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Zhang C, He X, Murphy SR, Zhang H, Wang S, Ge Y, Gao W, Williams JM, Geurts AM, Roman RJ, Fan F. Knockout of Dual-Specificity Protein Phosphatase 5 Protects Against Hypertension-Induced Renal Injury. J Pharmacol Exp Ther 2019; 370:206-217. [PMID: 31118214 PMCID: PMC6636243 DOI: 10.1124/jpet.119.258954] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Accepted: 05/16/2019] [Indexed: 12/28/2022] Open
Abstract
Dual-specificity protein phosphatase 5 (DUSP5) is a member of the tyrosine-threonine phosphatase family with the ability to dephosphorylate and inactivate extracellular signal-related kinase (ERK). The present study investigates whether knockout (KO) of Dusp5 improves renal hemodynamics and protects against hypertension-induced renal injury. The renal expression of DUSP5 was reduced, and the levels of phosphorylated (p) ERK1/2 and p-protein kinase C (PKC) α were elevated in the KO rats. KO of Dusp5 enhanced the myogenic tone of the renal afferent arteriole and interlobular artery in vitro with or without induction of deoxycorticosterone acetate-salt hypertension. Inhibition of ERK1/2 and PKC diminished the myogenic response to a greater extent in Dusp5 KO rats. Autoregulation of renal blood flow was significantly impaired in hypertensive wild-type (WT) rats but remained intact in Dusp5 KO animals. Proteinuria was markedly decreased in hypertensive KO versus WT rats. The degree of glomerular injury was reduced, and the expression of nephrin in the glomerulus was higher in hypertensive Dusp5 KO rats. Renal fibrosis and medullary protein cast formation were attenuated in hypertensive Dusp5 KO rats in association with decreased expression of monocyte chemoattractant protein 1, transforming growth factor-β1, matrix metalloproteinase (MMP) 2, and MMP9. These results indicate that KO of Dusp5 protects against hypertension-induced renal injury, at least in part, by maintaining the myogenic tone of the renal vasculature and extending the range of renal blood flow autoregulation to higher pressures, which diminish glomerular injury, protein cast formation, macrophage infiltration, and epithelial-mesenchymal transformation in the kidney. SIGNIFICANCE STATEMENT: Dual-specificity protein phosphatase 5 (DUSP5) is a tyrosine-threonine phosphatase that inactivates extracellular signal-related kinase (ERK). We previously reported that knockout (KO) of Dusp5 enhanced the myogenic response and autoregulation in the cerebral circulation. The present study investigates whether KO of DUSP5 improves renal hemodynamics and protects against hypertension-induced renal injury. Downregulation of DUSP5 enhanced the myogenic tone of renal arteriole and artery and autoregulation of renal blood flow in association with reduced proteinuria, glomerular injury, and interstitial fibrosis after the induction of hypertension. Inhibition of ERK1/2 and protein kinase C diminished the myogenic response to a greater extent in Dusp5 KO rats. These results suggest that DUSP5 might be a viable drug target for the treatment of hypertension nephropathy.
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Affiliation(s)
- Chao Zhang
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center. Jackson, Mississippi (C.Z., X.H., S.R.M., H.Z., S.W., Y.G., W.G., J.M.W., R.J.R., F.F.); Department of Urology, Zhongshan Hospital, Fudan University. Shanghai, China (C.Z., W.G.); and Department of Physiology, Medical College of Wisconsin. Milwaukee, Wisconsin (A.M.G.)
| | - Xiaochen He
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center. Jackson, Mississippi (C.Z., X.H., S.R.M., H.Z., S.W., Y.G., W.G., J.M.W., R.J.R., F.F.); Department of Urology, Zhongshan Hospital, Fudan University. Shanghai, China (C.Z., W.G.); and Department of Physiology, Medical College of Wisconsin. Milwaukee, Wisconsin (A.M.G.)
| | - Sydney R Murphy
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center. Jackson, Mississippi (C.Z., X.H., S.R.M., H.Z., S.W., Y.G., W.G., J.M.W., R.J.R., F.F.); Department of Urology, Zhongshan Hospital, Fudan University. Shanghai, China (C.Z., W.G.); and Department of Physiology, Medical College of Wisconsin. Milwaukee, Wisconsin (A.M.G.)
| | - Huawei Zhang
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center. Jackson, Mississippi (C.Z., X.H., S.R.M., H.Z., S.W., Y.G., W.G., J.M.W., R.J.R., F.F.); Department of Urology, Zhongshan Hospital, Fudan University. Shanghai, China (C.Z., W.G.); and Department of Physiology, Medical College of Wisconsin. Milwaukee, Wisconsin (A.M.G.)
| | - Shaoxun Wang
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center. Jackson, Mississippi (C.Z., X.H., S.R.M., H.Z., S.W., Y.G., W.G., J.M.W., R.J.R., F.F.); Department of Urology, Zhongshan Hospital, Fudan University. Shanghai, China (C.Z., W.G.); and Department of Physiology, Medical College of Wisconsin. Milwaukee, Wisconsin (A.M.G.)
| | - Ying Ge
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center. Jackson, Mississippi (C.Z., X.H., S.R.M., H.Z., S.W., Y.G., W.G., J.M.W., R.J.R., F.F.); Department of Urology, Zhongshan Hospital, Fudan University. Shanghai, China (C.Z., W.G.); and Department of Physiology, Medical College of Wisconsin. Milwaukee, Wisconsin (A.M.G.)
| | - Wenjun Gao
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center. Jackson, Mississippi (C.Z., X.H., S.R.M., H.Z., S.W., Y.G., W.G., J.M.W., R.J.R., F.F.); Department of Urology, Zhongshan Hospital, Fudan University. Shanghai, China (C.Z., W.G.); and Department of Physiology, Medical College of Wisconsin. Milwaukee, Wisconsin (A.M.G.)
| | - Jan M Williams
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center. Jackson, Mississippi (C.Z., X.H., S.R.M., H.Z., S.W., Y.G., W.G., J.M.W., R.J.R., F.F.); Department of Urology, Zhongshan Hospital, Fudan University. Shanghai, China (C.Z., W.G.); and Department of Physiology, Medical College of Wisconsin. Milwaukee, Wisconsin (A.M.G.)
| | - Aron M Geurts
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center. Jackson, Mississippi (C.Z., X.H., S.R.M., H.Z., S.W., Y.G., W.G., J.M.W., R.J.R., F.F.); Department of Urology, Zhongshan Hospital, Fudan University. Shanghai, China (C.Z., W.G.); and Department of Physiology, Medical College of Wisconsin. Milwaukee, Wisconsin (A.M.G.)
| | - Richard J Roman
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center. Jackson, Mississippi (C.Z., X.H., S.R.M., H.Z., S.W., Y.G., W.G., J.M.W., R.J.R., F.F.); Department of Urology, Zhongshan Hospital, Fudan University. Shanghai, China (C.Z., W.G.); and Department of Physiology, Medical College of Wisconsin. Milwaukee, Wisconsin (A.M.G.)
| | - Fan Fan
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center. Jackson, Mississippi (C.Z., X.H., S.R.M., H.Z., S.W., Y.G., W.G., J.M.W., R.J.R., F.F.); Department of Urology, Zhongshan Hospital, Fudan University. Shanghai, China (C.Z., W.G.); and Department of Physiology, Medical College of Wisconsin. Milwaukee, Wisconsin (A.M.G.)
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Tan JTM, Prosser HCG, Dunn LL, Vanags LZ, Ridiandries A, Tsatralis T, Lecce L, Clayton ZE, Yuen SCG, Robertson S, Lam YT, Celermajer DS, Ng MKC, Bursill CA. High-Density Lipoproteins Rescue Diabetes-Impaired Angiogenesis via Scavenger Receptor Class B Type I. Diabetes 2016; 65:3091-103. [PMID: 27284113 DOI: 10.2337/db15-1668] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/08/2015] [Accepted: 05/18/2016] [Indexed: 11/13/2022]
Abstract
Disordered neovascularization and impaired wound healing are important contributors to diabetic vascular complications. We recently showed that high-density lipoproteins (HDLs) enhance ischemia-mediated neovascularization, and mounting evidence suggests HDL have antidiabetic properties. We therefore hypothesized that HDL rescue diabetes-impaired neovascularization. Streptozotocin-induced diabetic mice had reduced blood flow recovery and neovessel formation in a hindlimb ischemia model compared with nondiabetic mice. Reconstituted HDL (rHDL) infusions in diabetic mice restored blood flow recovery and capillary density to nondiabetic levels. Topical rHDL application rescued diabetes-impaired wound closure, wound angiogenesis, and capillary density. In vitro, rHDL increased key mediators involved in hypoxia-inducible factor-1α (HIF-1α) stabilization, including the phosphoinositide 3-kinase/Akt pathway, Siah1, and Siah2, and suppressed the prolyl hydroxylases (PHD) 2 and PHD3. rHDL rescued high glucose-induced impairment of tubulogenesis and vascular endothelial growth factor (VEGF) A protein production, a finding associated with enhanced phosphorylation of proangiogenic mediators VEGF receptor 2 and endothelial nitric oxide synthase. Siah1/2 small interfering RNA knockdown confirmed the importance of HIF-1α stability in mediating rHDL action. Lentiviral short hairpin RNA knockdown of scavenger receptor class B type I (SR-BI) in vitro and SR-BI(-/-) diabetic mice in vivo attenuated rHDL rescue of diabetes-impaired angiogenesis, indicating a key role for SR-BI. These findings provide a greater understanding of the vascular biological effects of HDL, with potential therapeutic implications for diabetic vascular complications.
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MESH Headings
- Animals
- Blood Glucose/drug effects
- Cell Line
- Cholesterol/blood
- Cholesterol, HDL/blood
- Cholesterol, LDL/blood
- Diabetes Mellitus, Experimental
- Disease Models, Animal
- Humans
- Immunohistochemistry
- Lipoproteins, HDL/blood
- Lipoproteins, HDL/therapeutic use
- Male
- Mice
- Mice, Inbred C57BL
- Neovascularization, Physiologic/drug effects
- Nuclear Proteins/genetics
- Nuclear Proteins/metabolism
- Regional Blood Flow/drug effects
- Regional Blood Flow/genetics
- Scavenger Receptors, Class B/genetics
- Scavenger Receptors, Class B/metabolism
- Ubiquitin-Protein Ligases/genetics
- Ubiquitin-Protein Ligases/metabolism
- Wound Healing/drug effects
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Affiliation(s)
- Joanne T M Tan
- The Heart Research Institute, Sydney, Australia Sydney Medical School, University of Sydney, Sydney, Australia
| | - Hamish C G Prosser
- The Heart Research Institute, Sydney, Australia Sydney Medical School, University of Sydney, Sydney, Australia
| | - Louise L Dunn
- The Heart Research Institute, Sydney, Australia Sydney Medical School, University of Sydney, Sydney, Australia
| | - Laura Z Vanags
- The Heart Research Institute, Sydney, Australia Sydney Medical School, University of Sydney, Sydney, Australia
| | - Anisyah Ridiandries
- The Heart Research Institute, Sydney, Australia Sydney Medical School, University of Sydney, Sydney, Australia
| | | | - Laura Lecce
- The Heart Research Institute, Sydney, Australia Sydney Medical School, University of Sydney, Sydney, Australia
| | - Zoë E Clayton
- The Heart Research Institute, Sydney, Australia Sydney Medical School, University of Sydney, Sydney, Australia
| | - Sui Ching G Yuen
- The Heart Research Institute, Sydney, Australia Sydney Medical School, University of Sydney, Sydney, Australia
| | - Stacy Robertson
- The Heart Research Institute, Sydney, Australia Sydney Medical School, University of Sydney, Sydney, Australia
| | - Yuen Ting Lam
- The Heart Research Institute, Sydney, Australia Sydney Medical School, University of Sydney, Sydney, Australia
| | - David S Celermajer
- The Heart Research Institute, Sydney, Australia Sydney Medical School, University of Sydney, Sydney, Australia Department of Cardiology, Royal Prince Alfred Hospital, Sydney, Australia
| | - Martin K C Ng
- The Heart Research Institute, Sydney, Australia Sydney Medical School, University of Sydney, Sydney, Australia Department of Cardiology, Royal Prince Alfred Hospital, Sydney, Australia
| | - Christina A Bursill
- The Heart Research Institute, Sydney, Australia Sydney Medical School, University of Sydney, Sydney, Australia
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Katare R, Rawal S, Munasinghe PE, Tsuchimochi H, Inagaki T, Fujii Y, Dixit P, Umetani K, Kangawa K, Shirai M, Schwenke DO. Ghrelin Promotes Functional Angiogenesis in a Mouse Model of Critical Limb Ischemia Through Activation of Proangiogenic MicroRNAs. Endocrinology 2016; 157:432-45. [PMID: 26672806 DOI: 10.1210/en.2015-1799] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Current therapeutic strategies for the treatment of critical limb ischemia (CLI) have only limited success. Recent in vitro evidence in the literature, using cell lines, proposes that the peptide hormone ghrelin may have angiogenic properties. In this study, we aim to investigate if ghrelin could promote postischemic angiogenesis in a mouse model of CLI and, further, identify the mechanistic pathway(s) that underpin ghrelin's proangiogenic properties. CLI was induced in male CD1 mice by femoral artery ligation. Animals were then randomized to receive either vehicle or acylated ghrelin (150 μg/kg sc) for 14 consecutive days. Subsequently, synchrotron radiation microangiography was used to assess hindlimb perfusion. Subsequent tissue samples were collected for molecular and histological analysis. Ghrelin treatment markedly improved limb perfusion by promoting the generation of new capillaries and arterioles (internal diameter less than 50 μm) within the ischemic hindlimb that were both structurally and functionally normal; evident by robust endothelium-dependent vasodilatory responses to acetylcholine. Molecular analysis revealed that ghrelin's angiogenic properties were linked to activation of prosurvival Akt/vascular endothelial growth factor/Bcl-2 signaling cascade, thus reducing the apoptotic cell death and subsequent fibrosis. Further, ghrelin treatment activated proangiogenic (miR-126 and miR-132) and antifibrotic (miR-30a) microRNAs (miRs) while inhibiting antiangiogenic (miR-92a and miR-206) miRs. Importantly, in vitro knockdown of key proangiogenic miRs (miR-126 and miR-132) inhibited the angiogenic potential of ghrelin. These results therefore suggest that clinical use of ghrelin for the early treatment of CLI may be a promising and potent inducer of reparative vascularization through modulation of key molecular factors.
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Affiliation(s)
- Rajesh Katare
- Department of Physiology, HeartOtago (R.K., S.R., P.E.M., P.D., D.O.S.), University of Otago, Dunedin, 9010 New Zealand; Department of Cardiac Physiology (H.T., T.I., Y.F., M.S.), National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, 565-8565 Japan; Japan Synchrotron Radiation Research Institute (K.U.), Hyogo, 679-5198 Japan; and Director (K.K.), National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, 565-8565 Japan
| | - Shruti Rawal
- Department of Physiology, HeartOtago (R.K., S.R., P.E.M., P.D., D.O.S.), University of Otago, Dunedin, 9010 New Zealand; Department of Cardiac Physiology (H.T., T.I., Y.F., M.S.), National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, 565-8565 Japan; Japan Synchrotron Radiation Research Institute (K.U.), Hyogo, 679-5198 Japan; and Director (K.K.), National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, 565-8565 Japan
| | - Pujika Emani Munasinghe
- Department of Physiology, HeartOtago (R.K., S.R., P.E.M., P.D., D.O.S.), University of Otago, Dunedin, 9010 New Zealand; Department of Cardiac Physiology (H.T., T.I., Y.F., M.S.), National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, 565-8565 Japan; Japan Synchrotron Radiation Research Institute (K.U.), Hyogo, 679-5198 Japan; and Director (K.K.), National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, 565-8565 Japan
| | - Hirotsugu Tsuchimochi
- Department of Physiology, HeartOtago (R.K., S.R., P.E.M., P.D., D.O.S.), University of Otago, Dunedin, 9010 New Zealand; Department of Cardiac Physiology (H.T., T.I., Y.F., M.S.), National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, 565-8565 Japan; Japan Synchrotron Radiation Research Institute (K.U.), Hyogo, 679-5198 Japan; and Director (K.K.), National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, 565-8565 Japan
| | - Tadakatsu Inagaki
- Department of Physiology, HeartOtago (R.K., S.R., P.E.M., P.D., D.O.S.), University of Otago, Dunedin, 9010 New Zealand; Department of Cardiac Physiology (H.T., T.I., Y.F., M.S.), National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, 565-8565 Japan; Japan Synchrotron Radiation Research Institute (K.U.), Hyogo, 679-5198 Japan; and Director (K.K.), National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, 565-8565 Japan
| | - Yutaka Fujii
- Department of Physiology, HeartOtago (R.K., S.R., P.E.M., P.D., D.O.S.), University of Otago, Dunedin, 9010 New Zealand; Department of Cardiac Physiology (H.T., T.I., Y.F., M.S.), National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, 565-8565 Japan; Japan Synchrotron Radiation Research Institute (K.U.), Hyogo, 679-5198 Japan; and Director (K.K.), National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, 565-8565 Japan
| | - Parul Dixit
- Department of Physiology, HeartOtago (R.K., S.R., P.E.M., P.D., D.O.S.), University of Otago, Dunedin, 9010 New Zealand; Department of Cardiac Physiology (H.T., T.I., Y.F., M.S.), National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, 565-8565 Japan; Japan Synchrotron Radiation Research Institute (K.U.), Hyogo, 679-5198 Japan; and Director (K.K.), National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, 565-8565 Japan
| | - Keiji Umetani
- Department of Physiology, HeartOtago (R.K., S.R., P.E.M., P.D., D.O.S.), University of Otago, Dunedin, 9010 New Zealand; Department of Cardiac Physiology (H.T., T.I., Y.F., M.S.), National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, 565-8565 Japan; Japan Synchrotron Radiation Research Institute (K.U.), Hyogo, 679-5198 Japan; and Director (K.K.), National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, 565-8565 Japan
| | - Kenji Kangawa
- Department of Physiology, HeartOtago (R.K., S.R., P.E.M., P.D., D.O.S.), University of Otago, Dunedin, 9010 New Zealand; Department of Cardiac Physiology (H.T., T.I., Y.F., M.S.), National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, 565-8565 Japan; Japan Synchrotron Radiation Research Institute (K.U.), Hyogo, 679-5198 Japan; and Director (K.K.), National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, 565-8565 Japan
| | - Mikiyasu Shirai
- Department of Physiology, HeartOtago (R.K., S.R., P.E.M., P.D., D.O.S.), University of Otago, Dunedin, 9010 New Zealand; Department of Cardiac Physiology (H.T., T.I., Y.F., M.S.), National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, 565-8565 Japan; Japan Synchrotron Radiation Research Institute (K.U.), Hyogo, 679-5198 Japan; and Director (K.K.), National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, 565-8565 Japan
| | - Daryl O Schwenke
- Department of Physiology, HeartOtago (R.K., S.R., P.E.M., P.D., D.O.S.), University of Otago, Dunedin, 9010 New Zealand; Department of Cardiac Physiology (H.T., T.I., Y.F., M.S.), National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, 565-8565 Japan; Japan Synchrotron Radiation Research Institute (K.U.), Hyogo, 679-5198 Japan; and Director (K.K.), National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, 565-8565 Japan
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Abstract
The insulin-secreting β-cells are contained within islets of Langerhans, which are highly vascularized. Blood cell flow rates through islets are glucose-dependent, even though there are no changes in blood cell flow within in the surrounding exocrine pancreas. This suggests a specific mechanism of glucose-regulated blood flow in the islet. Pancreatic islets respond to elevated glucose with synchronous pulses of electrical activity and insulin secretion across all β-cells in the islet. Connexin 36 (Cx36) gap junctions between islet β-cells mediate this synchronization, which is lost in Cx36 knockout mice (Cx36(-/-)). This leads to glucose intolerance in these mice, despite normal plasma insulin levels and insulin sensitivity. Thus, we sought to investigate whether the glucose-dependent changes in intraislet blood cell flow are also dependent on coordinated pulsatile electrical activity. We visualized and quantified blood cell flow using high-speed in vivo fluorescence imaging of labeled red blood cells and plasma. With the use of a live animal glucose clamp, blood cell flow was measured during either hypoglycemia (∼50 mg/dl) or hyperglycemia (∼300 mg/dl). In contrast to the large glucose-dependent islet blood velocity changes observed in wild-type mice, only minimal differences are observed in both Cx36(+/-) and Cx36(-/-) mice. This observation supports a novel model where intraislet blood cell flow is regulated by the coordinated electrical activity in the islet β-cells. Because Cx36 expression and function is reduced in type 2 diabetes, the resulting defect in intraislet blood cell flow regulation may also play a significant role in diabetic pathology.
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Affiliation(s)
- Kurt W Short
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, Tennessee
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Devanathan S, Nemanich ST, Kovacs A, Fettig N, Gropler RJ, Shoghi KI. Genomic and metabolic disposition of non-obese type 2 diabetic rats to increased myocardial fatty acid metabolism. PLoS One 2013; 8:e78477. [PMID: 24205240 PMCID: PMC3804536 DOI: 10.1371/journal.pone.0078477] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2013] [Accepted: 09/12/2013] [Indexed: 02/04/2023] Open
Abstract
Lipotoxicity of the heart has been implicated as a leading cause of morbidity in Type 2 Diabetes Mellitus (T2DM). While numerous reports have demonstrated increased myocardial fatty acid (FA) utilization in obese T2DM animal models, this diabetic phenotype has yet to be demonstrated in non-obese animal models of T2DM. Therefore, the present study investigates functional, metabolic, and genomic differences in myocardial FA metabolism in non-obese type 2 diabetic rats. The study utilized Goto-Kakizaki (GK) rats at the age of 24 weeks. Each rat was imaged with small animal positron emission tomography (PET) to estimate myocardial blood flow (MBF) and myocardial FA metabolism. Echocardiograms (ECHOs) were performed to assess cardiac function. Levels of triglycerides (TG) and non-esterified fatty acids (NEFA) were measured in both plasma and cardiac tissues. Finally, expression profiles for 168 genes that have been implicated in diabetes and FA metabolism were measured using quantitative PCR (qPCR) arrays. GK rats exhibited increased NEFA and TG in both plasma and cardiac tissue. Quantitative PET imaging suggests that GK rats have increased FA metabolism. ECHO data indicates that GK rats have a significant increase in left ventricle mass index (LVMI) and decrease in peak early diastolic mitral annular velocity (E’) compared to Wistar rats, suggesting structural remodeling and impaired diastolic function. Of the 84 genes in each the diabetes and FA metabolism arrays, 17 genes in the diabetes array and 41 genes in the FA metabolism array were significantly up-regulated in GK rats. Our data suggest that GK rats’ exhibit increased genomic disposition to FA and TG metabolism independent of obesity.
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Affiliation(s)
- Sriram Devanathan
- Department of Radiology, Washington University School of Medicine, St. Louis, Missouri, United States of America
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Bir SC, Shen X, Kavanagh TJ, Kevil CG, Pattillo CB. Control of angiogenesis dictated by picomolar superoxide levels. Free Radic Biol Med 2013; 63:135-42. [PMID: 23685287 PMCID: PMC3732119 DOI: 10.1016/j.freeradbiomed.2013.05.015] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/04/2013] [Revised: 05/08/2013] [Accepted: 05/09/2013] [Indexed: 12/12/2022]
Abstract
Control of vascular insufficiencies due to various cardiovascular pathologies is important for developing specific and effective treatments. Fluctuations in oxidative stress significantly alter the progression of angiogenesis under physiological and pathological conditions. However, the precise amount of reactive oxygen species (ROS) required to influence subsequent signaling pathways for ischemic angiogenesis remains undefined. Here, we have determined the effect of ROS-mediated molecular mechanisms on angiogenesis in a murine model of peripheral artery disease using Gclm mutant mice (a model of compromised glutathione synthesis and therefore reduced antioxidant capacity). Left femoral artery ligation and excision were performed in Gclm WT (+/+), heterozygous (+/-), and null (-/-) mice. Blood flow (laser Doppler), angiogenic index (CD31/DAPI), and proliferation index (Ki67/DAPI) were significantly increased in Gclm(+/-) mice but not in Gclm(+/+) or Gclm(-/-) mice. Measurements of reactive oxygen species suggest that the amount of superoxide required to stimulate angiogenesis after the induction of ischemia is 9.82 pmol/mg of tissue. Protein carbonyl levels increased in a manner consistent with increasing oxidative stress. Superoxide and protein carbonyl levels were reduced by the addition of the nitroxide tempol, a known superoxide dismutase mimetic. Finally, restoration of blood flow in Gclm(+/-) mice was attenuated by a VEGF164 aptamer, verifying that slightly elevated levels of ROS restore blood flow by stimulating endothelial cell proliferation through a VEGF-dependent pathway. The results of this study reveal new information on the amount of ROS necessary for angiogenic activity and provide the foundation of critical redox parameters for vascular remodeling responses. The information obtained from this study on vascular ischemia, using a model of decreased antioxidant capacity, has provided insight into the control of revascularization and is a step forward in our ability to regulate angiogenic therapies.
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Affiliation(s)
- Shyamal C Bir
- Department of Pathology, LSU Health Sciences Center-Shreveport, Shreveport, LA 71104
| | - Xinggui Shen
- Department of Pathology, LSU Health Sciences Center-Shreveport, Shreveport, LA 71104
| | - Terrance J Kavanagh
- Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA 98195
| | - Christopher G Kevil
- Department of Pathology, LSU Health Sciences Center-Shreveport, Shreveport, LA 71104
- Department of Molecular and Cellular Physiology, LSU Health Sciences Center-Shreveport, Shreveport, LA 71104
| | - Christopher B Pattillo
- Department of Molecular and Cellular Physiology, LSU Health Sciences Center-Shreveport, Shreveport, LA 71104
- Correspondence to: Christopher B. Pattillo, Ph.D., Department of Molecular and Cellular Physiology, LSU Health Sciences Center-Shreveport, 1501 Kings Hwy, Shreveport, LA 71130, , Phone: (318) 675-6974, Fax: (318) 675-6005
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Marshall KD, Muller BN, Krenz M, Hanft LM, McDonald KS, Dellsperger KC, Emter CA. Heart failure with preserved ejection fraction: chronic low-intensity interval exercise training preserves myocardial O2 balance and diastolic function. J Appl Physiol (1985) 2013; 114:131-47. [PMID: 23104696 PMCID: PMC3544520 DOI: 10.1152/japplphysiol.01059.2012] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2012] [Accepted: 10/23/2012] [Indexed: 12/17/2022] Open
Abstract
We have previously reported chronic low-intensity interval exercise training attenuates fibrosis, impaired cardiac mitochondrial function, and coronary vascular dysfunction in miniature swine with left ventricular (LV) hypertrophy (Emter CA, Baines CP. Am J Physiol Heart Circ Physiol 299: H1348-H1356, 2010; Emter CA, et al. Am J Physiol Heart Circ Physiol 301: H1687-H1694, 2011). The purpose of this study was to test two hypotheses: 1) chronic low-intensity interval training preserves normal myocardial oxygen supply/demand balance; and 2) training-dependent attenuation of LV fibrotic remodeling improves diastolic function in aortic-banded sedentary, exercise-trained (HF-TR), and control sedentary male Yucatan miniature swine displaying symptoms of heart failure with preserved ejection fraction. Pressure-volume loops, coronary blood flow, and two-dimensional speckle tracking ultrasound were utilized in vivo under conditions of increasing peripheral mean arterial pressure and β-adrenergic stimulation 6 mo postsurgery to evaluate cardiac function. Normal diastolic function in HF-TR animals was characterized by prevention of increased time constant of isovolumic relaxation, normal LV untwisting rate, and enhanced apical circumferential and radial strain rate. Reduced fibrosis, normal matrix metalloproteinase-2 and tissue inhibitors of metalloproteinase-4 mRNA expression, and increased collagen III isoform mRNA levels (P < 0.05) accompanied improved diastolic function following chronic training. Exercise-dependent improvements in coronary blood flow for a given myocardial oxygen consumption (P < 0.05) and cardiac efficiency (stroke work to myocardial oxygen consumption, P < 0.05) were associated with preserved contractile reserve. LV hypertrophy in HF-TR animals was associated with increased activation of Akt and preservation of activated JNK/SAPK. In conclusion, chronic low-intensity interval exercise training attenuates diastolic impairment by promoting compliant extracellular matrix fibrotic components and preserving extracellular matrix regulatory mechanisms, preserves myocardial oxygen balance, and promotes a physiological molecular hypertrophic signaling phenotype in a large animal model resembling heart failure with preserved ejection fraction.
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Affiliation(s)
- Kurt D Marshall
- Department of Biomedical Science, University of Missouri-Columbia, Columbia, Missouri 65211, USA
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8
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Rolny C, Mazzone M, Tugues S, Laoui D, Johansson I, Coulon C, Squadrito ML, Segura I, Li X, Knevels E, Costa S, Vinckier S, Dresselaer T, Åkerud P, De Mol M, Salomäki H, Phillipson M, Wyns S, Larsson E, Buysschaert I, Botling J, Himmelreich U, Van Ginderachter JA, De Palma M, Dewerchin M, Claesson-Welsh L, Carmeliet P. HRG inhibits tumor growth and metastasis by inducing macrophage polarization and vessel normalization through downregulation of PlGF. Cancer Cell 2011; 19:31-44. [PMID: 21215706 DOI: 10.1016/j.ccr.2010.11.009] [Citation(s) in RCA: 529] [Impact Index Per Article: 40.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/13/2010] [Revised: 08/12/2010] [Accepted: 10/25/2010] [Indexed: 11/15/2022]
Abstract
Polarization of tumor-associated macrophages (TAMs) to a proangiogenic/immune-suppressive (M2-like) phenotype and abnormal, hypoperfused vessels are hallmarks of malignancy, but their molecular basis and interrelationship remains enigmatic. We report that the host-produced histidine-rich glycoprotein (HRG) inhibits tumor growth and metastasis, while improving chemotherapy. By skewing TAM polarization away from the M2- to a tumor-inhibiting M1-like phenotype, HRG promotes antitumor immune responses and vessel normalization, effects known to decrease tumor growth and metastasis and to enhance chemotherapy. Skewing of TAM polarization by HRG relies substantially on downregulation of placental growth factor (PlGF). Besides unveiling an important role for TAM polarization in tumor vessel abnormalization, and its regulation by HRG/PlGF, these findings offer therapeutic opportunities for anticancer and antiangiogenic treatment.
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MESH Headings
- Animals
- Antibodies/immunology
- Antibodies/pharmacology
- CD8-Positive T-Lymphocytes/immunology
- CD8-Positive T-Lymphocytes/pathology
- Cell Line, Tumor
- Cell Proliferation/drug effects
- Chemotactic Factors/metabolism
- Clodronic Acid/pharmacology
- Culture Media, Conditioned/pharmacology
- Cytokines/metabolism
- Dendritic Cells/immunology
- Dendritic Cells/metabolism
- Dendritic Cells/pathology
- Down-Regulation/genetics
- Endothelial Cells/cytology
- Endothelial Cells/drug effects
- Gene Expression/drug effects
- Gene Expression/genetics
- Humans
- Hypoxia/genetics
- Hypoxia/metabolism
- Lung Neoplasms/genetics
- Lung Neoplasms/immunology
- Lung Neoplasms/pathology
- Lung Neoplasms/secondary
- Macrophages/drug effects
- Macrophages/immunology
- Macrophages/metabolism
- Macrophages/pathology
- Macrophages, Peritoneal/drug effects
- Macrophages, Peritoneal/metabolism
- Mice
- Mice, Inbred BALB C
- Mice, Inbred C57BL
- Mice, Knockout
- Microvessels/drug effects
- Microvessels/pathology
- Microvessels/ultrastructure
- Neoplasm Metastasis/genetics
- Neoplasm Metastasis/immunology
- Neoplasm Metastasis/pathology
- Neoplasms/blood supply
- Neoplasms/genetics
- Neoplasms/immunology
- Neoplasms/metabolism
- Neoplasms/pathology
- Neovascularization, Pathologic/genetics
- Neovascularization, Pathologic/immunology
- Neovascularization, Pathologic/pathology
- Placenta Growth Factor
- Pregnancy Proteins/genetics
- Pregnancy Proteins/immunology
- Pregnancy Proteins/metabolism
- Proteins/genetics
- Proteins/metabolism
- Proteins/pharmacology
- Regional Blood Flow/drug effects
- Regional Blood Flow/genetics
- Transfection
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Affiliation(s)
- Charlotte Rolny
- Uppsala University, Department of Genetics and Pathology, Rudbeck Laboratory, 75185 Uppsala, Sweden
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9
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Deev RV, Grigorian AS, Potapov IV, Kiselev SL, Isaev AA. [Worldwide experience and recent trends in gene therapy of ischaemic diseases]. Angiol Sosud Khir 2011; 17:145-54. [PMID: 21998874 DOI: pmid/21998874] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Fifteen odd years have passed since the first application of a gene-therapeutic modality in clinical practice for treatment of lower-limb chronic ischaemia. Over this time, vast experience has been gained worldwide, with not less than one thousand patients treated by gene-based therapies, thus making it possible to generalise the published findings of these clinical trials. Resulting from such an analysis, it should be recognized that the least dangerous gene therapeutic modalities available so far are plasmid ones, with the most efficient being those containing the gene of vascular endothelial growth factor VEGF(165). The most convincing results were obtained while treating chronic ischemia of the lower extremities, whereas gene-based therapy used for treatment of coronary artery disease failed to have yielded, as of yet, clear cut positive results.
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10
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Pettigrew LC, Kindy MS, Scheff S, Springer JE, Kryscio RJ, Li Y, Grass DS. Focal cerebral ischemia in the TNFalpha-transgenic rat. J Neuroinflammation 2008; 5:47. [PMID: 18947406 PMCID: PMC2583993 DOI: 10.1186/1742-2094-5-47] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2008] [Accepted: 10/23/2008] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND To determine if chronic elevation of the inflammatory cytokine, tumor necrosis factor-alpha (TNFalpha), will affect infarct volume or cortical perfusion after focal cerebral ischemia. METHODS Transgenic (TNFalpha-Tg) rats overexpressing the murine TNFalpha gene in brain were prepared by injection of mouse DNA into rat oocytes. Brain levels of TNFalpha mRNA and protein were measured and compared between TNFalpha-Tg and non-transgenic (non-Tg) littermates. Mean infarct volume was calculated 24 hours or 7 days after one hour of reversible middle cerebral artery occlusion (MCAO). Cortical perfusion was monitored by laser-Doppler flowmetry (LDF) during MCAO. Cortical vascular density was quantified by stereology. Post-ischemic cell death was assessed by immunohistochemistry and regional measurement of caspase-3 activity or DNA fragmentation. Unpaired t tests or analysis of variance with post hoc tests were used for comparison of group means. RESULTS In TNFalpha-Tg rat brain, the aggregate mouse and rat TNFalpha mRNA level was fourfold higher than in non-Tg littermates and the corresponding TNFalpha protein level was increased fivefold (p CONCLUSION Chronic elevation of TNFalpha protein in brain increases susceptibility to ischemic injury but has no effect on vascular density. TNFalpha-Tg animals are more susceptible to apoptotic cell death after MCAO than are non-Tg animals. We conclude that the TNFalpha-Tg rat is a valuable new tool for the study of cytokine-mediated ischemic brain injury.
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Affiliation(s)
- L Creed Pettigrew
- Sanders-Brown Center on Aging, University of Kentucky, Lexington, Kentucky, USA
- Department of Neurology, University of Kentucky, Lexington, Kentucky, USA
- Veterans Administration (VA) Medical Center, Lexington, Kentucky, USA
| | - Mark S Kindy
- Department of Neuroscience, Medical University of South Carolina, Charleston, South Carolina, USA
- Ralph H. Johnson VA Medical Center, Charleston, South Carolina, USA
| | - Stephen Scheff
- Sanders-Brown Center on Aging, University of Kentucky, Lexington, Kentucky, USA
| | - Joe E Springer
- Department of Physical Medicine & Rehabilitation, University of Kentucky, Lexington, Kentucky, USA
| | - Richard J Kryscio
- Department of Statistics and School of Public Health, University of Kentucky, Lexington, Kentucky, USA
| | - Yizhao Li
- Jinan Great Wall Hospital, Jinan, Shandong, PR China
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11
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Abstract
Targeted inactivation of genes involved in murine cardiovascular development frequently leads to abnormalities in blood flow. As blood fluid dynamics play a crucial role in shaping vessel morphology, the presence of flow defects generally prohibits the precise assignment of the role of the mutated gene product in the vasculature. In this study, we show how to distinguish between genetic defects caused by targeted inactivation of the neuropilin 1 (Nrp1) receptor and hemodynamic defects occurring in homozygous knockout embryos. Our analysis of a Nrp1 null allele bred onto a C57BL/6 background shows that vessel remodeling defects occur concomitantly with the onset of blood flow and cause death of homozygous mutants at E10.5. Using mouse embryo culture, we establish that hemodynamic defects are already present at E8.5 and continuous circulation is never established in homozygous mutants. The geometry of yolk sac blood vessels is altered and remodeling into yolk sac arteries and veins does not occur. To separate flow-induced deficiencies from those caused by the Nrp1 mutation, we arrested blood flow in cultured wild-type and mutant embryos and followed their vascular development. We find that loss of Nrp1 function rather than flow induces the altered geometry of the capillary plexus. Endothelial cell migration, but not replication, is altered in Nrp1 mutants. Gene expression analysis of endothelial cells isolated from freshly dissected wild-type and mutants and after culture in no-flow conditions showed down-regulation of the arterial marker genes connexin 40 and ephrin B2 related to the loss of Nrp1 function. This method allows genetic defects caused by loss-of-function of a gene important for cardiovascular development to be isolated even in the presence of hemodynamic defects.
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12
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Abstract
BACKGROUND Endothelial dysfunction assessed by brachial artery flow-mediated dilation (FMD) is a marker for early atherosclerotic vascular disease and future cardiovascular events. OBJECTIVE To estimate the heritability of brachial artery FMD using a twin design. METHODS We estimated the heritability of FMD using 94 middle-aged male twin pairs. FMD was measured by ultrasound, and traditional coronary heart disease risk factors were measured. Genetic modeling techniques were used to determine the relative contributions of genes and environment to the variation in FMD. RESULTS The mean age of the twin participants was 54.9 +/- 2.8 years. The mean FMD was 0.047 +/- 0.030. The intraclass correlation coefficient was higher in MZ twins [0.38, 95% confidence interval (CI) 0.32-0.43] than in DZ twins (0.19, 95% CI 0.11-0.26), suggesting a role of genetic influence in FMD variation. Structural equation modeling showed that both genetic and unique environmental factors contributed significantly to the variation in FMD. The crude FMD heritability was 0.37 (95% CI 0.15-0.54). After adjustment for traditional cardiovascular risk factors, including age, total cholesterol, blood pressure, and body mass index, the heritability of FMD was 39% (95% CI 0.18-0.56). The remaining variation in FMD could be explained by individual-specific environment. CONCLUSION This is the first study using twins to estimate the relative contributions of genetics and environment to the variation in FMD in a US population. Our results demonstrate a moderate genetic effect on brachial artery FMD, independent of traditional coronary risk factors. Our data also highlight the importance of unique environment on the variability in FMD.
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Affiliation(s)
- J Zhao
- Department of Medicine, Division of Cardiology, Emory University School of Medicine, 1256 Briarcliff Road NE, Atlanta, GA 30306, USA
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13
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Ge D, Young TW, Wang X, Kapuku GK, Treiber FA, Snieder H. Heritability of arterial stiffness in black and white American youth and young adults. Am J Hypertens 2007; 20:1065-72. [PMID: 17903689 PMCID: PMC3672691 DOI: 10.1016/j.amjhyper.2007.05.013] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2007] [Revised: 02/26/2007] [Accepted: 05/24/2007] [Indexed: 01/25/2023] Open
Abstract
BACKGROUND Our objectives were to examine the heritability of arterial stiffness measured as pulse-wave velocity (PWV), and its dependence on ethnicity, gender, and blood pressure (BP). METHODS As part of the Georgia Cardiovascular Twin Study, we measured aorto-radial (radial) and aorto-dorsalis-pedis (foot) PWV in 702 twins (41% black; 49% male) aged 12 to 30 years (mean age, 17.7 +/- 3.3 years), including monozygotic and dizygotic pairs of the same as well as opposite gender. Ethnicity and gender effects on genetic and environmental contributions to PWV were estimated by genetic model fitting. RESULTS Diastolic BP was the most important hemodynamic predictor. The best-fitting models showed no ethnicity or gender differences in estimates of genetic and environmental influence, and indicated substantial heritabilities of 0.43 (95% confidence interval, 0.30 to 0.54) and 0.53 (95% confidence interval, 0.42 to 0.62) for radial and foot PWV, respectively. Over a quarter of these heritabilities (0.19 for radial PWV; 0.14 for foot PWV) could be attributed to genes that also influenced diastolic BP, as based on multivariate models. CONCLUSIONS Individual differences in the arterial stiffness of youth and young adults are substantially heritable, and >25% of this heritability is explained by genes that also influence diastolic BP. Heritability estimates do not show any differences between blacks and whites or males and females.
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Affiliation(s)
- Dongliang Ge
- Georgia Prevention Institute, Department of Pediatrics, Medical College of Georgia, Augusta, GA, USA
| | - Thomas W. Young
- Dept. of Pediatrics, Sections of Pediatric Cardiology and Pediatric Pulmonology; Medical College of Georgia; Augusta, GA, USA
| | - Xiaoling Wang
- Georgia Prevention Institute, Department of Pediatrics, Medical College of Georgia, Augusta, GA, USA
| | - Gaston K. Kapuku
- Georgia Prevention Institute, Department of Pediatrics, Medical College of Georgia, Augusta, GA, USA
| | - Frank A. Treiber
- Georgia Prevention Institute, Department of Pediatrics, Medical College of Georgia, Augusta, GA, USA
| | - Harold Snieder
- Georgia Prevention Institute, Department of Pediatrics, Medical College of Georgia, Augusta, GA, USA
- Twin Research & Genetic Epidemiology Unit, St Thomas’ Campus, King’s College, London, UK
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14
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Rao H, Gillihan SJ, Wang J, Korczykowski M, Sankoorikal GMV, Kaercher KA, Brodkin ES, Detre JA, Farah MJ. Genetic variation in serotonin transporter alters resting brain function in healthy individuals. Biol Psychiatry 2007; 62:600-6. [PMID: 17481593 DOI: 10.1016/j.biopsych.2006.11.028] [Citation(s) in RCA: 115] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/20/2006] [Revised: 11/21/2006] [Accepted: 11/22/2006] [Indexed: 12/16/2022]
Abstract
BACKGROUND Perfusion functional magnetic resonance imaging (fMRI) was used to investigate the effect of genetic variation of the human serotonin transporter (5-HTT) gene (5-HTTLPR, SLC6A4) on resting brain function of healthy individuals. METHODS Twenty-six healthy subjects, half homozygous for the 5-HTTLPR short allele (s/s group) and half homozygous for the long allele (l/l group), underwent perfusion functional and structural magnetic resonance imaging during a resting state. The two genotype groups had no psychiatric illness and were similar in age, gender, and personality scores. RESULTS Compared with the l/l group, the s/s group showed significantly increased resting cerebral blood flow (CBF) in the amygdala and decreased CBF in the ventromedial prefrontal cortex. The effect of functional modulation in these regions by 5-HTTLPR genotype cannot be accounted for by variations in brain anatomy, personality, or self-reported mood. CONCLUSIONS The 5-HTTLPR genotype alters resting brain function in emotion-related regions in healthy individuals, including the amygdala and ventromedial prefrontal cortex. Such alterations suggest a broad role of the 5-HTT gene in brain function that may be associated with the genetic susceptibility for mood disorders such as depression.
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Affiliation(s)
- Hengyi Rao
- Center for Functional Neuroimaging, Department of Neurology and Radiology, University of Pennsylvania, 3400 Spruce Street, Philadelphia, PA 19104, USA.
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15
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Abstract
BACKGROUND Opioids have been linked to limbic system activation and, in animals, to neurotoxicity. Limbic system nonpharmacologic activation patterns have been linked to the Apolipoprotein E (ApoE) allelic distribution. We tested the hypothesis that, in the absence of surgery, small doses of remifentanil produce limbic system activation in humans which varies with dose and ApoE genotype. METHODS Twenty-seven ASA I-II volunteers received a remifentanil (Ultiva) infusion at four sequentially increasing doses: 0, 0.05, 0.1, and 0.2 microg x kg(-1) x min(-1) while receiving 100% oxygen. Cerebral blood flow (CBF) was measured at each dose globally and in the amygdala, cingulate, hippocampus, insula, and thalamus regions by pulsed arterial spin labeling magnetic resonance imaging. ApoE single nucleotide polymorphisms were determined in each subject. RESULTS Significant dose-related CBF increases, without correction for Paco(2), were detected in all areas. After normalizing for global CBF to correct for Paco(2) effects, the remifentanil-mediated increased CBF in the cingulate persisted, with decreased flow occurring in the hippocampus and amygdala. All these Paco(2)-corrected effects were reversed in the presence of the ApoE4 polymorphism. CONCLUSION Remifentanil at sedative doses produces both activating and depressing effects in various limbic system structures. The cingulate cortex seems to have the most susceptibility to remifentanil activation, and ApoE4 seems to produce relative activation of the hippocampus and amygdala.
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Affiliation(s)
- W Andrew Kofke
- Department of Anesthesiology and Critical Care, Hospital of the University of Pennsylvania, Philadelphia, PA 19104-4283, USA.
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16
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Wilson MJ, Lopez M, Vargas M, Julian C, Tellez W, Rodriguez A, Bigham A, Armaza JF, Niermeyer S, Shriver M, Vargas E, Moore LG. Greater uterine artery blood flow during pregnancy in multigenerational (Andean) than shorter-term (European) high-altitude residents. Am J Physiol Regul Integr Comp Physiol 2007; 293:R1313-24. [PMID: 17581833 DOI: 10.1152/ajpregu.00806.2006] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Multigenerational (Andean) compared with shorter-term (European) high-altitude residents exhibit less hypoxia-associated reductions in birth weight. Because differences in arterial O(2) content are not responsible, we asked whether greater pregnancy-associated increases in uterine artery (UA) blood flow and O(2) delivery were involved. Serial studies were conducted in 42 Andean and 26 European residents of La Paz, Bolivia (3600 m) at weeks 20, 30, 36 of pregnancy and 4 mo postpartum using Doppler ultrasound. There were no differences postpartum but Andean vs. European women had greater UA diameter (0.65 +/- 0.01 vs. 0.56 +/- 0.01 cm), cross-sectional area (33.1 +/- 0.97 vs. 24.7 +/- 1.18 mm(2)), and blood flow at week 36 (743 +/- 87 vs. 474 +/- 36 ml/min) (all P < 0.05) and thus 1.6-fold greater uteroplacental O(2) delivery near term (126.82 +/- 18.47 vs. 80.33 +/- 8.69 ml O(2).ml blood(-1).min(-1), P < 0.05). Andeans had greater common iliac (CI) flow and lower external iliac relative to CI flow (0.52 +/- 0.11 vs. 0.95 +/- 0.14, P < 0.05) than Europeans at week 36. After adjusting for gestational age, maternal height, and parity, Andean babies weighed 209 g more than the Europeans. Greater UA cross-sectional area at week 30 related positively to birth weight in Andeans (r = +0.39) but negatively in Europeans (r = -0.37) (both P < 0.01). We concluded that a greater pregnancy-associated increase in UA diameter raised UA blood flow and uteroplacental O(2) delivery in the Andeans and contributed to their ability to maintain normal fetal growth under conditions of high-altitude hypoxia. These data implicate the involvement of genetic factors in protecting multigenerational populations from hypoxia-associated reductions in fetal growth, but future studies are required for confirmation and identification of the specific genes involved.
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Affiliation(s)
- Megan J Wilson
- Altitude Research Center, University of Colorado at Denver and Health Sciences Center, 4200 East Ninth Avenue, Denver, CO 80262, USA.
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17
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Mitchell GF, Guo CY, Kathiresan S, Vasan RS, Larson MG, Vita JA, Keyes MJ, Vyas M, Newton-Cheh C, Musone SL, Camargo AL, Drake JA, Levy D, O'Donnell CJ, Hirschhorn JN, Benjamin EJ. Vascular Stiffness and Genetic Variation at the Endothelial Nitric Oxide Synthase Locus. Hypertension 2007; 49:1285-90. [PMID: 17404185 DOI: 10.1161/hypertensionaha.106.085266] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Arterial stiffness is a moderately heritable trait that is affected by alterations in the bioavailability of NO. Previous studies have found associations between variants in the gene for endothelial NO synthase (
NOS3
) and arterial properties. We previously identified a linkage peak for forward pressure wave amplitude in the immediate vicinity of
NOS3
. Therefore, we evaluated relations between arterial stiffness measures and common genetic variants at this locus. Eighteen single nucleotide polymorphisms capturing ≈90% of underlying common variation in
NOS3
were genotyped in unrelated Framingham Heart Study participants (N=1157; 52.2% women; mean age: 62 years) with routinely ascertained tonometry data that provided 5 arterial phenotypes (forward and reflected pressure wave amplitude, central pulse pressure, carotid–femoral pulse wave velocity, and mean arterial pressure). In women but not men, the genotype for the common
NOS3
missense mutation (Glu298Asp, rs1799983) was related to central pulse pressure (women: GG=53±0.9, GT=54±0.9, and TT=47±2.0 mm Hg,
P
=0.0047; men: GG=50±1.0, GT=49±0.9, and TT=47±1.8 mm Hg,
P
=0.30) and forward wave amplitude (women: GG=41±0.7, GT=42±0.7, and TT=38±1.6 mm Hg,
P
=0.029; men: GG=42±0.9, GT=41±0.8, and TT=39±1.5 mm Hg,
P
=0.47). The only other nominally significant sex-specific association in men but not women was between an intronic polymorphism (rs1800781) and reflected wave amplitude (women: AA=10.4±0.4, AG=11.1±0.6, and GG=8.9±2.2 mm Hg,
P
=0.50; men: AA=6.1±0.3, AG=7.3±0.5, and GG=11.3±2.3 mm Hg,
P
=0.014). After adjusting for multiple testing (18 polymorphisms and 5 phenotypes), these nominal associations were no longer significant. The present study was suggestive of modest relations between common genetic variants at the
NOS3
locus and arterial stiffness.
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18
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Ferreira MAND, Barcelos LS, Teixeira MM, Bakhle YS, Andrade SP. Tumor growth, angiogenesis and inflammation in mice lacking receptors for platelet activating factor (PAF). Life Sci 2007; 81:210-7. [PMID: 17588613 DOI: 10.1016/j.lfs.2007.05.003] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2007] [Revised: 04/24/2007] [Accepted: 05/02/2007] [Indexed: 11/28/2022]
Abstract
Tumor growth is associated with angiogenesis and inflammation and the endogenous lipid, platelet activating factor (PAF), is a pro-inflammatory and pro-angiogenic mediator. We therefore measured tumor growth, angiogenesis and inflammation in normal (WT) mice and those lacking the receptor for PAF, through gene deletion (PAFR-KO). Growth of solid tumors derived from colon 26 cells was not altered but that from Ehrlich cells was markedly (5-fold) increased in the PAFR-KO mice, relative to the WT strain. Angiogenesis, as tumor content of VEGF or hemoglobin, was increased in both tumors from the mutant strain. Inflammation, as neutrophil and macrophage accumulation and chemokine (CXCL2 and CCL2) content of tumors, was decreased or unchanged in the tumors implying an overall decrease in the inflammatory response in the PAFR-KO strain. We also assessed growth of the Ehrlich tumor in its ascites form, after i.p. injection. Here growth (ascites volume) was inhibited by about 30%, but neutrophil and macrophage numbers were increased in the ascites fluid from the PAFR-KO mice. Angiogenesis in the peritoneal wall, which is not invaded by the tumor cells, was increased but leukocyte infiltration decreased in the mutant strain. Our results show, unexpectedly, that tumor-induced angiogenesis was increased in mice lacking response to PAF, from which we infer that in normal (WT) mice, PAF is anti-angiogenic. Further, although growth was still associated with angiogenesis in PAFR-KO mice, growth was not correlated with inflammation (leukocyte accumulation).
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Affiliation(s)
- M A N D Ferreira
- Department of Physiology , General Pathology, Institute of Biological Sciences, Federal University of Minas Gerais, Av. Antonio Carlos 6627, Cx Post 468, Campus Pampulha, CEP 31270-901, Belo Horizonte/MG, Brazil
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19
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Pretorius MM, Gainer JV, Van Guilder GP, Coelho EB, Luther JM, Fong P, Rosenbaum DD, Malave HA, Yu C, Ritchie MD, Vaughan DE, Brown NJ. The Bradykinin Type 2 Receptor BE1 Polymorphism and Ethnicity Influence Systolic Blood Pressure and Vascular Resistance. Clin Pharmacol Ther 2007; 83:122-9. [PMID: 17522594 DOI: 10.1038/sj.clpt.6100250] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
We examined the effect of -58 C/T and BE1 +9/-9 polymorphisms in the bradykinin B2 receptor gene on forearm vascular resistance (FVR) before and during intrabrachial artery infusion of the B2 receptor-, endothelium-dependent agonist bradykinin and the endothelium-independent agonist sodium nitroprusside in 228 normotensive subjects. In 166 white Americans, systolic blood pressure (SBP) and pulse pressure were highest in the BE1 +9/+9 group (118+/-2 and 51+/-2 mm Hg, respectively; P<0.05 versus -9/-9 for either), intermediate in the +9/-9 group (114+/-1 and 49+/-1 mm Hg, P<0.05 versus -9/-9 for pulse pressure), and lowest in the -9/-9 group (110+/-2 and 44+/-2 mm Hg). In 62 black Americans, FVR was 25% higher in the BE1 +9/+9 group compared with the BE1 +9/-9 and -9/-9 groups at baseline (P=0.038) or during bradykinin (P=0.03). Increased SBP or vascular resistance may contribute to increased left ventricular mass reported previously in individuals with the BE1+9/+9 genotype.
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Affiliation(s)
- M M Pretorius
- Department of Anesthesiology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
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20
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Suzuki K, Juo SHH, Rundek T, Boden-Albala B, Disla N, Liu R, Park N, Di Tullio MR, Sacco RL, Homma S. Genetic contribution to brachial artery flow-mediated dilation: the Northern Manhattan Family Study. Atherosclerosis 2007; 197:212-6. [PMID: 17462653 PMCID: PMC2268620 DOI: 10.1016/j.atherosclerosis.2007.03.023] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/06/2006] [Revised: 02/27/2007] [Accepted: 03/16/2007] [Indexed: 01/22/2023]
Abstract
BACKGROUND Brachial artery flow-mediated dilation (FMD) is a non-invasive measure of endothelial function. Endothelial dysfunction has been associated with traditional vascular risk factors and increased risk of cardiovascular disease. The importance of genetic contribution to FMD and baseline brachial artery diameter has not been shown in Hispanic populations. The purpose of this study was to estimate the heritability of FMD. METHODS Flow mediated dilation and brachial artery diameter were measured in a subset of Caribbean Hispanic families from the ongoing Northern Manhattan Family Study (NOMAFS), which studies the contribution of genetics to stroke and cardiovascular risk factors. The age- and sex-adjusted heritability of FMD was estimated using variance component methods. RESULTS The current data include 620 subjects (97 probands and 523 relatives) from 97 families. The age and sex-adjusted heritability of brachial artery diameter was 0.57 (p<0.01). The age- and sex-adjusted heritability of FMD was 0.20 (p=0.01). After additional adjustment for systolic and diastolic blood pressure, body mass index, smoking, lipid, diabetes mellitus, medication, and baseline brachial artery diameter, the heritability of FMD was 0.17 (p=0.01). CONCLUSIONS We found modest heritability of FMD. FMD might be a reasonable phenotype for further investigation of genetic contribution to atherosclerosis.
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Affiliation(s)
- Keiko Suzuki
- Division of Cardiology, Department of Medicine, Columbia University College of Physicians and Surgeons, 630 West 168th Street, New York, NY 10032, USA.
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21
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Wanner SP, Guimarães JB, Rodrigues LOC, Marubayashi U, Coimbra CC, Lima NRV. Muscarinic cholinoceptors in the ventromedial hypothalamic nucleus facilitate tail heat loss during physical exercise. Brain Res Bull 2007; 73:28-33. [PMID: 17499633 DOI: 10.1016/j.brainresbull.2007.03.004] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2006] [Revised: 03/09/2007] [Accepted: 03/09/2007] [Indexed: 11/17/2022]
Abstract
The aim of this study was to evaluate the participation of ventromedial hypothalamic nucleus (VMH) muscarinic cholinoceptors in heat balance and central fatigue during treadmill exercise (24 m min(-1), 5% inclination). The animals were anesthetized with pentobarbital sodium (50 mg/kg body weight i.p.) and fitted with bilateral cannulae into the VMH 1 week prior to the experiments. Tail skin (T(tail)) and core body temperatures (T(b)) were measured after the injection of 0.2 microL of 5 x 10(-9) mol methylatropine (Matr) or 0.15 M NaCl solution (Sal) into the hypothalamus. Methylatropine injection into the VMH greatly increased heat storage rate (HSR) measured until fatigue (19.7+/-4.6 cal min(-1) Matr versus 9.7+/-3.3 cal min(-1) Sal; P<0.05) and attenuated the exercise-induced tail vasodilation as seen by T(tail) (23.98+/-0.43 degrees C Matr versus 25.52+/-0.85 degrees C Sal; at 6.5 min; P<0.05), indicating inhibition of the heat loss process. The 2 min delay and the increased DeltaT(b), which triggered the heat loss mechanisms observed in Matr-treated rats, are associated with increased HSR and may be responsible for the decreased running performance of these animals (21.0+/-2.9 min Matr versus 33.5+/-3.4 min Sal; P<0.001). In fact, a close negative correlation was observed between HSR and time to fatigue (r=-0.61; P<0.01). In conclusion, VMH muscarinic cholinoceptors facilitate tail heat loss mechanisms, and a delay in this adjustment would lead to a decrease in physical exercise performance due to excess heat storage.
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Affiliation(s)
- Samuel P Wanner
- Exercise Physiology Laboratory, Department of Physical Education, School of Physical Education, Federal University of Minas Gerais, Av. Antônio Carlos, 6627, 31270-901 Belo Horizonte, Minas Gerais, Brazil
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22
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Chen F, Tan Z, Dong CY, Chen X, Guo SF. Adeno-associated virus vectors simultaneously encoding VEGF and angiopoietin-1 enhances neovascularization in ischemic rabbit hind-limbs. Acta Pharmacol Sin 2007; 28:493-502. [PMID: 17376288 DOI: 10.1111/j.1745-7254.2007.00527.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
AIM Angiopoietin-1 (Ang1) and vascular endothelial growth factor A (VEGF) play important roles in vascular formation and maturation, suggesting a combination of these 2 would be a promising therapy for ischemic diseases. So we constructed an adeno-associated virus (AAV) vector, simultaneously encoding human VEGF(165) and Ang1 (AAV-VEGF/Ang1), and investigated its therapeutic effect in a rabbit ischemic hind-limb model. METHODS Four experimental groups were used to prepare the rabbit ischemic hind-limb model following AAV vectors intramuscular administration as follows: PBS (phosphate buffered solution), AAV-VEGF, AAV-Ang1, AAV-VEGF/Ang1. RESULTS Eight weeks after administration, human VEGF(165) and Ang1 were detected by RT-PCR, Western blotting and histochemical staining methods in AAV-VEGF/Ang1 transduced muscles. Group AAV-VEGF/Ang1 showed a significantly increased blood-flow recovery in ischemic hind-limbs compared with the other groups. Histological staining for alkaline phosphatase showed that capillary density of group AAV-VEGF/Ang1 or AAV-VEGF was significantly higher than that of group PBS or AAV-Ang1. Histological immunostaining for smooth muscle alpha-actin (alpha-SMA) revealed that group AAV-VEGF/Ang1 had the highest density of alpha-SMA-positive vessels compared with the other groups. Vascular leakage, one of the major adverse effects induced by VEGF, was very severe in group AAV-VEGF, but the permeability was obviously reduced when VEGF was co-expressed with Ang1 in group AAV-VEGF/Ang1. CONCLUSION AAV vectors can simultaneously encode 2 proteins which can be efficiently and stably co-expressed in transduced tissues. AAV-mediated VEGF and Ang1 gene transfer enhances neovascularization, prevents capillary leakage, and improves blood flow in a rabbit hind-limb ischemic model. These findings suggest that intramuscular administration of AAV-VEGF/Ang1 may be useful in the treatment of ischemic diseases.
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Affiliation(s)
- Feng Chen
- Department of Vascular Surgery, Zhongnan Hospital, Wuhan University, Wuhan 430071, China
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23
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Abstract
P-selectin is a 140-kDa glycoprotein expressed on endothelial cells and platelets. P-selectin mediates the tethering and rolling of leukocytes along the endothelium, an early step of leukocyte extravasation. Although inflammation is a requisite process for ischemia-induced angiogenesis, little is known regarding the role of P-selectin in angiogenesis in the setting of tissue ischemia. We examined whether ischemia-induced angiogenesis is altered in P-selectin knockout (P-selectin(-/-)) mice. Angiogenesis was evaluated in a surgically induced hind-limb ischemia model using laser Doppler blood flowmetry (LDBF) and histological capillary density (CD). After left hind-limb ischemia, the ischemic/normal limb LDBF ratio was persistently lower in P-selectin(-/-) mice compared with wild-type (WT) mice. CD was also significantly lower in P-selectin(-/-) mice than in WT mice on Postoperative Day 14. Fewer numbers of total CD45+ inflammatory leukocytes infiltrated into the ischemic tissues in P-selectin(-/-) mice than in WT mice, and immunohistochemical analysis revealed the number of infiltrated leukocytes expressing vascular endothelial growth factor was also decreased in P-selectin(-/-) mice. P-selectin mRNA expression was augmented after hind-limb ischemia in WT mice. In conclusion, P-selectin may play an important role in ischemia-induced angiogenesis by promoting early inflammatory mononuclear cell infiltration. P-selectin would become one possible target molecule for modulating inflammatory angiogenesis.
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Affiliation(s)
- Kimiyasu Egami
- Department of Pediatrics, Kurume University School of Medicine, Japan
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24
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Mitchell A, Lückebergfeld B, Bührmann S, Rushentsova U, Nürnberger J, Siffert W, Schäfers RF, Philipp T, Wenzel RR. Effects of systemic endothelin A receptor antagonism in various vascular beds in men: In vivo interactions of the major blood pressure?regulating systems and associations with the C825T polymorphism. Clin Pharmacol Ther 2004; 76:396-408. [PMID: 15536455 DOI: 10.1016/j.clpt.2004.07.011] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE We used the orally available endothelin A (ETA) receptor antagonist darusentan to characterize interactions between the major blood pressure-regulating systems in healthy men. Mediators of the endothelin system, the sympathetic nervous system, and the renin-angiotensin system act via G protein-coupled receptors with a possible involvement of the G-protein beta3 subunit (GNB3) C825T polymorphism. We studied the influence of this polymorphism on the responses to ETA antagonism in the presence of endothelin 1 (ET-1), norepinephrine (NA), and angiotensin II (ANGII). METHODS Thirty-seven individuals were included in a randomized, double-blind, placebo-controlled, crossover trial with 100 mg darusentan. Systemic hemodynamics and plasma ET-1, NA, and ANGII concentrations were assessed. Local studies were performed in the dorsal hand veins (n=18) and skin microcirculation (n=12), respectively. RESULTS Darusentan lowered systolic and diastolic blood pressure ( P <.001 versus placebo) without any differences according to genotype (mean maximum Delta systolic blood pressure, -7 +/- 2 mmHg for CT/TT versus -5 +/- 3 mmHg for CC, P=.37; mean maximum Delta diastolic blood pressure, -3 +/- 2 mmHg for CT/TT versus -4 +/- 2 mmHg for CC, P=.96). Venoconstriction to ET-1 and NA was not affected by ET A blockade in either group; however, carriers of the 825T allele demonstrated a markedly enhanced venoconstriction to ET-1 and NA (median effective concentration [ED50] for ET-1 after darusentan [placebo]: 2.5 +/- 0.2 pmol/min for CT/TT [2.7 +/- 0.3 pmol/min], P=.42; 3.9 +/- 0.6 pmol/min for CC [4.6 +/- 0.3 pmol/min], P=.42; P=.046 [P=.0005] for CT/TT versus CC) (ED50 for NA after darusentan [placebo]: 5.2 +/- 1.2 ng/min for CT/TT [7.3 +/- 1.2 ng/min], P=.20; 32.9 +/- 7.1 ng/min for CC [19.7 +/- 5.5 ng/min], P=.75; P=.0008 [P=.026] for CT/TT versus CC). Darusentan dilated veins at baseline in CC homozygous subjects (+0.21 +/- 0.05 mm, P=.004 versus placebo). Systemic ET A antagonism inhibited constriction to ET-1 and also to NA and ANGII in the skin microcirculation without differences according to genotype (ET-1, P=.017 for all individuals versus placebo; NA, P=.0005; and ANGII, P=.002). CONCLUSION GNB3 C825T allele carrier status did not influence systemic hemodynamic or local vascular responses to ET A blockade with darusentan in young, healthy men. However, it determined venoconstriction to exogenous ET-1 and NA. Darusentan markedly inhibited not only ET-1-induced but also NA-induced and ANGII-induced vasoconstriction in the skin microcirculation. In contrast, it had no effects on either ET-1-mediated or NA-mediated venoconstriction, indicating that, in the presence of high local ET-1 concentrations, constrictive endothelin B receptors may be of greater importance in the venous vasculature than has been recognized so far.
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Affiliation(s)
- Anna Mitchell
- Department of Nephrology and Hypertension, Essen University Hospital, Germany
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25
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Namba T, Koike H, Murakami K, Aoki M, Makino H, Hashiya N, Ogihara T, Kaneda Y, Kohno M, Morishita R. Angiogenesis induced by endothelial nitric oxide synthase gene through vascular endothelial growth factor expression in a rat hindlimb ischemia model. Circulation 2003; 108:2250-7. [PMID: 14568906 DOI: 10.1161/01.cir.0000093190.53478.78] [Citation(s) in RCA: 125] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
BACKGROUND Because the mechanism of the angiogenic property of nitric oxide (NO) was not fully understood in vivo, we focused on the role of vascular endothelial growth factor (VEGF) in angiogenesis induced by endothelial NO synthase (eNOS) gene transfer. METHODS AND RESULTS After intramuscular injection of eNOS DNA into a rat ischemic hindlimb, transfection of eNOS vector resulted in a significant increase in eNOS protein 1 week after transfection. In addition, tissue concentrations of nitrite and nitrate were significantly increased in rats transfected with the eNOS gene up to 2 weeks after transfection. The increase in tissue nitrite and nitrate concentrations was completely inhibited by NG-nitro-L-arginine methyl ester (L-NAME). In contrast, serum concentrations of nitrite and nitrate and blood pressure were not changed by eNOS gene transfer. Importantly, overexpression of the eNOS gene resulted in a significant increase in peripheral blood flow, whereas L-NAME inhibited the increase in blood flow. Interestingly, basal blood flow was significantly lower in rats treated with L-NAME than in control rats. A significant increase in capillary number was consistently detected in rats transfected with the eNOS gene at 4 weeks after transfection, accompanied by a significant increase in VEGF. Moreover, administration of neutralizing anti-VEGF antibody abolished the increase in blood flow and capillary density induced by eNOS plasmid injection. CONCLUSIONS Overall, intramuscular injection of bovine eNOS plasmid induced therapeutic angiogenesis in a rat ischemic hindlimb model, a potential therapy for peripheral arterial disease. The stimulation of angiogenesis by NO might be due to upregulation of local VEGF expression.
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Affiliation(s)
- Tsunetatsu Namba
- Division of Clinical Gene Therapy, Osaka University Medical School, 2-2 Yamada-oka, Suita 565-0871, Osaka, Japan
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26
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Rossi GP, Taddei S, Virdis A, Cavallin M, Ghiadoni L, Favilla S, Versari D, Sudano I, Pessina AC, Salvetti A. The T-786C and Glu298Asp polymorphisms of the endothelial nitric oxide gene affect the forearm blood flow responses of Caucasian hypertensive patients. J Am Coll Cardiol 2003; 41:938-45. [PMID: 12651037 DOI: 10.1016/s0735-1097(02)03011-5] [Citation(s) in RCA: 112] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
OBJECTIVES We sought to investigate whether two polymorphisms located in the promoter (T(-786)C) and exon 7 (Glu298Asp) of the endothelial nitric oxide (NO) synthase (eNOS) gene affected agonists-mediated NO release. BACKGROUND Endothelial dysfunction can be genetically determined. Therefore, we investigated whether two polymorphisms located in the eNOS gene affected agonists-mediated NO release. METHODS We compared endothelial-dependent and -independent vasodilation of the different eNOS genotypes in a cross-sectional study on 187 subjects, of whom 137 were uncomplicated essential hypertensive patients (PH) (49 +/- 9 years, 151 +/- 11/99 +/- 5 mm Hg) and 50 healthy normotensive subjects (NT) (43 +/- 16 years, 123 +/- 10/78 +/- 7 mm Hg). Endothelial-dependent and -independent vasodilation was assessed as the forearm blood flow response to incrementally increasing doses of acetylcholine (0.15, 0.45, 1.5, 4.5, 15 microg/100 ml/min) and sodium nitroprusside (1, 2, 4 microg/100 ml/min), respectively. Genotyping was performed with melting curve analysis (Lightcycler) of polymerase chain reaction products from acceptor (5' end-labeled with LCRed 640) and donor probes (3' end-labeled with fluorescein) specific for each polymorphism. The genotype distribution of T(-786)C (CC = 21.9%, CT = 48.7%, TT = 29.4%) and Glu298Asp (GG = 39.0%, GT =51.9%, TT = 9.1%) was similar in PH and NT. A repeated measure analysis of variance showed a blunting of endothelium-dependent vasodilation in PH compared with NT (p < 0.001). A significant effect of the T(-786)C (p = 0.002) but not of the Glu298Asp (p = NS) eNOS polymorphism on endothelial-dependent vasodilation was found. However, we also detected a significant interaction between the T(-786)C and Glu298Asp polymorphism (p < 0.001). No effect on either polymorphism on endothelial-independent vasodilation was seen. CONCLUSIONS The T(-786)C promoter polymorphism and its interaction with exon 7 Glu298Asp affect endothelium-dependent vasodilation in mild-to-moderate PH patients and NT Caucasian subjects.
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Affiliation(s)
- Gian Paolo Rossi
- Department of Clinical and Experimental Medicine, Clinica Medica 4 University Hospital, University of Padua, via Giustiniani 2, 35126 Padua, Italy.
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27
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Abstract
OBJECTIVE Angiogenesis plays a key role in the growth and function of normal and pathological tissues. We investigated the effect of pulsatile flow on endothelial cell (EC) in vitro angiogenic activity. METHODS AND RESULTS Bovine aortic ECs were exposed to "static" or "flow" (1.2 to 67.0 mL/min, shear stress 1.4 to 19.2 dyne/cm2) conditions for 2 to 24 hours. After exposure, angiogenesis was measured as tubule formation on Matrigel, and EC migration was assessed by filter migration assay. Pulsatile flow increased angiogenesis and EC migration in a temporal and force-dependent manner, with a maximal effect at 16 hours (13.2 dyne/cm2). Pertussis toxin completely inhibited the effect of pulsatile flow on angiogenesis and migration. Transfection of ECs with inhibitory mutants of the alpha subunit of G(i)1 or G(i)3, but not G(i)2, inhibited the flow-induced angiogenic response by 61+/-2% and 32+/-6%, respectively, whereas transfection with constitutively activated mutants of the alpha subunit of G(i)1 or G(i)3, but not G(i)2, increased the flow-induced response by 202+/-23% and 70+/-4%, respectively. In contrast, inhibition of Gbetagamma by the carboxy terminal fragment of beta-adrenergic receptor kinase overexpression increased the flow-induced response by 82+/-8%. CONCLUSIONS These results suggest that pulsatile flow stimulates angiogenesis and that this effect is mediated by activation of G(ialpha)1 or G(ialpha)3, but not Gbetagamma, subunits.
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MESH Headings
- Animals
- Aorta/drug effects
- Aorta/physiology
- Cattle
- Cell Movement/drug effects
- Cell Movement/physiology
- Cyclic AMP-Dependent Protein Kinases/genetics
- Cyclic AMP-Dependent Protein Kinases/physiology
- Endothelium, Vascular/cytology
- Endothelium, Vascular/drug effects
- Endothelium, Vascular/metabolism
- Endothelium, Vascular/physiology
- GTP-Binding Protein alpha Subunit, Gi2
- GTP-Binding Protein alpha Subunits, Gi-Go/genetics
- GTP-Binding Protein alpha Subunits, Gi-Go/physiology
- GTP-Binding Proteins/biosynthesis
- GTP-Binding Proteins/physiology
- Neovascularization, Physiologic/drug effects
- Neovascularization, Physiologic/genetics
- Neovascularization, Physiologic/physiology
- Peptide Fragments/genetics
- Peptide Fragments/physiology
- Proto-Oncogene Proteins/genetics
- Proto-Oncogene Proteins/physiology
- Recombinant Proteins
- Regional Blood Flow/drug effects
- Regional Blood Flow/genetics
- Regional Blood Flow/physiology
- Stress, Mechanical
- Transfection
- Virulence Factors, Bordetella/pharmacology
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Affiliation(s)
- John P Cullen
- Department of Surgery, University of Rochester Medical Center, Rochester, NY 14642-8410, USA
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28
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Loufrani L, Li Z, Lévy BI, Paulin D, Henrion D. Excessive microvascular adaptation to changes in blood flow in mice lacking gene encoding for desmin. Arterioscler Thromb Vasc Biol 2002; 22:1579-84. [PMID: 12377733 DOI: 10.1161/01.atv.0000032652.24932.1a] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVE Desmin, an intermediate filament, has a key role in the integrity of myocytes, and its absence induces cardiomyopathies. Mice lacking desmin (Des-/- group) exhibit microvascular dysfunction leading to smooth muscle hyporeactivity. We investigated the effect of the absence of desmin in mice (Des-/- mice versus Des+/+ mice) on the adaptation of mesenteric arteries to changes in blood flow. METHODS AND RESULTS With the use of selective ligations of second-order mesenteric arteries, blood flow was either diminished (low flow [LF]) or elevated (high flow [HF]); respective LF to HF values were 136+/-18 to 206+/-29 microL/min for Des+/+ mice and 119+/-14 to 189+/-24 microL/min for Des-/-mice in daughter arteries. Two weeks after ligation, arteries were mounted in an arteriograph, allowing the measurement of diameter under controlled conditions of pressure and flow. In HF arteries, diameter changes in response to increases in pressure were higher in Des-/- mice than in Des+/+ mice. Conversely, in LF arteries, diameter was lower in Des-/- mice. Flow-dependent dilation was higher in HF arteries and lower in LF arteries than in control arteries. This adaptation was lower in Des-/- mice than in Des+/+ mice (11.6+/-3.1% versus 25.5+/-4.8% dilation, respectively). Endothelial NO synthase expression increased in HF arteries in both strains. CONCLUSIONS These findings provide a demonstration of the role of the intermediate filament desmin in microvascular remodeling. This dysfunction might take place in desmin-related myopathies.
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MESH Headings
- Adaptation, Physiological/genetics
- Adaptation, Physiological/physiology
- Animals
- Desmin/deficiency
- Desmin/genetics
- Desmin/physiology
- Endothelium, Vascular/metabolism
- Endothelium, Vascular/physiology
- Endothelium, Vascular/surgery
- Ligation/methods
- Male
- Mesenteric Arteries/metabolism
- Mesenteric Arteries/surgery
- Mice
- Mice, Mutant Strains
- Microcirculation/metabolism
- Microcirculation/physiopathology
- Muscle, Smooth, Vascular/blood supply
- Muscle, Smooth, Vascular/physiology
- Muscle, Smooth, Vascular/surgery
- Muscular Diseases/genetics
- Muscular Diseases/physiopathology
- Regional Blood Flow/genetics
- Regional Blood Flow/physiology
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Affiliation(s)
- Laurent Loufrani
- Institut National de la Santé et de la Recherche Médicale U 541, IFR Circulation-Paris-Nord, Paris, France
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29
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Lind L, Sarabi M, Millgård J, Kahan T. Endothelium-dependent vasodilation is impaired in apparently healthy subjects with a family history of myocardial infarction. J Cardiovasc Risk 2002; 9:53-7. [PMID: 11984218 DOI: 10.1177/174182670200900108] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
OBJECTIVES To investigate whether endothelial-dependent vasodilation is altered in healthy subjects with a family history of myocardial infarction. SETTING Tertiary University Hospital SUBJECTS AND DESIGN Fifty apparently healthy subjects selected from the general population were subjected to an evaluation of endothelial-dependent vasodilation (EDV) and endothelial-independent vasodilation (EIDV) by means of local infusion of methacholine (MCh, 2 and 4 microg/min) and sodium nitroprusside (SNP, 5 and 10 microg/min) with measurements of forearm blood flow with venous occlusion plethysmography. The occurrence of plaque and the intima-media thickness of the carotid arteries were determined by ultrasonography. RESULTS Subjects reporting at least one parent suffering from myocardial infarction (n = 11) showed a significantly lower EDV than subjects without such a family history (21 +/- 3.7 vs. 26 +/- 6.7 ml/min/100 ml tissue at MCh 4 microg/min, P<0.05). EIDV was not significantly different between the groups (21 +/- 6.8 vs. 18 +/- 5.4 ml/min/100 ml tissue at SNP 10 microg/min). Age, sex distribution, body mass index, waist to hip ratio, blood pressure, lipids, fasting blood glucose, smoking habits and status of the carotid arteries were not significantly different between the groups. CONCLUSION A family history of myocardial infarction was found to be associated with an impaired endothelial-dependent vasodilation in the forearm of apparently healthy subjects. The risk factor profile was not different from the control group, suggesting that genetic factors are responsible for the impaired endothelial-dependent vasodilation.
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Affiliation(s)
- Lars Lind
- Department of Internal Medicine, University Hospital, Uppsala, Sweden
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30
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Sofowora G, Dishy V, Xie HG, Imamura H, Nishimi Y, Morales CR, Morrow JD, Kim RB, Stein CM, Wood AJ. In-vivo effects of Glu298Asp endothelial nitric oxide synthase polymorphism. Pharmacogenetics 2001; 11:809-14. [PMID: 11740345 DOI: 10.1097/00008571-200112000-00009] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Endothelial nitric oxide synthase catalyses the formation of the vasodilator nitric oxide, a major regulator of vascular tone. The Asp298 polymorphism of the nitric oxide synthase gene is associated with altered function and expression of the enzyme in vitro and myocardial infarction and coronary artery spasm in vivo. We examined the effect of the Glu298Asp polymorphism on: (1) local vascular responses to phenylephrine, acetylcholine, glyceryl trinitrate and prostaglandin E1 in the dorsal hand vein; (2) changes in forearm blood flow during mental stress, a measure of nitric oxide-mediated effect on resistance vessels; (3) excretion of urinary nitrite/nitrate as a measure of total body nitric oxide production; and (4) F2-isoprostane metabolite, a measure of oxidative stress, in healthy Glu298 (n = 12) and Asp298 (n = 13) homozygotes. There were no significant differences in acetylcholine dose responses (P = 0.29) in Glu298 and Asp298 homozygotes. Responses to glyceryl trinitrate, prostaglandin E1 and the alpha-adrenergic agonist phenylephrine did not differ by genotype. Forearm blood flow was similar at rest and increased significantly (from 7.5 ml/min/100 ml to 12.2 ml/min/100 ml; P = 0.003), but similarly (P = 0.2), during mental stress in both genotypes. Asp298 homozygotes excreted significantly less nitrate/nitrite than Glu298 homozygotes (nitrate + nitrite/creatinine ratio 0.05 +/- 0.01 vs. 0.09 +/- 0.01, respectively; P < 0.005). Urinary F2-isoprostane metabolite excretion did not differ (Glu298, 2.04 +/- 0.25 ng/mg creatinine; Asp298, 1.85 +/- 0.37 ng/mg creatinine; P = 0.7). We conclude that in healthy volunteers the Glu298Asp polymorphism affects endogenous nitric oxide production without affecting nitric oxide-mediated vascular responses. This polymorphism may only have clinical significance in the presence of endothelial dysfunction.
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Affiliation(s)
- G Sofowora
- Division of Clinical Pharmacology, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-6602, USA
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31
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Iwatate M, Miura T, Ikeda Y, Kawamura S, Dairaku Y, Okamura T, Kimura M, Yamaguchi K, Ueno H, Matsuzaki M. Effects of in vivo gene transfer of fibroblast growth factor-2 on cardiac function and collateral vessel formation in the microembolized rabbit heart. Jpn Circ J 2001; 65:226-31. [PMID: 11266199 DOI: 10.1253/jcj.65.226] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The effects of gene transfer of the secreted form of fibroblast growth factor-2 (FGF-2) were tested using an adenovirus vector in the microembolized rabbit heart. Japanese white rabbits underwent an intracoronary injection of 25-microm microspheres followed by recombinant adenovirus vectors encoding a secreted form of FGF-2 (FGF group), LacZ (LacZ group), or saline (saline group). Left ventricular (LV) systolic function was serially assessed by echocardiography. Vascular density was measured at 14 days with Azan and CD31 staining. The development of collateral vessels was assessed by measuring myocardial blood flow before and after the occlusion of the left anterior descending coronary artery. Percent fractional shortening (%FS) decreased after the microembolization, and improved gradually for 14 days in the FGF group only (41+/-1% (FGF) vs 32+/-1% (LacZ), 31+/-1% (saline), p<0.01). The vascular density and myocardial collateral blood flow were significantly higher in the FGF group in comparison with other groups. Transcoronary arterial gene transfer of the secreted form of FGF-2 was beneficial for the recovery of LV systolic function and development of collateral vessels in the microembolized rabbit heart.
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Affiliation(s)
- M Iwatate
- Department of Medical Bioregulation, Yamaguchi University School of Medicine, Ube, Japan
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32
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Emanueli C, Minasi A, Zacheo A, Chao J, Chao L, Salis MB, Straino S, Tozzi MG, Smith R, Gaspa L, Bianchini G, Stillo F, Capogrossi MC, Madeddu P. Local delivery of human tissue kallikrein gene accelerates spontaneous angiogenesis in mouse model of hindlimb ischemia. Circulation 2001; 103:125-32. [PMID: 11136697 DOI: 10.1161/01.cir.103.1.125] [Citation(s) in RCA: 128] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
BACKGROUND Human tissue kallikrein (HK) releases kinins from kininogen. We investigated whether adenovirus-mediated HK gene delivery is angiogenic in the context of ischemia. METHODS AND RESULTS Hindlimb ischemia, caused by femoral artery excision, increased muscular capillary density (P:<0.001) and induced the expression of kinin B(1) receptor gene (P:<0.05). Pharmacological blockade of B(1) receptors blunted ischemia-induced angiogenesis (P:<0.01), whereas kinin B(2) receptor antagonism was ineffective. Intramuscular delivery of adenovirus containing the HK gene (Ad. CMV-cHK) enhanced the increase in capillary density caused by ischemia (969+/-32 versus 541+/-18 capillaries/mm(2) for control, P:<0.001), accelerated blood flow recovery (P:<0.01), and preserved energetic charge of ischemic muscle (P:<0.01). Chronic blockade of kinin B(1) or B(2) receptors prevented HK-induced angiogenesis. CONCLUSIONS HK gene delivery enhances the native angiogenic response to ischemia. Angiogenesis gene therapy with HK might be applicable to peripheral occlusive vascular disease.
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MESH Headings
- Adenoviridae/genetics
- Animals
- Bradykinin Receptor Antagonists
- Capillaries/cytology
- Capillaries/drug effects
- Capillaries/metabolism
- Disease Models, Animal
- Gene Expression
- Genetic Therapy/methods
- Hindlimb/blood supply
- Hindlimb/drug effects
- Humans
- Immunohistochemistry
- Injections, Intramuscular
- Ischemia/genetics
- Ischemia/pathology
- Ischemia/therapy
- Male
- Mice
- Muscle, Skeletal/blood supply
- Muscle, Skeletal/drug effects
- Muscle, Skeletal/metabolism
- Muscle, Skeletal/pathology
- Neovascularization, Physiologic/drug effects
- Neovascularization, Physiologic/genetics
- Peripheral Vascular Diseases/therapy
- Receptor, Bradykinin B1
- Receptor, Bradykinin B2
- Receptors, Bradykinin/metabolism
- Regional Blood Flow/drug effects
- Regional Blood Flow/genetics
- Reverse Transcriptase Polymerase Chain Reaction
- Tissue Kallikreins/administration & dosage
- Tissue Kallikreins/genetics
- Transgenes/genetics
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Affiliation(s)
- C Emanueli
- Laboratorio di Patologia Vascolare, Istituto Dermopatico dell'Immacolata, Rome, Italy
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33
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Hoit BD, Suresh DP, Craft L, Walsh RA, Liggett SB. beta2-adrenergic receptor polymorphisms at amino acid 16 differentially influence agonist-stimulated blood pressure and peripheral blood flow in normal individuals. Am Heart J 2000; 139:537-42. [PMID: 10689270 DOI: 10.1016/s0002-8703(00)90099-1] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
BACKGROUND The Gly16 beta(2)-adrenergic receptor (beta(2)AR) polymorphism is a common variant of the beta(2)AR that displays depressed function caused by enhanced receptor downregulation in vitro compared with the Arg16 receptor. METHODS AND RESULTS We studied 20 healthy, normotensive, nonsmoking white individuals who were homozygous for either the Arg16 (n = 10) or the Gly16 (n = 10) genotype. Plethysmographic lower-limb blood flow, blood pressure, and 2-dimensional echocardiograms were recorded at baseline and after 15-minute incremental infusions of terbutaline (100 to 300 ng/kg per minute). Baseline heart rates, blood pressures, and flows were similar in both groups, but at the maximum dose of terbutaline, limb blood flow was less (P <.05), calculated vascular resistance was greater (P <.05), and systolic and diastolic blood pressures were greater in patients with Gly16 than in those with Arg16 (both P <.05). In contrast, terbutaline-stimulated heart rates were not different. In a separate group of 20 homozygous individuals (12 Arg16, 8 Gly16), there were no differences in 2-dimensional echocardiographically determined ventricular function. CONCLUSIONS We conclude that the Gly16 beta(2)AR polymorphism imparts attenuated vasodilatory responses to catecholamines in normal human beings and is an important genetic component in the regulation of peripheral blood flow and systemic arterial pressure.
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Affiliation(s)
- B D Hoit
- Division of Cardiology and the Departments of Medicine and Pharmacology, University of Cincinnati, Ohio, USA.
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34
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Abstract
Low oxygen tension (hypoxia) is an important prognostic factor in cancer treatment because it affects tumor formation and malignant progression. Many genes governing these complex processes have been found to be oxygen regulated. This article reviews the present knowledge of hypoxia-inducible gene expression and how this affects angiogenesis, progression, and metastasis. Of particular importance are hypoxia-regulated transcription factors because they can modulate expression of countless different genes. Additional genes analyzed in some detail include those encoding angiogenic growth factors, factors controlling blood flow, and those involved in metastasis. Although hypoxia is generally perceived as a hindrance to cancer therapy, it is possibly exploitable because severe oxygen deficiency is tumor specific. Strategies aimed at using the presence of hypoxia in solid tumors include oxygen sensitive chemotherapy and gene therapy.
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Affiliation(s)
- G U Dachs
- Gray Laboratory Cancer Research Trust, Mount Vernon Hospital, Northwood, UK
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