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Potier L, Mohammedi K, Saulnier PJ, Fumeron F, Halimi JM, Venteclef N, Marre M, Hadjadj S, Roussel R, Velho G. Plasma Adrenomedullin, Allelic Variations in the ADM Gene, and Risk for Lower-Limb Amputation in People With Type 2 Diabetes. Diabetes Care 2022; 45:1631-1639. [PMID: 35583678 DOI: 10.2337/dc21-2638] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Accepted: 04/08/2022] [Indexed: 02/03/2023]
Abstract
OBJECTIVE Patients with diabetes have an increased risk for lower-limb amputation (LLA), but biomarkers to assess risk of LLA are lacking. Adrenomedullin (ADM) is a vasodilator peptide that also plays a role in fluid and electrolyte homeostasis in the kidney, increasing natriuresis and diuresis. ADM was shown to be associated with cardiovascular and renal events in diabetes, but it was not investigated in terms of LLA risk. We investigated the hypothesis that ADM is associated with LLA in people with type 2 diabetes. RESEARCH DESIGN AND METHODS We studied 4,375 participants in the DIABHYCAR and SURDIAGENE cohorts (men, 68%; mean 66 years of age; mean duration of diabetes 12 years; and median follow-up 5.3 years). Plasma midregional proadrenomedullin (MR-proADM; a surrogate for ADM) was measured by immunofluorescence. Five single nucleotide polymorphisms (SNPs) in the ADM gene region were genotyped. RESULTS LLA requirement during follow-up by increasing tertiles of plasma MR-proADM distribution was 1.0% (tertile 1 [T1]), 2.3% (T2), and 4.4% (T3) (P < 0.0001). In Cox multivariate analysis, the adjusted hazard ratio (95% CI) for LLA was 4.40 (2.30-8.88) (P < 0.0001) for T3 versus T1. Moreover, MR-proADM significantly improved indices for risk stratification of LLA. Four SNPs were associated with plasma MR-proADM concentration at baseline and with LLA during follow-up. Alleles associated with higher MR-proADM were associated with increased LLA risk. CONCLUSIONS We observed associations of plasma MR-proADM with LLA and of ADM SNPs with plasma MR-proADM and with LLA in people with type 2 diabetes. This pattern of Mendelian randomization supports the causality of the association of ADM with LLA.
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Affiliation(s)
- Louis Potier
- Institut Necker-Enfants Malades, INSERM, Université de Paris, Paris, France.,Service d'Endocrinologie Diabétologie Nutrition, Hôpital Bichat, Assistance Publique-Hôpitaux de Paris, Paris, France
| | - Kamel Mohammedi
- Bordeaux University and Hospital, INSERM U1034, Bordeaux, France
| | - Pierre-Jean Saulnier
- Centre d'Investigation Clinique CIC 1402, INSERM, Université de Poitiers, CHU Poitiers, Poitiers, France
| | - Frédéric Fumeron
- Institut Necker-Enfants Malades, INSERM, Université de Paris, Paris, France
| | - Jean-Michel Halimi
- CHU de Tours, Service Néphrologie, Dialyse et Transplantation, Tours, France.,INSERM CIC 0202, Tours, France
| | - Nicolas Venteclef
- Institut Necker-Enfants Malades, INSERM, Université de Paris, Paris, France
| | - Michel Marre
- Institut Necker-Enfants Malades, INSERM, Université de Paris, Paris, France.,Clinique Ambroise Paré, Neuilly-sur-Seine, France
| | - Samy Hadjadj
- Institut du Thorax, INSERM, CNRS, Université Nantes, CHU Nantes, Nantes, France
| | - Ronan Roussel
- Institut Necker-Enfants Malades, INSERM, Université de Paris, Paris, France.,Service d'Endocrinologie Diabétologie Nutrition, Hôpital Bichat, Assistance Publique-Hôpitaux de Paris, Paris, France
| | - Gilberto Velho
- Institut Necker-Enfants Malades, INSERM, Université de Paris, Paris, France
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Trevisan CSC, Garcia-Araújo AS, Duarte ACGO, Furino VO, Russo TL, Fujimoto A, Souza HCD, Jaenisch RB, Arena R, Borghi-Silva A. Effects of respiratory muscle training on parasympathetic activity in diabetes mellitus. ACTA ACUST UNITED AC 2021; 54:e10865. [PMID: 34008758 PMCID: PMC8130104 DOI: 10.1590/1414-431x2020e10865] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Accepted: 02/26/2021] [Indexed: 11/21/2022]
Abstract
This study verified the effects of respiratory muscle training (RMT) on hemodynamics, heart rate (HR) variability, and muscle morphology in rats with streptozotocin-induced diabetes mellitus (DM). Thirty-six male Wistar rats were randomized into 4 groups and 34 completed the study: i) sham-sedentary (Sham-ST; n=9); ii) sham-RMT (Sham-RMT; n=9); iii) DM-sedentary (DM-ST; n=8); and iv) DM-RMT (DM-RMT; n=8). Hemodynamics were assessed by central cannulation, and R-R intervals were measured by electrocardiogram. In addition, the effects of RMT on the cross-sectional area of the diaphragm, anterior tibial, and soleus muscles were analyzed. The induction of DM by streptozotocin resulted in weight loss, hyperglycemia, reduced blood pressure, and attenuated left ventricular contraction and relaxation (P<0.05). We also observed a decrease in root mean square of successive differences between adjacent RR intervals (RMSSD) index and in the cross-sectional area of the muscles assessed, specifically the diaphragm, soleus, and anterior tibial muscles in diabetic rats (P<0.05). Interestingly, RMT led to an increase in RMSSD in rats with DM (P<0.05). The induction of DM produced profound deleterious changes in the diaphragmatic and peripheral muscles, as well as impairments in cardiovascular hemodynamics and autonomic control. Nevertheless, RMT may beneficially attenuate autonomic changes and improve parasympathetic modulation.
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Affiliation(s)
- C S C Trevisan
- Departamento de Fisioterapia, Universidade Federal de São Carlos, São Carlos, SP, Brasil
| | - A S Garcia-Araújo
- Departamento de Fisioterapia, Universidade Federal de São Carlos, São Carlos, SP, Brasil
| | - A C G O Duarte
- Departamento de Educação Física e Motricidade Humana, Universidade Federal de São Carlos, São Carlos, SP, Brasil
| | - V O Furino
- Departamento de Educação Física e Motricidade Humana, Universidade Federal de São Carlos, São Carlos, SP, Brasil
| | - T L Russo
- Departamento de Fisioterapia, Universidade Federal de São Carlos, São Carlos, SP, Brasil
| | - A Fujimoto
- Departamento de Fisioterapia, Universidade Federal de São Carlos, São Carlos, SP, Brasil
| | - H C D Souza
- Departamento de Ciências da Saúde, Curso de Fisioterapia, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brasil
| | - R B Jaenisch
- Departamento de Fisioterapia e Reabilitação, Universidade Federal de Santa Maria, Santa Maria, RS, Brasil
| | - R Arena
- Department of Physical Therapy, College of Applied Health Sciences, University of Illinois at Chicago, Chicago, IL, USA
| | - A Borghi-Silva
- Departamento de Fisioterapia, Universidade Federal de São Carlos, São Carlos, SP, Brasil
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Tsuruda T, Kato J, Kuwasako K, Kitamura K. Adrenomedullin: Continuing to explore cardioprotection. Peptides 2019; 111:47-54. [PMID: 29577955 DOI: 10.1016/j.peptides.2018.03.012] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Revised: 03/15/2018] [Accepted: 03/19/2018] [Indexed: 10/17/2022]
Abstract
Adrenomedullin (AM), a peptide isolated from an extract of human pheochromocytoma, comprises 52 amino acids with an intramolecular disulfide bond and amidation at the carboxy-terminus. AM is present in various tissues and organs in rodents and humans, including the heart. The peptide concentration increases with cardiac hypertrophy, acute myocardial infarction, and overt heart failure in the plasma and the myocardium. The principal function of AM in the cardiovascular system is the regulation of the vascular tone by vasodilation and natriuresis via cyclic adenosine monophosphate-dependent or -independent mechanism. In addition, AM may possess unique properties that inhibit aldosterone secretion, oxidative stress, apoptosis, and stimulation of angiogenesis, resulting in the protection of the structure and function of the heart. The AM receptor comprises a complex between calcitonin receptor-like receptor (CLR) and receptor activity-modifying protein (RAMP) 2 or 3, and the AM-CLR/RAMP2 system is essential for heart development during embryogenesis. Small-scale clinical trials have proven the efficacy and safety of recombinant AM peptide therapy for heart failure. Gene delivery and a modified AM peptide that prolongs the half-life of the native peptide could be an innovative method to improve the efficacy and benefit of AM in clinical settings. In this review, we focus on the pathophysiological roles of AM and its receptor system in the heart and describe the advances in AM and proAM-derived peptides as diagnostic biomarkers as well as the therapeutic application of AM and modified AM for cardioprotection.
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Affiliation(s)
- Toshihiro Tsuruda
- Department of Internal Medicine, Circulatory and Body Fluid Regulation, Faculty of Medicine, University of Miyazaki, 5200 Kihara, Kiyotake, Miyazaki 889-1692, Japan.
| | - Johji Kato
- Frontier Science Research Center, Faculty of Medicine, University of Miyazaki, Japan
| | - Kenji Kuwasako
- Frontier Science Research Center, Faculty of Medicine, University of Miyazaki, Japan
| | - Kazuo Kitamura
- Department of Internal Medicine, Circulatory and Body Fluid Regulation, Faculty of Medicine, University of Miyazaki, 5200 Kihara, Kiyotake, Miyazaki 889-1692, Japan
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SIRT-3 Modulation by Resveratrol Improves Mitochondrial Oxidative Phosphorylation in Diabetic Heart through Deacetylation of TFAM. Cells 2018; 7:cells7120235. [PMID: 30487434 PMCID: PMC6315986 DOI: 10.3390/cells7120235] [Citation(s) in RCA: 80] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Revised: 10/08/2018] [Accepted: 10/10/2018] [Indexed: 12/16/2022] Open
Abstract
Background and Purpose: Mitochondrial dysfunction remains the crucial cause for many heart diseases including diabetic cardiomyopathy (DCM). Sirtuin-3 (SIRT-3) is a protein deacetylase localized in the mitochondria and regulates mitochondrial function. Being a noteworthy mitochondrial protein deacetylase enzyme, the role of SIRT-3 in DCM is yet to be explored. Experimental Approach: Diabetes mellitus (Type-I, T1DM) was induced using streptozotocin (STZ, 50 mg/kg) in male Sprague Dawley (SD) rats. Rats with >200 mg/dL blood glucose levels were then divided randomly into two groups, DIA and DIA + RESV, where vehicle and resveratrol (25 mg/kg/day) were administered orally in both groups, respectively. Cardiac oxidative stress, fibrosis, and mitochondrial parameters were evaluated. H9c2 cells were transfected with SIRT-3 siRNA and shRNA, and ORF plasmid for silencing and overexpression, respectively. Key Results: After eight weeks, diabetic rat heart showed reduced cardiac cell size, increased oxidative stress and reduction of the activities of enzymes involved in mitochondrial oxidative phosphorylation (OXPHOS). There was reduced expression and activity of SIRT-3 and mitochondrial transcription factor (TFAM) in diabetic heart. Reduced SIRT-3 expression is also correlated with increased acetylation, decreased mitochondrial DNA (mtDNA) binding activity of TFAM, and reduced transcription of mitochondrial DNA encoded genes. Administration of resveratrol prevented the decrease in SIRT-3 and TFAM activity, which was corresponding to the reduced acetylation status of TFAM. Silencing SIRT-3 using siRNA in H9C2 cells showed increased acetylation of TFAM. Conclusion and Implications: Together our data shows that resveratrol activates SIRT-3, regulates the acetylation status of TFAM and preserves the mitochondrial function along with cellular size in diabetic rat heart.
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Natural and synthetic peptides in the cardiovascular diseases: An update on diagnostic and therapeutic potentials. Arch Biochem Biophys 2018; 662:15-32. [PMID: 30481494 DOI: 10.1016/j.abb.2018.11.021] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2018] [Revised: 10/31/2018] [Accepted: 11/21/2018] [Indexed: 02/07/2023]
Abstract
Several peptides play an important role in physiological and pathological conditions into the cardiovascular system. In addition to well-known vasoactive agents such as angiotensin II, endothelin, serotonin or natriuretic peptides, the vasoconstrictor Urotensin-II (Uro-II) and the vasodilators Urocortins (UCNs) and Adrenomedullin (AM) have been implicated in the control of vascular tone and blood pressure as well as in cardiovascular disease states including congestive heart failure, atherosclerosis, coronary artery disease, and pulmonary and systemic hypertension. Therefore these peptides, together with their receptors, become important therapeutic targets in cardiovascular diseases (CVDs). Circulating levels of these agents in the blood are markedly modified in patients with specific CVDs compared with those in healthy patients, becoming also potential biomarkers for these pathologies. This review will provide an overview of current knowledge about the physiological roles of Uro-II, UCN and AM in the cardiovascular system and their implications in cardiovascular diseases. It will further focus on the structural modifications carried out on original peptide sequences in the search of analogues with improved physiochemical properties as well as in the delivery methods. Finally, we have overviewed the possible application of these peptides and/or their precursors as biomarkers of CVDs.
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Patel VB, Shah S, Verma S, Oudit GY. Epicardial adipose tissue as a metabolic transducer: role in heart failure and coronary artery disease. Heart Fail Rev 2018; 22:889-902. [PMID: 28762019 DOI: 10.1007/s10741-017-9644-1] [Citation(s) in RCA: 137] [Impact Index Per Article: 22.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Obesity and diabetes are strongly associated with metabolic and cardiovascular disorders including dyslipidemia, coronary artery disease, hypertension, and heart failure. Adipose tissue is identified as a complex endocrine organ, which by exerting a wide array of regulatory functions at the cellular, tissue and systemic levels can have profound effects on the cardiovascular system. Different terms including "epicardial," "pericardial," and "paracardial" have been used to describe adipose tissue deposits surrounding the heart. Epicardial adipose tissue (EAT) is a unique and multifaceted fat depot with local and systemic effects. The functional and anatomic proximity of EAT to the myocardium enables endocrine, paracrine, and vasocrine effects on the heart. EAT displays a large secretosome, which regulates physiological and pathophysiological processes in the heart. Perivascular adipose tissue (PVAT) secretes adipose-derived relaxing factor, which is a "cocktail" of cytokines, adipokines, microRNAs, and cellular mediators, with a potent effect on paracrine regulation of vascular tone, vascular smooth muscle cell proliferation, migration, atherosclerosis-susceptibility, and restenosis. Although there are various physiological functions of the EAT and PVAT, a phenotypic transformation can lead to a major pathogenic role in various cardiovascular diseases. The equilibrium between the physiological and pathophysiological properties of EAT is very delicate and susceptible to the influences of intrinsic and extrinsic factors. Various adipokines secreted from EAT and PVAT have a profound effect on the myocardium and coronary arteries; targeting these adipokines could be an important therapeutic approach to counteract cardiovascular disease.
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Affiliation(s)
- Vaibhav B Patel
- Division of Cardiology, Department of Medicine, University of Alberta, Edmonton, AB, T6G 2S2, Canada
- Mazankowski Alberta Heart Institute, University of Alberta, Edmonton, Canada
- Department of Physiology and Pharmacology and Libin Cardiovascular Institute of Alberta, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Saumya Shah
- Division of Cardiology, Department of Medicine, University of Alberta, Edmonton, AB, T6G 2S2, Canada
- Mazankowski Alberta Heart Institute, University of Alberta, Edmonton, Canada
| | - Subodh Verma
- Division of Cardiac Surgery, Keenan Research Centre for Biomedical Science, St. Michael's Hospital, Toronto, ON, Canada
- Department of Surgery, University of Toronto, Toronto, ON, Canada
- Institute of Medical Science, University of Toronto, Toronto, ON, Canada
| | - Gavin Y Oudit
- Division of Cardiology, Department of Medicine, University of Alberta, Edmonton, AB, T6G 2S2, Canada.
- Mazankowski Alberta Heart Institute, University of Alberta, Edmonton, Canada.
- Department of Physiology, University of Alberta, Edmonton, Canada.
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Chodari L, Mohammadi M, Mohaddes G, Alipour MR, Ghorbanzade V, Dariushnejad H, Mohammadi S. Testosterone and Voluntary Exercise, Alone or Together Increase Cardiac Activation of AKT and ERK1/2 in Diabetic Rats. Arq Bras Cardiol 2016; 107:532-541. [PMID: 28558078 PMCID: PMC5210457 DOI: 10.5935/abc.20160174] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2016] [Accepted: 08/04/2016] [Indexed: 01/03/2023] Open
Abstract
Background Impaired angiogenesis in cardiac tissue is a major complication of diabetes.
Protein kinase B (AKT) and extracellular signal regulated kinase (ERK)
signaling pathways play important role during capillary-like network
formation in angiogenesis process. Objectives To determine the effects of testosterone and voluntary exercise on levels of
vascularity, phosphorylated Akt (P- AKT) and phosphorylated ERK (P-ERK) in
heart tissue of diabetic and castrated diabetic rats. Methods Type I diabetes was induced by i.p injection of 50 mg/kg of streptozotocin in
animals. After 42 days of treatment with testosterone (2mg/kg/day) or
voluntary exercise alone or in combination, heart tissue samples were
collected and used for histological evaluation and determination of P-AKT
and P-ERK levels by ELISA method. Results Our results showed that either testosterone or exercise increased
capillarity, P-AKT, and P-ERK levels in the heart of diabetic rats.
Treatment of diabetic rats with testosterone and exercise had a synergistic
effect on capillarity, P-AKT, and P-ERK levels in heart. Furthermore, in the
castrated diabetes group, capillarity, P-AKT, and P-ERK levels significantly
decreased in the heart, whereas either testosterone treatment or exercise
training reversed these effects. Also, simultaneous treatment of castrated
diabetic rats with testosterone and exercise had an additive effect on P-AKT
and P-ERK levels. Conclusion Our findings suggest that testosterone and exercise alone or together can
increase angiogenesis in the heart of diabetic and castrated diabetic rats.
The proangiogenesis effects of testosterone and exercise are associated with
the enhanced activation of AKT and ERK1/2 in heart tissue.
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Affiliation(s)
- Leila Chodari
- Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Mustafa Mohammadi
- Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Gisou Mohaddes
- Neuroscience Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | | | - Vajiheh Ghorbanzade
- Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Hassan Dariushnejad
- Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Shima Mohammadi
- Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
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Adrenomedullin Promotes the Proliferation and Inhibits Apoptosis of Dental Pulp Stem Cells Involved in Divergence Pathways. J Endod 2016; 42:1347-54. [DOI: 10.1016/j.joen.2016.06.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2015] [Revised: 05/26/2016] [Accepted: 06/03/2016] [Indexed: 12/14/2022]
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Eichler TE, Becknell B, Easterling RS, Ingraham SE, Cohen DM, Schwaderer AL, Hains DS, Li B, Cohen A, Metheny J, Tridandapani S, Spencer JD. Insulin and the phosphatidylinositol 3-kinase signaling pathway regulate Ribonuclease 7 expression in the human urinary tract. Kidney Int 2016; 90:568-79. [PMID: 27401534 DOI: 10.1016/j.kint.2016.04.025] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2016] [Revised: 04/12/2016] [Accepted: 04/28/2016] [Indexed: 10/21/2022]
Abstract
Diabetes mellitus is a systemic disease associated with a deficiency of insulin production or action. Diabetic patients have an increased susceptibility to infection with the urinary tract being the most common site. Recent studies suggest that Ribonuclease 7 (RNase 7) is a potent antimicrobial peptide that plays an important role in protecting the urinary tract from bacterial insult. Because the impact of diabetes on RNase 7 expression and function are unknown, we investigated the effects of insulin on RNase 7 using human urine specimens. The urinary RNase 7 concentrations were measured in healthy control patients and insulin-deficient type 1 diabetics before and after starting insulin therapy. Compared with controls, diabetic patients had suppressed urinary RNase 7 concentrations, which increased with insulin. Using primary human urothelial cells, the mechanisms by which insulin stimulates RNase 7 synthesis were next explored. Insulin induced RNase 7 production via the phosphatidylinositide 3-kinase signaling pathway (PI3K/AKT) to shield urothelial cells from uropathogenic E. coli. In contrast, uropathogenic E. coli suppressed PI3K/AKT activity and RNase 7 production. Thus, insulin and PI3K/AKT signaling are essential for RNase 7 expression and increased infection risks in diabetic patients may be secondary to suppressed RNase 7 production. Our data may provide unique insight into novel urinary tract infection therapeutic strategies in at-risk populations.
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Affiliation(s)
- Tad E Eichler
- Center for Clinical and Translational Research, Department of Pediatrics, The Research Institute at Nationwide Children's, Columbus, Ohio, USA
| | - Brian Becknell
- Center for Clinical and Translational Research, Department of Pediatrics, The Research Institute at Nationwide Children's, Columbus, Ohio, USA; Division of Nephrology, Department of Pediatrics, Nationwide Children's, Columbus, Ohio, USA
| | - Robert S Easterling
- Center for Clinical and Translational Research, Department of Pediatrics, The Research Institute at Nationwide Children's, Columbus, Ohio, USA; University of Toledo College of Medicine and Life Sciences, Toledo, Ohio, USA
| | - Susan E Ingraham
- Center for Clinical and Translational Research, Department of Pediatrics, The Research Institute at Nationwide Children's, Columbus, Ohio, USA; Division of Nephrology, Department of Pediatrics, Nationwide Children's, Columbus, Ohio, USA
| | - Daniel M Cohen
- Division of Emergency Medicine, Department of Pediatrics, Nationwide Children's, Columbus, Ohio, USA
| | - Andrew L Schwaderer
- Center for Clinical and Translational Research, Department of Pediatrics, The Research Institute at Nationwide Children's, Columbus, Ohio, USA; Division of Nephrology, Department of Pediatrics, Nationwide Children's, Columbus, Ohio, USA
| | - David S Hains
- Innate Immunity Translational Research Center, Department of Pediatrics, Children's Foundation Research Institute at Le Bonheur Children's Hospital, Memphis, Tennessee, USA
| | - Birong Li
- Center for Clinical and Translational Research, Department of Pediatrics, The Research Institute at Nationwide Children's, Columbus, Ohio, USA
| | - Ariel Cohen
- Center for Clinical and Translational Research, Department of Pediatrics, The Research Institute at Nationwide Children's, Columbus, Ohio, USA
| | - Jackie Metheny
- Center for Clinical and Translational Research, Department of Pediatrics, The Research Institute at Nationwide Children's, Columbus, Ohio, USA
| | - Susheela Tridandapani
- Department of Internal Medicine, Comprehensive Cancer Center, The Ohio State University James Cancer Hospital and Richard J. Solove Research Institute, Columbus, Ohio, USA; Department of Molecular Virology, Immunology, and Medical Genetics, Comprehensive Cancer Center, The Ohio State University James Cancer Hospital and Richard J. Solove Research Institute, Columbus, Ohio, USA
| | - John David Spencer
- Center for Clinical and Translational Research, Department of Pediatrics, The Research Institute at Nationwide Children's, Columbus, Ohio, USA; Division of Nephrology, Department of Pediatrics, Nationwide Children's, Columbus, Ohio, USA.
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Microbubbles and Ultrasound: Therapeutic Applications in Diabetic Nephropathy. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016; 880:309-30. [PMID: 26486345 DOI: 10.1007/978-3-319-22536-4_17] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Diabetic nephropathy (DN) remains one of the most common causes of end-stage renal disease. Current therapeutic strategies aiming at optimization of serum glucose and blood pressure are beneficial in early stage DN, but are unable to fully prevent disease progression. With the limitations of current medical therapies and the shortage of available donor organs for kidney transplantation, the need for novel therapies to address DN complications and prevent progression towards end-stage renal failure is crucial. The development of ultrasound technology for non-invasive and targeted in-vivo gene delivery using high power ultrasound and carrier microbubbles offers great therapeutic potential for the prevention and treatment of DN. The promising results from preclinical studies of ultrasound-mediated gene delivery (UMGD) in several DN animal models suggest that UMGD offers a unique, non-invasive platform for gene- and cell-based therapies targeted against DN with strong clinical translation potential.
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11
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Velho G, Ragot S, Mohammedi K, Gand E, Fraty M, Fumeron F, Saulnier PJ, Bellili-Munoz N, Bouby N, Potier L, Alhenc-Gelas F, Marre M, Hadjadj S, Roussel R. Plasma Adrenomedullin and Allelic Variation in the ADM Gene and Kidney Disease in People With Type 2 Diabetes. Diabetes 2015; 64:3262-72. [PMID: 25948679 DOI: 10.2337/db14-1852] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/04/2014] [Accepted: 04/30/2015] [Indexed: 11/13/2022]
Abstract
Production of adrenomedullin (ADM), a vasodilator peptide, increases in response to ischemia and hypoxia in the vascular wall and the kidney. This may be an adaptive response providing protection against organ damage. We investigated the hypothesis that ADM has a nephroprotective effect in two prospective cohorts of patients with type 2 diabetes recruited in France. The highest tertile of plasma MR-proADM (a surrogate for ADM) concentration at baseline was associated with the risk of renal outcomes (doubling of plasma creatinine concentration and/or progression to end-stage renal disease) during follow-up in both cohorts. Four SNPs in the ADM gene region were associated with plasma MR-proADM concentration at baseline and with eGFR during follow-up in both cohorts. The alleles associated with lower eGFR were also associated with lower plasma MR-proADM level. In conclusion, plasma MR-proADM concentration was associated with renal outcome in patients with type 2 diabetes. Our data suggest that the ADM gene modulates the genetic susceptibility to nephropathy progression. Results are consistent with the hypothesis of a reactive rise of ADM in diabetic nephropathy, blunted in risk alleles carriers, and with a nephroprotective effect of ADM. A possible therapeutic effect of ADM receptor agonists in diabetic renal disease would be worth investigating.
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Affiliation(s)
- Gilberto Velho
- INSERM, UMR_S 1138, Centre de Recherche des Cordeliers, Paris, France
| | - Stéphanie Ragot
- INSERM, Centre d'Investigation Clinique (CIC) 1402, Poitiers, France UFR de Médecine et Pharmacie, Université de Poitiers, Poitiers, France
| | - Kamel Mohammedi
- INSERM, UMR_S 1138, Centre de Recherche des Cordeliers, Paris, France Assistance Publique - Hôpitaux de Paris, Department of Diabetology, Endocrinology and Nutrition, Bichat Hospital, DHU FIRE, Paris, France
| | - Elise Gand
- Department of Endocrinology and Diabetology, Centre Hospitalier Universitaire de Poitiers, Poitiers, France
| | - Mathilde Fraty
- INSERM, Centre d'Investigation Clinique (CIC) 1402, Poitiers, France
| | - Frédéric Fumeron
- INSERM, UMR_S 1138, Centre de Recherche des Cordeliers, Paris, France UFR de Médecine, Université Paris Diderot, Sorbonne Paris Cité, Paris, France
| | - Pierre-Jean Saulnier
- INSERM, Centre d'Investigation Clinique (CIC) 1402, Poitiers, France UFR de Médecine et Pharmacie, Université de Poitiers, Poitiers, France INSERM, Research Unit 1082, Poitiers, France
| | | | - Nadine Bouby
- INSERM, UMR_S 1138, Centre de Recherche des Cordeliers, Paris, France Sorbonne Universités, UPMC Univ Paris 06, UMR_S 1138, Centre de Recherche des Cordeliers, Paris, France Université Paris Descartes, Sorbonne Paris Cité, UMR_S 1138, Centre de Recherche des Cordeliers, Paris, France
| | - Louis Potier
- INSERM, UMR_S 1138, Centre de Recherche des Cordeliers, Paris, France Assistance Publique - Hôpitaux de Paris, Department of Diabetology, Endocrinology and Nutrition, Bichat Hospital, DHU FIRE, Paris, France UFR de Médecine, Université Paris Diderot, Sorbonne Paris Cité, Paris, France
| | - François Alhenc-Gelas
- INSERM, UMR_S 1138, Centre de Recherche des Cordeliers, Paris, France Sorbonne Universités, UPMC Univ Paris 06, UMR_S 1138, Centre de Recherche des Cordeliers, Paris, France Université Paris Descartes, Sorbonne Paris Cité, UMR_S 1138, Centre de Recherche des Cordeliers, Paris, France
| | - Michel Marre
- INSERM, UMR_S 1138, Centre de Recherche des Cordeliers, Paris, France Assistance Publique - Hôpitaux de Paris, Department of Diabetology, Endocrinology and Nutrition, Bichat Hospital, DHU FIRE, Paris, France UFR de Médecine, Université Paris Diderot, Sorbonne Paris Cité, Paris, France
| | - Samy Hadjadj
- INSERM, Centre d'Investigation Clinique (CIC) 1402, Poitiers, France UFR de Médecine et Pharmacie, Université de Poitiers, Poitiers, France Department of Endocrinology and Diabetology, Centre Hospitalier Universitaire de Poitiers, Poitiers, France INSERM, Research Unit 1082, Poitiers, France
| | - Ronan Roussel
- INSERM, UMR_S 1138, Centre de Recherche des Cordeliers, Paris, France Assistance Publique - Hôpitaux de Paris, Department of Diabetology, Endocrinology and Nutrition, Bichat Hospital, DHU FIRE, Paris, France UFR de Médecine, Université Paris Diderot, Sorbonne Paris Cité, Paris, France
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12
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Effect of Piper sarmentosum Extract on the Cardiovascular System of Diabetic Sprague-Dawley Rats: Electron Microscopic Study. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2012; 2012:628750. [PMID: 23304208 PMCID: PMC3523161 DOI: 10.1155/2012/628750] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/11/2012] [Accepted: 11/15/2012] [Indexed: 11/17/2022]
Abstract
Although Piper sarmentosum (PS) is known to possess the antidiabetic properties, its efficacy towards diabetic cardiovascular tissues is still obscured. The present study aimed to observe the electron microscopic changes on the cardiac tissue and proximal aorta of experimental rats treated with PS extract. Thirty-two male Sprague-Dawley rats were divided into four groups: untreated control group (C), PS-treated control group (CTx), untreated diabetic group (D), and PS-treated diabetic group (DTx). Intramuscular injection of streptozotocin (STZ, 50 mg/kg body weight) was given to induce diabetes. Following 28 days of diabetes induction, PS extract (0.125 g/kg body weight) was administered orally for 28 days. Body weight, fasting blood glucose, and urine glucose levels were measured at 4-week interval. At the end of the study, cardiac tissues and the aorta were viewed under transmission electron microscope (TEM). DTx group showed increase in body weight and decrease in fasting blood glucose and urine glucose level compared to the D group. Under TEM study, DTx group showed lesser ultrastructural degenerative changes in the cardiac tissues and the proximal aorta compared to the D group. The results indicate that PS restores ultrastructural integrity in the diabetic cardiovascular tissues.
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13
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Alteration of purinergic neurotransmission in isolated atria of streptozotocin-induced diabetic rats. J Cardiovasc Pharmacol 2012; 59:158-64. [PMID: 21983745 DOI: 10.1097/fjc.0b013e31823a0f31] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Cardiac dysfunctions are described in diabetes. However, the role of purinergic neurotransmission in diabetes-related cardiovascular diseases is unknown. The purpose of this study was to evaluate the purinergic neurotransmission in isolated atria from streptozotocin-induced diabetic rats. The animals were grouped as control and diabetic with 30 days (D30) and 60 days (D60) after streptozotocin-induced diabetes. The isolated left and right atria were used in functional experiments. The effects of adenosine triphosphate, uridine diphosphate, and adenosine were evaluated on atrial inotropism and chronotropism. The antagonists 8-cyclopentyl-1,3-dipropylxanthine and pyridoxal-phosphate-6-azophenyl-2',4'-disulfonate were also used, as blockers of P1 and P2 receptors, respectively. A negative inotropic effect followed by a positive inotropic effect was induced by adenosine triphosphate in isolated atria. This negative inotropic effect was decreased by 25% in left atria of D30. Additionally, the apparent affinity for adenosine was diminished in left atria of D30, suggesting changes in P1 receptor function. No changes were found in the right atria of D30 stimulated by adenosine. The left atria and right atria stimulated by uridine diphosphate showed an increased inotropic effect of 92% and 17%, respectively. No changes were observed in left and right atria of D30 stimulated by uridine diphosphate. Our data showed the involvement of purinergic neurotransmission in diabetes-related cardiovascular changes.
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14
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Jacob A, Wu R, Wang P. Regulation of RAMP expression in diseases. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2012; 744:87-103. [PMID: 22434110 DOI: 10.1007/978-1-4614-2364-5_8] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Receptor-activity modifying proteins (RAMPs) belong to a single family of transmembrane proteins. RAMPs determine ligand specificity of G-protein coupled receptors; calcitonin receptor and the calcitonin-receptor like receptor (CLR). To date, three members of RAMP family (RAMP-1, -2, -3) have been identified. The co-expression of RAMP-1 with CLR constitutes the calcitonin gene related peptide receptor whereas the association of the RAMP-2 or RAMP-3 with CLR forms the adrenomedullin (AM) receptor. Alterations in signaling and subcellular distribution of G-protein coupled receptors can be responsible for the regulation of many disease conditions. These changes may be mediated by the different isoforms of RAMPs associated with such receptors. In this chapter, we describe the differential responses associated with upregulation of RAMPs in disease conditions. For instance, the upregulation of all three RAMP isoforms contributes to the cardioprotective effects of the CLR/RAMP ligands. On the other hand, strong evidence exists for the involvement of AM in various cancers and that its action is mediated by the upregulation of RAMP isoforms, RAMP-2 and -3. Though limited, a few studies have been reported on the differential response associated with the upregulation of RAMP in other disease conditions such as sepsis, liver cirrhosis, glomerulonephritis, Type 1 diabetes and Parkinson's disease. Thus, the regulation of RAMP expression is involved in the pathophysiology associated with various diseases.
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Affiliation(s)
- Asha Jacob
- The Feinstein Institute of Medical Research, Manhasset, NY, USA
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15
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Kuwasako K, Kitamura K, Nagata S, Hikosaka T, Takei Y, Kato J. Shared and separate functions of the RAMP-based adrenomedullin receptors. Peptides 2011; 32:1540-50. [PMID: 21645567 DOI: 10.1016/j.peptides.2011.05.022] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/11/2011] [Revised: 05/20/2011] [Accepted: 05/20/2011] [Indexed: 11/25/2022]
Abstract
Adrenomedullin (AM) is a novel hypotensive peptide that exerts a variety of strongly protective effects against multiorgan damage. AM-specific receptors were first identified as heterodimers composed of calcitonin-receptor-like receptor (CLR), a G protein coupled receptor, and one of two receptor activity-modifying proteins (RAMP2 or RAMP3), which are accessory proteins containing a single transmembrane domain. RAMPs are required for the surface delivery of CLR and the determination of its phenotype. CLR/RAMP2 (AM₁ receptor) is more highly AM-specific than CLR/RAMP3 (AM₂ receptor). Although there have been no reports showing differences in intracellular signaling via the two AM receptors, in vitro studies have shed light on their distinct trafficking and functionality. In addition, the tissue distributions of RAMP2 and RAMP3 differ, and their gene expression is differentially altered under pathophysiological conditions, which is suggestive of the separate roles played by AM₁ and AM₂ receptors in vivo. Both AM and the AM₁ receptor, but not the AM₂ receptor, are crucial for the development of the fetal cardiovascular system and are able to effectively protect against various vascular diseases. However, AM₂ receptors reportedly play an important role in maintaining a normal body weight in old age and may be involved in immune function. In this review article, we focus on the shared and separate functions of the AM receptor subtypes and also discuss the potential for related drug discovery. In addition, we mention their possible function as receptors for AM2 (or intermedin), an AM-related peptide whose biological functions are similar to those of AM.
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Affiliation(s)
- Kenji Kuwasako
- Frontier Science Research Center, University of Miyazaki, 5200 Kihara, Kiyotake, Miyazaki, Miyazaki 889-1692, Japan.
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16
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Zhang J, Zhang BH, Yu YR, Tang CS, Qi YF. Adrenomedullin protects against fructose-induced insulin resistance and myocardial hypertrophy in rats. Peptides 2011; 32:1415-21. [PMID: 21664393 DOI: 10.1016/j.peptides.2011.05.024] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/30/2011] [Revised: 05/25/2011] [Accepted: 05/25/2011] [Indexed: 01/13/2023]
Abstract
Adrenomedullin (ADM) has been recognized as a multipotent multifunctional peptide. To explore the pathophysiological roles of ADM in insulin resistance (IR), we studied the changes in ADM mRNA level in the myocardium and vessels and the effect of ADM supplementation on rats with IR induced by fructose feeding. Rats were fed 4% fructose in drinking water for 8 weeks, and ADM was administered subcutaneously in pure water through an Alzet Mini-osmotic Pump at 300 ng/kg/h for the last 4 weeks. Compared with controls, rats with IR showed increased levels of fasting blood sugar and serum insulin, by 95% and 67%, respectively (all P<0.01), and glycogen synthesis and glucose transport activity of the soleus decreased by 54% and 55% (all P<0.01). mRNA level and content of brain natriuretic peptide (BNP) in myocardial were all increased significantly. Fructose-fed rats showed increased immunoreactive-ADM content in plasma by 110% and in myocardia by 55% and increased mRNA level in myocardia and vessels (all P<0.01). ADM administration ameliorated the induced IR and myocardial hypertrophy. The glycogen synthesis and glucose transport activity of the soleus muscle increased by 41% (P<0.01) and 32% (P<0.05). ADM therapy attenuated myocardial and soleus lipid peroxidation injury and enhanced the antioxidant ability. Our results showed upregulation of endogenous ADM during fructose-induced IR and the protective effect of ADM on fructose-induced IR and concomitant cardiovascular hypertrophy probably by its antioxidant effect, which suggests that ADM could be an endogenous protective factor in IR.
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Affiliation(s)
- Jing Zhang
- School of P.E. and Sports Science, Beijing Normal University, Beijing 100875, China
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17
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Anigbogu CN, Williams DT, Brown DR, Silcox DL, Speakman RO, Brown LC, Karounos DG, Randall DC. Circadian Variations in Blood Pressure, Heart Rate, and HR-BP Cross-Correlation Coefficient during Progression of Diabetes Mellitus in Rat. Int J Hypertens 2011; 2011:738689. [PMID: 21629872 PMCID: PMC3095977 DOI: 10.4061/2011/738689] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2011] [Accepted: 02/10/2011] [Indexed: 11/20/2022] Open
Abstract
Circadian changes in cardiovascular function during the progression of diabetes mellitus in the diabetes prone rat (BBDP) (n = 8) were studied. Age-matched diabetes-resistant rats (BBDR) served as controls. BP was recorded via telemetry in contiguous 4 hr time periods over 24 hours starting with 12 midnight to 4 am as period zero (P0). Prior to onset of diabetes BP was high at P0, peaked at P2, and then fell again at P3; BP and heart rate (HR) then increased gradually at P4 and leveled off at P5, thereby exhibiting a bipodal rhythm. These patterns changed during long-term diabetes. The cross-correlation coefficient of BP and HR was not significantly different across groups at onset, but it fell significantly at 9 months of duration of diabetes (BBDP: 0.39 ± 0.06; BBDR: 0.65 ± 0.03; P < .05). These results show that changes in circadian cardiovascular rhythms in diabetes mellitus became significant at the late stage of the disease.
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Affiliation(s)
- Chikodi N. Anigbogu
- Department of Physiology, College of Medicine, University of Lagos, 12003 Lagos, Nigeria
- Department of Physiology, College of Medicine University of Kentucky, Lexington, KY 40536-0298, USA
| | - Daniel T. Williams
- Department of Physiology, College of Medicine University of Kentucky, Lexington, KY 40536-0298, USA
| | - David R. Brown
- Department of Physiology, College of Medicine University of Kentucky, Lexington, KY 40536-0298, USA
| | - Dennis L. Silcox
- Department of Physiology, College of Medicine University of Kentucky, Lexington, KY 40536-0298, USA
| | - Richard O. Speakman
- Department of Physiology, College of Medicine University of Kentucky, Lexington, KY 40536-0298, USA
| | - Laura C. Brown
- Department of Physiology, College of Medicine University of Kentucky, Lexington, KY 40536-0298, USA
| | - Dennis G. Karounos
- Lexington VA Medical Center and Department of Internal Medicine, College of Medicine University of Kentucky, Lexington, KY 40536-0298, USA
| | - David C. Randall
- Department of Physiology, College of Medicine University of Kentucky, Lexington, KY 40536-0298, USA
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Henein HY, Younan SM, Rashed LA, Fakhry A. Effect of adrenomedullin gene delivery on insulin resistance in type 2 diabetic rats. J Adv Res 2011. [DOI: 10.1016/j.jare.2010.08.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
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19
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Vinagre AS, Rönnau ÂDRO, Pereira SF, Silveira LUD, Wiilland EDF, Suyenaga ES. Anti-diabetic effects of Campomanesia xanthocarpa (Berg) leaf decoction. BRAZ J PHARM SCI 2010. [DOI: 10.1590/s1984-82502010000200002] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The objective of this research was to identify the effects of 3-week treatment of normal and streptozotocin-induced diabetic rats using a leaf decoction of Campomanesia xanthocarpa Berg. (20 g/L) on physiological, biochemical and histological parameters. Streptozotocin (STZ, 70 mg/kg in citrate buffer, pH 4.5) was administered IP to induce experimental diabetes one week prior to the treatment. STZ caused typical diabetic symptoms: polydypsia, polyuria, polyphagia, hyperglycemia, hypertriglyceridemia and histopathological modifications in the pancreas, liver and kidney. The treatment of diabetic rats using the decoction decreased blood glucose levels, inhibited hepatic glycogen loss, and prevented potential histopathological alterations in the pancreas and kidneys. No differences were found between the control rats treated with the decoction and the control rats maintained on water only. In conclusion, these results suggest that C. xanthocarpa leaf decoction (20g/L) might be useful for diabetes mellitus management, but further pharmacological and toxicological studies are needed.
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Kobayashi T, Taguchi K, Nemoto S, Nogami T, Matsumoto T, Kamata K. Activation of the PDK-1/Akt/eNOS pathway involved in aortic endothelial function differs between hyperinsulinemic and insulin-deficient diabetic rats. Am J Physiol Heart Circ Physiol 2009; 297:H1767-75. [PMID: 19717727 DOI: 10.1152/ajpheart.00536.2009] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
In diabetic states, altered plasma insulin is likely to play key roles in 3-phosphoinositide-dependent protein kinase (PDK)/Akt pathway activation, in insulin resistance and in endothelial dysfunction. Since the molecular mechanism(s) remains unclear, we examined the relationship between the PDK/Akt/endothelial nitric oxide synthase (NOS) pathway and endothelial function in aortas from diabetic rats that were either insulin deficient or hyperinsulinemic. Untreated diabetic (diabetic) rats exhibited hyperglycemia and hypoinsulinemia, whereas high-insulin-treated diabetic (HI-diabetic) rats exhibited hyperinsulinemia. Aortas from the diabetic group displayed impaired endothelium-dependent relaxation in response to ACh, whereas the insulin-induced relaxation was increased. In HI-diabetic aortas, the ACh-induced relaxation was normal, but that induced by insulin was impaired. The insulin-induced relaxation was inhibited by treatment with an Akt inhibitor in control and diabetic aortas, but not in the HI-diabetic aorta. This inhibitory effect on insulin-induced relaxation was greater in diabetic aortas than in control aortas. In all groups, ACh-induced relaxation was unaffected by the above inhibitor. In the diabetic group, various insulin-stimulated levels (nitric oxide production, phosphorylation of endothelial NOS at Ser(1177), of Akt at Thr(308), and of PDK-1 at Ser(241)) were significantly increased, whereas, in the HI-diabetic group, these levels were all decreased (vs. control aortas). These results suggest that the plasma insulin level has a close relation to the level of aortic PDK-1/Akt (at Thr(308))/NOS activities, and that reduced actions of the PDK-1/Akt (at Thr(308)) signal pathway may contribute to the impairments of insulin-induced endothelial functions seen in hyperinsulinemic diabetes.
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Affiliation(s)
- Tsuneo Kobayashi
- Department of Physiology and Morphology, Institute of Medicinal Chemistry, Hoshi University, Tokyo, Japan
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21
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Wang T, Hou LB, Liu ZJ, Wang Y, Chen CL, Xiao X, Wang DW. Intramuscular delivery of rAAV-mediated kallikrein gene reduces hypertension and prevents cardiovascular injuries in model rats. Acta Pharmacol Sin 2007; 28:1898-906. [PMID: 18031602 DOI: 10.1111/j.1745-7254.2007.00677.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
AIM The overexpression of the human tissue kallikrein (HK) gene can reduce blood pressure and ameliorate the secondary syndromes associated with hypertension in animal models. The current study was designed to investigate hypotensive effect of intramuscular delivery of HK gene. METHODS We generated an recombinant adeno-associated virus (rAAV) vector expressing human tissue kallikrein under the control of a cytomegalovirus promoter and administered the rAAV-HK vector to a spontaneously hypertensive rat model at a dose of 1 x 10(10) virons/rat through intramuscular injection. RESULTS A persistent, high-level expression of HK post-gene delivery was confirmed by ELISA. The systolic blood pressure in the rats receiving rAAV-LacZ and saline increased from 171.3 mmHg to 182.3 mmHg 28 weeks' post injection. In contrast, the delivery of the HK gene by AAV vectors attenuated the increase of the systolic blood pressure in the treated group. The systolic blood pressure was only slightly lowered (from a level of 174 mmHg to 170.5 mmHg) post-vector administration. The difference in blood pressure between the treated group and the control groups is statistically significant at 12.6 mmHg. The hypotensive effect of rAAV-HK persisted until the end of the testing period. In addition, a significant amelioration of cardiovascular hypertrophy, renal injury, and collagen depositions in the rAAV-HK-treated animals were also observed. CONCLUSION All the effects are comparable with those of intravenous delivery. Therefore, the intramuscular administration of rAAV-HK may be used in gene therapy for hypertension.
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Affiliation(s)
- Tao Wang
- Institute of Hypertension and Department of Internal Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
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Wang XF, Shao Y, Chen SW, Tian DZ, Huang GY, Huang Y, Yao T, Lu LM. AMELIORATION OF CARDIAC FUNCTION IN CHRONIC MYOCARDIAL INFARCTED RATS FOLLOWING ADMINISTRATION OF VECTOR pcDNA3.1AM. Clin Exp Pharmacol Physiol 2007; 34:861-5. [PMID: 17645630 DOI: 10.1111/j.1440-1681.2007.04678.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
1. The present study was designed to examine the cardiovascular effects of intravenously administered pcDNA3.1AM, a recombinant non-virus vector carrying a rat adrenomedullin (AM) gene translation fragment, in rats with chronic cardiac dysfunction induced by ligation of the left descending coronary artery. 2. Haemodynamic parameters were recorded by intraventricular catheterization. In situ hybridization and polymerase chain reaction (PCR) were performed to identify the distribution of the introduced vector. The concentration of AM was determined by radioimmunoassay. 3. Progressive cardiac dysfunction was observed following coronary artery ligation, as indicated by a significant reduction in mean arterial pressure (MAP) and increases in both central venous pressure (CVP) and end-diastolic pressure of the left ventricle (LVEDP; P < 0.01). Administration of pcDNA3.1AM significantly attenuated the progressive cardiac dysfunction and lowered the elevated CVP and LVEDP. The introduced vector was widely distributed in different organs, including the lungs, kidney, heart, liver, spleen and brain. However, intense staining of pcDNA3.1 AM was observed in the lungs and kidneys. The introduced vector was localized mainly in the endothelial cells of blood vessels. Radioimmunoassay showed elevated levels of AM in the plasma and lung and heart after surgery, but there was no significant further increase in the concentration of AM after pcDNA3.1AM delivery. 4. The present study has provided some novel findings on the potential beneficial effects of AM gene delivery on chronic cardiac function in rats. Expression of AM by a non-virus vector may also have therapeutic value against cardiac dysfunction in vivo.
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Affiliation(s)
- Xiao-Fang Wang
- Department of Physiology and Pathophysiology, Shanghai Medical College, Fudan University, Shanghai, China
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23
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Wichi R, Malfitano C, Rosa K, De Souza SB, Salemi V, Mostarda C, De Angelis K, Irigoyen MC. Noninvasive and invasive evaluation of cardiac dysfunction in experimental diabetes in rodents. Cardiovasc Diabetol 2007; 6:14. [PMID: 17462095 PMCID: PMC1866223 DOI: 10.1186/1475-2840-6-14] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/03/2007] [Accepted: 04/26/2007] [Indexed: 01/08/2023] Open
Abstract
Background Because cardiomyopathy is the leading cause of death in diabetic patients, the determination of myocardial function in diabetes mellitus is essential. In the present study, we provide an integrated approach, using noninvasive echocardiography and invasive hemodynamics to assess early changes in myocardial function of diabetic rats. Methods Diabetes was induced by streptozotocin injection (STZ, 50 mg/kg). After 30 days, echocardiography (noninvasive) at rest and invasive left ventricular (LV) cannulation at rest, during and after volume overload, were performed in diabetic (D, N = 7) and control rats (C, N = 7). The Student t test was performed to compare metabolic and echocardiographic differences between groups at 30 days. ANOVA was used to compare LV invasive measurements, followed by the Student-Newman-Keuls test. Differences were considered significant at P < 0.05 for all tests. Results Diabetes impaired LV systolic function expressed by reduced fractional shortening, ejection fraction, and velocity of circumferential fiber shortening compared with that in the control group. The diabetic LV diastolic dysfunction was evidenced by diminished E-waves and increased A-waves and isovolumic relaxation time. The myocardial performance index was greater in diabetic compared with control rats, indicating impairment in diastolic and systolic function. The LV systolic pressure was reduced and the LV end-diastolic pressure was increased at rest in diabetic rats. The volume overload increased LVEDP in both groups, while LVEDP remained increased after volume overload only in diabetic rats. Conclusion These results suggest that STZ-diabetes induces systolic and diastolic dysfunction at rest, and reduces the capacity for cardiac adjustment to volume overload. In addition, it was also demonstrated that rodent echocardiography can be a useful, clinically relevant tool for the study of initial diabetic cardiomyopathy manifestations in asymptomatic patients.
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Affiliation(s)
- Rogério Wichi
- Hypertension Unit, Heart Institute (INCOR), University of São Paulo, Medical School, São Paulo, Brazil
- São Judas Tadeu University, Human Movement Laboratory, São Paulo, Brazil
| | - Christiane Malfitano
- Hypertension Unit, Heart Institute (INCOR), University of São Paulo, Medical School, São Paulo, Brazil
- Nephrology Department, Federal University of São Paulo, São Paulo, Brazil
| | - Kaleizu Rosa
- Hypertension Unit, Heart Institute (INCOR), University of São Paulo, Medical School, São Paulo, Brazil
- Experimental Pathophysiology Program, University of São Paulo, Medical School, São Paulo, Brazil
| | - Silvia B De Souza
- Hypertension Unit, Heart Institute (INCOR), University of São Paulo, Medical School, São Paulo, Brazil
- Nephrology Department, Federal University of São Paulo, São Paulo, Brazil
| | - Vera Salemi
- Cardiomyopathies Unit, Heart Institute (INCOR), University of São Paulo, Medical School, São Paulo, Brazil
| | - Cristiano Mostarda
- Hypertension Unit, Heart Institute (INCOR), University of São Paulo, Medical School, São Paulo, Brazil
- Nephrology Department, Federal University of São Paulo, São Paulo, Brazil
| | - Kátia De Angelis
- Hypertension Unit, Heart Institute (INCOR), University of São Paulo, Medical School, São Paulo, Brazil
- São Judas Tadeu University, Human Movement Laboratory, São Paulo, Brazil
| | - Maria Claudia Irigoyen
- Hypertension Unit, Heart Institute (INCOR), University of São Paulo, Medical School, São Paulo, Brazil
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Hwang ISS, Tang F, Leung PP, Li YY, Fan ST, Luk JMC. The gene expression of adrenomedullin, calcitonin-receptor-like receptor and receptor activity modifying proteins (RAMPs) in CCl4-induced rat liver cirrhosis. ACTA ACUST UNITED AC 2006; 135:69-77. [PMID: 16713642 DOI: 10.1016/j.regpep.2006.04.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2006] [Revised: 04/04/2006] [Accepted: 04/09/2006] [Indexed: 12/13/2022]
Abstract
This study was undertaken to determine AM expression in carbon tetrachloride (CCl4)-induced liver cirrhosis developed with peritoneal ascites. Sprague-Dawley rats received subcutaneous injections of CCl4 twice weekly in olive oil (1:1, 0.3 ml per kg body weight) for 6 or 12 weeks until ascites developed, or saline in olive oil as control. At 6 weeks, fibrosis developed and at 12 weeks cirrhosis developed with ascites formation. At both 6 and 12 weeks, increases in plasma renin and AM were evident, as was the gene expression of AM. At 12 weeks after CCl4 injection, the gene expression of calcitonin-like-receptor (CRLR) and receptor activity modifying proteins (RAMP1, RAMP2 and RAMP3) were all elevated when compared to the control. The results suggest that liver cirrhosis increases mRNA expressions of AM, CRLR and RAMP1, RAMP2 and RAMP3 and that the increase in AM gene expression precedes the development of cirrhosis. The increase in AM synthesis as reflected by an increase in AM gene expression, together with a lack of increase in AM peptide at both 6 and 12 weeks may suggest an elevation of AM release. Given the potent vasodilatory action of AM, the increase in the synthesis and release of AM in the cirrhotic liver may also contribute to peripheral vasodilatation in liver cirrhosis.
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Affiliation(s)
- Isabel Shui Shan Hwang
- Center for the Study of Liver Disease, The University of Hong Kong, Pokfulam, Hong Kong, China
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25
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Iwatsubo S, Fujimoto S, Matsumoto M, Sato Y, Hara S, Kitamura K, Eto T. Increased Production of Adrenomedullin in Glomeruli from Anti-Glomerular Basement Membrane Glomerulonephritis Rats Treated with Methylprednisolone. ACTA ACUST UNITED AC 2006; 104:e41-7. [PMID: 16735801 DOI: 10.1159/000093675] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2005] [Accepted: 03/06/2006] [Indexed: 12/26/2022]
Abstract
BACKGROUND/AIMS Adrenomedullin (AM) has anti-proliferative and apoptotic effects on mesangial cells (MCs). Both effects play an important role in the progression of glomerulonephritis (GN). Glucocorticoids are widely used for the treatment of GN; however, the relationship between AM regulation in MCs or glomeruli and glucocorticoid treatment has not been clarified. METHODS Using the cultured rat MCs, AM secretion induced by methylprednisolone (m-PSL), and MC proliferation and apoptosis caused by AM were examined. In addition, the role of AM receptor antagonist, AM(22-52), was also investigated. Then, we made an anti-glomerular basement membrane (GBM) GN rat model and compared the AM expression and production in each glomeruli obtained from the control or m-PSL-treated anti-GBM GN rats. RESULTS In the cultured rat MCs, AM secretion was increased by m-PSL. MC proliferation was inhibited, while MC apoptosis was increased by AM. MC apoptosis was inhibited by the addition of AM(22-52). M-PSL therapy ameliorated the progression of anti-GBM GN rats. AM expression and production were increased in the glomeruli from m-PSL-treated rats compared to the controls. CONCLUSION Considering the anti-proliferative and apoptotic effects of AM on MCs, increased AM in the glomeruli might participate in the improvement of glomerular lesions in anti-GBM GN rats treated with m-PSL.
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Affiliation(s)
- Shuji Iwatsubo
- First Department of Internal Medicine, Miyazaki Medical College, University of Miyazaki, Miyazaki, Japan
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Chen L, Kis B, Busija DW, Yamashita H, Ueta Y. Adrenomedullin protects rat cerebral endothelial cells from oxidant damage in vitro. ACTA ACUST UNITED AC 2005; 130:27-34. [PMID: 15913808 DOI: 10.1016/j.regpep.2005.03.006] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2004] [Revised: 02/05/2005] [Accepted: 03/02/2005] [Indexed: 11/26/2022]
Abstract
Increased permeability and reduced cerebral endothelial cell (CEC) viability induced by oxidative stress are the hallmarks of the blood-brain barrier disruption. In our experiments hydrogen peroxide (H2O2, 0.5 mM) induced a continuous decrease of the transendothelial electrical resistance (TEER) and resulted in intercellular gap formations in cultured rat CECs. Adrenomedullin (AM) increased TEER, enhanced peripheral localization of F-actin bands and attenuated the increased permeability induced by H2O2. Furthermore, AM treatment preserved mitochondrial membrane potential, attenuated cytochrome c release, and consequently improved CEC viability in H2O2 treated cultures. These results suggest that AM treatment protects CECs against oxidative injury.
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Affiliation(s)
- Lei Chen
- Department of Physiology, School of Medicine, University of Occupational and Environmental Health, Iseigaoka 1-1, Yahatanishi-ku, Kitakyushu 807-8555, Japan
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Fujisawa Y, Nagai Y, Miyatake A, Takei Y, Miura K, Shoukouji T, Nishiyama A, Kimura S, Abe Y. Renal effects of a new member of adrenomedullin family, adrenomedullin2, in rats. Eur J Pharmacol 2005; 497:75-80. [PMID: 15321737 DOI: 10.1016/j.ejphar.2004.06.039] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2004] [Revised: 06/18/2004] [Accepted: 06/22/2004] [Indexed: 11/15/2022]
Abstract
A new member of the adrenomedullin family, adrenomedullin2, was identified in mammals. The effects of adrenomedullin2 on renal hemodynamics and urine formation were examined in rats. Intrarenal arterial infusion of adrenomedullin2 at rates of 30, 100 and 300 pmol/kg/min decreased blood pressure and increased heart rate in a dose-dependent fashion. Adrenomedullin2 infusion at 100 pmol/kg/min significantly increased renal blood flow and urine flow. At the higher infusion rate (300 pmol/kg/min), adrenomedullin2 significantly decreased urine flow. Continuous intrarenal infusion of adrenomedullin2 at 100 pmol/kg/min significantly increased renal blood flow from 6.7+/-0.5 to 8.8+/-0.5 ml/min and decreased renal vascular resistance from 16+/-1 to 11+/-1 mm Hg min/ml. Urine flow was significantly increased from 21.5+/-4.9 to 36.2+/-8.5 microl/min and urinary excretion of sodium was increased from 2.3+/-0.9 to 4.9+/-1.4 microEq/min. Blood pressure, heart rate and glomerular filtration rate did not change. Infusion of a similar dose of adrenomedullin also increased renal blood flow (6.8+/-0.4-8.8+/-0.6 ml/min), urine flow (25.4+/-3.2-42.8+/-9.4 microl/min) and urinary excretion of sodium (2.8+/-0.6-6.5+/-1.2 microEq/min), decreased renal vascular resistance (15+/-1-11+/-1 mm Hg min/ml) and did not alter glomerular filtration rate. Thus, the renal actions induced by adrenomedullin2 were similar to those of adrenomedullin. These data suggest that adrenomedullin2 may play an important role in the regulation of renal hemodynamics and urine formation.
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Affiliation(s)
- Yoshihide Fujisawa
- Research Equipment Center, School of medicine, Kagawa University, 1750-1 Ikenobe, Miki-cho, Kita-gun, Kagawa 761-0793, Japan.
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Chen SW, Wang XF, Shao Y, Xue H, Zhou L, Yao T, Lu LM. Similar effects on rat renal mesangial cells by expressing different fragments of adrenomedullin gene in vitro. Acta Pharmacol Sin 2005; 26:845-50. [PMID: 15960892 DOI: 10.1111/j.1745-7254.2005.00138.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
AIM To construct pEGFP-N3 recombinant vectors carrying adrenomedullin (AM) or fragments of the AM gene, and to express AM or fragments of AM from the pEGFP-N3 recombinant vectors (pEGFP-N3-AM1-2 and pEGFP-N3-AM1-3) and study their biological properties on cultured rat renal mesangial cells (RMC). METHODS Total RNA of rat kidney was obtained using TriZol reagent. The cDNA was synthesized by reverse transcriptase using oligo-deoxythymidine as primer. The fragments of AM gene were then amplified by polymerase chain reaction (PCR) with specific upstream and downstream oligonucleotides. The PCR products were digested with EcoRI and BamHI and subcloned into the plasmid pEGFP-N3. Facilitated by cationic liposomes, RMC were transfected with pEGFP-N3-AM1-2 or pEGFP-N3-AM1-3. After 24 h, green fluorescent protein (GFP) fluorescent images were examined with a fluorescence microscope. After 48 h, the proliferation of RMC was detected using the MTT assay, and the mRNA expression of transforming growth factor-beta1 (TGF-beta1) was measured by semiquantitative PCR. RESULTS DNA sequence reports verified that pEGFP-N3-AM1-2, which carried the full length AM gene translation fragment (preproadrenomedullin preproAM1-185), and pEGFP-N3-AM1-3, which carried the translation fragment of preproAM [without adrenotensin (ADT, preproAM150-185)], were constructed successfully. After 24 h, green fluorescence was observed in RMC into which either pEGFP-N3-AM1-2 or pEGFP-N3-AM1-3 was transfected, while in the control cells no fluorescence was observed. Either pEGFP-N3-AM1-2 or pEGFP-N3-AM1-3 delivery inhibited the proliferation of RMC (P<0.01) and decreased the mRNA transcription level of TGF-beta1 in RMC (P<0.05). However, no significant difference was observed between the effects of pEGFP-N3-AM1-2 and pEGFP-N3-AM1-3. CONCLUSION pEGFP-N3-AM1-2 and pEGFP-N3-AM1-3 were constructed successfully and were functionally expressed in RMC. Expressing the fragment of AM without ADT has similar inhibitory biological effects on RMS proliferation and TGF-beta1 transcription with full length preproAM.
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Affiliation(s)
- Shao-Wei Chen
- Department of Physiology and Pathophysiology, Shanghai Medical College, Fudan University, Shanghai 200032, China
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Kuo MC, Kuo HT, Chiu YW, Chang JM, Guh JY, Lai YH, Chen HC. Decreased synthesis of glomerular adrenomedullin in patients with IgA nephropathy. ACTA ACUST UNITED AC 2005; 145:233-8. [PMID: 15902095 DOI: 10.1016/j.lab.2005.02.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Adrenomedullin (AM) immunostaining and gene expression have seldom been measured in human kidneys. Because previous studies have shown that AM exerts antiproliferative effects on rat mesangial cells in vitro and that urine AM levels are decreased in patients with chronic glomerulonephritis, we measured glomerular AM and its gene expression in patients with primary IgA nephropathy (IgAN). Glomerular AM was measured by immunohistochemical staining, and glomerular AM mRNA was measured by in situ hybridization. Plasma and urine AM were measured by radioimmunoassay. The results showed that both the intensity of immunostaining for glomerular AM and the glomerular expression of AM mRNA were significantly decreased in IgAN patients compared with normal controls (both P < .05). Similar results were not observed in patients with non-IgA MsPGN. Glomerular AM immunostaining and glomerular AM mRNA expression were significantly correlated ( P < .001), and both were negatively correlated with the number of glomerular cells ( P < .05 and < .01, respectively). Both glomerular AM immunostaining and glomerular AM mRNA expression were correlated with urine AM levels (both P < .001), but not with plasma AM levels. The urine AM level was significantly lower in IgAN patients than in normal controls ( P < .01), whereas the plasma level was not different between the 2 groups. Our findings indicate that glomerular production of AM was decreased in patients with IgA nephropathy and that this lack of glomerular AM may be related to the pathogenesis of this mesangial disease.
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Affiliation(s)
- Mei-Chuan Kuo
- Division of Nephrology, Department of Internal Medicine, Kaohsiung Medical University, Taiwan, Republic of China
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Christou H, Bailey N, Kluger MS, Mitsialis SA, Kourembanas S. Extracellular acidosis induces heme oxygenase-1 expression in vascular smooth muscle cells. Am J Physiol Heart Circ Physiol 2005; 288:H2647-52. [PMID: 15681695 DOI: 10.1152/ajpheart.00937.2004] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Extracellular acidosis (EA) has profound effects on vascular homeostasis, including vascular bed-specific alterations in vascular tone. Regulation of gene expression by EA has been observed in a variety of cells including vascular endothelial cells. Whether EA regulates gene expression in vascular smooth muscle cells (VSMCs) is not known. Heme oxygenase (HO)-1 is expressed in vascular cells, and its expression is regulated by cellular stressors such as heat, radiation, and hypoxia. Increased HO-1 expression in VSMCs leads to increased production of CO and its second messenger cGMP, which are important regulators of vascular tone and paracrine interactions in the vasculature. We examined whether EA regulates the expression of HO-1 in VSMCs. Exposure of VSMCs to acidic medium (pH 6.8) significantly increased HO-1 mRNA and protein compared with exposure to medium of physiological pH (pH 7.4). The acidic induction of HO-1 expression was time dependent and involved both transcriptional activation of the HO-1 gene and enhanced stability of HO-1 mRNA. Nitric oxide did not appear to mediate this response. We conclude that HO-1 is transcriptionally and posttranscriptionally upregulated by EA in VSMCs. This induction is time dependent and reversible. We speculate that EA, as an important tissue and cellular stressor for VSMCs, may elicit changes in gene expression patterns that contribute to the maintenance or disruption of vascular homeostasis.
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Affiliation(s)
- Helen Christou
- Div. of Newborn Medicine, Children's Hospital, 300 Longwood Ave., Enders 9, Boston, MA 02115, USA.
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Kobayashi T, Matsumoto T, Kamata K. The PI3-K/Akt pathway: roles related to alterations in vasomotor responses in diabetic models. J Smooth Muscle Res 2005; 41:283-302. [PMID: 16557003 DOI: 10.1540/jsmr.41.283] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Macro- and microvascular disease states currently represent the principal causes of morbidity and mortality in patients with type I or type II diabetes mellitus. Abnormal vasomotor responses and impaired endothelium-dependent vasodilation have been demonstrated in various beds in different animal models of diabetes and in humans with type I or type II diabetes. Several mechanisms leading to endothelial dysfunction have been reported, including changes in substrate avail ability, impaired release of NO, and increased destruction of NO. The principal mediators of diabetes-associated endothelial dysfunction are (a) increases in oxidized low density lipoprotein, endothelin-1, angiotensin II, oxidative stress, and (b) decreases in the actions of insulin or growth factors in endothelial cells. An accumulating body of evidence indicates that abnormal regulation of the phosphatidylinositol 3-kinase (PI3-K)/Akt pathway may be one of several factors contributing to vascular dysfunction in diabetes. The PI3-K pathway, which activates serine/threonine protein kinase Akt, enhances NO synthase phosphorylation and NO production. Several studies suggest that in diabetes the relative ineffectiveness of insulin and the hyperglycemia act together to reduce activity in the insulin-receptor substrates (IRS)/PI3-K/Akt pathway, resulting in impairments of both IRS/PI3-K/Akt-mediated endothelial function and NO production. This article summarizes the PI3-K/Akt pathway-mediated contraction and relaxation responses induced by various agents in the blood vessels of diabetic animals.
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Affiliation(s)
- Tsuneo Kobayashi
- Department of Physiology and Morphology, Institute of Medicinal Chemistry, Hoshi University, Tokyo, Japan.
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Xia CF, Yin H, Borlongan CV, Chao J, Chao L. Adrenomedullin Gene Delivery Protects Against Cerebral Ischemic Injury by Promoting Astrocyte Migration and Survival. Hum Gene Ther 2004; 15:1243-54. [PMID: 15684700 DOI: 10.1089/hum.2004.15.1243] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Adrenomedullin (AM) has been shown to protect against ischemia/reperfusion-induced myocardial infarction and apoptosis. In the present study, we examined the potential neuroprotective action of delayed AM gene transfer in cerebral ischemia. Three days after a 1-hr occlusion of the middle cerebral artery (MCAO), rats were injected intravenously with adenovirus harboring human AM cDNA. The experiment was terminated 7 days after MCAO. AM gene transfer significantly reduced cerebral infarct size compared with that of rats before virus injection and compared with that of rats injected with control virus. The expression of recombinant human AM was identified in ischemic brain by immunostaining. Morphological analyses showed that AM gene transfer enhanced the survival and migration of astrocytes into the ischemic core. Cerebral ischemia markedly increased astrocyte apoptosis, and AM gene delivery significantly reduced apoptosis to near normal levels as seen in sham control rats. Similarly, in primary cultured astrocytes, AM stimulated cell migration and inhibited hypoxia/reoxygenation-induced apoptosis. The effects of AM on both migration and apoptosis were abolished by calcitonin gene-related peptide [CGRP(8-37)], an AM receptor antagonist. Enhanced cell survival after AM gene transfer was accompanied by markedly increased cerebral nitric oxide and Bcl-2 levels, as well as Akt and GSK-3beta phosphorylation, but reduced NADPH oxidase activity and superoxide production. Inactivation of GSK-3beta by phosphorylation led to reduced GSK-3beta activity and caspase- 3 activation. These results indicate that exogenous AM provides neuroprotection against cerebral ischemia injury by enhancing astrocyte survival and migration and inhibiting apoptosis through suppression of oxidative stress-mediated signaling events.
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Affiliation(s)
- Chun-Fang Xia
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, SC 29425, USA
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Muff R, Born W, Lutz TA, Fischer JA. Biological importance of the peptides of the calcitonin family as revealed by disruption and transfer of corresponding genes. Peptides 2004; 25:2027-38. [PMID: 15501537 DOI: 10.1016/j.peptides.2004.08.007] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/11/2004] [Accepted: 08/11/2004] [Indexed: 10/26/2022]
Abstract
The hormone calcitonin (CT) of thyroid C-cell origin, the neuropeptides alpha- and beta-calcitonin gene-related peptide (CGRP), the widely expressed hormone and tissue factor adrenomedullin (AM), and amylin (AMY) that is co-produced with insulin in pancreatic beta-cells, are structurally related peptides. They have in common six or seven amino acid ring structures, linked by disulfide bridges between cysteine residues, and amidated carboxyl termini that are both required for biological activity. The actions of the peptides in vivo have traditionally been studied after intravenous and intracerebroventricular administration. As a result, CT lowers serum calcium and reduces pain perception. alpha- and beta CGRP and AM are highly potent vasodilatory peptides. AMY inhibits food intake through its action in the area postrema of the brain. Physiological actions of the peptides summarized in the present review have been defined through gene knockout and overexpression strategies.
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Affiliation(s)
- Roman Muff
- Department of Orthopedic Surgery, Research Laboratory for Calcium Metabolism, University of Zurich, Balgrist University Hospital, Forchstrasse 340, 8008 Zurich, Switzerland.
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Ruzicska E, Foldes G, Lako-Futo Z, Sarman B, Wellmann J, Szenasi G, Tulassay Z, Ruskoaho H, Toth M, Somogyi A. Cardiac gene expression of natriuretic substances is altered in streptozotocin-induced diabetes during angiotensin II-induced pressure overload. J Hypertens 2004; 22:1191-200. [PMID: 15167455 DOI: 10.1097/00004872-200406000-00021] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE To gain insight into the cardiac adaptive mechanisms in diabetes, we studied whether angiotensin II (Ang II) alters expression of the atrial natriuretic peptide (ANP), B-type natriuretic peptide (BNP) and adrenomedullin (AM) genes in the left ventricle of the diabetic rat heart. METHODS Diabetes was induced by streptozotocin (STZ; 60 mg/kg body weight intravenously). During the last 24 h of 2.5 or 7 weeks of treatment of male Wistar rats with STZ or vehicle, Ang II (33 microg/kg per h) was administered via osmotic minipumps. RESULTS Diabetes was associated with an increased left ventricular weight to body weight (LV/BW) ratio, an index of left ventricular hypertrophy, at week 7 but not at week 2.5, and with increased ANP mRNA content at 2.5 weeks, but not with altered expression of the AM and BNP genes. Mean arterial pressure and LV/BW ratio were increased by Ang II in all groups except in the 7-week diabetic group. Levels of ANP mRNA were increased fourfold (P < 0.001) and threefold (P < 0.05) by Ang II at 2.5 and 7 weeks in control animals, respectively, and 11-fold (P < 0.001) and sevenfold (P < 0.001) at 2.5 and 7 weeks in diabetic animals, respectively. Ang II increased ventricular concentrations of BNP mRNA in control and diabetic animals at 2.5 weeks (1.3-fold, P < 0.001; and 1.6-fold, P < 0.001) and at 7 weeks (1.3-fold, P < 0.05; and 1.8-fold, P < 0.001), respectively. Left ventricular levels of adrenomedullin mRNA were increased by treatment with Ang II for 24 h in 2.5-week diabetic animals. CONCLUSION Ang II markedly increased the levels of natriuretic peptide mRNAs in the left ventricle of normal and diabetic rat hearts, whereas it increased adrenomedullin mRNA levels only in 2.5-week diabetic rats and failed to cause hypertension in 7-week diabetic rats. Left ventricular levels of ANP and BNP mRNA were increased by Ang II in diabetic animals more than the additive effects of diabetes and Ang II alone, showing that Ang II induced an amplified response with respect to cardiac concentrations of ANP and BNP in diabetes.
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Affiliation(s)
- Eva Ruzicska
- 2nd Department of Internal Medicine, Semmelweis University, Budapest, Hungary.
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White SM, Constantin PE, Claycomb WC. Cardiac physiology at the cellular level: use of cultured HL-1 cardiomyocytes for studies of cardiac muscle cell structure and function. Am J Physiol Heart Circ Physiol 2004; 286:H823-9. [PMID: 14766671 DOI: 10.1152/ajpheart.00986.2003] [Citation(s) in RCA: 296] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
HL-1 cells are currently the only cardiomyocyte cell line available that continuously divides and spontaneously contracts while maintaining a differentiated cardiac phenotype. Extensive characterization using microscopic, genetic, immunohistochemical, electrophysiological, and pharmacological techniques has demonstrated how similar HL-1 cells are to primary cardiomyocytes. In the few years that HL-1 cells have been available, they have been used in a variety of model systems designed to answer important questions regarding cardiac biology at the cellular and molecular levels. Whereas HL-1 cells have been used to study normal cardiomyocyte function with regard to signaling, electrical, metabolic, and transcriptional regulation, they have also been used to address pathological conditions such as hypoxia, hyperglycemia-hyperinsulinemia, apoptosis, and ischemia-reperfusion. The availability of an immortalized, contractile cardiac cell line has provided investigators with a tool for probing the intricacies of cardiomyocyte function. In this review, we describe the culture and characterization of HL-1 cardiomyocytes as well as various model systems that have been developed using these cells to gain a better understanding of cardiac biology at the cellular and molecular levels.
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Affiliation(s)
- Steven M White
- Dept. of Biochemistry and Molecular Biology, Louisiana State Univ. Health Sciences Center, 1901 Perdido St., New Orleans, LA 70112, USA
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Yin H, Chao L, Chao J. Adrenomedullin Protects Against Myocardial Apoptosis After Ischemia/Reperfusion Through Activation of Akt-GSK Signaling. Hypertension 2004; 43:109-16. [PMID: 14662648 DOI: 10.1161/01.hyp.0000103696.60047.55] [Citation(s) in RCA: 100] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Adrenomedullin (AM) is a potent vasoactive peptide and plays an important role in cardiovascular function. In this study, we delivered the AM gene locally into the heart, using a catheter-based technique to investigate the signaling mechanism mediated by AM in protection against cardiomyocyte apoptosis induced by acute ischemia/reperfusion. After adenovirus-mediated gene delivery, highly efficient and specific expression of luciferase, green fluorescent protein, or recombinant human AM was identified in the left ventricle. Delivery of the AM gene 5 days before ischemia/reperfusion attenuated myocardial apoptosis identified by in situ dUTP nick-end labeling and DNA laddering, and the effect was blocked by the AM antagonist human calcitonin gene–related peptide (CGRP 8 to 37). AM gene transfer increased phosphorylation of Akt and glycogen synthase kinase (GSK-3β) but reduced GSK-3β and caspase-3 activities in the heart. The effects of AM on GSK-3β and caspase-3 activities were blocked by CGRP (8-37) and by adenovirus containing dominant-negative Akt (DN-Akt). Furthermore, in cultured cardiomyocytes, AM also attenuated apoptosis induced by hypoxia/reoxygenation, which was accompanied by increased phospho-GSK-3β but reduced GSK-3 and caspase-3 activities. GSK-3 and caspase-3 activities were both blocked by Ad.DN-Akt and lithium, whereas only caspase-3 was inhibited by its inhibitor Z-VAD. The effects of AM on anti-apoptosis and promoting cell viability were blocked by DN-Akt but not by constitutively active Akt, lithium, or Z-VAD. These results indicate that AM protects against cardiomyocyte apoptosis induced by ischemia/reperfusion injury through the Akt-GSK-caspase signaling pathway.
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Affiliation(s)
- Hang Yin
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, SC 29425-2211, USA
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Kato K, Yin H, Agata J, Yoshida H, Chao L, Chao J. Adrenomedullin gene delivery attenuates myocardial infarction and apoptosis after ischemia and reperfusion. Am J Physiol Heart Circ Physiol 2003; 285:H1506-14. [PMID: 12805025 DOI: 10.1152/ajpheart.00270.2003] [Citation(s) in RCA: 90] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Adrenomedullin (AM) has been shown to protect against cardiac remodeling. In this study, we investigated the potential role of AM in myocardial ischemia-reperfusion (I/R) injury through adenovirus-mediated gene delivery. One week after AM gene delivery, rats were subjected to 30-min coronary occlusion, followed by 2-h reperfusion. AM gene transfer significantly reduced the ratio of infarct size to ischemic area at risk and the occurrence of sustained ventricular fibrillation compared with control rats. AM gene delivery also attenuated apoptosis, assessed by both terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling assay and DNA laddering. The effect of AM gene transfer on infarct size, arrhythmia, and apoptosis was abolished by an AM antagonist, calcitonin gene-related peptide [CGRP(8-37)]. Expression of human AM significantly increased cardiac cGMP levels and reduced superoxide production, superoxide density, NAD(P)H oxidase activity, p38 MAPK activation, and Bax levels. Moreover, AM increased Akt and Bad phosphorylation and Bcl-2 levels, but decreased caspase-3 activation. These results indicate that AM protects against myocardial infarction, arrhythmia, and apoptosis in I/R injury via suppression of oxidative stress-induced Bax and p38 MAPK phosphorylation and activation of the Akt-Bad-Bcl-2 signaling pathway. Successful application of this technology may have a protective effect in coronary artery diseases.
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Affiliation(s)
- Kazuo Kato
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, SC 29425-2211, USA
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