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Navarrete Á, Inostroza M, Utrera A, Bezmalinovic A, González-Candia A, Rivera E, Godoy-Guzmán C, Herrera EA, García-Herrera C. Biomechanical effects of hemin and sildenafil treatments on the aortic wall of chronic-hypoxic lambs. Front Bioeng Biotechnol 2024; 12:1406214. [PMID: 39021365 PMCID: PMC11252865 DOI: 10.3389/fbioe.2024.1406214] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2024] [Accepted: 06/07/2024] [Indexed: 07/20/2024] Open
Abstract
Introduction: Gestation under chronic hypoxia causes pulmonary hypertension, cardiovascular remodeling, and increased aortic stiffness in the offspring. To mitigate the neonatal cardiovascular risk, pharmacological treatments (such as hemin and sildenafil) have been proposed to improve pulmonary vasodilation. However, little is known about the effects of these treatments on the aorta. Therefore, we studied the effect of hemin and sildenafil treatments in the aorta of lambs gestated and raised at highlands, thereby subjected to chronic hypoxia. Methods: Several biomechanical tests were conducted in the descending thoracic aorta (DTA) and the distal abdominal aorta (DAA), assessing 3 groups of study of hypoxic animals: non-treated (Control) and treated either with hemin or sildenafil. Based on them, the stiffness level has been quantified in both zones, along with the physiological strain in the unloaded aortic duct. Furthermore, a morphological study by histology was conducted in the DTA. Results: Biomechanical results indicate that treatments trigger an increment of axial pre-stress and circumferential residual stress levels in DTA and DAA of lambs exposed to high-altitude chronic hypoxia, which reveals a vasodilatation improvement along with an anti-hypertensive response under this characteristic environmental condition. In addition, histological findings do not reveal significant differences in either structure or microstructural content. Discussion: The biomechanics approach emerges as a valuable study perspective, providing insights to explain the physiological mechanisms of vascular function. According to established results, alterations in the function of the aortic wall may not necessarily be explained by morphostructural changes, but rather by the characteristic mechanical state of the microstructural components that are part of the studied tissue. In this sense, the reported biomechanical changes are beneficial in mitigating the adverse effects of hypobaric hypoxia exposure during gestation and early postnatal life.
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Affiliation(s)
- Álvaro Navarrete
- Laboratorio de Biomecánica y Biomateriales, Departamento de Ingeniería Mecánica, Universidad de Santiago de Chile, USACH, Santiago de Chile, Chile
| | - Matías Inostroza
- Laboratorio de Biomecánica y Biomateriales, Departamento de Ingeniería Mecánica, Universidad de Santiago de Chile, USACH, Santiago de Chile, Chile
| | - Andrés Utrera
- Laboratorio de Biomecánica y Biomateriales, Departamento de Ingeniería Mecánica, Universidad de Santiago de Chile, USACH, Santiago de Chile, Chile
| | - Alejandro Bezmalinovic
- Laboratorio de Biomecánica y Biomateriales, Departamento de Ingeniería Mecánica, Universidad de Santiago de Chile, USACH, Santiago de Chile, Chile
| | | | - Eugenio Rivera
- Laboratorio de Biomecánica y Biomateriales, Departamento de Ingeniería Mecánica, Universidad de Santiago de Chile, USACH, Santiago de Chile, Chile
| | - Carlos Godoy-Guzmán
- Laboratorio de Ingeniería de Tejidos, Centro de Investigación Biomédica y Aplicada (CIBAP), Escuela de Medicina, Universidad de Santiago de Chile, Santiago de Chile, Chile
| | - Emilio A. Herrera
- Pathophysiology Program, Institute of Biomedical Sciences (ICBM), Faculty of Medicine, Universidad de Chile, Santiago, Chile
- International Center for Andean Studies (INCAS), Universidad de Chile, Santiago, Chile
| | - Claudio García-Herrera
- Laboratorio de Biomecánica y Biomateriales, Departamento de Ingeniería Mecánica, Universidad de Santiago de Chile, USACH, Santiago de Chile, Chile
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Zhao ML, Lu ZJ, Yang L, Ding S, Gao F, Liu YZ, Yang XL, Li X, He SY. The cardiovascular system at high altitude: A bibliometric and visualization analysis. World J Cardiol 2024; 16:199-214. [PMID: 38690218 PMCID: PMC11056872 DOI: 10.4330/wjc.v16.i4.199] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/22/2023] [Revised: 02/14/2024] [Accepted: 04/01/2024] [Indexed: 04/23/2024] Open
Abstract
BACKGROUND When exposed to high-altitude environments, the cardiovascular system undergoes various changes, the performance and mechanisms of which remain controversial. AIM To summarize the latest research advancements and hot research points in the cardiovascular system at high altitude by conducting a bibliometric and visualization analysis. METHODS The literature was systematically retrieved and filtered using the Web of Science Core Collection of Science Citation Index Expanded. A visualization analysis of the identified publications was conducted employing CiteSpace and VOSviewer. RESULTS A total of 1674 publications were included in the study, with an observed annual increase in the number of publications spanning from 1990 to 2022. The United States of America emerged as the predominant contributor, while Universidad Peruana Cayetano Heredia stood out as the institution with the highest publication output. Notably, Jean-Paul Richalet demonstrated the highest productivity among researchers focusing on the cardiovascular system at high altitude. Furthermore, Peter Bärtsch emerged as the author with the highest number of cited articles. Keyword analysis identified hypoxia, exercise, acclimatization, acute and chronic mountain sickness, pulmonary hypertension, metabolism, and echocardiography as the primary research hot research points and emerging directions in the study of the cardiovascular system at high altitude. CONCLUSION Over the past 32 years, research on the cardiovascular system in high-altitude regions has been steadily increasing. Future research in this field may focus on areas such as hypoxia adaptation, metabolism, and cardiopulmonary exercise. Strengthening interdisciplinary and multi-team collaborations will facilitate further exploration of the pathophysiological mechanisms underlying cardiovascular changes in high-altitude environments and provide a theoretical basis for standardized disease diagnosis and treatment.
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Affiliation(s)
- Mao-Lin Zhao
- Department of Cardiovascular Surgery, The General Hospital of Western Theater Command, College of Medicine, Southwest Jiaotong University, Chengdu 610083, Sichuan Province, China
| | - Zhong-Jie Lu
- Department of Cardiovascular Surgery, The General Hospital of Western Theater Command, College of Medicine, Southwest Jiaotong University, Chengdu 610083, Sichuan Province, China
| | - Li Yang
- Department of Cardiovascular Surgery, The General Hospital of Western Theater Command, College of Medicine, Southwest Jiaotong University, Chengdu 610083, Sichuan Province, China
| | - Sheng Ding
- Department of Cardiovascular Surgery, The General Hospital of Western Theater Command, College of Medicine, Southwest Jiaotong University, Chengdu 610083, Sichuan Province, China
| | - Feng Gao
- Department of Cardiovascular Surgery, The General Hospital of Western Theater Command, College of Medicine, Southwest Jiaotong University, Chengdu 610083, Sichuan Province, China
| | - Yuan-Zhang Liu
- Department of Cardiovascular Surgery, The General Hospital of Western Theater Command, College of Medicine, Southwest Jiaotong University, Chengdu 610083, Sichuan Province, China
| | - Xue-Lin Yang
- Department of Cardiovascular Surgery, The General Hospital of Western Theater Command, College of Medicine, Southwest Jiaotong University, Chengdu 610083, Sichuan Province, China
| | - Xia Li
- Department of Cardiovascular Surgery, The General Hospital of Western Theater Command, College of Medicine, Southwest Jiaotong University, Chengdu 610083, Sichuan Province, China
| | - Si-Yi He
- Department of Cardiovascular Surgery, The General Hospital of Western Theater Command, Chengdu 610083, Sichuan Province, China.
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Kämpf S, Fenk S, Van Cromvoirt A, Bogdanov N, Hartnack S, Stirn M, Hofmann-Lehmann R, Reichler IM, Bogdanova A. Differences in selected blood parameters between brachycephalic and non-brachycephalic dogs. Front Vet Sci 2023; 10:1166032. [PMID: 37649563 PMCID: PMC10464621 DOI: 10.3389/fvets.2023.1166032] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Accepted: 07/11/2023] [Indexed: 09/01/2023] Open
Abstract
Introduction Cranial and upper-airway anatomy of short-nosed, flat-faced brachycephalic dogs predisposes them to brachycephalic obstructive airway syndrome (BOAS). Periodic apnoea increased inspiratory resistance, and an inability to thermoregulate effectively are characteristic of BOAS, but internationally accepted objective markers of BOAS severity are missing. The objective of this study was to compare the selected blood parameters between non-brachycephalic (NC) and brachycephalic (BC) dogs, exploring the possibility of developing a blood test for BOAS severity grading in the future. Methods We evaluated blood biochemistry, complete blood cell counts, red blood cell (RBC) indices, reticulocyte counts, a blood-born marker of intermittent hypoxia (glutathione, NO production), RBC hydration, deformability, and blood markers of metabolic changes and stress between BC (n = 18) and NC (meso- and dolichocephalic, n = 22) dogs. Results Reticulocyte counts and the abundance of middle-fluorescence immature reticulocytes were significantly (p < 0.05) higher in BC dogs compared to NC dogs. BC dogs had significantly more NO-derived NO2 - /NO3 - in plasma than NC dogs. RBCs of BC dogs were shedding significantly more membrane, as follows from the intensity of eosin maleimide staining, and had a significantly higher mean corpuscular hemoglobin concentration than NC dogs. Intracellular reduced glutathione content in RBCs of BC dogs was significantly lower, while plasma lactate was significantly higher in BC dogs compared to NC dogs. Plasma cholesterol and triglycerides were significantly lower, and cortisol was significantly higher in BC dogs compared to NC dogs. Eosinophil counts were significantly lower and the neutrophil-to-lymphocyte ratio was higher in BC dogs compared to NC dogs. Discussion Taken together, our findings suggest that the brachycephalic phenotype in dogs is associated with alterations at the level of blood cells and, systemically, with oxidation and metabolic changes. The parameters identified within this study should be further investigated for their potential as objective indicators for BOAS.
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Affiliation(s)
- Sandra Kämpf
- Red Blood Cell Research Group, Institute of Veterinary Physiology, Faculty of Vetsuisse, University of Zurich, Zürich, Switzerland
- Center for Clinical Studies (ZKS), Vetsuisse Faculty, University of Zurich, Zürich, Switzerland
- Clinic of Reproductive Medicine, Vetsuisse Faculty, University of Zurich, Zürich, Switzerland
| | - Simone Fenk
- Red Blood Cell Research Group, Institute of Veterinary Physiology, Faculty of Vetsuisse, University of Zurich, Zürich, Switzerland
- Center for Clinical Studies (ZKS), Vetsuisse Faculty, University of Zurich, Zürich, Switzerland
| | - Ankie Van Cromvoirt
- Red Blood Cell Research Group, Institute of Veterinary Physiology, Faculty of Vetsuisse, University of Zurich, Zürich, Switzerland
- Center for Clinical Studies (ZKS), Vetsuisse Faculty, University of Zurich, Zürich, Switzerland
| | - Nikolay Bogdanov
- Red Blood Cell Research Group, Institute of Veterinary Physiology, Faculty of Vetsuisse, University of Zurich, Zürich, Switzerland
- Center for Clinical Studies (ZKS), Vetsuisse Faculty, University of Zurich, Zürich, Switzerland
| | - Sonja Hartnack
- Section of Epidemiology, Vetsuisse Faculty, University of Zurich, Zürich, Switzerland
| | - Martina Stirn
- Clinical Laboratory, Department for Clinical Diagnostics and Services, Vetsuisse Faculty, University of Zurich, Zürich, Switzerland
| | - Regina Hofmann-Lehmann
- Center for Clinical Studies (ZKS), Vetsuisse Faculty, University of Zurich, Zürich, Switzerland
- Clinical Laboratory, Department for Clinical Diagnostics and Services, Vetsuisse Faculty, University of Zurich, Zürich, Switzerland
| | - Iris Margaret Reichler
- Clinic of Reproductive Medicine, Vetsuisse Faculty, University of Zurich, Zürich, Switzerland
| | - Anna Bogdanova
- Red Blood Cell Research Group, Institute of Veterinary Physiology, Faculty of Vetsuisse, University of Zurich, Zürich, Switzerland
- Center for Clinical Studies (ZKS), Vetsuisse Faculty, University of Zurich, Zürich, Switzerland
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Mechanism of Hypoxia-Mediated Smooth Muscle Cell Proliferation Leading to Vascular Remodeling. BIOMED RESEARCH INTERNATIONAL 2022; 2022:3959845. [PMID: 36593773 PMCID: PMC9805398 DOI: 10.1155/2022/3959845] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Revised: 11/25/2022] [Accepted: 12/07/2022] [Indexed: 12/25/2022]
Abstract
Vascular remodeling refers to changes in the size, contraction, distribution, and flow rate of blood vessels and even changes in vascular function. Vascular remodeling can cause cardiovascular and cerebrovascular diseases. It can also lead to other systemic diseases, such as pulmonary hypertension, pulmonary atherosclerosis, chronic obstructive pulmonary disease, stroke, and ascites of broilers. Hypoxia is one of the main causes of vascular remodeling. Prolonged hypoxia or intermittent hypoxia can lead to loss of lung ventilation, causing respiratory depression, irregular respiratory rhythms, and central respiratory failure. Animals that are unable to adapt to the highland environment are also prone to sustained constriction of the small pulmonary arteries, increased resistance to pulmonary circulation, and impaired blood circulation, leading to pulmonary hypertension and right heart failure if they live in a highland environment for long periods of time. However, limited studies have been found on the relationship between hypoxia and vascular remodeling. Therefore, this review will explore the relationship between hypoxia and vascular remodeling from the aspects of endoplasmic reticulum stress, mitochondrial dysfunction, abnormal calcium channel, disordered cellular metabolism, abnormal expression of miRNA, and other factors. This will help to understand the detailed mechanism of hypoxia-mediated smooth muscle cell proliferation and vascular remodeling for the better treatment and management of diseases due to vascular remodeling.
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González-Candia A, Candia AA, Paz A, Mobarec F, Urbina-Varela R, del Campo A, Herrera EA, Castillo RL. Cardioprotective Antioxidant and Anti-Inflammatory Mechanisms Induced by Intermittent Hypobaric Hypoxia. Antioxidants (Basel) 2022; 11:antiox11061043. [PMID: 35739940 PMCID: PMC9220055 DOI: 10.3390/antiox11061043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2022] [Revised: 05/05/2022] [Accepted: 05/06/2022] [Indexed: 11/25/2022] Open
Abstract
More than 80 million people live and work (in a chronic or intermittent form) above 2500 masl, and 35 million live in the Andean Mountains. Furthermore, in Chile, it is estimated that 100,000 people work in high-altitude shifts, where stays in the lowlands are interspersed with working visits in the highlands. Acute exposure to high altitude has been shown to induce oxidative stress in healthy human lowlanders due to increased free radical formation and decreased antioxidant capacity. However, intermittent hypoxia (IH) induces preconditioning in animal models, generating cardioprotection. Here, we aim to describe the responses of a cardiac function to four cycles of intermittent hypobaric hypoxia (IHH) in a rat model. The twelve adult Wistar rats were randomly divided into two equal groups, a four-cycle of IHH and a normobaric hypoxic control. Intermittent hypoxia was induced in a hypobaric chamber in four continuous cycles (1 cycle = 4 days of hypoxia + 4 days of normoxia), reaching a barometric pressure equivalent to 4600 m of altitude (428 Torr). At the end of the fourth cycle, cardiac structural and functional variables were also determined by echocardiography; furthermore, cardiac oxidative stress biomarkers (4-Hydroxynonenal, HNE; nitrotyrosine, NT), antioxidant enzymes, and NLRP3 inflammasome panel expression are also determined. Our results show a higher ejection and a shortening fraction of the left ventricle function by the end of the fourth cycle. Furthermore, cardiac tissue presented a decreased expression of antioxidant proteins. However, a decrease in IL-1β, TNF-αn, and oxidative stress markers is observed in IHH compared to normobaric hypoxic controls. Non-significant differences were found in protein levels of NLRP3 and caspase-1. IHH exposure determines structural and functional heart changes. These findings suggest that initial states of IHH are beneficial for cardiovascular function and protection.
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Affiliation(s)
| | - Alejandro A. Candia
- Laboratory of Vascular Function & Reactivity, Pathophysiology Program, ICBM, Faculty of Medicine, Universidad de Chile, Santiago 7500922, Chile; (A.A.C.); (A.P.); (F.M.)
- Department for the Woman and Newborn Health Promotion, Universidad de Chile, Santiago 7500922, Chile
| | - Adolfo Paz
- Laboratory of Vascular Function & Reactivity, Pathophysiology Program, ICBM, Faculty of Medicine, Universidad de Chile, Santiago 7500922, Chile; (A.A.C.); (A.P.); (F.M.)
| | - Fuad Mobarec
- Laboratory of Vascular Function & Reactivity, Pathophysiology Program, ICBM, Faculty of Medicine, Universidad de Chile, Santiago 7500922, Chile; (A.A.C.); (A.P.); (F.M.)
| | - Rodrigo Urbina-Varela
- Laboratorio de Fisiología y Bioenergética Celular, Facultad de Química y de Farmacia, Pontificia Universidad Católica de Chile, Santiago 7820436, Chile; (R.U.-V.); (A.d.C.)
| | - Andrea del Campo
- Laboratorio de Fisiología y Bioenergética Celular, Facultad de Química y de Farmacia, Pontificia Universidad Católica de Chile, Santiago 7820436, Chile; (R.U.-V.); (A.d.C.)
| | - Emilio A. Herrera
- Laboratory of Vascular Function & Reactivity, Pathophysiology Program, ICBM, Faculty of Medicine, Universidad de Chile, Santiago 7500922, Chile; (A.A.C.); (A.P.); (F.M.)
- International Center for Andean Studies (INCAS), University of Chile, Putre 1070000, Chile
- Correspondence: (E.A.H.); or (R.L.C.); Tel.: +56-982-337-566 (R.L.C.)
| | - Rodrigo L. Castillo
- Departamento de Medicina Interna Oriente, Facultad de Medicina, Universidad de Chile, Santiago 7500922, Chile
- Unidad de Paciente Crítico, Hospital del Salvador, Santiago 7500922, Chile
- Correspondence: (E.A.H.); or (R.L.C.); Tel.: +56-982-337-566 (R.L.C.)
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Utrera A, Navarrete Á, González-Candia A, García-Herrera C, Herrera EA. Biomechanical and structural responses of the aorta to intermittent hypobaric hypoxia in a rat model. Sci Rep 2022; 12:3790. [PMID: 35260626 PMCID: PMC8904842 DOI: 10.1038/s41598-022-07616-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Accepted: 02/14/2022] [Indexed: 02/07/2023] Open
Abstract
High altitude hypoxia is a condition experienced by diverse populations worldwide. In addition, several jobs require working shifts where workers are exposed to repetitive cycles of hypobaric hypoxia and normobaric normoxia. Currently, few is known about the biomechanical cardiovascular responses of this condition. In the present study, we investigate the cycle-dependent biomechanical effects of intermittent hypobaric hypoxia (IHH) on the thoracic aorta artery, in terms of both structure and function. To determine the vascular effects of IHH, functional, mechanical and histological approaches were carried out in the thoracic aorta artery, using uniaxial, pre-stretch, ring opening, myography, and histological tests. Three groups of rats were established: control (normobaric normoxia, NN), 4-cycles of intermittent hypoxia (short-term intermittent hypobaric hypoxia, STH), and 10-cycles of intermittent hypoxia (long-term intermittent hypobaric hypoxia, LTH). The pre-stretch and ring opening tests, aimed at quantifying residual strains of the tissues in longitudinal and circumferential directions, showed that the hypoxia condition leads to an increase in the longitudinal stretch and a marked decrease of the circumferential residual strain. The uniaxial mechanical tests were used to determine the elastic properties of the tissues, showing that a general stiffening process occurs during the early stages of the IH (STH group), specially leading to a significative increase in the high strain elastic modulus ([Formula: see text]) and an increasing trend of low strain elastic modulus ([Formula: see text]). In contrast, the LTH group showed a more control-like mechanical behavior. Myography test, used to assess the vasoactive function, revealed that IH induces a high sensitivity to vasoconstrictor agents as a function of hypoxic cycles. In addition, the aorta showed an increased muscle-dependent vasorelaxation on the LTH group. Histological tests, used to quantify the elastic fiber, nuclei, and geometrical properties, showed that the STH group presents a state of vascular fibrosis, with a significant increase in elastin content, and a tendency towards an increase in collagen fibers. In addition, advanced stages of IH (LTH), showed a vascular remodeling effect with a significant increase of internal and external diameters. Considering all the multidimensional vascular effects, we propose the existence of a long-term passive adaptation mechanism and vascular dysfunction as cycle-dependent effects of intermittent exposures to hypobaric hypoxia.
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Affiliation(s)
- Andrés Utrera
- Departamento de Ingeniería Mecánica, Universidad de Santiago de Chile, Santiago, Chile
| | - Álvaro Navarrete
- Departamento de Ingeniería Mecánica, Universidad de Santiago de Chile, Santiago, Chile
| | | | | | - Emilio A Herrera
- Programa de Fisiopatología, ICBM, Facultad de Medicina, Universidad de Chile, Santiago, Chile. .,International Center for Andean Studies (INCAS), Universidad de Chile, Santiago, Chile.
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Candia AA, Arias PV, González-Candia C, Navarrete A, Ebensperger G, Reyes RV, Llanos AJ, González-Candia A, Herrera EA. Melatonin treatment during chronic hypoxic gestation improves neonatal cerebrovascular function. Vascul Pharmacol 2022; 144:106971. [PMID: 35150933 DOI: 10.1016/j.vph.2022.106971] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Revised: 01/13/2022] [Accepted: 02/06/2022] [Indexed: 01/20/2023]
Abstract
BACKGROUND Fetal chronic hypoxia is associated with blood flow redistribution and oxidative damage in the brain, leading to increased perinatal morbimortality. Melatonin reduces oxidative stress, improves vascular function, and has neuroprotective effects. OBJECTIVES This study aimed to determine the effects of an oral melatonin treatment to pregnant ewes at high-altitude, on the cerebrovascular function of their neonates. STUDY DESIGN Ten high-altitude pregnant sheep received either vehicle or melatonin (10 mg/d) during the last third of gestation until delivery. Postnatal daily hemodynamic measurements were recorded from lambs until 12 days old. In addition, lambs were submitted to a graded oxygenation protocol to assess cerebrovascular responses. Subsequently, lambs were euthanized, and middle cerebral arteries (MCA) were collected for vascular function, protein levels, and morphostructural analyses. RESULTS Antenatal treatment doubled plasma levels of melatonin in pregnant ewes. Melatonin increased carotid flow and decreased carotid vascular resistance in the lambs by the end of the first week. Furthermore, melatonin increased MCA's maximal vasoconstrictor and vasodilator responses, associated with nitric oxide-dependent and independent mechanisms. CONCLUSIONS An oral treatment with melatonin during pregnancy promotes postnatal cerebral perfusion in chronically hypoxic neonates. Melatonin is a potential treatment for cerebrovascular dysfunction due to perinatal chronic hypoxia.
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Affiliation(s)
- Alejandro A Candia
- Vascular Function & Reactivity Lab, Pathophysiology Program, ICBM, Faculty of Medicine, Universidad de Chile, Chile; Department for the Woman and Newborn Health Promotion, Universidad de Chile, Santiago, Chile
| | - Pamela V Arias
- Vascular Function & Reactivity Lab, Pathophysiology Program, ICBM, Faculty of Medicine, Universidad de Chile, Chile
| | - Cristopher González-Candia
- Vascular Function & Reactivity Lab, Pathophysiology Program, ICBM, Faculty of Medicine, Universidad de Chile, Chile
| | - Alvaro Navarrete
- Department of Mechanical Engineering, Faculty of Engineering, Universidad de Santiago de, Chile, Chile
| | - Germán Ebensperger
- Pathophysiology Program, ICBM, Faculty of Medicine, Universidad de Chile
| | - Roberto V Reyes
- Pathophysiology Program, ICBM, Faculty of Medicine, Universidad de Chile
| | - Aníbal J Llanos
- Pathophysiology Program, ICBM, Faculty of Medicine, Universidad de Chile; International Center for Andean Studies (INCAS), Universidad de Chile, Chile
| | | | - Emilio A Herrera
- Vascular Function & Reactivity Lab, Pathophysiology Program, ICBM, Faculty of Medicine, Universidad de Chile, Chile; International Center for Andean Studies (INCAS), Universidad de Chile, Chile.
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Castillo-Galán S, Parrau D, Hernández I, Quezada S, Díaz M, Ebensperger G, Herrera EA, Moraga FA, Iturriaga R, Llanos AJ, Reyes RV. The Action of 2-Aminoethyldiphenyl Borinate on the Pulmonary Arterial Hypertension and Remodeling of High-Altitude Hypoxemic Lambs. Front Physiol 2022; 12:765281. [PMID: 35082688 PMCID: PMC8784838 DOI: 10.3389/fphys.2021.765281] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Accepted: 12/07/2021] [Indexed: 01/17/2023] Open
Abstract
Calcium signaling is key for the contraction, differentiation, and proliferation of pulmonary arterial smooth muscle cells. Furthermore, calcium influx through store-operated channels (SOCs) is particularly important in the vasoconstrictor response to hypoxia. Previously, we found a decrease in pulmonary hypertension and remodeling in normoxic newborn lambs partially gestated under chronic hypoxia, when treated with 2-aminoethyldiphenyl borinate (2-APB), a non-specific SOC blocker. However, the effects of 2-APB are unknown in neonates completely gestated, born, and raised under environmental hypoxia. Accordingly, we studied the effects of 2-APB-treatment on the cardiopulmonary variables in lambs under chronic hypobaric hypoxia. Experiments were done in nine newborn lambs gestated, born, and raised in high altitude (3,600 m): five animals were treated with 2-APB [intravenous (i.v.) 10 mg kg–1] for 10 days, while other four animals received vehicle. During the treatment, cardiopulmonary variables were measured daily, and these were also evaluated during an acute episode of superimposed hypoxia, 1 day after the end of the treatment. Furthermore, pulmonary vascular remodeling was assessed by histological analysis 2 days after the end of the treatment. Basal cardiac output and mean systemic arterial pressure (SAP) and resistance from 2-APB- and vehicle-treated lambs did not differ along with the treatment. Mean pulmonary arterial pressure (mPAP) decreased after the first day of 2-APB treatment and remained lower than the vehicle-treated group until the third day, and during the fifth, sixth, and ninth day of treatment. The net mPAP increase in response to acute hypoxia did not change, but the pressure area under the curve (AUC) during hypoxia was slightly lower in 2-APB-treated lambs than in vehicle-treated lambs. Moreover, the 2-APB treatment decreased the pulmonary arterial wall thickness and the α-actin immunoreactivity and increased the luminal area with no changes in the vascular density. Our findings show that 2-APB treatment partially reduced the contractile hypoxic response and reverted the pulmonary vascular remodeling, but this is not enough to normalize the pulmonary hemodynamics in chronically hypoxic newborn lambs.
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Affiliation(s)
- Sebastián Castillo-Galán
- Laboratorio de Neurobiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Daniela Parrau
- Unidad de Fisiología y Fisiopatología Perinatal, Programa de Fisiopatología, Facultad de Medicina, Instituto de Ciencias Biomédicas, Universidad de Chile, Santiago, Chile
| | - Ismael Hernández
- Unidad de Fisiología y Fisiopatología Perinatal, Programa de Fisiopatología, Facultad de Medicina, Instituto de Ciencias Biomédicas, Universidad de Chile, Santiago, Chile
| | - Sebastián Quezada
- School of Health and Biomedical Sciences, RMIT University, Bundoora, VIC, Australia
| | - Marcela Díaz
- Departamento de Promoción de la Salud de la Mujer y el Recién Nacido, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Germán Ebensperger
- Unidad de Fisiología y Fisiopatología Perinatal, Programa de Fisiopatología, Facultad de Medicina, Instituto de Ciencias Biomédicas, Universidad de Chile, Santiago, Chile.,International Center for Andean Studies, Universidad de Chile, Santiago, Chile
| | - Emilio A Herrera
- Unidad de Fisiología y Fisiopatología Perinatal, Programa de Fisiopatología, Facultad de Medicina, Instituto de Ciencias Biomédicas, Universidad de Chile, Santiago, Chile.,International Center for Andean Studies, Universidad de Chile, Santiago, Chile
| | - Fernando A Moraga
- Laboratorio de Fisiología, Hipoxia y Función Vascular, Departamento de Ciencias Biomédicas, Facultad de Medicina, Universidad Católica del Norte, Coquimbo, Chile
| | - Rodrigo Iturriaga
- Laboratorio de Neurobiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile.,Centro de Excelencia en Biomedicina de Magallanes, Universidad de Magallanes, Punta Arenas, Chile
| | - Aníbal J Llanos
- Unidad de Fisiología y Fisiopatología Perinatal, Programa de Fisiopatología, Facultad de Medicina, Instituto de Ciencias Biomédicas, Universidad de Chile, Santiago, Chile.,International Center for Andean Studies, Universidad de Chile, Santiago, Chile
| | - Roberto V Reyes
- Unidad de Fisiología y Fisiopatología Perinatal, Programa de Fisiopatología, Facultad de Medicina, Instituto de Ciencias Biomédicas, Universidad de Chile, Santiago, Chile.,International Center for Andean Studies, Universidad de Chile, Santiago, Chile
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9
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Gonzalez-Candia A, Herrera EA. High Altitude Pregnancies and Vascular Dysfunction: Observations From Latin American Studies. Front Physiol 2021; 12:786038. [PMID: 34950057 PMCID: PMC8688922 DOI: 10.3389/fphys.2021.786038] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Accepted: 11/02/2021] [Indexed: 12/14/2022] Open
Abstract
An estimated human population of 170 million inhabit at high-altitude (HA, above 2,500 m). The potential pathological effects of HA hypobaric hypoxia during gestation have been the focus of several researchers around the world. The studies based on the Himalayan and Central/South American mountains are particularly interesting as these areas account for nearly 70% of the HA world population. At present, studies in human and animal models revealed important alterations in fetal development and growth at HA. Moreover, vascular responses to chronic hypobaria in the pregnant mother and her fetus may induce marked cardiovascular impairments during pregnancy or in the neonatal period. In addition, recent studies have shown potential long-lasting postnatal effects that may increase cardiovascular risk in individuals gestated under chronic hypobaria. Hence, the maternal and fetal adaptive responses to hypoxia, influenced by HA ancestry, are vital for a better developmental and cardiovascular outcome of the offspring. This mini-review exposes and discusses the main determinants of vascular dysfunction due to developmental hypoxia at HA, such as the Andean Mountains, at the maternal and fetal/neonatal levels. Although significant advances have been made from Latin American studies, this area still needs further investigations to reveal the mechanisms involved in vascular dysfunction, to estimate complications of pregnancy and postnatal life adequately, and most importantly, to determine potential treatments to prevent or treat the pathological effects of being developed under chronic hypobaric hypoxia.
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Affiliation(s)
- Alejandro Gonzalez-Candia
- Laboratorio de Función y Reactividad Vascular, Programa de Fisiopatología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile.,Instituto de Ciencias de la Salud, Universidad de O'Higgins, Rancagua, Chile
| | - Emilio A Herrera
- Laboratorio de Función y Reactividad Vascular, Programa de Fisiopatología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile.,International Center for Andean Studies (INCAS), Universidad de Chile, Santiago, Chile
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10
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Gonzaléz-Candia A, Arias PV, Aguilar SA, Figueroa EG, Reyes RV, Ebensperger G, Llanos AJ, Herrera EA. Melatonin Reduces Oxidative Stress in the Right Ventricle of Newborn Sheep Gestated under Chronic Hypoxia. Antioxidants (Basel) 2021; 10:antiox10111658. [PMID: 34829529 PMCID: PMC8614843 DOI: 10.3390/antiox10111658] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Revised: 06/21/2021] [Accepted: 06/23/2021] [Indexed: 02/07/2023] Open
Abstract
Pulmonary arterial hypertension of newborns (PAHN) constitutes a critical condition involving both severe cardiac remodeling and right ventricle dysfunction. One main cause of this condition is perinatal hypoxia and oxidative stress. Thus, it is a public health concern for populations living above 2500 m and in cases of intrauterine chronic hypoxia in lowlands. Still, pulmonary and cardiac impairments in PAHN lack effective treatments. Previously we have shown the beneficial effects of neonatal melatonin treatment on pulmonary circulation. However, the cardiac effects of this treatment are unknown. In this study, we assessed whether melatonin improves cardiac function and modulates right ventricle (RV) oxidative stress. Ten lambs were gestated, born, and raised at 3600 m. Lambs were divided in two groups. One received daily vehicle as control, and another received daily melatonin (1 mg·kg-1·d-1) for 21 days. Daily cardiovascular measurements were recorded and, at 29 days old, cardiac tissue was collected. Melatonin decreased pulmonary arterial pressure at the end of the experimental period. In addition, melatonin enhanced manganese superoxide dismutase and catalase (CAT) expression, while increasing CAT activity in RV. This was associated with a decrease in superoxide anion generation at the mitochondria and NADPH oxidases in RV. Finally, these effects were associated with a marked decrease of oxidative stress markers in RV. These findings support the cardioprotective effects of an oral administration of melatonin in newborns that suffer from developmental chronic hypoxia.
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Affiliation(s)
- Alejandro Gonzaléz-Candia
- Laboratory of Vascular Function and Reactivity, Pathophysiology Program, ICBM, Faculty of Medicine, Universidad de Chile, Av. Salvador 486, Santiago 7500922, Chile; (A.G.-C.); (P.V.A.); (S.A.A.); (E.G.F.)
- Institute of Health Sciences, University of O’Higgins, Libertador Bernardo O’Higgins 611, Rancagua 2820000, Chile
| | - Pamela V. Arias
- Laboratory of Vascular Function and Reactivity, Pathophysiology Program, ICBM, Faculty of Medicine, Universidad de Chile, Av. Salvador 486, Santiago 7500922, Chile; (A.G.-C.); (P.V.A.); (S.A.A.); (E.G.F.)
| | - Simón A. Aguilar
- Laboratory of Vascular Function and Reactivity, Pathophysiology Program, ICBM, Faculty of Medicine, Universidad de Chile, Av. Salvador 486, Santiago 7500922, Chile; (A.G.-C.); (P.V.A.); (S.A.A.); (E.G.F.)
| | - Esteban G. Figueroa
- Laboratory of Vascular Function and Reactivity, Pathophysiology Program, ICBM, Faculty of Medicine, Universidad de Chile, Av. Salvador 486, Santiago 7500922, Chile; (A.G.-C.); (P.V.A.); (S.A.A.); (E.G.F.)
| | - Roberto V. Reyes
- Pathophysiology Program, ICBM, Faculty of Medicine, Universidad de Chile, Av. Salvador 486, Santiago 7500922, Chile; (R.V.R.); (G.E.); (A.J.L.)
| | - Germán Ebensperger
- Pathophysiology Program, ICBM, Faculty of Medicine, Universidad de Chile, Av. Salvador 486, Santiago 7500922, Chile; (R.V.R.); (G.E.); (A.J.L.)
| | - Aníbal J. Llanos
- Pathophysiology Program, ICBM, Faculty of Medicine, Universidad de Chile, Av. Salvador 486, Santiago 7500922, Chile; (R.V.R.); (G.E.); (A.J.L.)
- International Center for Andean Studies (INCAS), Universidad de Chile, Baquedano s/n, Putre 1070000, Chile
| | - Emilio A. Herrera
- Laboratory of Vascular Function and Reactivity, Pathophysiology Program, ICBM, Faculty of Medicine, Universidad de Chile, Av. Salvador 486, Santiago 7500922, Chile; (A.G.-C.); (P.V.A.); (S.A.A.); (E.G.F.)
- International Center for Andean Studies (INCAS), Universidad de Chile, Baquedano s/n, Putre 1070000, Chile
- Correspondence: ; Tel.: +56-2-2977-0543
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11
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Herrera EA, González-Candia A. Gestational Hypoxia and Blood-Brain Barrier Permeability: Early Origins of Cerebrovascular Dysfunction Induced by Epigenetic Mechanisms. Front Physiol 2021; 12:717550. [PMID: 34489733 PMCID: PMC8418233 DOI: 10.3389/fphys.2021.717550] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Accepted: 07/19/2021] [Indexed: 01/25/2023] Open
Abstract
Fetal chronic hypoxia leads to intrauterine growth restriction (IUGR), which is likely to reduce oxygen delivery to the brain and induce long-term neurological impairments. These indicate a modulatory role for oxygen in cerebrovascular development. During intrauterine hypoxia, the fetal circulation suffers marked adaptations in the fetal cardiac output to maintain oxygen and nutrient delivery to vital organs, known as the "brain-sparing phenotype." This is a well-characterized response; however, little is known about the postnatal course and outcomes of this fetal cerebrovascular adaptation. In addition, several neurodevelopmental disorders have their origins during gestation. Still, few studies have focused on how intrauterine fetal hypoxia modulates the normal brain development of the blood-brain barrier (BBB) in the IUGR neonate. The BBB is a cellular structure formed by the neurovascular unit (NVU) and is organized by a monolayer of endothelial and mural cells. The BBB regulates the entry of plasma cells and molecules from the systemic circulation to the brain. A highly selective permeability system achieves this through integral membrane proteins in brain endothelial cells. BBB breakdown and dysfunction in cerebrovascular diseases lead to leakage of blood components into the brain parenchyma, contributing to neurological deficits. The fetal brain circulation is particularly susceptible in IUGR and is proposed to be one of the main pathological processes deriving BBB disruption. In the last decade, several epigenetic mechanisms activated by IU hypoxia have been proposed to regulate the postnatal BBB permeability. However, few mechanistic studies about this topic are available, and little evidence shows controversy. Therefore, in this mini-review, we analyze the BBB permeability-associated epigenetic mechanisms in the brain exposed to chronic intrauterine hypoxia.
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Affiliation(s)
- Emilio A Herrera
- Laboratory of Vascular Function and Reactivity, Pathophysiology Program, ICBM, Faculty of Medicine, University of Chile, Santiago, Chile
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12
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Siques P, Pena E, Brito J, El Alam S. Oxidative Stress, Kinase Activation, and Inflammatory Pathways Involved in Effects on Smooth Muscle Cells During Pulmonary Artery Hypertension Under Hypobaric Hypoxia Exposure. Front Physiol 2021; 12:690341. [PMID: 34434114 PMCID: PMC8381601 DOI: 10.3389/fphys.2021.690341] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Accepted: 07/16/2021] [Indexed: 12/23/2022] Open
Abstract
High-altitude exposure results in hypobaric hypoxia, which affects organisms by activating several mechanisms at the physiological, cellular, and molecular levels and triggering the development of several pathologies. One such pathology is high-altitude pulmonary hypertension (HAPH), which is initiated through hypoxic pulmonary vasoconstriction to distribute blood to more adequately ventilated areas of the lungs. Importantly, all layers of the pulmonary artery (adventitia, smooth muscle, and endothelium) contribute to or are involved in the development of HAPH. However, the principal action sites of HAPH are pulmonary artery smooth muscle cells (PASMCs), which interact with several extracellular and intracellular molecules and participate in mechanisms leading to proliferation, apoptosis, and fibrosis. This review summarizes the alterations in molecular pathways related to oxidative stress, inflammation, kinase activation, and other processes that occur in PASMCs during pulmonary hypertension under hypobaric hypoxia and proposes updates to pharmacological treatments to mitigate the pathological changes in PASMCs under such conditions. In general, PASMCs exposed to hypobaric hypoxia undergo oxidative stress mediated by Nox4, inflammation mediated by increases in interleukin-6 levels and inflammatory cell infiltration, and activation of the protein kinase ERK1/2, which lead to the proliferation of PASMCs and contribute to the development of hypobaric hypoxia-induced pulmonary hypertension.
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Affiliation(s)
- Patricia Siques
- Institute of Health Studies, Arturo Prat University, Iquique, Chile
| | - Eduardo Pena
- Institute of Health Studies, Arturo Prat University, Iquique, Chile
| | - Julio Brito
- Institute of Health Studies, Arturo Prat University, Iquique, Chile
| | - Samia El Alam
- Institute of Health Studies, Arturo Prat University, Iquique, Chile
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13
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Rivera E, Canales C, Pacheco M, García-Herrera C, Macías D, Celentano DJ, Herrera EA. Biomechanical characterization of the passive response of the thoracic aorta in chronic hypoxic newborn lambs using an evolutionary strategy. Sci Rep 2021; 11:13875. [PMID: 34230509 PMCID: PMC8260639 DOI: 10.1038/s41598-021-93267-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Accepted: 06/22/2021] [Indexed: 11/22/2022] Open
Abstract
The present study involves experiments and modelling aimed at characterizing the passive structural mechanical behavior of the chronic hypoxic lamb thoracic aorta, whose gestation, birth and postnatal period were carried at high altitude (3600 masl). To this end, the mechanical response was studied via tensile and pressurization tests. The tensile and pressurization tests measurements were used simultaneously to calibrate the material parameters of the Gasser-Holzapfel-Ogden (GHO) hyperelasctic anisotropic constitutive model through an analytical-numerical optimization procedure solved with an evolutionary strategy that guarantees a stable response of the model. The model and procedure of calibration adequately adjust to the material behavior in a wide deformation range with an appropriate physical description. The results of this study predict the mechanical response of the lamb thoracic aorta under generalized loading states like those that can occur in physiological conditions and/or in systemic arterial hypertension. Finally, the novel use of the evolutionary strategy, together with the set of experiments and tools used in this study, provide a robust alternative to validate biomechanical characterizations.
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Affiliation(s)
- Eugenio Rivera
- Departamento de Ingeniería Mecánica, Universidad de Santiago de Chile (USACH), Av. Bernardo O'Higgins 3363, Santiago de Chile, Chile.
| | - Claudio Canales
- Departamento de Ingeniería Mecánica, Universidad de Santiago de Chile (USACH), Av. Bernardo O'Higgins 3363, Santiago de Chile, Chile
| | - Matías Pacheco
- Departamento de Ingeniería Mecánica, Universidad de Santiago de Chile (USACH), Av. Bernardo O'Higgins 3363, Santiago de Chile, Chile
| | - Claudio García-Herrera
- Departamento de Ingeniería Mecánica, Universidad de Santiago de Chile (USACH), Av. Bernardo O'Higgins 3363, Santiago de Chile, Chile
| | - Demetrio Macías
- ICD, P2MN, L2n, Université de Technologie de Troyes, ERL 7004, CNRS, Troyes, France
| | - Diego J Celentano
- Departamento de Ingeniería Mecánica y Metalúrgica, Pontificia Universidad Católica de Chile, Av. Vicuña Mackenna 4860, Santiago de Chile, Chile
| | - Emilio A Herrera
- Laboratorio de Función y Reactividad Vascular, Programa de Fisiopatología, ICBM, Universidad de Chile, Av. Salvador 486, Santiago de Chile, Chile
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14
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Figueroa EG, Gonzaléz-Candia A, Villanueva CA, Ebensperger G, Reyes RV, Llanos AJ, Herrera EA. Beneficial effects of melatonin on prostanoids pathways in pulmonary hypertensive neonates. Vascul Pharmacol 2021; 138:106853. [PMID: 33766627 DOI: 10.1016/j.vph.2021.106853] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Revised: 03/03/2021] [Accepted: 03/08/2021] [Indexed: 01/04/2023]
Abstract
Pulmonary arterial hypertension of the newborn (PAHN) is a syndrome caused by chronic hypoxia, characterized by decreased vasodilator function, a marked vasoconstrictor activity, proliferation of smooth muscle cells (SMC) and thickening of the extracellular matrix in the pulmonary circulation, among other characteristics. Prostaglandins are derived from the arachidonic acid (AA) metabolism and are important regulators of pulmonary vascular tone. Since hypoxia induces oxidative stress and has been related to PAHN, a postnatal treatment with melatonin has been proposed due to its antioxidant properties. Here, we determined the effects of melatonin on pulmonary vascular homeostasis given by prostanoids. Ten PAHN newborn lambs were divided in two groups and treated either with vehicle or melatonin. After 1 week of treatment, we assessed pulmonary vascular prostanoids function and expression by wire myography, RT-PCR, Western Blot and immunohistochemistry. Melatonin improved in vivo and ex vivo pulmonary vasodilation. This was associated with an increased function and expression of vasodilator prostanoids at the expense of vasoconstrictor prostanoids. Our study demonstrates for the first time that melatonin may enhance the vasodilator prostanoid pathway in PAHN.
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Affiliation(s)
- Esteban G Figueroa
- Laboratory of Vascular Function & Reactivity, Pathophysiology Program, ICBM, Faculty of Medicine, Universidad de Chile, Chile
| | - Alejandro Gonzaléz-Candia
- Laboratory of Vascular Function & Reactivity, Pathophysiology Program, ICBM, Faculty of Medicine, Universidad de Chile, Chile; Institute of Health Sciences, University of O'Higgins, Rancagua, Chile
| | - Cristian A Villanueva
- Laboratory of Vascular Function & Reactivity, Pathophysiology Program, ICBM, Faculty of Medicine, Universidad de Chile, Chile
| | - Germán Ebensperger
- Pathophysiology Program, ICBM, Faculty of Medicine, Universidad de Chile, Chile
| | - Roberto V Reyes
- Pathophysiology Program, ICBM, Faculty of Medicine, Universidad de Chile, Chile
| | - Aníbal J Llanos
- Pathophysiology Program, ICBM, Faculty of Medicine, Universidad de Chile, Chile; International Center for Andean Studies (INCAS), Universidad de Chile, Chile
| | - Emilio A Herrera
- Laboratory of Vascular Function & Reactivity, Pathophysiology Program, ICBM, Faculty of Medicine, Universidad de Chile, Chile; Pathophysiology Program, ICBM, Faculty of Medicine, Universidad de Chile, Chile; International Center for Andean Studies (INCAS), Universidad de Chile, Chile.
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15
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Navarrete A, Chen Z, Aranda P, Poblete D, Utrera A, García-Herrera CM, Gonzalez-Candia A, Beñaldo FA, Ebensperger G, Reyes RV, Herrera EA, Llanos AJ. Study of the Effect of Treatment With Atrial Natriuretic Peptide (ANP) and Cinaciguat in Chronic Hypoxic Neonatal Lambs on Residual Strain and Microstructure of the Arteries. Front Bioeng Biotechnol 2020; 8:590488. [PMID: 33244466 PMCID: PMC7683788 DOI: 10.3389/fbioe.2020.590488] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2020] [Accepted: 10/21/2020] [Indexed: 01/01/2023] Open
Abstract
In this study, we assessed the effects of Atrial Natriuretic Peptide (ANP) and Cinaciguat, as experimental medicines to treat neonatal lambs exposed to chronic hypoxic conditions. To compare the different treatments, the mechanical responses of aorta, carotid, and femoral arterial walls were analyzed by means of axial pre-stretch and ring-opening tests, through a study with n = 6 animals for each group analyzed. The axial pre-stretch test measures the level of shortening in different zones of the arteries when extracted from lambs, while the ring-opening test is used to quantify the degree of residual circumferential deformation in a given zone of an artery. In addition, histological studies were carried out to measure elastin, collagen, and smooth muscle cell (SMC) nuclei densities, both in control and treated groups. The results show that mechanical response is related with histological results, specifically in the proximal abdominal aorta (PAA) and distal carotid zones (DCA), where the cell nuclei content is related to a decrease of residual deformations. The opening angle and the elastic fibers of the aorta artery were statistically correlated (p < 0.05). Specifically, in PAA zone, there are significant differences of opening angle and cell nuclei density values between control and treated groups (p-values to opening angle: Control-ANP = 2 ⋅ 10-2, Control-Cinaciguat = 1 ⋅ 10-2; p-values to cell nuclei density: Control-ANP = 5 ⋅ 10-4, Control-Cinaciguat = 2 ⋅ 10-2). Respect to distal carotid zone (DCA), significant differences between Control and Cinaciguat groups were observed to opening angle (p-value = 4 ⋅ 10-2), and cell nuclei density (p-value = 1 ⋅ 10-2). Our findings add evidence that medical treatments may have effects on the mechanical responses of arterial walls and should be taken into account when evaluating the complete medical outcome.
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Affiliation(s)
- Alvaro Navarrete
- Departamento de Ingeniería Mecánica, Universidad de Santiago de Chile, Santiago, Chile
| | - Zhuoming Chen
- Departamento de Ingeniería Mecánica, Universidad de Santiago de Chile, Santiago, Chile
| | - Pedro Aranda
- Departamento de Ingeniería Mecánica, Universidad de Santiago de Chile, Santiago, Chile
| | - Daniel Poblete
- Departamento de Ingeniería Mecánica, Universidad de Santiago de Chile, Santiago, Chile
| | - Andrés Utrera
- Departamento de Ingeniería Mecánica, Universidad de Santiago de Chile, Santiago, Chile
| | | | - Alejandro Gonzalez-Candia
- Instituto de Ciencias de la Salud, Universidad de O’Higgins, Rancagua, Chile
- Pathophysiology Program, Faculty of Medicine, Institute of Biomedical Sciences (ICBM), Universidad de Chile, Santiago, Chile
| | - Felipe A. Beñaldo
- Pathophysiology Program, Faculty of Medicine, Institute of Biomedical Sciences (ICBM), Universidad de Chile, Santiago, Chile
| | - German Ebensperger
- Pathophysiology Program, Faculty of Medicine, Institute of Biomedical Sciences (ICBM), Universidad de Chile, Santiago, Chile
| | - Roberto V. Reyes
- Pathophysiology Program, Faculty of Medicine, Institute of Biomedical Sciences (ICBM), Universidad de Chile, Santiago, Chile
- International Center for Andean Studies (INCAS), Universidad de Chile, Santiago, Chile
| | - Emilio A. Herrera
- Pathophysiology Program, Faculty of Medicine, Institute of Biomedical Sciences (ICBM), Universidad de Chile, Santiago, Chile
- International Center for Andean Studies (INCAS), Universidad de Chile, Santiago, Chile
| | - Anibal J. Llanos
- Pathophysiology Program, Faculty of Medicine, Institute of Biomedical Sciences (ICBM), Universidad de Chile, Santiago, Chile
- International Center for Andean Studies (INCAS), Universidad de Chile, Santiago, Chile
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16
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Rivera E, García-Herrera C, González-Candia A, Celentano DJ, Herrera EA. Effects of melatonin on the passive mechanical response of arteries in chronic hypoxic newborn lambs. J Mech Behav Biomed Mater 2020; 112:104013. [PMID: 32846285 DOI: 10.1016/j.jmbbm.2020.104013] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2020] [Revised: 04/15/2020] [Accepted: 07/26/2020] [Indexed: 02/07/2023]
Abstract
Chronic hypoxia is a condition that increases the cardiovascular complications of newborns gestated and born at high altitude (HA), over 2500 m above sea level (masl). A particularly complex pathology is pulmonary arterial hypertension of the neonate (PHN), which is increased at HA due to hypobaric hypoxia. Basic and clinical research have recognized that new treatments are needed, because current ones are, in general, palliative and with low effectiveness. Therefore, recently we have proposed melatonin as a potential adjuvant treatment to improve cardiopulmonary function. However, melatonin effects on the mechanical response of the arteries and their microstructure are not known. This study assesses the effects of a neonatal treatment with daily low doses of melatonin on the passive biomechanical behavior of the aorta artery and main pulmonary artery of PHN lambs born in chronic hypobaric hypoxia (at 3600 masl). With this purpose, ex-vivo measurements were made on axial stretch, tensile and opening ring tests together with a histological analysis to explore the morphometry and microstructure of the arteries. Our results show that the passive mechanical properties of the aorta artery and main pulmonary artery of lambs do not seem to be affected by a treatment based on low melatonin doses. However, we found evidence that melatonin has microstructural effects, particularly, diminishing cell proliferation, which is an indicator of antiremodeling capacity. Therefore, the use of melatonin as an adjuvant against pathologies like PHN would present antiproliferative effect at the microstructural level, keeping the macroscopic properties of the aorta artery and main pulmonary artery.
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Affiliation(s)
- Eugenio Rivera
- Departamento de Ingeniería Mecánica, Universidad de Santiago de Chile, Av. Bernardo O'Higgins, 3363, Santiago de Chile, Chile
| | - Claudio García-Herrera
- Departamento de Ingeniería Mecánica, Universidad de Santiago de Chile, Av. Bernardo O'Higgins, 3363, Santiago de Chile, Chile.
| | - Alejandro González-Candia
- International Center for Andean Studies (INCAS), Universidad de Chile, Baquedano S/n, Putre, Chile; Institute of Health Sciences, University of O'Higgins, Libertador Bernardo O'Higgins 611, Rancagua, Chile
| | - Diego J Celentano
- Departamento de Ingeniería Mecánica y Metalúrgica, Pontificia Universidad Católica de Chile, Av. Vicuña Mackenna 4860, Santiago de Chile, Chile
| | - Emilio A Herrera
- Laboratorio de Función y Reactividad Vascular, Programa de Fisiopatología, ICBM, Universidad de Chile, Av. Salvador 486, Santiago de Chile, Chile; International Center for Andean Studies (INCAS), Universidad de Chile, Baquedano S/n, Putre, Chile
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17
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Gonzalez-Candia A, Veliz M, Carrasco-Pozo C, Castillo RL, Cárdenas JC, Ebensperger G, Reyes RV, Llanos AJ, Herrera EA. Antenatal melatonin modulates an enhanced antioxidant/pro-oxidant ratio in pulmonary hypertensive newborn sheep. Redox Biol 2019; 22:101128. [PMID: 30771751 PMCID: PMC6375064 DOI: 10.1016/j.redox.2019.101128] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2018] [Revised: 01/27/2019] [Accepted: 01/28/2019] [Indexed: 01/07/2023] Open
Abstract
Chronic hypobaric hypoxia during fetal and neonatal life induces neonatal pulmonary hypertension. Hypoxia and oxidative stress are driving this condition, which implies an increase generation of reactive oxygen species (ROS) and/or decreased antioxidant capacity. Melatonin has antioxidant properties that decrease oxidative stress and improves pulmonary vascular function when administered postnatally. However, the effects of an antenatal treatment with melatonin in the neonatal pulmonary function and oxidative status are unknown. Therefore, we hypothesized that an antenatal therapy with melatonin improves the pulmonary arterial pressure and antioxidant status in high altitude pulmonary hypertensive neonates. Twelve ewes were bred at high altitude (3600 m); 6 of them were used as a control group (vehicle 1.4% ethanol) and 6 as a melatonin treated group (10 mg d-1 melatonin in vehicle). Treatments were given once daily during the last third of gestation (100-150 days). Lambs were born and raised with their mothers until 12 days old, and neonatal pulmonary arterial pressure and resistance, plasma antioxidant capacity and the lung oxidative status were determined. Furthermore, we measured the pulmonary expression and activity for the antioxidant enzymes superoxide dismutase, catalase and glutathione peroxidase, and the oxidative stress markers 8-isoprostanes, 4HNE and nitrotyrosine. Finally, we assessed pulmonary pro-oxidant sources by the expression and function of NADPH oxidase, mitochondria and xanthine oxidase. Melatonin decreased the birth weight. However, melatonin enhanced the plasma antioxidant capacity and decreased the pulmonary antioxidant activity, associated with a diminished oxidative stress during postnatal life. Interestingly, melatonin also decreased ROS generation at the main pro-oxidant sources. Our findings suggest that antenatal administration of melatonin programs an enhanced antioxidant/pro-oxidant status, modulating ROS sources in the postnatal lung.
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Affiliation(s)
- Alejandro Gonzalez-Candia
- Programa de Fisiopatología, Instituto de Ciencias Biomédicas (ICBM), Facultad de Medicina, Universidad de Chile, Av. Salvador 486, Providencia 7500922, Santiago, Chile
| | - Marcelino Veliz
- Programa de Fisiopatología, Instituto de Ciencias Biomédicas (ICBM), Facultad de Medicina, Universidad de Chile, Av. Salvador 486, Providencia 7500922, Santiago, Chile
| | - Catalina Carrasco-Pozo
- Departamento de Nutrición, Facultad de Medicina, Universidad de Chile, Av. Independencia 1027, Independencia, Santiago, Chile
| | - Rodrigo L Castillo
- Programa de Fisiopatología, Instituto de Ciencias Biomédicas (ICBM), Facultad de Medicina, Universidad de Chile, Av. Salvador 486, Providencia 7500922, Santiago, Chile; Departamento de Medicina Interna Oriente, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - J Cesar Cárdenas
- Programa de Anatomía y Biología del Desarrollo, Instituto de Ciencias Biomédicas (ICBM), Facultad de Medicina, Universidad de Chile, Santiago, Chile; Geroscience Center for Brain Health and Metabolism, Santiago, Chile
| | - Germán Ebensperger
- Programa de Fisiopatología, Instituto de Ciencias Biomédicas (ICBM), Facultad de Medicina, Universidad de Chile, Av. Salvador 486, Providencia 7500922, Santiago, Chile
| | - Roberto V Reyes
- Programa de Fisiopatología, Instituto de Ciencias Biomédicas (ICBM), Facultad de Medicina, Universidad de Chile, Av. Salvador 486, Providencia 7500922, Santiago, Chile
| | - Aníbal J Llanos
- Programa de Fisiopatología, Instituto de Ciencias Biomédicas (ICBM), Facultad de Medicina, Universidad de Chile, Av. Salvador 486, Providencia 7500922, Santiago, Chile; International Center for Andean Studies (INCAS), Universidad de Chile, Baquedano s/n, Putre, Chile
| | - Emilio A Herrera
- Programa de Fisiopatología, Instituto de Ciencias Biomédicas (ICBM), Facultad de Medicina, Universidad de Chile, Av. Salvador 486, Providencia 7500922, Santiago, Chile; International Center for Andean Studies (INCAS), Universidad de Chile, Baquedano s/n, Putre, Chile.
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18
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Reyes RV, Castillo-Galán S, Hernandez I, Herrera EA, Ebensperger G, Llanos AJ. Revisiting the Role of TRP, Orai, and ASIC Channels in the Pulmonary Arterial Response to Hypoxia. Front Physiol 2018; 9:486. [PMID: 29867539 PMCID: PMC5949889 DOI: 10.3389/fphys.2018.00486] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Accepted: 04/16/2018] [Indexed: 12/11/2022] Open
Abstract
The pulmonary arteries are exquisitely responsive to oxygen changes. They rapidly and proportionally contract as arterial PO2 decrease, and they relax as arterial PO2 is re-established. The hypoxic pulmonary vasoconstriction (HPV) is intrinsic since it does not require neural or endocrine factors, as evidenced in isolated vessels. On the other hand, pulmonary arteries also respond to sustained hypoxia with structural and functional remodeling, involving growth of smooth muscle medial layer and later recruitment of adventitial fibroblasts, secreted mitogens from endothelium and changes in the response to vasoconstrictor and vasodilator stimuli. Hypoxic pulmonary arterial vasoconstriction and remodeling are relevant biological responses both under physiological and pathological conditions, to explain matching between ventilation and perfusion, fetal to neonatal transition of pulmonary circulation and pulmonary artery over-constriction and thickening in pulmonary hypertension. Store operated channels (SOC) and receptor operated channels (ROC) are plasma membrane cationic channels that mediate calcium influx in response to depletion of internal calcium stores or receptor activation, respectively. They are involved in both HPV and pathological remodeling since their pharmacological blockade or genetic suppression of several of the Stim, Orai, TRP, or ASIC proteins in SOC or ROC complexes attenuate the calcium increase, the tension development, the pulmonary artery smooth muscle proliferation, and pulmonary arterial hypertension. In this Mini Review, we discussed the evidence obtained in in vivo animal models, at the level of isolated organ or cells of pulmonary arteries, and we identified and discussed the questions for future research needed to validate these signaling complexes as targets against pulmonary hypertension.
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Affiliation(s)
- Roberto V Reyes
- Unidad de Fisiología y Fisiopatología Perinatal, Programa de Fisiopatología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile.,International Center for Andean Studies, Universidad de Chile, Santiago, Chile
| | - Sebastián Castillo-Galán
- Unidad de Fisiología y Fisiopatología Perinatal, Programa de Fisiopatología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Ismael Hernandez
- Unidad de Fisiología y Fisiopatología Perinatal, Programa de Fisiopatología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Emilio A Herrera
- Unidad de Fisiología y Fisiopatología Perinatal, Programa de Fisiopatología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile.,International Center for Andean Studies, Universidad de Chile, Santiago, Chile
| | - Germán Ebensperger
- Unidad de Fisiología y Fisiopatología Perinatal, Programa de Fisiopatología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile.,International Center for Andean Studies, Universidad de Chile, Santiago, Chile
| | - Aníbal J Llanos
- Unidad de Fisiología y Fisiopatología Perinatal, Programa de Fisiopatología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile.,International Center for Andean Studies, Universidad de Chile, Santiago, Chile
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19
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Astorga CR, González-Candia A, Candia AA, Figueroa EG, Cañas D, Ebensperger G, Reyes RV, Llanos AJ, Herrera EA. Melatonin Decreases Pulmonary Vascular Remodeling and Oxygen Sensitivity in Pulmonary Hypertensive Newborn Lambs. Front Physiol 2018; 9:185. [PMID: 29559926 PMCID: PMC5845624 DOI: 10.3389/fphys.2018.00185] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2018] [Accepted: 02/20/2018] [Indexed: 12/16/2022] Open
Abstract
Background: Chronic hypoxia and oxidative stress during gestation lead to pulmonary hypertension of the neonate (PHN), a condition characterized by abnormal pulmonary arterial reactivity and remodeling. Melatonin has strong antioxidant properties and improves pulmonary vascular function. Here, we aimed to study the effects of melatonin on the function and structure of pulmonary arteries from PHN lambs. Methods: Twelve lambs (Ovis aries) gestated and born at highlands (3,600 m) were instrumented with systemic and pulmonary catheters. Six of them were assigned to the control group (CN, oral vehicle) and 6 were treated with melatonin (MN, 1 mg.kg−1.d−1) during 10 days. At the end of treatment, we performed a graded oxygenation protocol to assess cardiopulmonary responses to inspired oxygen variations. Further, we obtained lung and pulmonary trunk samples for histology, molecular biology, and immunohistochemistry determinations. Results: Melatonin reduced the in vivo pulmonary pressor response to oxygenation changes. In addition, melatonin decreased cellular density of the media and diminished the proliferation marker KI67 in resistance vessels and pulmonary trunk (p < 0.05). This was associated with a decreased in the remodeling markers α-actin (CN 1.28 ± 0.18 vs. MN 0.77 ± 0.04, p < 0.05) and smoothelin-B (CN 2.13 ± 0.31 vs. MN 0.88 ± 0.27, p < 0.05). Further, melatonin increased vascular density by 134% and vascular luminal surface by 173% (p < 0.05). Finally, melatonin decreased nitrotyrosine, an oxidative stress marker, in small pulmonary vessels (CN 5.12 ± 0.84 vs. MN 1.14 ± 0.34, p < 0.05). Conclusion: Postnatal administration of melatonin blunts the cardiopulmonary response to hypoxia, reduces the pathological vascular remodeling, and increases angiogenesis in pulmonary hypertensive neonatal lambs.These effects improve the pulmonary vascular structure and function in the neonatal period under chronic hypoxia.
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Affiliation(s)
- Cristian R Astorga
- Laboratory of Vascular Function & Reactivity, Pathophysiology Program, ICBM, Faculty of Medicine, Universidad de Chile, Santiago, Chile
| | - Alejandro González-Candia
- Laboratory of Vascular Function & Reactivity, Pathophysiology Program, ICBM, Faculty of Medicine, Universidad de Chile, Santiago, Chile
| | - Alejandro A Candia
- Laboratory of Vascular Function & Reactivity, Pathophysiology Program, ICBM, Faculty of Medicine, Universidad de Chile, Santiago, Chile.,Department for the Woman and Newborn Health Promotion, Universidad de Chile, Santiago, Chile
| | - Esteban G Figueroa
- Laboratory of Vascular Function & Reactivity, Pathophysiology Program, ICBM, Faculty of Medicine, Universidad de Chile, Santiago, Chile
| | - Daniel Cañas
- Department of Mechanical Engineering, Faculty of Engineering, Universidad de Santiago de Chile, Santiago, Chile
| | - Germán Ebensperger
- Perinatal Physiology and Pathophysiology Unit, Pathophysiology Program, ICBM, Faculty of Medicine, Universidad de Chile, Santiago, Chile.,International Center for Andean Studies, Universidad de Chile, Santiago, Chile
| | - Roberto V Reyes
- Perinatal Physiology and Pathophysiology Unit, Pathophysiology Program, ICBM, Faculty of Medicine, Universidad de Chile, Santiago, Chile.,International Center for Andean Studies, Universidad de Chile, Santiago, Chile
| | - Aníbal J Llanos
- Perinatal Physiology and Pathophysiology Unit, Pathophysiology Program, ICBM, Faculty of Medicine, Universidad de Chile, Santiago, Chile.,International Center for Andean Studies, Universidad de Chile, Santiago, Chile
| | - Emilio A Herrera
- Laboratory of Vascular Function & Reactivity, Pathophysiology Program, ICBM, Faculty of Medicine, Universidad de Chile, Santiago, Chile.,Perinatal Physiology and Pathophysiology Unit, Pathophysiology Program, ICBM, Faculty of Medicine, Universidad de Chile, Santiago, Chile.,International Center for Andean Studies, Universidad de Chile, Santiago, Chile
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20
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Zhang Z, Xiao Z, Deng B, Liu X, Liu W, Nie H, Li X, Chen Z, Yang D, Duan R. Therapeutic Efficacy of Methazolamide Against Intermittent Hypoxia-Induced Excessive Erythrocytosis in Rats. High Alt Med Biol 2018; 19:69-80. [DOI: 10.1089/ham.2017.0044] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Affiliation(s)
- Zhiqing Zhang
- Tianjin Institute of Health and Environmental Medicine, Tianjin, China
| | - Zhonghai Xiao
- Tianjin Institute of Health and Environmental Medicine, Tianjin, China
| | - Bingnan Deng
- Tianjin Institute of Health and Environmental Medicine, Tianjin, China
| | - Xiaohua Liu
- Tianjin Institute of Health and Environmental Medicine, Tianjin, China
| | - Wei Liu
- Tianjin Institute of Health and Environmental Medicine, Tianjin, China
| | - Hongjing Nie
- Tianjin Institute of Health and Environmental Medicine, Tianjin, China
| | - Xi Li
- Tianjin Institute of Health and Environmental Medicine, Tianjin, China
| | - Zhaoli Chen
- Tianjin Institute of Health and Environmental Medicine, Tianjin, China
| | - Danfeng Yang
- Tianjin Institute of Health and Environmental Medicine, Tianjin, China
| | - Ruifeng Duan
- Tianjin Institute of Health and Environmental Medicine, Tianjin, China
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21
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Aguilar M, González-Candia A, Rodríguez J, Carrasco-Pozo C, Cañas D, García-Herrera C, Herrera EA, Castillo RL. Mechanisms of Cardiovascular Protection Associated with Intermittent Hypobaric Hypoxia Exposure in a Rat Model: Role of Oxidative Stress. Int J Mol Sci 2018; 19:ijms19020366. [PMID: 29373484 PMCID: PMC5855588 DOI: 10.3390/ijms19020366] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Revised: 01/08/2018] [Accepted: 01/09/2018] [Indexed: 12/25/2022] Open
Abstract
More than 140 million people live and works (in a chronic or intermittent form) above 2500 m worldwide and 35 million live in the Andean Mountains. Furthermore, in Chile, it is estimated that 55,000 persons work in high altitude shifts, where stays at lowlands and interspersed with working stays at highlands. Acute exposure to high altitude has been shown to induce oxidative stress in healthy human lowlanders, due to an increase in free radical formation and a decrease in antioxidant capacity. However, in animal models, intermittent hypoxia (IH) induce preconditioning, like responses and cardioprotection. Here, we aimed to describe in a rat model the responses on cardiac and vascular function to 4 cycles of intermittent hypobaric hypoxia (IHH). Twelve adult Wistar rats were randomly divided into two equal groups, a four-cycle of IHH, and a normobaric hypoxic control. Intermittent hypoxia was induced in a hypobaric chamber in four continuous cycles (1 cycle = 4 days hypoxia + 4 days normoxia), reaching a barometric pressure equivalent to 4600 m of altitude (428 Torr). At the end of the first and fourth cycle, cardiac structural, and functional variables were determined by echocardiography. Thereafter, ex vivo vascular function and biomechanical properties were determined in femoral arteries by wire myography. We further measured cardiac oxidative stress biomarkers (4-Hydroxy-nonenal, HNE; nytrotirosine, NT), reactive oxygen species (ROS) sources (NADPH and mitochondrial), and antioxidant enzymes activity (catalase, CAT; glutathione peroxidase, GPx, and superoxide dismutase, SOD). Our results show a higher ejection and shortening fraction of the left ventricle function by the end of the 4th cycle. Further, femoral vessels showed an improvement of vasodilator capacity and diminished stiffening. Cardiac tissue presented a higher expression of antioxidant enzymes and mitochondrial ROS formation in IHH, as compared with normobaric hypoxic controls. IHH exposure determines a preconditioning effect on the heart and femoral artery, both at structural and functional levels, associated with the induction of antioxidant defence mechanisms. However, mitochondrial ROS generation was increased in cardiac tissue. These findings suggest that initial states of IHH are beneficial for cardiovascular function and protection.
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Affiliation(s)
- Miguel Aguilar
- Programa de Fisiopatología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago 7500922, Chile.
| | - Alejandro González-Candia
- Programa de Fisiopatología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago 7500922, Chile.
| | - Jorge Rodríguez
- Programa de Fisiopatología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago 7500922, Chile.
- Departamento de Kinesiología, Facultad de Medicina, Universidad de Chile, Santiago 8380453, Chile.
| | - Catalina Carrasco-Pozo
- Discovery Biology, Griffith Institute for Drug Discovery, Griffith University, Brisbane, QLD 4222, Australia.
- Departamento de Nutrición, Facultad de Medicina, Universidad de Chile, Santiago 8380453, Chile.
| | - Daniel Cañas
- Departamento de Ingeniería Mecánica, Facultad de Ingeniería, Universidad de Santiago de Chile, Santiago 9170125, Chile.
| | - Claudio García-Herrera
- Departamento de Ingeniería Mecánica, Facultad de Ingeniería, Universidad de Santiago de Chile, Santiago 9170125, Chile.
| | - Emilio A Herrera
- Programa de Fisiopatología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago 7500922, Chile.
- International Center for Andean Studies, Universidad de Chile, Putre, Chile.
| | - Rodrigo L Castillo
- Programa de Fisiopatología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago 7500922, Chile.
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22
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Zhu H, Jin Q, Li Y, Ma Q, Wang J, Li D, Zhou H, Chen Y. Melatonin protected cardiac microvascular endothelial cells against oxidative stress injury via suppression of IP3R-[Ca 2+]c/VDAC-[Ca 2+]m axis by activation of MAPK/ERK signaling pathway. Cell Stress Chaperones 2018; 23:101-113. [PMID: 28669047 PMCID: PMC5741585 DOI: 10.1007/s12192-017-0827-4] [Citation(s) in RCA: 148] [Impact Index Per Article: 24.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Revised: 06/14/2017] [Accepted: 06/21/2017] [Indexed: 10/19/2022] Open
Abstract
The cardiac microvascular reperfusion injury is characterized by the microvascular endothelial cells (CMECs) oxidative damage which is responsible for the progression of cardiac dysfunction. However, few strategies are available to reverse such pathologies. This study aimed to explore the mechanism by which oxidative stress induced CMECs death and the beneficial actions of melatonin on CMECs survival, with a special focused on IP3R-[Ca2+]c/VDAC-[Ca2+]m damage axis and the MAPK/ERK survival signaling. We found that oxidative stress induced by H2O2 significantly activated cAMP response element binding protein (CREB) that enhanced IP3R and VDAC transcription and expression, leading to [Ca2+]c and [Ca2+]m overload. High concentration of [Ca2+]m suppressed ΔΨm, opened mPTP, and released cyt-c into cytoplasm where it activated mitochondria-dependent death pathway. However, melatonin could protect CMECs against oxidative stress injury via stimulation of MAPK/ERK that inactivated CREB and therefore blocked IP3R/VDAC upregulation and [Ca2+]c/[Ca2+]m overload, sustaining mitochondrial structural and function integrity and ultimately blockading mitochondrial-mediated cellular death. In summary, these findings confirmed the mechanisms by which oxidative injury induced CMECs mitochondrial-involved death and provided an attractive and effective way to enhance CMECs survival.
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Affiliation(s)
- Hang Zhu
- Department of Cardiology, Chinese PLA General Hospital, #28 Fuxing Rd, Beijing, 100853, China
| | - Qinhua Jin
- Department of Cardiology, Chinese PLA General Hospital, #28 Fuxing Rd, Beijing, 100853, China
| | - Yang Li
- Department of Cardiology, Chinese PLA General Hospital, #28 Fuxing Rd, Beijing, 100853, China
| | - Qiang Ma
- Department of Cardiology, Chinese PLA General Hospital, #28 Fuxing Rd, Beijing, 100853, China
| | - Jing Wang
- Department of Cardiology, Chinese PLA General Hospital, #28 Fuxing Rd, Beijing, 100853, China
| | - Dandan Li
- Department of Cardiology, Chinese PLA General Hospital, #28 Fuxing Rd, Beijing, 100853, China
| | - Hao Zhou
- Department of Cardiology, Chinese PLA General Hospital, #28 Fuxing Rd, Beijing, 100853, China.
| | - Yundai Chen
- Department of Cardiology, Chinese PLA General Hospital, #28 Fuxing Rd, Beijing, 100853, China.
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