 W. 12th Ave, Suite 200, Columbus, OH 43210, USA
| | - Xin He
- University of Maryland, Department of Epidemiology and Biostatistics, 2234H SPH Building, College Park, MD 20742, USA
| | - Suzanne Smart
- Ohio State University (OSU), Davis Heart and Lung Research Institute, 473 W. 12th Ave, Suite 200, Columbus, OH 43210, USA
| | - Martha Gulati
- Ohio State University (OSU), Davis Heart and Lung Research Institute, 473 W. 12th Ave, Suite 200, Columbus, OH 43210, USA
| | - Randell Wexler
- OSU, Department of Family Medicine, 2231 N. High St, Columbus, OH 43210, USA
| | - Orlando P Simonetti
- Ohio State University (OSU), Davis Heart and Lung Research Institute, 473 W. 12th Ave, Suite 200, Columbus, OH 43210, USA
| | - Rebecca D Jackson
- OSU, Division of Endocrinology, Diabetes and Metabolism, 1581 Dodd Drive, Columbus, OH 43210, USA
| |
Collapse
|
123
|
Chistiakov DA, Orekhov AN, Bobryshev YV. Contribution of neovascularization and intraplaque haemorrhage to atherosclerotic plaque progression and instability. Acta Physiol (Oxf) 2015; 213:539-53. [PMID: 25515699 DOI: 10.1111/apha.12438] [Citation(s) in RCA: 75] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2014] [Revised: 11/13/2014] [Accepted: 12/10/2014] [Indexed: 12/14/2022]
Abstract
Atherosclerosis is a continuous pathological process that starts early in life and progresses frequently to unstable plaques. Plaque rupture leads to deleterious consequences such as acute coronary syndrome, stroke and atherothrombosis. The vulnerable lesion has several structural and functional hallmarks that distinguish it from the stable plaque. The unstable plaque has large necrotic core (over 40% plaque volume) composed of cholesterol crystals, cholesterol esters, oxidized lipids, fibrin, erythrocytes and their remnants (haeme, iron, haemoglobin), and dying macrophages. The fibrous cap is thin, depleted of smooth muscle cells and collagen, and is infiltrated with proinflammatory cells. In unstable lesion, formation of neomicrovessels is increased. These neovessels have weak integrity and leak thereby leading to recurrent haemorrhages. Haemorrhages deliver erythrocytes to the necrotic core where they degrade promoting inflammation and oxidative stress. Inflammatory cells mostly presented by monocytes/macrophages, neutrophils and mast cells extravagate from bleeding neovessels and infiltrate adventitia where they support chronic inflammation. Plaque destabilization is an evolutionary process that could start at early atherosclerotic stages and whose progression is influenced by many factors including neovascularization, intraplaque haemorrhages, formation of cholesterol crystals, inflammation, oxidative stress and intraplaque protease activity.
Collapse
Affiliation(s)
- D. A. Chistiakov
- Department of Medical Nanobiotechnology; Pirogov Russian State Medical University; Moscow Russia
- The Mount Sinai Community Clinical Oncology Program; Mount Sinai Comprehensive Cancer Center; Mount Sinai Medical Center; Miami Beach FL USA
- Research Center for Children's Health; Moscow Russia
| | - A. N. Orekhov
- Laboratory of Angiopathology; Institute of General Pathology and Pathophysiology; Russian Academy of Sciences; Moscow Russia
- Skolkovo Innovative Center; Institute for Atherosclerosis Research; Moscow Russia
| | - Y. V. Bobryshev
- Laboratory of Angiopathology; Institute of General Pathology and Pathophysiology; Russian Academy of Sciences; Moscow Russia
- Faculty of Medicine and St Vincent's Centre for Applied Medical Research; University of New South Wales; Sydney NSW Australia
- School of Medicine; University of Western Sydney; Campbelltown NSW Australia
| |
Collapse
|
124
|
Harper VM, Oh JY, Stapley R, Marques MB, Wilson L, Barnes S, Sun CW, Townes T, Patel RP. Peroxiredoxin-2 recycling is inhibited during erythrocyte storage. Antioxid Redox Signal 2015; 22:294-307. [PMID: 25264713 PMCID: PMC4298151 DOI: 10.1089/ars.2014.5950] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
AIMS Transfusion with stored red blood cells (RBCs) is associated with increased morbidity and mortality. Peroxiredoxin-2 (Prx-2) is a primary RBC antioxidant that limits hydrogen peroxide (H2O2)-mediated toxicity. Whether Prx-2 activity is altered during RBC storage is not known. RESULTS Basal and H2O2-induced Prx-2 activity was measured in RBCs (stored for 7-35 days). Basal Prx-2 thiol oxidation increased with RBC age, whereas H2O2-dependent formation of dimeric Prx-2 was similar. However, reduction of Prx-2 dimers to monomers became progressively slower with RBC storage, which was associated with increased H2O2-induced hemolysis. Surprisingly, no change in the NADPH-dependent thioredoxin (Trx)/Trx-reductase system, which recycles dimeric Prx-2, was observed in stored RBCs. Using mouse RBCs expressing human wild type (β93Cys) or hemoglobin (Hb) in which the conserved β93Cys residue is replaced by Ala (β93Ala), a role for this thiol in modulating Prx-2 reduction was demonstrated. Specifically, Prx-2 recycling was blunted in β93Ala RBC, which was reversed by carbon monoxide-treatment, suggesting that heme autoxidation-derived H2O2 maintains Prx-2 in the oxidized form in these cells. Moreover, assessment of the oxidative state of the β93Cys in RBCs during storage showed that while it remained reduced on intraerythrocytic Hb in stored RBC, it was oxidized to dehydroalanine on hemolyzed or extracellular Hb. INNOVATION A novel mechanism for regulated Prx-2 activity in RBC via the β93Cys residue is suggested. CONCLUSION These data highlight the potential for slower Prx-2 recycling and β93Cys oxidation in modulating storage-dependent damage of RBCs and in mediating post-transfusion toxicity.
Collapse
Affiliation(s)
- Victoria M Harper
- 1 Department of Pathology, University of Alabama at Birmingham , Birmingham, Alabama
| | | | | | | | | | | | | | | | | |
Collapse
|
125
|
Rifkind JM, Mohanty JG, Nagababu E. The pathophysiology of extracellular hemoglobin associated with enhanced oxidative reactions. Front Physiol 2015; 5:500. [PMID: 25642190 PMCID: PMC4294139 DOI: 10.3389/fphys.2014.00500] [Citation(s) in RCA: 106] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2014] [Accepted: 12/02/2014] [Indexed: 11/16/2022] Open
Abstract
Hemoglobin (Hb) continuously undergoes autoxidation producing superoxide which dismutates into hydrogen peroxide (H2O2) and is a potential source for subsequent oxidative reactions. Autoxidation is most pronounced under hypoxic conditions in the microcirculation and for unstable dimers formed at reduced Hb concentrations. In the red blood cell (RBC), oxidative reactions are inhibited by an extensive antioxidant system. For extracellular Hb, whether from hemolysis of RBCs and/or the infusion of Hb-based blood substitutes, the oxidative reactions are not completely neutralized by the available antioxidant system. Un-neutralized H2O2 oxidizes ferrous and ferric Hbs to Fe(IV)-ferrylHb and OxyferrylHb, respectively. FerrylHb further reacts with H2O2 producing heme degradation products and free iron. OxyferrylHb, in addition to Fe(IV) contains a free radical that can undergo additional oxidative reactions. Fe(III)Hb produced during Hb autoxidation also readily releases heme, an additional source for oxidative stress. These oxidation products are a potential source for oxidative reactions in the plasma, but to a greater extent when the lower molecular weight Hb dimers are taken up into cells and tissues. Heme and oxyferryl have been shown to have a proinflammatory effect further increasing their potential for oxidative stress. These oxidative reactions contribute to a number of pathological situations including atherosclerosis, kidney malfunction, sickle cell disease, and malaria. The toxic effects of extracellular Hb are of particular concern with hemolytic anemia where there is an increase in hemolysis. Hemolysis is further exacerbated in various diseases and their treatments. Blood transfusions are required whenever there is an appreciable decrease in RBCs due to hemolysis or blood loss. It is, therefore, essential that the transfused blood, whether stored RBCs or the blood obtained by an Autologous Blood Recovery System from the patient, do not further increase extracellular Hb.
Collapse
Affiliation(s)
- Joseph M Rifkind
- Molecular Dynamics Section, Laboratory of Molecular Gerontology, National Institute on Aging Baltimore, MD, USA ; Department of Anesthesiology and Critical Care Medicine, The Johns Hopkins Medical Institutions Baltimore, MD, USA
| | - Joy G Mohanty
- Molecular Dynamics Section, Laboratory of Molecular Gerontology, National Institute on Aging Baltimore, MD, USA
| | - Enika Nagababu
- Department of Anesthesiology and Critical Care Medicine, The Johns Hopkins Medical Institutions Baltimore, MD, USA
| |
Collapse
|
126
|
Veiner HL, Gorbatov R, Vardi M, Doros G, Miller-Lotan R, Zohar Y, Sabo E, Asleh R, Levy NS, Goldfarb LJ, Berk TA, Haas T, Shalom H, Suss-Toby E, Kam A, Kaplan M, Tamir R, Ziskind A, Levy AP. Pharmacogenomic interaction between the Haptoglobin genotype and vitamin E on atherosclerotic plaque progression and stability. Atherosclerosis 2015; 239:232-9. [PMID: 25618031 DOI: 10.1016/j.atherosclerosis.2015.01.008] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/09/2014] [Revised: 12/29/2014] [Accepted: 01/07/2015] [Indexed: 02/07/2023]
Abstract
OBJECTIVE Homozygosity for a 1.7 kb intragenic duplication of the Haptoglobin (Hp) gene (Hp 2-2 genotype), present in 36% of the population, has been associated with a 2-3 fold increased incidence of atherothrombosis in individuals with Diabetes (DM) in 10 longitudinal studies compared to DM individuals not homozygous for this duplication (Hp 1-1/2-1). The increased CVD risk associated with the Hp 2-2 genotype has been shown to be prevented with vitamin E supplementation in man. We sought to determine if there was an interaction between the Hp genotype and vitamin E on atherosclerotic plaque growth and stability in a transgenic model of the Hp polymorphism. METHODS AND RESULTS Brachiocephalic artery atherosclerotic plaque volume was serially assessed by high resolution ultrasound in 28 Hp 1-1 and 26 Hp 2-2 mice in a C57Bl/6 ApoE(-/-) background. Hp 2-2 mice had more rapid plaque growth and an increased incidence of plaque hemorrhage and rupture. Vitamin E significantly reduced plaque growth in Hp 2-2 but not in Hp 1-1 mice with a significant pharmacogenomic interaction between the Hp genotype and vitamin E on plaque growth. CONCLUSIONS These results may help explain why vitamin E supplementation in man can prevent CVD in Hp 2-2 DM but not in non Hp 2-2 DM individuals.
Collapse
Affiliation(s)
- Hilla-Lee Veiner
- Technion Faculty of Medicine, Technion Israel Institute of Technology, Haifa, Israel
| | - Rostic Gorbatov
- Technion Faculty of Medicine, Technion Israel Institute of Technology, Haifa, Israel
| | - Moshe Vardi
- Harvard Clinical Research Institute, Boston, MA, USA; Boston University School of Public Health, Boston, MA, USA
| | - Gheorghe Doros
- Harvard Clinical Research Institute, Boston, MA, USA; Boston University School of Public Health, Boston, MA, USA
| | - Rachel Miller-Lotan
- Technion Faculty of Medicine, Technion Israel Institute of Technology, Haifa, Israel
| | - Yaniv Zohar
- Technion Faculty of Medicine, Technion Israel Institute of Technology, Haifa, Israel
| | - Edmond Sabo
- Technion Faculty of Medicine, Technion Israel Institute of Technology, Haifa, Israel
| | - Rabea Asleh
- Technion Faculty of Medicine, Technion Israel Institute of Technology, Haifa, Israel
| | - Nina S Levy
- Technion Faculty of Medicine, Technion Israel Institute of Technology, Haifa, Israel
| | - Levi J Goldfarb
- Technion Faculty of Medicine, Technion Israel Institute of Technology, Haifa, Israel
| | - Thomas A Berk
- Technion Faculty of Medicine, Technion Israel Institute of Technology, Haifa, Israel; University of Toronto Faculty of Medicine, Toronto, Canada
| | - Tali Haas
- Technion Faculty of Medicine, Technion Israel Institute of Technology, Haifa, Israel
| | - Hadar Shalom
- Technion Faculty of Medicine, Technion Israel Institute of Technology, Haifa, Israel
| | - Edith Suss-Toby
- Technion Faculty of Medicine, Technion Israel Institute of Technology, Haifa, Israel
| | - Adi Kam
- Technion Faculty of Medicine, Technion Israel Institute of Technology, Haifa, Israel
| | | | | | | | - Andrew P Levy
- Technion Faculty of Medicine, Technion Israel Institute of Technology, Haifa, Israel.
| |
Collapse
|
127
|
Pretorius E, Kell DB. Diagnostic morphology: biophysical indicators for iron-driven inflammatory diseases. Integr Biol (Camb) 2014; 6:486-510. [PMID: 24714688 DOI: 10.1039/c4ib00025k] [Citation(s) in RCA: 108] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Most non-communicable diseases involve inflammatory changes in one or more vascular systems, and there is considerable evidence that unliganded iron plays major roles in this. Most studies concentrate on biochemical changes, but there are important biophysical correlates. Here we summarize recent microscopy-based observations to the effect that iron can have major effects on erythrocyte morphology, on erythrocyte deformability and on both fibrinogen polymerization and the consequent structure of the fibrin clots formed, each of which contributes significantly and negatively to such diseases. We highlight in particular type 2 diabetes mellitus, ischemic thrombotic stroke, systemic lupus erythematosus, hereditary hemochromatosis and Alzheimer's disease, while recognizing that many other diseases have co-morbidities (and similar causes). Inflammatory biomarkers such as ferritin and fibrinogen are themselves inflammatory, creating a positive feedback that exacerbates disease progression. The biophysical correlates we describe may provide novel, inexpensive and useful biomarkers of the therapeutic benefits of successful treatments.
Collapse
Affiliation(s)
- Etheresia Pretorius
- Department of Physiology, Faculty of Health Sciences, University of Pretoria, Private Bag x323, Arcadia 0007, South Africa.
| | | |
Collapse
|
128
|
Liu G, Mühlhäusler BS, Gibson RA. A method for long term stabilisation of long chain polyunsaturated fatty acids in dried blood spots and its clinical application. Prostaglandins Leukot Essent Fatty Acids 2014; 91:251-60. [PMID: 25451557 DOI: 10.1016/j.plefa.2014.09.009] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/10/2014] [Revised: 09/17/2014] [Accepted: 09/18/2014] [Indexed: 02/08/2023]
Abstract
Conventional assays of omega-3 long chain polyunsaturated fatty acid (n-3 LCPUFA) status in humans involve venous blood collection and expensive, multi-step processes that limit their usefulness as screening tools. This study aimed to develop a capillary dried blood spot (DBS) system capable of protecting n-3 LCPUFA from oxidation for up to 2 months at room temperature (20-25°C). We demonstrated that a DBS system comprising both an antioxidant and chelating agent on silica-gel coated paper prevented any significant change in the n-3 LCPUFA profile after 2 months. Our DBS assay was then tested in fifty subjects, and this demonstrated the presence of strong and significant correlations between the results obtained from the DBS system and those obtained from conventional measures for all fatty acids, in particular the n-3 LCPUFA EPA and DHA (r>0.96, P<0.0001). This study therefore validates our DBS system as a reliable method for the assessment of n-3 LCPUFA status in humans.
Collapse
Affiliation(s)
- Ge Liu
- FOODplus Research Centre, School of Agriculture, Food and Wine, University of Adelaide, Adelaide, South Australia, Australia
| | - Beverly Sara Mühlhäusler
- FOODplus Research Centre, School of Agriculture, Food and Wine, University of Adelaide, Adelaide, South Australia, Australia
| | - Robert Alan Gibson
- FOODplus Research Centre, School of Agriculture, Food and Wine, University of Adelaide, Adelaide, South Australia, Australia.
| |
Collapse
|
129
|
Hurks R, Kropman RH, Pennekamp CW, Hoefer IE, de Vries JPP, Pasterkamp G, Vink A, Moll FL. Popliteal artery aneurysms differ from abdominal aortic aneurysms in cellular topography and inflammatory markers. J Vasc Surg 2014; 60:1514-9. [DOI: 10.1016/j.jvs.2014.08.088] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2014] [Accepted: 08/17/2014] [Indexed: 10/24/2022]
|
130
|
Schaer DJ, Vinchi F, Ingoglia G, Tolosano E, Buehler PW. Haptoglobin, hemopexin, and related defense pathways-basic science, clinical perspectives, and drug development. Front Physiol 2014; 5:415. [PMID: 25389409 PMCID: PMC4211382 DOI: 10.3389/fphys.2014.00415] [Citation(s) in RCA: 201] [Impact Index Per Article: 20.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2014] [Accepted: 10/08/2014] [Indexed: 12/13/2022] Open
Abstract
Hemolysis, which occurs in many disease states, can trigger a diverse pathophysiologic cascade that is related to the specific biochemical activities of free Hb and its porphyrin component heme. Normal erythropoiesis and concomitant removal of senescent red blood cells (RBC) from the circulation occurs at rates of approximately 2 × 106 RBCs/second. Within this physiologic range of RBC turnover, a small fraction of hemoglobin (Hb) is released into plasma as free extracellular Hb. In humans, there is an efficient multicomponent system of Hb sequestration, oxidative neutralization and clearance. Haptoglobin (Hp) is the primary Hb-binding protein in human plasma, which attenuates the adverse biochemical and physiologic effects of extracellular Hb. The cellular receptor target of Hp is the monocyte/macrophage scavenger receptor, CD163. Following Hb-Hp binding to CD163, cellular internalization of the complex leads to globin and heme metabolism, which is followed by adaptive changes in antioxidant and iron metabolism pathways and macrophage phenotype polarization. When Hb is released from RBCs within the physiologic range of Hp, the potential deleterious effects of Hb are prevented. However, during hyper-hemolytic conditions or with chronic hemolysis, Hp is depleted and Hb readily distributes to tissues where it might be exposed to oxidative conditions. In such conditions, heme can be released from ferric Hb. The free heme can then accelerate tissue damage by promoting peroxidative reactions and activation of inflammatory cascades. Hemopexin (Hx) is another plasma glycoprotein able to bind heme with high affinity. Hx sequesters heme in an inert, non-toxic form and transports it to the liver for catabolism and excretion. In the present review we discuss the components of physiologic Hb/heme detoxification and their potential therapeutic application in a wide range of hemolytic conditions.
Collapse
Affiliation(s)
- Dominik J Schaer
- Division of Internal Medicine, University of Zurich Zurich, Switzerland
| | - Francesca Vinchi
- Department of Molecular Biotechnology and Health Sciences, University of Torino Torino, Italy
| | - Giada Ingoglia
- Department of Molecular Biotechnology and Health Sciences, University of Torino Torino, Italy
| | - Emanuela Tolosano
- Department of Molecular Biotechnology and Health Sciences, University of Torino Torino, Italy
| | - Paul W Buehler
- Division of Hematology, Laboratory of Biochemistry and Vascular Biology, Center for Biologics Evaluation and Research, Food and Drug Administration Bethesda, MD, USA
| |
Collapse
|
131
|
Bamm VV, Lanthier DK, Stephenson EL, Smith GST, Harauz G. In vitro study of the direct effect of extracellular hemoglobin on myelin components. Biochim Biophys Acta Mol Basis Dis 2014; 1852:92-103. [PMID: 25463632 DOI: 10.1016/j.bbadis.2014.10.009] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2014] [Revised: 09/26/2014] [Accepted: 10/09/2014] [Indexed: 01/04/2023]
Abstract
There is a relationship between cerebral vasculature and multiple sclerosis (MS) lesions: abnormal accumulations of iron have been found in the walls of dilated veins in MS plaques. The sources of this iron can be varied, but capillary and venous hemorrhages leading to blood extravasation have been recorded, and could result in the release of hemoglobin extracellularly. Extracellular hemoglobin oxidizes quickly and is known to become a reactive molecule that triggers low-density lipoprotein oxidation and plays a pivotal role in atherogenesis. In MS, it could lead to local oxidative stress, inflammation, and tissue damage. Here, we investigated whether extracellular hemoglobin and its breakdown products can cause direct oxidative damage to myelin components in a peroxidative environment such as occurs in inflamed tissue. Oxidation of lipids was assessed by the formation of fluorescent peroxidized lipid-protein covalent adducts, by the increase in conjugated diene and malondialdehyde. Oxidation of proteins was analyzed by the change in protein mass. The results suggest that the globin radical could be a trigger of myelin basic protein oxidative cross-linking, and that heme transferred to the lipids is involved in lipid peroxidation. This study provides new insight into the mechanism by which hemoglobin exerts its pathological oxidative activity towards myelin components. This work supports further research into the vascular pathology in MS, to gain insight into the origin and role of iron deposits in disease pathogenesis, or in stimulation of different comorbidities such as cardiovascular disease.
Collapse
Affiliation(s)
- Vladimir V Bamm
- Department of Molecular and Cellular Biology, University of Guelph, 50 Stone Road East, Guelph, Ontario N1G 2W1, Canada
| | - Danielle K Lanthier
- Department of Molecular and Cellular Biology, University of Guelph, 50 Stone Road East, Guelph, Ontario N1G 2W1, Canada
| | - Erin L Stephenson
- Department of Molecular and Cellular Biology, University of Guelph, 50 Stone Road East, Guelph, Ontario N1G 2W1, Canada
| | - Graham S T Smith
- Department of Molecular and Cellular Biology, University of Guelph, 50 Stone Road East, Guelph, Ontario N1G 2W1, Canada
| | - George Harauz
- Department of Molecular and Cellular Biology, University of Guelph, 50 Stone Road East, Guelph, Ontario N1G 2W1, Canada.
| |
Collapse
|
132
|
Jeney V, Balla G, Balla J. Red blood cell, hemoglobin and heme in the progression of atherosclerosis. Front Physiol 2014; 5:379. [PMID: 25324785 PMCID: PMC4183119 DOI: 10.3389/fphys.2014.00379] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2014] [Accepted: 09/13/2014] [Indexed: 01/02/2023] Open
Abstract
For decades plaque neovascularization was considered as an innocent feature of advanced atherosclerotic lesions, but nowadays growing evidence suggest that this process triggers plaque progression and vulnerability. Neovascularization is induced mostly by hypoxia, but the involvement of oxidative stress is also established. Because of inappropriate angiogenesis, neovessels are leaky and prone to rupture, leading to the extravasation of red blood cells (RBCs) within the plaque. RBCs, in the highly oxidative environment of the atherosclerotic lesions, tend to lyse quickly. Both RBC membrane and the released hemoglobin (Hb) possess atherogenic activities. Cholesterol content of RBC membrane contributes to lipid deposition and lipid core expansion upon intraplaque hemorrhage. Cell-free Hb is prone to oxidation, and the oxidation products possess pro-oxidant and pro-inflammatory activities. Defense and adaptation mechanisms evolved to cope with the deleterious effects of cell free Hb and heme. These rely on plasma proteins haptoglobin (Hp) and hemopexin (Hx) with the ability to scavenge and eliminate free Hb and heme form the circulation. The protective strategy is completed with the cellular heme oxygenase-1/ferritin system that becomes activated when Hp and Hx fail to control free Hb and heme-mediated stress. These protective molecules have pharmacological potential in diverse pathologies including atherosclerosis.
Collapse
Affiliation(s)
- Viktória Jeney
- Department of Medicine, University of Debrecen Debrecen, Hungary ; MTA-DE Vascular Biology, Thrombosis and Hemostasis Research Group, Hungarian Academy of Sciences Debrecen, Hungary
| | - György Balla
- MTA-DE Vascular Biology, Thrombosis and Hemostasis Research Group, Hungarian Academy of Sciences Debrecen, Hungary ; Department of Pediatrics, University of Debrecen Debrecen, Hungary
| | - József Balla
- Department of Medicine, University of Debrecen Debrecen, Hungary
| |
Collapse
|
133
|
Nairz M, Schroll A, Demetz E, Tancevski I, Theurl I, Weiss G. 'Ride on the ferrous wheel'--the cycle of iron in macrophages in health and disease. Immunobiology 2014; 220:280-94. [PMID: 25240631 DOI: 10.1016/j.imbio.2014.09.010] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2014] [Revised: 08/20/2014] [Accepted: 09/05/2014] [Indexed: 12/16/2022]
Abstract
Iron homeostasis and macrophage biology are closely interconnected. On the one hand, iron exerts multiple effects on macrophage polarization and functionality. On the other hand, macrophages are central for mammalian iron homeostasis. The phagocytosis of senescent erythrocytes and their degradation by macrophages enable efficient recycling of iron and the maintenance of systemic iron balance. Macrophages express multiple molecules and proteins for the acquisition and utilization of iron and many of these pathways are affected by inflammatory signals. Of note, iron availability within macrophages has significant effects on immune effector functions and metabolic pathways within these cells. This review summarizes the physiological and pathophysiological aspects of macrophage iron metabolism and highlights its relevant consequences on immune function and in common diseases such as infection and atherosclerosis.
Collapse
Affiliation(s)
- Manfred Nairz
- Department of Internal Medicine VI, Infectious Diseases, Immunology, Rheumatology, Pneumology, Medical University of Innsbruck, Austria.
| | - Andrea Schroll
- Department of Internal Medicine VI, Infectious Diseases, Immunology, Rheumatology, Pneumology, Medical University of Innsbruck, Austria
| | - Egon Demetz
- Department of Internal Medicine VI, Infectious Diseases, Immunology, Rheumatology, Pneumology, Medical University of Innsbruck, Austria
| | - Ivan Tancevski
- Department of Internal Medicine VI, Infectious Diseases, Immunology, Rheumatology, Pneumology, Medical University of Innsbruck, Austria
| | - Igor Theurl
- Department of Internal Medicine VI, Infectious Diseases, Immunology, Rheumatology, Pneumology, Medical University of Innsbruck, Austria
| | - Günter Weiss
- Department of Internal Medicine VI, Infectious Diseases, Immunology, Rheumatology, Pneumology, Medical University of Innsbruck, Austria.
| |
Collapse
|
134
|
Habib A, Finn AV. The role of iron metabolism as a mediator of macrophage inflammation and lipid handling in atherosclerosis. Front Pharmacol 2014; 5:195. [PMID: 25221512 PMCID: PMC4145350 DOI: 10.3389/fphar.2014.00195] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2014] [Accepted: 08/04/2014] [Indexed: 12/19/2022] Open
Abstract
Iron is an essential mineral needed for normal physiologic processes. While its function in oxygen transport and other important physiologic processes is well known, less is understood about its role in inflammatory diseases such as atherosclerosis. Existing paradigms suggest iron as a driver of atherosclerosis through its actions as a pro-oxidant capable of causing lipid oxidation and tissue damage. Recently we and others have identified hemoglobin (Hb) derived iron as an important factor in determining macrophage differentiation and function in areas of intraplaque hemorrhage within human atherosclerosis. Hb associated macrophages, M(Hb), are distinct from traditional macrophage foam cells because they do not contain large amounts of lipid or inflammatory cytokines, are characterized by high levels of expression of mannose receptor (CD206) and CD163 in addition to producing anti-inflammatory cytokines such as IL-10. Despite the well-known role of iron as an catalyst capable of producing lipid peroxidation through generation of reactive oxygen species (ROS) such as hydroxyl radical, we and others have shown that macrophages in areas of intraplaque hemorrhage demonstrate reduced intracellular iron and ROS which triggers production of anti-inflammatory cytokines as well as genes involved in cholesterol efflux. These data suggest that manipulation of macrophage iron itself may be a promising pharmacologic target for atherosclerosis prevention through its effects on macrophage inflammation and lipid metabolism. In this review we will summarize the current understanding of iron as it relates to plaque inflammation and discuss how further exploration of this subject may lead to new therapies for atherosclerosis.
Collapse
Affiliation(s)
- Anwer Habib
- Division of Cardiology, Department of Medicine, Emory University School of Medicine, Atlanta, GA USA
| | - Aloke V Finn
- Division of Cardiology, Department of Medicine, Emory University School of Medicine, Atlanta, GA USA
| |
Collapse
|
135
|
Sher EA, Sholto AY, Shaklai M, Shaklai N. Can gas replace protein function? CO abrogates the oxidative toxicity of myoglobin. PLoS One 2014; 9:e104075. [PMID: 25111140 PMCID: PMC4128816 DOI: 10.1371/journal.pone.0104075] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2014] [Accepted: 07/06/2014] [Indexed: 02/07/2023] Open
Abstract
Outside their cellular environments, hemoglobin (Hb) and myoglobin (Mb) are known to wreak oxidative damage. Using haptoglobin (Hp) and hemopexin (Hx) the body defends itself against cell-free Hb, yet mechanisms of protection against oxidative harm from Mb are unclear. Mb may be implicated in oxidative damage both within the myocyte and in circulation following rhabdomyolysis. Data from the literature correlate rhabdomyolysis with the induction of Heme Oxygenase-1 (HO-1), suggesting that either the enzyme or its reaction products are involved in oxidative protection. We hypothesized that carbon monoxide (CO), a product, might attenuate Mb damage, especially since CO is a specific ligand for heme iron. Low density lipoprotein (LDL) was chosen as a substrate in circulation and myosin (My) as a myocyte component. Using oxidation targets, LDL and My, the study compared the antioxidant potential of CO in Mb-mediated oxidation with the antioxidant potential of Hp in Hb-mediated oxidation. The main cause of LDL oxidation by Hb was found to be hemin which readily transfers from Hb to LDL. Hp prevented heme transfer by sequestering hemin within the Hp-Hb complex. Hemin barely transferred from Mb to LDL, and oxidation appeared to stem from heme iron redox in the intact Mb. My underwent oxidative crosslinking by Mb both in air and under N2. These reactions were fully arrested by CO. The data are interpreted to suit several circumstances, some physiological, such as high muscle activity, and some pathological, such as rhabdomyolysis, ischemia/reperfusion and skeletal muscle disuse atrophy. It appear that CO from HO-1 attenuates damage by temporarily binding to deoxy-Mb, until free oxygen exchanges with CO to restore the equilibrium.
Collapse
Affiliation(s)
- Elena A. Sher
- Department of Human Genetics and Biochemistry, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Alan Y. Sholto
- Department of Human Genetics and Biochemistry, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Mati Shaklai
- Department of Human Genetics and Biochemistry, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Nurith Shaklai
- Department of Hematology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
- * E-mail:
| |
Collapse
|
136
|
Affiliation(s)
- Mary Jo Mulligan-Kehoe
- From the Department of Surgery, Vascular Section, Geisel School of Medicine at Dartmouth, Lebanon, NH (M.J.M.-K.); and Yale Cardiovascular Research Center, Section of Cardiovascular Medicine, Department of Internal Medicine, Yale University School of Medicine, New Haven, CT (M.S.)
| | - Michael Simons
- From the Department of Surgery, Vascular Section, Geisel School of Medicine at Dartmouth, Lebanon, NH (M.J.M.-K.); and Yale Cardiovascular Research Center, Section of Cardiovascular Medicine, Department of Internal Medicine, Yale University School of Medicine, New Haven, CT (M.S.)
| |
Collapse
|
137
|
Dutra FF, Bozza MT. Heme on innate immunity and inflammation. Front Pharmacol 2014; 5:115. [PMID: 24904418 PMCID: PMC4035012 DOI: 10.3389/fphar.2014.00115] [Citation(s) in RCA: 225] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2014] [Accepted: 04/29/2014] [Indexed: 12/30/2022] Open
Abstract
Heme is an essential molecule expressed ubiquitously all through our tissues. Heme plays major functions in cellular physiology and metabolism as the prosthetic group of diverse proteins. Once released from cells and from hemeproteins free heme causes oxidative damage and inflammation, thus acting as a prototypic damage-associated molecular pattern. In this context, free heme is a critical component of the pathological process of sterile and infectious hemolytic conditions including malaria, hemolytic anemias, ischemia-reperfusion, and hemorrhage. The plasma scavenger proteins hemopexin and albumin reduce heme toxicity and are responsible for transporting free heme to intracellular compartments where it is catabolized by heme-oxygenase enzymes. Upon hemolysis or severe cellular damage the serum capacity to scavenge heme may saturate and increase free heme to sufficient amounts to cause tissue damage in various organs. The mechanism by which heme causes reactive oxygen generation, activation of cells of the innate immune system and cell death are not fully understood. Although heme can directly promote lipid peroxidation by its iron atom, heme can also induce reactive oxygen species generation and production of inflammatory mediators through the activation of selective signaling pathways. Heme activates innate immune cells such as macrophages and neutrophils through activation of innate immune receptors. The importance of these events has been demonstrated in infectious and non-infectious diseases models. In this review, we will discuss the mechanisms behind heme-induced cytotoxicity and inflammation and the consequences of these events on different tissues and diseases.
Collapse
Affiliation(s)
- Fabianno F. Dutra
- Laboratório de Inflamação e Imunidade, Departamento de Imunologia, Instituto de Microbiologia, Universidade Federal do Rio de JaneiroRio de Janeiro, Brazil
| | - Marcelo T. Bozza
- Laboratório de Inflamação e Imunidade, Departamento de Imunologia, Instituto de Microbiologia, Universidade Federal do Rio de JaneiroRio de Janeiro, Brazil
| |
Collapse
|
138
|
Vinchi F, Muckenthaler MU, Da Silva MC, Balla G, Balla J, Jeney V. Atherogenesis and iron: from epidemiology to cellular level. Front Pharmacol 2014; 5:94. [PMID: 24847266 PMCID: PMC4017151 DOI: 10.3389/fphar.2014.00094] [Citation(s) in RCA: 106] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2014] [Accepted: 04/14/2014] [Indexed: 12/12/2022] Open
Abstract
Iron accumulates in human atherosclerotic lesions but whether it is a cause or simply a downstream consequence of the atheroma formation has been an open question for decades. According to the so called "iron hypothesis," iron is believed to be detrimental for the cardiovascular system, thus promoting atherosclerosis development and progression. Iron, in its catalytically active form, can participate in the generation of reactive oxygen species and induce lipid-peroxidation, triggering endothelial activation, smooth muscle cell proliferation and macrophage activation; all of these processes are considered to be proatherogenic. On the other hand, the observation that hemochromatotic patients, affected by life-long iron overload, do not show any increased incidence of atherosclerosis is perceived as the most convincing evidence against the "iron hypothesis." Epidemiological studies and data from animal models provided conflicting evidences about the role of iron in atherogenesis. Therefore, more careful studies are needed in which issues like the source and the compartmentalization of iron will be addressed. This review article summarizes what we have learnt about iron and atherosclerosis from epidemiological studies, animal models and cellular systems and highlights the rather contributory than innocent role of iron in atherogenesis.
Collapse
Affiliation(s)
- Francesca Vinchi
- Department of Pediatric Oncology, Hematology and Immunology, University of Heidelberg Heidelberg, Germany ; Molecular Medicine and Partnership Unit, University of Heidelberg Heidelberg, Germany
| | - Martina U Muckenthaler
- Department of Pediatric Oncology, Hematology and Immunology, University of Heidelberg Heidelberg, Germany ; Molecular Medicine and Partnership Unit, University of Heidelberg Heidelberg, Germany
| | - Milene C Da Silva
- Department of Pediatric Oncology, Hematology and Immunology, University of Heidelberg Heidelberg, Germany ; Molecular Medicine and Partnership Unit, University of Heidelberg Heidelberg, Germany
| | - György Balla
- MTA-DE Vascular Biology, Thrombosis and Hemostasis Research Group, Hungarian Academy of Sciences Debrecen, Hungary ; Department of Pediatrics, University of Debrecen Debrecen, Hungary
| | - József Balla
- Department of Medicine, University of Debrecen Debrecen, Hungary
| | - Viktória Jeney
- MTA-DE Vascular Biology, Thrombosis and Hemostasis Research Group, Hungarian Academy of Sciences Debrecen, Hungary ; Department of Medicine, University of Debrecen Debrecen, Hungary
| |
Collapse
|
139
|
Bamm VV, Harauz G. Hemoglobin as a source of iron overload in multiple sclerosis: does multiple sclerosis share risk factors with vascular disorders? Cell Mol Life Sci 2014; 71:1789-98. [PMID: 24504127 PMCID: PMC11113400 DOI: 10.1007/s00018-014-1570-y] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2013] [Revised: 01/16/2014] [Accepted: 01/20/2014] [Indexed: 12/12/2022]
Abstract
Although iron is known to be essential for the normal development and health of the central nervous system, abnormal iron deposits are found in and around multiple sclerosis (MS) lesions that themselves are closely associated with the cerebral vasculature. However, the origin of this excess iron is unknown, and it is not clear whether this is one of the primary causative events in the pathogenesis of MS, or simply another consequence of the long-lasting inflammatory conditions. Here, applying a systems biology approach, we propose an additional way for understanding the neurodegenerative component of the disease caused by chronic subclinical extravasation of hemoglobin, in combination with multiple other factors including, but not limited to, dysfunction of different cellular protective mechanisms against extracellular hemoglobin reactivity and oxidative stress. Moreover, such considerations could also shed light on and explain the higher susceptibility of MS patients to a wide range of cardiovascular disorders.
Collapse
Affiliation(s)
- Vladimir V. Bamm
- Department of Molecular and Cellular Biology, University of Guelph, 50 Stone Road East, Guelph, ON N1G 2W1 Canada
| | - George Harauz
- Department of Molecular and Cellular Biology, University of Guelph, 50 Stone Road East, Guelph, ON N1G 2W1 Canada
| |
Collapse
|
140
|
Kuypers FA. Hemoglobin S Polymerization and Red Cell Membrane Changes. Hematol Oncol Clin North Am 2014; 28:155-79. [DOI: 10.1016/j.hoc.2013.12.002] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
|
141
|
Michel JB, Martin-Ventura JL, Nicoletti A, Ho-Tin-Noé B. Pathology of human plaque vulnerability: mechanisms and consequences of intraplaque haemorrhages. Atherosclerosis 2014; 234:311-9. [PMID: 24726899 DOI: 10.1016/j.atherosclerosis.2014.03.020] [Citation(s) in RCA: 119] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2013] [Revised: 03/04/2014] [Accepted: 03/17/2014] [Indexed: 02/07/2023]
Abstract
Atherothrombotic diseases are still major causes of inability and mortality and fighting atherothrombosis remains a public health priority. The involvement of repeated intraplaque haemorrhages (IPH) in the evolution of atherothrombotic lesions towards complications was proposed as early as 1936. This important topic has been recently revisited and reviewed. Histological observations have been corroborated by magnetic resonance imaging (MRI) of human carotid atheroma, identifying IPH as the main determinant of plaque evolution towards rupture. Beside the intimal integration of asymptomatic luminal coagulum, inward sprouting of neovessels from the adventitia towards the plaque, is one source of IPH in human atheroma. We recently described that directed neo-angiogenesis from the adventitia towards the plaque, across the media, is initiated by lipid mediators generated by the plaque on the luminal side, outwardly convected to the medial VSMCs. Subsequent stimulation of VSMC PPAR-γ receptors induces VEGF expression which causes centripetal sprouting of adventitial vessels. However, this neovascularization is considered to be immature and highly susceptible to leakage. The main cellular components of IPH are Red Blood Cells (RBCs), which with their haemoglobin content and their cell membrane components, particularly enriched in unesterified cholesterol, participate in both the oxidative process and cholesterol accumulation. The presence of iron, glycophorin A and ceroids provides evidence of RBCs. IPH also convey blood leukocytes and platelets and are sites prone to weak pathogen contamination. Therefore prevention and treatment of the biological consequences of IPH pave the way to innovative preventive strategies and improved therapeutic options in human atherothrombotic diseases.
Collapse
Affiliation(s)
| | | | - Antonino Nicoletti
- UMR 1148 Inserm-Paris7 University, Xavier Bichat Hospital, 75018 Paris, France
| | - Benoit Ho-Tin-Noé
- UMR 1148 Inserm-Paris7 University, Xavier Bichat Hospital, 75018 Paris, France
| |
Collapse
|
142
|
Lipinski B, Pretorius E. Iron-induced fibrin in cardiovascular disease. Curr Neurovasc Res 2014; 10:269-74. [PMID: 23721262 PMCID: PMC3763776 DOI: 10.2174/15672026113109990016] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2013] [Revised: 05/22/2013] [Accepted: 05/24/2013] [Indexed: 01/19/2023]
Abstract
Accumulating evidence within the last two decades indicates the association between cardiovascular disease (CVD) and chronic inflammatory state. Under normal conditions fibrin clots are gradually degraded by the fibrinolytic enzyme system, so no permanent insoluble deposits remain in the circulation. However, fibrinolytic therapy in coronary and cerebral thrombosis is ineffective unless it is installed within 3-5 hours of the onset. We have shown that trivalent iron (FeIII) initiates a hydroxyl radical-catalyzed conversion of fibrinogen into a fibrin-like polymer (parafibrin) that is remarkably resistant to the proteolytic dissolution and thus promotes its intravascular deposition. Here we suggest that the persistent presence of proteolysis-resistant fibrin clots causes chronic inflammation. We study the effects of certain amphiphilic substances on the iron- and thrombin-induced fibrinogen polymerization visualized using scanning electron microscopy. We argue that the culprit is an excessive accumulation of free iron in blood, known to be associated with CVD. The only way to prevent iron overload is by supplementation with iron chelating agents. However, administration of free radical scavengers as effective protection against persistent presence of fibrin-like deposits should also be investigated to contribute to the prevention of cardiovascular and other degenerative diseases.
Collapse
Affiliation(s)
- Boguslaw Lipinski
- Joslin Diabetes Center, Harvard Medical School, Boston, MA 02215, USA
| | | |
Collapse
|
143
|
Iron and atherosclerosis: nailing down a novel target with magnetic resonance. J Cardiovasc Transl Res 2014; 7:533-42. [PMID: 24590608 DOI: 10.1007/s12265-014-9551-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/14/2013] [Accepted: 02/14/2014] [Indexed: 12/21/2022]
Abstract
Iron is an essential mineral in many proteins and enzymes in human physiology, with limited means of iron elimination to maintain iron balance. Iron accrual incurs various pathological mechanisms linked to cardiovascular disease. In atherosclerosis, iron catalyzes the creation of reactive oxygen free radicals that contribute to lipid modification, which is essential to atheroma formation. Inflammation further fuels iron-related pathologic processes associated with plaque progression. Given iron's role in atherosclerosis development, in vivo detection techniques sensitive iron are needed for translational studies targeting iron for earlier diagnosis and treatment. Magnetic resonance imaging is uniquely able to quantify iron in human tissues noninvasively and without ionizing radiation, offering appealing for longitudinal and interventional studies. Particularly intriguing is iron's complementary biology vs. calcium, which is readily detectable by computed tomography. This review summarizes the role of iron in atherosclerosis with considerable implications for novel diagnostic and therapeutic approaches.
Collapse
|
144
|
Sato T, Kameyama T, Noto T, Inoue H. Impaired macrophage production of anti-atherosclerotic interleukin-10 induced by coronary intraplaque hemorrhage in patients with acute coronary syndrome and hyperglycemia. J Diabetes Complications 2014; 28:196-202. [PMID: 24239333 DOI: 10.1016/j.jdiacomp.2013.10.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/09/2013] [Revised: 10/08/2013] [Accepted: 10/09/2013] [Indexed: 12/13/2022]
Abstract
BACKGROUND Coronary intraplaque hemorrhage (IPH) accelerates atherosclerosis. Extracellular hemoglobin (Hb) released by IPH is cleared by macrophages with CD163 receptors. This process provokes secretion of the anti-atherosclerotic cytokine interleukin (IL)-10. The present study aimed to investigate the relationship between macrophage accumulation and IL-10 production provoked by IPH in plaques obtained from acute coronary syndrome (ACS) patients with hyperglycemia. METHODS In 50 ACS patients, atherothrombotic debris was retrieved during percutaneous coronary intervention (PCI). The debris was stained with antibodies to CD163, glycophorin A (GPA, a marker of IPH) and IL-10. %CD163 was defined as the ratios of CD163-positive cells to all cells. %IL-10 and %GPA were defined as the ratio of positively stained areas per total tissue area. Based on glycosylated Hb [HbA1c (NGSP)] ≥ 6.5%, fasting blood sugar (FBS) ≥ 126 mg/dL, and insulin resistance (HOMA-IR>2.5), patients were divided into a diabetes mellitus (DM) group (N = 18, HbA1c ≥ 6.5% or FBS ≥ 126 mg/dL), an insulin resistance (IR) group (N = 15, HOMA-IR>2.5, HbA1c<6.5%, and FBS< 126 mg/dL), and a normal (NR) group (N = 17). RESULTS Compared to the NR group, %GPA and %CD163 were increased in the DM and IR groups. %IL-10 was similar among the three groups. However, %IL-10/%CD163 ratios were decreased in the DM (2.5 ± 0.6, P = 0.01) and IR (2.7 ± 0.8, P = 0.02) groups compared to the NR group (5.8 ± 4.7). Only in the NR group was there a significant correlation between %IL-10 and %CD163. CONCLUSIONS Impairment of the anti-inflammatory effect provoked by IPH contributes to premature atherosclerosis even in the IR group.
Collapse
Affiliation(s)
- Takao Sato
- The Second Department of Internal Medicine, University of Toyama, Toyama, Japan.
| | - Tomoki Kameyama
- The Second Department of Internal Medicine, University of Toyama, Toyama, Japan
| | | | - Hiroshi Inoue
- The Second Department of Internal Medicine, University of Toyama, Toyama, Japan
| |
Collapse
|
145
|
Bastarache JA, Roberts LJ, Ware LB. Thinking outside the cell: how cell-free hemoglobin can potentiate acute lung injury. Am J Physiol Lung Cell Mol Physiol 2014; 306:L231-2. [PMID: 24337924 PMCID: PMC3920200 DOI: 10.1152/ajplung.00355.2013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2013] [Accepted: 12/09/2013] [Indexed: 11/22/2022] Open
|
146
|
Pretorius E, Bester J, Vermeulen N, Lipinski B, Gericke GS, Kell DB. Profound morphological changes in the erythrocytes and fibrin networks of patients with hemochromatosis or with hyperferritinemia, and their normalization by iron chelators and other agents. PLoS One 2014; 9:e85271. [PMID: 24416376 PMCID: PMC3887013 DOI: 10.1371/journal.pone.0085271] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2013] [Accepted: 11/25/2013] [Indexed: 12/22/2022] Open
Abstract
It is well-known that individuals with increased iron levels are more prone to thrombotic diseases, mainly due to the presence of unliganded iron, and thereby the increased production of hydroxyl radicals. It is also known that erythrocytes (RBCs) may play an important role during thrombotic events. Therefore the purpose of the current study was to assess whether RBCs had an altered morphology in individuals with hereditary hemochromatosis (HH), as well as some who displayed hyperferritinemia (HF). Using scanning electron microscopy, we also assessed means by which the RBC and fibrin morphology might be normalized. An important objective was to test the hypothesis that the altered RBC morphology was due to the presence of excess unliganded iron by removing it through chelation. Very striking differences were observed, in that the erythrocytes from HH and HF individuals were distorted and had a much greater axial ratio compared to that accompanying the discoid appearance seen in the normal samples. The response to thrombin, and the appearance of a platelet-rich plasma smear, were also markedly different. These differences could largely be reversed by the iron chelator desferal and to some degree by the iron chelator clioquinol, or by the free radical trapping agents salicylate or selenite (that may themselves also be iron chelators). These findings are consistent with the view that the aberrant morphology of the HH and HF erythrocytes is caused, at least in part, by unliganded (‘free’) iron, whether derived directly via raised ferritin levels or otherwise, and that lowering it or affecting the consequences of its action may be of therapeutic benefit. The findings also bear on the question of the extent to which accepting blood donations from HH individuals may be desirable or otherwise.
Collapse
Affiliation(s)
- Etheresia Pretorius
- Department of Physiology, University of Pretoria, Arcadia, South Africa
- * E-mail:
| | - Janette Bester
- Department of Physiology, University of Pretoria, Arcadia, South Africa
| | - Natasha Vermeulen
- Department of Physiology, University of Pretoria, Arcadia, South Africa
| | - Boguslaw Lipinski
- Joslin Diabetes Center, Harvard Medical School, Boston, Massachusetts, United States of America
| | | | - Douglas B. Kell
- School of Chemistry and The Manchester Institute of Biotechnology, The University of Manchester, Lancs, United Kingdom
| |
Collapse
|
147
|
Tan Y, Liu TR, Hu SW, Tian D, Li C, Zhong JK, Sun HG, Luo TT, Lai WY, Guo ZG. Acute coronary syndrome remodels the protein cargo and functions of high-density lipoprotein subfractions. PLoS One 2014; 9:e94264. [PMID: 24736723 PMCID: PMC3988065 DOI: 10.1371/journal.pone.0094264] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2013] [Accepted: 03/13/2014] [Indexed: 12/31/2022] Open
Abstract
OBJECTIVES This study examined alterations in the functions and proteome of high-density lipoprotein (HDL) subfractions (HDL2 and HDL3) isolated from patients with acute coronary syndrome (ACS) compared with control subjects. METHODS We measured HDL subfraction cholesterol efflux capacity, inflammatory index (HII), paraoxonase-1 (PON1) activity, and lipid hydroperoxide (LOOH) levels in both male age-matched controls and the ACS group (n = 40/group). Additionally, proteomic analysis was used to monitor changes in the HDL subfraction proteome between controls and ACS subjects. RESULTS Both HDL2 and HDL3 from ACS patients had greater HII and LOOH levels compared with controls (P<0.001); PON1 activity and cholesterol efflux capacity in both HDL2 and HDL3 from the ACS group were significantly less than those of controls (P<0.001). Using proteomic analysis, we demonstrated that, compared with the control group, nine proteins were selectively enriched in HDL3 from subjects with ACS, and ras-related protein Rab-7b was decreased in HDL3. Additionally, in the ACS subjects, 12 proteins were decreased in HDL2 and 4 proteins were increased in HDL2. CONCLUSIONS Functional HDL subfractions shifted to dysfunctional HDL subfractions during ACS, and the functional impairment was linked to remodeled protein cargo in HDL subfractions from ACS patients.
Collapse
Affiliation(s)
- Ying Tan
- Division of Cardiology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, P.R. China
| | - Ting Rong Liu
- Division of Cardiology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, P.R. China
| | - Shui Wang Hu
- Laboratory of Pathophysiology, Southern Medical University, Guangzhou, Guangdong, P.R. China
| | - Di Tian
- Division of Cardiology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, P.R. China
| | - Chen Li
- Division of Cardiology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, P.R. China
| | - Jian Kai Zhong
- Division of Cardiology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, P.R. China
| | - Hai Ge Sun
- Division of Cardiology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, P.R. China
| | - Tian Tian Luo
- Division of Cardiology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, P.R. China
| | - Wen Yan Lai
- Division of Cardiology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, P.R. China
| | - Zhi-Gang Guo
- Division of Cardiology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, P.R. China
- * E-mail:
| |
Collapse
|
148
|
Asselin C, Ducharme A, Ntimbane T, Ruiz M, Fortier A, Guertin MC, Lavoie J, Diaz A, Levy É, Tardif JC, Des Rosiers C. Circulating levels of linoleic acid and HDL-cholesterol are major determinants of 4-hydroxynonenal protein adducts in patients with heart failure. Redox Biol 2013; 2:148-55. [PMID: 24494189 PMCID: PMC3909262 DOI: 10.1016/j.redox.2013.12.009] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2013] [Accepted: 12/10/2013] [Indexed: 02/07/2023] Open
Abstract
OBJECTIVE Measurements of oxidative stress biomarkers in patients with heart failure (HF) have yielded controversial results. This study aimed at testing the hypothesis that circulating levels of the lipid peroxidation product 4-hydroxynonenal bound to thiol proteins (4HNE-P) are strongly associated with those of its potential precursors, namely n-6 polyunsaturated fatty acids (PUFA). METHODS AND RESULTS Circulating levels of 4HNE-P were evaluated by gas chromatography-mass spectrometry in 71 control subjects and 61 ambulatory symptomatic HF patients along with various other clinically- and biochemically-relevant parameters, including other oxidative stress markers, and total levels of fatty acids from all classes, which reflect both free and bound to cholesterol, phospholipids and triglycerides. All HF patients had severe systolic functional impairment despite receiving optimal evidence-based therapies. Compared to controls, HF patients displayed markedly lower circulating levels of HDL- and LDL-cholesterol, which are major PUFA carriers, as well as of PUFA of the n-6 series, specifically linoleic acid (LA; P=0.001). Circulating 4HNE-P in HF patients was similar to controls, albeit multiple regression analysis revealed that LA was the only factor that was significantly associated with circulating 4HNE-P in the entire population (R (2)=0.086; P=0.02). In HF patients only, 4HNE-P was even more strongly associated with LA (P=0.003) and HDL-cholesterol (p<0.0002). Our results demonstrate that 4HNE-P levels, expressed relative to HDL-cholesterol, increase as HDL-cholesterol plasma levels decrease in the HF group only. CONCLUSION Results from this study emphasize the importance of considering changes in lipids and lipoproteins in the interpretation of measurements of lipid peroxidation products. Further studies appear warranted to explore the possibility that HDL-cholesterol particles may be a carrier of 4HNE adducts.
Collapse
Key Words
- 4-Hydroxynnonenal
- 4HNE, 4-hydroxynonenal
- 4HNE-P, 4-hydroxynonenal bound to circulating thiol proteins
- AA, arachidonic acid
- CRP, C-reactive protein
- DHA, docosahexanaenoic acid
- EPA, eicosapentaenoic acid
- GSH, reduced glutathione
- GSSG, oxidized glutathione
- HF, heart failure
- HFC-MHI, heart failure clinic of the Montreal Heart Institute
- HOMA-IR, homeostatic model assessment of insulin resistance
- Heart failure patients
- LA, linoleic acid
- Linoleic acid
- Lipid peroxidation
- MDA, malondialdehyde
- MPO, myeloperoxidase
- NT-pro-BNP, N-terminal proB-type natriuretic peptide
- NYHA, New York Heart Association
- Oxidative stress
- PUFA, polyunsaturated fatty acids
- Polyunsaturated fatty acids
- RAS, renin-angiotensin system
- TBARS, thiobarbituric acid-reactive substances
- TNF, tumor necrosis factor
- eGFR, estimated glomerular filtration rate
Collapse
Affiliation(s)
- Caroline Asselin
- Montreal Heart Institute, Research Center, 5000 Belanger Street, Montreal, Quebec, Canada H1T 1C8
| | - Anique Ducharme
- Department of Medicine, Université de Montréal, Montreal, Quebec, Canada
- Montreal Heart Institute, Research Center, 5000 Belanger Street, Montreal, Quebec, Canada H1T 1C8
| | - Thierry Ntimbane
- Department of Nutrition, Université de Montréal, Montreal, Quebec, Canada
- Montreal Heart Institute, Research Center, 5000 Belanger Street, Montreal, Quebec, Canada H1T 1C8
| | - Matthieu Ruiz
- Department of Nutrition, Université de Montréal, Montreal, Quebec, Canada
- Montreal Heart Institute, Research Center, 5000 Belanger Street, Montreal, Quebec, Canada H1T 1C8
| | - Annik Fortier
- Montreal Heart Institute Coordinating Center, Montreal, Quebec, Canada
| | | | - Joël Lavoie
- Montreal Heart Institute, Research Center, 5000 Belanger Street, Montreal, Quebec, Canada H1T 1C8
| | - Ariel Diaz
- Department of Medicine, Université de Montréal, Montreal, Quebec, Canada
- Montreal Heart Institute, Research Center, 5000 Belanger Street, Montreal, Quebec, Canada H1T 1C8
| | - Émile Levy
- Department of Nutrition, Université de Montréal, Montreal, Quebec, Canada
- CHU Sainte-Justine, Montreal, Quebec, Canada
| | - Jean-Claude Tardif
- Department of Medicine, Université de Montréal, Montreal, Quebec, Canada
- Montreal Heart Institute, Research Center, 5000 Belanger Street, Montreal, Quebec, Canada H1T 1C8
| | - Christine Des Rosiers
- Department of Nutrition, Université de Montréal, Montreal, Quebec, Canada
- Montreal Heart Institute, Research Center, 5000 Belanger Street, Montreal, Quebec, Canada H1T 1C8
| |
Collapse
|
149
|
van der Spuy WJ, Pretorius E. Interaction of red blood cells adjacent to and within a thrombus in experimental cerebral ischaemia. Thromb Res 2013; 132:718-23. [DOI: 10.1016/j.thromres.2013.08.024] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2013] [Revised: 08/05/2013] [Accepted: 08/13/2013] [Indexed: 01/18/2023]
|
150
|
Lipiski M, Deuel JW, Baek JH, Engelsberger WR, Buehler PW, Schaer DJ. Human Hp1-1 and Hp2-2 phenotype-specific haptoglobin therapeutics are both effective in vitro and in guinea pigs to attenuate hemoglobin toxicity. Antioxid Redox Signal 2013; 19:1619-33. [PMID: 23418677 PMCID: PMC3809386 DOI: 10.1089/ars.2012.5089] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
AIMS Infusion of purified haptoglobin (Hp) functions as an effective hemoglobin (Hb) scavenging therapeutic in animal models of hemolysis to prevent cardiovascular and renal injury. Epidemiologic studies demonstrate the phenotype heterogeneity of human Hp proteins and suggest differing vascular protective potential imparted by the dimeric Hp1-1 and the polymeric Hp2-2. RESULTS In vitro experiments and in vivo studies in guinea pigs were performed to evaluate phenotype-specific differences in Hp therapeutics. We found no differences between the two phenotypes in Hb binding and intravascular compartmentalization of Hb in vivo. Both Hp1-1 and Hp2-2 attenuate Hb-induced blood pressure response and renal iron deposition. These findings were consistent with equal prevention of Hb endothelial translocation. The modulation of oxidative Hb reactions by the two Hp phenotypes was not found to be different. Both phenotypes stabilize the ferryl (Fe(4+)) Hb transition state, provide heme retention within the complex, and prevent Hb-driven low-density lipoprotein (LDL) peroxidation. Hb-mediated peroxidation of LDL resulted in endothelial toxicity, which was equally blocked by the addition of Hp1-1 and Hp2-2. INNOVATION AND CONCLUSION The present data do not provide support for the concept that phenotype-specific Hp therapeutics offer differential efficacy in mitigating acute Hb toxicity.
Collapse
Affiliation(s)
- Miriam Lipiski
- 1 Division of Internal Medicine, University of Zurich , Zurich, Switzerland
| | | | | | | | | | | |
Collapse
|