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Characterization of a murine model of endothelial dysfunction induced by chronic intraperitoneal administration of angiotensin II. Sci Rep 2021; 11:21193. [PMID: 34707201 PMCID: PMC8551243 DOI: 10.1038/s41598-021-00676-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Accepted: 10/14/2021] [Indexed: 02/05/2023] Open
Abstract
Endothelial dysfunction (ED) is a key factor for the development of cardiovascular diseases. Due to its chronic, life-threatening nature, ED only can be studied experimentally in animal models. Therefore, this work was aimed to characterize a murine model of ED induced by a daily intraperitoneal administration of angiotensin II (AGII) for 10 weeks. Oxidative stress, inflammation, vascular remodeling, hypertension, and damage to various target organs were evaluated in treated animals. The results indicated that a chronic intraperitoneal administration of AGII increases the production of systemic soluble VCAM, ROS and ICAM-1 expression, and the production of TNFα, IL1β, IL17A, IL4, TGFβ, and IL10 in the kidney, as well as blood pressure levels; it also promotes vascular remodeling and induces non-alcoholic fatty liver disease, glomerulosclerosis, and proliferative retinopathy. Therefore, the model herein proposed can be a representative model for ED; additionally, it is easy to implement, safe, rapid, and inexpensive.
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Gao HR, Wu ZJ, Wu SB, Gao HY, Wang J, Zhang JL, Zhou MQ. Roles of central orexinergic system on cardiovascular function and acupuncture on intervention of cardiovascular risk: Orexinergic system mediate the role of acupuncture? Neuropeptides 2021; 87:102132. [PMID: 33636511 DOI: 10.1016/j.npep.2021.102132] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Revised: 01/09/2021] [Accepted: 02/11/2021] [Indexed: 12/26/2022]
Abstract
Central orexinergic system contributes to the regulation of cardiovascular function. Orexinergic neurons receiving projections of nerve fibers from multiple structures of brain which involved in control and regulation of cardiovascular function locate in hypothalamus, and their axon terminals widely project to various central structures where orexins receptors are expressed. Here, we summarize the present knowledge that describes the influence of central orexinergic system on cardiovascular activity, the relevance of dysfunction in central orexinergic system with hypertension and psychological stress induced cardiovascular reactivity which are serious risk factors for cardiovascular disease and cardiovascular death. We propose that central orexinergic system may be potentially important targets for the prevention of cardiovascular disease and cardiovascular death, and different orexinergic system involved neuronal circuits may be involved in distinct cardiovascular functions. Acupuncture having bidirectional regulatory ability and a much lower incidence of side effects can prevent disease. We review the improvement of acupuncture on hypertension and psychological stress induced cardiovascular reactivity. We think that acupuncture intervenes hypertension and psychological stress induced cardiovascular reactivity to prevent cardiovascular disease and cardiovascular death. We also summarize relation between acupuncture and central orexinergic system. We propose a hypothesis that acupuncture improve hypertension and psychological stress induced cardiovascular reactivity through regulating central orexinergic system. The knowledge is beneficial for the development of potential therapeutic targets and methods to prevent cardiovascular disease and cardiovascular death.
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Affiliation(s)
- He-Ren Gao
- Key Laboratory of Acupuncture and Moxibustion Foundation and Technology of Anhui Province, Research Institute of Acupuncture and Meridian, College of Acupuncture and Tuina, Anhui Academy of Chinese Medicine, Anhui University of Chinese Medicine, Hefei, China.
| | - Zi-Jian Wu
- Key Laboratory of Acupuncture and Moxibustion Foundation and Technology of Anhui Province, Research Institute of Acupuncture and Meridian, College of Acupuncture and Tuina, Anhui Academy of Chinese Medicine, Anhui University of Chinese Medicine, Hefei, China
| | - Sheng-Bing Wu
- Key Laboratory of Acupuncture and Moxibustion Foundation and Technology of Anhui Province, Research Institute of Acupuncture and Meridian, College of Acupuncture and Tuina, Anhui Academy of Chinese Medicine, Anhui University of Chinese Medicine, Hefei, China; Key Laboratory of Xin'an Medicine, Ministry of Education, Anhui University of Chinese Medicine, Hefei, China
| | - He-Yuan Gao
- Department of Pediatrics, The First Hospital of Qinhuangdao, Qinhuangdao, China
| | - Jie Wang
- Key Laboratory of Acupuncture and Moxibustion Foundation and Technology of Anhui Province, Research Institute of Acupuncture and Meridian, College of Acupuncture and Tuina, Anhui Academy of Chinese Medicine, Anhui University of Chinese Medicine, Hefei, China
| | - Jin-Li Zhang
- Anhui Vocational College of Grain Engineering, Hefei, China
| | - Mei-Qi Zhou
- Key Laboratory of Acupuncture and Moxibustion Foundation and Technology of Anhui Province, Research Institute of Acupuncture and Meridian, College of Acupuncture and Tuina, Anhui Academy of Chinese Medicine, Anhui University of Chinese Medicine, Hefei, China; Key Laboratory of Xin'an Medicine, Ministry of Education, Anhui University of Chinese Medicine, Hefei, China; Bozhou Institute of Traditional Chinese Medicine, Anhui Academy of Chinese Medicine, Bozhou, China.
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3
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A SARS-CoV-2 -human metalloproteome interaction map. J Inorg Biochem 2021; 219:111423. [PMID: 33813307 PMCID: PMC7955571 DOI: 10.1016/j.jinorgbio.2021.111423] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Revised: 02/16/2021] [Accepted: 03/08/2021] [Indexed: 12/12/2022]
Abstract
The recent pandemic caused by the novel coronavirus resulted in the greatest global health crisis since the Spanish flu pandemic of 1918. There is limited knowledge of whether SARS-CoV-2 is physically associated with human metalloproteins. Recently, high-confidence, experimentally supported protein-protein interactions between SARS-CoV-2 and human proteins were reported. In this work, 58 metalloproteins among these human targets have been identified by a structure-based approach. This study reveals that most human metalloproteins interact with the recently discovered SARS-CoV-2 orf8 protein, whose antibodies are one of the principal markers of SARS-CoV-2 infections. Furthermore, this work provides sufficient evidence to conclude that Zn2+ plays an important role in the interplay between the novel coronavirus and humans. First, the content of Zn-binding proteins in the involved human metalloproteome is significantly higher than that of the other metal ions. Second, a molecular linkage between the identified human Zn-binding proteome with underlying medical conditions, that might increase the risk of severe illness from the SARS-CoV-2 virus, has been found. Likely perturbations of host cellular metal homeostasis by SARS-CoV-2 infection are highlighted.
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Bigalke JA, Gao H, Chen QH, Shan Z. Activation of Orexin 1 Receptors in the Paraventricular Nucleus Contributes to the Development of Deoxycorticosterone Acetate-Salt Hypertension Through Regulation of Vasopressin. Front Physiol 2021; 12:641331. [PMID: 33633591 PMCID: PMC7902066 DOI: 10.3389/fphys.2021.641331] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Accepted: 01/13/2021] [Indexed: 12/13/2022] Open
Abstract
Salt-sensitivity is a major factor in the development of hypertension. The brain orexin system has been observed to play a role in numerous hypertensive animal models. However, orexin’s role in the pathology of salt-sensitive hypertension (SSH) remains to be adequately explored. We assessed the impact of orexin hyperactivity in the pathogenesis of the deoxycorticosterone acetate (DOCA) – salt rat model, specifically through modulation of Arginine Vasopressin (AVP). Adult male rats were separated into three groups: vehicle control, DOCA-salt, and DOCA-salt+OX1R-shRNA. DOCA-salt rats received subcutaneous implantation of a 21-day release, 75 mg DOCA pellet in addition to saline drinking water (1% NaCl and 0.2% KCl). DOCA-salt+OX1R-shRNA rats received bilateral microinjection of AAV2-OX1R-shRNA into the paraventricular nucleus (PVN) to knockdown function of the Orexin 1-Receptor (OX1R) within that area. Following 2-week to allow full transgene expression, a DOCA pellet was administered in addition to saline drinking solution. Vehicle controls received sham DOCA implantation but were given normal water. During the 3-week DOCA-salt or sham treatment period, mean arterial pressure (MAP) and heart rate (HR) were monitored utilizing tail-cuff plethysmography. Following the 3-week period, rat brains were collected for either PCR mRNA analysis, as well as immunostaining. Plasma samples were collected and subjected to ELISA analysis. In line with our hypothesis, OX1R expression was elevated in the PVN of DOCA-salt treated rats when compared to controls. Furthermore, following chronic knockdown of OX1R, the hypertension development normally induced by DOCA-salt treatment was significantly diminished in the DOCA-salt+OX1R-shRNA group. A concurrent reduction in PVN OX1R and AVP mRNA was observed in concert with the reduced blood pressure following AAV2-OX1R-shRNA treatment. Similarly, plasma AVP concentrations appeared to be reduced in the DOCA-salt+OX1R-shRNA group when compared to DOCA-salt rats. These results indicate that orexin signaling, specifically through the OX1R in the PVN are critical for the onset and maintenance of hypertension in the DOCA-salt model. This relationship is mediated, at least in part, through orexin activation of AVP producing neurons, and the subsequent release of AVP into the periphery. Our results outline a promising mechanism underlying the development of SSH through interactions with the brain orexin system.
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Affiliation(s)
- Jeremy A Bigalke
- Department of Kinesiology and Integrative Physiology, Michigan Technological University, Houghton, MI, United States.,Department of Psychology, Montana State University, Bozeman, MT, United States
| | - Huanjia Gao
- Department of Kinesiology and Integrative Physiology, Michigan Technological University, Houghton, MI, United States.,The Second Clinical College of Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Qing-Hui Chen
- Department of Kinesiology and Integrative Physiology, Michigan Technological University, Houghton, MI, United States.,Health Research Institute, Michigan Technological University, Houghton, MI, United States
| | - Zhiying Shan
- Department of Kinesiology and Integrative Physiology, Michigan Technological University, Houghton, MI, United States.,Health Research Institute, Michigan Technological University, Houghton, MI, United States
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Head GA. Integrative Physiology: Update to the Grand Challenge 2020. Front Physiol 2020; 11:489. [PMID: 32499720 PMCID: PMC7243031 DOI: 10.3389/fphys.2020.00489] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2020] [Accepted: 04/21/2020] [Indexed: 11/13/2022] Open
Affiliation(s)
- Geoffrey A Head
- Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
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Jackson KL, Head GA, Gueguen C, Stevenson ER, Lim K, Marques FZ. Mechanisms Responsible for Genetic Hypertension in Schlager BPH/2 Mice. Front Physiol 2019; 10:1311. [PMID: 31681017 PMCID: PMC6813185 DOI: 10.3389/fphys.2019.01311] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2019] [Accepted: 09/30/2019] [Indexed: 01/18/2023] Open
Abstract
It has been 45 years since Gunther Schlager used a cross breeding program in mice to develop inbred strains with high, normal, and low blood pressure (BPH/2, BPN/3, and BPL/1 respectively). Thus, it is timely to gather together the studies that have characterized and explored the mechanisms associated with the hypertension to take stock of exactly what is known and what remains to be determined. Growing evidence supports the notion that the mechanism of hypertension in BPH/2 mice is predominantly neurogenic with some of the early studies showing aberrant brain noradrenaline levels in BPH/2 compared with BPN/3. Analysis of the adrenal gland using microarray suggested an association with the activity of the sympathetic nervous system. Indeed, in support of this, there is a larger depressor response to ganglion blockade, which reduced blood pressure in BPH/2 mice to the same level as BPN/3 mice. Greater renal tyrosine hydroxylase staining and greater renal noradrenaline levels in BPH/2 mice suggest sympathetic hyperinnervation of the kidney. Renal denervation markedly reduced the blood pressure in BPH/2 but not BPN/3 mice, confirming the importance of renal sympathetic nervous activity contributing to the hypertension. Further, there is an important contribution to the hypertension from miR-181a and renal renin in this strain. BPH/2 mice also display greater neuronal activity of amygdalo-hypothalamic cardiovascular regulatory regions. Lesions of the medial nucleus of the amygdala reduced the hypertension in BPH/2 mice and abolished the strain difference in the effect of ganglion blockade, suggesting a sympathetic mechanism. Further studies suggest that aberrant GABAergic inhibition may play a role since BPH/2 mice have low GABAA receptor δ, α4 and β2 subunit mRNA expression in the hypothalamus, which are predominantly involved in promoting tonic neuronal inhibition. Allopregnanolone, an allosteric modulator of GABAA receptors, which increase the expression of these subunits in the amygdala and hypothalamus, is shown to reduce the hypertension and sympathetic nervous system contribution in BPH/2 mice. Thus far, evidence suggests that BPH/2 mice have aberrant GABAergic inhibition, which drives neuronal overactivity within amygdalo-hypothalamic brain regions. This overactivity is responsible for the greater sympathetic contribution to the hypertension in BPH/2 mice, thus making this an ideal model of neurogenic hypertension.
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Affiliation(s)
- Kristy L Jackson
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
| | - Geoffrey A Head
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
| | - Cindy Gueguen
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
| | - Emily R Stevenson
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
| | - Kyungjoon Lim
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia.,Department of Physiology, Anatomy and Microbiology, School of Life Sciences, La Trobe University, Melbourne, VIC, Australia
| | - Francine Z Marques
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia.,Hypertension Research Laboratory, School of Biological Sciences, Monash University, Clayton, VIC, Australia
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Trejo-Moreno C, Castro-Martínez G, Méndez-Martínez M, Jiménez-Ferrer JE, Pedraza-Chaverri J, Arrellín G, Zamilpa A, Medina-Campos ON, Lombardo-Earl G, Barrita-Cruz GJ, Hernández B, Ramírez CC, Santana MA, Fragoso G, Rosas G. Acetone fraction from Sechium edule (Jacq.) S.w. edible roots exhibits anti-endothelial dysfunction activity. JOURNAL OF ETHNOPHARMACOLOGY 2018; 220:75-86. [PMID: 29501845 DOI: 10.1016/j.jep.2018.02.036] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2017] [Revised: 02/22/2018] [Accepted: 02/23/2018] [Indexed: 06/08/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE A recent ethnomedical survey on medicinal plants grown in Mexico revealed that Sechium edule (Jacq.) Sw. (Cucurbitaceae) is one of the most valued plant species to treat cardiovascular diseases, including hypertension. Fruits, young leaves, buds, stems, and tuberous roots of the plant are edible. Considering that endothelial dysfunction induced by Angiotensin II plays an important role in the pathogenesis of hypertension and is accompanied by a prooxidative condition, which in turn induces an inflammatory state, vascular remodeling, and tissue damage, and that S. edule has been reported to possess antioxidant, anti-inflammatory and antihypertensive activity, its capability to control endothelial dysfunction was also assessed. AIM OF THE STUDY To assess in vivo the anti-endothelial dysfunction activity of the acetone fraction (rSe-ACE) of the hydroalcoholic extract from S. edule roots. MATERIALS AND METHODS Endothelial dysfunction was induced in female C57BL/6 J mice by a daily intraperitoneal injection of angiotensin II for 10 weeks. Either rSe-ACE or losartan (as a control) were co-administered with angiotensin II for the same period. Blood pressure was measured at weeks 0, 5, and 10. Kidney extracts were prepared to determine IL1β, IL4, IL6, IL10, IL17, IFNγ, TNFα, and TGFβ levels by ELISA, along with the prooxidative status as assessed by the activity of antioxidant enzymes. The expression of ICAM-1 was evaluated by immunohistochemistry in kidney histological sections. Kidney and hepatic damage, as well as vascular tissue remodeling, were studied. RESULTS The rSe-ACE fraction administered at a dose of 10 mg/kg was able to control hypertension, as well as the prooxidative and proinflammatory status in kidney as efficiently as losartan, returning mice to normotensive levels. Additionally, the fraction was more efficient than losartan to prevent liver and kidney damage. Phytochemical characterization identified cinnamic acid as a major compound, and linoleic, palmitic, and myristic acids as the most abundant non-polar components in the mixture, previously reported to aid in the control of hypertension, inflammation, and oxidative stress, three important components of endothelial dysfunction. IN CONCLUSION this study demonstrated that rSe-ACE has anti-endothelial dysfunction activity in an experimental model and highlights the role of cinnamic acid and fatty acids in the observed effects.
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Affiliation(s)
- Celeste Trejo-Moreno
- Facultad de Medicina, Universidad Autónoma del Estado de Morelos, Cuernavaca, Morelos CP 62350, Mexico
| | - Gabriela Castro-Martínez
- Facultad de Medicina, Universidad Autónoma del Estado de Morelos, Cuernavaca, Morelos CP 62350, Mexico
| | - Marisol Méndez-Martínez
- Facultad de Medicina, Universidad Autónoma del Estado de Morelos, Cuernavaca, Morelos CP 62350, Mexico
| | - Jesús Enrique Jiménez-Ferrer
- Laboratorio de Farmacología, Centro de Investigaciones Biomédicas del Sur, Instituto Mexicano del Seguro Social, Xochitepec, Morelos CP 62790, Mexico
| | - José Pedraza-Chaverri
- Facultad de Química, Universidad Nacional Autónoma de México, Coyoacán, Ciudad de México CP 04510, Mexico
| | - Gerardo Arrellín
- Facultad de Medicina, Universidad Autónoma del Estado de Morelos, Cuernavaca, Morelos CP 62350, Mexico; Facultad de Ciencias de la Salud, Universidad Panamericana, Ciudad de México CP 03920, Mexico
| | - Alejandro Zamilpa
- Laboratorio de Farmacología, Centro de Investigaciones Biomédicas del Sur, Instituto Mexicano del Seguro Social, Xochitepec, Morelos CP 62790, Mexico
| | - Omar Noel Medina-Campos
- Facultad de Química, Universidad Nacional Autónoma de México, Coyoacán, Ciudad de México CP 04510, Mexico
| | - Galia Lombardo-Earl
- Laboratorio de Farmacología, Centro de Investigaciones Biomédicas del Sur, Instituto Mexicano del Seguro Social, Xochitepec, Morelos CP 62790, Mexico
| | - Gerardo Joel Barrita-Cruz
- Facultad de Medicina, Universidad Autónoma del Estado de Morelos, Cuernavaca, Morelos CP 62350, Mexico
| | - Beatriz Hernández
- Facultad de Medicina, Universidad Nacional Autónoma de México, Coyoacán, Ciudad de México CP 04510, Mexico
| | - Christian Carlos Ramírez
- Facultad de Medicina, Universidad Autónoma del Estado de Morelos, Cuernavaca, Morelos CP 62350, Mexico
| | - María Angélica Santana
- Centro de Investigación en Dinámica Celular, Universidad Autónoma del Estado de Morelos, Av. Universidad 1001, Chamilpa, Cuernavaca, Morelos CP 62209, Mexico
| | - Gladis Fragoso
- Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Coyoacán, Ciudad de México CP 04510, Mexico
| | - Gabriela Rosas
- Facultad de Medicina, Universidad Autónoma del Estado de Morelos, Cuernavaca, Morelos CP 62350, Mexico.
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Jackson KL, Marques FZ, Lim K, Davern PJ, Head GA. Circadian Differences in the Contribution of the Brain Renin-Angiotensin System in Genetically Hypertensive Mice. Front Physiol 2018; 9:231. [PMID: 29615926 PMCID: PMC5868475 DOI: 10.3389/fphys.2018.00231] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Accepted: 03/01/2018] [Indexed: 11/21/2022] Open
Abstract
Objective: Genetically hypertensive BPH/2J mice are recognized as a neurogenic model of hypertension, primarily based on sympathetic overactivity and greater neuronal activity in cardiovascular regulatory brain regions. Greater activity of the central renin angiotensin system (RAS) and reactive oxygen species (ROS) reportedly contribute to other models of hypertension. Importantly the peripheral RAS contributes to the hypertension in BPH/2J mice, predominantly during the dark period of the 24 h light cycle. The aim of the present study was to determine whether central AT1 receptor stimulation and the associated ROS signaling contribute to hypertension in BPH/2J mice in a circadian dependent manner. Methods: Blood pressure (BP) was measured in BPH/2J and normotensive BPN/3J mice (n = 7–8) via pre-implanted telemetry devices. Acute intracerebroventricular (ICV) microinjections of AT1 receptor antagonist, candesartan, and the superoxide dismutase (SOD) mimetic, tempol, were administered during the dark and light period of the 24 h light cycle via a pre-implanted ICV guide cannula. In separate mice, the BP effect of ICV infusion of the AT1 receptor antagonist losartan for 7 days was compared with subcutaneous infusion to determine the contribution of the central RAS to hypertension in BPH/2J mice. Results: Candesartan administered ICV during the dark period induced depressor responses which were 40% smaller in BPH/2J than BPN/3J mice (Pstrain < 0.05), suggesting AT1 receptor stimulation may contribute less to BP maintenance in BPH/2J mice. During the light period candesartan had minimal effect on BP in either strain. ICV tempol had comparable effects on BP between strains during the light and dark period (Pstrain > 0.08), suggesting ROS signaling is also not contributing to the hypertension in BPH/2J mice. Chronic ICV administration of losartan (22 nmol/h) had minimal effect on BPN/3J mice. By contrast in BPH/2J mice, both ICV and subcutaneously administered losartan induced similar hypotensive responses (−12.1 ± 1.8 vs. −14.7 ± 1.8 mmHg, Proute = 0.31). Conclusion: While central effects of peripheral losartan cannot be excluded, we suggest the hypotensive effect of chronic ICV losartan was likely peripherally mediated. Thus, based on both acute and chronic AT1 receptor inhibition and acute ROS inhibition, our findings suggest that greater activation of central AT1 receptors or ROS are unlikely to be mediating the hypertension in BPH/2J mice.
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Affiliation(s)
- Kristy L Jackson
- Neuropharmacology Laboratory, Baker Heart and Diabetes Research Institute, Melbourne, VIC, Australia
| | - Francine Z Marques
- Department of Pharmacology, Monash University, Victoria, VIC, Australia.,Heart Failure Research Group, Baker Heart and Diabetes Research Institute, Melbourne, VIC, Australia
| | - Kyungjoon Lim
- Neuropharmacology Laboratory, Baker Heart and Diabetes Research Institute, Melbourne, VIC, Australia.,Department of Physiology, Anatomy and Microbiology, Latrobe University, Bundoora, VIC, Australia
| | - Pamela J Davern
- Neuropharmacology Laboratory, Baker Heart and Diabetes Research Institute, Melbourne, VIC, Australia
| | - Geoffrey A Head
- Neuropharmacology Laboratory, Baker Heart and Diabetes Research Institute, Melbourne, VIC, Australia.,Department of Pharmacology, Monash University, Victoria, VIC, Australia
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Abstract
PURPOSE OF REVIEW The major health issue of being overweight or obese relates to the development of hypertension, insulin resistance and diabetic complications. One of the major underlying factors influencing the elevated blood pressure in obesity is increased activity of the sympathetic nerves to particular organs such as the kidney. RECENT FINDINGS There is now convincing evidence from animal studies that major signals such as leptin and insulin have a sympathoexcitatory action in the hypothalamus to cause hypertension. Recent studies suggest that this may involve 'neural plasticity' within hypothalamic signalling driven by central actions of leptin mediated via activation of melanocortin receptor signalling and activation of brain neurotrophic factors. This review describes the evidence to support the contribution of the SNS to obesity related hypertension and the major metabolic and adipokine signals.
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10
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Vibhuti, Khan R, Sharma A, Jain S, Mohanty S, Prasad K. Intra-arterial transplantation of human bone marrow mesenchymal stem cells (hBMMSCs) improves behavioral deficits and alters gene expression in rodent stroke model. J Neurochem 2017; 143:722-735. [PMID: 29049855 DOI: 10.1111/jnc.14241] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Revised: 09/29/2017] [Accepted: 10/11/2017] [Indexed: 12/17/2022]
Abstract
Stroke is a multi-factorial polygenic disease and is a major cause of death and adult disability. Administration of bone marrow stem cells protects ischemic rat brain by facilitating recovery of neurological functions. But the molecular mechanism of stem cells action and their effect on gene expression is not well explored. In this study, we have transplanted 1 × 106 human bone marrow mesenchymal stem cells (hBMMSCs) in middle cerebral artery occluded (MCAo) adult male Wistar rats through intracarotid artery route at 24 h after surgery. Motor behavioral tests (rotarod and open field) were performed to assess the changes in motor functions at day 0 and day1, 4, 8 and 14. The expression of studied genes at mRNA and protein level was quantified by using Q-PCR and western blotting, respectively. Further, we have assessed the methylation pattern of promoter of these genes by using methylation-specific PCR. Data were analyzed statistically and correlated. A significant improvement in behavioral deficits was observed in stem cells treated group after 14th day post stroke. Significantly (p < 0.05) increased mRNA and protein levels of brain derived neurotrophic factor and ANP genes in hBMMSCs treated group along with decrease in methylation level at their promoter was observed. On the other hand, significantly decreased mRNA and protein level of TSP1 and WNK1 in hBMMSCs treated group was observed. In conclusion, hBMMSCs administration significantly improves the behavioral deficits by improving motor and locomotor coordination. The promoter of TSP1 and WNK1 genes was found to be hyper-methylated in hBMMSCs group resulting in their decreased expression while the promoter of ANP and brain derived neurotrophic factor was found to be hypo-methylated. This study might shed a light on how hBMMSCs affect the gene expression by modulating methylation status.
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Affiliation(s)
- Vibhuti
- Department of Neurology, All India Institute of Medical Sciences (AIIMS), New Delhi, India
| | - Rehan Khan
- Department of Biochemistry, All India Institute of Medical Sciences (AIIMS), New Delhi, India
| | - Alpana Sharma
- Department of Biochemistry, All India Institute of Medical Sciences (AIIMS), New Delhi, India
| | - Suman Jain
- Department of Physiology, All India Institute of Medical Sciences (AIIMS), New Delhi, India
| | - Sujata Mohanty
- Stem Cell Facility, All India Institute of Medical Sciences (AIIMS), New Delhi, India
| | - Kameshwar Prasad
- Department of Neurology, All India Institute of Medical Sciences (AIIMS), New Delhi, India
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12
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Huber MJ, Chen QH, Shan Z. The Orexin System and Hypertension. Cell Mol Neurobiol 2017; 38:385-391. [PMID: 28349223 DOI: 10.1007/s10571-017-0487-z] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Accepted: 03/18/2017] [Indexed: 12/18/2022]
Abstract
In this review, we focus on the role of orexin signaling in blood pressure control and its potential link to hypertension by summarizing evidence from several experimental animal models of hypertension. Studies using the spontaneously hypertensive rat (SHR) animal model of human essential hypertension show that pharmacological blockade of orexin receptors reduces blood pressure in SHRs but not in Wistar-Kyoto rats. In addition, increased activity of the orexin system contributes to elevated blood pressure and sympathetic nerve activity (SNA) in dark-active period Schlager hypertensive (BPH/2J) mice, another genetic model of neurogenic hypertension. Similar to these two models, Sprague-Dawley rats with stress-induced hypertension display an overactive central orexin system. Furthermore, upregulation of the orexin receptor 1 increases firing of hypothalamic paraventricular nucleus neurons, augments SNA, and contributes to hypertension in the obese Zucker rat, an animal model of obesity-related hypertension. Finally, we propose a hypothesis for the implication of the orexin system in salt-sensitive hypertension. All of this evidence, coupled with the important role of elevated SNA in increasing blood pressure, strongly suggests that hyperactivity of the orexin system contributes to hypertension.
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Affiliation(s)
- Michael J Huber
- Department of Kinesiology and Integrative Physiology, Michigan Technological University, SDC 231, 1400 Townsend Drive, Houghton, MI, 49931, USA
| | - Qing-Hui Chen
- Department of Kinesiology and Integrative Physiology, Michigan Technological University, SDC 231, 1400 Townsend Drive, Houghton, MI, 49931, USA
| | - Zhiying Shan
- Department of Kinesiology and Integrative Physiology, Michigan Technological University, SDC 231, 1400 Townsend Drive, Houghton, MI, 49931, USA.
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13
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Carrive P, Kuwaki T. Orexin and Central Modulation of Cardiovascular and Respiratory Function. Curr Top Behav Neurosci 2017; 33:157-196. [PMID: 27909989 DOI: 10.1007/7854_2016_46] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Orexin makes an important contribution to the regulation of cardiorespiratory function. When injected centrally under anesthesia, orexin increases blood pressure, heart rate, sympathetic nerve activity, and the amplitude and frequency of respiration. This is consistent with the location of orexin neurons in the hypothalamus and the distribution of orexin terminals at all levels of the central autonomic and respiratory network. These cardiorespiratory responses are components of arousal and are necessary to allow the expression of motivated behaviors. Thus, orexin contributes to the cardiorespiratory response to acute stressors, especially those of a psychogenic nature. Consequently, upregulation of orexin signaling, whether it is spontaneous or environmentally induced, can increase blood pressure and lead to hypertension, as is the case for the spontaneously hypertensive rat and the hypertensive BPH/2J Schlager mouse. Blockade of orexin receptors will reduce blood pressure in these animals, which could be a new pharmacological approach for the treatment of some forms of hypertension. Orexin can also magnify the respiratory reflex to hypercapnia in order to maintain respiratory homeostasis, and this may be in part why it is upregulated during obstructive sleep apnea. In this pathological condition, blockade of orexin receptors would make the apnea worse. To summarize, orexin is an important modulator of cardiorespiratory function. Acting on orexin signaling may help in the treatment of some cardiovascular and respiratory disorders.
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Affiliation(s)
- Pascal Carrive
- School of Medical Sciences, University of New South Wales, Sydney, NSW, 2052, Australia.
| | - Tomoyuki Kuwaki
- Department of Physiology, Graduate School of Medical & Dental Sciences, Kagoshima University, Kagoshima, Japan
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Orexin, Stress and Central Cardiovascular Control. A Link with Hypertension? Neurosci Biobehav Rev 2016; 74:376-392. [PMID: 27477446 DOI: 10.1016/j.neubiorev.2016.06.044] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2016] [Revised: 05/28/2016] [Accepted: 06/13/2016] [Indexed: 01/28/2023]
Abstract
Orexin, the arousal peptide, originates from neurons located in an area of the dorsal hypothalamus well known for integrating defense responses and their cardiovascular component. Orexin neurons, which are driven in large part by the limbic forebrain, send projections to many regions in the brain, including regions involved in cardiovascular control, as far down as sympathetic preganglionic neurons in the spinal cord. Central injections of orexin evoke sympathetically mediated cardiovascular responses. Conversely, blockade of orexin receptors reduce the cardiovascular responses to acute stressors, preferentially of a psychological nature. More importantly, lasting upregulation of orexin signaling can lead to a hypertensive state. This can be observed in rats exposed to chronic stress as well as in strains known to display spontaneous hypertension such as the spontaneously hypertensive rat (SHR) or the hypertensive BPH/2J Schlager mouse. Thus, there is a link between orexin, stress and hypertension, and orexin upregulation could be a factor in the development of essential hypertension. Orexin receptor antagonists have anti-hypertensive effects that could be of clinical use.
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Li Y, Zhou J, Wu Y, Lu T, Yuan M, Cui Y, Zhou Y, Yang G, Hong Y. Association of osteoporosis with genetic variants of circadian genes in Chinese geriatrics. Osteoporos Int 2016; 27:1485-1492. [PMID: 26564225 DOI: 10.1007/s00198-015-3391-8] [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: 08/31/2015] [Accepted: 10/27/2015] [Indexed: 12/21/2022]
Abstract
UNLABELLED This study was designed to investigate the association of circadian gene single nucleotide polymorphisms (SNPs) with the risk of osteoporosis. We found that the rs3781638 GG genotype was positively associated with osteoporosis prevalence in females, whereas the rs2292910 AC genotype was negatively associated with osteoporosis prevalence in a geriatric cohort. INTRODUCTION Studies have shown that disruption of endogenous circadian rhythms may increase the risk of developing type II diabetes and obesity, which are reportedly associated with osteoporosis (OP). Thus, abnormalities of circadian genes may indirectly induce OP. Here, we investigated the association of OP with 14 SNPs located in seven circadian genes. METHODS The research subjects, geriatric residents of Shanghai Minhang, China, diagnosed with OP (N = 171) or osteopenia (N = 226) or without specific diseases (N = 200), were genotyped for 14 genetic variants of circadian genes by competitive allele-specific polymerase chain reaction. The prevalence of polymorphisms among the subject groups and the association between the SNPs and osteoporosis were investigated. RESULTS Among the 14 genotyped SNPs, we found an association between the CRY2 gene rs2292910 SNP and osteoporosis (r = -0.082, p = 0.045) in the geriatric cohort. We found a decreased risk between cryptochrome 2 rs2292910 and OP (A/C odds ratio = 0.647, p = 0.044) but an increased risk between MTNR1B rs3781638 and OP (G/G odds ratio = 2.058, p = 0.044). CONCLUSION For the first time, we show that Cry 2 rs2292910 and MTNR1B rs3781638 are associated with osteoporosis in a Chinese geriatric cohort. Therefore, targeting the abnormalities of the CRY2 and MTNR1B genes may be a potential strategy to treat and/or to prevent osteoporosis.
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Affiliation(s)
- Y Li
- Central laboratory, The Fifth People's Hospital of Shanghai, Fudan University, Shanghai, 200240, China
| | - J Zhou
- Central laboratory, The Fifth People's Hospital of Shanghai, Fudan University, Shanghai, 200240, China
| | - Y Wu
- Central laboratory, The Fifth People's Hospital of Shanghai, Fudan University, Shanghai, 200240, China
| | - T Lu
- Central laboratory, The Fifth People's Hospital of Shanghai, Fudan University, Shanghai, 200240, China
| | - M Yuan
- Central laboratory, The Fifth People's Hospital of Shanghai, Fudan University, Shanghai, 200240, China
| | - Y Cui
- Central laboratory, The Fifth People's Hospital of Shanghai, Fudan University, Shanghai, 200240, China
| | - Y Zhou
- Central laboratory, The Fifth People's Hospital of Shanghai, Fudan University, Shanghai, 200240, China
| | - G Yang
- Central laboratory, The Fifth People's Hospital of Shanghai, Fudan University, Shanghai, 200240, China.
- Cancer Institute, Fudan University Shanghai Cancer Center, Shanghai, 200032, China.
- Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, 200032, China.
| | - Y Hong
- Central laboratory, The Fifth People's Hospital of Shanghai, Fudan University, Shanghai, 200240, China.
- Department of Osteology, The Fifth People's Hospital of Shanghai, Fudan University, Shanghai, 200240, China.
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Jackson KL, Dampney BW, Moretti JL, Stevenson ER, Davern PJ, Carrive P, Head GA. Contribution of Orexin to the Neurogenic Hypertension in BPH/2J Mice. Hypertension 2016; 67:959-69. [PMID: 26975709 DOI: 10.1161/hypertensionaha.115.07053] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2015] [Accepted: 02/14/2016] [Indexed: 11/16/2022]
Abstract
BPH/2J mice are a genetic model of hypertension associated with an overactive sympathetic nervous system. Orexin is a neuropeptide which influences sympathetic activity and blood pressure. Orexin precursor mRNA expression is greater in hypothalamic tissue of BPH/2J compared with normotensive BPN/3J mice. To determine whether enhanced orexinergic signaling contributes to the hypertension, BPH/2J and BPN/3J mice were preimplanted with radiotelemetry probes to compare blood pressure 1 hour before and 5 hours after administration of almorexant, an orexin receptor antagonist. Mid frequency mean arterial pressure power and the depressor response to ganglion blockade were also used as indicators of sympathetic nervous system activity. Administration of almorexant at 100 (IP) and 300 mg/kg (oral) in BPH/2J mice during the dark-active period (2 hours after lights off) markedly reduced blood pressure (-16.1 ± 1.6 and -11.0 ± 1.1 mm Hg, respectively;P<0.001 compared with vehicle). However, when almorexant (100 mg/kg, IP) was administered during the light-inactive period (5 hours before lights off) no reduction from baseline was observed (P=0.64). The same dose of almorexant in BPN/3J mice had no effect on blood pressure during the dark (P=0.79) or light periods (P=0.24). Almorexant attenuated the depressor response to ganglion blockade (P=0.018) and reduced the mid frequency mean arterial pressure power in BPH/2J mice (P<0.001), but not BPN/3J mice (P=0.70). Immunohistochemical labeling revealed that BPH/2J mice have 29% more orexin neurons than BPN/3J mice which are preferentially located in the lateral hypothalamus. The results suggest that enhanced orexinergic signaling contributes to sympathetic overactivity and hypertension during the dark period in BPH/2J mice.
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Affiliation(s)
- Kristy L Jackson
- From the Neuropharmacology Laboratory, Baker IDI Heart and Diabetes Research Institute, Melbourne, Victoria, Australia (K.L.J., J.-L.M., E.R.S., P.J.D., G.A.H.); Blood Pressure, Brain and Behavior Laboratory, School of Medical Sciences, University of New South Wales, Sydney, New South Wales, Australia (B.W.D., P.C.); and Department of Pharmacology, Monash University, Melbourne, Victoria, Australia (G.A.H.)
| | - Bruno W Dampney
- From the Neuropharmacology Laboratory, Baker IDI Heart and Diabetes Research Institute, Melbourne, Victoria, Australia (K.L.J., J.-L.M., E.R.S., P.J.D., G.A.H.); Blood Pressure, Brain and Behavior Laboratory, School of Medical Sciences, University of New South Wales, Sydney, New South Wales, Australia (B.W.D., P.C.); and Department of Pharmacology, Monash University, Melbourne, Victoria, Australia (G.A.H.)
| | - John-Luis Moretti
- From the Neuropharmacology Laboratory, Baker IDI Heart and Diabetes Research Institute, Melbourne, Victoria, Australia (K.L.J., J.-L.M., E.R.S., P.J.D., G.A.H.); Blood Pressure, Brain and Behavior Laboratory, School of Medical Sciences, University of New South Wales, Sydney, New South Wales, Australia (B.W.D., P.C.); and Department of Pharmacology, Monash University, Melbourne, Victoria, Australia (G.A.H.)
| | - Emily R Stevenson
- From the Neuropharmacology Laboratory, Baker IDI Heart and Diabetes Research Institute, Melbourne, Victoria, Australia (K.L.J., J.-L.M., E.R.S., P.J.D., G.A.H.); Blood Pressure, Brain and Behavior Laboratory, School of Medical Sciences, University of New South Wales, Sydney, New South Wales, Australia (B.W.D., P.C.); and Department of Pharmacology, Monash University, Melbourne, Victoria, Australia (G.A.H.)
| | - Pamela J Davern
- From the Neuropharmacology Laboratory, Baker IDI Heart and Diabetes Research Institute, Melbourne, Victoria, Australia (K.L.J., J.-L.M., E.R.S., P.J.D., G.A.H.); Blood Pressure, Brain and Behavior Laboratory, School of Medical Sciences, University of New South Wales, Sydney, New South Wales, Australia (B.W.D., P.C.); and Department of Pharmacology, Monash University, Melbourne, Victoria, Australia (G.A.H.)
| | - Pascal Carrive
- From the Neuropharmacology Laboratory, Baker IDI Heart and Diabetes Research Institute, Melbourne, Victoria, Australia (K.L.J., J.-L.M., E.R.S., P.J.D., G.A.H.); Blood Pressure, Brain and Behavior Laboratory, School of Medical Sciences, University of New South Wales, Sydney, New South Wales, Australia (B.W.D., P.C.); and Department of Pharmacology, Monash University, Melbourne, Victoria, Australia (G.A.H.)
| | - Geoffrey A Head
- From the Neuropharmacology Laboratory, Baker IDI Heart and Diabetes Research Institute, Melbourne, Victoria, Australia (K.L.J., J.-L.M., E.R.S., P.J.D., G.A.H.); Blood Pressure, Brain and Behavior Laboratory, School of Medical Sciences, University of New South Wales, Sydney, New South Wales, Australia (B.W.D., P.C.); and Department of Pharmacology, Monash University, Melbourne, Victoria, Australia (G.A.H.).
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Morris BJ, Dampney RAL. Brain-stem microRNAs implicated in hypertension. Physiol Genomics 2015; 47:386-7. [PMID: 26242934 DOI: 10.1152/physiolgenomics.00079.2015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Affiliation(s)
- Brian J Morris
- Discipline of Physiology, School of Medical Sciences and Bosch Institute, University of Sydney, Sydney, New South Wales, Australia
| | - Roger A L Dampney
- Discipline of Physiology, School of Medical Sciences and Bosch Institute, University of Sydney, Sydney, New South Wales, Australia
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Morris BJ. Renin, genes, microRNAs, and renal mechanisms involved in hypertension. Hypertension 2015; 65:956-62. [PMID: 25601934 DOI: 10.1161/hypertensionaha.114.04366] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2014] [Accepted: 12/23/2014] [Indexed: 12/20/2022]
Affiliation(s)
- Brian J Morris
- From the Basic & Clinical Genomics Laboratory, School of Medical Sciences and Bosch Institute, The University of Sydney, Sydney, New South Wales, Australia.
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Abstract
In this review we focus on the role of orexin in cardio-respiratory functions and its potential link to hypertension. (1) Orexin, cardiovascular function, and hypertension. In normal rats, central administration of orexin can induce significant increases in arterial blood pressure (ABP) and sympathetic nerve activity (SNA), which can be blocked by orexin receptor antagonists. In spontaneously hypertensive rats (SHRs), antagonizing orexin receptors can significantly lower blood pressure under anesthetized or conscious conditions. (2) Orexin, respiratory function, and central chemoreception. The prepro-orexin knockout mouse has a significantly attenuated ventilatory CO2 chemoreflex, and in normal rats, central application of orexin stimulates breathing while blocking orexin receptors decreases the ventilatory CO2 chemoreflex. Interestingly, SHRs have a significantly increased ventilatory CO2 chemoreflex relative to normotensive WKY rats and blocking both orexin receptors can normalize this exaggerated response. (3) Orexin, central chemoreception, and hypertension. SHRs have higher ABP and SNA along with an enhanced ventilatory CO2 chemoreflex. Treating SHRs by blocking both orexin receptors with oral administration of an antagonist, almorexant (Almxt), can normalize the CO2 chemoreflex and significantly lower ABP and SNA. We interpret these results to suggest that the orexin system participates in the pathogenesis and maintenance of high blood pressure in SHRs, and the central chemoreflex may be a causal link to the increased SNA and ABP in SHRs. Modulation of the orexin system could be a potential target in treating some forms of hypertension.
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Affiliation(s)
- Aihua Li
- Department of Physiology and Neurobiology, Geisel School of Medicine at Dartmouth Lebanon, NH, USA
| | - Eugene Nattie
- Department of Physiology and Neurobiology, Geisel School of Medicine at Dartmouth Lebanon, NH, USA
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Li A, Nattie E. Orexin, cardio-respiratory function, and hypertension. Front Neurosci 2014; 8:22. [PMID: 24574958 PMCID: PMC3921571 DOI: 10.3389/fnins.2014.00022] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2013] [Accepted: 01/25/2014] [Indexed: 01/30/2023] Open
Abstract
In this review we focus on the role of orexin in cardio-respiratory functions and its potential link to hypertension. (1) Orexin, cardiovascular function, and hypertension. In normal rats, central administration of orexin can induce significant increases in arterial blood pressure (ABP) and sympathetic nerve activity (SNA), which can be blocked by orexin receptor antagonists. In spontaneously hypertensive rats (SHRs), antagonizing orexin receptors can significantly lower blood pressure under anesthetized or conscious conditions. (2) Orexin, respiratory function, and central chemoreception. The prepro-orexin knockout mouse has a significantly attenuated ventilatory CO2 chemoreflex, and in normal rats, central application of orexin stimulates breathing while blocking orexin receptors decreases the ventilatory CO2 chemoreflex. Interestingly, SHRs have a significantly increased ventilatory CO2 chemoreflex relative to normotensive WKY rats and blocking both orexin receptors can normalize this exaggerated response. (3) Orexin, central chemoreception, and hypertension. SHRs have higher ABP and SNA along with an enhanced ventilatory CO2 chemoreflex. Treating SHRs by blocking both orexin receptors with oral administration of an antagonist, almorexant (Almxt), can normalize the CO2 chemoreflex and significantly lower ABP and SNA. We interpret these results to suggest that the orexin system participates in the pathogenesis and maintenance of high blood pressure in SHRs, and the central chemoreflex may be a causal link to the increased SNA and ABP in SHRs. Modulation of the orexin system could be a potential target in treating some forms of hypertension.
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Affiliation(s)
- Aihua Li
- Department of Physiology and Neurobiology, Geisel School of Medicine at Dartmouth Lebanon, NH, USA
| | - Eugene Nattie
- Department of Physiology and Neurobiology, Geisel School of Medicine at Dartmouth Lebanon, NH, USA
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21
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GABAA receptor dysfunction contributes to high blood pressure and exaggerated response to stress in Schlager genetically hypertensive mice. J Hypertens 2014; 32:352-62. [DOI: 10.1097/hjh.0000000000000015] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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Druzd D, de Juan A, Scheiermann C. Circadian rhythms in leukocyte trafficking. Semin Immunopathol 2014; 36:149-62. [PMID: 24435096 DOI: 10.1007/s00281-013-0414-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2013] [Accepted: 12/02/2013] [Indexed: 11/28/2022]
Abstract
A broad range of immunological processes oscillates over the course of a day. Recent findings have identified a molecular basis for the circadian clock in the regulation of the immune system. These rhythms manifest themselves in oscillatory behavior of immune cells and proinflammatory mediators, which causes a time-dependent sensitivity in the reaction to pathogens. This rhythmicity impacts disease manifestations and severity and provides an option for therapy that incorporates chronopharmacological considerations. This review will focus on the current knowledge and relevance of rhythmic immune cell trafficking. It will provide an overview of the molecular clock machinery and its interrelations with leukocyte migration and the immune response.
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Affiliation(s)
- David Druzd
- Walter-Brendel-Center of Experimental Medicine, Ludwig-Maximilians-Universität München, Marchioninistraße 27, 81377, Munich, Germany
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Marques FZ, Morris BJ. Neurogenic hypertension: revelations from genome-wide gene expression profiling. Curr Hypertens Rep 2013; 14:485-91. [PMID: 22639016 DOI: 10.1007/s11906-012-0282-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
There is now good evidence for a role of the sympathetic nervous system in the etiology of essential hypertension in humans. Although genetic variation is expected to underlie the elevated sympathetic outflow in this complex polygenic condition, only limited information has emerged from classic molecular genetic studies. Recently, progress has been made in understanding neurogenic aspects by determination of global alterations in gene expression in key brain regions of animal models of neurogenic hypertension. Such genome-wide expression studies in the hypothalamus and brainstem support roles for factors such as neuronal nitric oxide synthase, inflammation and reactive oxygen species. A role for non-coding RNAs such as microRNAs, and epigenetic alterations await exploration. Ongoing novel approaches should provide a better understanding of the processes responsible for the increased sympathetic outflow in animal models, as well as essential hypertension in humans. Such information may lead to better therapies for neurogenic hypertension in humans.
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Han Y, Sun HJ, Li P, Gao Q, Zhou YB, Zhang F, Gao XY, Zhu GQ. Angiotensin-(1-7) in paraventricular nucleus modulates sympathetic activity and cardiac sympathetic afferent reflex in renovascular hypertensive rats. PLoS One 2012; 7:e48966. [PMID: 23139827 PMCID: PMC3489789 DOI: 10.1371/journal.pone.0048966] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2012] [Accepted: 10/01/2012] [Indexed: 12/14/2022] Open
Abstract
Background Excessive sympathetic activity contributes to the pathogenesis and progression of hypertension. Enhanced cardiac sympathetic afferent reflex (CSAR) is involved in sympathetic activation. This study was designed to determine the roles of angiotensin (Ang)-(1–7) in paraventricular nucleus (PVN) in modulating sympathetic activity and CSAR and its signal pathway in renovascular hypertension. Methodology/Principal Findings Renovascular hypertension was induced with two-kidney, one-clip method. Renal sympathetic nerve activity (RSNA) and mean arterial pressure (MAP) were recorded in sinoaortic-denervated and cervical-vagotomized rats with anesthesia. CSAR was evaluated with the RSNA and MAP responses to epicardial application of capsaicin. PVN microinjection of Ang-(1–7) and cAMP analogue db-cAMP caused greater increases in RSNA and MAP, and enhancement in CSAR in hypertensive rats than in sham-operated rats, while Mas receptor antagonist A-779 produced opposite effects. There was no significant difference in the angiotensin-converting enzyme 2 (ACE2) activity and Ang-(1–7) level in the PVN between sham-operated rats and hypertensive rats, but the Mas receptor protein expression in the PVN was increased in hypertensive rats. The effects of Ang-(1–7) were abolished by A-779, adenylyl cyclase inhibitor SQ22536 or protein kinase A (PKA) inhibitor Rp-cAMP. SQ22536 or Rp-cAMP reduced RSNA and MAP in hypertensive rats, and attenuated the CSAR in both sham-operated and hypertensive rats. Conclusions Ang-(1–7) in the PVN increases RSNA and MAP and enhances the CSAR, which is mediated by Mas receptors. Endogenous Ang-(1–7) and Mas receptors contribute to the enhanced sympathetic outflow and CSAR in renovascular hypertension. A cAMP-PKA pathway is involved in the effects of Ang-(1–7) in the PVN.
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Affiliation(s)
- Ying Han
- Key Laboratory of Cardiovascular Disease and Molecular Intervention, Department of Physiology, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Hai-Jian Sun
- Key Laboratory of Cardiovascular Disease and Molecular Intervention, Department of Physiology, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Peng Li
- Key Laboratory of Cardiovascular Disease and Molecular Intervention, Department of Physiology, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Qing Gao
- Key Laboratory of Cardiovascular Disease and Molecular Intervention, Department of Physiology, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Ye-bo Zhou
- Key Laboratory of Cardiovascular Disease and Molecular Intervention, Department of Physiology, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Feng Zhang
- Key Laboratory of Cardiovascular Disease and Molecular Intervention, Department of Physiology, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Xing-Ya Gao
- Key Laboratory of Cardiovascular Disease and Molecular Intervention, Department of Physiology, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Guo-Qing Zhu
- Key Laboratory of Cardiovascular Disease and Molecular Intervention, Department of Physiology, Nanjing Medical University, Nanjing, Jiangsu, China
- * E-mail:
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Manfredini R, Boari B, Salmi R, Fabbian F, Pala M, Tiseo R, Portaluppi F. Twenty-four-hour patterns in occurrence and pathophysiology of acute cardiovascular events and ischemic heart disease. Chronobiol Int 2012; 30:6-16. [PMID: 23002808 DOI: 10.3109/07420528.2012.715843] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The scientific literature clearly establishes the occurrence of cardiovascular (CV) accidents and myocardial ischemic episodes is unevenly distributed during the 24 h. Such temporal patterns result from corresponding temporal variation in pathophysiologic mechanisms and cyclic environmental triggers that elicit the onset of clinical events. Moreover, both the pharmacokinetics and pharmacodynamics of many, though not all, CV medications have been shown to be influenced by the circadian time of their administration, even though further studies are necessary to better clarify the mechanisms of such influence on different drug classes, drug molecules, and pharmaceutical preparations. Twenty-four-hour rhythmic organization of CV functions is such that defense mechanisms against acute events are incapable of providing the same degree of protection during the day and night. Instead, temporal gates of excessive susceptibility exist, particularly in the morning and to a lesser extent evening (in diurnally active persons), to aggressive mechanisms through which overt clinical manifestations may be triggered. When peak levels of critical physiologic variables, such as blood pressure (BP), heart rate (HR), rate pressure product (systolic BP × HR, surrogate measure of myocardial oxygen demand), sympathetic activation, and plasma levels of endogenous vasoconstricting substances, are aligned together at the same circadian time, the risk of acute events becomes significantly elevated such that even relatively minor and usually harmless physical and mental stress and environmental phenomena can precipitate dramatic life-threatening clinical manifestations. Hence, the delivery of CV medications needs to be synchronized in time, i.e., circadian time, in proportion to need as determined by established temporal patterns in risk of CV events, and in a manner that averts or minimizes undesired side effects.
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Affiliation(s)
- Roberto Manfredini
- Section of Clinica Medica, Department of Clinical and Experimental Medicine, University of Ferrara, Via Savonarola 9, Ferrara, Italy
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