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Kalupahana NS, Moustaid-Moussa N. Beyond blood pressure, fluid and electrolyte homeostasis - Role of the renin angiotensin aldosterone system in the interplay between metabolic diseases and breast cancer. Acta Physiol (Oxf) 2024; 240:e14164. [PMID: 38770946 DOI: 10.1111/apha.14164] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2024] [Revised: 04/16/2024] [Accepted: 04/29/2024] [Indexed: 05/22/2024]
Abstract
The classical renin angiotensin aldosterone system (RAAS), as well as the recently described counter-regulatory or non-canonical RAAS have been well characterized for their role in cardiovascular homeostasis. Moreover, extensive research has been conducted over the past decades on both paracrine and the endocrine roles of local RAAS in various metabolic regulations and in chronic diseases. Clinical evidence from patients on RAAS blockers as well as pre-clinical studies using rodent models of genetic manipulations of RAAS genes documented that this system may play important roles in the interplay between metabolic diseases and cancer, namely breast cancer. Some of these studies suggest potential therapeutic applications and repurposing of RAAS inhibitors for these diseases. In this review, we discuss the mechanisms by which RAAS is involved in the pathogenesis of metabolic diseases such as obesity and type-2 diabetes as well as the role of this system in the initiation, expansion and/or progression of breast cancer, especially in the context of metabolic diseases.
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Affiliation(s)
- Nishan Sudheera Kalupahana
- Department of Nutrition and Health, College of Medicine and Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates
| | - Naima Moustaid-Moussa
- Department of Nutritional Sciences and Obesity Research Institute, Texas Tech University, Lubbock, Texas, USA
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2
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Vrachnis D, Fotiou A, Mantzou A, Pergialiotis V, Antsaklis P, Valsamakis G, Stavros S, Machairiotis N, Iavazzo C, Kanaka-Gantenbein C, Mastorakos G, Drakakis P, Vrachnis N, Antonakopoulos N. Second Trimester Amniotic Fluid Angiotensinogen Levels Linked to Increased Fetal Birth Weight and Shorter Gestational Age in Term Pregnancies. Life (Basel) 2024; 14:206. [PMID: 38398716 PMCID: PMC10890398 DOI: 10.3390/life14020206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2023] [Revised: 01/26/2024] [Accepted: 01/30/2024] [Indexed: 02/25/2024] Open
Abstract
BACKGROUND Despite the considerable progress made in recent years in fetal assessment, the etiology of fetal growth disturbances is not as yet well understood. In an effort to enhance our knowledge in this area, we investigated the associations of the amniotic fluid angiotensinogen of the renin-angiotensin system with fetal growth abnormalities. METHODS We collected amniotic fluid samples from 70 pregnant women who underwent amniocentesis during their early second trimester. Birth weight was documented upon delivery, after which the embryos corresponding to the respective amniotic fluid samples were categorized into three groups as follows: small for gestational age (SGA), appropriate for gestational age (AGA), and large for gestational age (LGA). Amniotic fluid angiotensinogen levels were determined by using ELISA kits. RESULTS Mean angiotensinogen values were 3885 ng/mL (range: 1625-5375 ng/mL), 4885 ng/mL (range: 1580-8460 ng/mL), and 4670 ng/mL (range: 1995-7250 ng/mL) in the SGA, LGA, and AGA fetuses, respectively. The concentrations in the three groups were not statistically significantly different. Although there were wide discrepancies between the mean values of the subgroups, the large confidence intervals in the three groups negatively affected the statistical analysis. However, multiple regression analysis revealed a statistically significant negative correlation between the angiotensinogen levels and gestational age and a statistically significant positive correlation between the birth weight and angiotensinogen levels. DISCUSSION Our findings suggest that fetal growth abnormalities did not correlate with differences in the amniotic fluid levels of angiotensinogen in early second trimester pregnancies. However, increased angiotensinogen levels were found to be consistent with a smaller gestational age at birth and increased BMI of neonates.
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Affiliation(s)
- Dionysios Vrachnis
- National and Kapodistrian University of Athens Medical School, 11527 Athens, Greece; (D.V.); (A.F.)
| | - Alexandros Fotiou
- National and Kapodistrian University of Athens Medical School, 11527 Athens, Greece; (D.V.); (A.F.)
| | - Aimilia Mantzou
- Aghia Sophia Children’s Hospital, National and Kapodistrian University of Athens, 11527 Athens, Greece; (A.M.); (C.K.-G.)
| | - Vasilios Pergialiotis
- First Department of Obstetrics and Gynecology, National and Kapodistrian University of Athens Medical School, Alexandra Hospital, 11527 Athens, Greece; (V.P.); (P.A.)
| | - Panagiotis Antsaklis
- First Department of Obstetrics and Gynecology, National and Kapodistrian University of Athens Medical School, Alexandra Hospital, 11527 Athens, Greece; (V.P.); (P.A.)
| | - George Valsamakis
- Second Department of Obstetrics and Gynecology, National and Kapodistrian University of Athens Medical School, Aretaieion Hospital, 11527 Athens, Greece;
| | - Sofoklis Stavros
- Third Department of Obstetrics and Gynecology, National and Kapodistrian University of Athens Medical School, Attikon Hospital, 11527 Athens, Greece; (S.S.); (N.M.); (P.D.)
| | - Nikolaos Machairiotis
- Third Department of Obstetrics and Gynecology, National and Kapodistrian University of Athens Medical School, Attikon Hospital, 11527 Athens, Greece; (S.S.); (N.M.); (P.D.)
| | - Christos Iavazzo
- Department of Gynecologic Oncology, Metaxa Memorial Cancer Hospital of Piraeus, 18537 Piraeus, Greece;
| | - Christina Kanaka-Gantenbein
- Aghia Sophia Children’s Hospital, National and Kapodistrian University of Athens, 11527 Athens, Greece; (A.M.); (C.K.-G.)
| | - George Mastorakos
- Unit of Endocrinology, Diabetes Mellitus and Metabolism, National and Kapodistrian University of Athens Medical School, Aretaieion Hospital, 11527 Athens, Greece;
| | - Petros Drakakis
- Third Department of Obstetrics and Gynecology, National and Kapodistrian University of Athens Medical School, Attikon Hospital, 11527 Athens, Greece; (S.S.); (N.M.); (P.D.)
| | - Nikolaos Vrachnis
- Third Department of Obstetrics and Gynecology, National and Kapodistrian University of Athens Medical School, Attikon Hospital, 11527 Athens, Greece; (S.S.); (N.M.); (P.D.)
- Vascular Biology, Molecular and Clinical Sciences Research Institute, St George’s University of London, London SW17 0RE, UK
| | - Nikolaos Antonakopoulos
- Department of Obstetrics and Gynecology, University Hospital of Patras, Medical School, University of Patras, 26504 Patra, Greece
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Rocha HNM, Teixeira GF, Batista GMS, Storch AS, Garcia VP, Mentzinger J, Gomes EAC, Campos MO, Nóbrega ACL, Rocha NG. AT1R blocker prevents mental stress induced retrograde blood flow in overweight/obese men. Physiol Rep 2023; 11:e15566. [PMID: 36636769 PMCID: PMC9837474 DOI: 10.14814/phy2.15566] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Revised: 12/21/2022] [Accepted: 12/23/2022] [Indexed: 06/17/2023] Open
Abstract
The main goal was to determine the impact of mental stress (MS) on blood flow regulation in overweight/obese men. Fourteen overweight/obese men (27 ± 7 years; 29.8 ± 2.6 kg/m2 ) participated in two randomized experimental sessions with oral administration of the AT1R blocker Olmesartan (40 mg; AT1RB) or placebo (PL). After 2 h, a 5-min acute MS session (Stroop Color Word Test) was administered. Blood flow was assessed at baseline and during the first 3 min of MS by vascular ultrasound in the brachial artery. Blood was collected before (baseline) and during mental stress (MS) for measurement of nitrite (chemiluminescence) and endothelin-1 (ELISA kit). The AT1R blocker was able to reverse the MS responses observed in the placebo session for retrograde flow (p < 0.01), retrograde SR (p < 0.01) and oscillatory shear index (p = 0.01). Regarding vasoactive substances, no differences were observed in ET-1 (p > 0.05) responses to MS between experimental sessions. However, for nitrite responses, the administration of the AT1R blocker was able to increase circulating levels of NO (p = 0.03) Blockade of AT1R appears to prevent the decrease in endothelial function by reducing low shear stress and maintaining the vasoactive substances balance after MS in overweight/obese men.
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Affiliation(s)
- Helena N. M. Rocha
- Department of Physiology and Pharmacology, Laboratory of Exercise SciencesFluminense Federal UniversityNiteroiBrazil
- Department of Physiology and Pharmacology, Laboratory of Integrative CardiometabologyFluminense Federal UniversityNiteroiBrazil
- National Institute of Science and Technology (INCT) ‐ Physical (In)activity and Exercise, National Council for Scientific and Technological Development (CNPq), Fluminense Federal UniversityNiteroiBrazil
| | - Gabriel F. Teixeira
- Department of Physiology and Pharmacology, Laboratory of Exercise SciencesFluminense Federal UniversityNiteroiBrazil
- Department of Physiology and Pharmacology, Laboratory of Integrative CardiometabologyFluminense Federal UniversityNiteroiBrazil
| | - Gabriel M. S. Batista
- Department of Physiology and Pharmacology, Laboratory of Exercise SciencesFluminense Federal UniversityNiteroiBrazil
- Department of Physiology and Pharmacology, Laboratory of Integrative CardiometabologyFluminense Federal UniversityNiteroiBrazil
- National Institute of Science and Technology (INCT) ‐ Physical (In)activity and Exercise, National Council for Scientific and Technological Development (CNPq), Fluminense Federal UniversityNiteroiBrazil
| | - Amanda S. Storch
- Department of Physiology and Pharmacology, Laboratory of Exercise SciencesFluminense Federal UniversityNiteroiBrazil
- Department of Physiology and Pharmacology, Laboratory of Integrative CardiometabologyFluminense Federal UniversityNiteroiBrazil
- National Institute of Science and Technology (INCT) ‐ Physical (In)activity and Exercise, National Council for Scientific and Technological Development (CNPq), Fluminense Federal UniversityNiteroiBrazil
| | - Vinicius P. Garcia
- Department of Physiology and Pharmacology, Laboratory of Exercise SciencesFluminense Federal UniversityNiteroiBrazil
- Department of Physiology and Pharmacology, Laboratory of Integrative CardiometabologyFluminense Federal UniversityNiteroiBrazil
- National Institute of Science and Technology (INCT) ‐ Physical (In)activity and Exercise, National Council for Scientific and Technological Development (CNPq), Fluminense Federal UniversityNiteroiBrazil
| | - Juliana Mentzinger
- Department of Physiology and Pharmacology, Laboratory of Exercise SciencesFluminense Federal UniversityNiteroiBrazil
- Department of Physiology and Pharmacology, Laboratory of Integrative CardiometabologyFluminense Federal UniversityNiteroiBrazil
| | - Erika A. C. Gomes
- Department of Physiology and Pharmacology, Laboratory of Exercise SciencesFluminense Federal UniversityNiteroiBrazil
- National Institute of Science and Technology (INCT) ‐ Physical (In)activity and Exercise, National Council for Scientific and Technological Development (CNPq), Fluminense Federal UniversityNiteroiBrazil
| | - Monique O. Campos
- Department of Physiology and Pharmacology, Laboratory of Exercise SciencesFluminense Federal UniversityNiteroiBrazil
- National Institute of Science and Technology (INCT) ‐ Physical (In)activity and Exercise, National Council for Scientific and Technological Development (CNPq), Fluminense Federal UniversityNiteroiBrazil
| | - Antonio C. L. Nóbrega
- Department of Physiology and Pharmacology, Laboratory of Exercise SciencesFluminense Federal UniversityNiteroiBrazil
- National Institute of Science and Technology (INCT) ‐ Physical (In)activity and Exercise, National Council for Scientific and Technological Development (CNPq), Fluminense Federal UniversityNiteroiBrazil
| | - Natália G. Rocha
- Department of Physiology and Pharmacology, Laboratory of Exercise SciencesFluminense Federal UniversityNiteroiBrazil
- Department of Physiology and Pharmacology, Laboratory of Integrative CardiometabologyFluminense Federal UniversityNiteroiBrazil
- National Institute of Science and Technology (INCT) ‐ Physical (In)activity and Exercise, National Council for Scientific and Technological Development (CNPq), Fluminense Federal UniversityNiteroiBrazil
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Kahlon T, Carlisle S, Otero Mostacero D, Williams N, Trainor P, DeFilippis AP. Angiotensinogen: More Than its Downstream Products: Evidence From Population Studies and Novel Therapeutics. JACC. HEART FAILURE 2022; 10:699-713. [PMID: 35963818 DOI: 10.1016/j.jchf.2022.06.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Revised: 06/08/2022] [Accepted: 06/08/2022] [Indexed: 06/15/2023]
Abstract
The renin-angiotensin-aldosterone system (RAAS) is a well-defined pathway playing a key role in maintaining circulatory homeostasis. Abnormal activation of RAAS contributes to development of cardiovascular disease, including heart failure, cardiac hypertrophy, hypertension, and atherosclerosis. Although several key RAAS enzymes and peptide hormones have been thoroughly investigated, the role of angiotensinogen-the precursor substrate of the RAAS pathway-remains less understood. The study of angiotensinogen single-nucleotide polymorphisms (SNPs) has provided insight into associations between angiotensinogen and hypertension, congestive heart failure, and atherosclerotic cardiovascular disease. Targeted drug therapy of RAAS has dramatically improved clinical outcomes for patients with heart failure, myocardial infarction, and hypertension. However, all such therapeutics block RAAS components downstream of angiotensinogen and elicit compensatory pathways that limit their therapeutic efficacy as monotherapy. Upstream RAAS targeting by an angiotensinogen inhibitor has the potential to be more efficacious in patients with suboptimal RAAS inhibition and has a better safety profile than multiagent RAAS blockade. Newly developed therapeutics that target angiotensinogen through antisense oligonucleotides or silencer RNA technologies are providing a novel perspective into the pathobiology of angiotensinogen and show promise as the next frontier in the treatment of cardiovascular disease.
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Affiliation(s)
- Tanvir Kahlon
- Division of Cardiovascular Medicine, University of Louisville, Louisville, Kentucky, USA
| | - Samantha Carlisle
- Department of Chemistry and Biochemistry, New Mexico State University, Las Cruces, New Mexico, USA
| | - Diana Otero Mostacero
- Division of Cardiovascular Medicine, University of Louisville, Louisville, Kentucky, USA
| | - Nina Williams
- Warren Clinic Cardiology of Tulsa, St Francis Hospital, Tulsa, Oklahoma, USA
| | - Patrick Trainor
- Department of Chemistry and Biochemistry, New Mexico State University, Las Cruces, New Mexico, USA
| | - Andrew P DeFilippis
- Division of Cardiovascular Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, USA.
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Moraes DS, Lelis DDF, Andrade JMO, Meyer L, Guimarães ALS, De Paula AMB, Farias LC, Santos SHS. Enalapril improves obesity associated liver injury ameliorating systemic metabolic markers by modulating Angiotensin Converting Enzymes ACE/ACE2 expression in high-fat feed mice. Prostaglandins Other Lipid Mediat 2021; 152:106501. [DOI: 10.1016/j.prostaglandins.2020.106501] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2020] [Revised: 09/24/2020] [Accepted: 10/05/2020] [Indexed: 02/07/2023]
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Hammoud SH, AlZaim I, Al-Dhaheri Y, Eid AH, El-Yazbi AF. Perirenal Adipose Tissue Inflammation: Novel Insights Linking Metabolic Dysfunction to Renal Diseases. Front Endocrinol (Lausanne) 2021; 12:707126. [PMID: 34408726 PMCID: PMC8366229 DOI: 10.3389/fendo.2021.707126] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/09/2021] [Accepted: 07/19/2021] [Indexed: 12/15/2022] Open
Abstract
A healthy adipose tissue (AT) is indispensable to human wellbeing. Among other roles, it contributes to energy homeostasis and provides insulation for internal organs. Adipocytes were previously thought to be a passive store of excess calories, however this view evolved to include an endocrine role. Adipose tissue was shown to synthesize and secrete adipokines that are pertinent to glucose and lipid homeostasis, as well as inflammation. Importantly, the obesity-induced adipose tissue expansion stimulates a plethora of signals capable of triggering an inflammatory response. These inflammatory manifestations of obese AT have been linked to insulin resistance, metabolic syndrome, and type 2 diabetes, and proposed to evoke obesity-induced comorbidities including cardiovascular diseases (CVDs). A growing body of evidence suggests that metabolic disorders, characterized by AT inflammation and accumulation around organs may eventually induce organ dysfunction through a direct local mechanism. Interestingly, perirenal adipose tissue (PRAT), surrounding the kidney, influences renal function and metabolism. In this regard, PRAT emerged as an independent risk factor for chronic kidney disease (CKD) and is even correlated with CVD. Here, we review the available evidence on the impact of PRAT alteration in different metabolic states on the renal and cardiovascular function. We present a broad overview of novel insights linking cardiovascular derangements and CKD with a focus on metabolic disorders affecting PRAT. We also argue that the confluence among these pathways may open several perspectives for future pharmacological therapies against CKD and CVD possibly by modulating PRAT immunometabolism.
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Affiliation(s)
- Safaa H. Hammoud
- Department of Pharmacology and Therapeutics, Faculty of Pharmacy, Beirut Arab University, Beirut, Lebanon
| | - Ibrahim AlZaim
- Department of Pharmacology and Toxicology, Faculty of Medicine, American University of Beirut, Beirut, Lebanon
- Departmment of Biochemistry and Molecular Genetics, Faculty of Medicine, American University of Beirut, Beirut, Lebanon
| | - Yusra Al-Dhaheri
- Department of Biology, United Arab Emirates University, Al-Ain, United Arab Emirates
| | - Ali H. Eid
- Department of Basic Medical Sciences, College of Medicine, Qatar University, Doha, Qatar
- Biomedical and Pharmaceutical Research Unit, Qatar University (QU) Health, Qatar University, Doha, Qatar
| | - Ahmed F. El-Yazbi
- Department of Pharmacology and Toxicology, Faculty of Medicine, American University of Beirut, Beirut, Lebanon
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Alexandria University, Alexandria, Egypt
- Faculty of Pharmacy, Alalamein International University, Alalamein, Egypt
- *Correspondence: Ahmed F. El-Yazbi,
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7
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Dugas LR, Lie L, Plange-Rhule J, Bedu-Addo K, Bovet P, Lambert EV, Forrester TE, Luke A, Gilbert JA, Layden BT. Gut microbiota, short chain fatty acids, and obesity across the epidemiologic transition: the METS-Microbiome study protocol. BMC Public Health 2018; 18:978. [PMID: 30081857 PMCID: PMC6090745 DOI: 10.1186/s12889-018-5879-6] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Accepted: 07/24/2018] [Indexed: 12/23/2022] Open
Abstract
BACKGROUND While some of the variance observed in adiposity and weight change within populations can be accounted for by traditional risk factors, a new factor, the gut microbiota, has recently been associated with obesity. However, the causal mechanisms through which the gut microbiota and its metabolites, short chain fatty acids (SCFAs) influence obesity are unknown, as are the individual obesogenic effects of the individual SCFAs (butyrate, acetate and propionate). This study, METS-Microbiome, proposes to examine the influence of novel risk factors, the gut microbiota and SCFAs, on obesity, adiposity and weight change in an international established cohort spanning the epidemiologic transition. METHODS The parent study; Modeling the Epidemiologic Transition Study (METS) is a well-established and ongoing prospective cohort study designed to assess the association between body composition, physical activity, and relative weight, weight gain and cardiometabolic disease risk in five diverse population-based samples in 2500 people of African descent. The cohort has been prospectively followed since 2009. Annual measures of obesity risk factors, including body composition, objectively measured physical activity and dietary intake, components which vary across the spectrum of social and economic development. In our new study; METS-Microbiome, in addition to continuing yearly measures of obesity risk, we will also measure gut microbiota and stool SCFAs in all contactable participants, and follow participants for a further 3 years, thus providing one of the largest gut microbiota population-based studies to date. DISCUSSION This new study capitalizes upon an existing, extensively well described cohort of adults of African-origin, with significant variability as a result of the widespread geographic distributions, and therefore variation in the environmental covariate exposures. The METS-Microbiome study will substantially advance the understanding of the role gut microbiota and SCFAs play in the development of obesity and provide novel obesity therapeutic targets targeting SCFAs producing features of the gut microbiota. TRIAL REGISTRATION Registered NCT03378765 Date first posted: December 20, 2017.
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Affiliation(s)
- Lara R. Dugas
- Public Health Sciences, Stritch School of Medicine, Loyola University Chicago, 2160 S. 1st Avenue, Maywood, IL 60153 USA
| | - Louise Lie
- Public Health Sciences, Stritch School of Medicine, Loyola University Chicago, 2160 S. 1st Avenue, Maywood, IL 60153 USA
| | - Jacob Plange-Rhule
- Department of Physiology, SMS, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Kweku Bedu-Addo
- Department of Physiology, SMS, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Pascal Bovet
- Institute of Social & Preventive Medicine, Lausanne University Hospital, Lausanne, Switzerland
- Ministry of Health, Republic of Seychelles, Lausanne, Switzerland
| | - Estelle V. Lambert
- Research Unit for Exercise Science and Sports Medicine, University of Cape Town, Cape Town, South Africa
| | - Terrence E. Forrester
- Solutions for Developing Countries, University of the West Indies, Mona, Kingston Jamaica
| | - Amy Luke
- Public Health Sciences, Stritch School of Medicine, Loyola University Chicago, 2160 S. 1st Avenue, Maywood, IL 60153 USA
| | - Jack A. Gilbert
- Microbiome Center, Department of Surgery, University of Chicago, Chicago, IL USA
| | - Brian T. Layden
- Division of Endocrinology, Diabetes, and Metabolism, University of Illinois at Chicago, Chicago, IL USA
- Jesse Brown Veterans Affairs Medical Center, Chicago, IL USA
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Werth S, Müller-Fielitz H, Raasch W. Obesity-stimulated aldosterone release is not related to an S1P-dependent mechanism. J Endocrinol 2017; 235:251-265. [PMID: 28970286 DOI: 10.1530/joe-16-0550] [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: 09/06/2017] [Accepted: 09/26/2017] [Indexed: 11/08/2022]
Abstract
Aldosterone has been identified as an important factor in obesity-associated hypertension. Here, we investigated whether sphingosine-1-phosphate (S1P), which has previously been linked to obesity, increases aldosterone release. S1P-induced aldosterone release was determined in NCI H295R cells in the presence of S1P receptor (S1PR) antagonists. In vivo release of S1P (100-300 µg/kgbw) was investigated in pithed, lean Sprague Dawley (SD) rats, diet-obese spontaneous hypertensive rats (SHRs), as well as in lean or obese Zucker rats. Aldosterone secretion was increased in NCI H295R cells by S1P, the selective S1PR1 agonist SEW2871 and the selective S1PR2 antagonist JTE013. Treatment with the S1PR1 antagonist W146 or fingolimod and the S1PR1/3 antagonist VPbib2319 decreased baseline and/or S1P-stimulated aldosterone release. Compared to saline-treated SD rats, plasma aldosterone increased by ~50 pg/mL after infusing S1P. Baseline levels of S1P and aldosterone were higher in obese than in lean SHRs. Adrenal S1PR expression did not differ between chow- or CD-fed rats that had the highest S1PR1 and lowest S1PR4 levels. S1P induced a short-lasting increase in plasma aldosterone in obese, but not in lean SHRs. However, 2-ANOVA did not demonstrate any difference between lean and obese rats. S1P-induced aldosterone release was also similar between obese and lean Zucker rats. We conclude that S1P is a local regulator of aldosterone production. S1PR1 agonism induces an increase in aldosterone secretion, while stimulating adrenal S1PR2 receptor suppresses aldosterone production. A significant role of S1P in influencing aldosterone secretion in states of obesity seems unlikely.
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Affiliation(s)
- Stephan Werth
- Institute of Experimental and Clinical Pharmacology and ToxicologyUniversity of Lübeck, Lübeck, Germany
| | - Helge Müller-Fielitz
- Institute of Experimental and Clinical Pharmacology and ToxicologyUniversity of Lübeck, Lübeck, Germany
- CBBM (Center of Brain, Behavior and Metabolism)Lübeck, Germany
| | - Walter Raasch
- Institute of Experimental and Clinical Pharmacology and ToxicologyUniversity of Lübeck, Lübeck, Germany
- CBBM (Center of Brain, Behavior and Metabolism)Lübeck, Germany
- DZHK (German Centre for Cardiovascular Research)partner site Hamburg/Kiel/Lübeck, Lübeck, Germany
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9
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Kosk D, Kramer H, Luke A, Camacho P, Bovet P, Rhule JP, Forrester T, Wolf M, Sempos C, Melamed ML, Dugas LR, Cooper R, Durazo-Arvizu R. Dietary factors and fibroblast growth factor-23 levels in young adults with African ancestry. J Bone Miner Metab 2017; 35:666-674. [PMID: 27942978 PMCID: PMC5711483 DOI: 10.1007/s00774-016-0804-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/02/2016] [Accepted: 10/31/2016] [Indexed: 11/30/2022]
Abstract
Fibroblast growth factor-23 (FGF23), a phosphaturic hormone secreted mainly by osteocytes, maintains serum phosphate levels within a tight range by promoting phosphaturia. Previous studies have mainly focused on the link between FGF23 levels and dietary intake of phosphate, but other dietary factors may also influence FGF23 levels. This cross-sectional study pooled three populations of young adults with African ancestry (452 in Chicago, IL, USA; 477 in Victoria, Seychelles; and 482 in Kumasi, Ghana) with estimated glomerular filtration rate >80 ml/min/1.73 m2 to examine the association of dietary factors based on two 24-h recalls with FGF23 levels measured using a C-terminal assay. Linear regression was used to examine the association between log-transformed FGF23 levels and quartiles of calorie-adjusted dietary factors with adjustment for covariates. In the pooled sample of 1411 study participants, the mean age was 35.2 (6.2) years and 45.3% were male. Median plasma C-terminal FGF23 values in relative units (RU)/ml were 59.5 [interquartile range (IQR) 44.1, 85.3] in the USA, 43.2 (IQR 33.1, 57.9) in Seychelles, and 34.0 (IQR 25.2, 50.4) in Ghana. With adjustment for covariates, increasing quartiles of calcium and animal protein and decreasing quartiles of vegetable protein, fiber, and magnesium intake were associated with significantly higher FGF23 levels compared to the lowest quartile. After further adjustment for dietary factors, significant trends in FGF23 levels were noted only for quartiles of calcium, fiber, and magnesium intake (P < 0.001). Dietary factors other than phosphate are associated with FGF23 levels in young adults.
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Affiliation(s)
- Dominique Kosk
- Department of Public Health Sciences, Loyola University Chicago, 2160 First Avenue, Maywood, IL, 60153, USA
| | - Holly Kramer
- Department of Public Health Sciences, Loyola University Chicago, 2160 First Avenue, Maywood, IL, 60153, USA.
- Division of Nephrology and Hypertension, Department of Public Health Sciences and Medicine, Loyola University Chicago, Maywood, IL, USA.
| | - Amy Luke
- Department of Public Health Sciences, Loyola University Chicago, 2160 First Avenue, Maywood, IL, 60153, USA
| | - Pauline Camacho
- Division of Endocrinology, Stritch School of Medicine, Loyola University Chicago, Maywood, IL, USA
| | - Pascal Bovet
- Institute of Social and Preventive Medicine, Lausanne University Hospital, Lausanne, Switzerland
- Ministry of Health, Victoria, Republic of Seychelles
| | - Jacob Plange Rhule
- Department of Physiology, School of Medical Sciences, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Terrence Forrester
- University of West Indies Solutions for Developing Countries, University of the West Indies Mona, Kingston, Jamaica
| | - Myles Wolf
- Division of Nephrology and Hypertension, Department of Medicine, Center for Translational Metabolism and Health, Institute for Public Health and Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Chris Sempos
- National Institutes of Health Office of Dietary Supplements, Bethesda, MD, USA
| | - Michal L Melamed
- Department of Medicine and Epidemiology and Population Health, Albert Einstein College of Medicine/Montefiore Medical Center, Bronx, NY, USA
| | - Lara R Dugas
- Department of Public Health Sciences, Loyola University Chicago, 2160 First Avenue, Maywood, IL, 60153, USA
| | - Richard Cooper
- Department of Public Health Sciences, Loyola University Chicago, 2160 First Avenue, Maywood, IL, 60153, USA
| | - Ramon Durazo-Arvizu
- Department of Public Health Sciences, Loyola University Chicago, 2160 First Avenue, Maywood, IL, 60153, USA
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Pahlavani M, Kalupahana NS, Ramalingam L, Moustaid-Moussa N. Regulation and Functions of the Renin-Angiotensin System in White and Brown Adipose Tissue. Compr Physiol 2017; 7:1137-1150. [PMID: 28915321 DOI: 10.1002/cphy.c160031] [Citation(s) in RCA: 76] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The renin angiotensin system (RAS) is a major regulator of blood pressure, fluid, and electrolyte homeostasis. RAS precursor angiotensinogen (Agt) is cleaved into angiotensin I (Ang I) and II (Ang II) by renin and angiotensin converting enzyme (ACE), respectively. Major effects of Ang II, the main bioactive peptide of this system, is mediated by G protein coupled receptors, Angiotensin Type 1 (AGTR1, AT1R) and Type 2 (AGTR2, AT2R) receptors. Further, the discovery of additional RAS peptides such as Ang 1-7 generated by the action of another enzyme ACE2 identified novel functions of this complex system. In addition to the systemic RAS, several local RAS exist in organs such as the brain, kidney, pancreas, and adipose tissue. The expression and regulation of various components of RAS in adipose tissue prompted extensive research into the role of adipose RAS in metabolic diseases. Indeed, animal studies have shown that adipose-derived Agt contributes to circulating RAS, kidney, and blood pressure regulation. Further, mice overexpressing Agt have high blood pressure and increased adiposity characterized by inflammation, adipocyte hypertrophy, and insulin resistance, which can be reversed at least in part by RAS inhibition. These findings highlight the importance of this system in energy homeostasis, especially in the context of obesity. This overview article discusses the depot-specific functions of adipose RAS, genetic and pharmacological manipulations of RAS, and its applications to adipogenesis, thermogenesis, and overall energy homeostasis. © 2017 American Physiological Society. Compr Physiol 7:1137-1150, 2017.
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Affiliation(s)
- Mandana Pahlavani
- Department of Nutritional Sciences and Obesity Research Cluster, Texas Tech University, Lubbock, Texas, USA
| | - Nishan S Kalupahana
- Department of Nutritional Sciences and Obesity Research Cluster, Texas Tech University, Lubbock, Texas, USA.,Department of Nutritional Sciences and Obesity Research Cluster, Texas Tech University, Lubbock, Texas, USA
| | - Latha Ramalingam
- Department of Nutritional Sciences and Obesity Research Cluster, Texas Tech University, Lubbock, Texas, USA
| | - Naima Moustaid-Moussa
- Department of Nutritional Sciences and Obesity Research Cluster, Texas Tech University, Lubbock, Texas, USA
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Bruce EB, de Kloet AD. The intricacies of the renin-angiotensin-system in metabolic regulation. Physiol Behav 2017; 178:157-165. [PMID: 27887998 PMCID: PMC5600901 DOI: 10.1016/j.physbeh.2016.11.020] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2016] [Revised: 11/15/2016] [Accepted: 11/18/2016] [Indexed: 12/15/2022]
Abstract
Over recent years, the renin-angiotensin-system (RAS), which is best-known as an endocrine system with established roles in hydromineral balance and blood pressure control, has emerged as a fundamental regulator of many additional physiological and pathophysiological processes. In this manuscript, we celebrate and honor Randall Sakai's commitment to his trainees, as well as his contribution to science. Scientifically, Randall made many notable contributions to the recognition of the RAS's roles in brain and behavior. His interests, in this regard, ranged from its traditionally-accepted roles in hydromineral balance, to its less-appreciated functions in stress responses and energy metabolism. Here we review the current understanding of the role of the RAS in the regulation of metabolism. In particular, the opposing actions of the RAS within adipose tissue vs. its actions within the brain are discussed.
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Affiliation(s)
- Erin B Bruce
- Department of Pharmacodynamics, College of Pharmacy, University of Florida, United States
| | - Annette D de Kloet
- Department of Physiology and Functional Genomics, College of Medicine, University of Florida, United States.
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Sharma AM, Engeli S. The renin-angiotensin system in obesity hypertension. J Renin Angiotensin Aldosterone Syst 2017; 2:S114-S119. [PMID: 28095231 DOI: 10.1177/14703203010020012001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
- Arya M Sharma
- Franz-Volhard-Klinik at the Max-Delbrück-Center for Molecular Medicine, Universitätsklinikum Charité, Humboldt Universität zu Berlin, Germany,
| | - Stefan Engeli
- Franz-Volhard-Klinik at the Max-Delbrück-Center for Molecular Medicine, Universitätsklinikum Charité, Humboldt Universität zu Berlin, Germany
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Guo H, Li H, Wang B, Ding W, Ling L, Yang M, Gu Y, Niu J. Protective Effects of Glucagon-Like Peptide-1 Analog on Renal Tubular Injury in Mice on High-Fat Diet. Cell Physiol Biochem 2017; 41:1113-1124. [DOI: 10.1159/000464118] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2016] [Accepted: 01/04/2017] [Indexed: 12/22/2022] Open
Abstract
Aims: The study aimed to investigate the renoprotective effect of glucagon-like peptide-1 (GLP-1) against renal tubular injury in C57BL/6 mice induced by a high-fat diet (HFD). Methods: Twenty C57BL/6 mice were fed HFD for 12 weeks. Ten of these mice were treated with GLP-1 at 200 µg/kg subcutaneously twice daily for 4 weeks (HFDG group), and the other ten mice received vehicle only (HFD group). Ten mice fed standard rodent chow served as controls (Con group). Body weight, kidney weight, food intake, and systolic blood pressure were measured. The expression of endoplasmic reticulum stress (ERS) markers (BIP, p-eIF2α, ATF4, and CHOP) and apoptosis in the kidney were examined utilizing western blotting, immunohistochemistry and TUNEL, respectively. Angiotensin II and angiotensin II type 1 receptor (AT1R) were examined by ELISA. Human proximal tubule epithelial cells (HK2) were treated with GLP-1(150 nM) followed by treatment with palmitic acid (500 nM [PA]) for 24 h. HK2 cells treated with BSA were used as controls. The protein levels of ERS markers, apoptosis-associated protein, and AT1R were measured by western blotting. Results: Increase of body weight, food intake, and systolic blood pressure was less pronounced in GLP-1 treated HFDG mice compared to HFD mice. The levels of ERS markers (BIP, p-eIF2α, ATF4, and CHOP) and apoptosis decreased following GLP-1 treatment in vivo and in vitro (p<0.05). Increased AT1R induced by HFD and PA were blocked with GLP-1 treatment. In contrast, the level of angiotensin II after GLP-1 treatment was not significantly different between the HFD and HFDG mice. Conclusion: The study indicated that saturated fatty acids induced ERS and apoptosis in the kidney and increased AT1R expression. GLP-1 treatment exerted renoprotective effects against saturated fatty acid-induced kidney tubular cell ERS and apoptosis together with inhibition of AT1R expression in vivo and in vitro.
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Pitra S, Feng Y, Stern JE. Mechanisms underlying prorenin actions on hypothalamic neurons implicated in cardiometabolic control. Mol Metab 2016; 5:858-868. [PMID: 27688999 PMCID: PMC5034613 DOI: 10.1016/j.molmet.2016.07.010] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Revised: 07/26/2016] [Accepted: 07/27/2016] [Indexed: 02/07/2023] Open
Abstract
Background Hypertension and obesity are highly interrelated diseases, being critical components of the metabolic syndrome. Despite the growing prevalence of this syndrome in the world population, efficient therapies are still missing. Thus, identification of novel targets and therapies are warranted. An enhanced activity of the hypothalamic renin-angiotensin system (RAS), including the recently discovered prorenin (PR) and its receptor (PRR), has been implicated as a common mechanism underlying aberrant sympatho-humoral activation that contributes to both metabolic and cardiovascular dysregulation in the metabolic syndrome. Still, the identification of precise neuronal targets, cellular mechanisms and signaling pathways underlying PR/PRR actions in cardiovascular- and metabolic related hypothalamic nuclei remain unknown. Methods and results Using a multidisciplinary approach including patch-clamp electrophysiology, live calcium imaging and immunohistochemistry, we aimed to elucidate cellular mechanisms underlying PR/PRR actions within the hypothalamic supraoptic (SON) and paraventricular nucleus (PVN), key brain areas previously involved in cardiometabolic regulation. We show for the first time that PRR is expressed in magnocellular neurosecretory cells (MNCs), and to a lesser extent, in presympathetic PVN neurons (PVNPS). Moreover, we show that while PRR activation efficiently stimulates the firing activity of both MNCs and PVNPS neurons, these effects involved AngII-independent and AngII-dependent mechanisms, respectively. In both cases however, PR excitatory effects involved an increase in intracellular Ca2+ levels and a Ca2+-dependent inhibition of a voltage-gated K+ current. Conclusions We identified novel neuronal targets and cellular mechanisms underlying PR/PRR actions in critical hypothalamic neurons involved in cardiometabolic regulation. This fundamental mechanistic information regarding central PR/PRR actions is essential for the development of novel RAS-based therapeutic targets for the treatment of cardiometabolic disorders in obesity and hypertension. PRR is expressed in SON and PVN neurosecretory and presympathetic neurons. PRR activation stimulates firing activity of SON and PVN neurons. PR/PRR effects on neurosecretory neurons are AngII-independent. PR/PRR effects on presympathetic neurons are AngII-dependent. PR inhibits a voltage-gated K+ current in a Ca2+-dependent manner.
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Affiliation(s)
- Soledad Pitra
- Department of Physiology, Medical College of Georgia, Augusta University, United States
| | - Yumei Feng
- Departments of Pharmacology, Physiology and Cell Biology, Center for Cardiovascular Research, University of Nevada School of Medicine, United States
| | - Javier E Stern
- Department of Physiology, Medical College of Georgia, Augusta University, United States.
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Dugas LR, Fuller M, Gilbert J, Layden BT. The obese gut microbiome across the epidemiologic transition. Emerg Themes Epidemiol 2016; 13:2. [PMID: 26759600 PMCID: PMC4710045 DOI: 10.1186/s12982-015-0044-5] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2015] [Accepted: 12/15/2015] [Indexed: 12/13/2022] Open
Abstract
The obesity epidemic has emerged over the past few decades and is thought to be a result of both genetic and environmental factors. A newly identified factor, the gut microbiota, which is a bacterial ecosystem residing within the gastrointestinal tract of humans, has now been implicated in the obesity epidemic. Importantly, this bacterial community is impacted by external environmental factors through a variety of undefined mechanisms. We focus this review on how the external environment may impact the gut microbiota by considering, the host’s geographic location ‘human geography’, and behavioral factors (diet and physical activity). Moreover, we explore the relationship between the gut microbiota and obesity with these external factors. And finally, we highlight here how an epidemiologic model can be utilized to elucidate causal relationships between the gut microbiota and external environment independently and collectively, and how this will help further define this important new factor in the obesity epidemic.
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Affiliation(s)
- Lara R Dugas
- Public Health Sciences, Stritch School of Medicine, Loyola University Chicago, 2160 S. 1st Ave, Maywood, IL 60153 USA
| | - Miles Fuller
- Division of Endocrinology, Metabolism and Molecular Medicine, Northwestern University, Evanston, USA
| | - Jack Gilbert
- Argonne National Laboratory, Biosciences Department, Institute for Genomic and Systems Biology, 9700 South Cass Avenue, Argonne, IL 60439 USA ; Department of Ecology and Evolution, University of Chicago, 1101 E 57th Street, Chicago, IL 60637 USA ; Marine Biological Laboratory, 7 MBL Street, Woods Hole, MA 02543 USA ; College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, 310058 China
| | - Brian T Layden
- Division of Endocrinology, Metabolism and Molecular Medicine, Northwestern University, Evanston, USA ; Jesse Brown Veterans Affairs Medical Center, Chicago, IL USA
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Smith PM, Hindmarch CCT, Murphy D, Ferguson AV. AT1 receptor blockade alters nutritional and biometric development in obesity-resistant and obesity-prone rats submitted to a high fat diet. Front Psychol 2014; 5:832. [PMID: 25120524 PMCID: PMC4114257 DOI: 10.3389/fpsyg.2014.00832] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2014] [Accepted: 07/12/2014] [Indexed: 12/16/2022] Open
Abstract
Obesity is a chronic metabolic condition with important public health implications associated with numerous co-morbidities including cardiovascular disease, insulin resistance, and hypertension. The renin angiotensin system (RAS), best known for its involvement in cardiovascular control and body fluid homeostasis has, more recently, been implicated in regulation of energy balance. Interference with the RAS (genetically or pharmacologically) has been shown to influence body weight gain. In this study we investigated the effects of systemic AT1 receptor blockade using losartan on ingestive behaviors and weight gain in diet induced obese (DIO) rats. Prior to losartan administration (30 mg/kg/day) body weight gain remained constant within the DIO animals (3.6 ± 0.3 g/day, n = 8), diet resistant (DR) animals (2.1 ± 0.6 g/day, n = 8) and in the age-matched chow fed control (CHOW) animals (2.8 ± 0.3 g/day, n = 8), Losartan administration abolished body weight gain in animals fed a high fat diet (DIO: -0.4 ± 0.7 g/day, n = 8; and DR: -0.8 ± 0.3 g/day, n = 8) while chow fed animals continued to gain weight (2.2 ± 0.3 g/day, n = 8) as they had previously to oral administration of losartan. This decrease in daily body weight gain was accompanied by a decrease in food intake in the HFD fed animals. Following the removal of losartan, both the DIO and DR animals again showed daily increases in body weight gain and food intake which were similar to control values. Our data demonstrate that oral losartan administration attenuates body weight gain in animals fed a HFD whether the animal is obese (DIO) or not DR while having no effect on body weight gain in age-matched chow fed animals suggesting a protective effect of losartan against body weight gain while on a HFD.
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Affiliation(s)
- Pauline M Smith
- Department of Biomedical and Molecular Sciences, Queen's University Kingston, ON, Canada
| | - Charles C T Hindmarch
- The Henry Wellcome Laboratories for Integrative Neuroscience and Endocrinology, University of Bristol Bristol, UK ; Department of Physiology, Faculty of Medicine, University of Malaya Kuala Lumpur, Malaysia
| | - David Murphy
- The Henry Wellcome Laboratories for Integrative Neuroscience and Endocrinology, University of Bristol Bristol, UK ; Department of Physiology, Faculty of Medicine, University of Malaya Kuala Lumpur, Malaysia
| | - Alastair V Ferguson
- Department of Biomedical and Molecular Sciences, Queen's University Kingston, ON, Canada
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17
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Kim JH, Jung ES, Kim CH, Youn H, Kim HR. Genetic associations of body composition, flexibility and injury risk with ACE, ACTN3 and COL5A1 polymorphisms in Korean ballerinas. J Exerc Nutrition Biochem 2014; 18:205-14. [PMID: 25566457 PMCID: PMC4241924 DOI: 10.5717/jenb.2014.18.2.205] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2014] [Revised: 05/24/2014] [Accepted: 05/30/2014] [Indexed: 11/04/2022] Open
Abstract
PURPOSE The purpose of this study was to exam the association of body composition, flexibility, and injury risk to genetic polymorphisms including ACE ID, ACTN3 RX, and COL5A1 polymorphisms in ballet dancers in Korea. METHODS For the purpose of this study, elite ballerinas (n = 97) and normal female adults (n = 203) aged 18 to 39 were recruited and these participants were tested for body weight, height, body fat, fat free mass, flexibility, injury risks on the joints and gene polymorphisms (ACE, ACTN3, COL5A1 polymorphism). RESULTS As results, the ACE DD genotype in ballerinas was associated with higher body fat and percentage of body fat than the ACE II and ID genotypes (p < 0.05). In the study on the ACTN3 polymorphism and ballerinas, the XX genotype in ballerinas had lower body weight and lower fat-free mass than the RR and RX genotype (p < 0.005). Also, the means of sit and reach test for flexibility was lower in the ACTN3 XX genotype of ballerinas than the RR and RX genotype of ballerinas (p < 0.05). Among the sports injuries, the ankle injury of the XX-genotyped ballerinas was in significantly more prevalence than the RR and XX-genotyped ballerinas (p < 0.05). According to the odd ratio analysis, XX-genotyped ballerinas have the injury risk on the ankle about 4.7 (95% CI: 1.6~13.4, p < 0.05) times more than the RR and RX-genotyped ballerinas. Meanwhile, the COL5A1 polymorphism in ballerinas has no association with any factors including flexibility and injury risks. CONCLUSION In conclusion, ACE polymorphism and ACTN3 polymorphism were associated with ballerinas' performance capacity; COL5A1 was not associated with any factors of performance of Ballerinas. The results suggested that the ACE DD genotype is associated with high body fat, the ACTN3 XX genotype is associated with low fat-free mass, low flexibility, and higher risk of ankle-joint injury.
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Affiliation(s)
- Jun Ho Kim
- School of Dance, Kyunghee University, Seoul, Korea
| | - Eun Sun Jung
- School of Dance, Kyunghee University, Seoul, Korea
| | - Chul-Hyun Kim
- Department of Sports Medicine, Soonchunhyang University, Asan, Korea
| | - Hyeon Youn
- Department of Judo, Yong In University, Yong In, Korea
| | - Hwa Rye Kim
- School of Dance, Kyunghee University, Seoul, Korea
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18
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Luke A, Bovet P, Plange-Rhule J, Forrester TE, Lambert EV, Schoeller DA, Dugas LR, Durazo-Arvizu RA, Shoham DA, Cao G, Brage S, Ekelund U, Cooper RS. A mixed ecologic-cohort comparison of physical activity & weight among young adults from five populations of African origin. BMC Public Health 2014; 14:397. [PMID: 24758286 PMCID: PMC4031970 DOI: 10.1186/1471-2458-14-397] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2013] [Accepted: 03/30/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Examination of patterns and intensity of physical activity (PA) across cultures where obesity prevalence varies widely provides insight into one aspect of the ongoing epidemiologic transition. The primary hypothesis being addressed is whether low levels of PA are associated with excess weight and adiposity. METHODS We recruited young adults from five countries (500 per country, 2500 total, ages 25-45 years), spanning the range of obesity prevalence. Men and women were recruited from a suburb of Chicago, Illinois, USA; urban Jamaica; rural Ghana; peri-urban South Africa; and the Seychelles. PA was measured using accelerometry and expressed as minutes per day of moderate-to-vigorous activity or sedentary behavior. RESULTS Obesity (BMI ≥ 30) prevalence ranged from 1.4% (Ghanaian men) to 63.8% (US women). South African men were the most active, followed by Ghanaian men. Relatively small differences were observed across sites among women; however, women in Ghana accumulated the most activity. Within site-gender sub-groups, the correlation of activity with BMI and other measures of adiposity was inconsistent; the combined correlation across sites was -0.17 for men and -0.11 for women. In the ecological analysis time spent in moderate-to-vigorous activity was inversely associated with BMI (r = -0.71). CONCLUSION These analyses suggest that persons with greater adiposity tend to engage in less PA, although the associations are weak and the direction of causality cannot be inferred because measurements are cross-sectional. Longitudinal data will be required to elucidate direction of association.
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Affiliation(s)
- Amy Luke
- Stritch School of Medicine, Loyola University Chicago, Maywood, IL, USA
| | - Pascal Bovet
- Institute of Social & Preventive Medicine, Lausanne University Hospital, Ministry of Health, Republic of Seychelles, Lausanne, Switzerland
| | | | - Terrence E Forrester
- Tropical Medicine Research Institute, University of the West Indies, Mona, Kingston, Jamaica
| | - Estelle V Lambert
- Research Unit for Exercise Science and Sports Medicine, University of Cape Town, Cape Town, South Africa
| | | | - Lara R Dugas
- Stritch School of Medicine, Loyola University Chicago, Maywood, IL, USA
| | | | - David A Shoham
- Stritch School of Medicine, Loyola University Chicago, Maywood, IL, USA
| | - Guichan Cao
- Stritch School of Medicine, Loyola University Chicago, Maywood, IL, USA
| | - Soren Brage
- MRC Epidemiology Unit, Addenbrooke’s Hospital, Cambridge, UK
| | - Ulf Ekelund
- MRC Epidemiology Unit, Addenbrooke’s Hospital, Cambridge, UK
- Department of Sport Medicine, Norwegian School of Sport Sciences, Oslo, Norway
| | - Richard S Cooper
- Stritch School of Medicine, Loyola University Chicago, Maywood, IL, USA
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Obesity induces neuroinflammation mediated by altered expression of the renin-angiotensin system in mouse forebrain nuclei. Physiol Behav 2014; 136:31-8. [PMID: 24508821 DOI: 10.1016/j.physbeh.2014.01.016] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2013] [Revised: 01/21/2014] [Accepted: 01/27/2014] [Indexed: 12/26/2022]
Abstract
Obesity is a widespread health concern that is associated with an increased prevalence of hypertension and cardiovascular disease. Both obesity and hypertension have independently been associated with increased levels of inflammatory cytokines and immune cells within specific brain regions, as well as increased activity of the renin-angiotensin system (RAS). To test the hypothesis that high-fat diet (HFD) induced obesity leads to an angiotensin-II (Ang-II)-dependent increase in inflammatory cells within specific forebrain regions that are important for cardiovascular regulation, we first assessed microglial activation, astrocyte activation, inflammation and RAS component gene expression within selected metabolic and cardiovascular control centers of the forebrain in adult male C57BL/6 mice given either a HFD or a low-fat diet (LFD) for 8weeks. Subsequently, we assessed the necessity of the paraventricular nucleus of the hypothalamus (PVN) angiotensin type-1a (AT1a) receptor for these responses by using the Cre/lox system in mice to selectively delete the AT1a receptor from the PVN. These studies reveal that in addition to the arcuate nucleus of the hypothalamus (ARC), the PVN and the subfornical organ (SFO), two brain regions that are known to regulate blood pressure and energy balance, also initiate proinflammatory responses after the consumption of a diet high in fat. They further indicate that some, but not all, of these responses are reversed upon deletion of AT1a specifically within the PVN.
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Lemes VAF, Neves AL, Guazzelli IC, Frazzatto E, Nicolau C, Corrêa-Giannella ML, Velho G, Villares SMF. Angiotensin converting enzyme insertion/deletion polymorphism is associated with increased adiposity and blood pressure in obese children and adolescents. Gene 2013; 532:197-202. [PMID: 24076353 DOI: 10.1016/j.gene.2013.09.065] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2013] [Revised: 07/14/2013] [Accepted: 09/18/2013] [Indexed: 12/24/2022]
Abstract
BACKGROUND The insertion/deletion polymorphism in the gene encoding the angiotensin-converting enzyme (ACE I/D) was associated with arterial hypertension and obesity in adults, but the data in children are scarce and yielded contrasting results. We assessed the impact of the ACE I/D on blood pressure and obesity related traits in a Brazilian cohort of obese children and adolescents. METHODS AND RESULTS ACE I/D was genotyped in 320 obese children and adolescents (64% of girls) aged 7-16years, referred for a weight-loss program. We observed an association of the D-allele with blood pressure and with pre-hypertension/hypertension in boys (odds ratio 2.44, 95% C.I. 1.34-4.68, p=0.005 for a codominant model). The D-allele, insulin resistance and body fat mass had independent and additive effects and explained 14% of the variance of pre-hypertension/hypertension. The BMI, waist circumference, and body fat mass were significantly higher in DD/ID boys than in II boys (p<0.005). Allelic associations with obesity related traits were independent of the association with blood pressure. No genotype associations were observed in girls. CONCLUSIONS The D-allele of the ACE I/D polymorphism was associated with arterial hypertension and with obesity related traits in boys, but not in girls, in a cohort of obese children and adolescents. These associations were independent of each other, as well as of the effects of other confounding traits such as insulin secretion, insulin sensitivity and glucose tolerance. Our results are in agreement with experimental evidences suggesting that the renin-angiotensin system plays a role in the regulation of visceral adipose tissue accumulation.
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Affiliation(s)
- Vinícius A F Lemes
- Laboratório de Endocrinologia Celular e Molecular (LIM-25), Faculdade de Medicina da Universidade de São Paulo (FMUSP), São Paulo, SP, Brazil
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Angiotensin type 1a receptors in the paraventricular nucleus of the hypothalamus protect against diet-induced obesity. J Neurosci 2013; 33:4825-33. [PMID: 23486953 DOI: 10.1523/jneurosci.3806-12.2013] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Obesity is associated with increased levels of angiotensin-II (Ang-II), which activates angiotensin type 1a receptors (AT1a) to influence cardiovascular function and energy homeostasis. To test the hypothesis that specific AT1a within the brain control these processes, we used the Cre/lox system to delete AT1a from the paraventricular nucleus of the hypothalamus (PVN) of mice. PVN AT1a deletion did not affect body mass or adiposity when mice were maintained on standard chow. However, maintenance on a high-fat diet revealed a gene by environment interaction whereby mice lacking AT1a in the PVN had increased food intake and decreased energy expenditure that augmented body mass and adiposity relative to controls. Despite this increased adiposity, PVN AT1a deletion reduced systolic blood pressure, suggesting that this receptor population mediates the positive correlation between adiposity and blood pressure. Gene expression studies revealed that PVN AT1a deletion decreased hypothalamic expression of corticotrophin-releasing hormone and oxytocin, neuropeptides known to control food intake and sympathetic nervous system activity. Whole-cell patch-clamp recordings confirmed that PVN AT1a deletion eliminates responsiveness of PVN parvocellular neurons to Ang-II, and suggest that Ang-II responsiveness is increased in obese wild-type mice. Central inflammation is associated with metabolic and cardiovascular disorders and PVN AT1a deletion reduced indices of hypothalamic inflammation. Collectively, these studies demonstrate that PVN AT1a regulate energy balance during environmental challenges that promote metabolic and cardiovascular pathologies. The implication is that the elevated Ang-II that accompanies obesity serves as a negative feedback signal that activates PVN neurons to alleviate weight gain.
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Neuroimmune communication in hypertension and obesity: a new therapeutic angle? Pharmacol Ther 2013; 138:428-40. [PMID: 23458610 DOI: 10.1016/j.pharmthera.2013.02.005] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2013] [Accepted: 02/12/2013] [Indexed: 12/13/2022]
Abstract
Hypertension is an epidemic health concern and a major risk factor for the development of cardiovascular disease. Although there are available treatment strategies for hypertension, numerous hypertensive patients do not have their clinical symptoms under control and it is imperative that new avenues to treat or prevent high blood pressure in these patients are developed. It is well established that increases in sympathetic nervous system (SNS) outflow and enhanced renin-angiotensin system (RAS) activity are common features of hypertension and various pathological conditions that predispose individuals to hypertension. More recently, hypertension has also become recognized as an immune condition and accumulating evidence suggests that interactions between the RAS, SNS and immune systems play a role in blood pressure regulation. This review summarizes what is known about the interconnections between the RAS, SNS and immune systems in the neural regulation of blood pressure. Based on the reviewed studies, a model for RAS/neuroimmune interactions during hypertension is proposed and the therapeutic potential of targeting RAS/neuroimmune interactions in hypertensive patients is discussed. Special emphasis is placed on the applicability of the proposed model to obesity-related hypertension.
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Kooffreh ME, Anumudu CI, Akpan EE, Ikpeme EV, Lava Kumar P. A study of the M235T variant of the angiotensinogen gene and hypertension in a sample population of Calabar and Uyo, Nigeria. EGYPTIAN JOURNAL OF MEDICAL HUMAN GENETICS 2013. [DOI: 10.1016/j.ejmhg.2012.06.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
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Müller-Fielitz H, Lau M, Jöhren O, Stellmacher F, Schwaninger M, Raasch W. Blood pressure response to angiotensin II is enhanced in obese Zucker rats and is attributed to an aldosterone-dependent mechanism. Br J Pharmacol 2012; 166:2417-29. [PMID: 22452651 DOI: 10.1111/j.1476-5381.2012.01953.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND AND PURPOSE Plasma aldosterone levels correlate positively with obesity, suggesting a link between the hypertension associated with obesity and increased mineralocorticoid levels. We tested the hypothesis that aldosterone is involved in the BP response to angiotensin II (AngII) in obese rats. EXPERIMENTAL APPROACH Lean (LZR) and obese (OZR) Zucker rats were treated with AngII (9 µg·h(-1) ; 4 weeks), and BP and plasma AngII and aldosterone were determined. KEY RESULTS Chronic AngII increased the BP in OZR markedly more so than in LZR. Plasma AngII levels in LZR and OZR were similar after AngII treatment. The AngII stimulated a rise in plasma aldosterone that was sixfold more in OZR than in LZR. The thickness of the zona glomerulosa of the adrenal glands was selectively increased by AngII in OZR. Adrenal mRNA levels of CYP11B2 aldosterone synthase and the AT(1B) receptor were selectively increased in AngII-treated OZR. The BP response to chronic AngII stimulation was diminished in OZR after adrenalectomy when plasma aldosterone was absent. Acute bolus injections of AngII did not increase the BP response or aldosterone release in OZR. CONCLUSIONS AND IMPLICATIONS The AngII-induced BP response is enhanced in obesity and this is associated with a specific increase in circulating aldosterone. Due to the AngII-induced growth of the zona glomerulosa in OZR, the AT(1B) receptors and aldosterone synthase may be selectively enhanced in obesity under concomitant AngII stimulation, increasing the adrenal synthesis of aldosterone. Our results confirm functionally that aldosterone plays a major role in obesity-related hypertension.
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Affiliation(s)
- Helge Müller-Fielitz
- Institute of Experimental and Clinical Pharmacology and Toxicology, University of Lübeck, Germany
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Xu XJ, Gauthier MS, Hess DT, Apovian CM, Cacicedo JM, Gokce N, Farb M, Valentine RJ, Ruderman NB. Insulin sensitive and resistant obesity in humans: AMPK activity, oxidative stress, and depot-specific changes in gene expression in adipose tissue. J Lipid Res 2012; 53:792-801. [PMID: 22323564 DOI: 10.1194/jlr.p022905] [Citation(s) in RCA: 152] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
We previously reported that adenosine monophosphate-activated protein kinase (AMPK) activity is lower in adipose tissue of morbidly obese individuals who are insulin resistant than in comparably obese people who are insulin sensitive. However, the number of patients and parameters studied were small. Here, we compared abdominal subcutaneous, epiploic, and omental fat from 16 morbidly obese individuals classified as insulin sensitive or insulin resistant based on the homeostatic model assessment of insulin resistance. We confirmed that AMPK activity is diminished in the insulin resistant group. A custom PCR array revealed increases in mRNA levels of a wide variety of genes associated with inflammation and decreases in PGC-1α and Nampt in omental fat of the insulin resistant group. In contrast, subcutaneous abdominal fat of the same patients showed increases in PTP-1b, VEGFa, IFNγ, PAI-1, and NOS-2 not observed in omental fat. Only angiotensinogen and CD4(+) mRNA levels were increased in both depots. Surprisingly, TNFα was only increased in epiploic fat, which otherwise showed very few changes. Protein carbonyl levels, a measure of oxidative stress, were increased in all depots. Thus, adipose tissues of markedly obese insulin resistant individuals uniformly show decreased AMPK activity and increased oxidative stress compared with insulin sensitive patients. However, most changes in gene expression appear to be depot-specific.
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Affiliation(s)
- X Julia Xu
- Diabetes and Metabolism Unit, Section of Endocrinology, Boston University School of Medicine, Boston, MA 02118, USA
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Kalupahana NS, Moustaid-Moussa N. The renin-angiotensin system: a link between obesity, inflammation and insulin resistance. Obes Rev 2012; 13:136-49. [PMID: 22034852 DOI: 10.1111/j.1467-789x.2011.00942.x] [Citation(s) in RCA: 189] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The renin-angiotensin system (RAS) is classically known for its role in regulation of blood pressure, fluid and electrolyte balance. Recently, several local RASs in organs such as brain, heart, pancreas and adipose tissue have also been identified. Evidence from clinical trials suggests that in addition to anti-hypertensive effects, pharmacological inhibition of RAS also provides protection against the development of type-2 diabetes. Moreover, animal models with targeted inactivation of RAS genes exhibit improved insulin sensitivity and are protected from high-fat diet-induced obesity and insulin resistance. Because there is evidence for RAS overactivation in obesity, it is possible that RAS is a link between obesity and insulin resistance. This review summarizes the evidence and mechanistic insights on the associations between RAS, obesity and insulin resistance, with special emphasis on the role of adipose tissue RAS in the pathogenesis of metabolic derangements in obesity.
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Affiliation(s)
- N S Kalupahana
- Obesity Research Center, The University of Tennessee, Knoxville, TN 37996-4588, USA
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Putnam K, Shoemaker R, Yiannikouris F, Cassis LA. The renin-angiotensin system: a target of and contributor to dyslipidemias, altered glucose homeostasis, and hypertension of the metabolic syndrome. Am J Physiol Heart Circ Physiol 2012; 302:H1219-30. [PMID: 22227126 DOI: 10.1152/ajpheart.00796.2011] [Citation(s) in RCA: 159] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The renin-angiotensin system (RAS) is an important therapeutic target in the treatment of hypertension. Obesity has emerged as a primary contributor to essential hypertension in the United States and clusters with other metabolic disorders (hyperglycemia, hypertension, high triglycerides, low HDL cholesterol) defined within the metabolic syndrome. In addition to hypertension, RAS blockade may also serve as an effective treatment strategy to control impaired glucose and insulin tolerance and dyslipidemias in patients with the metabolic syndrome. Hyperglycemia, insulin resistance, and/or specific cholesterol metabolites have been demonstrated to activate components required for the synthesis [angiotensinogen, renin, angiotensin-converting enzyme (ACE)], degradation (ACE2), or responsiveness (angiotensin II type 1 receptors, Mas receptors) to angiotensin peptides in cell types (e.g., pancreatic islet cells, adipocytes, macrophages) that mediate specific disorders of the metabolic syndrome. An activated local RAS in these cell types may contribute to dysregulated function by promoting oxidative stress, apoptosis, and inflammation. This review will discuss data demonstrating the regulation of components of the RAS by cholesterol and its metabolites, glucose, and/or insulin in cell types implicated in disorders of the metabolic syndrome. In addition, we discuss data supporting a role for an activated local RAS in dyslipidemias and glucose intolerance/insulin resistance and the development of hypertension in the metabolic syndrome. Identification of an activated RAS as a common thread contributing to several disorders of the metabolic syndrome makes the use of angiotensin receptor blockers and ACE inhibitors an intriguing and novel option for multisymptom treatment.
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Affiliation(s)
- Kelly Putnam
- Graduate Center for Nutritional Sciences, University of Kentucky, Lexington, 40536-0200, USA
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de Kloet AD, Krause EG, Scott KA, Foster MT, Herman JP, Sakai RR, Seeley RJ, Woods SC. Central angiotensin II has catabolic action at white and brown adipose tissue. Am J Physiol Endocrinol Metab 2011; 301:E1081-91. [PMID: 21862725 PMCID: PMC3233774 DOI: 10.1152/ajpendo.00307.2011] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Considerable evidence implicates the renin-angiotensin system (RAS) in the regulation of energy balance. To evaluate the role of the RAS in the central nervous system regulation of energy balance, we used osmotic minipumps to chronically administer angiotensin II (Ang II; icv; 0.7 ng/min for 24 days) to adult male Long-Evans rats, resulting in reduced food intake, body weight gain, and adiposity. The decrease in body weight and adiposity occurred relative to both ad libitum- and pair-fed controls, implying that reduced food intake in and of itself does not underlie all of these effects. Consistent with this, rats administered Ang II had increased whole body heat production and oxygen consumption. Additionally, chronic icv Ang II increased uncoupling protein-1 and β(3)-adrenergic receptor expression in brown adipose tissue and β3-adrenergic receptor expression in white adipose tissue, which is suggestive of enhanced sympathetic activation and thermogenesis. Chronic icv Ang II also increased hypothalamic agouti-related peptide and decreased hypothalamic proopiomelanocortin expression, consistent with a state of energy deficit. Moreover, chronic icv Ang II increased the anorectic corticotrophin- and thyroid-releasing hormones within the hypothalamus. These results suggest that Ang II acts in the brain to promote negative energy balance and that contributing mechanisms include an alteration in the hypothalamic circuits regulating energy balance, a decrease in food intake, an increase in energy expenditure, and an increase in sympathetic activation of brown and white adipose tissue.
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MESH Headings
- Adipose Tissue, Brown/drug effects
- Adipose Tissue, Brown/metabolism
- Adipose Tissue, White/drug effects
- Adipose Tissue, White/metabolism
- Angiotensin II/administration & dosage
- Angiotensin II/pharmacology
- Animals
- Body Weight/drug effects
- Brain/drug effects
- Dose-Response Relationship, Drug
- Down-Regulation/drug effects
- Drug Evaluation, Preclinical
- Eating/drug effects
- Infusion Pumps, Implantable
- Infusions, Intraventricular
- Infusions, Subcutaneous
- Male
- Metabolism/drug effects
- Rats
- Rats, Long-Evans
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Affiliation(s)
- Annette D de Kloet
- Department of Physiology and Functional Genomics, College of Medicine, University of Florida, Gainesville, Florida 32611, USA.
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29
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Sympathetic nervous system in obesity-related hypertension: mechanisms and clinical implications. Hypertens Res 2011; 35:4-16. [PMID: 22048570 DOI: 10.1038/hr.2011.173] [Citation(s) in RCA: 135] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Obesity markedly increases the risk of hypertension and cardiovascular disease, which may be related to activation of the sympathetic nervous system (SNS). Sympathetic overactivity directly and indirectly contributes to blood pressure (BP) elevation in obesity, including stimulation of the renin-angiotensin-aldosterone system (RAAS). The adipocyte-derived peptide leptin suppresses appetite, increases thermogenesis, but also raises SNS activity and BP. Obese individuals exhibit hyperleptinemia but are resistant to its appetite-suppressing actions. Interestingly, animal models of obesity exhibit preserved sympathoexcitatory and pressor actions of leptin, despite resistance to its anorexic and metabolic actions, suggesting selective leptin resistance. Disturbance of intracellular signaling at specific hypothalamic neural networks appears to underlie selective leptin resistance. Delineation of these pathways should lead to novel approaches to treatment. In the meantime, treatment of obesity-hypertension has relied on antihypertensive drugs. Although sympathetic blockade is mechanistically attractive in obesity-hypertension, in practice its effects are disappointing because of adverse metabolic effects and inferior outcomes. On the basis of subgroup analyses of obese patients in large randomized clinical trials, drugs such as diuretics and RAAS blockers appear superior in preventing cardiovascular events in obesity--hypertension. An underused alternative approach to obesity-hypertension is induction of weight loss, which reduces circulating leptin and insulin, partially reverses resistance to these hormones, decreases sympathetic activation and improves BP and other risk factors. Though weight loss induced by lifestyle is often modest and transient, carefully selected pharmacological weight loss therapies can produce substantial and sustained antihypertensive effects additive to lifestyle interventions.
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30
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Premaratna SD, Manickam E, Begg DP, Rayment DJ, Hafandi A, Jois M, Cameron-Smith D, Weisinger RS. Angiotensin-converting enzyme inhibition reverses diet-induced obesity, insulin resistance and inflammation in C57BL/6J mice. Int J Obes (Lond) 2011; 36:233-43. [PMID: 21556046 DOI: 10.1038/ijo.2011.95] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
AIM Angiotensin-converting enzyme (ACE) inhibition can reduce the body weight of mice maintained on a high-fat diet. The current study examined the effect of the ACE inhibitor, captopril (CAP), on the reversal of diet-induced obesity (DIO), insulin resistance and inflammation in mice. MATERIALS AND METHODS DIO was produced in C57BL/6J male mice (n=30) by maintaining animals on a high-fat diet (w/w 21% fat) for 12 weeks. During the subsequent 12-week treatment period, the animals were allowed access to the high-fat diet and either water containing CAP (0.05 mg ml(-1)) or plain tap water (CON, control). RESULTS From the first week of treatment, food intake and body weight decreased in CAP-treated mice compared with CON mice. Both peripheral insulin sensitivity and hepatic insulin sensitivity were improved in CAP-treated mice compared with CON mice. CAP-treated mice had decreased absolute and relative liver and epididymal fat weights compared with CON mice. CAP-treated mice had higher plasma adiponectin and lower plasma leptin levels than CON mice. Relative to CON mice, CAP-treated mice had reduced adipose and skeletal muscle monocyte chemoattractant protein 1 (MCP-1), adipose interleukin-6 (IL-6), toll-like receptor 4 (TLR4) and uncoupling protein 2 (UCP2) mRNA expressions. Furthermore, CAP-treated mice had increased peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α), long chain acyl-CoA dehydrogenase (LCAD), hormone sensitive lipase (HSL) and decreased lipoprotein lipase (LPL) mRNA expressions in the liver. CONCLUSION The results of the current study indicate that in mice with DIO, CAP treatment reduced food intake and body weight, improved insulin sensitivity and decreased the mRNA expression of markers of inflammation. Thus, CAP may be a viable treatment for obesity, insulin resistance and inflammation.
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Affiliation(s)
- S D Premaratna
- School of Psychological Science, La Trobe University, Bundoora, Victoria, Australia
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31
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Yvan-Charvet L, Quignard-Boulangé A. Role of adipose tissue renin–angiotensin system in metabolic and inflammatory diseases associated with obesity. Kidney Int 2011; 79:162-8. [DOI: 10.1038/ki.2010.391] [Citation(s) in RCA: 150] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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de Kloet AD, Krause EG, Woods SC. The renin angiotensin system and the metabolic syndrome. Physiol Behav 2010; 100:525-34. [PMID: 20381510 DOI: 10.1016/j.physbeh.2010.03.018] [Citation(s) in RCA: 140] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2010] [Revised: 03/18/2010] [Accepted: 03/26/2010] [Indexed: 01/01/2023]
Abstract
The renin angiotensin system (RAS; most well-known for its critical roles in the regulation of cardiovascular function and hydromineral balance) has regained the spotlight for its potential roles in various aspects of the metabolic syndrome. It may serve as a causal link among obesity and several co-morbidities. Drugs that reduce the synthesis or action of angiotensin-II (A-II; the primary effector peptide of the RAS) have been used to treat hypertension for decades and, more recently, clinical trials have determined the utility of these pharmacological agents to prevent insulin resistance. Moreover, there is evidence that the RAS contributes to body weight regulation by acting in various tissues. This review summarizes what is known of the actions of the RAS in the brain and throughout the body to influence various metabolic disorders. Special emphasis is given to the role of the RAS in body weight regulation. The paper represents an invited review by a symposium, award winner or keynote speaker at the Society for the Study of Ingestive Behavior [SSIB] Annual Meeting in Portland, July 2009.
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Affiliation(s)
- Annette D de Kloet
- Program in Neuroscience University of Cincinnati, Cincinnati, OH 45237, United States.
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de Kloet AD, Krause EG, Kim DH, Sakai RR, Seeley RJ, Woods SC. The effect of angiotensin-converting enzyme inhibition using captopril on energy balance and glucose homeostasis. Endocrinology 2009; 150:4114-23. [PMID: 19497971 PMCID: PMC2736089 DOI: 10.1210/en.2009-0065] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Increasing evidence suggests that the renin-angiotensin-system contributes to the etiology of obesity. To evaluate the role of the renin-angiotensin-system in energy and glucose homeostasis, we examined body weight and composition, food intake, and glucose tolerance in rats given the angiotensin-converting enzyme inhibitor, captopril ( approximately 40 mg/kg . d). Rats given captopril weighed less than controls when fed a high-fat diet (369.3 +/- 8.0 vs. 441.7 +/- 8.5 g after 35 d; P < 0.001) or low-fat chow (320.1 +/- 4.9 vs. 339.8 +/- 5.1 g after 21 d; P < 0.0001). This difference was attributable to reductions in adipose mass gained on high-fat (23.8 +/- 2.0 vs. 65.12 +/- 8.4 g after 35 d; P < 0.0001) and low-fat diets (12.2 +/- 0.7 vs. 17.3 +/- 1.3 g after 21 d; P < 0.001). Rats given captopril ate significantly less [3110.3 +/- 57.8 vs. 3592.4 +/- 88.8 kcal (cumulative 35 d high fat diet intake); P < 0.001] despite increased in neuropeptide-Y mRNA expression in the arcuate nucleus of the hypothalamus and had improved glucose tolerance compared with free-fed controls. Comparisons with pair-fed controls indicated that decreases in diet-induced weight gain and adiposity and improved glucose tolerance were due, primarily, to decreased food intake. To determine whether captopril caused animals to defend a lower body weight, animals in both groups were fasted for 24 h and subsequently restricted to 20% of their intake for 2 d. When free food was returned, captopril and control rats returned to their respective body weights and elicited comparable hyperphagic responses. These results suggest that angiotensin-converting enzyme inhibition protects against the development of diet-induced obesity and glucose intolerance.
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Affiliation(s)
- Annette D de Kloet
- Program in Neuroscience, University of Cincinnati, Cincinnati, Ohio 45237, USA.
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34
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Hankinson AL. Epidemiologic and pathophysiologic links between obesity and hypertension. CURRENT CARDIOVASCULAR RISK REPORTS 2009. [DOI: 10.1007/s12170-009-0041-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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35
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Fowler SM, Kon V, Ma L, Richards WO, Fogo AB, Hunley TE. Obesity-related focal and segmental glomerulosclerosis: normalization of proteinuria in an adolescent after bariatric surgery. Pediatr Nephrol 2009; 24:851-5. [PMID: 18941798 DOI: 10.1007/s00467-008-1024-6] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/27/2008] [Revised: 09/15/2008] [Accepted: 09/17/2008] [Indexed: 12/11/2022]
Abstract
Obesity-related glomerulopathy (ORG) is a secondary form of focal and segmental glomerulosclerosis (FSGS) occurring in severely obese patients. A significant percentage of individuals with ORG will develop renal insufficiency or end stage renal disease. We report here a 17-year-old girl with morbid obesity (body mass index 56.8 kg/m(2)) and ORG presenting with nephrotic range proteinuria, who failed to improve following treatment with diet, exercise and angiotensin-converting enzyme inhibitor (ACEi)/angiotensin receptor blocker (ARB) therapy. Laparoscopic gastric bypass surgery was performed, and within 2 weeks following the surgery, the patient had lost 5.7 kg body weight and showed a remarkable decrease in protein excretion to one tenth of pre-surgery levels. More than 1 year after surgery, the patient's urine protein and kidney function have remained normal while off renin-angiotensin system inhibition therapy. This is the first report of successful use of gastric bypass surgery for obesity-related glomerulopathy in an adolescent. We propose that gastric bypass surgery be considered for patients with ORG.
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Affiliation(s)
- Susan M Fowler
- Division of Pediatric Nephrology, Monroe Carell Jr. Children's Hospital at Vanderbilt, 11133 Doctors' Office Tower, 2200 Children's Way, Nashville, TN 37232-9560, USA
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Galletti F, Strazzullo P. Involvement of the renin-angiotensin system in obesity: older and newer pathways. Nutr Metab Cardiovasc Dis 2007; 17:699-704. [PMID: 17698332 DOI: 10.1016/j.numecd.2007.03.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/18/2007] [Accepted: 03/07/2007] [Indexed: 10/23/2022]
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Abstract
The renin-angiotensin-aldosterone system (RAAS) is a key regulator of cardiovascular function. RAAS activity is upregulated in obesity despite concurrent renal sodium retention, which is a hallmark and principle determinant of obesity-associated hypertension. The contribution of adipose tissue to increased angiotensinogen and aldosterone plasma levels in obesity is probably due to the secretion of angiotensinogen and, as yet, unidentified aldosterone secretagogues by adipocytes. Increased circulating renin activity, on the other hand, is probably due to increased sympathetic activity in the obese. Modest weight reduction significantly reduces RAAS activity by uncertain mechanisms. Pharmacological blockade of the RAAS yielded promising results, both with regard to cardiovascular function and metabolic complications of obesity. These studies suggest that the activated RAAS is a prime pharmacological target for reducing the cardiometabolic risk in obese patients.
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Affiliation(s)
- Arya M Sharma
- b Professor of Medicine, Canada Research Chair for Cardiovascular Obesity Research and Management, McMaster University, Hamilton General Hospital, 237 Barton Street East, Hamilton, ON, Canada L8L 2X2 .
| | - Stefan Engeli
- a Franz-Volhard-Zentrum für Klinische Forschung (Haus 129), Charité Campus Buch, Wiltbergstr. 50, 13125 Berlin, Germany.
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Lamounier-Zepter V, Ehrhart-Bornstein M, Bornstein SR. Mineralocorticoid-stimulating activity of adipose tissue. Best Pract Res Clin Endocrinol Metab 2005; 19:567-75. [PMID: 16311217 DOI: 10.1016/j.beem.2005.07.002] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Obesity is strongly associated with arterial hypertension. A positive correlation between obesity and plasma aldosterone levels has been observed by different investigators, suggesting that an abnormal secretion of aldosterone in obesity contributes to the development of arterial hypertension in obese subjects. The mechanisms proposed to explain this abnormal aldosterone production mainly involve the adipose renin-angiotensin system, an indirect effect of increased fatty acids, and direct adrenal stimulation by adipocyte secretory products. Indeed, adipose mineralocorticoid-stimulating activity was recently observed in isolated human adipocytes, suggesting a hitherto unknown direct involvement of adipose tissue in the regulation of blood pressure in obesity.
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Affiliation(s)
- Valeria Lamounier-Zepter
- Department of Endocrinology, Diabetes and Metabolism, University Medical Centre, University of Dresden, Germany
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Li Y, Jain S, Patil S, Kumar A. A haplotype of angiotensinogen gene that is associated with essential hypertension increases its promoter activity in adipocytes. Vascul Pharmacol 2005; 44:29-33. [PMID: 16303336 DOI: 10.1016/j.vph.2005.09.009] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2005] [Revised: 09/01/2005] [Accepted: 09/10/2005] [Indexed: 10/25/2022]
Abstract
Obesity is associated with hypertension and other cardiovascular diseases especially in the African-American population. Human angiotensinogen (AGT) gene has seven single nucleotide polymorphisms (SNPs) in 1.2 kb region of its promoter. Recent studies have shown that variant -217A is associated with hypertension in African-American and Chinese population. Nucleotide sequence of the hAGT gene has shown that variant -217A almost always occurs with variants -532T, -793A and -1074T (forming haplotype AAT) and variant -217G almost always occurs with variants -532C, -793G and -1074G (forming haplotype GGG). Since hAGT gene is expressed in the adipose tissue and its expression in this tissue may play a role in hypertension, we have analyzed the role of haplotypes AAT and GGG on the expression of this gene in adipocytes. We show here that a reporter construct with haplotype AAT of the hAGT gene has increased promoter activity on transient transfection in pre-adipocytes and differentiated adipocytes as compared to the reporter construct containing GCGG haplotype. Increased expression of the AGT gene containing haplotype AAT in the liver and adipocytes may be a contributing factor for hypertension.
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Affiliation(s)
- Yanna Li
- Department of Pathology, New York Medical College, Valhalla, NY 10595, United States
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Crowley SD, Gurley SB, Oliverio MI, Pazmino AK, Griffiths R, Flannery PJ, Spurney RF, Kim HS, Smithies O, Le TH, Coffman TM. Is the Kidney Always the Cause of Hypertension? J Am Soc Nephrol 2005. [DOI: 10.1681/asn.2005040379] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
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Boustany CM, Brown DR, Randall DC, Cassis LA. AT1-receptor antagonism reverses the blood pressure elevation associated with diet-induced obesity. Am J Physiol Regul Integr Comp Physiol 2005; 289:R181-6. [PMID: 15774768 DOI: 10.1152/ajpregu.00507.2004] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Previous studies in our laboratory demonstrated that rats exhibiting obesity in response to a moderately high-fat (MHF) diet developed hypertension associated with activation of the local and systemic renin-angiotensin system. In this study, we examined the effect of the angiotensin type 1 (AT(1))-receptor antagonist, losartan, on blood pressure in obesity-prone (OP) and obesity-resistant (OR) rats fed a MHF diet. Using telemetry monitoring, we characterized the evolution of blood pressure elevations during the development of obesity. Male Sprague-Dawley rats were implanted with telemetry transducers for chronic monitoring of blood pressure, and baseline measurements were obtained. Rats were then switched to the MHF diet (32% kcal as fat) and were segregated into OP and OR groups at week 5. At week 9 on the MHF diet, OP rats exhibited significantly greater 24-h mean arterial blood pressure compared with OR rats (OP: 105 +/- 4 mmHg, OR: 96 +/- 2 mmHg; P < 0.05). Elevations in blood pressure in OP rats were manifest as an increase in systolic pressure. Administration of losartan to all rats at week 9 resulted in a reduction in blood pressure; however, losartan had the greatest effect in OP rats (percent decrease in mean arterial pressure by losartan; OP: 19 +/- 4, OR: 10 +/- 2%; P < 0.05). These results demonstrate that elevations in blood pressure occur subsequent to established obesity in rats fed a high-fat diet. Moreover, these results demonstrate the ability of losartan to reverse the blood pressure increase from diet-induced obesity, supporting a primary role for the renin-angiotensin system in obesity-associated hypertension.
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Affiliation(s)
- Carine M Boustany
- Division of Pharmaceutical Sciences, University of Kentucky, Lexington, KY 40536-0200, USA
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Fejerman L, Bouzekri N, Wu X, Adeyemo A, Luke A, Zhu X, Ward R, Cooper RS. Association between evolutionary history of angiotensinogen haplotypes and plasma levels. Hum Genet 2005; 115:310-8. [PMID: 15278435 DOI: 10.1007/s00439-004-1141-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Over the last decade, considerable effort has been invested in studying the associations between angiotensinogen (AGT) variants, AGT plasma levels and high blood pressure. Evidence accumulated to date consistently supports the relationship between the AGT locus and the protein level, while an influence on blood pressure has been difficult to establish; in both instances the predisposing molecular variants are not fully defined. An evolutionary approach, taking into account the phylogenetic relationship between all the polymorphisms at this locus, may improve our understanding of the genetic nature of these quantitative phenotypes. Accordingly we sequenced a 6.8 kb region of the AGT gene in 57 Nigerian individuals (29 with high AGT plasma levels and 28 with low AGT plasma levels). Haplotypes were grouped into seven major haplogroups and their phylogenetic relationship was established. The association between haplogroups and AGT plasma levels was investigated. A significant linear correlation was detected between haplogroup genetic distance and AGT levels, suggesting a nonrandom accumulation of risk-associated mutations during the evolutionary history of the AGT gene.
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Affiliation(s)
- Laura Fejerman
- Department of Biological Anthropology, Oxford University, Oxford, UK
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Engeli S, Böhnke J, Gorzelniak K, Janke J, Schling P, Bader M, Luft FC, Sharma AM. Weight loss and the renin-angiotensin-aldosterone system. Hypertension 2005; 45:356-62. [PMID: 15630041 DOI: 10.1161/01.hyp.0000154361.47683.d3] [Citation(s) in RCA: 442] [Impact Index Per Article: 23.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The renin-angiotensin-aldosterone system has been causally implicated in obesity-associated hypertension. We studied the influence of obesity and weight reduction on the circulating and adipose tissue renin-angiotensin-aldosterone system in menopausal women. Blood samples were analyzed for angiotensinogen, renin, aldosterone, angiotensin-converting enzyme activity, and angiotensin II. In adipose tissue biopsy samples, we analyzed angiotensinogen, renin, renin-receptor, angiotensin-converting enzyme, and angiotensin II type-1 receptor gene expression. Obese women (n=19) had higher circulating angiotensinogen, renin, aldosterone, and angiotensin-converting enzyme than lean women (n=19), and lower angiotensinogen gene expression in adipose tissue. Seventeen women successfully participated in a weight reduction protocol over 13 weeks to reduce daily caloric intake by 600 kcal. Body weight was reduced by -5%, as were angiotensinogen levels by -27%, renin by -43%, aldosterone by -31%, angiotensin-converting enzyme activity by -12%, and angiotensinogen expression by -20% in adipose tissue (all P<0.05). The plasma angiotensinogen decrease was highly correlated with the waist circumference decline (r=0.74; P<0.001). Weight and renin-angiotensin-aldosterone system reductions were accompanied by a -7-mm Hg reduced systolic ambulatory blood pressure. These data suggest that a 5% reduction in body weight can lead to a meaningfully reduced renin-angiotensin-aldosterone system in plasma and adipose tissue, which may contribute to the reduced blood pressure.
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Affiliation(s)
- Stefan Engeli
- Medical Faculty of the Charité, Franz Volhard Clinic and Max Delbrück Center for Molecular Medicine, HELIOS-Klinikum, Berlin, Germany.
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Serazin V, Dos Santos E, Morot M, Giudicelli Y. Human adipose angiotensinogen gene expression and secretion are stimulated by cyclic AMP via increased DNA cyclic AMP responsive element binding activity. Endocrine 2004; 25:97-104. [PMID: 15711021 DOI: 10.1385/endo:25:2:097] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/15/2004] [Revised: 09/29/2004] [Accepted: 10/11/2004] [Indexed: 11/11/2022]
Abstract
Components of the adipose renin-angiotensin system (RAS) have been suggested as providing a potential path-way linking obesity to hypertension. In adipose cells, the biological responses to beta-adrenergic stimulation are mediated by an increase in intracellular cAMP. Because an association exists among body fat mass, hypertension, and increased sympathetic stimulation, we examined the influence of cAMP on angiotensinogen (ATG) expression and secretion in human adipose tissue and in parallel we studied the DNA binding activity of CRE transcriptional factors. A 24 h exposure to the cAMP analog 8Br-cAMP resulted in significant increases in ATG mRNA levels (+176+/-60%) and protein secretion (+40+/-27%). The ability of 8Br-cAMP to promote ATG gene expression was unaltered by H89, a protein kinase A inhibitor, because H89 per se was found to stimulate ATG mRNA levels and protein secretion. Moreover, 8Br-cAMP stimulated the specific CRE DNA binding activity (+115+/-14%) in human adipocyte nuclear extracts as assessed by electrophoretic mobility shift assays. These results indicate that cAMP upregulates in vitro ATG expression and secretion in human adipose tissue and that the induction in ATG mRNA levels appears to result, at least in part, from positive effects on the DNA binding activity of CRE transcription factors. Further studies are required to determine whether this regulatory pathway is activated in human obesity and to elucidate the importance of adipose ATG to the elevated blood pressure observed in this pathological state.
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Affiliation(s)
- Valérie Serazin
- Laboratoire de Biochimie et de Biologie Moléculaire de la Faculté de Médecine Paris-Ile-de-France-Ouest, UPRES EA 2493, Université Versailles Saint Quentin en Yvelines, and Hôpital de Poissy, F78303 Poissy Cedex France
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Prat-Larquemin L, Oppert JM, Clément K, Hainault I, Basdevant A, Guy-Grand B, Quignard-Boulangé A. Adipose angiotensinogen secretion, blood pressure, and AGT M235T polymorphism in obese patients. ACTA ACUST UNITED AC 2004; 12:556-61. [PMID: 15044674 DOI: 10.1038/oby.2004.63] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
OBJECTIVE To investigate AGT secretion in cultured adipocytes from obese patients and its relationship with obesity-related phenotypes, blood pressure, and the M235T polymorphism in the AGT gene. RESEARCH METHODS AND PROCEDURES Measurements, including anthropometry, body composition (DXA), and blood pressure, were performed in 61 overweight or obese women (BMI: 28 to 68 kg/m(2)). A subcutaneous abdominal adipose tissue biopsy was used for adipocyte size determination and quantification of AGT secretion in the medium of cultured adipocytes. AGT M235T genotype was determined using polymerase chain reaction-restriction fragment length polymorphism. RESULTS Adipose secretion of the AGT protein (range, 140 to 2575 ng/10(6) cells/24 h) was not significantly correlated with BMI, body fat, or blood pressure and did not vary according to the M235T polymorphism in the AGT gene. However, the AGT M235T polymorphism was associated with adipocyte size (111.6 +/- 2.8, 108.8 +/- 1.9, 118.2 +/- 2.6 micro m in MM, MT, and TT genotypes, respectively; p < 0.01) after adjustment for age and fat mass. An association between the AGT M235T polymorphism and adipocyte size (p < 0.02 adjusted for sex, age, and BMI) was found in another independent sample of 106 obese subjects (sex ratio, M/F 16/90; BMI, 29 to 70 kg/m(2)). DISCUSSION In cultured adipocytes from obese subjects, AGT secretion was not associated with body fat phenotypes, blood pressure, or fat cell size. However, results from two independent studies suggest an association between the AGT M235T polymorphism and adipocyte size.
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Rahmouni K, Mark AL, Haynes WG, Sigmund CD. Adipose depot-specific modulation of angiotensinogen gene expression in diet-induced obesity. Am J Physiol Endocrinol Metab 2004; 286:E891-5. [PMID: 14749209 DOI: 10.1152/ajpendo.00551.2003] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Adipose tissue represents an important source of angiotensinogen (AGT). We investigated the effect of obesity induced by a high-fat diet on the expression of mouse (mAGT) and human AGT (hAGT) genes in liver, kidney, and heart and different adipose depots in normal mice (C57BL/6J), and in transgenic mice expressing the hAGT gene under the control of its own promoter. Mice were fed a high-fat diet (45% kcal) or normal chow (10% kcal) for 10 and 20 wk. The expression of mAGT and hAGT mRNA was quantified using an RNAse protection assay. Mice on the high-fat diet exhibited increased weight, fat mass, and plasma leptin. Expression of mAGT or hAGT genes was not affected by high-fat diet in nonadipose tissues, brown adipose tissue, or subcutaneous white fat. In contrast, high-fat diet increased both mAGT and hAGT gene expression in visceral adipose depots (omental, reproductive, and perirenal fat). Thus obesity-induced by a high-fat diet is associated with a tissue-specific increased expression of both mouse and human AGT genes in intra-abdominal adipose tissue. Our findings also suggest that 1.2 kb of regulatory sequences present in the hAGT transgene are sufficient to transcriptionally respond to a high-fat diet in an adipose-specific and depot-specific manner.
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Affiliation(s)
- Kamal Rahmouni
- Hypertension Genetics Specialized Center of Research, Cardiovascular Center, Department of Internal Medical, University of Iowa Carver College of Medicine, Iowa City 52242, USA
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Abstract
This article has discussed some of the mechanisms involved in the causal relation between obesity and hypertension. Obesity causes a constellation of maladaptive disorders that individually and synergistically contribute to hypertension, among other cardiovascular morbidities. Well-designed population-based studies are needed to assess the individual contribution of each of these disorders to the development of hypertension. In addition, because the control of obesity may eliminate 48% of the hypertension in whites and 28% in blacks, this article has offered an up-to-date on the management of this problem. It is hoped that this article will help scientists formulate a thorough understanding of obesity hypertension and form the basis for more research in this field, which has a huge impact on human life.
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Affiliation(s)
- Fadi El-Atat
- Division of Cardiovascular Diseases, Department of Medicine, State University of New York Health Science Center and Veteran Affairs Hospital, 450 Clarkson Avenue, Brooklyn, NY 11201, USA
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Castro JP, El-Atat FA, McFarlane SI, Aneja A, Sowers JR. Cardiometabolic syndrome: pathophysiology and treatment. Curr Hypertens Rep 2003; 5:393-401. [PMID: 12948432 DOI: 10.1007/s11906-003-0085-y] [Citation(s) in RCA: 98] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The cardiometabolic syndrome, an interesting constellation of maladaptive cardiovascular, renal, metabolic, prothrombotic, and inflammatory abnormalities, is now recognized as a disease entity by the American Society of Endocrinology, National Cholesterol Education Program, and World Health Organization, among others. These cardiovascular and metabolic derangements individually and interdependently lead to a substantial increase in cardiovascular disease (CVD) morbidity and mortality, making the cardiometabolic syndrome an established and strong risk factor for premature and severe CVD and stroke. Established and evolving treatment strategies including moderate physical activity, weight reduction, rigorous blood pressure control, correction of dyslipidemia, and glycemic control have proven beneficial in reversing these abnormal responses and decreasing the CVD risk.
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Affiliation(s)
- Jonathan P Castro
- Division of Endocrinology, Diabetes and Hypertension, State University of New York Downstate and Brooklyn Veterans Affairs Medical Center, Brooklyn, NY 11203, USA.
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Gates PE, Gentile CL, Seals DR, Christou DD. Adiposity contributes to differences in left ventricular structure and diastolic function with age in healthy men. J Clin Endocrinol Metab 2003; 88:4884-90. [PMID: 14557469 DOI: 10.1210/jc.2003-030673] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
We sought to examine the influence of adiposity in age-associated changes in the left ventricle (LV) in a cohort of 113 healthy men, aged 20-79 yr, by measuring LV structure and diastolic function (echocardiography), whole body composition, and regional adiposity (dual energy x-ray absorptiometry). Aging was associated with increased levels of adiposity, greater wall thickness to chamber radius ratio, LV concentric remodeling, and reduced LV diastolic function (all P < 0.05). Bivariate correlation analysis showed that mean LV wall thickness, a concentric LV morphology, and diastolic function were related to adiposity (r = -0.63 to 0.51; all P < 0.05). The relation between age and both mean LV wall thickness and concentric remodeling was reduced after controlling for percentage total body fat (by 38% and 54%, respectively), percentage abdominal fat (by 42% and 62%), and the abdominal/thigh fat ratio (by 35% and 46%). The diastolic function-age relation was reduced after controlling for percentage total body fat (by 35%), percentage abdominal fat (by 39%), and the abdominal/thigh fat ratio (by 29%). There were no apparent differences in the contribution of percentage total body fat, percentage abdominal fat, or abdominal/thigh fat to the association between age and LV structure/diastolic function. We conclude that increasing adiposity contributes to the LV remodeling/reduced diastolic function that occurs with aging in healthy men.
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Affiliation(s)
- Phillip E Gates
- Department of Integrative Physiology, University of Colorado, Boulder, Colorado 80309, USA.
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Goossens GH, Blaak EE, van Baak MA. Possible involvement of the adipose tissue renin-angiotensin system in the pathophysiology of obesity and obesity-related disorders. Obes Rev 2003; 4:43-55. [PMID: 12608526 DOI: 10.1046/j.1467-789x.2003.00091.x] [Citation(s) in RCA: 132] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Angiotensin II (Ang II), acting on the AT1 and AT2 receptors in mammalian cells, is the vasoactive component of the renin-angiotensin system (RAS). Several components of the RAS have been demonstrated in different tissues, including adipose tissue. Although the effects of Ang II on metabolism have not been studied widely, it is intriguing to assume that components of the RAS produced by adipocytes may play an autocrine, a paracrine and/or an endocrine role in the pathophysiology of obesity and provide a potential pathway through which obesity leads to hypertension and type 2 diabetes mellitus. In the first part of this review, we will describe the production of Ang II, the different receptors through which Ang II exerts its effects and summarize the concomitant intracellular signalling cascades. Thereafter, potential Ang II-induced mechanisms, which may be associated with obesity and obesity-related disorders, will be considered. Finally, we will focus on the different pharmaceutical agents that interfere with the RAS and highlight the possible implications of these drugs in the treatment of obesity-related disorders.
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Affiliation(s)
- G H Goossens
- Department of Human Biology, Nutrition and Toxicology Research Institute Maastricht, Maastricht University, Maastricht, The Netherlands.
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