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Gluvic Z, Obradovic M, Manojlovic M, Vincenza Giglio R, Maria Patti A, Ciaccio M, Suri JS, Rizzo M, Isenovic ER. Impact of different hormones on the regulation of nitric oxide in diabetes. Mol Cell Endocrinol 2024; 592:112325. [PMID: 38968968 DOI: 10.1016/j.mce.2024.112325] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/03/2024] [Revised: 06/10/2024] [Accepted: 07/02/2024] [Indexed: 07/07/2024]
Abstract
Polymetabolic syndrome achieved pandemic proportions and dramatically influenced public health systems functioning worldwide. Chronic vascular complications are the major contributors to increased morbidity, disability, and mortality rates in diabetes patients. Nitric oxide (NO) is among the most important vascular bed function regulators. However, NO homeostasis is significantly deranged in pathological conditions. Additionally, different hormones directly or indirectly affect NO production and activity and subsequently act on vascular physiology. In this paper, we summarize the recent literature data related to the effects of insulin, estradiol, insulin-like growth factor-1, ghrelin, angiotensin II and irisin on the NO regulation in physiological and diabetes circumstances.
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Affiliation(s)
- Zoran Gluvic
- University Clinical-Hospital Centre Zemun-Belgrade, Clinic of Internal Medicine, Department of Endocrinology and Diabetes, Faculty of Medicine, University of Belgrade, Belgrade, Serbia.
| | - Milan Obradovic
- Department of Radiobiology and Molecular Genetics, VINČA Institute of Nuclear Sciences - National Institute of the Republic of Serbia, University of Belgrade, Belgrade, Serbia
| | - Mia Manojlovic
- Faculty of Medicine Novi Sad, University of Novi Sad, Novi Sad, Serbia; Clinic for Endocrinology, Diabetes and Metabolic Disorders, Clinical Center of Vojvodina, Novi Sad, Serbia
| | - Rosaria Vincenza Giglio
- Department of Biomedicine, Neuroscience and Advanced Diagnostics, University of Palermo, Italy; Department of Laboratory Medicine, University Hospital, Palermo, Italy
| | - Angelo Maria Patti
- Department of Health Promotion Sciences Maternal and Infantile Care, Internal Medicine and Medical Specialties, University of Palermo, Italy
| | - Marcello Ciaccio
- Department of Biomedicine, Neuroscience and Advanced Diagnostics, University of Palermo, Italy; Department of Laboratory Medicine, University Hospital, Palermo, Italy
| | - Jasjit S Suri
- Stroke Monitoring and Diagnostic Division, AtheroPoint™, Roseville, CA, 95661, USA
| | - Manfredi Rizzo
- Internal Medicine Unit, "Vittorio Emanuele II" Hospital, Castelvetrano, Italy
| | - Esma R Isenovic
- Department of Radiobiology and Molecular Genetics, VINČA Institute of Nuclear Sciences - National Institute of the Republic of Serbia, University of Belgrade, Belgrade, Serbia
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Macvanin M, Gluvic Z, Radovanovic J, Essack M, Gao X, Isenovic ER. New insights on the cardiovascular effects of IGF-1. Front Endocrinol (Lausanne) 2023; 14:1142644. [PMID: 36843588 PMCID: PMC9947133 DOI: 10.3389/fendo.2023.1142644] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Accepted: 01/26/2023] [Indexed: 02/11/2023] Open
Abstract
INTRODUCTION Cardiovascular (CV) disorders are steadily increasing, making them the world's most prevalent health issue. New research highlights the importance of insulin-like growth factor 1 (IGF-1) for maintaining CV health. METHODS We searched PubMed and MEDLINE for English and non-English articles with English abstracts published between 1957 (when the first report on IGF-1 identification was published) and 2022. The top search terms were: IGF-1, cardiovascular disease, IGF-1 receptors, IGF-1 and microRNAs, therapeutic interventions with IGF-1, IGF-1 and diabetes, IGF-1 and cardiovascular disease. The search retrieved original peer-reviewed articles, which were further analyzed, focusing on the role of IGF-1 in pathophysiological conditions. We specifically focused on including the most recent findings published in the past five years. RESULTS IGF-1, an anabolic growth factor, regulates cell division, proliferation, and survival. In addition to its well-known growth-promoting and metabolic effects, there is mounting evidence that IGF-1 plays a specialized role in the complex activities that underpin CV function. IGF-1 promotes cardiac development and improves cardiac output, stroke volume, contractility, and ejection fraction. Furthermore, IGF-1 mediates many growth hormones (GH) actions. IGF-1 stimulates contractility and tissue remodeling in humans to improve heart function after myocardial infarction. IGF-1 also improves the lipid profile, lowers insulin levels, increases insulin sensitivity, and promotes glucose metabolism. These findings point to the intriguing medicinal potential of IGF-1. Human studies associate low serum levels of free or total IGF-1 with an increased risk of CV and cerebrovascular illness. Extensive human trials are being conducted to investigate the therapeutic efficacy and outcomes of IGF-1-related therapy. DISCUSSION We anticipate the development of novel IGF-1-related therapy with minimal side effects. This review discusses recent findings on the role of IGF-1 in the cardiovascular (CVD) system, including both normal and pathological conditions. We also discuss progress in therapeutic interventions aimed at targeting the IGF axis and provide insights into the epigenetic regulation of IGF-1 mediated by microRNAs.
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Affiliation(s)
- Mirjana Macvanin
- Department of Radiobiology and Molecular Genetics, VINČA Institute of Nuclear Sciences - National Institute of the Republic of Serbia, University of Belgrade, Belgrade, Serbia
- *Correspondence: Mirjana Macvanin,
| | - Zoran Gluvic
- Clinic for Internal Medicine, Department of Endocrinology and Diabetes, Zemun Clinical Hospital, School of Medicine, University of Belgrade, Belgrade, Serbia
| | - Jelena Radovanovic
- Department of Radiobiology and Molecular Genetics, VINČA Institute of Nuclear Sciences - National Institute of the Republic of Serbia, University of Belgrade, Belgrade, Serbia
| | - Magbubah Essack
- Computational Bioscience Research Center (CBRC), King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
- Computer Science Program, Computer, Electrical and Mathematical Sciences and Engineering Division (CEMSE), King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Xin Gao
- Computational Bioscience Research Center (CBRC), King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
- Computer Science Program, Computer, Electrical and Mathematical Sciences and Engineering Division (CEMSE), King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Esma R. Isenovic
- Department of Radiobiology and Molecular Genetics, VINČA Institute of Nuclear Sciences - National Institute of the Republic of Serbia, University of Belgrade, Belgrade, Serbia
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Gluvic ZM, Obradovic MM, Sudar-Milovanovic EM, Zafirovic SS, Radak DJ, Essack MM, Bajic VB, Takashi G, Isenovic ER. Regulation of nitric oxide production in hypothyroidism. Biomed Pharmacother 2020; 124:109881. [PMID: 31986413 DOI: 10.1016/j.biopha.2020.109881] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Revised: 12/25/2019] [Accepted: 01/06/2020] [Indexed: 02/08/2023] Open
Abstract
Hypothyroidism is a common endocrine disorder that predominantly occurs in females. It is associated with an increased risk of cardiovascular diseases (CVD), but the molecular mechanism is not known. Disturbance in lipid metabolism, the regulation of oxidative stress, and inflammation characterize the progression of subclinical hypothyroidism. The initiation and progression of endothelial dysfunction also exhibit these changes, which is the initial step in developing CVD. Animal and human studies highlight the critical role of nitric oxide (NO) as a reliable biomarker for cardiovascular risk in subclinical and clinical hypothyroidism. In this review, we summarize the recent literature findings associated with NO production by the thyroid hormones in both physiological and pathophysiological conditions. We also discuss the levothyroxine treatment effect on serum NO levels in hypothyroid patients.
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Affiliation(s)
- Zoran M Gluvic
- Zemun Clinical Hospital, School of Medicine, University of Belgrade, Belgrade, Serbia; School of Medicine, University of Belgrade, Belgrade, Serbia.
| | - Milan M Obradovic
- Vinca Institute of Nuclear Sciences, University of Belgrade, Laboratory of Radiobiology and Molecular Genetics, Belgrade, Serbia.
| | - Emina M Sudar-Milovanovic
- Vinca Institute of Nuclear Sciences, University of Belgrade, Laboratory of Radiobiology and Molecular Genetics, Belgrade, Serbia.
| | - Sonja S Zafirovic
- Vinca Institute of Nuclear Sciences, University of Belgrade, Laboratory of Radiobiology and Molecular Genetics, Belgrade, Serbia.
| | | | - Magbubah M Essack
- King Abdullah University of Science and Technology (KAUST), Computational Bioscience Research Center (CBRC), Computer, Electrical and Mathematical Sciences and Engineering (CEMSE) Division, Thuwal, Saudi Arabia.
| | - Vladimir B Bajic
- King Abdullah University of Science and Technology (KAUST), Computational Bioscience Research Center (CBRC), Computer, Electrical and Mathematical Sciences and Engineering (CEMSE) Division, Thuwal, Saudi Arabia.
| | - Gojobori Takashi
- King Abdullah University of Science and Technology (KAUST), Computational Bioscience Research Center (CBRC), Computer, Electrical and Mathematical Sciences and Engineering (CEMSE) Division, Thuwal, Saudi Arabia; King Abdullah University of Science and Technology (KAUST), Biological and Environmental Sciences and Engineering Division (BESE), Thuwal 23955-6900, Saudi Arabia.
| | - Esma R Isenovic
- Vinca Institute of Nuclear Sciences, University of Belgrade, Laboratory of Radiobiology and Molecular Genetics, Belgrade, Serbia.
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Obradovic M, Zafirovic S, Soskic S, Stanimirovic J, Trpkovic A, Jevremovic D, Isenovic ER. Effects of IGF-1 on the Cardiovascular System. Curr Pharm Des 2019; 25:3715-3725. [DOI: 10.2174/1381612825666191106091507] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Accepted: 10/29/2019] [Indexed: 11/22/2022]
Abstract
:Cardiovascular (CV) diseases are the most common health problems worldwide, with a permanent increase in incidence. Growing evidence underlines that insulin-like growth factor 1 (IGF-1) is a very important hormone responsible for normal CV system physiology. IGF-1 is an anabolic growth hormone, responsible for cell growth, differentiation, proliferation, and survival. Despite systemic effects, IGF-1 exerts a wide array of influences in the CV system affecting metabolic homeostasis, vasorelaxation, cardiac contractility and hypertrophy, autophagy, apoptosis, and antioxidative processes. The vasodilatory effect of IGF-1, is achieved through the regulation of the activity of endothelial nitric oxide synthase (eNOS) and, at least partly, through enhancing inducible NOS (iNOS) activity. Also, IGF-1 stimulates vascular relaxation through regulation of sodium/potassiumadenosine- triphosphatase. Numerous animal studies provided evidence of diverse influences of IGF-1 in the CV system such as vasorelaxation, anti-apoptotic and prosurvival effects. Human studies indicate that low serum levels of free or total IGF-1 contribute to an increased risk of CV and cerebrovascular disease. Large human trials aiming at finding clinical efficacy and outcome of IGF-1-related therapy are of great interest.:We look forward to the development of new IGF 1 therapies with minor side effects. In this review, we discuss the latest literature data regarding the function of IGF-1 in the CV system in the physiological and pathophysiological conditions.
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Affiliation(s)
- Milan Obradovic
- Laboratory of Radiobiology and Molecular Genetics, Vinca Institute of Nuclear Sciences, University of Belgrade, Mike Petrovica Alasa 12-14, 11000 Belgrade, Serbia
| | - Sonja Zafirovic
- Laboratory of Radiobiology and Molecular Genetics, Vinca Institute of Nuclear Sciences, University of Belgrade, Mike Petrovica Alasa 12-14, 11000 Belgrade, Serbia
| | - Sanja Soskic
- Laboratory of Radiobiology and Molecular Genetics, Vinca Institute of Nuclear Sciences, University of Belgrade, Mike Petrovica Alasa 12-14, 11000 Belgrade, Serbia
| | - Julijana Stanimirovic
- Laboratory of Radiobiology and Molecular Genetics, Vinca Institute of Nuclear Sciences, University of Belgrade, Mike Petrovica Alasa 12-14, 11000 Belgrade, Serbia
| | - Andreja Trpkovic
- Laboratory of Radiobiology and Molecular Genetics, Vinca Institute of Nuclear Sciences, University of Belgrade, Mike Petrovica Alasa 12-14, 11000 Belgrade, Serbia
| | - Danimir Jevremovic
- Faculty of Stomatology, Pancevo, University Business Academy, 21000 Novi Sad, Serbia
| | - Esma R. Isenovic
- Laboratory of Radiobiology and Molecular Genetics, Vinca Institute of Nuclear Sciences, University of Belgrade, Mike Petrovica Alasa 12-14, 11000 Belgrade, Serbia
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Badran A, Baydoun E, Samaha A, Pintus G, Mesmar J, Iratni R, Issa K, Eid AH. Marjoram Relaxes Rat Thoracic Aorta Via a PI3-K/eNOS/cGMP Pathway. Biomolecules 2019; 9:biom9060227. [PMID: 31212721 PMCID: PMC6627793 DOI: 10.3390/biom9060227] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Revised: 05/28/2019] [Accepted: 05/29/2019] [Indexed: 12/28/2022] Open
Abstract
Despite pharmacotherapeutic advances, cardiovascular disease (CVD) remains the primary cause of global mortality. Alternative approaches, such as herbal medicine, continue to be sought to reduce this burden. Origanum majorana is recognized for many medicinal values, yet its vasculoprotective effects remain poorly investigated. Here, we subjected rat thoracic aortae to increasing doses of an ethanolic extract of Origanum majorana (OME). OME induced relaxation in a dose-dependent manner in endothelium-intact rings. This relaxation was significantly blunted in denuded rings. N(ω)-nitro-l-arginine methyl ester (L-NAME) or 1H-[1,2,4]oxadiazolo[4,3,-a]quinoxalin-1-one (ODQ) significantly reduced the OME-induced vasorelaxation. Cyclic guanosine monophosphate (cGMP) levels were also increased by OME. Moreover, wortmannin or LY294002 significantly reduced OME-induced vasorelaxation. Blockers of ATP-sensitive or Ca2+-activated potassium channels such as glibenclamide or tetraethylamonium (TEA), respectively, did not significantly affect OME-induced relaxation. Similarly, verapamil, a Ca2+ channel blocker, indomethacin, a non-selective cyclooxygenase inhibitor, and pyrilamine, a H1 histamine receptor blocker, did not significantly modulate the observed relaxation. Taken together, our results show that OME induces vasorelaxation via an endothelium-dependent mechanism involving the phosphoinositide 3-kinase (PI3-K)/ endothelial nitric oxide (NO) synthase (eNOS)/cGMP pathway. Our findings further support the medicinal value of marjoram and provide a basis for its beneficial intake. Although consuming marjoram may have an antihypertensive effect, further studies are needed to better determine its effects in different vascular beds.
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Affiliation(s)
- Adnan Badran
- Department of Nutrition, University of Petra, Amman, P.O. Box 961343 Amman 11196, Jordan.
| | - Elias Baydoun
- Department of Biology, American University of Beirut, Beirut, P.O. Box 11-0236, Lebanon.
| | - Ali Samaha
- Department of Biomedical Sciences, Lebanese International University, Beirut, P.O. Box: 146404 Mazraa, Lebanon.
- Faculty of Public Health IV, Lebanese University, Beirut, P.O. Box 6573/14 Badaro, Lebanon.
| | - Gianfranco Pintus
- Department of Biomedical Sciences, Qatar University, Doha, P.O. Box 2713, Qatar.
- Biomedical Research Center, Qatar University, Doha, P.O. Box 2713, Qatar.
| | - Joelle Mesmar
- Department of Biology, American University of Beirut, Beirut, P.O. Box 11-0236, Lebanon.
| | - Rabah Iratni
- Department of Biology, United Arab Emirates University, Al Ain, P.O. Box 15551, United Arab Emirates.
| | - Khodr Issa
- Department of Pharmacology and Toxicology, American University of Beirut, Beirut, P.O. Box 11-0236, Lebanon.
| | - Ali H Eid
- Department of Pharmacology and Toxicology, American University of Beirut, Beirut, P.O. Box 11-0236, Lebanon.
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Sivasubramaniyam T, Schroer SA, Li A, Luk CT, Shi SY, Besla R, Dodington DW, Metherel AH, Kitson AP, Brunt JJ, Lopes J, Wagner KU, Bazinet RP, Bendeck MP, Robbins CS, Woo M. Hepatic JAK2 protects against atherosclerosis through circulating IGF-1. JCI Insight 2017; 2:93735. [PMID: 28724798 DOI: 10.1172/jci.insight.93735] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2017] [Accepted: 06/06/2017] [Indexed: 01/12/2023] Open
Abstract
Atherosclerosis is considered both a metabolic and inflammatory disease; however, the specific tissue and signaling molecules that instigate and propagate this disease remain unclear. The liver is a central site of inflammation and lipid metabolism that is critical for atherosclerosis, and JAK2 is a key mediator of inflammation and, more recently, of hepatic lipid metabolism. However, precise effects of hepatic Jak2 on atherosclerosis remain unknown. We show here that hepatic Jak2 deficiency in atherosclerosis-prone mouse models exhibited accelerated atherosclerosis with increased plaque macrophages and decreased plaque smooth muscle cell content. JAK2's essential role in growth hormone signalling in liver that resulted in reduced IGF-1 with hepatic Jak2 deficiency played a causal role in exacerbating atherosclerosis. As such, restoring IGF-1 either pharmacologically or genetically attenuated atherosclerotic burden. Together, our data show hepatic Jak2 to play a protective role in atherogenesis through actions mediated by circulating IGF-1 and, to our knowledge, provide a novel liver-centric mechanism in atheroprotection.
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Affiliation(s)
- Tharini Sivasubramaniyam
- Toronto General Hospital Research Institute, University Health Network, Toronto, Ontario, Canada.,Institute of Medical Science
| | - Stephanie A Schroer
- Toronto General Hospital Research Institute, University Health Network, Toronto, Ontario, Canada
| | - Angela Li
- Toronto General Hospital Research Institute, University Health Network, Toronto, Ontario, Canada.,Department of Immunology
| | - Cynthia T Luk
- Toronto General Hospital Research Institute, University Health Network, Toronto, Ontario, Canada.,Institute of Medical Science
| | - Sally Yu Shi
- Toronto General Hospital Research Institute, University Health Network, Toronto, Ontario, Canada.,Institute of Medical Science
| | - Rickvinder Besla
- Toronto General Hospital Research Institute, University Health Network, Toronto, Ontario, Canada.,Department of Laboratory Medicine and Pathobiology
| | - David W Dodington
- Toronto General Hospital Research Institute, University Health Network, Toronto, Ontario, Canada
| | - Adam H Metherel
- Department of Nutritional Sciences, University of Toronto, Toronto, Ontario, Canada
| | - Alex P Kitson
- Department of Nutritional Sciences, University of Toronto, Toronto, Ontario, Canada
| | - Jara J Brunt
- Toronto General Hospital Research Institute, University Health Network, Toronto, Ontario, Canada.,Institute of Medical Science
| | - Joshua Lopes
- Department of Laboratory Medicine and Pathobiology
| | - Kay-Uwe Wagner
- Eppley Institute for Research in Cancer and Allied Diseases and the Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, Nebraska, USA
| | - Richard P Bazinet
- Department of Nutritional Sciences, University of Toronto, Toronto, Ontario, Canada
| | - Michelle P Bendeck
- Department of Laboratory Medicine and Pathobiology.,Department of Physiology, University of Toronto, Toronto, Ontario, Canada
| | - Clinton S Robbins
- Toronto General Hospital Research Institute, University Health Network, Toronto, Ontario, Canada.,Department of Immunology.,Department of Laboratory Medicine and Pathobiology
| | - Minna Woo
- Toronto General Hospital Research Institute, University Health Network, Toronto, Ontario, Canada.,Institute of Medical Science.,Department of Immunology.,Division of Endocrinology and Metabolism, Department of Medicine, University Health Network, University of Toronto, Toronto, Ontario, Canada
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7
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Smiljanic K, Obradovic M, Jovanovic A, Djordjevic J, Dobutovic B, Jevremovic D, Marche P, Isenovic ER. Thrombin stimulates VSMC proliferation through an EGFR-dependent pathway: involvement of MMP-2. Mol Cell Biochem 2014; 396:147-60. [PMID: 25047892 DOI: 10.1007/s11010-014-2151-y] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2014] [Accepted: 07/11/2014] [Indexed: 01/23/2023]
Abstract
In this study, the role of epidermal growth factor receptor (EGFR), extracellular signal-regulated kinase (ERK1/2), heparin-binding EGF-like growth factor (HB-EGF), general metalloproteinases, matrix metalloproteinases-2 (MMP-2) in mediating the mitogenic action of thrombin in rat vascular smooth muscle cells (VSMC) was investigated. The incubation of rat VSMC with thrombin (1 U/ml) for 5 min resulted in significant (p < 0.001) increase of ERK1/2 phosphorylation by 8.7 ± 0.9-fold, EGFR phosphorylation by 8.5 ± 1.3-fold (p < 0.001) and DNA synthesis by 3.6 ± 0.4-fold (p < 0.001). Separate 30-min pretreatments with EGFR tyrosine kinase irreversible inhibitor, 10 µM PD169540 (PD), and 20 µM anti-HB-EGF antibody significantly reduced thrombin-stimulated EGFR and ERK1/2 phosphorylation by 81, 72 % and by 48 and 61 %, respectively. Furthermore, the same pretreatments with PD or anti-HB-EGF antibody reduced thrombin-induced VSMC proliferation by 44 and 45 %, respectively. In addition, 30-min pretreatments with 10 µM specific MMP-2 inhibitor significantly reduced thrombin-stimulated phosphorylation of both EGFR and ERK1/2 by 25 %. Moreover, the same pretreatment with MMP-2 inhibitor reduced thrombin-induced VSMC proliferation by 45 %. These results show that the thrombin-induced DNA synthesis correlates with the level of ERK1/2 activation rather than EGFR activation. These results further suggest that thrombin acts through EGFR and ERK 1/2 signaling pathways involving MMP-2 to upregulate proliferation of VSMC.
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Affiliation(s)
- Katarina Smiljanic
- Department of Biochemistry, Faculty of Chemistry, University of Belgrade, Studentski trg 16, 11000, Belgrade, Serbia,
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8
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Dobutovic B, Sudar E, Tepavcevic S, Djordjevic J, Djordjevic A, Radojcic M, Isenovic ER. Effects of ghrelin on protein expression of antioxidative enzymes and iNOS in the rat liver. Arch Med Sci 2014; 10:806-16. [PMID: 25276168 PMCID: PMC4175782 DOI: 10.5114/aoms.2014.44872] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/11/2012] [Revised: 01/14/2013] [Accepted: 02/24/2013] [Indexed: 01/17/2023] Open
Abstract
INTRODUCTION We investigated the effects of ghrelin on protein expression of the liver antioxidant enzymes superoxide dismutases (SODs), catalase (CAT), glutathione peroxidase (GPx), and glutathione reductase (GR), nuclear factor κB (NFκB) and inducible nitric oxide synthase (iNOS). Furthermore, we aimed to investigate whether extracellular regulated protein kinase (ERK1/2) and protein kinase B (Akt) are involved in ghrelin-regulated liver antioxidant enzymes and iNOS protein expression. MATERIAL AND METHODS Male Wistar rats were treated with ghrelin (0.3 nmol/5 µl) injected into the lateral cerebral ventricle every 24 h for 5 days, and 2 h after the last treatment the animals were sacrificed and the liver excised. The Western blot method was used to determine expression of antioxidant enzymes, iNOS, phosphorylation of Akt, ERK1/2 and nuclear factor κB (NFκB) subunits 50 and 65. RESULTS There was significantly higher protein expression of CuZnSOD (p < 0.001), MnSOD (p < 0.001), CAT (p < 0.001), GPx, (p < 0.001), and GR (p < 0.01) in the liver isolated from ghrelin-treated animals compared with control animals. In contrast, ghrelin significantly (p < 0.01) reduced protein expression of iNOS. In addition, phosphorylation of NFκB subunits p65 and p50 was significantly (p < 0.001 for p65; p < 0.05 for p50) reduced by ghrelin when compared with controls. Phosphorylation of ERK1/2 and of Akt was significantly higher in ghrelin-treated than in control animals (p < 0.05 for ERK1/2; p < 0.01 for Akt). CONCLUSIONS The results show that activation of Akt and ERK1/2 is involved in ghrelin-mediated regulation of protein expression of antioxidant enzymes and iNOS in the rat liver.
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Affiliation(s)
- Branislava Dobutovic
- Laboratory for Radiobiology and Molecular Genetics, Vinca Institute of Nuclear Sciences, University of Belgrade, Belgrade, Serbia
| | - Emina Sudar
- Laboratory for Radiobiology and Molecular Genetics, Vinca Institute of Nuclear Sciences, University of Belgrade, Belgrade, Serbia
| | - Snezana Tepavcevic
- Laboratory for Molecular Biology and Endocrinology, Vinca Institute of Nuclear Sciences, University of Belgrade, Belgrade, Serbia
| | - Jelena Djordjevic
- Laboratory for Molecular Biology and Endocrinology, Vinca Institute of Nuclear Sciences, University of Belgrade, Belgrade, Serbia
| | - Ana Djordjevic
- Laboratory for Molecular Biology and Endocrinology, Vinca Institute of Nuclear Sciences, University of Belgrade, Belgrade, Serbia
| | - Marija Radojcic
- Laboratory for Molecular Biology and Endocrinology, Vinca Institute of Nuclear Sciences, University of Belgrade, Belgrade, Serbia
| | - Esma R. Isenovic
- Laboratory for Radiobiology and Molecular Genetics, Vinca Institute of Nuclear Sciences, University of Belgrade, Belgrade, Serbia
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9
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Aroor A, McKarns S, Nistala R, DeMarco V, Gardner M, Garcia-Touza M, Whaley-Connell A, Sowers JR. DPP-4 Inhibitors as Therapeutic Modulators of Immune Cell Function and Associated Cardiovascular and Renal Insulin Resistance in Obesity and Diabetes. Cardiorenal Med 2013; 3:48-56. [PMID: 23946724 DOI: 10.1159/000348756] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/18/2013] [Accepted: 02/07/2013] [Indexed: 12/21/2022] Open
Abstract
The prevalence of obesity and diabetes continues to rise in the United States and worldwide. These findings parallel the expansion of childhood obesity and diabetes. Obesity is a central component of the cardiorenal metabolic syndrome (CRS) which increases the risk for cardiovascular disease (CVD) and chronic kidney disease (CKD). The hallmark of obesity, CRS, and early type 2 diabetes is insulin resistance, a result of decreased insulin metabolic signaling due, in part, to enhanced serine phosphorylation and/or proteasome-mediated degradation of the insulin receptor substrate. Cardiovascular and renal insulin resistance significantly contributes to endothelial dysfunction, impaired cardiac diastolic and vascular relaxation, glomerular injury, and tubular dysfunction. In this context, multiple factors including oxidative stress, increased inflammation, and inappropriate activation of the renin-angiotensin-aldosterone and the sympathetic nervous system contribute to overweight- and obesity-induced systemic and tissue insulin resistance. One common link between obesity and the development of insulin resistance appears to be a low-grade inflammatory response resulting from dysfunctional innate and adaptive immunity. In this regard, there has been recent work on the role of dipeptidyl peptidase-4 (DPP-4) in modulating innate and adaptive immunity. The direct effects of DPP-4 on immune cells and the indirect effects through GLP-1-dependent and -independent pathways suggest effects of DPP-4 inhibition may have beneficial effects beyond glycemic control in improving CVD and renal outcomes. Accordingly, this review addresses new insights into the role of DPP-4 in immune modulation and the potential beneficial effects of DPP-4 inhibitors in insulin resistance and associated CVD and CKD prevention.
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10
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Bojic T, Sudar E, Mikhailidis D, Alavantic D, Isenovic E. The role of G protein coupled receptor kinases in neurocardiovascular pathophysiology. Arch Med Sci 2012; 8:970-7. [PMID: 23319968 PMCID: PMC3542506 DOI: 10.5114/aoms.2012.29996] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/10/2012] [Revised: 06/14/2012] [Accepted: 06/29/2012] [Indexed: 12/15/2022] Open
Abstract
In coronary artery disease the G protein related kinases (GRKs) play a role in desensitization of β-adrenoreceptors (AR) after coronary occlusion. Targeted deletion and lowering of cardiac myocyte GRK-2 decreases the risk of post-ischemic heart failure (HF). Studies carried out in humans confirm the role of GRK-2 as a marker for the progression of HF after myocardial infarction (MI). The level of GRK-2 could be an indicator of β-AR blocker efficacy in patients with acute coronary syndrome. Elevated levels of GRK-2 are an early ubiquitous consequence of myocardial injury. In hypertension an increased level of GRK-2 was reported in both animal models and human studies. The role of GRKs in vagally mediated disorders such as vasovagal syncope and atrial fibrillation remains controversial. The role of GRKs in the pathogenesis of neurocardiological diseases provides an insight into the molecular pathogenesis process, opens potential therapeutic options and suggests new directins for scientific research.
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Affiliation(s)
- Tijana Bojic
- Institute of Nuclear Sciences Vinča, University of Belgrade, Laboratory of Radiobiology and Molecular Genetics, Belgrade, Serbia
| | - Emina Sudar
- Institute of Nuclear Sciences Vinča, University of Belgrade, Laboratory of Radiobiology and Molecular Genetics, Belgrade, Serbia
| | - Dimitri Mikhailidis
- Department of Clinical Biochemistry (Vascular Disease Prevention Clinics), Royal Free Hospital Campus, University College London Medical School, UK
| | - Dragan Alavantic
- Institute of Nuclear Sciences Vinča, University of Belgrade, Laboratory of Radiobiology and Molecular Genetics, Belgrade, Serbia
| | - Esma Isenovic
- Institute of Nuclear Sciences Vinča, University of Belgrade, Laboratory of Radiobiology and Molecular Genetics, Belgrade, Serbia
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11
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Cheng PW, Lu PJ, Chen SR, Ho WY, Cheng WH, Hong LZ, Yeh TC, Sun GC, Wang LL, Hsiao M, Tseng CJ. Central nicotinic acetylcholine receptor involved in Ca(2+) -calmodulin-endothelial nitric oxide synthase pathway modulated hypotensive effects. Br J Pharmacol 2011; 163:1203-13. [PMID: 21091651 DOI: 10.1111/j.1476-5381.2010.01124.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
BACKGROUND AND PURPOSE Recent evidence has suggested that nicotine decreases blood pressure (BP) and heart rate (HR) in the nucleus tractus solitarii (NTS), indicating that nicotinic acetylcholine receptors (nAChRs) play an important role in BP control in the NTS. However, the signalling mechanisms involved in nAChR-mediated depressor effects in the NTS are unclear. Hence, the aim of this study was to investigate these signalling mechanisms. EXPERIMENTAL APPROACH Depressor responses to nicotine microinjected into the NTS of Wistar-Kyoto rats were elicited in the absence and presence of an antagonist of α7 nAChR, the calcium chelator ethylene glycol tetraacetic acid, a calmodulin-specific inhibitor, nitric oxide (NO) synthase (NOS) inhibitor, endothelial NOS (eNOS)-selective inhibitor or neuronal NOS (nNOS)-specific inhibitor. KEY RESULTS Microinjection of nicotine into the NTS produced a dose-dependent decrease in BP and HR, and increased nitrate levels. This depressor effect of nicotine was attenuated after pretreatment with a nAChR antagonist or blockers of the calmodulin-eNOS pathway. In contrast, N5-(1-Imino-3-butenyl)-L-ornithine (vinyl-L-NIO), nNOS-specific inhibitor, did not diminish these nicotine-mediated effects. Calmodulin was found to bind eNOS after nicotine injection into NTS. However, nicotine did not affect the eNOS phosphorylation level or eNOS upstream extracellular signal-regulated kinases (ERK)1/2 and Akt phosphorylation levels. Furthermore, pretreatment with an ERK1/2 or Akt inhibitor did not attenuate nicotine-induced depressor effects in the NTS. CONCLUSIONS AND IMPLICATIONS These results suggest that the nAChR-Ca(2+) -calmodulin-eNOS-NO signalling pathway, but not nNOS, plays a significant role in central BP regulation, and neither the ERK1/2 nor Akt signalling pathway are significantly involved in the activation of eNOS by nAChRs in the NTS.
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Affiliation(s)
- Pei-Wen Cheng
- Department of Medical Education and Research, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan
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12
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Soskić SS, Dobutović BD, Sudar EM, Obradović MM, Nikolić DM, Djordjevic JD, Radak DJ, Mikhailidis DP, Isenović ER. Regulation of Inducible Nitric Oxide Synthase (iNOS) and its Potential Role in Insulin Resistance, Diabetes and Heart Failure. Open Cardiovasc Med J 2011; 5:153-63. [PMID: 21792376 PMCID: PMC3141344 DOI: 10.2174/1874192401105010153] [Citation(s) in RCA: 110] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2011] [Revised: 05/30/2011] [Accepted: 05/31/2011] [Indexed: 02/08/2023] Open
Abstract
Nitric oxide synthases (NOS) are the enzymes responsible for nitric oxide (NO) generation. NO is a reactive oxygen species as well as a reactive nitrogen species. It is a free radical which mediates several biological effects. It is clear that the generation and actions of NO under physiological and pathophysiological conditions are regulated and extend to almost every cell type and function within the circulation. In mammals 3 distinct isoforms of NOS have been identified: neuronal NOS (nNOS), inducible NOS (iNOS) and endothelial NOS (eNOS). The important isoform in the regulation of insulin resistance (IR) is iNOS. Understanding the molecular mechanisms regulating the iNOS pathway in normal and hyperglycemic conditions would help to explain some of vascular abnormalities observed in type 2 diabetes mellitus (T2DM). Previous studies have reported increased myocardial iNOS activity and expression in heart failure (HF). This review considers the recent animal studies which focus on the understanding of regulation of iNOS activity/expression and the role of iNOS agonists as potential therapeutic agents in treatment of IR, T2DM and HF.
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Affiliation(s)
- Sanja S Soskić
- Laboratory for Radiobiology and Molecular Genetics, Institute "Vinča", University of Belgrade, Serbia
| | - Branislava D Dobutović
- Laboratory for Radiobiology and Molecular Genetics, Institute "Vinča", University of Belgrade, Serbia
| | - Emina M Sudar
- Laboratory for Radiobiology and Molecular Genetics, Institute "Vinča", University of Belgrade, Serbia
| | - Milan M Obradović
- Laboratory for Radiobiology and Molecular Genetics, Institute "Vinča", University of Belgrade, Serbia
| | - Dragana M Nikolić
- Laboratory for Radiobiology and Molecular Genetics, Institute "Vinča", University of Belgrade, Serbia
| | - Jelena D Djordjevic
- Institute of Physiology and Biochemistry, Faculty of Biology, University of Belgrade, Studentski trg 16, 11000 Belgrade, P.O.Box S2 Republic of Serbia
| | - Djordje J Radak
- Department of Vascular Surgery, Dedinje Cardiovascular Institute, Belgrade University School of Medicine, Belgrade, Serbia
| | - Dimitri P Mikhailidis
- Department of Clinical Biochemistry (Vascular Disease Prevention Clinics), Royal Free campus, University College London Medical School, University College London (UCL), Pond Street, London NW3 2QG, UK
| | - Esma R Isenović
- Laboratory for Radiobiology and Molecular Genetics, Institute "Vinča", University of Belgrade, Serbia
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13
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Pulakat L, DeMarco VG, Whaley-Connell A, Sowers JR. The Impact of Overnutrition on Insulin Metabolic Signaling in the Heart and the Kidney. Cardiorenal Med 2011; 1:102-112. [PMID: 22258397 DOI: 10.1159/000327140] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Overnutrition characterized by overconsumption of food rich in fat and carbohydrates is a significant contributor to hypertension, type 2 diabetes, and the cardiorenal syndrome. Overnutrition activates the renin-angiotensin-aldosterone system (RAAS) and causes chronic exposure of cardiovascular and renal tissue to increased circulating nutrients, insulin (INS), and angiotensin II (ANG II). Emerging evidence suggests that overnutrition, aldosterone, and ANG II promote INS resistance, a chronic condition that underlies these co-morbidities, through activation of the mammalian target of the rapamycin (mTOR)/S6 kinase 1 (S6K1) signaling pathway in cardiovascular tissue and the kidney. However, a novel ANG II type 2 receptor (AT2R)-mediated cross talk between the RAAS and mTOR pathways ameliorates overnutrition-induced activation of mTOR/S6K1 signaling in cardiovascular tissue of rats, mice, and humans and confers cardioprotection.
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14
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Takenouchi Y, Kobayashi T, Taguchi K, Matsumoto T, Kamata K. Gender differences in vascular reactivity of aortas from streptozotocin-induced diabetic mice. Biol Pharm Bull 2011; 33:1692-7. [PMID: 20930377 DOI: 10.1248/bpb.33.1692] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The aim of the present study was to assess gender differences in diabetes-related vascular reactivity in murine aortas. Diabetes is a risk factor for ischemic heart disease, cerebral ischemia, and atherosclerosis, conditions in which endothelial dysfunction plays a pathogenetic role. We examined vascular responses in aortas isolated from streptozotocin (STZ)-induced type 1 diabetic mice and age-matched control mice, and looked for gender differences in the diabetes-induced changes in these responses. For each gender, the plasma adiponectin levels were lower in diabetic mice than in the controls, and they were significantly higher in females than in males. The acetylcholine (ACh)-induced endothelium-dependent relaxation of aortic rings was impaired (vs. that in the age-matched controls) in diabetic male mice, but not in diabetic female mice. The sodium nitroprusside-induced endothelium-independent aortic relaxation was not altered by diabetes in either male or female mice. The norepinephrine-induced aortic contraction was enhanced (vs. that in the control group) in diabetic female mice, but not in diabetic male mice, whereas in the presence of N(G)-nitro-L-arginine neither gender exhibited a significant diabetes-induced change in this contraction. The clonidine-induced and insulin-induced endothelium-dependent aortic relaxations were impaired only in the diabetic female group (vs. the age-matched controls). These results suggest that: a) in male diabetic mice, which exhibited low adiponectin levels, these were impairments of both the aortic relaxation and nitric oxide (NO) production induced by ACh, whereas b) in female diabetic mice, there were impairments of the aortic relaxations induced by both insulin and clonidine.
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Affiliation(s)
- Yasuhiro Takenouchi
- Department of Physiology and Morphology, Institute of Medicinal Chemistry, Hoshi University, Tokyo 142–8501, Japan
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15
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Balligand JL, Feron O, Dessy C. eNOS activation by physical forces: from short-term regulation of contraction to chronic remodeling of cardiovascular tissues. Physiol Rev 2009; 89:481-534. [PMID: 19342613 DOI: 10.1152/physrev.00042.2007] [Citation(s) in RCA: 315] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Nitric oxide production in response to flow-dependent shear forces applied on the surface of endothelial cells is a fundamental mechanism of regulation of vascular tone, peripheral resistance, and tissue perfusion. This implicates the concerted action of multiple upstream "mechanosensing" molecules reversibly assembled in signalosomes recruiting endothelial nitric oxide synthase (eNOS) in specific subcellular locales, e.g., plasmalemmal caveolae. Subsequent short- and long-term increases in activity and expression of eNOS translate this mechanical stimulus into enhanced NO production and bioactivity through a complex transcriptional and posttranslational regulation of the enzyme, including by shear-stress responsive transcription factors, oxidant stress-dependent regulation of transcript stability, eNOS regulatory phosphorylations, and protein-protein interactions. Notably, eNOS expressed in cardiac myocytes is amenable to a similar regulation in response to stretching of cardiac muscle cells and in part mediates the length-dependent increase in cardiac contraction force. In addition to short-term regulation of contractile tone, eNOS mediates key aspects of cardiac and vascular remodeling, e.g., by orchestrating the mobilization, recruitment, migration, and differentiation of cardiac and vascular progenitor cells, in part by regulating the stabilization and transcriptional activity of hypoxia inducible factor in normoxia and hypoxia. The continuum of the influence of eNOS in cardiovascular biology explains its growing implication in mechanosensitive aspects of integrated physiology, such as the control of blood pressure variability or the modulation of cardiac remodeling in situations of hemodynamic overload.
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Affiliation(s)
- J-L Balligand
- Unit of Pharmacology and Therapeutics, Université catholique de Louvain, Brussels, Belgium.
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16
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17
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Carey RM. Pathophysiology of Primary Hypertension. Microcirculation 2008. [DOI: 10.1016/b978-0-12-374530-9.00020-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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18
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Holzman JL, Liu L, Duke BJ, Kemendy AE, Eaton DC. Transactivation of the IGF-1R by aldosterone. Am J Physiol Renal Physiol 2007; 292:F1219-28. [PMID: 17190911 DOI: 10.1152/ajprenal.00214.2006] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Activation of epithelial sodium channels (ENaC) by aldosterone, insulin, or insulin-like growth factor-1 (IGF-1) in renal epithelial cells (including the Xenopus laevis renal cell line A6) appears to share some common signaling elements subsequent to the initial insulin or IGF-1 receptor activation. Previously, the convergence point for insulin or IGF-1 and aldosterone signaling was assumed to be downstream of the receptor at the level of phosphatidylinositol 3-kinase (PI3-K); however, this study shows aldosterone directly transactivates the IGF-1 receptor (IGF-1R). In A6 cells, 10-min exposure to aldosterone increased the phosphorylation of the IGF-1 receptor, insulin receptor substrate-1 (IRS-1), and Akt (PKB). Furthermore, aldosterone activated PI3-K and phosphorylation of the most downstream element, Akt, was blocked by the specific PI3-K inhibitor LY-294002. Transactivation requires aldosterone binding to the mineralocorticoid/glucocorticoid receptor and does not require transcription.
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Affiliation(s)
- Jennifer L Holzman
- Emory Univ. School of Medicine, Dept. of Medicine, Renal Div., 1639 Pierce Dr., Rm. 3327, Atlanta, GA 30322, USA.
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19
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Yang AL, Su CT, Lin KL, Chao JI, You HP, Lee SD. Exercise training improves insulin-induced and insulin-like growth factor-1-induced vasorelaxation in rat aortas. Life Sci 2006; 79:2017-21. [PMID: 16889802 DOI: 10.1016/j.lfs.2006.06.037] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2006] [Revised: 05/03/2006] [Accepted: 06/25/2006] [Indexed: 11/27/2022]
Abstract
Improved vasorelaxant response is one of the beneficial effects of exercise training on vascular function. The mechanism for this response is, however, poorly understood. The aim of this study was to investigate the effects of exercise training on insulin-induced and insulin-like growth factor-1 (IGF-1)-induced vasorelaxation. Fourteen 6-week-old male Wistar rats were randomly divided into sedentary control and exercise groups. For 12 weeks, the exercise group ran on a treadmill 60 min/day, 5 days/week. After exercise training, insulin-induced and IGF-1-induced vasorelaxant responses were evaluated by measuring the isometric tension of aortic rings. The vasorelaxant role of phosphatidylinositol 3-kinase (PI3K) and nitric oxide synthase (NOS) was examined by applying inhibitors, such as wortmannin (an inhibitor of PI3K) and N(omega)-nitro-L-arginine methyl ester (L-NAME, a NOS inhibitor). In addition, we examined the vascular response to the NO donor, sodium nitroprusside (SNP). We found that: (1) exercise training significantly enhanced both insulin-induced and IGF-1-induced vasorelaxation in rat aortas; (2) this vasorelaxant effect disappeared after the use of wortmannin or L-NAME; (3) there was no significant difference in SNP-induced vasorelaxation between control and exercise groups. Our findings indicate that exercise training enhances insulin-induced and IGF-1-induced vasorelaxant responses which are mediated through the PI3K-NOS-dependent pathway.
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Affiliation(s)
- Ai-Lun Yang
- Department of Physical Therapy, College of Medicine, National Cheng Kung University, Tainan, Taiwan
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20
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Kobayashi T, Taguchi K, Yasuhiro T, Matsumoto T, Kamata K. Impairment of PI3-K/Akt Pathway Underlies Attenuated Endothelial Function in Aorta of Type 2 Diabetic Mouse Model. Hypertension 2004; 44:956-62. [PMID: 15505117 DOI: 10.1161/01.hyp.0000147559.10261.a7] [Citation(s) in RCA: 113] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The phosphatidylinositol 3-kinase (PI3-K) pathway, which activates serine/threonine protein kinase Akt, enhances endothelial nitric oxide synthase (eNOS) phosphorylation and nitric oxide (NO) production. We investigated the involvement of the PI3-K/Akt pathway in the relaxation responses to acetylcholine (ACh) and clonidine in a new type 2 diabetic model (streptozotocin plus nicotinamide-induced diabetic mice). Plasma glucose and insulin levels were significantly elevated in our model, and intravenous glucose tolerance tests revealed clear abnormalities in glucose tolerance and insulin responsiveness. Although in our model the ACh-induced relaxation and NO
x
−
(NO
2
−
+NO
3
−
)/cGMP production were unchanged, the clonidine-induced and insulin-induced relaxations and NO
x
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/cGMP production were all greatly attenuated. In control mice, the clonidine-induced and insulin-induced relaxations were each abolished by LY294002 and by Wortmannin (inhibitors of PI3-K), and also by Akt-inhibitor treatment. The ACh-induced relaxation was unaffected by such treatments in either group of mice. The expression level of total Akt protein was significantly decreased in the diabetic mice aorta, but those for the p85 and p110γ subunits of PI3-K were not. The clonidine-induced Ser-473 phosphorylation of Akt through PI3-K was significantly decreased in our model; however, that induced by ACh was not. These results suggest that relaxation responses and NO production mediated via the PI3-K/Akt pathway are decreased in this type 2 diabetic model. This may be a major cause of endothelial dysfunction (and the resulting hypertension) in type 2 diabetes.
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Affiliation(s)
- Tsuneo Kobayashi
- Department of Physiology and Morphology, Institute of Medicinal Chemistry, Hoshi University, Shinagawa-ku, Tokyo, Japan
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21
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Abstract
Diminished insulin (Ins) sensitivity is a characteristic feature of various pathological conditions such as the cardiometabolic syndrome, Type 2 diabetes, and hypertension. Persons with essential hypertension are more prone than normotensive persons to develop diabetes, and this propensity may reflect decreased ability of Ins to promote relaxation and glucose transport in vascular and skeletal muscle tissue, respectively. There are increasing data suggesting that ANG II acting through its ANG type 1 receptor inhibits the actions of Ins in vascular and skeletal muscle tissue, in part, by interfering with Ins signally through phosphatidylinositol 3-kinase (PI3K) and its downstream protein kinase B (Akt) signaling pathways. This inhibitory action of ANG II is mediated, in part, through stimulation of RhoA activity and oxidative stress. Activated RhoA and increased reactive oxygen species inhibition of PI3K/Akt signaling results in decreased endothelial cell production of nitric oxide, increased myosin light chain activation with vasoconstriction, and reduced skeletal muscle glucose transport.
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22
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González M, Flores C, Pearson JD, Casanello P, Sobrevia L. Cell signalling-mediating insulin increase of mRNA expression for cationic amino acid transporters-1 and -2 and membrane hyperpolarization in human umbilical vein endothelial cells. Pflugers Arch 2004; 448:383-94. [PMID: 15064952 DOI: 10.1007/s00424-004-1261-x] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2003] [Accepted: 02/24/2004] [Indexed: 01/04/2023]
Abstract
Insulin induces vasodilatation in human subjects and increases L-arginine transport and NO synthesis in human umbilical vein endothelial cells (HUVEC). Cell signalling events associated with insulin effects on activity and mRNA expression of the human cationic amino acid transporters 1 (hCAT-1) and 2B (hCAT-2B) are unknown. L-arginine transport and eNOS activity were determined in HUVEC exposed to insulin. mRNA levels for hCAT-1, hCAT-2B and eNOS were quantitated by real time RT-PCR and endothelial NO synthase (eNOS) protein was identified by Western blot analysis. Intracellular Ca2+, L-arginine and L-citrulline levels, L-[3H]citrulline formation from L-[(3)H]arginine, cGMP formation, nitrite level, ATP release and membrane potential were determined. Insulin increased L-arginine transport and the mRNA levels for hCAT-1 and hCAT-2B and eNOS expression and activity. Insulin also induced membrane hyperpolarization and increased intracellular Ca2+, L-[3H]citrulline, cGMP and nitrite formation. Insulin-mediated stimulation of the L-arginine/NO pathway is thus associated with increased hCAT-1 and hCAT-2B mRNA, and eNOS expression, via mechanisms involving membrane hyperpolarization, mitogen-activated protein kinases p42 and p44, phosphatidylinositol 3-kinase, NO and protein kinase C. We have characterized a cell signalling pathway by which hyperinsulinaemia could lead to vasodilatation in human subjects, and which could have implications in patients in whom plasma insulin levels are altered, such as in diabetes mellitus.
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Affiliation(s)
- Marcelo González
- Cellular and Molecular Physiology Laboratory (CMPL), Department of Obstetrics and Gynaecology, Medical Research Centre (CIM), School of Medicine, Faculty of Medicine, Pontificia Universidad Católica de Chile, P.O. Box 114-D, Santiago, Chile
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23
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Isenovic ER, Jacobs DB, Kedees MH, Sha Q, Milivojevic N, Kawakami K, Gick G, Sowers JR. Angiotensin II regulation of the Na+ pump involves the phosphatidylinositol-3 kinase and p42/44 mitogen-activated protein kinase signaling pathways in vascular smooth muscle cells. Endocrinology 2004; 145:1151-60. [PMID: 14630723 DOI: 10.1210/en.2003-0100] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
This investigation used primary cultured rat vascular smooth muscle cells to examine angiotensin II (Ang II) regulation of Na(+), K(+)-ATPase (Na(+) pump) activity, and Na(+) pump alpha(1)- and beta(1)-subunit gene transcription. This regulation was mediated through both phosphatidylinositol-3 kinase (PI3K) and p42/44 mitogen-activated protein kinase (p42/44(MAPK)) signaling pathways. Both acute (10 min) and prolonged (24 h) treatment with Ang II stimulated Na(+) pump activity. Also, prolonged exposure to Ang II (24 h) increased promoter transcription of the Na(+) pump alpha(1)- and beta(1)-subunits. Furthermore, PI3K activities because well because p42/44(MAPK) phosphorylation were increased within 10 min after Ang II treatment. To determine whether these stimulatory activities of Ang II are acting through Ang II receptors 1 and/or 2 (AT(1), AT(2)), cells were pretreated with either AT(1) receptor blocker losartan or the AT(2) receptor blocker PD 123,319. Indeed, these treatments prevented the stimulatory effect of Ang II on Na(+) pump activity at both acute and 24-h time points. Furthermore, the Ang II-stimulated alpha(1)-subunit promoter transcription was inhibited by losartan but not by the AT(2) receptor blocker. These results indicate that Ang II acts through both the AT(1) and AT(2) receptor to up-regulate Na(+) pump activity; however, Ang II regulates alpha(1)-gene transcription through AT(1) but not AT(2) receptors. It was also observed that the Ang II-stimulated beta(1)-subunit gene transcription is not mediated through either AT(1) or AT(2) receptors. To examine whether the Na(+)/H(+) exchanger is involved in Ang II-stimulated Na(+) pump activity, cells were pretreated with amiloride, a specific inhibitor of the Na(+)/H(+) exchanger. This pretreatment prevented 24 h, but not acute, Ang II-stimulated Na(+) pump activity. The 24-h Ang II-stimulated alpha(1)-subunit promoter transcription was also inhibited by amiloride. This suggests that the prolonged effect of Ang II on Na(+) pump activity is dependent on increased Na(+)/H(+) exchange. Because Ang II treatment for 10 min increased PI3K activity because well because p42/44(MAPK) phosphorylation, studies were performed to determine the involvement of PI3K and p42/44(MAPK) signaling pathways in both Ang II-stimulated Na(+) pump activity and alpha(1)- and beta(1)-gene transcription. Cells were pretreated with either the PI3K inhibitor wortmannin or the p42/44(MAPK) inhibitor PD 98059. Ang II-stimulated PI3K or p42/44(MAPK) activity was inhibited by these pretreatments. Furthermore, pretreatment of cells with the PI3K inhibitors wortmannin and LY29404 or the MAPK inhibitors U0126 and PD 98059 were all observed to inhibit Ang II-stimulated Na(+) pump activity. To more specifically determine the role of PI3K in Ang II-regulation of alpha(1)-and beta(1)-gene transcription, cells were cotransfected with a dominant-negative p85 construct. Cotransfection with dominant-negative p85 reduced Ang II-stimulated alpha(1)-but not beta(1)-gene transcription in vascular smooth muscle cells. These results indicate that Ang II acts through PI3K/p42/44(MAPK) signaling pathways to up-regulate Na(+) pump activity and alpha(1)-gene transcription and that Ang II-regulated beta(1)-gene transcription is not mediated through either PI3K or p42/44 (MAPK) signaling pathways.
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MESH Headings
- Amiloride/pharmacology
- Angiotensin II/pharmacology
- Animals
- Antihypertensive Agents/pharmacology
- Aorta, Thoracic/cytology
- Biological Transport/drug effects
- Biological Transport/physiology
- Cells, Cultured
- Diuretics/pharmacology
- Losartan/pharmacology
- MAP Kinase Signaling System/drug effects
- MAP Kinase Signaling System/physiology
- Mitogen-Activated Protein Kinase 1/metabolism
- Mitogen-Activated Protein Kinase 3
- Mitogen-Activated Protein Kinases/metabolism
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/metabolism
- Phosphatidylinositol 3-Kinases/metabolism
- Rats
- Rats, Sprague-Dawley
- Receptor, Angiotensin, Type 1/genetics
- Sodium-Potassium-Exchanging ATPase/metabolism
- Transcription, Genetic/drug effects
- Vasoconstrictor Agents/pharmacology
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Affiliation(s)
- Esma R Isenovic
- Department of Cell Biology, State University of New York-Health Science Center, Brooklyn, 11201, USA
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24
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Sowers JR, Frohlich ED. Insulin and insulin resistance: impact on blood pressure and cardiovascular disease. Med Clin North Am 2004; 88:63-82. [PMID: 14871051 DOI: 10.1016/s0025-7125(03)00128-7] [Citation(s) in RCA: 109] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Cardiovascular disease is a major cause of mortality in individuals with diabetes. Many factors, including hypertension, contribute to the high prevalence of CVD in this population. Hypertension occurs approximately twice as frequently in patients with diabetes compared with patients without diabetes. Conversely, recent data suggest that hypertensive persons are more likely to develop diabetes than normotensive persons. In addition, up to 75% of CVD in patients with diabetes may be attributed to hypertension, leading to recommendations for more aggressive blood pressure control (ie, < 130/85 mm Hg) in persons with coexistent diabetes and hypertension. Increasing obesity further contributes to both diabetes and hypertension and significantly increases CVD morbidity and mortality. Other important risk factors for CVD in these patients include atherosclerosis, dyslipidemia, microalbuminuria, endothelial dysfunction, platelet hyperaggregability, coagulation abnormalities, and diabetic cardiomyopathy. The current knowledge regarding these risk factors has been reviewed, placing special emphasis on the metabolic syndrome, hypertension, microalbuminuria, and the role of obesity in these disorders. Although not discussed in detail, it is acknowledged that both hygienic measures (weight loss and aerobic exercise) and treatment strategies that include aspirin, statins, INS sensitizers, and antihypertensive agents that reduce renin-angiotensin-aldosterone system activity have been shown to reduce inflammation, coagulation abnormalities, endothelial function, proteinuria, and in some cases reduce CVD and renal disease progression. Additional therapeutic agents are currently being developed specifically to improve INS sensitivity and other CVD risk factors that are components of the cardiometabolic syndrome.
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Affiliation(s)
- James R Sowers
- Division of Endocrinology, Diabetes and Hypertension, SUNY Downstate and VAMC, 450 Clarkson Avenue, Box 1205, Brooklyn, NY 11203, USA.
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25
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Delafontaine P, Song YH, Li Y. Expression, regulation, and function of IGF-1, IGF-1R, and IGF-1 binding proteins in blood vessels. Arterioscler Thromb Vasc Biol 2003; 24:435-44. [PMID: 14604834 DOI: 10.1161/01.atv.0000105902.89459.09] [Citation(s) in RCA: 391] [Impact Index Per Article: 18.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The vascular insulin-like growth factor (IGF)-1 system includes the IGFs, the IGF-1 receptor (IGF-1R), and multiple binding proteins. This growth factor system exerts multiple physiologic effects on the vasculature through both endocrine and autocrine/paracrine mechanisms. The effects of IGF-1 are mediated principally through the IGF-1R but are modulated by complex interactions with multiple IGF binding proteins that themselves are regulated by phosphorylation, proteolysis, polymerization, and cell or matrix association. During the last decade, a significant body of evidence has accumulated, indicating that expression of the components of the IGF system are regulated by multiple factors, including growth factors, cytokines, lipoproteins, reactive oxygen species, and hemodynamic forces. In addition, cross-talk between the IGF system and other growth factors and integrin receptors has been demonstrated. There is accumulating evidence of a role for IGF-1 in multiple vascular pathologies, including atherosclerosis, hypertension, restenosis, angiogenesis, and diabetic vascular disease. This review will discuss the regulation of expression of IGF-1, IGF-1R, and IGF binding proteins in the vasculature and summarize evidence implicating involvement of this system in vascular diseases.
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Affiliation(s)
- Patrice Delafontaine
- Section of Cardiology, School of Medicine, Tulane University Medical Center, 1430 Tulane Ave, New Orleans, LA 70112-2699, USA.
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McCarty MF. IGF-I activity may be a key determinant of stroke risk--a cautionary lesson for vegans. Med Hypotheses 2003; 61:323-34. [PMID: 12944100 DOI: 10.1016/s0306-9877(02)00241-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
IGF-I acts on vascular endothelium to activate nitric oxide synthase, thereby promoting vascular health; there is reason to believe that this protection is especially crucial to the cerebral vasculature, helping to ward off thrombotic strokes. IGF-I may also promote the structural integrity of cerebral arteries, thereby offering protection from hemorrhagic stroke. These considerations may help to explain why tallness is associated with low stroke risk, whereas growth hormone deficiency increases stroke risk--and why age-adjusted stroke mortality has been exceptionally high in rural Asians eating quasi-vegan diets, but has been declining steadily in Asia as diets have become progressively higher in animal products. There is good reason to suspect that low-fat vegan diets tend to down-regulate systemic IGF-I activity; this effect would be expected to increase stroke risk in vegans. Furthermore, epidemiology suggests that low serum cholesterol, and possibly also a low dietary intake of saturated fat--both characteristic of those adopting low-fat vegan diets--may also increase stroke risk. Vegans are thus well advised to adopt practical countermeasures to minimize stroke risk--the most definitive of which may be salt restriction. A high potassium intake, aerobic exercise training, whole grains, moderate alcohol consumption, low-dose aspirin, statin or policosanol therapy, green tea, and supplementation with fish oil, taurine, arginine, and B vitamins--as well as pharmacotherapy of hypertension if warranted--are other practical measures for lowering stroke risk. Although low-fat vegan diets may markedly reduce risk for coronary disease, diabetes, and many common types of cancer, an increased risk for stroke may represent an 'Achilles heel'. Nonetheless, vegans have the potential to achieve a truly exceptional 'healthspan' if they face this problem forthrightly by restricting salt intake and taking other practical measures that promote cerebrovascular health.
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Affiliation(s)
- M F McCarty
- Pantox Laboratories, San Diego, California 92109, USA
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McCarty MF. A low-fat, whole-food vegan diet, as well as other strategies that down-regulate IGF-I activity, may slow the human aging process. Med Hypotheses 2003; 60:784-92. [PMID: 12699704 DOI: 10.1016/s0306-9877(02)00235-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
A considerable amount of evidence is consistent with the proposition that systemic IGF-I activity acts as pacesetter in the aging process. A reduction in IGF-I activity is the common characteristic of rodents whose maximal lifespan has been increased by a wide range of genetic or dietary measures, including caloric restriction. The lifespans of breeds of dogs and strains of rats tend to be inversely proportional to their mature weight and IGF-I levels. The link between IGF-I and aging appears to be evolutionarily conserved; in worms and flies, lifespan is increased by reduction-of-function mutations in signaling intermediates homologous to those which mediate insulin/IGF-I activity in mammals. The fact that an increase in IGF-I activity plays a key role in the induction of sexual maturity, is consistent with a broader role for-IGF-I in aging regulation. If down-regulation of IGF-I activity could indeed slow aging in humans, a range of practical measures for achieving this may be at hand. These include a low-fat, whole-food, vegan diet, exercise training, soluble fiber, insulin sensitizers, appetite suppressants, and agents such as flax lignans, oral estrogen, or tamoxifen that decrease hepatic synthesis of IGF-I. Many of these measures would also be expected to decrease risk for common age-related diseases. Regimens combining several of these approaches might have a sufficient impact on IGF-I activity to achieve a useful retardation of the aging process. However, in light of the fact that IGF-I promotes endothelial production of nitric oxide and may be of especial importance to cerebrovascular health, additional measures for stroke prevention-most notably salt restriction-may be advisable when attempting to down-regulate IGF-I activity as a pro-longevity strategy.
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Isenovic ER, Divald A, Milivojevic N, Grgurevic T, Fisher SE, Sowers JR. Interactive effects of insulin-like growth factor-1 and beta-estradiol on endothelial nitric oxide synthase activity in rat aortic endothelial cells. Metabolism 2003; 52:482-7. [PMID: 12701063 DOI: 10.1053/meta.2003.50079] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Insulin-like growth factor-1 (IGF-1) and beta-estradiol (E2) have vasodilatory effects, in part, through stimulation of vascular nitric oxide (NO) production. However, their interactive effects on endothelial nitric oxide synthase (eNOS) and NO production have not been previously studied in endothelial cells (EC). Employing rat aortic EC (RAEC), the effects of acute (20 and 30 minutes) and prolonged (4 hours) stimulation with 100 nmol/L IGF-1 and 1 nmol/L E2 (alone or in combination) were assessed with respect to protein levels and enzymatic activities for phosphatidyl inositol 3-kinase (PI3K) and serine/threonine kinase Akt (Akt), enzymes involved in eNOS activation. Exposure to IGF-1 for 30 minutes or E2 for 20 minutes increased insulin receptor substrate-1 (IRS-1) association with the regulatory (p85) subunit of PI3K, enhanced tyrosine phosphorylation of p85, and increased PI3K activity. Combined treatment had a greater effect on p85 phosphorylation and PI3K activity then either agonist alone. Moreover, IGF-1 and E2 enhanced Akt Ser(473) phosphorylation, with the effect of IGF-1 being much greater. Acute expose to both E2 (20 minutes) and IGF-1 (30 minutes) were associated with an increase in eNOS activity. Prolonged exposure (4 hours) to either IGF-1 or E2 increased expression of the p85 subunit as well as eNOS activity. Pretreatment with PI3K antagonist wortmannin (WT) prevented this increase in eNOS activity. The results suggest that IGF-1 and E2 may interact through PI3K/Akt-related pathways to increase eNOS activity.
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Affiliation(s)
- Esma R Isenovic
- Department of Medicine, SUNY-Health Science Center, Brooklyn 11203, USA
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Flores C, Rojas S, Aguayo C, Parodi J, Mann G, Pearson JD, Casanello P, Sobrevia L. Rapid stimulation of L-arginine transport by D-glucose involves p42/44(mapk) and nitric oxide in human umbilical vein endothelium. Circ Res 2003; 92:64-72. [PMID: 12522122 DOI: 10.1161/01.res.0000048197.78764.d6] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
D-glucose infusion and gestational diabetes induce vasodilatation in humans and increase L-arginine transport and nitric oxide (NO) synthesis in human umbilical vein endothelial cells. High D-glucose (25 mmol/L, 2 minutes) induced membrane hyperpolarization and an increase of L-arginine transport (V(max) 6.1+/-0.7 versus 4.4+/-0.1 pmol/ microg protein per minute) with no change in transport affinity (K(m) 105+/-9 versus 111+/-16 micromol/L). L-[3H]citrulline formation and intracellular cGMP, but not intracellular Ca2+, were increased by high D-glucose. The effects of D-glucose were mimicked by levcromakalim (ATP-sensitive K+ channel blocker), paralleled by p42/p44(mapk) and Ser(1177)-endothelial NO synthase phosphorylation, inhibited by N(G)-nitro-L-arginine methyl ester (L-NAME; NO synthesis inhibitor), glibenclamide (ATP-sensitive K+ channel blocker), KT-5823 (protein kinase G inhibitor), PD-98059 (mitogen-activated protein kinase kinase 1/2 inhibitor), and wortmannin (phosphatidylinositol 3-kinase inhibitor), but they were unaffected by calphostin C (protein kinase C inhibitor). Elevated D-glucose did not alter superoxide dismutase activity. Our findings demonstrate that the human fetal endothelial L-arginine/NO signaling pathway is rapidly activated by elevated D-glucose via NO and p42/44(mapk). This could be determinant in pathologies in which rapid fluctuations of plasma D-glucose may occur and may underlie the reported vasodilatation in early stages of diabetes mellitus.
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Affiliation(s)
- Carlos Flores
- Cellular and Molecular Physiology Laboratory, Department of Physiology, Faculty of Biological Sciences, University of Concepción, Concepción, Chile
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