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Martins FDAD, Mateo DPA, Silva FJDM, Moura SSD, Oliveira EC, Coelho DB, Bearzoti E, Pinto KMDC, Becker LK. Use of Diuretics is Associated with Higher Risk of Sarcopenia in Older Adults with Hypertension. INTERNATIONAL JOURNAL OF CARDIOVASCULAR SCIENCES 2022. [DOI: 10.36660/ijcs.20200279] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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Neumann J, Boknik P, Kirchhefer U, Gergs U. The role of PP5 and PP2C in cardiac health and disease. Cell Signal 2021; 85:110035. [PMID: 33964402 DOI: 10.1016/j.cellsig.2021.110035] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Revised: 04/16/2021] [Accepted: 05/03/2021] [Indexed: 02/08/2023]
Abstract
Protein phosphatases are important, for example, as functional antagonists of β-adrenergic stimulation of the mammalian heart. While β-adrenergic stimulations increase the phosphorylation state of regulatory proteins and therefore force of contraction in the heart, these phosphorylations are reversed and thus force is reduced by the activity of protein phosphatases. In this context the role of PP5 and PP2C is starting to unravel. They do not belong to the same family of phosphatases with regard to sequence homology, many similarities with regard to location, activation by lipids and putative substrates have been worked out over the years. We also suggest which pathways for regulation of PP5 and/or PP2C described in other tissues and not yet in the heart might be useful to look for in cardiac tissue. Both phosphatases might play a role in signal transduction of sarcolemmal receptors in the heart. Expression of PP5 and PP2C can be increased by extracellular stimuli in the heart. Because PP5 is overexpressed in failing animal and human hearts, and because overexpression of PP5 or PP2C leads to cardiac hypertrophy and KO of PP5 leads to cardiac hypotrophy, one might argue for a role of PP5 and PP2C in heart failure. Because PP5 and PP2C can reduce, at least in vitro, the phosphorylation state of proteins thought to be relevant for cardiac arrhythmias, a role of these phosphatases for cardiac arrhythmias is also probable. Thus, PP5 and PP2C might be druggable targets to treat important cardiac diseases like heart failure, cardiac hypertrophy and cardiac arrhythmias.
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Affiliation(s)
- Joachim Neumann
- Institut für Pharmakologie und Toxikologie, Medizinische Fakultät, Martin-Luther-Universität Halle-Wittenberg, Magdeburger Str. 4, D-06097 Halle, Germany.
| | - Peter Boknik
- Institut für Pharmakologie und Toxikologie, Medizinische Fakultät, Westfälische Wilhelms-Universität, Domagkstraße 12, D-48149 Münster, Germany.
| | - Uwe Kirchhefer
- Institut für Pharmakologie und Toxikologie, Medizinische Fakultät, Westfälische Wilhelms-Universität, Domagkstraße 12, D-48149 Münster, Germany.
| | - Ulrich Gergs
- Institut für Pharmakologie und Toxikologie, Medizinische Fakultät, Martin-Luther-Universität Halle-Wittenberg, Magdeburger Str. 4, D-06097 Halle, Germany.
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Bollmann P, Werner F, Jaron M, Bruns TA, Wache H, Runte J, Boknik P, Kirchhefer U, Müller FU, Buchwalow IB, Rothemund S, Neumann J, Gergs U. Initial Characterization of Stressed Transgenic Mice With Cardiomyocyte-Specific Overexpression of Protein Phosphatase 2C. Front Pharmacol 2021; 11:591773. [PMID: 33597873 PMCID: PMC7883593 DOI: 10.3389/fphar.2020.591773] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Accepted: 12/07/2020] [Indexed: 12/17/2022] Open
Abstract
As part of our ongoing studies on the potential pathophysiological role of serine/threonine phosphatases (PP) in the mammalian heart, we have generated mice with cardiac-specific overexpression of PP2Cβ (PP2C-TG) and compared them with littermate wild type mice (WT) serving as a control. Cardiac fibrosis was noted histologically in PP2C-TG. Collagen 1a, interleukin-6 and the natriuretic peptides ANP and BNP were augmented in PP2C-TG vs. WT (p < 0.05). Left atrial preparations from PP2C-TG were less resistant to hypoxia than atria from WT. PP2C-TG maintained cardiac function after the injection of lipopolysaccharide (LPS, a model of sepsis) and chronic isoproterenol treatment (a model of heart failure) better than WT. Crossbreeding of PP2C-TG mice with PP2A-TG mice (a genetic model of heart failure) resulted in double transgenic (DT) mice that exhibited a pronounced increase of heart weight in contrast to the mild hypertrophy noted in the mono-transgenic mice. The ejection fraction was reduced in PP2C-TG and in PP2A-TG mice compared with WT, but the reduction was the highest in DT compared with WT. PP2A enzyme activity was enhanced in PP2A-TG and DT mice compared with WT and PP2C-TG mice. In summary, cardiac overexpression of PP2Cβ and co-overexpression of both the catalytic subunit of PP2A and PP2Cβ were detrimental to cardiac function. PP2Cβ overexpression made cardiac preparations less resistant to hypoxia than WT, leading to fibrosis, but PP2Cβ overexpression led to better adaptation to some stressors, such as LPS or chronic β-adrenergic stimulation. Hence, the effect of PP2Cβ is context sensitive.
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Affiliation(s)
- Paula Bollmann
- Institut für Pharmakologie und Toxikologie, Medizinische Fakultät, Martin-Luther-Universität Halle-Wittenberg, Halle, Germany
| | - Franziska Werner
- Institut für Pharmakologie und Toxikologie, Medizinische Fakultät, Martin-Luther-Universität Halle-Wittenberg, Halle, Germany
| | - Marko Jaron
- Institut für Pharmakologie und Toxikologie, Medizinische Fakultät, Martin-Luther-Universität Halle-Wittenberg, Halle, Germany
| | - Tom A Bruns
- Institut für Pharmakologie und Toxikologie, Medizinische Fakultät, Martin-Luther-Universität Halle-Wittenberg, Halle, Germany
| | - Hartmut Wache
- Institut für Pharmakologie und Toxikologie, Medizinische Fakultät, Martin-Luther-Universität Halle-Wittenberg, Halle, Germany
| | - Jochen Runte
- Institut für Pharmakologie und Toxikologie, Medizinische Fakultät, Martin-Luther-Universität Halle-Wittenberg, Halle, Germany
| | - Peter Boknik
- Institut für Pharmakologie und Toxikologie, Medizinische Fakultät, Westfälische Wilhelms-Universität, Münster, Germany
| | - Uwe Kirchhefer
- Institut für Pharmakologie und Toxikologie, Medizinische Fakultät, Westfälische Wilhelms-Universität, Münster, Germany
| | - Frank U Müller
- Institut für Pharmakologie und Toxikologie, Medizinische Fakultät, Westfälische Wilhelms-Universität, Münster, Germany
| | | | | | - Joachim Neumann
- Institut für Pharmakologie und Toxikologie, Medizinische Fakultät, Martin-Luther-Universität Halle-Wittenberg, Halle, Germany
| | - Ulrich Gergs
- Institut für Pharmakologie und Toxikologie, Medizinische Fakultät, Martin-Luther-Universität Halle-Wittenberg, Halle, Germany
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4
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Hord JM, Garcia MM, Farris KR, Guzzoni V, Lee Y, Lawler MS, Lawler JM. Nox2 signaling and muscle fiber remodeling are attenuated by losartan administration during skeletal muscle unloading. Physiol Rep 2021; 9:e14606. [PMID: 33400850 PMCID: PMC7785102 DOI: 10.14814/phy2.14606] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Accepted: 09/20/2020] [Indexed: 12/21/2022] Open
Abstract
Reduced mechanical loading results in atrophy of skeletal muscle fibers. Increased reactive oxygen species (ROS) are causal in sarcolemmal dislocation of nNOS and FoxO3a activation. The Nox2 isoform of NADPH oxidase and mitochondria release ROS during disuse in skeletal muscle. Activation of the angiotensin II type 1 receptor (AT1R) can elicit Nox2 complex formation. The AT1R blocker losartan was used to test the hypothesis that AT1R activation drives Nox2 assembly, nNOS dislocation, FoxO3a activation, and thus alterations in morphology in the unloaded rat soleus. Male Fischer 344 rats were divided into four groups: ambulatory control (CON), ambulatory + losartan (40 mg kg-1 day-1 ) (CONL), 7 days of tail-traction hindlimb unloading (HU), and HU + losartan (HUL). Losartan attenuated unloading-induced loss of muscle fiber cross-sectional area (CSA) and fiber-type shift. Losartan mitigated unloading-induced elevation of ROS levels and upregulation of Nox2. Furthermore, AT1R blockade abrogated nNOS dislocation away from the sarcolemma and elevation of nuclear FoxO3a. We conclude that AT1R blockade attenuates disuse remodeling by inhibiting Nox2, thereby lessening nNOS dislocation and activation of FoxO3a.
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Affiliation(s)
- Jeffrey M Hord
- Redox Biology & Cell Signaling Laboratory, Department of Health and Kinesiology, Graduate Faculty of Nutrition, Texas A&M University, College Station, TX, USA
| | - Marcela M Garcia
- Redox Biology & Cell Signaling Laboratory, Department of Health and Kinesiology, Graduate Faculty of Nutrition, Texas A&M University, College Station, TX, USA
| | - Katherine R Farris
- Redox Biology & Cell Signaling Laboratory, Department of Health and Kinesiology, Graduate Faculty of Nutrition, Texas A&M University, College Station, TX, USA
| | - Vinicius Guzzoni
- Department of Cellular and Molecular Biology, Federal University of Paraíba, João Pessoa, Paraíba, Brazil
| | - Yang Lee
- Department of Systems Biology and Translational Medicine, Texas A&M Health Science Center College of Medicine, College Station/Temple, TX, USA
| | - Matthew S Lawler
- Redox Biology & Cell Signaling Laboratory, Department of Health and Kinesiology, Graduate Faculty of Nutrition, Texas A&M University, College Station, TX, USA.,Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA, USA
| | - John M Lawler
- Redox Biology & Cell Signaling Laboratory, Department of Health and Kinesiology, Graduate Faculty of Nutrition, Texas A&M University, College Station, TX, USA
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Yoshida T, Delafontaine P. Mechanisms of IGF-1-Mediated Regulation of Skeletal Muscle Hypertrophy and Atrophy. Cells 2020; 9:cells9091970. [PMID: 32858949 PMCID: PMC7564605 DOI: 10.3390/cells9091970] [Citation(s) in RCA: 256] [Impact Index Per Article: 64.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Revised: 08/18/2020] [Accepted: 08/19/2020] [Indexed: 12/18/2022] Open
Abstract
Insulin-like growth factor-1 (IGF-1) is a key growth factor that regulates both anabolic and catabolic pathways in skeletal muscle. IGF-1 increases skeletal muscle protein synthesis via PI3K/Akt/mTOR and PI3K/Akt/GSK3β pathways. PI3K/Akt can also inhibit FoxOs and suppress transcription of E3 ubiquitin ligases that regulate ubiquitin proteasome system (UPS)-mediated protein degradation. Autophagy is likely inhibited by IGF-1 via mTOR and FoxO signaling, although the contribution of autophagy regulation in IGF-1-mediated inhibition of skeletal muscle atrophy remains to be determined. Evidence has suggested that IGF-1/Akt can inhibit muscle atrophy-inducing cytokine and myostatin signaling via inhibition of the NF-κΒ and Smad pathways, respectively. Several miRNAs have been found to regulate IGF-1 signaling in skeletal muscle, and these miRs are likely regulated in different pathological conditions and contribute to the development of muscle atrophy. IGF-1 also potentiates skeletal muscle regeneration via activation of skeletal muscle stem (satellite) cells, which may contribute to muscle hypertrophy and/or inhibit atrophy. Importantly, IGF-1 levels and IGF-1R downstream signaling are suppressed in many chronic disease conditions and likely result in muscle atrophy via the combined effects of altered protein synthesis, UPS activity, autophagy, and muscle regeneration.
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Affiliation(s)
- Tadashi Yoshida
- Heart and Vascular Institute, John W. Deming Department of Medicine, Tulane University School of Medicine, 1430 Tulane Ave SL-48, New Orleans, LA 70112, USA
- Department of Physiology, Tulane University School of Medicine, 1430 Tulane Ave, New Orleans, LA 70112, USA
- Correspondence: (T.Y.); (P.D.)
| | - Patrice Delafontaine
- Heart and Vascular Institute, John W. Deming Department of Medicine, Tulane University School of Medicine, 1430 Tulane Ave SL-48, New Orleans, LA 70112, USA
- Department of Physiology, Tulane University School of Medicine, 1430 Tulane Ave, New Orleans, LA 70112, USA
- Correspondence: (T.Y.); (P.D.)
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Xie T, Chen C, Peng Z, Brown BC, Reisz JA, Xu P, Zhou Z, Song A, Zhang Y, Bogdanov MV, Kellems RE, D'Alessandro A, Zhang W, Xia Y. Erythrocyte Metabolic Reprogramming by Sphingosine 1-Phosphate in Chronic Kidney Disease and Therapies. Circ Res 2020; 127:360-375. [PMID: 32284030 DOI: 10.1161/circresaha.119.316298] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
RATIONALE Hypoxia promotes renal damage and progression of chronic kidney disease (CKD). The erythrocyte is the only cell type for oxygen (O2) delivery. Sphingosine 1-phosphate (S1P)-a highly enriched biolipid in erythrocytes-is recently reported to be induced under high altitude in normal humans to enhance O2 delivery. However, nothing is known about erythrocyte S1P in CKD. OBJECTIVE To investigate the function and metabolic basis of erythrocyte S1P in CKD with a goal to explore potential therapeutics. METHODS AND RESULTS Using erythrocyte-specific SphK1 (sphingosine kinase 1; the only enzyme to produce S1P in erythrocytes) knockout mice (eSphK1-/-) in an experimental model of hypertensive CKD with Ang II (angiotensin II) infusion, we found severe renal hypoxia, hypertension, proteinuria, and fibrosis in Ang II-infused eSphk1-/- mice compared with controls. Untargeted metabolomics profiling and in vivo U-13C6 isotopically labeled glucose flux analysis revealed that SphK1 is required for channeling glucose metabolism toward glycolysis versus pentose phosphate pathway, resulting in enhanced erythroid-specific Rapoport-Luebering shunt in Ang II-infused mice. Mechanistically, increased erythrocyte S1P functioning intracellularly activates AMPK (AMP-activated protein kinase) 1α and BPGM (bisphosphoglycerate mutase) by reducing ceramide/S1P ratio and inhibiting PP2A (protein phosphatase 2A), leading to increased 2,3-bisphosphoglycerate (an erythrocyte-specific metabolite negatively regulating Hb [hemoglobin]-O2-binding affinity) production and thus more O2 delivery to counteract kidney hypoxia and progression to CKD. Preclinical studies revealed that an AMPK agonist or a PP2A inhibitor rescued the severe CKD phenotype in Ang II-infused eSphK1-/- mice and prevented development of CKD in the control mice by inducing 2,3-bisphosphoglycerate production and thus enhancing renal oxygenation. Translational research validated mouse findings in erythrocytes of hypertensive CKD patients and cultured human erythrocytes. CONCLUSIONS Our study elucidates the beneficial role of eSphk1-S1P in hypertensive CKD by channeling glucose metabolism toward Rapoport-Luebering shunt and inducing 2,3-bisphosphoglycerate production and O2 delivery via a PP2A-AMPK1α signaling pathway. These findings reveal the metabolic and molecular basis of erythrocyte S1P in CKD and new therapeutic avenues.
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Affiliation(s)
- Tingting Xie
- From the Rheumatology and Immunology (T.X.), Xiangya Hospital, Central South University, Changsha, Hunan, China.,Biochemistry and Molecular Biology (T.X., C.C., P.X., A.S., Y.Z., M.V.B., R.E.K., W.Z., Y.X.), University of Texas McGovern Medical School at Houston
| | - Changhan Chen
- Otolaryngology Head and Neck Surgery (C.C.), Xiangya Hospital, Central South University, Changsha, Hunan, China.,Biochemistry and Molecular Biology (T.X., C.C., P.X., A.S., Y.Z., M.V.B., R.E.K., W.Z., Y.X.), University of Texas McGovern Medical School at Houston
| | - Zhangzhe Peng
- Nephrology (Z.P.), Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Benjamin C Brown
- Department of Biochemistry and Molecular Genetics, University of Colorado School of Medicine, Aurora (B.C.B., J.A.R., A.D.)
| | - Julie A Reisz
- Department of Biochemistry and Molecular Genetics, University of Colorado School of Medicine, Aurora (B.C.B., J.A.R., A.D.)
| | - Ping Xu
- Biochemistry and Molecular Biology (T.X., C.C., P.X., A.S., Y.Z., M.V.B., R.E.K., W.Z., Y.X.), University of Texas McGovern Medical School at Houston
| | - Zhen Zhou
- Division of Medical Genetics, Department of Internal Medicine (Z.Z.), University of Texas McGovern Medical School at Houston
| | - Anren Song
- Biochemistry and Molecular Biology (T.X., C.C., P.X., A.S., Y.Z., M.V.B., R.E.K., W.Z., Y.X.), University of Texas McGovern Medical School at Houston
| | - Yujin Zhang
- Biochemistry and Molecular Biology (T.X., C.C., P.X., A.S., Y.Z., M.V.B., R.E.K., W.Z., Y.X.), University of Texas McGovern Medical School at Houston
| | - Mikhail V Bogdanov
- Biochemistry and Molecular Biology (T.X., C.C., P.X., A.S., Y.Z., M.V.B., R.E.K., W.Z., Y.X.), University of Texas McGovern Medical School at Houston
| | - Rodney E Kellems
- Biochemistry and Molecular Biology (T.X., C.C., P.X., A.S., Y.Z., M.V.B., R.E.K., W.Z., Y.X.), University of Texas McGovern Medical School at Houston.,MDAnderson-UTHealth Graduate School of Biomedical Science, Houston, TX (R.E.K., Y.X.)
| | - Angelo D'Alessandro
- Department of Biochemistry and Molecular Genetics, University of Colorado School of Medicine, Aurora (B.C.B., J.A.R., A.D.)
| | - Weiru Zhang
- General Medicine (W.Z.), Xiangya Hospital, Central South University, Changsha, Hunan, China.,Biochemistry and Molecular Biology (T.X., C.C., P.X., A.S., Y.Z., M.V.B., R.E.K., W.Z., Y.X.), University of Texas McGovern Medical School at Houston
| | - Yang Xia
- Biochemistry and Molecular Biology (T.X., C.C., P.X., A.S., Y.Z., M.V.B., R.E.K., W.Z., Y.X.), University of Texas McGovern Medical School at Houston.,MDAnderson-UTHealth Graduate School of Biomedical Science, Houston, TX (R.E.K., Y.X.)
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Liu Y, Bi X, Zhang Y, Wang Y, Ding W. Mitochondrial dysfunction/NLRP3 inflammasome axis contributes to angiotensin II-induced skeletal muscle wasting via PPAR-γ. J Transl Med 2020; 100:712-726. [PMID: 31857693 DOI: 10.1038/s41374-019-0355-1] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2019] [Revised: 10/19/2019] [Accepted: 11/04/2019] [Indexed: 12/15/2022] Open
Abstract
Angiotensin II (Ang II) levels are elevated in patients with chronic kidney disease or heart failure, and directly causes skeletal muscle wasting in rodents, but the molecular mechanisms of Ang II-induced skeletal muscle wasting and its potential as a therapeutic target are unknown. We investigated the NLR family pyrin domain containing 3 (NLRP3) inflammasome-mediated muscle atrophy response to Ang II in C2C12 myotubes and Nlrp3 knockout mice. We also assessed the mitochondrial dysfunction (MtD)/NLRP3 inflammasome axis in Ang II-induced C2C12 myotubes. Finally, we examined whether a peroxisome proliferator-activated receptor-γ (PPAR-γ) agonist could attenuate skeletal muscle wasting by targeting the MtD/NLRP3 inflammasome axis in vitro and in vivo. We demonstrated that Ang II increased NLRP3 inflammasome activation in cultured C2C12 myotubes dose dependently. Nlrp3 knockdown or Nlrp3-/- mice were protected from the imbalance of protein synthesis and degradation. Exposure of C2C12 to Ang II increased mitochondrial ROS (mtROS) generation, accompanied by MtD. Remarkably, the mitochondrial-targeted antioxidant not only decreased mtROS and MtD, it also significantly inhibited NLRP3 inflammasome activation and restored skeletal muscle atrophy. Finally, the PPAR-γ agonist protected against Ang II-induced muscle wasting by preventing MtD, oxidative stress, and NLRP3 inflammasome activation in vitro and in vivo. This work suggests a potential role of MtD/NLRP3 inflammasome pathway in the pathogenesis of Ang II-induced skeletal muscle wasting, and targeting the PPAR-γ/MtD/NLRP3 inflammasome axis may provide a therapeutic approach for muscle wasting.
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Affiliation(s)
- Yuqing Liu
- Division of Nephrology, Shanghai Ninth People's Hospital, School of Medicine, Shanghai Jiaotong University, 639 zhizaoju Road, 200011, Shanghai, China
| | - Xiao Bi
- Division of Nephrology, Shanghai Ninth People's Hospital, School of Medicine, Shanghai Jiaotong University, 639 zhizaoju Road, 200011, Shanghai, China
| | - Yumei Zhang
- Division of Nephrology, Shanghai Ninth People's Hospital, School of Medicine, Shanghai Jiaotong University, 639 zhizaoju Road, 200011, Shanghai, China
| | - Yingdeng Wang
- Division of Nephrology, Shanghai Ninth People's Hospital, School of Medicine, Shanghai Jiaotong University, 639 zhizaoju Road, 200011, Shanghai, China
| | - Wei Ding
- Division of Nephrology, Shanghai Ninth People's Hospital, School of Medicine, Shanghai Jiaotong University, 639 zhizaoju Road, 200011, Shanghai, China.
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8
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Winslow MA, Hall SE. Muscle wasting: A review of exercise, classical and non-classical RAS axes. J Cell Mol Med 2019; 23:5836-5845. [PMID: 31273946 PMCID: PMC6714228 DOI: 10.1111/jcmm.14412] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Revised: 04/27/2019] [Accepted: 05/01/2019] [Indexed: 02/06/2023] Open
Abstract
This review identifies how the classical/non‐classical renin‐angiotensin system (RAS) and exercise influence muscle wasting. The classical RAS axis enhances muscle loss through the interaction with NADPH oxidase (NOX), ubiquitin proteasome system (UPS), protein synthesis and fibrosis pathways. The mainstream hypothesis identifies reactive oxygen species (ROS) as the key pathway in muscle, this review recognizes alternative pathways that lead to an increase in muscle wasting through the classical RAS axis. In addition, pathways in which the non‐classical RAS axis and exercise inhibit the classical RAS axis are also explored. The non‐classical RAS axis and exercise have a significant negative impact on ROS production and protein synthesis. The non‐classical RAS axis has been identified in this review to directly affect protein synthesis pathways not by altering the pre‐existing intracellular ROS level, further supporting the idea that muscle wasting caused by the classical RAS system is not entirely due to ROS production. Exercise has been identified to modify the RAS axes making it a therapeutic option.
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Affiliation(s)
- Mark A Winslow
- Department of Kinesiology, Boise State University, Boise, Idaho
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9
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Forrester SJ, Booz GW, Sigmund CD, Coffman TM, Kawai T, Rizzo V, Scalia R, Eguchi S. Angiotensin II Signal Transduction: An Update on Mechanisms of Physiology and Pathophysiology. Physiol Rev 2018; 98:1627-1738. [PMID: 29873596 DOI: 10.1152/physrev.00038.2017] [Citation(s) in RCA: 634] [Impact Index Per Article: 105.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The renin-angiotensin-aldosterone system plays crucial roles in cardiovascular physiology and pathophysiology. However, many of the signaling mechanisms have been unclear. The angiotensin II (ANG II) type 1 receptor (AT1R) is believed to mediate most functions of ANG II in the system. AT1R utilizes various signal transduction cascades causing hypertension, cardiovascular remodeling, and end organ damage. Moreover, functional cross-talk between AT1R signaling pathways and other signaling pathways have been recognized. Accumulating evidence reveals the complexity of ANG II signal transduction in pathophysiology of the vasculature, heart, kidney, and brain, as well as several pathophysiological features, including inflammation, metabolic dysfunction, and aging. In this review, we provide a comprehensive update of the ANG II receptor signaling events and their functional significances for potential translation into therapeutic strategies. AT1R remains central to the system in mediating physiological and pathophysiological functions of ANG II, and participation of specific signaling pathways becomes much clearer. There are still certain limitations and many controversies, and several noteworthy new concepts require further support. However, it is expected that rigorous translational research of the ANG II signaling pathways including those in large animals and humans will contribute to establishing effective new therapies against various diseases.
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Affiliation(s)
- Steven J Forrester
- Cardiovascular Research Center, Lewis Katz School of Medicine at Temple University , Philadelphia, Pennsylvania ; Department of Pharmacology and Toxicology, School of Medicine, University of Mississippi Medical Center , Jackson, Mississippi ; Department of Pharmacology, Center for Hypertension Research, Roy J. and Lucille A. Carver College of Medicine, University of Iowa , Iowa City, Iowa ; and Duke-NUS, Singapore and Department of Medicine, Duke University Medical Center , Durham, North Carolina
| | - George W Booz
- Cardiovascular Research Center, Lewis Katz School of Medicine at Temple University , Philadelphia, Pennsylvania ; Department of Pharmacology and Toxicology, School of Medicine, University of Mississippi Medical Center , Jackson, Mississippi ; Department of Pharmacology, Center for Hypertension Research, Roy J. and Lucille A. Carver College of Medicine, University of Iowa , Iowa City, Iowa ; and Duke-NUS, Singapore and Department of Medicine, Duke University Medical Center , Durham, North Carolina
| | - Curt D Sigmund
- Cardiovascular Research Center, Lewis Katz School of Medicine at Temple University , Philadelphia, Pennsylvania ; Department of Pharmacology and Toxicology, School of Medicine, University of Mississippi Medical Center , Jackson, Mississippi ; Department of Pharmacology, Center for Hypertension Research, Roy J. and Lucille A. Carver College of Medicine, University of Iowa , Iowa City, Iowa ; and Duke-NUS, Singapore and Department of Medicine, Duke University Medical Center , Durham, North Carolina
| | - Thomas M Coffman
- Cardiovascular Research Center, Lewis Katz School of Medicine at Temple University , Philadelphia, Pennsylvania ; Department of Pharmacology and Toxicology, School of Medicine, University of Mississippi Medical Center , Jackson, Mississippi ; Department of Pharmacology, Center for Hypertension Research, Roy J. and Lucille A. Carver College of Medicine, University of Iowa , Iowa City, Iowa ; and Duke-NUS, Singapore and Department of Medicine, Duke University Medical Center , Durham, North Carolina
| | - Tatsuo Kawai
- Cardiovascular Research Center, Lewis Katz School of Medicine at Temple University , Philadelphia, Pennsylvania ; Department of Pharmacology and Toxicology, School of Medicine, University of Mississippi Medical Center , Jackson, Mississippi ; Department of Pharmacology, Center for Hypertension Research, Roy J. and Lucille A. Carver College of Medicine, University of Iowa , Iowa City, Iowa ; and Duke-NUS, Singapore and Department of Medicine, Duke University Medical Center , Durham, North Carolina
| | - Victor Rizzo
- Cardiovascular Research Center, Lewis Katz School of Medicine at Temple University , Philadelphia, Pennsylvania ; Department of Pharmacology and Toxicology, School of Medicine, University of Mississippi Medical Center , Jackson, Mississippi ; Department of Pharmacology, Center for Hypertension Research, Roy J. and Lucille A. Carver College of Medicine, University of Iowa , Iowa City, Iowa ; and Duke-NUS, Singapore and Department of Medicine, Duke University Medical Center , Durham, North Carolina
| | - Rosario Scalia
- Cardiovascular Research Center, Lewis Katz School of Medicine at Temple University , Philadelphia, Pennsylvania ; Department of Pharmacology and Toxicology, School of Medicine, University of Mississippi Medical Center , Jackson, Mississippi ; Department of Pharmacology, Center for Hypertension Research, Roy J. and Lucille A. Carver College of Medicine, University of Iowa , Iowa City, Iowa ; and Duke-NUS, Singapore and Department of Medicine, Duke University Medical Center , Durham, North Carolina
| | - Satoru Eguchi
- Cardiovascular Research Center, Lewis Katz School of Medicine at Temple University , Philadelphia, Pennsylvania ; Department of Pharmacology and Toxicology, School of Medicine, University of Mississippi Medical Center , Jackson, Mississippi ; Department of Pharmacology, Center for Hypertension Research, Roy J. and Lucille A. Carver College of Medicine, University of Iowa , Iowa City, Iowa ; and Duke-NUS, Singapore and Department of Medicine, Duke University Medical Center , Durham, North Carolina
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10
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Modulation of the renin-angiotensin system in white adipose tissue and skeletal muscle: focus on exercise training. Clin Sci (Lond) 2018; 132:1487-1507. [PMID: 30037837 DOI: 10.1042/cs20180276] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2018] [Revised: 06/13/2018] [Accepted: 06/27/2018] [Indexed: 12/11/2022]
Abstract
Overactivation of the renin-angiotensin (Ang) system (RAS) increases the classical arm (Ang-converting enzyme (ACE)/Ang II/Ang type 1 receptor (AT1R)) to the detriment of the protective arm (ACE2/Ang 1-7/Mas receptor (MasR)). The components of the RAS are present locally in white adipose tissue (WAT) and skeletal muscle, which act co-operatively, through specific mediators, in response to pathophysiological changes. In WAT, up-regulation of the classical arm promotes lipogenesis and reduces lipolysis and adipogenesis, leading to adipocyte hypertrophy and lipid storage, which are related to insulin resistance and increased inflammation. In skeletal muscle, the classical arm promotes protein degradation and increases the inflammatory status and oxidative stress, leading to muscle wasting. Conversely, the protective arm plays a counter-regulatory role by opposing the effect of Ang II. The accumulation of adipose tissue and muscle mass loss is associated with a higher risk of morbidity and mortality, which could be related, in part, to overactivation of the RAS. On the other hand, exercise training (ExT) shifts the balance of the RAS towards the protective arm, promoting the inhibition of the classical arm in parallel with the stimulation of the protective arm. Thus, fat mobilization and maintenance of muscle mass and function are facilitated. However, the mechanisms underlying exercise-induced changes in the RAS remain unclear. In this review, we present the RAS as a key mechanism of WAT and skeletal muscle metabolic dysfunction. Furthermore, we discuss the interaction between the RAS and exercise and the possible underlying mechanisms of the health-related aspects of ExT.
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Development of obesity can be prevented in rats by chronic icv infusions of AngII but less by Ang(1-7). Pflugers Arch 2018; 470:867-881. [PMID: 29430615 DOI: 10.1007/s00424-018-2117-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Revised: 01/30/2018] [Accepted: 02/01/2018] [Indexed: 02/07/2023]
Abstract
Considering that obesity is one of the leading risks for death worldwide, it should be noted that a brain-related mechanism is involved in AngII-induced and AT1-receptor-dependent weight loss. It is moreover established that activation of the Ang(1-7)/ACE2/Mas axis reduces weight, but it remains unclear whether this Ang(1-7) effect is also mediated via a brain-related mechanism. Additionally to Sprague Dawley (SD) rats, we used TGR(ASrAOGEN) selectively lacking brain angiotensinogen, the precursor to AngII, as we speculated that effects are more pronounced in a model with low brain RAS activity. Rats were fed with high-calorie cafeteria diet. We investigated weight regulation, food behavior, and energy balance in response to chronic icv.-infusions of AngII (200 ng•h-1), or Ang(1-7) (200/600 ng•h-1) or artificial cerebrospinal fluid. High- but not low-dose Ang(1-7) slightly decreased weight gain and energy intake in SD rats. AngII showed an anti-obese efficacy in SD rats by decreasing energy intake and increasing energy expenditure and also improved glucose control. TGR(ASrAOGEN) were protected from developing obesity. However, Ang(1-7) did not reveal any effects in TGR(ASrAOGEN) and those of AngII were minor compared to SD rats. Our results emphasize that brain AngII is a key contributor for regulating energy homeostasis and weight in obesity by serving as a negative brain-related feedback signal to alleviate weight gain. Brain-related anti-obese potency of Ang(1-7) is lower than AngII but must be further investigated by using other transgenic models as TGR(ASrAOGEN) proved to be less valuable for answering this question.
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Sfyri P, Matsakas A. Crossroads between peripheral atherosclerosis, western-type diet and skeletal muscle pathophysiology: emphasis on apolipoprotein E deficiency and peripheral arterial disease. J Biomed Sci 2017; 24:42. [PMID: 28688452 PMCID: PMC5502081 DOI: 10.1186/s12929-017-0346-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2017] [Accepted: 06/07/2017] [Indexed: 12/16/2022] Open
Abstract
Atherosclerosis is a chronic inflammatory process that, in the presence of hyperlipidaemia, promotes the formation of atheromatous plaques in large vessels of the cardiovascular system. It also affects peripheral arteries with major implications for a number of other non-vascular tissues such as the skeletal muscle, the liver and the kidney. The aim of this review is to critically discuss and assimilate current knowledge on the impact of peripheral atherosclerosis and its implications on skeletal muscle homeostasis. Accumulating data suggests that manifestations of peripheral atherosclerosis in skeletal muscle originates in a combination of increased i)-oxidative stress, ii)-inflammation, iii)-mitochondrial deficits, iv)-altered myofibre morphology and fibrosis, v)-chronic ischemia followed by impaired oxygen supply, vi)-reduced capillary density, vii)- proteolysis and viii)-apoptosis. These structural, biochemical and pathophysiological alterations impact on skeletal muscle metabolic and physiologic homeostasis and its capacity to generate force, which further affects the individual's quality of life. Particular emphasis is given on two major areas representing basic and applied science respectively: a)-the abundant evidence from a well-recognised atherogenic model; the Apolipoprotein E deficient mouse and the role of a western-type diet and b)-on skeletal myopathy and oxidative stress-induced myofibre damage from human studies on peripheral arterial disease. A significant source of reactive oxygen species production and oxidative stress in cardiovascular disease is the family of NADPH oxidases that contribute to several pathologies. Finally, strategies targeting NADPH oxidases in skeletal muscle in an attempt to attenuate cellular oxidative stress are highlighted, providing a better understanding of the crossroads between peripheral atherosclerosis and skeletal muscle pathophysiology.
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Affiliation(s)
- Peggy Sfyri
- Molecular Physiology Laboratory, Centre for Atherothrombotic & Metabolic Disease, Hull York Medical School, University of Hull, Cottingham Road, Hull, HU6 7RX, United Kingdom
| | - Antonios Matsakas
- Molecular Physiology Laboratory, Centre for Atherothrombotic & Metabolic Disease, Hull York Medical School, University of Hull, Cottingham Road, Hull, HU6 7RX, United Kingdom.
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The nuclear phosphatase SCP4 regulates FoxO transcription factors during muscle wasting in chronic kidney disease. Kidney Int 2017; 92:336-348. [PMID: 28506762 DOI: 10.1016/j.kint.2017.02.031] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Revised: 02/16/2017] [Accepted: 02/23/2017] [Indexed: 12/21/2022]
Abstract
Chronic kidney disease (CKD) and related inflammatory responses stimulate protein-energy wasting, a complication causing loss of muscle mass. Primarily, muscle wasting results from accelerated protein degradation via autophagic/lysosomal and proteasomal pathways, but mechanisms regulating these proteolysis pathways remain unclear. Since dephosphorylation of FoxOs regulates ubiquitin/proteasome protein metabolism, we tested whether a novel nuclear phosphatase, the small C-terminal domain phosphatase (SCP) 4, regulates FoxOs signaling and, in turn, muscle wasting. In cultured mouse myoblast cells, SCP4 overexpression stimulated proteolysis, while knockdown of SCP4 prevented the proteolysis stimulated by inflammatory cytokines. SCP4 overexpression led to nuclear accumulation of FoxO1/3a followed by increased expression of catabolic factors including myostatin, Atrogin-1, and MuRF-1, and induction of lysosomal-mediated proteolysis. Treatment of C2C12 myotubes with proinflammatory cytokines stimulated SCP4 expression in an NF-κB-dependent manner. In skeletal muscle of mice with CKD, SCP4 expression was up-regulated. Similarly, in skeletal muscle of patients with CKD, SCP4 expression was significantly increased. Knockdown of SCP4 significantly suppressed FoxO1/3a-mediated expression of Atrogin-1 and MuRF-1 and prevented muscle wasting in mice with CKD. Thus, SCP4 is a novel regulator of FoxO transcription factors and promotes cellular proteolysis. Hence, targeting SCP4 may prevent muscle wasting in CKD and possibly other catabolic conditions.
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Yoshida T, Delafontaine P. An Intronic Enhancer Element Regulates Angiotensin II Type 2 Receptor Expression during Satellite Cell Differentiation, and Its Activity Is Suppressed in Congestive Heart Failure. J Biol Chem 2016; 291:25578-25590. [PMID: 27756842 DOI: 10.1074/jbc.m116.752501] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2016] [Revised: 10/17/2016] [Indexed: 12/20/2022] Open
Abstract
Patients with advanced congestive heart failure (CHF) or chronic kidney disease often have increased angiotensin II (Ang II) levels and cachexia. We previously demonstrated that Ang II, via its type 1 receptor, causes muscle protein breakdown and apoptosis and inhibits satellite cell (SC) proliferation and muscle regeneration, likely contributing to cachexia in CHF and chronic kidney disease. In contrast, Ang II, via its type 2 receptor (AT2R) expression, is robustly induced during SC differentiation, and it potentiates muscle regeneration. To understand the mechanisms regulating AT2R expression and its potential role in muscle regeneration in chronic diseases, we used a mouse model of CHF and found that muscle regeneration was markedly reduced and that this was accompanied by blunted increase of AT2R expression. We performed AT2R promoter reporter analysis during satellite cell differentiation and found that the 70 bp upstream of the AT2R transcription start site contain a core promoter region, and regions upstream of 70 bp to 3 kbp are dispensable for AT2R induction. Instead, AT2R intron 2 acts as a transcriptional enhancer during SC differentiation. Further deletion/mutation analysis revealed that multiple transcription factor binding sites in the +286/+690 region within intron 2 coordinately regulate AT2R transcription. Importantly, +286/+690 enhancer activity was suppressed in CHF mouse skeletal muscle, suggesting that AT2R expression is suppressed in CHF via inhibition of AT2R intronic enhancer activity, leading to lowered muscle regeneration. Thus targeting intron 2 enhancer element could lead to the development of a novel intervention to increase AT2R expression in SCs and potentiate skeletal muscle regenerative capacity in chronic diseases.
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Affiliation(s)
- Tadashi Yoshida
- From the Department of Medicine and Medical Pharmacology and Physiology, University of Missouri School of Medicine, Columbia, Missouri 65212
| | - Patrice Delafontaine
- From the Department of Medicine and Medical Pharmacology and Physiology, University of Missouri School of Medicine, Columbia, Missouri 65212
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Winkler M, Schuchard J, Stölting I, Vogt FM, Barkhausen J, Thorns C, Bader M, Raasch W. The brain renin-angiotensin system plays a crucial role in regulating body weight in diet-induced obesity in rats. Br J Pharmacol 2016; 173:1602-17. [PMID: 26892671 DOI: 10.1111/bph.13461] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2015] [Revised: 02/04/2016] [Accepted: 02/14/2016] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND AND PURPOSE Reduced weight gain after treatment with AT1 receptor antagonists may involve a brain-related mechanism. Here, we investigated the role of the brain renin-angiotensin system on weight regulation and food behaviour, with or without additional treatment with telmisartan. METHODS Transgenic rats with a brain-specific deficiency in angiotensinogen (TGR(ASrAOGEN)) and the corresponding wild-type, Sprague Dawley (SD) rats were fed (3 months) with a high-calorie cafeteria diet (CD) or standard chow. SD and TGR(ASrAOGEN) rats on the CD diet were also treated with telmisartan (8 mg·kg(-1) ·d(-1) , 3 months). RESULTS Compared with SD rats, TGR(ASrAOGEN) rats (i) had lower weights during chow feeding, (ii) did not become obese during CD feeding, (iii) had normal baseline leptin plasma concentrations independent of the feeding regimen, whereas plasma leptin of SD rats was increased due to CD, (iv) showed a reduced energy intake, (v) had a higher, strain-dependent energy expenditure, which is additionally enhanced during CD feeding, (vi) had enhanced mRNA levels of pro-opiomelanocortin and (vii) showed improved glucose control. Weight gain and energy intake in rats fed the CD diet were markedly reduced by telmisartan in SD rats but only to a minor extent in TGR(ASrAOGEN) rats. CONCLUSIONS The brain renin-angiotensin system affects body weight regulation, feeding behaviour and metabolic disorders. When angiotensin II levels are low in brain, rats are protected from developing diet-induced obesity and obesity-related metabolic impairments. We further suggest that telmisartan at least partly lowers body weight via a CNS-driven mechanism.
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Affiliation(s)
- Martina Winkler
- Institute of Experimental and Clinical Pharmacology and Toxicology, University of Lübeck, Lübeck, Germany
| | - Johanna Schuchard
- Institute of Experimental and Clinical Pharmacology and Toxicology, University of Lübeck, Lübeck, Germany.,DZHK (German Centre for Cardiovascular Research), partner site Hamburg/Kiel/Lübeck, Lübeck, Germany
| | - Ines Stölting
- Institute of Experimental and Clinical Pharmacology and Toxicology, University of Lübeck, Lübeck, Germany
| | - Florian M Vogt
- Department for Radiology and Nuclear Medicine, University of Lübeck, Lübeck, Germany
| | - Jörg Barkhausen
- Department for Radiology and Nuclear Medicine, University of Lübeck, Lübeck, Germany
| | - Christoph Thorns
- Department of Pathology, University Clinic Schleswig-Holstein, Campus Lübeck, Lübeck, Germany
| | - Michael Bader
- Max-Delbrück-Center for Molecular Medicine (MDC), Berlin, Germany.,DZHK (German Centre for Cardiovascular Research), partner site Berlin, Berlin, Germany.,Center for Structural and Cell Biology in Medicine, Institute for Biology, University of Lübeck, Lübeck, Germany.,Charité - University Medicine Berlin, Berlin, Germany
| | - Walter Raasch
- Institute of Experimental and Clinical Pharmacology and Toxicology, University of Lübeck, Lübeck, Germany.,DZHK (German Centre for Cardiovascular Research), partner site Hamburg/Kiel/Lübeck, Lübeck, Germany.,CBBM (Center of Brain, Behavior and Metabolism), Lübeck, Germany
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DELAFONTAINE PATRICE, YOSHIDA TADASHI. THE RENIN-ANGIOTENSIN SYSTEM AND THE BIOLOGY OF SKELETAL MUSCLE: MECHANISMS OF MUSCLE WASTING IN CHRONIC DISEASE STATES. TRANSACTIONS OF THE AMERICAN CLINICAL AND CLIMATOLOGICAL ASSOCIATION 2016; 127:245-258. [PMID: 28066057 PMCID: PMC5216488] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Sarcopenia and cachexia are muscle-wasting syndromes associated with aging and with many chronic diseases such as congestive heart failure, diabetes, cancer, chronic obstructive pulmonary disease, and renal failure. While mechanisms are complex, these conditions are often accompanied by elevated angiotensin II (Ang II). We found that Ang II infusion in rodents leads to skeletal muscle wasting via alterations in insulin-like growth factor-1 signaling, increased apoptosis, enhanced muscle protein breakdown via the ubiquitin-proteasome system, and decreased appetite resulting from downregulation of hypothalamic orexigenic neuropeptides orexin and neuropeptide Y. Furthermore, Ang II inhibits skeletal muscle stem cell proliferation, leading to lowered muscle regenerative capacity. Distinct stem cell Ang II receptor subtypes are critical for regulation of muscle regeneration. In ischemic mouse congestive heart failure model skeletal muscle wasting and attenuated muscle regeneration are Ang II dependent. These data suggest that the renin-angiotensin system plays a critical role in mechanisms underlying cachexia in chronic disease states.
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Affiliation(s)
- PATRICE DELAFONTAINE
- Correspondence and reprint requests: Patrice Delafontaine, MD,
Department of Medicine and Medical Pharmacology and Physiology, University of Missouri School of Medicine, One Hospital Drive, CE323, Columbia, Missouri 65212573-884-9260573-884-4808
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Abstract
Sarcopenia and cachexia are muscle wasting syndromes associated with aging and with many chronic diseases, such as congestive heart failure (CHF), diabetes, cancer, chronic obstructive pulmonary disease and chronic kidney disease (CKD). While mechanisms are complex, these conditions are often accompanied by elevated angiotensin II (Ang II). Patients with advanced CHF or CKD often have increased Ang II levels and cachexia, and angiotensin-converting enzyme inhibitor treatment improves weight loss. It was found that Ang II infusion in rodents leads to skeletal muscle wasting. Ang II increases cytokines and circulating hormones, such as tumor necrosis factor-α, interleukin-6, serum amyloid-A and glucocorticoids, which regulate muscle protein synthesis and degradation. Ang II-induced muscle wasting is caused by alterations in insulin-like growth factor-1 signaling, enhanced muscle protein breakdown via the ubiquitin-proteasome system and decreased appetite resulting from the downregulation of hypothalamic orexigenic neuropeptides, such as Npy and orexin. Ang II also inhibits 5' adenosine monophosphate-activated protein kinase activity and disrupts normal energy balance via the activation of 5' adenosine monophosphate-activated protein kinase phosphatase PP2Cα. Furthermore, Ang II inhibits skeletal muscle stem (satellite) cell proliferation, leading to lowered muscle regenerative capacity. Distinct satellite cell angiotensin receptor subtypes have different effects on different stages of differentiation and are critical for the regulation of muscle regeneration. These data suggest that the renin-angiotensin system plays a critical role in mechanisms underlying cachexia in chronic disease states, and it is a promising target for the treatment of muscle atrophy in patients with diseases such as CHF and CKD.
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Affiliation(s)
- Tadashi Yoshida
- Department of Medicine, University of Missouri-Columbia, Columbia, MO
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18
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Schuchard J, Winkler M, Stölting I, Schuster F, Vogt FM, Barkhausen J, Thorns C, Santos RA, Bader M, Raasch W. Lack of weight gain after angiotensin AT1 receptor blockade in diet-induced obesity is partly mediated by an angiotensin-(1-7)/Mas-dependent pathway. Br J Pharmacol 2015; 172:3764-78. [PMID: 25906670 DOI: 10.1111/bph.13172] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Revised: 03/24/2015] [Accepted: 04/04/2015] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND AND PURPOSE Angiotensin AT1 receptor antagonists induce weight loss; however, the mechanism underlying this phenomenon is unknown. The Mas receptor agonist angiotensin-(1-7) is a metabolite of angiotensin I and of angiotensin II . As an agonist of Mas receptors, angiotensin-(1-7) has beneficial cardiovascular and metabolic effects. EXPERIMENTAL APPROACH We investigated the anti-obesity effects of transgenically overexpressed angiotensin-(1-7) in rats. We secondly examined whether weight loss due to telmisartan (8 mg·kg(-1) ·d(-1) ) in diet-induced obese Sprague Dawley (SD) rats can be blocked when the animals were co-treated with the Mas receptor antagonist A779 (24 or 72 μg·kg(-1) ·d(-1) ). KEY RESULTS In contrast to wild-type controls, transgenic rats overexpressing angiotensin-(1-7) had 1.) diminished body weight when they were regularly fed with chow; 2.) were protected from developing obesity although they were fed with cafeteria diet (CD); 3.) showed a reduced energy intake that was mainly related to a lower CD intake; 5.) remained responsive to leptin despite chronic CD feeding; 6.) had a higher, strain-dependent energy expenditure, and 7.) were protected from developing insulin resistance despite CD feeding. Telmisartan-induced weight loss in SD rats was partially antagonized after a high, but not a low dose of A779. CONCLUSIONS AND IMPLICATIONS Angiotensin-(1-7) regulated food intake and body weight and contributed to the weight loss after AT1 receptor blockade. Angiotensin-(1-7)-like agonists may be drug candidates for treating obesity.
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Affiliation(s)
- Johanna Schuchard
- Institute of Experimental and Clinical Pharmacology and Toxicology, University of Lübeck, Lübeck, Germany.,DZHK (German Centre for Cardiovascular Research), Partner Site Hamburg/Kiel/Lübeck, Lübeck, Germany
| | - Martina Winkler
- Institute of Experimental and Clinical Pharmacology and Toxicology, University of Lübeck, Lübeck, Germany
| | - Ines Stölting
- Institute of Experimental and Clinical Pharmacology and Toxicology, University of Lübeck, Lübeck, Germany
| | - Franziska Schuster
- Institute of Experimental and Clinical Pharmacology and Toxicology, University of Lübeck, Lübeck, Germany
| | - Florian M Vogt
- Department for Radiology and Nuclear Medicine, University of Lübeck, Lübeck, Germany
| | - Jörg Barkhausen
- Department for Radiology and Nuclear Medicine, University of Lübeck, Lübeck, Germany
| | - Christoph Thorns
- Department of Pathology, University Clinic Schleswig-Holstein, Luebeck, Germany
| | - Robson A Santos
- National Institute of Science and Technology in Nanobiopharmaceutics, Department of Physiology and Biophysics, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Michael Bader
- National Institute of Science and Technology in Nanobiopharmaceutics, Department of Physiology and Biophysics, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.,Max-Delbrück-Center for Molecular Medicine (MDC), Berlin, Germany.,DZHK (German Centre for Cardiovascular Research), Partner Site Berlin, Berlin, Germany.,Center for Structural and Cell Biology in Medicine, Institute for Biology, University of Lübeck, Lübeck, Germany.,Charité - University Medicine Berlin, Berlin, Germany
| | - Walter Raasch
- Institute of Experimental and Clinical Pharmacology and Toxicology, University of Lübeck, Lübeck, Germany.,DZHK (German Centre for Cardiovascular Research), Partner Site Hamburg/Kiel/Lübeck, Lübeck, Germany
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Affiliation(s)
- Didier Attaix
- aClermont Université, Université d'Auvergne, Unité de Nutrition Humaine bINRA, UMR 1019, UNH, CRNH Auvergne, Clermont-Ferrand, France cNutrition Unit, Geneva University Hospital, Geneva, Switzerland dDepartment of Oncology, University of Alberta, Edmonton, Alberta, Canada
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