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Bernardo EM, Pedroza AADS, Ferreira DJS, de Andrade SC, Rozendo A, Fernandes MSDS, Silva TL, Fernandes MP, Lagranha CJ. The deleterious effects of maternal protein deprivation on the brainstem are minimized with moderate physical activity by offspring during early life. Appl Physiol Nutr Metab 2024; 49:157-166. [PMID: 37816257 DOI: 10.1139/apnm-2023-0122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/12/2023]
Abstract
Maternal protein malnutrition during developmental periods might impair the redox state and the brain's excitatory/inhibitory neural network, increasing central sympathetic tone. Conversely, moderate physical exercise at an early age reduces the risk of chronic diseases. Thus, we hypothesized that a moderate training protocol could reduce the harmful effects of a low-protein maternal diet on the brainstem of young male offspring. We used a rat model of maternal protein restriction during the gestational and lactation period followed by an offspring's continuous treadmill exercise. Pregnant rats were divided into two groups according to the protein content in the diet: normoprotein (NP), receiving 17% of casein, and low protein (LP), receiving 8% of casein until the end of lactation. At 30 days of age, the male offspring were further subdivided into sedentary (NP-Sed and LP-Sed) or exercised (NP-Ex and LP-Ex) groups. Treadmill exercise was performed as follows: 4 weeks, 5 days/week, 60 min/day at 50% of maximal running capacity. The trained animals performed a treadmill exercise at 50% of the maximal running capacity, 60 min/day, 5 days/week, for 4 weeks. Our results indicate that a low-protein diet promotes deficits in the antioxidant system and a likely mitochondrial uncoupling. On the other hand, physical exercise restores the redox balance, which leads to decreased oxidative stress caused by the diet. In addition, it also promotes benefits to GABAergic inhibitory signaling. We conclude that regular moderate physical exercise performed in youthhood protects the brainstem against changes induced by maternal protein restriction.
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Affiliation(s)
| | | | | | - Severina Cassia de Andrade
- Neuropsyquiatry and Behavioral Science Graduate Program, Federal University of Pernambuco (UFPE), Recife, Pernambuco, Brazil
| | - Allifer Rozendo
- Laboratory of Biochemistry and Exercise Biochemistry/CAV, Federal University of Pernambuco, Vitoria de Santo Antao, PE, Brazil
| | | | - Tercya Lucidi Silva
- Neuropsyquiatry and Behavioral Science Graduate Program, Federal University of Pernambuco (UFPE), Recife, Pernambuco, Brazil
| | - Mariana Pinheiro Fernandes
- Laboratory of Biochemistry and Exercise Biochemistry/CAV, Federal University of Pernambuco, Vitoria de Santo Antao, PE, Brazil
| | - Claudia J Lagranha
- Biochemistry and Physiology Graduate Program, Federal University of Pernambuco, Recife, PE, Brazil
- Neuropsyquiatry and Behavioral Science Graduate Program, Federal University of Pernambuco (UFPE), Recife, Pernambuco, Brazil
- Laboratory of Biochemistry and Exercise Biochemistry/CAV, Federal University of Pernambuco, Vitoria de Santo Antao, PE, Brazil
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Marques SM, Melo MR, Zoccal DB, Menani JV, Colombari DSA, Ferreira-Neto ML, Xavier CH, Colombari E, Pedrino GR. Acute inhibition of nicotinamide adenine dinucleotide phosphate oxidase in the commissural nucleus of the solitary tract reduces arterial pressure and renal sympathetic nerve activity in renovascular hypertension. J Hypertens 2023; 41:1634-1644. [PMID: 37466439 DOI: 10.1097/hjh.0000000000003516] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/20/2023]
Abstract
BACKGROUND A growing body of evidence suggests that oxidative stress plays a role in the pathophysiology of hypertension. However, the involvement of the reactive oxygen species (ROS) in the commissural nucleus of the solitary tract (commNTS) in development the of hypertension remains unclear. METHOD We evaluated the hemodynamic and sympathetic responses to acute inhibition of NADPH oxidase in the commNTS in renovascular hypertensive rats. Under anesthesia, male Holtzman rats were implanted with a silver clip around the left renal artery to induce 2-kidney 1-clip (2K1C) hypertension. After six weeks, these rats were anesthetized and instrumented for recording mean arterial pressure (MAP), renal blood flow (RBF), renal vascular resistance (RVR), and renal sympathetic nerve activity (RSNA) during baseline and after injection of apocynin (nicotinamide adenine dinucleotide phosphate oxidase inhibitor), NSC 23766 (RAC inhibitor) or saline into the commNTS. RESULTS Apocynin into the commNTS decreased MAP, RSNA, and RVR in 2K1C rats. NSC 23766 into the commNTS decreased MAP and RSNA, without changing RVR in 2K1C rats. CONCLUSION These results demonstrate that the formation of ROS in the commNTS is important to maintain sympathoexcitation and hypertension in 2K1C rats and suggest that NADPH oxidase in the commNTS could be a potential target for therapeutics in renovascular hypertension.
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Affiliation(s)
- Stefanne M Marques
- Center for Neuroscience and Cardiovascular Research, Federal University of Goias, Goiania, GO
- Department of Physiology and Pathology, School of Dentistry, São Paulo State University (UNESP), Araraquara, Brazil
| | - Mariana R Melo
- Department of Physiology and Pathology, School of Dentistry, São Paulo State University (UNESP), Araraquara, Brazil
- Department of Physiology, University of Melbourne, Parkville, VIC, Australia
| | - Daniel B Zoccal
- Department of Physiology and Pathology, School of Dentistry, São Paulo State University (UNESP), Araraquara, Brazil
| | - José V Menani
- Department of Physiology and Pathology, School of Dentistry, São Paulo State University (UNESP), Araraquara, Brazil
| | - Débora S A Colombari
- Department of Physiology and Pathology, School of Dentistry, São Paulo State University (UNESP), Araraquara, Brazil
| | - Marcos L Ferreira-Neto
- Department of Physiology, Institute of Biomedical Sciences, Federal University of Uberlândia, Uberlândia
| | - Carlos H Xavier
- Systems Neurobiology Laboratory. Department of Physiological Sciences, Institute of Biological Science, Federal University of Goias, Goiania, GO, Brazil
| | - Eduardo Colombari
- Department of Physiology and Pathology, School of Dentistry, São Paulo State University (UNESP), Araraquara, Brazil
| | - Gustavo R Pedrino
- Center for Neuroscience and Cardiovascular Research, Federal University of Goias, Goiania, GO
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Ehlen JC, Forman CM, Ostrowski D, Ostrowski TD. Autonomic Dysfunction Impairs Baroreflex Function in an Alzheimer's Disease Animal Model. J Alzheimers Dis 2022; 90:1449-1464. [PMID: 36278348 PMCID: PMC9742304 DOI: 10.3233/jad-220496] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
BACKGROUND Alzheimer's disease (AD) patients frequently present with orthostatic hypotension. This inability to reflexively increase blood pressure on standing is a serious health concern and increases the risk of stroke and cardiovascular diseases. OBJECTIVE Since there are no clear mechanisms for orthostatic hypotension in human AD, the present study assessed the autonomic changes that could explain this comorbidity in an AD animal model. METHODS We used the established streptozotocin-induced rat model of AD (STZ-AD), which mimics many hallmark symptoms of sporadic AD in humans. Baroreflex responses were analyzed in anesthetized STZ-AD rats using femoral catheterization for blood pressure and heart rate, and autonomic activity was assessed using specific blockers and splanchnic sympathetic nerve recordings. Expression levels of autonomic receptors at the heart were examined using the western blot technique. RESULTS Baroreflex function in STZ-AD showed a blunted heart rate (HR) response to low blood pressure challenges, and the maximal sympathetic nerve activity was reduced. Conversely, HR responses to high blood pressure were similar to control, indicating no change in parasympathetic nerve activity. Under resting conditions, autonomic blockade demonstrated a baseline shift to increased sympathetic tone in STZ-AD. Protein expression levels of beta-1 adrenergic receptor and muscarinic acetylcholine receptor M2 in the heart were unchanged. CONCLUSION Our study provides the first data on the pathological influence of AD on baroreflex function, which primarily affected the sympathetic nervous system in STZ-AD. These results represent the first mechanisms that may correlate with the orthostatic hypotension in human AD.
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Affiliation(s)
- John C. Ehlen
- Department of Physiology, Kirksville College of Osteopathic Medicine, A.T. Still University of Health Sciences, Kirksville, MO, USA
| | | | | | - Tim D. Ostrowski
- Department of Physiology, Kirksville College of Osteopathic Medicine, A.T. Still University of Health Sciences, Kirksville, MO, USA
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Lauar MR, Colombari DSA, Colombari E, De Paula PM, De Luca LA, Menani JV. Catalase blockade reduces the pressor response to central cholinergic activation. Brain Res Bull 2019; 153:266-272. [PMID: 31545999 DOI: 10.1016/j.brainresbull.2019.09.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Revised: 09/16/2019] [Accepted: 09/18/2019] [Indexed: 02/06/2023]
Abstract
Intracerebroventricular (icv) injection of hydrogen peroxide (H2O2), a reactive oxygen species, or the blockade of catalase (enzyme that degrades H2O2 into H2O and O2) with icv injection of 3-amino-1,2,4-triazole (ATZ) reduces the pressor effects of angiotensin II also injected icv. In the present study, we investigated the effects of ATZ injected icv or intravenously (iv) on the pressor responses induced by icv injections of the cholinergic agonist carbachol, which similar to angiotensin II induces pressor responses that depend on sympathoexcitation and vasopressin release. In addition, the effects of H2O2 icv on the pressor responses to icv carbachol were also tested to compare with the effects of ATZ. Normotensive non-anesthetized male Holtzman rats (280-300 g, n = 8-9/group) with stainless steel cannulas implanted in the lateral ventricle were used. Previous injection of ATZ (5 nmol/1 μl) or H2O2 (5 μmol/1 μl) icv similarly reduced the pressor responses induced by carbachol (4 nmol/1 μl) injected icv (13 ± 4 and 12 ± 4 mmHg, respectively, vs. vehicle + carbachol: 30 ± 5 mmHg). ATZ (3.6 mmol/kg of body weight) injected iv also reduced icv carbachol-induced pressor responses (21 ± 2 mmHg). ATZ icv or iv and H2O2 icv injected alone produced no effect on baseline arterial pressure. The treatments also produced no significant change of heart rate. The results show that ATZ icv or iv reduced the pressor responses to icv carbachol, suggesting that endogenous H2O2 acting centrally inhibits the pressor mechanisms (sympathoactivation and/or vasopressin release) activated by central cholinergic stimulation.
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Affiliation(s)
- Mariana R Lauar
- Department of Physiology and Pathology, Dentistry School, São Paulo State University (UNESP), Araraquara, SP, Brazil
| | - Débora S A Colombari
- Department of Physiology and Pathology, Dentistry School, São Paulo State University (UNESP), Araraquara, SP, Brazil
| | - Eduardo Colombari
- Department of Physiology and Pathology, Dentistry School, São Paulo State University (UNESP), Araraquara, SP, Brazil
| | - Patrícia M De Paula
- Department of Physiology and Pathology, Dentistry School, São Paulo State University (UNESP), Araraquara, SP, Brazil
| | - Laurival A De Luca
- Department of Physiology and Pathology, Dentistry School, São Paulo State University (UNESP), Araraquara, SP, Brazil
| | - José V Menani
- Department of Physiology and Pathology, Dentistry School, São Paulo State University (UNESP), Araraquara, SP, Brazil.
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5
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Importance of AT1 and AT2 receptors in the nucleus of the solitary tract in cardiovascular responses induced by a high-fat diet. Hypertens Res 2019; 42:439-449. [PMID: 30631157 PMCID: PMC7092339 DOI: 10.1038/s41440-018-0196-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Revised: 06/27/2018] [Accepted: 07/26/2018] [Indexed: 02/01/2023]
Abstract
A high-fat diet (HFD) induces an increase in arterial pressure and a decrease in baroreflex function, which may be associated with increased expression of angiotensin type 1 receptor (AT1R) and pro-inflammatory cytokine genes and reduced expression of the angiotensin type 2 receptor (AT2R) gene within the nucleus of the solitary tract (NTS), a key area of the brainstem involved in cardiovascular control. Thus, in the present study, we evaluated the changes in arterial pressure and gene expression of components of the renin-angiotensin system (RAS) and neuroinflammatory markers in the NTS of rats fed a HFD and treated with either an AT1R blocker or with virus-mediated AT2R overexpression in the NTS. Male Holtzman rats (300-320 g) were fed either a standard rat chow diet (SD) or HFD for 6 weeks before commencing the tests. AT1R blockade in the NTS of HFD-fed rats attenuated the increase in arterial pressure and the impairment of reflex bradycardia, whereas AT2R overexpression in the NTS only improved the baroreflex function. The HFD also increased the hypertensive and decreased the protective axis of the RAS and was associated with neuroinflammation within the NTS. The expression of angiotensin-converting enzyme and neuroinflammatory components, but not AT1R, in the NTS was reduced by AT2R overexpression in this site. Based on these data, AT1R and AT2R in the NTS are differentially involved in the cardiovascular changes induced by a HFD. Chronic inflammation and changes in the RAS in the NTS may also account for the cardiovascular responses observed in HFD-fed rats.
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El-Mas MM, Abdel-Rahman AA. Role of Alcohol Oxidative Metabolism in Its Cardiovascular and Autonomic Effects. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1193:1-33. [PMID: 31368095 PMCID: PMC8034813 DOI: 10.1007/978-981-13-6260-6_1] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Several review articles have been published on the neurobehavioral actions of acetaldehyde and other ethanol metabolites as well as in major alcohol-related disorders such as cancer and liver and lung disease. However, very few reviews dealt with the role of alcohol metabolism in the adverse cardiac and autonomic effects of alcohol and their potential underlying mechanisms, particularly in vulnerable populations. In this chapter, following a brief overview of the dose-related favorable and adverse cardiovascular effects of alcohol, we discuss the role of ethanol metabolism in its adverse effects in the brainstem and heart. Notably, current knowledge dismisses a major role for acetaldehyde in the adverse autonomic and cardiac effects of alcohol because of its low tissue level in vivo. Contrary to these findings in men and male rodents, women and hypertensive individuals are more sensitive to the adverse cardiac effects of similar amounts of alcohol. To understand this discrepancy, we discuss the autonomic and cardiac effects of alcohol and its metabolite acetaldehyde in a model of hypertension, the spontaneously hypertensive rat (SHR) and female rats. We present evidence that enhanced catalase activity, which contributes to cardioprotection in hypertension (compensatory) and in the presence of estrogen (inherent), becomes detrimental due to catalase catalysis of alcohol metabolism to acetaldehyde. Noteworthy, studies in SHRs and in estrogen deprived or replete normotensive rats implicate acetaldehyde in triggering oxidative stress in autonomic nuclei and the heart via (i) the Akt/extracellular signal-regulated kinases (ERK)/nitric oxide synthase (NOS) cascade and (ii) estrogen receptor-alpha (ERα) mediation of the higher catalase activity, which generates higher ethanol-derived acetaldehyde in female heart. The latter is supported by the ability of ERα blockade or catalase inhibition to attenuate alcohol-evoked myocardial oxidative stress and dysfunction. More mechanistic studies are needed to further understand the mechanisms of this public health problem.
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Affiliation(s)
- Mahmoud M El-Mas
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Alexandria University, Alexandria, Egypt
| | - Abdel A Abdel-Rahman
- Department of Pharmacology and Toxicology, The Brody School of Medicine, East Carolina University, Greenville, NC, USA.
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7
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Sá JM, Barros MC, Melo MR, Colombari E, Menani JV, Colombari DSA. Endogenous hydrogen peroxide affects antidiuresis to cholinergic activation in the medial septal area. Neurosci Lett 2018; 694:51-56. [PMID: 30448293 DOI: 10.1016/j.neulet.2018.11.023] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2018] [Revised: 10/29/2018] [Accepted: 11/15/2018] [Indexed: 02/04/2023]
Abstract
Cholinergic activation of the medial septal area (MSA) with carbachol produces thirst, natriuresis and antidiuresis. Hydrogen peroxide (H2O2) injected into the medial septal area (MSA) impairs behavioral and renal responses induced by carbachol at the same site, suggesting the exogenous H2O2 may modulate the responses to cholinergic activation in the MSA. In the present study, we investigated if the accumulation of endogenous H2O2 in the MSA after the injection of the catalase inhibitor 3-amino-1,2,4-triazole (ATZ) also affects cholinergic responses. In addition, the effects of the combination of ATZ with a non-effective dose of H2O2 in the MSA were also tested. Male Holtzman rats (280-320 g) with stainless steel cannulas implanted in the MSA were used. The treatment with ATZ (10 nmol) into the MSA partially reverted the antidiuretic effect of carbachol (10.5 ± 0.7, vs. saline + carbachol: 7.3 ± 0.6 ml/120 min), without changing carbachol-induced water intake (9.5 ± 1.9, vs. saline + carbachol: 10.7 ± 1.6 ml/60 min). The combination of a low dose of ATZ (2.5 nmol) with an ineffective dose of H2O2 (0.5 μmol) into the MSA reduced carbachol-induced thirst (7.5 ± 2.0, vs. saline + carbachol: 14.9 ± 1.2 ml/15 min) and reverted the antidiuresis (8.1 ± 1.1, vs. saline + carbachol: 5.3 ± 0.9 ml/120 min). Sodium and potassium excretion were not modified regardless the treatment. Although exogenous H2O2 injected in the MSA may affect most of the responses to cholinergic activation of the MSA, the antidiuresis is the response clearly modulated by endogenous H2O2.
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Affiliation(s)
- Jéssica Matheus Sá
- Department of Physiology and Pathology, School of Dentistry, UNESP - São Paulo State University, Araraquara, SP, Brazil
| | - Milena Cassolatti Barros
- Department of Physiology and Pathology, School of Dentistry, UNESP - São Paulo State University, Araraquara, SP, Brazil
| | - Mariana Rosso Melo
- Department of Physiology and Pathology, School of Dentistry, UNESP - São Paulo State University, Araraquara, SP, Brazil
| | - Eduardo Colombari
- Department of Physiology and Pathology, School of Dentistry, UNESP - São Paulo State University, Araraquara, SP, Brazil
| | - José Vanderlei Menani
- Department of Physiology and Pathology, School of Dentistry, UNESP - São Paulo State University, Araraquara, SP, Brazil
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Pardo-Peña K, Lorea-Hernández JJ, Camacho-Hernández NP, Ordaz B, Villasana-Salazar B, Morales-Villagrán A, Peña-Ortega F. Hydrogen peroxide extracellular concentration in the ventrolateral medulla and its increase in response to hypoxia in vitro: Possible role of microglia. Brain Res 2018; 1692:87-99. [DOI: 10.1016/j.brainres.2018.04.032] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Revised: 03/31/2018] [Accepted: 04/25/2018] [Indexed: 12/12/2022]
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Yao F, Abdel-Rahman AA. Combined Catalase and ADH Inhibition Ameliorates Ethanol-Induced Myocardial Dysfunction Despite Causing Oxidative Stress in Conscious Female Rats. Alcohol Clin Exp Res 2017; 41:1541-1550. [PMID: 28667748 DOI: 10.1111/acer.13442] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2017] [Accepted: 06/24/2017] [Indexed: 01/15/2023]
Abstract
BACKGROUND Ethanol (EtOH)-evoked oxidative stress, which contributes to myocardial dysfunction in proestrus rats, is mediated by increases in NADPH oxidase (Nox) activity, malondialdehyde (MDA), and ERK1/2 phosphorylation. Whether these biochemical responses, which are triggered by alcohol-derived acetaldehyde in noncardiac tissues, occur in proestrus rats' hearts remains unknown. Therefore, we elucidated the roles of alcohol dehydrogenase (ADH), cytochrome P4502E1 (CYP2E1), and catalase, which catalyze alcohol oxidation to acetaldehyde, in these alcohol-evoked biochemical and hemodynamic responses in proestrus rats. METHODS Conscious proestrus rats prepared for measurements of left ventricular (LV) function and blood pressure (BP) received EtOH (1.5 g/kg, intravenous [i.v.] infusion over 30 minutes) or saline 30 minutes after an ADH and CYP2E1 inhibitor, 4-methylpyrazole (4-MP) (82 mg/kg, intraperitoneal), a catalase inhibitor, 3-AT (0.5 g/kg, i.v.), their combination, or vehicle. LV function and BP were monitored for additional 60 minutes after EtOH or saline infusion before collecting the hearts for ex vivo measurements of LV reactive oxygen species (ROS), Nox activity, MDA, and ERK1/2 phosphorylation. RESULTS EtOH reduced LV function (dP/dtmax and LV developed pressure) and BP, and increased cardiac Nox activity, ROS and MDA levels, and ERK1/2 phosphorylation. Either inhibitor partially, and their combination significantly, attenuated these responses despite the substantially higher blood EtOH level, and the increased cardiac oxidative stress and reduced BP caused by 3-AT alone or with 4-MP. The inhibitors reduced cardiac MDA level and reversed EtOH effect on cardiac and plasma MDA. CONCLUSIONS EtOH oxidative metabolism plays a pivotal role in the EtOH-evoked LV oxidative stress and dysfunction in proestrus rats. Notably, catalase inhibition (3-AT) caused cardiac oxidative stress and hypotension.
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Affiliation(s)
- Fanrong Yao
- Department of Pharmacology & Toxicology (FY, AAA-R), Brody School of Medicine, East Carolina University, Greenville, North Carolina
| | - Abdel A Abdel-Rahman
- Department of Pharmacology & Toxicology (FY, AAA-R), Brody School of Medicine, East Carolina University, Greenville, North Carolina
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10
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Chronic high-sodium diet intake after weaning lead to neurogenic hypertension in adult Wistar rats. Sci Rep 2017; 7:5655. [PMID: 28720883 PMCID: PMC5515999 DOI: 10.1038/s41598-017-05984-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Accepted: 06/06/2017] [Indexed: 02/07/2023] Open
Abstract
In this study, we investigated some mechanisms involved in sodium-dependent hypertension of rats exposed to chronic salt (NaCl) intake from weaning until adult age. Weaned male Wistar rats were placed under high (0.90% w/w, HS) or regular (0.27% w/w, Cont) sodium diets for 12 weeks. Water consumption, urine output and sodium excretion were higher in HS rats compared to control. Blood pressure (BP) was directly measured by the arterial catheter and found 13.8% higher in HS vs Cont rats. Ganglionic blockade with hexamethonium caused greater fall in the BP of HS rats (33%), and central antagonism of AT1 receptors (losartan) microinjected into the lateral ventricle reduced BP level of HS, but not of Cont group. Heart rate variability analysis revealed sympathetic prevalence on modulation of the systolic interval. HS diet did not affect creatinine clearance. Kidney histological analysis revealed no significant change in renal corpuscle structure. Sodium and potassium concentrations in CSF were found higher in HS rats despite no change in plasma concentration of these ions. Taken together, data suggest that animals exposed to chronic salt intake to a level close to that reported for human' diet since weaning lead to hypertension, which appears to rely on sodium-driven neurogenic mechanisms.
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11
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Ostrowski TD, Dantzler HA, Polo-Parada L, Kline DD. H 2O 2 augments cytosolic calcium in nucleus tractus solitarii neurons via multiple voltage-gated calcium channels. Am J Physiol Cell Physiol 2017; 312:C651-C662. [PMID: 28274920 DOI: 10.1152/ajpcell.00195.2016] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Revised: 03/06/2017] [Accepted: 03/08/2017] [Indexed: 12/20/2022]
Abstract
Reactive oxygen species (ROS) play a profound role in cardiorespiratory function under normal physiological conditions and disease states. ROS can influence neuronal activity by altering various ion channels and transporters. Within the nucleus tractus solitarii (nTS), a vital brainstem area for cardiorespiratory control, hydrogen peroxide (H2O2) induces sustained hyperexcitability following an initial depression of neuronal activity. The mechanism(s) associated with the delayed hyperexcitability are unknown. Here we evaluate the effect(s) of H2O2 on cytosolic Ca2+ (via fura-2 imaging) and voltage-dependent calcium currents in dissociated rat nTS neurons. H2O2 perfusion (200 µM; 1 min) induced a delayed, slow, and moderate increase (~27%) in intracellular Ca2+ concentration ([Ca2+]i). The H2O2-mediated increase in [Ca2+]i prevailed during thapsigargin, excluding the endoplasmic reticulum as a Ca2+ source. The effect, however, was abolished by removal of extracellular Ca2+ or the addition of cadmium to the bath solution, suggesting voltage-gated Ca2+ channels (VGCCs) as targets for H2O2 modulation. Recording of the total voltage-dependent Ca2+ current confirmed H2O2 enhanced Ca2+ entry. Blocking VGCC L, N, and P/Q subtypes decreased the number of cells and their calcium currents that respond to H2O2 The number of responder cells to H2O2 also decreased in the presence of dithiothreitol, suggesting the actions of H2O2 were dependent on sulfhydryl oxidation. In summary, here, we have shown that H2O2 increases [Ca2+]i and its Ca2+ currents, which is dependent on multiple VGCCs likely by oxidation of sulfhydryl groups. These processes presumably contribute to the previously observed delayed hyperexcitability of nTS neurons in in vitro brainstem slices.
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Affiliation(s)
- Tim D Ostrowski
- Department of Physiology, Kirksville College of Osteopathic Medicine, A.T. Still University of Health Sciences, Kirksville, Missouri.,Department of Biomedical Sciences, Dalton Cardiovascular Research Center, University of Missouri, Columbia, Missouri
| | - Heather A Dantzler
- Department of Biomedical Sciences, Dalton Cardiovascular Research Center, University of Missouri, Columbia, Missouri
| | - Luis Polo-Parada
- Department of Medical Pharmacology and Physiology, Dalton Cardiovascular Research Center, University of Missouri, Columbia, Missouri; and
| | - David D Kline
- Department of Biomedical Sciences, Dalton Cardiovascular Research Center, University of Missouri, Columbia, Missouri
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12
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Granato ÁS, Gomes PM, Martins Sá RW, Borges GSM, Alzamora AC, de Oliveira LB, Toney GM, Cardoso LM. Cardiovascular responses to l-glutamate microinjection into the NTS are abrogated by reduced glutathione. Neurosci Lett 2017; 642:142-147. [PMID: 28189741 DOI: 10.1016/j.neulet.2017.02.019] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Revised: 02/06/2017] [Accepted: 02/07/2017] [Indexed: 11/15/2022]
Abstract
Redox imbalance in regions of the CNS controlling blood pressure is increasingly recognized as a leading factor for hypertension. Nucleus tractus solitarius (NTS) of the dorsomedial medulla is the main region receiving excitatory visceral sensory inputs that modulate autonomic efferent drive to the cardiovascular system. This study sought to determine the capacity of reduced glutathione, a major bioactive antioxidant, to modulate NTS-mediated control of cardiovascular function in unanaesthetized rats. Male Fischer 344 rats were used for microinjection experiments. Cardiovascular responses to l-glutamate were first used to verify accurate placement of injections into the dorsomedial region comprising the NTS. Next, responses to GSH or vehicle were recorded followed by responses to l-glutamate again at the same site. GSH microinjection increased mean arterial pressure (MAP) compared to vehicle and abrogated responses to subsequent injection of l-glutamate. These data indicate that GSH microinjection into the NTS affects blood pressure regulation by dorsomedial neuronal circuits and blunts l-glutamate driven excitation in this region. These findings raise the possibility that increased antioxidant actions of GSH in NTS could contribute to autonomic control dysfunctions of the cardiovascular system.
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Affiliation(s)
- Álisson Silva Granato
- Federal University of Ouro Preto, Department of Biological Sciences/NUPEB, Campus Universitário Morro do Cruzeiro, Ouro Preto, MG, 35,400-000 Brazil
| | - Paula Magalhães Gomes
- Federal University of Ouro Preto, Department of Biological Sciences/NUPEB, Campus Universitário Morro do Cruzeiro, Ouro Preto, MG, 35,400-000 Brazil
| | - Renato William Martins Sá
- Federal University of Ouro Preto, Department of Biological Sciences/NUPEB, Campus Universitário Morro do Cruzeiro, Ouro Preto, MG, 35,400-000 Brazil
| | - Gabriel Silva Marques Borges
- Federal University of Ouro Preto, Department of Biological Sciences/NUPEB, Campus Universitário Morro do Cruzeiro, Ouro Preto, MG, 35,400-000 Brazil
| | - Andréia Carvalho Alzamora
- Federal University of Ouro Preto, Department of Biological Sciences/NUPEB, Campus Universitário Morro do Cruzeiro, Ouro Preto, MG, 35,400-000 Brazil
| | - Lisandra Brandino de Oliveira
- Federal University of Ouro Preto, Department of Biological Sciences/NUPEB, Campus Universitário Morro do Cruzeiro, Ouro Preto, MG, 35,400-000 Brazil
| | - Glenn M Toney
- Department of Physiology, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229, USA
| | - Leonardo M Cardoso
- Federal University of Ouro Preto, Department of Biological Sciences/NUPEB, Campus Universitário Morro do Cruzeiro, Ouro Preto, MG, 35,400-000 Brazil.
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Protein undernutrition during development and oxidative impairment in the central nervous system (CNS): potential factors in the occurrence of metabolic syndrome and CNS disease. J Dev Orig Health Dis 2016; 7:513-524. [DOI: 10.1017/s2040174416000246] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Mitochondria play a regulatory role in several essential cell processes including cell metabolism, calcium balance and cell viability. In recent years, it has been postulated that mitochondria participate in the pathogenesis of a number of chronic diseases, including central nervous system disorders. Thus, the concept of mitochondrial function now extends far beyond the common view of this organelle as the ‘powerhouse’ of the cell to a new appreciation of the mitochondrion as a transducer of early metabolic insult into chronic disease in later life. In this review, we have attempted to describe some of the associations between nutritional status and mitochondrial function (and dysfunction) during embryonic development with the occurrence of neural oxidative imbalance and neurogenic disease in adulthood.
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Zanella RC, Melo MR, Furuya WI, Colombari E, Menani JV, Colombari DSA. Hydrogen peroxide centrally attenuates hyperosmolarity-induced thirst and natriuresis. Neurosci Lett 2016; 610:129-34. [DOI: 10.1016/j.neulet.2015.10.067] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2015] [Revised: 10/14/2015] [Accepted: 10/27/2015] [Indexed: 11/25/2022]
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15
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Braz GRF, Pedroza AA, Nogueira VO, de Vasconcelos Barros MA, de Moura Freitas C, de Brito Alves JL, da Silva AI, Costa-Silva JH, Lagranha CJ. Serotonin modulation in neonatal age does not impair cardiovascular physiology in adult female rats: Hemodynamics and oxidative stress analysis. Life Sci 2016; 145:42-50. [DOI: 10.1016/j.lfs.2015.12.024] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2015] [Revised: 12/08/2015] [Accepted: 12/09/2015] [Indexed: 01/06/2023]
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Susac's Syndrome: A Case with Unusual Cardiac Vestibular and Imaging Manifestations. Case Rep Neurol Med 2015; 2015:419408. [PMID: 26688762 PMCID: PMC4673320 DOI: 10.1155/2015/419408] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2015] [Accepted: 11/18/2015] [Indexed: 11/18/2022] Open
Abstract
Susac's syndrome (SS) is a disease of the microvasculature of the retina, brain, and inner ear. We describe a patient with unusual manifestations of SS with possible involvement of the brainstem, cardiac arrhythmia, and MRI findings lacking the characteristic lesions found in Susac's syndrome.
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Ferreira DS, Liu Y, Fernandes MP, Lagranha CJ. Perinatal low-protein diet alters brainstem antioxidant metabolism in adult offspring. Nutr Neurosci 2015; 19:369-375. [PMID: 26035485 DOI: 10.1179/1476830515y.0000000030] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
BACKGROUND AND OBJECTIVES Studies in humans and animal models have established a close relationship between early environment insult and subsequent risk of development of non-communicable diseases, including the cardiovascular. Whereas experimental evidences highlight the early undernutrition and the late cardiovascular disease relation, the central mechanisms linking the two remain unknown. Owing to the oxidative balance influence in several pathologies, the aim of the present study was to evaluate the effects of maternal undernutrition (i.e. a low-protein (LP) diet) on oxidative balance in the brainstem. METHODS AND RESULTS Male rats from mothers fed with an LP diet (8% casein) throughout the perinatal period (i.e. gestation and lactation) showed 10× higher lipid peroxidation levels than animals treated with normoprotein (17% casein) at 100 days of age. In addition, we observed the following reductions in enzymatic activities: superoxide dismutase, 16%; catalase, 30%; glutathione peroxidase, 34%; glutathione-S-transferase, 51%; glutathione reductase, 23%; glucose-6-phosphate dehydrogenase, 31%; and in non-enzymatic glutathione system, 46%. DISCUSSION This study is the first to focus on the role of maternal LP nutrition in oxidative balance in a central nervous system structure responsible for cardiovascular control in adult rats. Our data observed changes in oxidative balance in the offspring, therefore, bring a new concept related to early undernutrition and can help in the development of a new clinical strategy to combat the effects of nutritional insult. Wherein the central oxidative imbalance is a feasible mechanism underlying the hypertension risk in adulthood triggered by maternal LP diet.
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Affiliation(s)
- Diorginis Soares Ferreira
- a Neuropsychiatry and Behavior Science Graduate Program , Federal University of Pernambuco , Vitória de Santo Antão 50670-901 , Brazil.,b Laboratory of Biochemistry and Exercise Biochemistry, Department of Physical Education and Sports Science , Federal University of Pernambuco-CAV , Vitória de Santo Antão 55608-680 , Brazil
| | - Yuri Liu
- b Laboratory of Biochemistry and Exercise Biochemistry, Department of Physical Education and Sports Science , Federal University of Pernambuco-CAV , Vitória de Santo Antão 55608-680 , Brazil
| | - Mariana Pinheiro Fernandes
- b Laboratory of Biochemistry and Exercise Biochemistry, Department of Physical Education and Sports Science , Federal University of Pernambuco-CAV , Vitória de Santo Antão 55608-680 , Brazil
| | - Claudia Jacques Lagranha
- a Neuropsychiatry and Behavior Science Graduate Program , Federal University of Pernambuco , Vitória de Santo Antão 50670-901 , Brazil.,b Laboratory of Biochemistry and Exercise Biochemistry, Department of Physical Education and Sports Science , Federal University of Pernambuco-CAV , Vitória de Santo Antão 55608-680 , Brazil
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18
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Franklin C, Fortepiani L, Nguyen T, Rangel Y, Strong R, Gottlieb HB. Renal responses produced by microinjection of the kappa opioid receptor agonist, U50-488H, into sites within the rat lamina terminalis. Pharmacol Res Perspect 2015; 3:e00117. [PMID: 26038693 PMCID: PMC4448977 DOI: 10.1002/prp2.117] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2014] [Revised: 11/18/2014] [Accepted: 11/24/2014] [Indexed: 01/01/2023] Open
Abstract
Activation of central kappa opioid receptors (KOR) has been demonstrated to produce marked free water diuresis with a concurrent increase in renal sympathetic nerve activity (RSNA). This study investigated the cardiovascular (CV) and renal effects evoked by central activation of KOR in two lamina terminalis sites, the median preoptic area (MPA) and anterolateral division of the bed nuclei of the stria terminalis (BST). Rats anesthetized with urethane alpha-chloralose were instrumented to record mean arterial pressure, heart rate, RSNA, and urine output (V). Rats were infused with isotonic saline (25 μL/min) and urine samples were collected during two 10-min control periods and six consecutive 10-min experimental periods following microinjection of vehicle, U50-448H (U50, KOR agonist) alone or norbinaltorphimine (nor-BNI, KOR antagonist) plus U50. Microinjection of U50 into the BST increased V (peak at 30 min, 84.8 ± 12.9 μL/min) as compared to its respective control, vehicle, or nor-BNI plus U50. This diuretic effect occurred without any significant changes in CV parameters, RSNA, or urinary sodium excretion. In contrast, U50 injection into the MPA significantly increased RSNA (peak at 20 mins: 129 ± 9.9) without increasing the other parameters. This study demonstrated novel sites through which activation of KOR selectively increases V and RSNA. The ability of U50 to increase V without affecting sodium excretion and RSNA raises the possibility that LT neurons could be an important substrate through which drugs targeting KOR could selectively facilitate water excretion in sodium-retaining diseases such as congestive heart failure.
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Affiliation(s)
- Cynthia Franklin
- Department of Pharmaceutical Sciences, Feik School of Pharmacy, University of Incarnate Word San Antonio, Texas, 78209
| | - Lourdes Fortepiani
- Rosenberg School of Optometry, University of Incarnate Word San Antonio, Texas, 78209
| | - Tin Nguyen
- Department of Pharmaceutical Sciences, Feik School of Pharmacy, University of Incarnate Word San Antonio, Texas, 78209
| | - Yolanda Rangel
- Department of Physical Therapy, University of Texas Health Science Center at San Antonio San Antonio, Texas, 78229
| | - Randy Strong
- Department of Pharmacology and the Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center at San Antonio and the South Texas Veterans Health Care System San Antonio, Texas, 78229
| | - Helmut B Gottlieb
- Department of Pharmaceutical Sciences, Feik School of Pharmacy, University of Incarnate Word San Antonio, Texas, 78209
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Ostrowski TD, Hasser EM, Heesch CM, Kline DD. H₂O₂ induces delayed hyperexcitability in nucleus tractus solitarii neurons. Neuroscience 2014; 262:53-69. [PMID: 24397952 DOI: 10.1016/j.neuroscience.2013.12.055] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2013] [Revised: 12/23/2013] [Accepted: 12/24/2013] [Indexed: 12/19/2022]
Abstract
Hydrogen peroxide (H₂O₂) is a stable reactive oxygen species and potent neuromodulator of cellular and synaptic activity. Centrally, endogenous H₂O₂ is elevated during bouts of hypoxia-reoxygenation, a variety of disease states, and aging. The nucleus tractus solitarii (nTS) is the central termination site of visceral afferents for homeostatic reflexes and contributes to reflex alterations during these conditions. We determined the extent to which H₂O₂ modulates synaptic and membrane properties in nTS neurons in rat brainstem slices. Stimulation of the tractus solitarii (which contains the sensory afferent fibers) evoked synaptic currents that were not altered by 10-500 μM H₂O₂. However, 500 μM H₂O₂ modulated several intrinsic membrane properties of nTS neurons, including a decrease in input resistance (R(i)), hyperpolarization of resting membrane potential (RMP) and action potential (AP) threshold (THR), and an initial reduction in AP discharge to depolarizing current. H₂O₂ increased conductance of barium-sensitive potassium currents, and block of these currents ablated H₂O₂-induced changes in RMP, Ri and AP discharge. Following washout of H₂O₂ AP discharge was enhanced due to depolarization of RMP and a partially maintained hyperpolarization of THR. Hyperexcitability persisted with repeated H₂O₂ exposure. H₂O₂ effects on RMP and THR were ablated by intracellular administration of the antioxidant catalase, which was immunohistochemically identified in neurons throughout the nTS. Thus, H₂O₂ initially reduces excitability of nTS neurons that is followed by sustained hyperexcitability, which may play a profound role in cardiorespiratory reflexes.
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Affiliation(s)
- T D Ostrowski
- Department of Biomedical Sciences, Dalton Cardiovascular Research Center, University of Missouri, Columbia, MO, USA
| | - E M Hasser
- Department of Biomedical Sciences, Dalton Cardiovascular Research Center, University of Missouri, Columbia, MO, USA
| | - C M Heesch
- Department of Biomedical Sciences, Dalton Cardiovascular Research Center, University of Missouri, Columbia, MO, USA
| | - D D Kline
- Department of Biomedical Sciences, Dalton Cardiovascular Research Center, University of Missouri, Columbia, MO, USA.
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Abstract
SIGNIFICANCE There is now compelling evidence to substantiate the notion that by depressing baroreflex regulation of blood pressure and augmenting central sympathetic outflow through their actions on the nucleus tractus solitarii (NTS) and rostral ventrolateral medulla (RVLM), brain stem nitric oxide synthase (NOS) and reactive oxygen species (ROS) are important contributing factors to neural mechanisms of hypertension. This review summarizes our contemporary views on the impact of NOS and ROS in the NTS and RVLM on neurogenic hypertension, and presents potential antihypertensive strategies that target brain stem NOS/ROS signaling. RECENT ADVANCES NO signaling in the brain stem may be pro- or antihypertensive depending on the NOS isoform that generates this gaseous moiety and the site of action. Elevation of the ROS level when its production overbalances its degradation in the NTS and RVLM underlies neurogenic hypertension. Interventional strategies with emphases on alleviating the adverse actions of these molecules on blood pressure regulation have been investigated. CRITICAL ISSUES The pathological roles of NOS in the RVLM and NTS in neural mechanisms of hypertension are highly complex. Likewise, multiple signaling pathways underlie the deleterious roles of brain-stem ROS in neurogenic hypertension. There are recent indications that interactions between brain stem ROS and NOS may play a contributory role. FUTURE DIRECTIONS Given the complicity of action mechanisms of brain-stem NOS and ROS in neural mechanisms of hypertension, additional studies are needed to identify the most crucial therapeutic target that is applicable not only in animal models but also in patients suffering from neurogenic hypertension.
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Affiliation(s)
- Samuel H H Chan
- Center for Translational Research in Biomedical Sciences, Kaohsiung Chang Gung Memorial Hospital , Kaohsiung, Taiwan, Republic of China
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21
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Kane AD, Herrera EA, Camm EJ, Giussani DA. Vitamin C prevents intrauterine programming of in vivo cardiovascular dysfunction in the rat. Circ J 2013; 77:2604-11. [PMID: 23856654 DOI: 10.1253/circj.cj-13-0311] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
BACKGROUND Fetal hypoxia is common and in vitro evidence supports its role in the programming of adult cardiovascular dysfunction through the generation of oxidative stress. Whether fetal chronic hypoxia programmes alterations in cardiovascular control in vivo, and if these alterations can be prevented by antioxidant treatment, is unknown. This study investigated the effects of prenatal fetal hypoxia, with and without maternal supplementation with vitamin C, on basal and stimulated cardiovascular function in vivo in the adult offspring at 4 months of age in the rat. METHODS AND RESULTS From days 6 to 20 of pregnancy, Wistar rats were subjected to Normoxia, Hypoxia (13% O2), Hypoxia+Vitamin C (5mg/ml in drinking water) or Normoxia+Vitamin C. At 4 months, male offspring were instrumented under urethane anaesthesia. Basal mean arterial blood pressure, heart rate and heart rate variability (HRV) were assessed, and stimulated baroreflex curves were generated with phenylephrine and sodium nitroprusside. Chronic fetal hypoxia increased the LF/HF HRV ratio and baroreflex gain, effects prevented by vitamin C administration during pregnancy. CONCLUSIONS Chronic intrauterine hypoxia programmes cardiovascular dysfunction in vivo in adult rat offspring; effects ameliorated by maternal treatment with vitamin C. The data support a role for fetal chronic hypoxia programming cardiovascular dysfunction in the adult rat offspring in vivo through the generation of oxidative stress in utero.
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Affiliation(s)
- Andrew D Kane
- Department of Physiology, Development and Neuroscience, University of Cambridge
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Gyanesh P, Haldar R. Hemodynamic derangements with hydrogen peroxide instillation in neurosurgery: need for awareness among anesthesiologists and surgeons. World Neurosurg 2012; 82:e388-9. [PMID: 23111214 DOI: 10.1016/j.wneu.2012.10.070] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2012] [Accepted: 10/25/2012] [Indexed: 11/25/2022]
Affiliation(s)
- Prakhar Gyanesh
- Department of Anesthesiology, Sanjay Gandhi Postgraduate Institute, Lucknow, India.
| | - Rudrashish Haldar
- Department of Anesthesiology, Sanjay Gandhi Postgraduate Institute, Lucknow, India
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Cardoso LM, Colombari E, Toney GM. Endogenous hydrogen peroxide in the hypothalamic paraventricular nucleus regulates sympathetic nerve activity responses to L-glutamate. J Appl Physiol (1985) 2012; 113:1423-31. [PMID: 22984242 DOI: 10.1152/japplphysiol.00912.2012] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The hypothalamic paraventricular nucleus (PVN) is important for maintenance of sympathetic nerve activity (SNA) and cardiovascular function. PVN-mediated increases of SNA often involve the excitatory amino acid L-glutamate (L-glu), whose actions can be positively and negatively modulated by a variety of factors, including reactive oxygen species. Here, we determined modulatory effects of the highly diffusible reactive oxygen species hydrogen peroxide (H(2)O(2)) on responses to PVN L-glu. Renal SNA (RSNA), arterial blood pressure, and heart rate were recorded in anesthetized rats. L-Glu (0.2 nmol in 100 nl) microinjected unilaterally into PVN increased RSNA (P < 0.05), without affecting mean arterial blood pressure or heart rate. Effects of endogenously generated H(2)O(2) were determined by comparing responses to PVN L-glu before and after PVN injection of the catalase inhibitor 3-amino-1,2,4-triazole (ATZ; 100 nmol/200 nl, n = 5). ATZ alone was without effect on recorded variables, but attenuated the increase of RSNA elicited by PVN L-glu (P < 0.05). PVN injection of exogenous H(2)O(2) (5 nmol in 100 nl, n = 4) and vehicle (artificial cerebrospinal fluid) were without affect, but H(2)O(2), like ATZ, attenuated the increase of RSNA to PVN L-glu (P < 0.05). Tonic effects of endogenous H(2)O(2) were determined by PVN injection of polyethylene glycol-catalase (1.0 IU in 200 nl, n = 5). Whereas polyethylene glycol-catalase alone was without effect, increases of RSNA to subsequent PVN injection of L-glu were increased (P < 0.05). From these data, we conclude that PVN H(2)O(2) tonically, but submaximally, suppresses RSNA responses to L-glu, supporting the idea that a change of H(2)O(2) availability within PVN could influence SNA regulation under physiological and/or disease conditions.
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Affiliation(s)
- Leonardo M Cardoso
- Department of Physiology, University of Texas Health Science Center at San Antonio, San Antonio, Texas 78229, USA
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Chan SHH, Chan JYH. Brain stem oxidative stress and its associated signaling in the regulation of sympathetic vasomotor tone. J Appl Physiol (1985) 2012; 113:1921-8. [PMID: 22837172 DOI: 10.1152/japplphysiol.00610.2012] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
There is now compelling evidence from studies in humans and animals that overexcitation of the sympathetic nervous system plays an important role in the pathogenesis of cardiovascular diseases. An excellent example is neurogenic hypertension, in which central sympathetic overactivation is involved in the development, staging, and progression of the disease, and one of the underlying mechanisms involves oxidative stress in key brain stem sites that are engaged in the regulation of sympathetic vasomotor tone. Using the rostral ventrolateral medulla (RVLM) and nucleus tractus solitarii (NTS) as two illustrative brain stem neural substrates, this article provides an overview of the impact of reactive oxygen species and antioxidants on RVLM and NTS in the pathogenesis of neurogenic hypertension. This is followed by a discussion of the redox-sensitive signaling pathways, including several kinases, ion channels, and transcription factors that underpin the augmentation in sympathetic vasomotor tone. In addition, the emerging view that brain stem oxidative stress is also causally related to a reduction in sympathetic vasomotor tone and hypotension during brain stem death, methamphetamine intoxication, and temporal lobe status epilepticus will be presented, along with the causal contribution of the oxidant peroxynitrite formed by a reaction between nitric oxide synthase II (NOS II)-derived nitric oxide and superoxide. Also discussed as a reasonable future research direction is dissection of the cellular mechanisms and signaling cascades that may underlie the contributory role of nitric oxide generated by different NOS isoforms in the differential effects of oxidative stress in the RVLM or NTS on sympathetic vasomotor tone.
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Affiliation(s)
- Samuel H H Chan
- Center for Translational Research in Biomedical Sciences, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan, Republic of China
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Cisternas JR, Valenti VE, Sato MA, Fonseca FLA, Saldiva PHN, De Mello Monteiro CB, Neto MLR, Rodrigues LMR, De Abreu LC. The effects of catalase inhibition into the fourth cerebral ventricle on the Bezold-Jarisch reflex in spontaneously hypertensive rats. J Integr Neurosci 2012; 10:475-87. [PMID: 22262536 DOI: 10.1142/s021963521100283x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2011] [Accepted: 09/19/2011] [Indexed: 11/18/2022] Open
Abstract
Many studies have investigated the role of oxidative stress on cardiovascular system in the brainstem of spontaneously hypertensive rats (SHR). However, we do not know yet if catalase inhibition influences cardiopulmonary reflex (Bezol-Jarisch reflex). Thus, we aimed to evaluate the effects of central catalase inhibition on cardiopulmonary reflex in SHR. Males Wistar Kyoto (WKY) rats and SHR were implanted with a stainless steel guide cannula into the fourth cerebral ventricle (4th V). The femoral artery and vein were cannulated for mean arterial pressure (MAP) and heart rate (HR) measurement and drug infusion, respectively. The cardiopulmonary reflex was tested with phenylbiguanide (PBG, 8 μg/kg, bolus, i.v.). Cardiopulmonary reflex was evaluated before and 15 minutes after 3-amino-1,2,4-triazole (ATZ, 0.01 g/100 μL) injection into the 4th V. Vehicle treatment did not change basal MAP and HR and cardiopulmonary reflex responses in SHR and WKY rats. Central ATZ increased hypotensive (p=0.038) responses without influencing the bradycardic reflex (p=0.287) in WKY rats. In SHR, ATZ increased hypotension (p=0.0004) and bradycardic (p=0.04) responses to i.v. PBG. No changes were observed regarding basal MAP and HR after ATZ injection in SHR and WKY rats. We suggest central catalase inhibition affects cardiopulmonary reflex with more intensity in SHR compared to WKY rats.
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Affiliation(s)
- José Raul Cisternas
- Laboratório de Escrita Científica, Departamento de Morfologia e Fisiologia, Faculdade de Medicina do ABC, Santo André, SP, Brazil.
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Valenti VE, de Abreu LC, Sato MA, Ferreira C, Adami F, Fonseca FLA, Xavier V, Godoy M, Monteiro CB, Vanderlei LCM, Saldiva PHN. Sidestream cigarette smoke effects on cardiovascular responses in conscious rats: involvement of oxidative stress in the fourth cerebral ventricle. BMC Cardiovasc Disord 2012; 12:22. [PMID: 22463380 PMCID: PMC3352042 DOI: 10.1186/1471-2261-12-22] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2011] [Accepted: 03/30/2012] [Indexed: 02/07/2023] Open
Abstract
Background Cigarette exposure increases brain oxidative stress. The literature showed that increased brain oxidative stress affects cardiovascular regulation. However, no previous study investigated the involvement of brain oxidative stress in animals exposed to cigarette and its relationship with cardiovascular regulation. We aimed to evaluate the effects of central catalase inhibition on baroreflex and cardiovascular responses in rats exposed to sidestream cigarette smoke (SSCS). Methods We evaluated males Wistar rats (320-370 g), which were implanted with a stainless steel guide cannula into the fourth cerebral ventricle (4th V). Femoral artery and vein were cannulated for mean arterial pressure (MAP) and heart rate (HR) measurement and drug infusion, respectively. Rats were exposed to SSCS during three weeks, 180 minutes, 5 days/week (CO: 100-300 ppm). Baroreflex was tested with a pressor dose of phenylephrine (PHE, 8 μg/kg, bolus) to induce bradycardic reflex and a depressor dose of sodium nitroprusside (SNP, 50 μg/kg, bolus) to induce tachycardic reflex. Cardiovascular responses were evaluated before, 5, 15, 30 and 60 minutes after 3-amino-1,2,4-triazole (ATZ, catalase inhibitor, 0.001 g/100 μL) injection into the 4th V. Results Central catalase inhibition increased basal HR in the control group during the first 5 minutes. SSCS exposure increased basal HR and attenuated bradycardic peak during the first 15 minutes. Conclusion We suggest that SSCS exposure affects cardiovascular regulation through its influence on catalase activity.
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Affiliation(s)
- Vitor E Valenti
- Programa de Pós-Graduação em Fisioterapia, Faculdade de Ciências e Tecnologia, Universidade Estadual Paulista, UNESP, Presidente Prudente, SP, Brazil.
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Valenti VE, De Abreu LC, Sato MA, Fonseca FLA, Riera ARP, Ferreira C. Catalase inhibition into the fourth cerebral ventricle affects bradycardic parasympathetic response to increase in arterial pressure without changing the baroreflex. J Integr Neurosci 2012; 10:1-14. [PMID: 21425479 DOI: 10.1142/s0219635211002580] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2010] [Accepted: 12/14/2010] [Indexed: 11/18/2022] Open
Abstract
Exogenous catalase influences neural control of cardiovascular system; however, we do not know yet if its inhibition into the fourth cerebral ventricle (4(th) V) influences baroreflex regulation. We evaluated the effects of central catalase inhibition on baroreflex in conscious Wistar rats. We used males Wistar rats (320-370 g), which were implanted with a stainless steel guide cannula into 4(th) V. The femoral artery and vein were cannulated for mean arterial pressure (MAP) and heart rate (HR) measurement and drug infusion, respectively. After basal MAP and HR recordings, the baroreflex was tested with a pressor dose of phenylephrine (PHE, 8 μg/kg, bolus) and a depressor dose of sodium nitroprusside (SNP, 50 μg/kg, bolus). Baroreflex was evaluated before 5, 15, 30 and 60 minutes after 3-amino-1, 2, 4-triazole (ATZ, 0.001 g/100 μL) injection into the 4(th) V. Vehicle treatment did not change baroreflex responses. ATZ attenuated bradycardic peak and reduced HR range at 30 minutes. ATZ into the 4(th) V reduced bradycardic and tachycardic reflex responses to increase and decrease MAP, respectively (p<0.05) 30 minutes after its microinjection without significantly changing the basal MAP and HR. In conclusion, central catalase inhibition influenced the highest parasympathetic response to MAP increase in conscious Wistar rats without change baroreflex gain.
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Affiliation(s)
- Vitor E Valenti
- Departamento de Medicina, Disciplina de Cardiologia, Universidade Federal de São Paulo (UNIFESP), Rua Napoleão de Barros, 715 - Térreo 04039-032 São Paulo, SP, Brasil.
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El-Mas MM, Abdel-Rahman AA. Enhanced catabolism to acetaldehyde in rostral ventrolateral medullary neurons accounts for the pressor effect of ethanol in spontaneously hypertensive rats. Am J Physiol Heart Circ Physiol 2012; 302:H837-44. [PMID: 22159996 PMCID: PMC3353783 DOI: 10.1152/ajpheart.00958.2011] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/28/2011] [Accepted: 12/01/2011] [Indexed: 11/22/2022]
Abstract
We have previously shown that ethanol microinjection into the rostral ventrolateral medulla (RVLM) elicits sympathoexcitation and hypertension in conscious spontaneously hypertensive rats (SHRs) but not in Wistar-Kyoto (WKY) rats. In this study, evidence was sought to implicate the oxidative breakdown of ethanol in this strain-dependent hypertensive action of ethanol. Biochemical experiments revealed significantly higher catalase activity and similar aldehyde dehydrogenase (ALDH) activity in the RVLM of SHRs compared with WKY rats. We also investigated the influence of pharmacological inhibition of catalase (3-aminotriazole) or ALDH (cyanamide) on the cardiovascular effects of intra-RVLM ethanol or its metabolic product acetaldehyde in conscious rats. Compared with vehicle, ethanol (10 μg/rat) elicited a significant increase in blood pressure in SHRs that lasted for the 60-min observation period but had no effect on blood pressure in WKY rats. The first oxidation product, acetaldehyde, played a critical role in ethanol-evoked hypertension because 1) catalase inhibition (3-aminotriazole treatment) virtually abolished the ethanol-evoked pressor response in SHRs, 2) intra-RVLM acetaldehyde (2 μg/rat) reproduced the strain-dependent hypertensive effect of intra-RVLM ethanol, and 3) ALDH inhibition (cyanamide treatment) uncovered a pressor response to intra-RVLM acetaldehyde in WKY rats similar to the response observed in SHRs. These findings support the hypothesis that local production of acetaldehyde, due to enhanced catalase activity, in the RVLM mediates the ethanol-evoked pressor response in SHRs.
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Affiliation(s)
- Mahmoud M El-Mas
- Department of Pharmacology and Toxicology, School of Medicine, East Carolina University, Greenville, NC 27834, USA.
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Abstract
Increasing evidence implicates hydrogen peroxide (H(2)O(2)) as an intracellular and intercellular signaling molecule that can influence processes from embryonic development to cell death. Most research has focused on relatively slow signaling, on the order of minutes to days, via second messenger cascades. However, H(2)O(2) can also mediate subsecond signaling via ion channel activation. This rapid signaling has been examined most thoroughly in the nigrostriatal dopamine (DA) pathway, which plays a key role in facilitating movement mediated by the basal ganglia. In DA neurons of the substantia nigra, endogenously generated H(2)O(2) activates ATP-sensitive K(+) (K-ATP) channels that inhibit DA neuron firing. In the striatum, H(2)O(2) generated downstream from glutamatergic AMPA receptor activation in medium spiny neurons acts as a diffusible messenger that inhibits axonal DA release, also via K-ATP channels. The source of dynamically generated H(2)O(2) is mitochondrial respiration; thus, H(2)O(2) provides a novel link between activity and metabolism via K-ATP channels. Additional targets of H(2)O(2) include transient receptor potential (TRP) channels. In contrast to the inhibitory effect of H(2)O(2) acting via K-ATP channels, TRP channel activation is excitatory. This review describes emerging roles of H(2)O(2) as a signaling agent in the nigrostriatal pathway and basal ganglia neurons.
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Affiliation(s)
- Margaret E Rice
- Department of Neurosurgery, New York University School of Medicine, New York, NY 10016, USA.
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Giusti MF, Sato MA, Cardoso LM, Braga VA, Colombari E. Central antioxidant therapy inhibits parasympathetic baroreflex control in conscious rats. Neurosci Lett 2011; 489:115-8. [DOI: 10.1016/j.neulet.2010.11.077] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2010] [Revised: 11/30/2010] [Accepted: 11/30/2010] [Indexed: 02/07/2023]
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Liu JQ, Lee TF, Chen C, Bagim DL, Cheung PY. N-acetylcysteine improves hemodynamics and reduces oxidative stress in the brains of newborn piglets with hypoxia-reoxygenation injury. J Neurotrauma 2011; 27:1865-73. [PMID: 20649480 DOI: 10.1089/neu.2010.1325] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Reactive oxygen species have been implicated in the pathogenesis of hypoxic-ischemic injury. It has been shown previously that treating an animal with N-acetyl-L-cysteine (NAC), a scavenger of free radicals, significantly minimizes hypoxic-ischemic-induced brain injury in various acute models. Using a subacute swine model of neonatal hypoxia-reoxygenation (H-R), we evaluated the long-term beneficial effect of NAC against oxidative stress-induced brain injury. Newborn piglets were randomly assigned to a sham-operated group (without H-R, n = 6), and two H-R experimental groups (n = 8 each), with 2 h normocapnic alveolar hypoxia and 1 h of 100% oxygen reoxygenation followed by 21% oxygen for 47 h. Five minutes after reoxygenation, the H-R piglets received either normal saline (H-R controls) or NAC (150 mg/kg bolus and 20 mg/kg/h IV for 24 h) in a blinded randomized fashion. Treating the piglets with NAC significantly increased both common carotid arterial flow (CCAF) and oxygen delivery during the early phase of rexoygenation, while both CCAF and carotid oxygen delivery of the H-R group remained lower than the sham-operated groups throughout the experimental period. Compared with H-R controls, significantly higher amounts of anesthetic and sedative medications were required to maintain the NAC-treated piglets in stable condition throughout the experimental period, indicating a stronger recovery. Post-resuscitation NAC treatment also significantly attenuated the increase in cortical caspase-3 and lipid hydroperoxide concentrations. Our findings suggest that post-resuscitation administration of NAC reduces cerebral oxidative stress with improved cerebral oxygen delivery, and probably attenuates apoptosis in newborn piglets with H-R insults.
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Affiliation(s)
- Jiang-Qin Liu
- Department of Pediatrics, University of Alberta, Edmonton, Alberta, Canada
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Mi L, Gan N, Chung FL. Isothiocyanates inhibit proteasome activity and proliferation of multiple myeloma cells. Carcinogenesis 2010; 32:216-23. [PMID: 21109604 DOI: 10.1093/carcin/bgq242] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Isothiocyanates (ITCs), including benzyl isothiocyanate (BITC), phenethyl isothiocyanate (PEITC) and sulforaphane, compounds found in cruciferous vegetable, are highly effective in inducing cell cycle arrest and apoptosis in a variety of cancer cells and animal models. Although some studies indicate that ITC-induced reactive oxygen species (ROS) generation may underlie apoptosis induction, our recent studies show that covalent binding to target proteins may be an important event triggering apoptosis. In this study, we report that BITC and PEITC significantly inhibit proteasome activity in a variety of cell types. Further studies show that ITCs inhibit both the 26S and 20S proteasomes, presumably through direct binding, and that this inhibition is unrelated to either ROS generation or ITC-induced protein aggregation. The potency of ITC-induced proteasome inhibition correlates with the rapid accumulation of p53 (tumor suppressor) and IκB nuclear factor-kappaB (nuclear factor-kappaB inhibitor). Finally, our results demonstrate that BITC and PEITC, the two strongest proteasome inhibitors, significantly suppress growth of multiple myeloma (MM) cells through induction of cell cycle arrest at G₂/M phase and apoptosis. This study suggests that proteasome, like tubulin, is a potential molecular target of ITCs, thus providing a novel mechanism by which ITCs strongly inhibit growth of MM cells and new leads in identifying compounds with therapeutic and preventative efficacies for MM. It also supports the future studies of ITCs as therapeutic and preventive agents for MM.
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Affiliation(s)
- Lixin Mi
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University, Washington, DC 20057, USA.
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Dean JB. Hypercapnia causes cellular oxidation and nitrosation in addition to acidosis: implications for CO2 chemoreceptor function and dysfunction. J Appl Physiol (1985) 2010; 108:1786-95. [PMID: 20150563 PMCID: PMC2886689 DOI: 10.1152/japplphysiol.01337.2009] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2009] [Accepted: 02/08/2010] [Indexed: 12/22/2022] Open
Abstract
Cellular mechanisms of CO2 chemoreception are discussed and debated in terms of the stimuli produced during hypercapnic acidosis and their molecular targets: protons generated by the hydration of CO2 and dissociation of carbonic acid, which target membrane-bound proteins and lipids in brain stem neurons. The CO2 hydration reaction, however, is not the only reaction that CO2 undergoes that generates molecules capable of modifying proteins and lipids. Molecular CO2 also reacts with peroxynitrite (ONOO-), a reactive nitrogen species (RNS), which is produced from nitric oxide (*NO) and superoxide (*O2-). The CO2/ONOO- reaction, in turn, produces additional nitrosative and oxidative reactive intermediates. Furthermore, protons facilitate additional redox reactions that generate other reactive oxygen species (ROS). ROS/RNS generated by these redox reactions may act as additional stimuli of CO2 chemoreceptors since neurons in chemosensitive areas produce both *NO and *O2- and, therefore, ONOO-. Perturbing *NO, *O2-, and ONOO- activities in chemosensitive areas modulates cardiorespiration. Moreover, neurons in at least one chemosensitive area, the solitary complex, are stimulated by cellular oxidation. Together, these data raise the following two questions: 1) do pH and ROS/RNS work in tandem to stimulate CO2 chemoreceptors during hypercapnic acidosis; and 2) does nitrosative stress and oxidative stress contribute to CO2 chemoreceptor dysfunction? To begin considering these two issues and their implications for central chemoreception, this minireview has the following three goals: 1) summarize the nitrosative and oxidative reactions that occur during hypercapnic acidosis and isocapnic acidosis; 2) review the evidence that redox signaling occurs in chemosensitive areas; and 3) review the evidence that neurons in the solitary complex are stimulated by cellular oxidation.
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Affiliation(s)
- Jay B Dean
- Department of Molecular Pharmacology and Physiology, Hyperbaric Biomedical Research Laboratory, University of South Florida, College of Medicine, MDC 8, 12901 Bruce B. Downs Blvd., Tampa, Florida 33612, USA.
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Raičević S, Čubrilo D, Arsenijević S, Vukčevic G, Živković V, Vuletić M, Barudžić N, Andjelković N, Antonović O, Jakovljević V. Oxidative stress in fetal distress: potential prospects for diagnosis. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2010. [PMID: 20716946 PMCID: PMC2952080 DOI: 10.4161/oxim.3.3.7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Our aim was to investigate the relation between fetal distress and oxidative stress. Fetal distress was associated with increased concentration of superoxide in the fetal blood and with significant increase of the level of H2O2 in both maternal and fetal blood. The activity of superoxide dismutase was increased roughly sixfold (p<0.01) in the maternal (7330 +/- 2240 U/g of hemoglobin in controls (C) and 36811 +/- 16862 U/g in fetal distress (FD)) and fetal blood (C: 5930 +/- 2641 U/g; FD: 41912 +/- 17133 U/g). In contrast, fetal distress was related to a considerable decrease of catalase activity in both maternal (C: 26011 +/- 8811 U/g; FD: 7212 +/- 1270 U/g) and fetal blood (C: 37194 +/- 9191 U/g; FD: 6173 +/- 1965 U/g). From this we concluded that in fetal distress, the maternal and fetal bloods are exposed to superoxide- and H2O2-mediated oxidative stress, which could be initiated by hypoxic conditions in the fetal blood and placenta. A tremendous increase/decrease of the activities of superoxide dismutase/catalase in the blood of women bearing a distressed fetus in comparison to healthy subjects implies that the assessment of superoxide dismutase/catalase activity could be of use for establishing a timely and accurate ante- or intrapartum diagnosis of fetal distress.
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Affiliation(s)
- Saša Raičević
- Clinic of Gynecology and Obstetrics; Clinical Centre of Montenegro; Podgorica, Montenegro
| | - Dejan Čubrilo
- Department of Physiology; Faculty of Medicine; University of Kragujevac; Kragujevac, Serbia
| | | | - Gordana Vukčevic
- Clinic of Gynecology and Obstetrics; Clinical Centre of Montenegro; Podgorica, Montenegro
| | - Vladimir Živković
- Department of Physiology; Faculty of Medicine; University of Kragujevac; Kragujevac, Serbia
| | - Milena Vuletić
- Department of Physiology; Faculty of Medicine; University of Kragujevac; Kragujevac, Serbia
| | - Nevena Barudžić
- Department of Physiology; Faculty of Medicine; University of Kragujevac; Kragujevac, Serbia
| | - Nebojša Andjelković
- Department of Haematology Internal Clinic; Clinical Centre ”Kragujevac“; Faculty of Medicine; University of Kragujevac; Kragujevac, Serbia
| | - Olga Antonović
- Department of Neonatology; Institute for Gynecology and Obstetrics; Clinical Centre of Serbia; Belgrade, Serbia
| | - Vladimir Jakovljević
- Department of Physiology; Faculty of Medicine; University of Kragujevac; Kragujevac, Serbia
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