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Chao YM, Rauchová H, Chan JYH. Disparate Roles of Oxidative Stress in Rostral Ventrolateral Medulla in Age-Dependent Susceptibility to Hypertension Induced by Systemic l-NAME Treatment in Rats. Biomedicines 2022; 10:biomedicines10092232. [PMID: 36140333 PMCID: PMC9496567 DOI: 10.3390/biomedicines10092232] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2022] [Revised: 09/03/2022] [Accepted: 09/06/2022] [Indexed: 12/12/2022] Open
Abstract
This study aims to investigate whether tissue oxidative stress in the rostral ventrolateral medulla (RVLM), where sympathetic premotor neurons reside, plays an active role in age-dependent susceptibility to hypertension in response to nitric oxide (NO) deficiency induced by systemic l-NAME treatment, and to decipher the underlying molecular mechanisms. Systolic blood pressure (SBP) and heart rate (HR) in conscious rats were recorded, along with measurements of plasma and RVLM level of NO and reactive oxygen species (ROS), and expression of mRNA and protein involved in ROS production and clearance, in both young and adult rats subjected to intraperitoneal (i.p.) infusion of l-NAME. Pharmacological treatments were administered by oral gavage or intracisternal infusion. Gene silencing of target mRNA was made by bilateral microinjection into RVLM of lentivirus that encodes a short hairpin RNA (shRNA) to knock down gene expression of NADPH oxidase activator 1 (Noxa1). We found that i.p. infusion of l-NAME resulted in increases in SBP, sympathetic neurogenic vasomotor activity, and plasma norepinephrine levels in an age-dependent manner. Systemic l-NAME also evoked oxidative stress in RVLM of adult, but not young rats, accompanied by augmented enzyme activity of NADPH oxidase and reduced mitochondrial electron transport enzyme activities. Treatment with L-arginine via oral gavage or infusion into the cistern magna (i.c.), but not i.c. tempol or mitoQ10, significantly offset the l-NAME-induced hypertension in young rats. On the other hand, all treatments appreciably reduced l-NAME-induced hypertension in adult rats. The mRNA microarray analysis revealed that four genes involved in ROS production and clearance were differentially expressed in RVLM in an age-related manner. Of them, Noxa1, and GPx2 were upregulated and Duox2 and Ucp3 were downregulated. Systemic l-NAME treatment caused greater upregulation of Noxa1, but not Ucp3, mRNA expression in RVLM of adult rats. Gene silencing of Noxa1 in RVLM effectively alleviated oxidative stress and protected adult rats against l-NAME-induced hypertension. These data together suggest that hypertension induced by systemic l-NAME treatment in young rats is mediated primarily by NO deficiency that occurs both in vascular smooth muscle cells and RVLM. On the other hand, enhanced augmentation of oxidative stress in RVLM may contribute to the heightened susceptibility of adult rats to hypertension induced by systemic l-NAME treatment.
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Affiliation(s)
- Yung-Mei Chao
- Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung 833, Taiwan
| | - Hana Rauchová
- Institute of Physiology, Czech Academy of Sciences, 14200 Prague, Czech Republic
| | - Julie Y. H. Chan
- Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung 833, Taiwan
- Correspondence: ; Tel.: +886-77338415
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Kodama T, Otani K, Okada M, Yamawaki H. Eukaryotic elongation factor 2 kinase inhibitor, A484954 inhibits perivascular sympathetic nerve stimulation-induced vasoconstriction in isolated renal artery. Eur J Pharmacol 2022; 926:175042. [DOI: 10.1016/j.ejphar.2022.175042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 05/16/2022] [Accepted: 05/16/2022] [Indexed: 11/27/2022]
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Jensen LJ, Lund MA, Salomonsson M, Goetze JP, Jonassen TE, Holstein-Rathlou NH, Axelsen LN, Sørensen CM. Diet-induced hypertension in rats is associated with increased renal vasoconstrictor response to angiotensin II after imitated endothelial dysfunction. Microvasc Res 2022; 141:104333. [DOI: 10.1016/j.mvr.2022.104333] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Revised: 12/21/2021] [Accepted: 01/24/2022] [Indexed: 11/16/2022]
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Rauchová H. Coenzyme Q10 effects in neurological diseases. Physiol Res 2021. [DOI: 10.33549//physiolres.934712] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Coenzyme Q10 (CoQ10), a lipophilic substituted benzoquinone, is present in animal and plant cells. It is endogenously synthetized in every cell and involved in a variety of cellular processes. CoQ10 is an obligatory component of the respiratory chain in inner mitochondrial membrane. In addition, the presence of CoQ10 in all cellular membranes and in blood. It is the only endogenous lipid antioxidant. Moreover, it is an essential factor for uncoupling protein and controls the permeability transition pore in mitochondria. It also participates in extramitochondrial electron transport and controls membrane physicochemical properties. CoQ10 effects on gene expression might affect the overall metabolism. Primary changes in the energetic and antioxidant functions can explain its remedial effects. CoQ10 supplementation is safe and well-tolerated, even at high doses. CoQ10 does not cause any serious adverse effects in humans or experimental animals. New preparations of CoQ10 that are less hydrophobic and structural derivatives, like idebenone and MitoQ, are being developed to increase absorption and tissue distribution. The review aims to summarize clinical and experimental effects of CoQ10 supplementations in some neurological diseases such as migraine, Parkinson´s disease, Huntington´s disease, Alzheimer´s disease, amyotrophic lateral sclerosis, Friedreich´s ataxia or multiple sclerosis. Cardiovascular hypertension was included because of its central mechanisms controlling blood pressure in the brainstem rostral ventrolateral medulla and hypothalamic paraventricular nucleus. In conclusion, it seems reasonable to recommend CoQ10 as adjunct to conventional therapy in some cases. However, sometimes CoQ10 supplementations are more efficient in animal models of diseases than in human patients (e.g. Parkinson´s disease) or rather vague (e.g. Friedreich´s ataxia or amyotrophic lateral sclerosis).
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Affiliation(s)
- H Rauchová
- Institute of Physiology Czech Academy of Sciences, Prague, Czech Republic.
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Chang HH, Lin IC, Wu CW, Hung CY, Liu WC, Wu CY, Cheng CL, Wu KLH. High fructose induced osteogenic differentiation of human valve interstitial cells via activating PI3K/AKT/mitochondria signaling. Biomed J 2021; 45:491-503. [PMID: 34229104 PMCID: PMC9421924 DOI: 10.1016/j.bj.2021.06.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Revised: 06/01/2021] [Accepted: 06/29/2021] [Indexed: 01/01/2023] Open
Abstract
Background Aortic valve stenosis (AS) is a common, lethal cardiovascular disease. There is no cure except the valve replacement at last stage. Therefore, an understanding of the detail mechanism is imperative to prevent and intervene AS. Metabolic syndrome (MetS) is one of the major risk factors of AS whereas fructose overconsuming tops the list of MetS risk factors. However, whether the fructose under physiological level induces AS is currently unknown. Methods The human valve interstitial cells (hVICs), a crucial source to develop calcification, were co-incubated with fructose at 2 or 20 mM to mimic the serum fructose at fasting or post-fructose consumption, respectively, for 24 h. The cell proliferation was evaluated by WST-1 assays. The expressions of osteogenic and fibrotic proteins, PI3K/AKT signaling, insulin receptor substrate 1 and mitochondrial dynamic proteins were detected by Western blot analyses. The mitochondrial oxidative phosphorylation (OXPHOS) was examined by Seahorse analyzer. Results hVICs proliferation was significantly suppressed by 20 mM fructose. The expressions of alkaline phosphatase (ALP) and osteocalcin were enhanced concurrent with the upregulated PI3K p85, AKT, phospho(p)S473-AKT, and pS636-insulin receptor substrate 1 (p-IRS-1) by high fructose. Moreover, ATP production capacity and maximal respiratory capacity were enhanced in the high fructose groups. Synchronically, the expressions of mitochondrial fission 1 and optic atrophy type 1 were increased. Conclusions These results suggested that high fructose stimulated the osteogenic differentiation of hVICs via the activation of PI3K/AKT/mitochondria signaling at the early stage. These results implied that high fructose at physiological level might have a direct, hazard effect on the progression of AS.
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Affiliation(s)
- Hsiao-Huang Chang
- Department of Surgery, School of Medicine, Taipei Medical University, Taipei, Taiwan; Division of Cardiovascular Surgery, Department of Surgery, Taipei Veterans General Hospital, Taipei, Taiwan
| | - I-Chun Lin
- Department of Pediatrics, Chang Gung Memorial Hospital at Kaohsiung, Kaohsiung, Taiwan; College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Chih-Wei Wu
- Institute for Translational Research in Biomedicine, Chang Gung Memorial Hospital at Kaohsiung, Kaohsiung, Taiwan; Department of Accounting and Information System, National Kaohsiung University of Science and Technology, Kaohsiung, Taiwan; Department of Counseling, National Chiayi University, Chiayi, Taiwan
| | - Chun-Ying Hung
- Institute for Translational Research in Biomedicine, Chang Gung Memorial Hospital at Kaohsiung, Kaohsiung, Taiwan
| | - Wen-Chung Liu
- Plastic Surgery, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan
| | - Cai-Yi Wu
- Plastic Surgery, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan
| | - Ching-Li Cheng
- Department of Nursing, National Tainan Institute of Nursing, Tainan, Taiwan.
| | - Kay L H Wu
- Institute for Translational Research in Biomedicine, Chang Gung Memorial Hospital at Kaohsiung, Kaohsiung, Taiwan; Department of Senior Citizen Services, National Tainan Institute of Nursing, Tainan, Taiwan.
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Lee H, Jose PA. Coordinated Contribution of NADPH Oxidase- and Mitochondria-Derived Reactive Oxygen Species in Metabolic Syndrome and Its Implication in Renal Dysfunction. Front Pharmacol 2021; 12:670076. [PMID: 34017260 PMCID: PMC8129499 DOI: 10.3389/fphar.2021.670076] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2021] [Accepted: 04/14/2021] [Indexed: 12/16/2022] Open
Abstract
Metabolic syndrome (MetS), a complex of interrelated risk factors for cardiovascular disease and diabetes, is comprised of central obesity (increased waist circumference), hyperglycemia, dyslipidemia (high triglyceride blood levels, low high-density lipoprotein blood levels), and increased blood pressure. Oxidative stress, caused by the imbalance between pro-oxidant and endogenous antioxidant systems, is the primary pathological basis of MetS. The major sources of reactive oxygen species (ROS) associated with MetS are nicotinamide-adenine dinucleotide phosphate (NADPH) oxidases and mitochondria. In this review, we summarize the current knowledge regarding the generation of ROS from NADPH oxidases and mitochondria, discuss the NADPH oxidase- and mitochondria-derived ROS signaling and pathophysiological effects, and the interplay between these two major sources of ROS, which leads to chronic inflammation, adipocyte proliferation, insulin resistance, and other metabolic abnormalities. The mechanisms linking MetS and chronic kidney disease are not well known. The role of NADPH oxidases and mitochondria in renal injury in the setting of MetS, particularly the influence of the pyruvate dehydrogenase complex in oxidative stress, inflammation, and subsequent renal injury, is highlighted. Understanding the molecular mechanism(s) underlying MetS may lead to novel therapeutic approaches by targeting the pyruvate dehydrogenase complex in MetS and prevent its sequelae of chronic cardiovascular and renal diseases.
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Affiliation(s)
- Hewang Lee
- Department of Medicine, The George Washington University School of Medicine and Health Sciences, Washington, DC, United States
| | - Pedro A Jose
- Department of Medicine, The George Washington University School of Medicine and Health Sciences, Washington, DC, United States.,Department of Pharmacology and Physiology, The George Washington University School of Medicine and Health Sciences, Washington, DC, United States
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DOVINOVA I, KVANDOVA M, BALIS P, GRESOVA L, MAJZUNOVA M, HORAKOVA L, CHAN J, BARANCIK M. The Role of Nrf2 and PPARγ in the Improvement of Oxidative Stress in Hypertension and Cardiovascular Diseases. Physiol Res 2020. [DOI: 10.33549/physiolres.934612] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Reactive oxygen species are an important element of redox regulation in cells and tissues. During physiological processes, molecules undergo chemical changes caused by reduction and oxidation reactions. Free radicals are involved in interactions with other molecules, leading to oxidative stress. Oxidative stress works two ways depending on the levels of oxidizing agents and products. Excessive action of oxidizing agents damages biomolecules, while a moderate physiological level of oxidative stress (oxidative eustress) is necessary to control life processes through redox signaling required for normal cellular operation. High levels of reactive oxygen species (ROS) mediate pathological changes. Oxidative stress helps to regulate cellular phenotypes in physiological and pathological conditions. Nrf2 (nuclear factor erythroid 2-related factor 2, NFE2L2) transcription factor functions as a target nuclear receptor against oxidative stress and is a key factor in redox regulation in hypertension and cardiovascular disease. Nrf2 mediates transcriptional regulation of a variety of target genes. The Keap1-Nrf2-ARE system regulates many detoxification and antioxidant enzymes in cells after the exposure to reactive oxygen species and electrophiles. Activation of Nrf2/ARE signaling is differentially regulated during acute and chronic stress. Keap1 normally maintains Nrf2 in the cytosol and stimulates its degradation through ubiquitination. During acute oxidative stress, oxidized molecules modify the interaction of Nrf2 and Keap1, when Nrf2 is released from the cytoplasm into the nucleus where it binds to the antioxidant response element (ARE). This triggers the expression of antioxidant and detoxification genes. The consequence of long-term chronic oxidative stress is activation of glycogen synthase kinase 3β (GSK-3β) inhibiting Nrf2 activity and function. PPARγ (peroxisome proliferator-activated receptor gamma) is a nuclear receptor playing an important role in the management of cardiovascular diseases, hypertension and metabolic syndrome. PPARγ targeting of genes with peroxisome proliferator response element (PPRE) has led to the identification of several genes involved in lipid metabolism or oxidative stress. PPARγ stimulation is triggered by endogenous and exogenous ligands – agonists and it is involved in the activation of several cellular signaling pathways involved in oxidative stress response, such as the PI3K/Akt/NOS pathway. Nrf2 and PPARγ are linked together with their several activators and Nrf2/ARE and PPARγ/PPRE pathways can control several types of diseases.
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Affiliation(s)
- I DOVINOVA
- Centre of Experimental Medicine, Slovak Academy Of Sciences, Bratislava, Slovak Republic
| | - M KVANDOVA
- Center for Cardiology, Cardiology I, Medical Center of the Johannes Gutenberg-Universität Mainz, Germany
| | - P BALIS
- Centre of Experimental Medicine, Slovak Academy Of Sciences, Bratislava, Slovak Republic
| | - L GRESOVA
- Centre of Experimental Medicine, Slovak Academy Of Sciences, Bratislava, Slovak Republic
| | - M MAJZUNOVA
- Centre of Experimental Medicine, Slovak Academy Of Sciences, Bratislava, Slovak Republic
| | - L HORAKOVA
- Centre of Experimental Medicine, Slovak Academy Of Sciences, Bratislava, Slovak Republic
| | - J CHAN
- Institute for Translational Research in Biomedicine, Chang Gung Memorial Hospital, Kaohsiung, Taiwan
| | - M BARANCIK
- Centre of Experimental Medicine, Slovak Academy Of Sciences, Bratislava, Slovak Republic
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de Sousa GG, Barbosa MA, Barbosa CM, Lima TC, Souza Dos Santos RA, Campagnole-Santos MJ, Alzamora AC. Different reactive species modulate the hypotensive effect triggered by angiotensins at CVLM of 2K1C hypertensive rats. Peptides 2020; 134:170409. [PMID: 32950566 DOI: 10.1016/j.peptides.2020.170409] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Revised: 08/20/2020] [Accepted: 09/15/2020] [Indexed: 11/18/2022]
Abstract
Hypertension is associated with increased central activity of the renin-angiotensin system (RAS) and oxidative stress. Here, we evaluated whether reactive species and neurotransmitters could contribute to the hypotensive effect induced by angiotensin (Ang) II and Ang-(1-7) at the caudal ventrolateral medulla (CVLM) in renovascular hypertensive rats (2K1C). Therefore, we investigated the effect of Ang II, Ang-(1-7), and the Ang-(1-7) antagonist A-779 microinjected before and after CVLM microinjection of the nitric oxide (NO)-synthase inhibitor, (L-NAME), vitamin C (Vit C), bicuculline, or kynurenic acid in 2K1C and SHAM rats. Baseline values of the mean arterial pressure (MAP) in 2K1C rats were higher than in SHAM rats. CVLM microinjection of Ang II, Ang-(1-7), l-NAME, or bicuculline induced decreases in the MAP in SHAM and 2K1C rats. In addition, Vit C and A-779 produced decreases in the MAP only in 2K1C rats. Kynurenic acid increased the MAP in both SHAM and 2K1C rats. Only the Ang-(1-7) effect was increased by l-NAME and reduced by bicuculline in SHAM rats. L-NAME also reduced the A-779 effect in 2K1C rats. Only the Ang II effect was abolished by CVLM Vit C and enhanced by CVLM kynurenic acid in SHAM and 2K1C rats. Overall, the superoxide anion and glutamate participated in the hypotensive effect of Ang II, while NO and GABA participated in the hypotensive effect of Ang-(1-7) in CVLM. The higher hypotensive response of A-779 in the CVLM of 2K1C rats suggests that Ang-(1-7) contributes to renovascular hypertension.
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Affiliation(s)
- Graziele Galdino de Sousa
- Núcleo de Pesquisa em Ciências Biológicas, Universidade Federal de Ouro Preto, Ouro Preto, MG, Brazil
| | - Maria Andréa Barbosa
- Núcleo de Pesquisa em Ciências Biológicas, Universidade Federal de Ouro Preto, Ouro Preto, MG, Brazil
| | - Claudiane Maria Barbosa
- Núcleo de Pesquisa em Ciências Biológicas, Universidade Federal de Ouro Preto, Ouro Preto, MG, Brazil
| | - Taynara Carolina Lima
- Núcleo de Pesquisa em Ciências Biológicas, Universidade Federal de Ouro Preto, Ouro Preto, MG, Brazil
| | - Robson Augusto Souza Dos Santos
- Departamento de Fisiologia e Biofísica, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | - Maria José Campagnole-Santos
- Departamento de Fisiologia e Biofísica, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | - Andréia Carvalho Alzamora
- Departamento de Ciências Biológicas, Instituto de Ciências Exatas e Biológicas, Brazil; Núcleo de Pesquisa em Ciências Biológicas, Universidade Federal de Ouro Preto, Ouro Preto, MG, Brazil.
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Ally A, Powell I, Ally MM, Chaitoff K, Nauli SM. Role of neuronal nitric oxide synthase on cardiovascular functions in physiological and pathophysiological states. Nitric Oxide 2020; 102:52-73. [PMID: 32590118 DOI: 10.1016/j.niox.2020.06.004] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Revised: 03/15/2020] [Accepted: 06/15/2020] [Indexed: 12/16/2022]
Abstract
This review describes and summarizes the role of neuronal nitric oxide synthase (nNOS) on the central nervous system, particularly on brain regions such as the ventrolateral medulla (VLM) and the periaqueductal gray matter (PAG), and on blood vessels and the heart that are involved in the regulation and control of the cardiovascular system (CVS). Furthermore, we shall also review the functional aspects of nNOS during several physiological, pathophysiological, and clinical conditions such as exercise, pain, cerebral vascular accidents or stroke and hypertension. For example, during stroke, a cascade of molecular, neurochemical, and cellular changes occur that affect the nervous system as elicited by generation of free radicals and nitric oxide (NO) from vulnerable neurons, peroxide formation, superoxides, apoptosis, and the differential activation of three isoforms of nitric oxide synthases (NOSs), and can exert profound effects on the CVS. Neuronal NOS is one of the three isoforms of NOSs, the others being endothelial (eNOS) and inducible (iNOS) enzymes. Neuronal NOS is a critical homeostatic component of the CVS and plays an important role in regulation of different systems and disease process including nociception. The functional and physiological roles of NO and nNOS are described at the beginning of this review. We also elaborate the structure, gene, domain, and regulation of the nNOS protein. Both inhibitory and excitatory role of nNOS on the sympathetic autonomic nervous system (SANS) and parasympathetic autonomic nervous system (PANS) as mediated via different neurotransmitters/signal transduction processes will be explored, particularly its effects on the CVS. Because the VLM plays a crucial function in cardiovascular homeostatic mechanisms, the neuroanatomy and cardiovascular regulation of the VLM will be discussed in conjunction with the actions of nNOS. Thereafter, we shall discuss the up-to-date developments that are related to the interaction between nNOS and cardiovascular diseases such as hypertension and stroke. Finally, we shall focus on the role of nNOS, particularly within the PAG in cardiovascular regulation and neurotransmission during different types of pain stimulus. Overall, this review focuses on our current understanding of the nNOS protein, and provides further insights on how nNOS modulates, regulates, and controls cardiovascular function during both physiological activity such as exercise, and pathophysiological conditions such as stroke and hypertension.
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Affiliation(s)
- Ahmmed Ally
- Arkansas College of Osteopathic Medicine, Fort Smith, AR, USA.
| | - Isabella Powell
- All American Institute of Medical Sciences, Black River, Jamaica
| | | | - Kevin Chaitoff
- Interventional Rehabilitation of South Florida, West Palm Beach, FL, USA
| | - Surya M Nauli
- Chapman University and University of California, Irvine, CA, USA.
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Chao YM, Wu KLH, Tsai PC, Tain YL, Leu S, Lee WC, Chan JYH. Anomalous AMPK-regulated angiotensin AT 1R expression and SIRT1-mediated mitochondrial biogenesis at RVLM in hypertension programming of offspring to maternal high fructose exposure. J Biomed Sci 2020; 27:68. [PMID: 32446297 PMCID: PMC7245869 DOI: 10.1186/s12929-020-00660-z] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Accepted: 05/14/2020] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Tissue oxidative stress, sympathetic activation and nutrient sensing signals are closely related to adult hypertension of fetal origin, although their interactions in hypertension programming remain unclear. Based on a maternal high-fructose diet (HFD) model of programmed hypertension, we tested the hypothesis that dysfunction of AMP-activated protein kinase (AMPK)-regulated angiotensin type 1 receptor (AT1R) expression and sirtuin1 (SIRT1)-dependent mitochondrial biogenesis contribute to tissue oxidative stress and sympathoexcitation in programmed hypertension of young offspring. METHODS Pregnant female rats were randomly assigned to receive normal diet (ND) or HFD (60% fructose) chow during pregnancy and lactation. Both ND and HFD offspring returned to ND chow after weaning, and blood pressure (BP) was monitored from age 6 to 12 weeks. At age of 8 weeks, ND and HFD offspring received oral administration of simvastatin or metformin; or brain microinfusion of losartan. BP was monitored under conscious condition by the tail-cuff method. Nutrient sensing molecules, AT1R, subunits of NADPH oxidase, mitochondrial biogenesis markers in rostral ventrolateral medulla (RVLM) were measured by Western blot analyses. RVLM oxidative stress was measured by fluorescent probe dihydroethidium and lipid peroxidation by malondialdehyde assay. Mitochondrial DNA copy number was determined by quantitative real-time polymerase chain reaction. RESULTS Increased systolic BP, plasma norepinephrine level and sympathetic vasomotor activity were exhibited by young HFD offspring. Reactive oxygen species (ROS) level was also elevated in RVLM where sympathetic premotor neurons reside, alongside augmented protein expressions of AT1R and pg91phox subunit of NADPH oxidase, decrease in superoxide dismutase 2; and suppression of transcription factors for mitochondrial biogenesis, peroxisome proliferator-activated receptor γ co-activator α (PGC-1α) and mitochondrial transcription factor A (TFAM). Maternal HFD also attenuated AMPK phosphorylation and protein expression of SIRT1 in RVLM of young offspring. Oral administration of a HMG-CoA reductase inhibitor, simvastatin, or an AMPK activator, metformin, to young HFD offspring reversed maternal HFD-programmed increase in AT1R and decreases in SIRT1, PGC-1α and TFAM; alleviated ROS production in RVLM, and attenuated sympathoexcitation and hypertension. CONCLUSION Dysfunction of AMPK-regulated AT1R expression and SIRT1-mediated mitochondrial biogenesis may contribute to tissue oxidative stress in RVLM, which in turn primes increases of sympathetic vasomotor activity and BP in young offspring programmed by excessive maternal fructose consumption.
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Affiliation(s)
- Yung-Mei Chao
- Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, 83301, Taiwan
| | - Kay L H Wu
- Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, 83301, Taiwan
| | - Pei-Chia Tsai
- Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, 83301, Taiwan
| | - You-Lin Tain
- Department of Pediatrics, Kaohsiung Chang Gung Memorial Hospital and Chang Gung Univeristy College of Medicine, Kaohsiung, 83301, Taiwan
| | - Steve Leu
- Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, 83301, Taiwan
| | - Wei-Chia Lee
- Division of Urology, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, 83301, Taiwan
| | - Julie Y H Chan
- Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, 83301, Taiwan.
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Sharma NM, Haibara AS, Katsurada K, Liu X, Patel KP. Central angiotensin II-Protein inhibitor of neuronal nitric oxide synthase (PIN) axis contribute to neurogenic hypertension. Nitric Oxide 2019; 94:54-62. [PMID: 31654775 DOI: 10.1016/j.niox.2019.10.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Revised: 09/17/2019] [Accepted: 10/17/2019] [Indexed: 02/07/2023]
Abstract
Activation of renin-angiotensin- system, nitric oxide (NO•) bioavailability and subsequent sympathoexcitation plays a pivotal role in the pathogenesis of many cardiovascular diseases, including hypertension. Previously we have shown increased protein expression of PIN (a protein inhibitor of nNOS: neuronal nitric oxide synthase, known to dissociate nNOS dimers into monomers) with concomitantly reduced levels of catalytically active dimers of nNOS in the PVN of rats with heart failure. To elucidate the molecular mechanism by which Angiotensin II (Ang II) increases PIN expression, we used Sprague-Dawley rats (250-300 g) subjected to intracerebroventricular infusion of Ang II (20 ng/min, 0.5 μl/h) or saline as vehicle (Veh) for 14 days through osmotic mini-pumps and NG108-15 hybrid neuronal cell line treated with Ang II as an in vitro model. Ang II infusion significantly increased baseline renal sympathetic nerve activity and mean arterial pressure. Ang II infusion increased the expression of PIN (1.24 ± 0.04* Ang II vs. 0.65 ± 0.07 Veh) with a concomitant 50% decrease in dimeric nNOS and PIN-Ub conjugates (0.73 ± 0.04* Ang II vs. 1.00 ± 0.03 Veh) in the PVN. Substrate-dependent ligase assay in cells transfected with pCMV-(HA-Ub)8 vector revealed a reduction of HA-Ub-PIN conjugates after Ang II and a proteasome inhibitor, Lactacystin (LC), treatment (4.5 ± 0.7* LC Ang II vs. 9.2 ± 2.5 LC). TUBE (Tandem Ubiquitin-Binding Entities) assay showed decrease PIN-Ub conjugates in Ang II-treated cells (0.82 ± 0.12* LC Ang II vs. 1.21 ± 0.06 LC) while AT1R blocker, Losartan (Los) treatment diminished the Ang II-mediated stabilization of PIN (1.21 ± 0.07 LC Los vs. 1.16 ± 0.04* LC Ang II Los). Taken together, our studies suggest that increased central levels of Ang II contribute to the enhanced expression of PIN leading to reduced expression of the dimeric form of nNOS, thus diminishing the inhibitory action of NO• on pre-autonomic neurons in the PVN resulting in increased sympathetic outflow.
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Affiliation(s)
- Neeru M Sharma
- Department of Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha, NE, 68198-5850, USA.
| | - Andrea S Haibara
- Department of Physiology and Biophysics, University of Minas Gerais, Belo Horizonte, MG, 31270-910, Brazil
| | - Kenichi Katsurada
- Department of Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha, NE, 68198-5850, USA
| | - Xuefei Liu
- Department of Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha, NE, 68198-5850, USA
| | - Kaushik P Patel
- Department of Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha, NE, 68198-5850, USA
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High fructose diet induces early mortality via autophagy factors accumulation in the rostral ventrolateral medulla as ameliorated by pioglitazone. J Nutr Biochem 2019; 69:87-97. [PMID: 31063919 DOI: 10.1016/j.jnutbio.2019.03.014] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2018] [Revised: 02/11/2019] [Accepted: 03/14/2019] [Indexed: 02/07/2023]
Abstract
High fructose ingestion enhances mortality which has been linked to autonomic dysregulation. However, the underlying mechanisms are still largely unknown. In the present study, we demonstrated that 3 months of high fructose diet (HFD) ingestion induced mortality in 18-week-old Wistar Kyoto rats (WKY) during anesthesia. Concurrently, the low frequency (LF) and the high frequency (HF) elements of the power spectral analyses of SBP were increased. Of note, the decreased ratio of LF and HF (LF/HF), an index of sympathetic and parasympathetic balance, suggested an autonomic imbalance. In the rostral ventrolateral medulla (RVLM), a center of sympathetic outflow, the levels of presynaptic (synaptophysin) and postsynaptic (postsynaptic density protein 95 and phospho-Ca2+/calmodulin-dependent protein kinase II) proteins were increased. The down-regulation of insulin receptor β and insulin receptor substrate 1 suggested the status of insulin desensitization. Moreover, the up-regulation of AMP-activated protein kinase and sirtuin 1 suggested the enhancement of energy sensing to activate autophagy. Simultaneously, the accumulations of Beclin-1, ATG12 and LC3B were increased in RVLM. Pioglitazone (PIO), an insulin sensitizer, effectively relieved the accumulation of Beclin-1 and ATG12 as well as the synaptic proteins synchronized with the reverses of insulin and energy sensing signals. Moreover, the autonomic dysregulation and anesthesia-associated mortality were intervened. Together, these results suggested that the HFD-induced, anesthesia-associated mortality rate was related to the autonomic abnormality derived from the RVLM synaptic alteration, which is strongly related to insulin desensitization-associated autophagy. PIO intervened the HFD-induced mortality via reversal of the above-mentioned molecules.
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13
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Chan JYH, Chan SHH. Differential impacts of brain stem oxidative stress and nitrosative stress on sympathetic vasomotor tone. Pharmacol Ther 2019; 201:120-136. [PMID: 31153955 DOI: 10.1016/j.pharmthera.2019.05.015] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Accepted: 05/24/2019] [Indexed: 02/07/2023]
Abstract
Based on work-done in the rostral ventrolateral medulla (RVLM), this review presents four lessons learnt from studying the differential impacts of oxidative stress and nitrosative stress on sympathetic vasomotor tone and their clinical and therapeutic implications. The first lesson is that an increase in sympathetic vasomotor tone because of augmented oxidative stress in the RVLM is responsible for the generation of neurogenic hypertension. On the other hand, a shift from oxidative stress to nitrosative stress in the RVLM underpins the succession of increase to decrease in sympathetic vasomotor tone during the progression towards brain stem death. The second lesson is that, by having different cellular sources, regulatory mechanisms on synthesis and degradation, kinetics of chemical reactions, and downstream signaling pathways, reactive oxygen species and reactive nitrogen species should not be regarded as a singular moiety. The third lesson is that well-defined differential roles of oxidative stress and nitrosative stress with distinct regulatory mechanisms in the RVLM during neurogenic hypertension and brain stem death clearly denote that they are not interchangeable phenomena with unified cellular actions. Special attention must be paid to their beneficial or detrimental roles under a specific disease or a particular time-window of that disease. The fourth lesson is that, to be successful, future antioxidant therapies against neurogenic hypertension must take into consideration the much more complicated picture than that presented in this review on the generation, maintenance, regulation or modulation of the sympathetic vasomotor tone. The identification that the progression towards brain stem death entails a shift from oxidative stress to nitrosative stress in the RVLM may open a new vista for therapeutic intervention to slow down this transition.
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Affiliation(s)
- Julie Y H Chan
- Institute for Translational Research in Biomedicine, Chang Gung Memorial Hospital, Kaohsiung, Taiwan, Republic of China
| | - Samuel H H Chan
- Institute for Translational Research in Biomedicine, Chang Gung Memorial Hospital, Kaohsiung, Taiwan, Republic of China.
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14
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Dovinova I, Barančík M, Miroslava K, Miroslava M, Eva H, Eugene J, Andreas M, Čačányiová S. ABERRANT REDOX REGULATION AND DEVELOPMENT OF RISK MARKERS IN CARDIOVASCULAR DISEASES. PATHOPHYSIOLOGY 2018. [DOI: 10.1016/j.pathophys.2018.07.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
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15
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Chan SHH, Chan JYH. Mitochondria and Reactive Oxygen Species Contribute to Neurogenic Hypertension. Physiology (Bethesda) 2018; 32:308-321. [PMID: 28615314 DOI: 10.1152/physiol.00006.2017] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2017] [Revised: 04/05/2017] [Accepted: 04/13/2017] [Indexed: 02/07/2023] Open
Abstract
Beyond its primary role as fuel generators, mitochondria are engaged in a variety of cellular processes, including redox homeostasis. Mitochondrial dysfunction, therefore, may have a profound impact on high-energy-demanding organs such as the brain. Here, we review the roles of mitochondrial biogenesis and bioenergetics, and their associated signaling in cellular redox homeostasis, and illustrate their contributions to the oxidative stress-related neural mechanism of hypertension, focusing on specific brain areas that are involved in the generation or modulation of sympathetic outflows to the cardiovascular system. We also highlight future challenges of research on mitochondrial physiology and pathophysiology.
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Affiliation(s)
- Samuel H H Chan
- Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan
| | - Julie Y H Chan
- Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan
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16
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Yeh TC, Shin CS, Chen HH, Lai CC, Sun GC, Tseng CJ, Cheng PW. Resveratrol regulates blood pressure by enhancing AMPK signaling to downregulate a Rac1-derived NADPH oxidase in the central nervous system. J Appl Physiol (1985) 2018; 125:40-48. [DOI: 10.1152/japplphysiol.00686.2017] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Resveratrol is a polyphenol with pleiotropic effects against oxidative damage that has been widely implicated in lowering hypertension risk. The purpose of this study was to determine whether improve nitric oxide (NO) release in the brain, either through the activation of AMP-activated protein kinase (AMPK) or reduced Ras-related C3 botulinum toxin substrate 1 (Rac1)-induced reactive oxygen species (ROS) generation, thereby reducing blood pressure (BP) in rats with fructose-induced hypertension. The rats were fed with 10% fructose or Crestor (rosuvastatin; 1.5 mg·kg−1·day−1) and resveratrol (10 mg·kg−1·day−1) treatment for 1 wk, then the systolic blood pressure of the rats was measured by tail-cuff method. Endogenous in vivo superoxide radical production in the nucleus tractus solitarii (NTS) was determined with dihydroethidium. Immunoblotting analyses were used to quantify protein expression levels. Oral resveratrol treatment for 1 wk decreased BP and increased NO production in the NTS of fructose-fed rats but not in the control Wistar-Kyoto rats. The effect of Crestor is opposite that of resveratrol. Fructose induced hypertension by inactivating AMPK, which in turn enhanced the generation of ROS and reduced manganese superoxide dismutase by increasing the activity of Rac1-induced NADPH oxidase, abolishing the activity of the extracellular signal-regulated kinases 1 and 2 (ERK1/2) and ribosomal protein S6 kinase (RSK) and neuronal nitric oxide synthase (nNOS) phosphorylation signaling pathway in the brain. However, resveratrol had the opposite effect in the fructose-fed rats. Overall, we show that the resveratrol decreased BP better than Crestor, abolished ROS generation, and enhanced the ERK1/2-RSK-nNOS pathway by activating AMPK to downregulate Rac1-induced NADPH oxidase levels in the NTS during oxidative stress–associated hypertension. NEW & NOTEWORTHY 1) Evidence showed that the Ras-related C3 botulinum toxin substrate 1 (Rac1) augmented by Crestor (rosuvastatin) did not result in a significant change in blood pressure (BP) in fructose-induced hypertension. 2) Fructose induced hypertension by inactivating AMP-activated protein kinase (AMPK), which in turn enhanced the generation of reactive oxygen species (ROS) and reduced manganese superoxide dismutase in the brain. 3) Resveratrol decreased BP better than Crestor, abolished ROS generation, and enhanced the ERK1/2-ribosomal protein S6 kinase-neuronal nitric oxide synthase pathway by activating AMPK to negatively regulate Rac1-induced NADPH oxidase levels in the nucleus tractus solitarii during oxidative stress–associated hypertension.
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Affiliation(s)
- Tung-Chen Yeh
- Department of Internal Medicine, Division of Cardiology, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan
- Chung Hwa University of Medical Technology, Tainan, Taiwan
| | - Ching-Sen Shin
- The Section of Neurology, Department of Internal Medicine, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan
| | - Hsin-Hung Chen
- Department of Medical Education and Research, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan
| | - Chi-Cheng Lai
- Department of Internal Medicine, Division of Cardiology, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan
| | - Gwo-Ching Sun
- Department of Anesthesiology, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Ching-Jiunn Tseng
- Department of Medical Education and Research, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan
- Department of Medical Research, China Medical University Hospital, China Medical University, Taichung 40402, Taiwan
- Department of Pharmacology, National Defense Medical Center, Taipei, Taiwan
| | - Pei-Wen Cheng
- Department of Medical Education and Research, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan
- Yuh-Ing Junior College of Health Care & Management, Kaohsiung, Taiwan
- Shu-Zen Junior College of Medicine and Management, Kaohsiung, Taiwan
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17
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Nash KM, Schiefer IT, Shah ZA. Development of a reactive oxygen species-sensitive nitric oxide synthase inhibitor for the treatment of ischemic stroke. Free Radic Biol Med 2018; 115:395-404. [PMID: 29275014 DOI: 10.1016/j.freeradbiomed.2017.12.027] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/20/2017] [Revised: 11/28/2017] [Accepted: 12/20/2017] [Indexed: 01/25/2023]
Abstract
Ischemic stroke is caused by a blockage of cerebral blood flow resulting in neuronal and glial hypoxia leading to inflammatory and reactive oxygen species (ROS)-mediated cell death. Nitric oxide (NO) formed by NO synthase (NOS) is known to be protective in ischemic stroke, however NOS has been shown to 'uncouple' under oxidative conditions to instead produce ROS. Nitrones are antioxidant molecules that are shown to trap ROS to then decompose and release NO. In this study, the nitrone 5 was designed such that its decomposition product is a NOS inhibitor, 6, effectively leading to NOS inhibition specifically at the site of ROS production. The ability of 5 to spin-trap radicals and decompose to 6 was observed using EPR and LC-MS/MS. The pro-drug concept was tested in vitro by measuring cell viability and 6 formation in SH-SY5Y cells subjected to oxygen glucose deprivation (OGD). 5 was found to be more efficacious and more potent than PBN, and was able to increase phospho-Akt while reducing nitrotyrosine and cleaved caspase-3 levels. 6 treatment, but not 5, was found to decrease NO production in LPS-stimulated microglia. Doppler flowmetry on anesthetized mice showed increased cerebral blood flow upon intravenous administration of 1mg/kg of 5, but a return to baseline upon administration of 10mg/kg, likely due to its dual nature of antioxidant/NO-donor and NOS-inhibition. Mice treated with 5 after permanent ischemia exhibited a >30% reduction in infarct volume, and higher formation of 6 in ischemic tissue resulting in region specific effects limited to the infarct area.
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Affiliation(s)
- Kevin M Nash
- Department of Pharmacology and Experimental Therapeutics, College of Pharmacy and Pharmaceutical Sciences, University of Toledo, USA
| | - Isaac T Schiefer
- Department of Medicinal and Biological Chemistry, College of Pharmacy and Pharmaceutical Sciences, University of Toledo, OH 43614, USA.
| | - Zahoor A Shah
- Department of Medicinal and Biological Chemistry, College of Pharmacy and Pharmaceutical Sciences, University of Toledo, OH 43614, USA.
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18
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Mui RK, Fernandes RN, Garver HG, Van Rooijen N, Galligan JJ. Macrophage-dependent impairment of α 2-adrenergic autoreceptor inhibition of Ca 2+ channels in sympathetic neurons from DOCA-salt but not high-fat diet-induced hypertensive rats. Am J Physiol Heart Circ Physiol 2018; 314:H863-H877. [PMID: 29351460 DOI: 10.1152/ajpheart.00536.2017] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
DOCA-salt and obesity-related hypertension are associated with inflammation and sympathetic nervous system hyperactivity. Prejunctional α2-adrenergic receptors (α2ARs) provide negative feedback to norepinephrine release from sympathetic nerves through inhibition of N-type Ca2+ channels. Increased neuronal norepinephrine release in DOCA-salt and obesity-related hypertension occurs through impaired α2AR signaling; however, the mechanisms involved are unclear. Mesenteric arteries are resistance arteries that receive sympathetic innervation from the superior mesenteric and celiac ganglia (SMCG). We tested the hypothesis that macrophages impair α2AR-mediated inhibition of Ca2+ channels in SMCG neurons from DOCA-salt and high-fat diet (HFD)-induced hypertensive rats. Whole cell patch-clamp methods were used to record Ca2+ currents from SMCG neurons maintained in primary culture. We found that DOCA-salt, but not HFD-induced, hypertension caused macrophage accumulation in mesenteric arteries, increased SMCG mRNA levels of monocyte chemoattractant protein-1 and tumor necrosis factor-α, and impaired α2AR-mediated inhibition of Ca2+ currents in SMCG neurons. α2AR dysfunction did not involve changes in α2AR expression, desensitization, or downstream signaling factors. Oxidative stress impaired α2AR-mediated inhibition of Ca2+ currents in SMCG neurons and resulted in receptor internalization in human embryonic kidney-293T cells. Systemic clodronate-induced macrophage depletion preserved α2AR function and lowered blood pressure in DOCA-salt rats. HFD caused hypertension without obesity in Sprague-Dawley rats and hypertension with obesity in Dahl salt-sensitive rats. HFD-induced hypertension was not associated with inflammation in SMCG and mesenteric arteries or α2AR dysfunction in SMCG neurons. These results suggest that macrophage-mediated α2AR dysfunction in the mesenteric circulation may only be relevant to mineralocorticoid-salt excess. NEW & NOTEWORTHY Here, we identify a contribution of macrophages to hypertension development through impaired α2-adrenergic receptor (α2AR)-mediated inhibition of sympathetic nerve terminal Ca2+ channels in DOCA-salt hypertensive rats. Impaired α2AR function may involve oxidative stress-induced receptor internalization. α2AR dysfunction may be unique to mineralocorticoid-salt excess, as it does not occur in obesity-related hypertension.
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Affiliation(s)
- Ryan K Mui
- Department of Physiology, Michigan State University , East Lansing, Michigan
| | - Roxanne N Fernandes
- Department of Pharmacology and Toxicology, Michigan State University , East Lansing, Michigan
| | - Hannah G Garver
- Department of Pharmacology and Toxicology, Michigan State University , East Lansing, Michigan
| | - Nico Van Rooijen
- Department of Molecular Cell Biology, Vrije Universiteit Medical Center , Amsterdam , The Netherlands
| | - James J Galligan
- Department of Pharmacology and Toxicology, Michigan State University , East Lansing, Michigan.,Neuroscience Program, Michigan State University , East Lansing, Michigan
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19
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Wang XR, Yang JW, Ji CS, Zeng XH, Shi GX, Fisher M, Liu CZ. Inhibition of NADPH Oxidase-Dependent Oxidative Stress in the Rostral Ventrolateral Medulla Mediates the Antihypertensive Effects of Acupuncture in Spontaneously Hypertensive Rats. Hypertension 2017; 71:356-365. [PMID: 29229746 DOI: 10.1161/hypertensionaha.117.09759] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Revised: 06/01/2017] [Accepted: 10/19/2017] [Indexed: 01/06/2023]
Abstract
Oxidative stress in the rostral ventrolateral medulla (RVLM), where the sympathetic nervous control center is located, contributes to neural mechanisms of hypertension. Acupuncture was previously reported to favorably affect high blood pressure. However, little is known about the effect of acupuncture on oxidative stress-modulated mechanisms in hypertension. This study was designed to evaluate the hypothesis that acupuncture exerts an antihypertensive effect via ameliorating oxidative stress and the redox-sensitive pathway in the RVLM of spontaneously hypertensive rats. Two weeks of acupuncture reduced blood pressure and sympathetic nervous system activity in spontaneously hypertensive rats. Oxidative stress in the RVLM was alleviated by acupuncture, accompanied by a decrease in nicotinamide adenine dinucleotide phosphate oxidase activity and expression of its subunits. Acupuncture significantly altered the mitogen-activated protein kinases signaling pathway as assessed by pathway enrichment analysis in a gene chip assay. The phosphorylation of p38 mitogen-activated protein kinases and extracellular signal-regulated protein kinase 1/2, but not Jun N-terminal kinase, was downregulated by acupuncture. Microinjection bilaterally of the superoxide dismutase mimetic tempol, nicotinamide adenine dinucleotide phosphate oxidase inhibitor apocynin, or diphenyleneiodonium chloride into the RVLM mimicked the antihypertensive effect of acupuncture. In contrast, the nicotinamide adenine dinucleotide phosphate oxidase agonist tetrabromocinnamic acid abolished the beneficial effects of acupuncture. Furthermore, injection of capsaicin or surgical sectioning of the sciatic nerve abolished the antihypertensive effect of acupuncture. We conclude that acupuncture decreases high blood pressure and nicotinamide adenine dinucleotide phosphate oxidase in the RVLM of spontaneously hypertensive rats. The mitogen-activated protein kinases and the sciatic nerve are involved in the mechanism of acupuncture's amelioration of hypertension.
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Affiliation(s)
- Xue-Rui Wang
- From the Department of Acupuncture and Moxibustion (X.-R.W., J.-W.Y., C.-S.J., X.-H.Z., G.-X.S., C.-Z.L.) and Beijing Institute of Tradition Chinese Medicine (X.-R.W.), Beijing Hospital of Traditional Chinese Medicine affiliated to Capital Medical University; Beijing Key Laboratory of Acupuncture Neuromodulation, China (X.-R.W., J.-W.Y., C.-S.J., X.-H.Z., G.-X.S., C.-Z.L.); and the Department of Neurology, Beth Israel Deaconess Medical Center, and Harvard Medical School, Boston, MA (M.F.)
| | - Jing-Wen Yang
- From the Department of Acupuncture and Moxibustion (X.-R.W., J.-W.Y., C.-S.J., X.-H.Z., G.-X.S., C.-Z.L.) and Beijing Institute of Tradition Chinese Medicine (X.-R.W.), Beijing Hospital of Traditional Chinese Medicine affiliated to Capital Medical University; Beijing Key Laboratory of Acupuncture Neuromodulation, China (X.-R.W., J.-W.Y., C.-S.J., X.-H.Z., G.-X.S., C.-Z.L.); and the Department of Neurology, Beth Israel Deaconess Medical Center, and Harvard Medical School, Boston, MA (M.F.)
| | - Cai-Shuo Ji
- From the Department of Acupuncture and Moxibustion (X.-R.W., J.-W.Y., C.-S.J., X.-H.Z., G.-X.S., C.-Z.L.) and Beijing Institute of Tradition Chinese Medicine (X.-R.W.), Beijing Hospital of Traditional Chinese Medicine affiliated to Capital Medical University; Beijing Key Laboratory of Acupuncture Neuromodulation, China (X.-R.W., J.-W.Y., C.-S.J., X.-H.Z., G.-X.S., C.-Z.L.); and the Department of Neurology, Beth Israel Deaconess Medical Center, and Harvard Medical School, Boston, MA (M.F.)
| | - Xiang-Hong Zeng
- From the Department of Acupuncture and Moxibustion (X.-R.W., J.-W.Y., C.-S.J., X.-H.Z., G.-X.S., C.-Z.L.) and Beijing Institute of Tradition Chinese Medicine (X.-R.W.), Beijing Hospital of Traditional Chinese Medicine affiliated to Capital Medical University; Beijing Key Laboratory of Acupuncture Neuromodulation, China (X.-R.W., J.-W.Y., C.-S.J., X.-H.Z., G.-X.S., C.-Z.L.); and the Department of Neurology, Beth Israel Deaconess Medical Center, and Harvard Medical School, Boston, MA (M.F.)
| | - Guang-Xia Shi
- From the Department of Acupuncture and Moxibustion (X.-R.W., J.-W.Y., C.-S.J., X.-H.Z., G.-X.S., C.-Z.L.) and Beijing Institute of Tradition Chinese Medicine (X.-R.W.), Beijing Hospital of Traditional Chinese Medicine affiliated to Capital Medical University; Beijing Key Laboratory of Acupuncture Neuromodulation, China (X.-R.W., J.-W.Y., C.-S.J., X.-H.Z., G.-X.S., C.-Z.L.); and the Department of Neurology, Beth Israel Deaconess Medical Center, and Harvard Medical School, Boston, MA (M.F.)
| | - Marc Fisher
- From the Department of Acupuncture and Moxibustion (X.-R.W., J.-W.Y., C.-S.J., X.-H.Z., G.-X.S., C.-Z.L.) and Beijing Institute of Tradition Chinese Medicine (X.-R.W.), Beijing Hospital of Traditional Chinese Medicine affiliated to Capital Medical University; Beijing Key Laboratory of Acupuncture Neuromodulation, China (X.-R.W., J.-W.Y., C.-S.J., X.-H.Z., G.-X.S., C.-Z.L.); and the Department of Neurology, Beth Israel Deaconess Medical Center, and Harvard Medical School, Boston, MA (M.F.)
| | - Cun-Zhi Liu
- From the Department of Acupuncture and Moxibustion (X.-R.W., J.-W.Y., C.-S.J., X.-H.Z., G.-X.S., C.-Z.L.) and Beijing Institute of Tradition Chinese Medicine (X.-R.W.), Beijing Hospital of Traditional Chinese Medicine affiliated to Capital Medical University; Beijing Key Laboratory of Acupuncture Neuromodulation, China (X.-R.W., J.-W.Y., C.-S.J., X.-H.Z., G.-X.S., C.-Z.L.); and the Department of Neurology, Beth Israel Deaconess Medical Center, and Harvard Medical School, Boston, MA (M.F.).
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20
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Cheng PW, Lin YT, Ho WY, Lu PJ, Chen HH, Lai CC, Sun GC, Yeh TC, Hsiao M, Tseng CJ, Liu CP. Fructose induced neurogenic hypertension mediated by overactivation of p38 MAPK to impair insulin signaling transduction caused central insulin resistance. Free Radic Biol Med 2017; 112:298-307. [PMID: 28754499 DOI: 10.1016/j.freeradbiomed.2017.07.022] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/22/2017] [Revised: 07/20/2017] [Accepted: 07/22/2017] [Indexed: 10/19/2022]
Abstract
Type 2 diabetes are at a high risk of complications related to hypertension, and reports have indicated that insulin levels may be associated with blood pressure (BP). Fructose intake has recently been reported to promote insulin resistance and superoxide formation. The aim of this study is to investigate whether fructose intake can enhance superoxide generation and impair insulin signaling in the NTS and subsequently elevate BP in rats with fructose-induced hypertension. Treatment with fructose for 4 weeks increased the BP, serum fasting insulin, glucose, homeostatic model assessment-insulin resistance, and triglyceride levels and reduced the serum direct high-density lipoprotein level in the fructose group. The Tempol treatment recovered the fructose-induced decrease in nitric oxide production in the NTS. Immunoblotting and immunofluorescence analyses further showed that fructose increased the p38- and fructose-induced phosphorylation of insulin receptor substrate 1 (IRS1S307) and suppressed AktS473 and neuronal nitric oxide synthase phosphorylation. Similarly, fructose was able to impair insulin sensitivity and increase insulin levels in the NTS. Fructose intake also increased the production of superoxide in the NTS. The results of this study suggest that fructose might induce central insulin resistance and elevate BP by enhancing superoxide production and activating p38 phosphorylation in the NTS.
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Affiliation(s)
- Pei-Wen Cheng
- Department of Medical Education and Research, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan; Yuh-Ing Junior College of Health Care & Management, Kaohsiung, Taiwan
| | - Yu-Te Lin
- Section of Neurology, Kaohsiung Veterans General Hospital, Taiwan; Center for Geriatrics and Gerontology, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan
| | - Wen-Yu Ho
- Division of General Internal Medicine, Department of Internal Medicine, Kaohsiung Medical University Hospital, Taiwan
| | - Pei-Jung Lu
- Institute of Clinical Medicine, National Cheng-Kung University, Tainan, Taiwan
| | - Hsin-Hung Chen
- Department of Medical Education and Research, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan
| | - Chi-Cheng Lai
- Department of Internal Medicine, Division of Cardiology, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan
| | - Gwo-Ching Sun
- Department of Anesthesiology, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Tung-Chen Yeh
- Department of Internal Medicine, Division of Cardiology, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan
| | - Michael Hsiao
- Genomics Research Center, Academia Sinica, Taipei, Taiwan
| | - Ching-Jiunn Tseng
- Department of Medical Education and Research, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan; School of Medicine, National Yang-Ming University, Taipei, Taiwan; Department of Pharmacology, National Defense Medical Center, Taipei, Taiwan
| | - Chun-Peng Liu
- Department of Administration, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan; Section of Cardiology, Department of Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan.
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21
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Gao P, Ding XW, Dong L, Luo P, Zhang GH, Rong WF. Expression of aromatase in the rostral ventromedial medulla and its role in the regulation of visceral pain. CNS Neurosci Ther 2017; 23:980-989. [PMID: 29047208 DOI: 10.1111/cns.12769] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2017] [Revised: 09/22/2017] [Accepted: 09/25/2017] [Indexed: 12/30/2022] Open
Abstract
AIMS Estrogens are known to exert a wide spectrum of actions on brain functions including modulation of pain. Besides the circulating estrogens produced mainly by the ovaries, many brain regions are also capable of de novo synthesizing estrogens, which may exert important modulatory effects on neuronal functions. This study was aimed to test the hypothesis that aromatase, the enzyme that catalyzes the conversion of testosterone to estradiols, may be distributed in the rostral ventromedial medulla (RVM), where it may impact on visceral pain. METHODS AND RESULTS Adult female rats were treated with cyclophosphamide (CPM, 50 mg/kg, ip, once every 3 days) or saline. At approximately day 10 following the 3rd injection, CPM-treated rats exhibited colorectal hyperalgesia as they showed significantly greater abdominal withdrawal responses (AWR) to graded colorectal distension (CRD, 0-100 mm Hg) than the saline group. Immunofluorescent staining and Western blot assay revealed that CPM-induced colorectal hyperalgesia was associated with significantly increased expression of aromatase and phosphorylated μ-type opioid receptor (pMOR) and decreased expression of total MOR in the RVM. Intracisternal application of aromatase inhibitors, fadrozole, and letrozole reversed CPM-induced colorectal hyperalgesia and restored pMOR and MOR expression in the RVM. CONCLUSIONS Our observations confirmed the expression of aromatase in the RVM, a pivotal brain region in descending modulation of pain and opioid analgesia. The results support the hypothesis that locally produced estrogens in the RVM may be involved in the maintenance of chronic visceral hyperalgesia and the downstream signaling may involve phosphorylation of MOR.
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Affiliation(s)
- Po Gao
- Hongqiao International Institute of Medical Research, Tongren Hospital and Department of Physiology, Faculty of Basic Medical Sciences, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Xiao-Wei Ding
- Hongqiao International Institute of Medical Research, Tongren Hospital and Department of Physiology, Faculty of Basic Medical Sciences, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Li Dong
- Hongqiao International Institute of Medical Research, Tongren Hospital and Department of Physiology, Faculty of Basic Medical Sciences, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Ping Luo
- Hongqiao International Institute of Medical Research, Tongren Hospital and Department of Physiology, Faculty of Basic Medical Sciences, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Guo-Hua Zhang
- Hongqiao International Institute of Medical Research, Tongren Hospital and Department of Physiology, Faculty of Basic Medical Sciences, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Wei-Fang Rong
- Hongqiao International Institute of Medical Research, Tongren Hospital and Department of Physiology, Faculty of Basic Medical Sciences, Shanghai Jiaotong University School of Medicine, Shanghai, China.,Key Laboratory of Cerebrocranial Diseases, Ningxia Medical University, Yinchuan, China
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Majzúnová M, Pakanová Z, Kvasnička P, Bališ P, Čačányiová S, Dovinová I. Age-dependent redox status in the brain stem of NO-deficient hypertensive rats. J Biomed Sci 2017; 24:72. [PMID: 28893245 PMCID: PMC5594586 DOI: 10.1186/s12929-017-0366-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Accepted: 08/09/2017] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND The brain stem contains important nuclei that control cardiovascular function via the sympathetic nervous system (SNS), which is strongly influenced by nitric oxide. Its biological activity is also largely determined by oxygen free radicals. Despite many experimental studies, the role of AT1R-NAD(P)H oxidase-superoxide pathway in NO-deficiency is not yet sufficiently clarified. We determined changes in free radical signaling and antioxidant and detoxification response in the brain stem of young and adult Wistar rats during chronic administration of exogenous NO inhibitors. METHODS Young (4 weeks) and adult (10 weeks) Wistar rats were treated with 7-nitroindazole (7-NI group, 10 mg/kg/day), a specific nNOS inhibitor, with NG-nitro-L-arginine-methyl ester (L-NAME group, 50 mg/kg/day), a nonspecific NOS inhibitor, and with drinking water (Control group) during 6 weeks. Systolic blood pressure was measured by non-invasive plethysmography. Expression of genes (AT1R, AT2R, p22phox, SOD and NOS isoforms, HO-1, MDR1a, housekeeper GAPDH) was identified by real-time PCR. NOS activity was detected by conversion of [3H]-L-arginine to [3H]-L-citrulline and SOD activity was measured using UV VIS spectroscopy. RESULTS We observed a blood pressure elevation and decrease in NOS activity only after L-NAME application in both age groups. Gene expression of nNOS (youngs) and eNOS (adults) in the brain stem decreased after both inhibitors. The radical signaling pathway triggered by AT1R and p22phox was elevated in L-NAME adults, but not in young rats. Moreover, L-NAME-induced NOS inhibition increased antioxidant response, as indicated by the observed elevation of mRNA SOD3, HO-1, AT2R and MDR1a in adult rats. 7-NI did not have a significant effect on AT1R-NADPH oxidase-superoxide pathway, yet it affected antioxidant response of mRNA expression of SOD1 and stimulated total activity of SOD in young rats and mRNA expression of AT2R in adult rats. CONCLUSION Our results show that chronic NOS inhibition by two different NOS inhibitors has age-dependent effect on radical signaling and antioxidant/detoxificant response in Wistar rats. While 7-NI had neuroprotective effect in the brain stem of young Wistar rats, L-NAME- induced NOS inhibition evoked activation of AT1R-NAD(P)H oxidase pathway in adult Wistar rats. Triggering of the radical pathway was followed by activation of protective compensation mechanism at the gene expression level.
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Affiliation(s)
- Miroslava Majzúnová
- Institute of Normal and Pathological Physiology, Slovak Academy of Sciences, Sienkiewiczova 1, 813 71, Bratislava, Slovakia
| | - Zuzana Pakanová
- Institute of Chemistry, Slovak Academy of Sciences, Bratislava, Slovakia
| | - Peter Kvasnička
- Institute of Particle and Nuclear Physics, Faculty of Mathematics and Physics, Charles University, Prague, Czech Republic
| | - Peter Bališ
- Institute of Normal and Pathological Physiology, Slovak Academy of Sciences, Sienkiewiczova 1, 813 71, Bratislava, Slovakia
| | - Soňa Čačányiová
- Institute of Normal and Pathological Physiology, Slovak Academy of Sciences, Sienkiewiczova 1, 813 71, Bratislava, Slovakia
| | - Ima Dovinová
- Institute of Normal and Pathological Physiology, Slovak Academy of Sciences, Sienkiewiczova 1, 813 71, Bratislava, Slovakia.
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Daiber A, Di Lisa F, Oelze M, Kröller‐Schön S, Steven S, Schulz E, Münzel T. Crosstalk of mitochondria with NADPH oxidase via reactive oxygen and nitrogen species signalling and its role for vascular function. Br J Pharmacol 2017; 174:1670-1689. [PMID: 26660451 PMCID: PMC5446573 DOI: 10.1111/bph.13403] [Citation(s) in RCA: 183] [Impact Index Per Article: 26.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2015] [Revised: 09/22/2015] [Accepted: 11/30/2015] [Indexed: 12/21/2022] Open
Abstract
Cardiovascular diseases are associated with and/or caused by oxidative stress. This concept has been proven by using the approach of genetic deletion of reactive species producing (pro-oxidant) enzymes as well as by the overexpression of reactive species detoxifying (antioxidant) enzymes leading to a marked reduction of reactive oxygen and nitrogen species (RONS) and in parallel to an amelioration of the severity of diseases. Likewise, the development and progression of cardiovascular diseases is aggravated by overexpression of RONS producing enzymes as well as deletion of antioxidant RONS detoxifying enzymes. Thus, the consequences of the interaction (redox crosstalk) of superoxide/hydrogen peroxide produced by mitochondria with other ROS producing enzymes such as NADPH oxidases (Nox) are of outstanding importance and will be discussed including the consequences for endothelial nitric oxide synthase (eNOS) uncoupling as well as the redox regulation of the vascular function/tone in general (soluble guanylyl cyclase, endothelin-1, prostanoid synthesis). Pathways and potential mechanisms leading to this crosstalk will be analysed in detail and highlighted by selected examples from the current literature including hypoxia, angiotensin II-induced hypertension, nitrate tolerance, aging and others. The general concept of redox-based activation of RONS sources via "kindling radicals" and enzyme-specific "redox switches" will be discussed providing evidence that mitochondria represent key players and amplifiers of the burden of oxidative stress. LINKED ARTICLES This article is part of a themed section on Redox Biology and Oxidative Stress in Health and Disease. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v174.12/issuetoc.
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Affiliation(s)
- Andreas Daiber
- Center for Cardiology, Laboratory of Molecular CardiologyMedical Center of the Johannes Gutenberg UniversityMainzGermany
| | - Fabio Di Lisa
- Department of Biomedical SciencesUniversity of PadovaPadovaItaly
| | - Matthias Oelze
- Center for Cardiology, Laboratory of Molecular CardiologyMedical Center of the Johannes Gutenberg UniversityMainzGermany
| | - Swenja Kröller‐Schön
- Center for Cardiology, Laboratory of Molecular CardiologyMedical Center of the Johannes Gutenberg UniversityMainzGermany
| | - Sebastian Steven
- Center for Cardiology, Laboratory of Molecular CardiologyMedical Center of the Johannes Gutenberg UniversityMainzGermany
- Center of Thrombosis and HemostasisMedical Center of the Johannes Gutenberg UniversityMainzGermany
| | - Eberhard Schulz
- Center for Cardiology, Laboratory of Molecular CardiologyMedical Center of the Johannes Gutenberg UniversityMainzGermany
| | - Thomas Münzel
- Center for Cardiology, Laboratory of Molecular CardiologyMedical Center of the Johannes Gutenberg UniversityMainzGermany
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Sharma NM, Patel KP. Post-translational regulation of neuronal nitric oxide synthase: implications for sympathoexcitatory states. Expert Opin Ther Targets 2017; 21:11-22. [PMID: 27885874 PMCID: PMC5488701 DOI: 10.1080/14728222.2017.1265505] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Accepted: 11/23/2016] [Indexed: 12/20/2022]
Abstract
INTRODUCTION Nitric oxide (NO) synthesized via neuronal nitric oxide synthase (nNOS) plays a significant role in regulation/modulation of autonomic control of circulation. Various pathological states are associated with diminished nNOS expression and blunted autonomic effects of NO in the central nervous system (CNS) including heart failure, hypertension, diabetes mellitus, chronic renal failure etc. Therefore, elucidation of the molecular mechanism/s involved in dysregulation of nNOS is essential to understand the pathogenesis of increased sympathoexcitation in these diseased states. Areas covered: nNOS is a highly regulated enzyme, being regulated at transcriptional and posttranslational levels via protein-protein interactions and modifications viz. phosphorylation, ubiquitination, and sumoylation. The enzyme activity of nNOS also depends on the optimal concentration of substrate, cofactors and association with regulatory proteins. This review focuses on the posttranslational regulation of nNOS in the context of normal and diseased states within the CNS. Expert opinion: Gaining insight into the mechanism/s involved in the regulation of nNOS would provide novel strategies for manipulating nNOS directed therapeutic modalities in the future, including catalytically active dimer stabilization and protein-protein interactions with intracellular protein effectors. Ultimately, this is expected to provide tools to improve autonomic dysregulation in various diseases such as heart failure, hypertension, and diabetes.
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Affiliation(s)
- Neeru M Sharma
- a Department of Cellular & Integrative Physiology , University of Nebraska Medical Center , Omaha , NE , USA
| | - Kaushik P Patel
- a Department of Cellular & Integrative Physiology , University of Nebraska Medical Center , Omaha , NE , USA
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25
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Wu KLH, Wu CW, Tain YL, Chao YM, Hung CY, Tsai PC, Wang WS, Shih CD. Effects of high fructose intake on the development of hypertension in the spontaneously hypertensive rats: the role of AT 1R/gp91 PHOX signaling in the rostral ventrolateral medulla. J Nutr Biochem 2016; 41:73-83. [PMID: 28063367 DOI: 10.1016/j.jnutbio.2016.11.013] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2016] [Revised: 11/11/2016] [Accepted: 11/29/2016] [Indexed: 02/07/2023]
Abstract
Both genetic and dietary factors determine the development of hypertension. Whether dietary factor impacts the development of hereditary hypertension is unknown. Here, we evaluated the effect of daily high-fructose diet (HFD) on the development of hypertension in adolescent spontaneously hypertensive rats (SHR). Six-week-old SHR were randomly divided into two groups to receive HFD or normal diet (ND) for 3 weeks. The temporal profile of systolic blood pressure, alongside the sympathetic vasomotor activity, in the SHR-HFD showed significantly greater increases at 9-12 weeks of age compared with the age-matched SHR-ND group. Immunofluorescence was used to identify the distribution of reactive oxygen species (ROS), oxidants and antioxidants in rostral ventrolateral medulla (RVLM) where sympathetic premotor neurons reside. In RVLM of SHR-HFD, the levels of ROS accumulation and lipid peroxidation were elevated. The changes in protein expression were measured by Western blot. NADPH oxidase subunit gp91phox and angiotensin II type I receptor were up-regulated in RVLM neuron. On the other hand, the expression of extracellular superoxide dismutase was suppressed. Both molecular and hemodynamic changes in the SHR-HFD were rescued by oral pioglitazone treatment from weeks 7 to 9. Furthermore, central infusion with tempol, a ROS scavenger, effectively ameliorated ROS accumulation in RVLM and diminished the heightened pressor response and enhanced sympathetic activity in the SHR-HFD. Together, these results suggest that HFD intake at adolescent SHR may impact the development of hypertension via increasing oxidative stress in RVLM which could be effectively attenuated by pioglitazone treatment.
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Affiliation(s)
- Kay L H Wu
- Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, 83301, Taiwan, Republic of China; Department of Senior Citizen Services, National Tainan Institute of Nursing, Tainan 700, Taiwan, Republic of China.
| | - Chih-Wei Wu
- Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, 83301, Taiwan, Republic of China
| | - You-Lin Tain
- Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, 83301, Taiwan, Republic of China; Department of Pediatrics, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University, College of Medicine, Kaohsiung 833, Taiwan, Republic of China
| | - Yung-Mei Chao
- Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, 83301, Taiwan, Republic of China
| | - Chun-Ying Hung
- Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, 83301, Taiwan, Republic of China
| | - Pei-Chia Tsai
- Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, 83301, Taiwan, Republic of China
| | - Wei-Sing Wang
- Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, 83301, Taiwan, Republic of China
| | - Cheng-Dean Shih
- Department of Pharmacy, Graduate Institute of Pharmaceutical Technology, Tajen University, Pingtung County 90741, Taiwan, Republic of China.
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KVANDOVÁ M, MAJZÚNOVÁ M, DOVINOVÁ I. The Role of PPARγ in Cardiovascular Diseases. Physiol Res 2016; 65:S343-S363. [DOI: 10.33549/physiolres.933439] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The peroxisome proliferator-activated receptors (PPAR) belong to the nuclear superfamily of ligand-activated transcription factors. PPARγ acts as a nutrient sensor that regulates several homeostatic functions. Its disruption can lead to vascular pathologies, disorders of fatty acid/lipid metabolism and insulin resistance. PPARγ can modulate several signaling pathways connected with blood pressure regulation. Firstly, it affects the insulin signaling pathway and endothelial dysfunction by modulation of expression and/or phosphorylation of signaling molecules through the PI3K/Akt/eNOS or MAPK/ET-1 pathways. Secondly, it can modulate gene expression of the renin- angiotensin system – cascade proteins, which potentially slow down the progression of atherosclerosis and hypertension. Thirdly, it can modulate oxidative stress response either directly through PPAR or indirectly through Nrf2 activation. In this context, activation and functioning of PPARγ is very important in the regulation of several disorders such as diabetes mellitus, hypertension and/or metabolic syndrome.
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Affiliation(s)
| | | | - I. DOVINOVÁ
- Institute of Normal and Pathological Physiology, Slovak Academy of Sciences, Bratislava, Slovakia
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27
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Wu KLH, Wu CW, Chao YM, Hung CY, Chan JYH. Impaired Nrf2 regulation of mitochondrial biogenesis in rostral ventrolateral medulla on hypertension induced by systemic inflammation. Free Radic Biol Med 2016; 97:58-74. [PMID: 27223823 DOI: 10.1016/j.freeradbiomed.2016.05.012] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Revised: 05/04/2016] [Accepted: 05/14/2016] [Indexed: 12/30/2022]
Abstract
Oxidative stress in rostral ventrolateral medulla (RVLM), where sympathetic premotor neurons reside, is involved in the development of hypertension under systemic inflammation. Mitochondrial dysfunction contributes to tissue oxidative stress. In this study, we sought to investigate whether hypertension developed under systemic inflammation is attributable to impaired mitochondrial biogenesis in RVLM. In normotensive Sprague-Dawley rats, intraperitoneal infusion of a low dose Escherichia coli lipopolysaccharide (LPS) for 7 days promoted a pressor response, alongside a decrease in mitochondrial DNA (mtDNA) copy number, reductions in protein expression of nuclear DNA-encoded transcription factors for mitochondrial biogenesis, including mitochondrial transcription factor A (TFAM) and nuclear factor erythroid-derived 2-like 2 (Nrf2), and suppression of nuclear translocation of the phosphorylated Nrf2 (p-Nrf2) in RVLM neurons; all of which were abrogated by treatment with intracisternal infusion of an interleukin-1β (IL-1β) blocker, IL-1Ra, or a mobile mitochondrial electron carrier, coenzyme Q10 (CoQ10). Microinjection into RVLM of IL-1β suppressed the expressions of p-Nrf2 and TFAM, and evoked a pressor response; conversely, the Nrf2 inducer, tert-butylhydroquinone, lessened the LPS-induced suppression of TFAM expression and pressor response. At cellular level, exposure of neuronal N2a cells to IL-1β decreased mtDNA copy number, increased protein interaction of Nrf2 to its negative regulator, kelch-like ECH-associated protein 1 (Keap1), and reduced DNA binding activity of p-Nrf2 to Tfam gene. Together these results indicate that defect mitochondrial biogenesis in RVLM neurons entailing redox-sensitive and IL-1β-dependent suppression of TFAM because of the increase in the formation of Keap1/Nrf2 complex, reductions in nuclear translocation of the activated Nrf2 and its binding to the Tfam gene promoter may underlie hypertension developed under the LPS-induced systemic inflammation.
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Affiliation(s)
- Kay L H Wu
- Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung 83301, Taiwan
| | - Chih-Wei Wu
- Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung 83301, Taiwan
| | - Yung-Mei Chao
- Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung 83301, Taiwan
| | - Chun-Ying Hung
- Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung 83301, Taiwan
| | - Julie Y H Chan
- Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung 83301, Taiwan.
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28
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Tain YL, Lee WC, Leu S, Wu K, Chan J. High salt exacerbates programmed hypertension in maternal fructose-fed male offspring. Nutr Metab Cardiovasc Dis 2015; 25:1146-1151. [PMID: 26607702 DOI: 10.1016/j.numecd.2015.08.002] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/06/2015] [Revised: 06/07/2015] [Accepted: 08/11/2015] [Indexed: 12/19/2022]
Abstract
BACKGROUND AND AIMS Consumption of food and drinks containing high fructose (HF), which is associated with hypertension, is increasing steeply. Moreover, increased salt intake significantly increases hypertension risk. We examined whether maternal HF and postnatal high salt (HS) intake had synergistic effects on blood pressure (BP) elevation in adult offspring and determined the underlying mechanisms. METHODS AND RESULTS Pregnant Sprague-Dawley rats received regular chow or chow supplemented with 60% fructose during the entire pregnancy and lactation periods. Half of the male offspring received 1% NaCl in drinking water from weaning to 3 months of age. Male offspring were assigned to 4 groups (control, HF, HS, and HF + HS) and were sacrificed at 12 weeks of age. Offspring in HF and HS groups developed hypertension, indicating that HF and HS synergistically increased BP. Postnatal HS intake increased Ace expression and decreased Agtr1b and Mas1 expression in the kidneys. Renal mRNA levels of Ace and Agtr1a were significantly higher in HF + HS group than in control group. Renal levels of Na-K-2Cl cotransporter, type 3 sodium hydrogen exchanger, and Na(+)/Cl(-) cotransporter were higher in HS and HF + HS groups than in control group. CONCLUSION Postnatal HS intake exacerbated prenatal HF-induced programmed hypertension. HF and HS induced programmed hypertension by differentially inducing renin-angiotensin system and sodium transporters in the kidneys. Better understanding of the effect of the relationship between HF and HS on hypertension development will help prevent hypertension in mothers and children exposed to HF and HS.
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Affiliation(s)
- Y-L Tain
- Department of Pediatrics, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University, College of Medicine, Taiwan; Center for Translational Research in Biomedical Sciences, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University, College of Medicine, Kaohsiung, Taiwan
| | - W-C Lee
- Department of Urology, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University, College of Medicine, Taiwan
| | - S Leu
- Center for Translational Research in Biomedical Sciences, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University, College of Medicine, Kaohsiung, Taiwan
| | - K Wu
- Center for Translational Research in Biomedical Sciences, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University, College of Medicine, Kaohsiung, Taiwan
| | - J Chan
- Center for Translational Research in Biomedical Sciences, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University, College of Medicine, Kaohsiung, Taiwan.
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Rezq S, Abdel-Rahman AA. Central GPR109A Activation Mediates Glutamate-Dependent Pressor Response in Conscious Rats. J Pharmacol Exp Ther 2015; 356:456-65. [PMID: 26621144 DOI: 10.1124/jpet.115.229146] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2015] [Accepted: 11/02/2015] [Indexed: 12/11/2022] Open
Abstract
G protein-coupled receptor 109A (GPR109A) activation by its ligand nicotinic acid (NA) in immune cells increases Ca(2+) levels, and Ca(2+) induces glutamate release and oxidative stress in central blood pressure (BP)-regulating nuclei, for example, the rostral ventrolateral medulla (RVLM), leading to sympathoexcitation. Despite NA's ability to reach the brain, the expression and function of its receptor GPR109A in the RVLM remain unknown. We hypothesized that NA activation of RVLM GPR109A causes Ca(2+)-dependent l-glutamate release and subsequently increases neuronal oxidative stress, sympathetic activity, and BP. To test this hypothesis, we adopted a multilevel approach, which included pharmacologic in vivo studies along with ex vivo and in vitro molecular studies in rat pheochromocytoma cell line (PC12) cells (which exhibit neuronal phenotype). We present the first evidence for GPR109A expression in the RVLM and in PC12 cells. Next, we showed that RVLM GPR109A activation (NA) caused pressor and bradycardic responses in conscious rats. The resemblance of these responses to those caused by intra-RVLM glutamate and their attenuation by NMDA receptor (NMDAR) blockade (2-amino-5-phosphonopentanoic acid) and enhancement by l-glutamate uptake inhibition (l-trans-pyrrolidine-2,4-dicarboxylic acid, PDC) supported our hypothesis. NA increased Ca(2+), glutamate, nitric oxide and reactive oxygen species (ROS) levels in PC12 cells and increased RVLM ROS levels. The inactive NA analog isonicotinic acid failed to replicate the cardiovascular and biochemical effects of NA. Further, GPR109A knockdown (siRNA) abrogated the biochemical effects of NA in PC12 cells. These novel findings yield new insight into the role of RVLM GPR109A in central BP control.
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Affiliation(s)
- Samar Rezq
- Department of Pharmacology, School of Medicine, East Carolina University, North Carolina
| | - Abdel A Abdel-Rahman
- Department of Pharmacology, School of Medicine, East Carolina University, North Carolina
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30
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Yu Y, Xue BJ, Wei SG, Zhang ZH, Beltz TG, Guo F, Johnson AK, Felder RB. Activation of central PPAR-γ attenuates angiotensin II-induced hypertension. Hypertension 2015; 66:403-11. [PMID: 26101342 DOI: 10.1161/hypertensionaha.115.05726] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2015] [Accepted: 05/20/2015] [Indexed: 01/17/2023]
Abstract
Inflammation and renin-angiotensin system activity in the brain contribute to hypertension through effects on fluid intake, vasopressin release, and sympathetic nerve activity. We recently reported that activation of brain peroxisome proliferator-activated receptor (PPAR)-γ in heart failure rats reduced inflammation and renin-angiotensin system activity in the hypothalamic paraventricular nucleus and ameliorated the peripheral manifestations of heart failure. We hypothesized that the activation of brain PPAR-γ might have beneficial effects in angiotensin II-induced hypertension. Sprague-Dawley rats received a 2-week subcutaneous infusion of angiotensin II (120 ng/kg per minute) combined with a continuous intracerebroventricular infusion of vehicle, the PPAR-γ agonist pioglitazone (3 nmol/h) or the PPAR-γ antagonist GW9662 (7 nmol/h). Angiotensin II+vehicle rats had increased mean blood pressure, increased sympathetic drive as indicated by the mean blood pressure response to ganglionic blockade, and increased water consumption. PPAR-γ mRNA in subfornical organ and hypothalamic paraventricular nucleus was unchanged, but PPAR-γ DNA-binding activity was reduced. mRNA for interleukin-1β, tumor necrosis factor-α, cyclooxygenase-2, and angiotensin II type 1 receptor was augmented in both nuclei, and hypothalamic paraventricular nucleus neuronal activity was increased. The plasma vasopressin response to a 6-hour water restriction also increased. These responses to angiotensin II were exacerbated by GW9662 and ameliorated by pioglitazone, which increased PPAR-γ mRNA and PPAR-γ DNA-binding activity in subfornical organ and hypothalamic paraventricular nucleus. Pioglitazone and GW9662 had no effects on control rats. The results suggest that activating brain PPAR-γ to reduce central inflammation and brain renin-angiotensin system activity may be a useful adjunct in the treatment of angiotensin II-dependent hypertension.
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Affiliation(s)
- Yang Yu
- From the Department of Internal Medicine, Roy J and Lucille A Carver College of Medicine (Y.Y., S.-G.W., Z.-H.Z., R.B.F.) and Department of Psychological and Brain Sciences (B.-.J.X., T.G.B., F.G., A.K.J.), University of Iowa, Iowa City; and Research Service, Veterans Affairs Medical Center, Iowa City, IA (R.B.F.)
| | - Bao-Jian Xue
- From the Department of Internal Medicine, Roy J and Lucille A Carver College of Medicine (Y.Y., S.-G.W., Z.-H.Z., R.B.F.) and Department of Psychological and Brain Sciences (B.-.J.X., T.G.B., F.G., A.K.J.), University of Iowa, Iowa City; and Research Service, Veterans Affairs Medical Center, Iowa City, IA (R.B.F.)
| | - Shun-Guang Wei
- From the Department of Internal Medicine, Roy J and Lucille A Carver College of Medicine (Y.Y., S.-G.W., Z.-H.Z., R.B.F.) and Department of Psychological and Brain Sciences (B.-.J.X., T.G.B., F.G., A.K.J.), University of Iowa, Iowa City; and Research Service, Veterans Affairs Medical Center, Iowa City, IA (R.B.F.)
| | - Zhi-Hua Zhang
- From the Department of Internal Medicine, Roy J and Lucille A Carver College of Medicine (Y.Y., S.-G.W., Z.-H.Z., R.B.F.) and Department of Psychological and Brain Sciences (B.-.J.X., T.G.B., F.G., A.K.J.), University of Iowa, Iowa City; and Research Service, Veterans Affairs Medical Center, Iowa City, IA (R.B.F.)
| | - Terry G Beltz
- From the Department of Internal Medicine, Roy J and Lucille A Carver College of Medicine (Y.Y., S.-G.W., Z.-H.Z., R.B.F.) and Department of Psychological and Brain Sciences (B.-.J.X., T.G.B., F.G., A.K.J.), University of Iowa, Iowa City; and Research Service, Veterans Affairs Medical Center, Iowa City, IA (R.B.F.)
| | - Fang Guo
- From the Department of Internal Medicine, Roy J and Lucille A Carver College of Medicine (Y.Y., S.-G.W., Z.-H.Z., R.B.F.) and Department of Psychological and Brain Sciences (B.-.J.X., T.G.B., F.G., A.K.J.), University of Iowa, Iowa City; and Research Service, Veterans Affairs Medical Center, Iowa City, IA (R.B.F.)
| | - Alan Kim Johnson
- From the Department of Internal Medicine, Roy J and Lucille A Carver College of Medicine (Y.Y., S.-G.W., Z.-H.Z., R.B.F.) and Department of Psychological and Brain Sciences (B.-.J.X., T.G.B., F.G., A.K.J.), University of Iowa, Iowa City; and Research Service, Veterans Affairs Medical Center, Iowa City, IA (R.B.F.)
| | - Robert B Felder
- From the Department of Internal Medicine, Roy J and Lucille A Carver College of Medicine (Y.Y., S.-G.W., Z.-H.Z., R.B.F.) and Department of Psychological and Brain Sciences (B.-.J.X., T.G.B., F.G., A.K.J.), University of Iowa, Iowa City; and Research Service, Veterans Affairs Medical Center, Iowa City, IA (R.B.F.).
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