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Carey RM. Pathophysiology of Primary Hypertension. Microcirculation 2008. [DOI: 10.1016/b978-0-12-374530-9.00020-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Wang B, Zhang JD, Feng JB, Yin HQ, Liu FY, Wang Y. Improvement of vascular remodeling in spontaneous hypertensive rats with traditional Chinese medicine. Clin Exp Hypertens 2007; 29:345-55. [PMID: 17653968 DOI: 10.1080/10641960701500612] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Qin-Dan-Jiang-Ya-Tang (QDJYT) is a traditional Chinese herbal medicine for the treatment of hypertension. The effect of QDJYT on blood pressure (BP) and vascular remodeling in hypertension was investigated in the model of spontaneous hypertensive rats (SHR). Sixteen SHRs were divided into two groups: the SHR group and the SHR+ QDJYT group. Eight Wistar-Kyoto (WKY) rats were in the normal control group. QDJYT (750 mg/kg) was orally administered daily for 12 weeks to the SHR+QDJYT group. After 12 weeks, thoracic aortas were segregated. The media thickness (MT) and the lumen diameter (LD) of the aortic wall, the ratios of MT to LD, the expression of basic fibroblast growth factor (bFGF) mRNA, and the level of its proteinic production were examined by histology, real-time PCR, and Western blot analysis, respectively. It was observed in our study that MT, MT/LD, the expression of bFGF mRNA, and the level of its proteinic production in aortic walls were higher in SHRs than in WKY rats. However, in the SHRs treated with QDJYT, we found MT, MT/LD, the expression of bFGF mRNA and the level of its proteinic production were lower than SHRs. These results suggest that QDJYT can improve the vascular remodeling in SHRs, and the mechanisms may be related to the suppressive effect of QDJYT on bFGF mRNA and its proteic productions in the aortic walls of SHRs.
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Affiliation(s)
- Bo Wang
- Department of Traditional Chinese Medicine, Qilu Hospital Affiliated with Shandong University, Jinan, China
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Khan R, Sheppard R. Fibrosis in heart disease: understanding the role of transforming growth factor-beta in cardiomyopathy, valvular disease and arrhythmia. Immunology 2006; 118:10-24. [PMID: 16630019 PMCID: PMC1782267 DOI: 10.1111/j.1365-2567.2006.02336.x] [Citation(s) in RCA: 384] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
The importance of fibrosis in organ pathology and dysfunction appears to be increasingly relevant to a variety of distinct diseases. In particular, a number of different cardiac pathologies seem to be caused by a common fibrotic process. Within the heart, this fibrosis is thought to be partially mediated by transforming growth factor-beta1 (TGF-beta1), a potent stimulator of collagen-producing cardiac fibroblasts. Previously, TGF-beta1 had been implicated solely as a modulator of the myocardial remodelling seen after infarction. However, recent studies indicate that dilated, ischaemic and hypertrophic cardiomyopathies are all associated with raised levels of TGF-beta1. In fact, the pathogenic effects of TGF-beta1 have now been suggested to play a major role in valvular disease and arrhythmia, particularly atrial fibrillation. Thus far, medical therapy targeting TGF-beta1 has shown promise in a multitude of heart diseases. These therapies provide great hope, not only for treatment of symptoms but also for prevention of cardiac pathology as well. As is stated in the introduction, most reviews have focused on the effects of cytokines in remodelling after myocardial infarction. This article attempts to underline the significance of TGF-beta1 not only in the post-ischaemic setting, but also in dilated and hypertrophic cardiomyopathies, valvular diseases and arrhythmias (focusing on atrial fibrillation). It also aims to show that TGF-beta1 is an appropriate target for therapy in a variety of cardiovascular diseases.
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Affiliation(s)
- Razi Khan
- McGill University, Faculty of Medicine, Montreal, Quebec, Canada.
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Yusa J, Fukuda N, Sato S, Matsmoto K, Mugishima H, Kamoi K. Inhibition of growth of human gingival fibroblasts by chimeric DNA-RNA hammerhead ribozyme targeting transforming growth factor-beta 1. J Periodontol 2005; 76:1265-74. [PMID: 16101357 DOI: 10.1902/jop.2005.76.8.1265] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
BACKGROUND Transforming growth factor (TGF)-beta1 is involved in the pathogenesis of both drug-induced gingival overgrowth and hereditary gingival fibromatosis. Ribozymes enzymatically cleave target mRNAs and are expected to be utilized as the basis of novel nucleic acid-based therapies. We designed a chimeric DNA-RNA ribozyme targeting TGF-beta1 mRNA and examined its effect on growth of gingival fibroblasts in culture. METHODS Chimeric DNA-RNA hammerhead ribozyme with sequence complementary to the loop structure of human TGF-beta1 mRNA was used. We evaluated transfer of the chimeric ribozyme by hemagglutinating virus of Japan (HVJ)-envelope into cultured human gingival fibroblasts in vitro and rat gingival tissues in vivo. We then examined effects of the chimeric ribozyme to TGF-beta1 on proliferation and DNA synthesis in human gingival fibroblasts. We also examined effects of the chimeric ribozyme to TGF-beta1 on expression of TGF-beta1, type IV collagens, and fibronectin mRNAs and expression of TGF-beta1 protein in human gingival fibroblasts. RESULTS Chimeric ribozyme was sufficiently distributed into human fibroblasts in vitro and rat gingivae in vivo. Chimeric ribozyme to TGF-beta1 significantly inhibited expression of TGF-beta1, type IV collagen, and fibronectin mRNAs and TGF-beta1 protein in human gingival fibroblasts. Mismatch ribozyme had no effect on expression of these molecules. Chimeric ribozyme to TGF-beta1 also significantly inhibited proliferation and DNA synthesis in gingival fibroblasts. CONCLUSION Chimeric DNA-RNA ribozyme targeting TGF-beta1 may be a useful gene therapy agent for treatment of gingival hyperplasia.
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Affiliation(s)
- Junko Yusa
- Department of Periodontology, The Nippon Dental University, School of Dentistry, Tokyo, Japan
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Xiong C, Mou Y, Zhang J, Fu M, Chen YE, Akinbami MA, Cui T. Impaired expression of PPAR gamma protein contributes to the exaggerated growth of vascular smooth muscle cells in spontaneously hypertensive rats. Life Sci 2005; 77:3037-48. [PMID: 15970297 DOI: 10.1016/j.lfs.2005.02.032] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2004] [Accepted: 02/09/2005] [Indexed: 11/17/2022]
Abstract
Peroxisome proliferator-activated receptor gamma (PPAR gamma), a member of the nuclear receptor family, has been implicated in the regulation of vascular smooth muscle cell (VSMC) growth; however, the underlying mechanisms are still not fully understood. We hypothesized that PPAR gamma functional deficiency may contribute to the enhanced proliferation of VSMC associated with hypertension in spontaneously hypertensive rats (SHR). We observed that PPAR gamma mRNA level in SHR VSMC was 3 approximately 4 fold higher than that from Wistar-Kyoto rats (WKY), but the protein expression levels of PPAR gamma are significantly lower in SHR than WKY VSMC, suggesting an impaired control of PPAR gamma protein expression in SHR VSMC. The deficiency of PPAR gamma protein expression in SHR VSMC was demonstrated by PPAR gamma reporter gene assays. Furthermore, the exaggerated growth of SHR VSMC was markedly attenuated by adenoviral PPAR gamma overexpression. Taken together, our results provided the first direct evidence that impaired expression of PPAR gamma protein contributes to the exaggerated growth of SHR VSMC.
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MESH Headings
- Adenoviridae/genetics
- Animals
- Aorta/metabolism
- Arteries/metabolism
- Blood Pressure
- Blotting, Northern
- Blotting, Western
- Cell Proliferation
- Cells, Cultured
- Genes, Reporter
- Hypertension/genetics
- Hypertension/metabolism
- Hypertension/physiopathology
- Immunoenzyme Techniques
- Male
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/metabolism
- PPAR gamma/genetics
- PPAR gamma/metabolism
- RNA, Messenger/metabolism
- Rats
- Rats, Inbred SHR
- Rats, Inbred WKY
- Transfection
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Affiliation(s)
- Chen Xiong
- Cardiovascular Research Institute, Morehouse School of Medicine, 720 Westview Drive SW, Atlanta, GA 30310, Georgia, USA
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Schiffrin EL, Touyz RM. From bedside to bench to bedside: role of renin-angiotensin-aldosterone system in remodeling of resistance arteries in hypertension. Am J Physiol Heart Circ Physiol 2004; 287:H435-46. [PMID: 15277186 DOI: 10.1152/ajpheart.00262.2004] [Citation(s) in RCA: 185] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Ernesto L Schiffrin
- Canadian Institutes of Health Research Multidisciplinary Research Group on Hypertension and Hypertension Clinic, Clinical Research Institute of Montréal, Quebec, Canada H2W 1R7.
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Fukuda N, Furuya R, Kishioka H, Suzuki R, Matsuda H, Tahira Y, Takagi H, Ikeda Y, Saito S, Matsumoto K, Kanmatsuse K. Effects of antisense peptide nucleic acid to platelet-derived growth factor A-chain on growth of vascular smooth muscle cells. J Cardiovasc Pharmacol 2003; 42:224-31. [PMID: 12883326 DOI: 10.1097/00005344-200308000-00011] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
To investigate antisense peptide nucleic acid (PNA) as a gene therapy for the arterial proliferative diseases, the authors designed and examined the effects of an antisense PNA targeting platelet-derived growth factor (PDGF) A-chain on expression of PDGF A-chain and growth of vascular smooth muscle cells (VSMCs) from spontaneously hypertensive rats. A 15-mer antisense PNA complementary to the initiation codon of rat and human PDGF A-chain mRNA was synthesized and purified by high-performance liquid chromatography. Gel-shift assay and biomolecular interaction analysis (BIAcore) revealed that the antisense PNA bound weakly to the target RNA, whereas it bound strongly to the target DNA. Fluorescein-isothiocyanate-labeled antisense PNA to PDGF A-chain was taken up slowly and maintained in VSMCs for a prolonged period of time. Antisense PNA inhibited expression of PDGF A-chain mRNA and protein as well as DNA synthesis in VSMCs in a dose-independent manner. Inhibition of DNA synthesis by the antisense PNA was greater than that by the antisense DNA at a low concentration (0.5 micromol/L). These results suggest that antisense PNA to PDGF A-chain will be used as a gene therapy for vascular proliferative diseases such as hypertensive vascular diseases, restenosis of coronary arteries after angioplasty, and atherosclerosis.
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Affiliation(s)
- Noboru Fukuda
- Second Department of Internal Medicine, Nihon University School of Medicine, Ooyaguchi-kami 30-1, Itabashi-ku, Tokyo 173-8610, Japan.
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Su JZ, Fukuda N, Jin XQ, Lai YM, Suzuki R, Tahira Y, Takagi H, Ikeda Y, Kanmatsuse K, Miyazaki H. Effect of AT2 receptor on expression of AT1 and TGF-beta receptors in VSMCs from SHR. Hypertension 2002; 40:853-8. [PMID: 12468569 DOI: 10.1161/01.hyp.0000042096.17141.b1] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
We recently reported that overexpression of the angiotensin II type 2 (AT2) receptor downregulates the AT1a receptor through the bradykinin/NO pathway in a ligand-independent manner in vascular smooth muscle cells (VSMCs). In the present study, we investigated the effect of AT2 receptor overexpression on the expression of the AT1a receptor and transforming growth factor-beta (TGF-beta) receptor subtypes in VSMCs from spontaneously hypertensive rats (SHR) and Wistar-Kyoto rats (WKY). Transfection of the AT2 receptor gene downregulated expression of the AT1a receptor in VSMCs from WKY, but did not affect expression of the AT1a receptor in VSMCs from SHR. Transfection of the AT2 receptor abolished DNA synthesis in response to angiotensin II in VSMCs from WKY; in VSMCs from SHR, basal DNA synthesis was suppressed, but DNA synthesis in response to Ang II was not altered. The NO substrate L-arginine augmented downregulation of the AT1a receptor in VSMCs from WKY, whereas it did not affect expression of the AT1a receptor in VSMCs from SHR. In response to AT2 receptor transfection, expression of TGF-beta type I receptor mRNA was suppressed significantly in VSMCs from WKY, whereas expression of TGF-beta type I receptor was not altered in VSMCs from SHR. These results suggest that the AT2 receptor downregulates AT1a and TGF-beta type I receptors in normal VSMCs, but not in SHR-derived VSMCs. The lack of downregulation of the AT1a receptor may contribute, in part, to the exaggerated growth of VSMCs from SHR.
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MESH Headings
- Activin Receptors, Type I/biosynthesis
- Activin Receptors, Type I/genetics
- Animals
- Arginine/pharmacology
- Cells, Cultured
- DNA/biosynthesis
- Down-Regulation/physiology
- Gene Expression/drug effects
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/metabolism
- Protein Serine-Threonine Kinases
- RNA, Messenger/metabolism
- Rats
- Rats, Inbred SHR
- Rats, Inbred WKY
- Receptor, Angiotensin, Type 1
- Receptor, Angiotensin, Type 2
- Receptor, Transforming Growth Factor-beta Type I
- Receptor, Transforming Growth Factor-beta Type II
- Receptors, Angiotensin/biosynthesis
- Receptors, Angiotensin/genetics
- Receptors, Transforming Growth Factor beta/biosynthesis
- Receptors, Transforming Growth Factor beta/genetics
- Transfection
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Affiliation(s)
- Jin-Zi Su
- Second Department of Internal Medicine, Nihon University School of Medicine, Tokyo, Japan
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Tahira Y, Fukuda N, Endo M, Suzuki R, Ikeda Y, Takagi H, Matsumoto K, Kanmatsuse K. Transforming growth factor-beta expression in cardiovascular organs in stroke-prone spontaneously hypertensive rats with the development of hypertension. Hypertens Res 2002; 25:911-8. [PMID: 12484516 DOI: 10.1291/hypres.25.911] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Transforming growth factor (TGF)-beta activity is involved in several cardiovascular diseases owing to its effects on the growth of vascular smooth muscle cells and induction of extracellular matrix formation. We evaluated expression of TGF-beta in cardiovascular organs from stroke-prone spontaneously hypertensive rats (SHR-SP) which show severe cardiovascular damages with the development of hypertension. Twelve-week-old Wistar-Kyoto (WKY)/Izm rats and SHR-SP/Izm were loaded with 1% salt for 4 weeks. Aorta, heart and kidney were removed and evaluated histologically by hematoxylin-eosin staining. Expression of TGF-beta1 mRNA was evaluated by reverse transcription and polymerase chain reaction analysis in mRNA extracted with oligo dT-cellulose. Expression of TGF-beta1 protein was evaluated by Western blot analysis and immunohistochemical study in renal cortex. Whereas expression of TGF-beta1 mRNA was detected only in the heart of SHR-SP before salt loading, it was detected in the aorta, left ventricle of heart and renal cortex from both rat strains, and it was stronger in the renal cortex of SHR-SP than in the renal cortex of WKY rats. Expression of TGF-beta1 protein was markedly higher in the renal cortex of SHR-SP than in the renal cortex of WKY rats after salt loading. TGF-beta was localized at glomeruli and capillary arteries in the renal cortex, and immunostaining was stronger in SHR-SP than in WKY rats. Expression of TGF-beta1 was increased in glomeruli and capillaries of the renal cortex with the development of hypertension in SHR-SP. These results implicate TGF-beta in the renal damage observed in hypertension.
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Affiliation(s)
- Yoshiko Tahira
- Second Department of Internal Medicine, Nihon University School of Medicine, Tokyo 173-8610, Japan
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Fukuda N, Hu WY, Teng J, Chikara S, Nakayama M, Kishioka H, Kanmatsuse K. Troglitazone inhibits growth and improves insulin signaling by suppression of angiotensin II action in vascular smooth muscle cells from spontaneously hypertensive rats. Atherosclerosis 2002; 163:229-39. [PMID: 12052469 DOI: 10.1016/s0021-9150(02)00014-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Troglitazone, a thiazolizidinedione, has recently been reported to possess anti-arteriosclerotic properties. To evaluate mechanisms underlying the anti-arteriosclerotic effects of troglitazone, we examined the effect of troglitazone on growth, expression of growth factors, and insulin signaling in vascular smooth muscle cells (VSMC) from spontaneously hypertensive rats (SHR) which produce angiotensin II (Ang II) in a homogeneous culture. Troglitazone inhibited basal and serum-stimulated DNA synthesis and inhibited increases in the number of VSMC from SHR and normotensive Wistar-Kyoto (WKY) rats. Its inhibition was greater in VSMC from SHR. Troglitazone abolished DNA synthesis in response to Ang II in VSMC from both rat strains and markedly inhibited DNA synthesis in response to epidermal growth factor (EGF) and platelet-derived growth factor (PDGF)-AA in VSMC from SHR. Troglitazone did not alter the expression of transforming growth factor (TGF)-beta1, PDGF A-chain, or basic fibroblast growth factor (bFGF) mRNAs in VSMC from WKY rats, but it markedly decreased expression of these growth factor mRNAs in VSMC from SHR. Troglitazone markedly decreased basal and Ang II-stimulated expression of extracellular signal-regulated kinase proteins in VSMC from both rat strains. Troglitazone abolished Ang II-induced suppression of phosphatidilinositol 3-kinase (PI3-kinase) activity, insulin receptor substrate-1 (IRS-1) associated tyrosine phosphorylation, and IRS-1 associated p85 levels in VSMC from WKY rats. Basal PI3-kinase activity, tyrosine phosphorylation of IRS-1, and IRS-1 associated p85 levels were lower in VSMC from SHR than in cells from WKY rats. Troglitazone significantly increased PI3-kinase activity, IRS-1 associated tyrosine phosphorylation, and IRS-1 associated p85 levels in VSMC from SHR. These results indicate that troglitazone produce its anti-arteriosclerotic effects through suppression of the action of growth-promoting factors including Ang II, and that troglitazone inhibits Ang II-induced suppression of insulin signaling in VSMC from SHR, suggesting that tissue Ang II may lead to insulin resistance and to arteriosclerosis in hypertension. Troglitazone may be useful in the treatment of insulin resistance as well as of hypertensive vascular diseases.
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Affiliation(s)
- Noboru Fukuda
- Second Department of Internal Medicine, Nihon University School of Medicine, Ooyaguchi-kami 30-1, Itabashi-ku, Tokyo 173-8610, Japan.
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Su JZ, Fukuda N, Kishioka H, Hu WY, Kanmatsuse K. Etidronate influences growth and phenotype of rat vascular smooth muscle cells. Pharmacol Res 2002; 46:7-13. [PMID: 12208115 DOI: 10.1016/s1043-6618(02)00041-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Bisphosphonates have been reported to exhibit antiarteriosclerotic and anticalcification effects. We investigated the effect of a bisphosphonate, etidronate, on growth and phenotype of vascular smooth muscle cells (VSMC) from spontaneously hypertensive rats (SHR). Etidronate (10 microM) significantly decreased DNA synthesis evaluated by [3H]thymidine incorporation in VSMC cultured without serum, and 1 microM etidronate significantly inhibited DNA synthesis in the presence of 10% calf serum. Etidronate (10 microM) significantly inhibited VSMC proliferation after 72h incubation. Etidronate (100 microM) significantly increased the expression of SM22alpha mRNA and protein in VSMC, while 10 microM etidronate significantly decreased the expression of matrix Gla mRNA. These findings indicate that etidronate inhibits the exaggerated growth of VSMC from SHR, while altering their phenotype from synthetic to contractile one. These effects of etidronate may account for its antiarteriosclerotic action.
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MESH Headings
- Animals
- Cells, Cultured
- Dose-Response Relationship, Drug
- Etidronic Acid/pharmacology
- Gene Expression Regulation/drug effects
- Gene Expression Regulation/physiology
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/growth & development
- Muscle, Smooth, Vascular/metabolism
- Phenotype
- RNA, Messenger/biosynthesis
- Rats
- Rats, Inbred SHR
- Rats, Inbred WKY
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Affiliation(s)
- Jin-Zi Su
- Second Department of Internal Medicine, Nihon University School of Medicine, Tokyo, Japan
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Hu WY, Fukuda N, Kanmatsuse K. Growth characteristics, angiotensin II generation, and microarray-determined gene expression in vascular smooth muscle cells from young spontaneously hypertensive rats. J Hypertens 2002; 20:1323-33. [PMID: 12131529 DOI: 10.1097/00004872-200207000-00019] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND We have demonstrated that vascular smooth muscle cells (VSMCs) derived from spontaneously hypertensive rats (SHR) show exaggerated growth and produce angiotensin (Ang) II and growth factors. These may reflect intrinsic abnormalities in SHR that are not caused by excessive blood pressure, and are associated with genetic abnormalities. OBJECTIVE To evaluate whether these characteristics of VSMCs from SHR are associated with hypertension or genetic factors. DESIGN AND METHODS VSMCs were obtained by an explant method from aortas of 4-week-old male SHR/Izumo and Wistar-Kyoto (WKY)/Izumo rats. We evaluated growth characteristics by [3H]thymidine incorporation and cell number increases, immunofluorescence of alpha-smooth muscle (alpha-SM) actin, mRNA expressions of phenotype markers, Ang II-generating system components, and growth factors by reverse transcription and polymerase chain reaction analysis, and Ang II levels by radioimmunoassay in VSMCs. Expression of 850 genes in VSMCs was evaluated by microarray. RESULTS VSMCs from young SHR showed increased basal DNA synthesis and higher responses of DNA synthesis and cell numbers in response to calf serum. Ang II was significantly increased in conditioned medium and cell extracts from SHR-derived VSMCs than in those from WKY rat-derived VSMCs. mRNA expression of Ang II-generating proteinases, such as cathepsin D and angiotensin-converting enzyme, was greater in VSMCs from SHRs than in cells from WKY rats. Expression of transforming growth factor-beta1, platelet-derived growth factor A-chain and basic fibroblast growth factor mRNAs was greater in VSMCs from SHRs than in cells from WKY rats. Expression of mRNAs of phenotype markers, such as matrix gamma-carboxyglutamic acid (Gla) and osteopontin, was also greater in VSMCs from SHR than in cells from WYK rats. Microarray study showed that VSMCs derived from young SHR increasingly express genes for many enzymes, adhesion molecules and cytokines. CONCLUSION This study determined that VSMCs derived from young SHR show exaggerated growth, produce Ang II and increasingly express several enzymes, adhesion molecules and cytokines, which are independent of hypertension and possibly associated with genetic abnormalities.
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MESH Headings
- Age Factors
- Angiotensin II/biosynthesis
- Angiotensin II/genetics
- Animals
- Blood Pressure/physiology
- Disease Models, Animal
- Gene Expression Profiling/methods
- Genetic Markers/genetics
- Genetic Predisposition to Disease/genetics
- Intercellular Signaling Peptides and Proteins/genetics
- Male
- Models, Cardiovascular
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/physiology
- Myocytes, Smooth Muscle/physiology
- Oligonucleotide Array Sequence Analysis/methods
- Phenotype
- RNA, Messenger/genetics
- Rats
- Rats, Inbred SHR/genetics
- Rats, Inbred SHR/growth & development
- Rats, Inbred WKY
- Systole/physiology
- Transcription, Genetic/genetics
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Affiliation(s)
- Wen-Yang Hu
- Second Department of Internal Medicine, Nihon University School of Medicine, Tokyo, Japan
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14
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Hu WY, Fukuda N, Kotani M, Kanmatsuse K. Adenovirus-mediated transfer of ribozyme targeting platelet-derived growth factor A-chain mRNA inhibits growth of vascular smooth muscle cells from spontaneously hypertensive rats. J Cardiovasc Pharmacol 2002; 39:858-65. [PMID: 12021580 DOI: 10.1097/00005344-200206000-00011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Platelet-derived growth factor (PDGF) is a potent stimulator of growth of vascular smooth muscle cells (VSMCs). VSMCs from spontaneously hypertensive rats (SHRs) show exaggerated growth and increasingly express PDGF A-chain messenger RNA (mRNA). To examine adenovirus-mediated transfer of a ribozyme targeting the PDGF A-chain mRNA as a possible gene therapy for vascular proliferative diseases, a recombinant adenovirus vector encoding a ribozyme that targets rat PDGF A-chain mRNA (Ad. ribozyme) was designed and synthesized and its effect on the growth of VSMCs from SHRs was investigated. This vector dose-dependently inhibited DNA synthesis in VMSCs from SHRs, whereas an adenovirus vector encoding the Escherichia coli LacZ gene (Ad. LacZ) did not affect DNA synthesis. Ad. ribozyme significantly suppressed proliferation of VSMCs from SHRs in a dose-dependent manner. Ad. LacZ had no effect. Ad. ribozyme significantly inhibited expression of PDGF A-chain mRNA and PDGF-AA protein in VSMCs from SHRs. Ad. LacZ had no effect. These results demonstrated that adenovirus-mediated transfer of a ribozyme targeting the PDGF A-chain mRNA effectively and specifically inhibited the growth of VSMCs from SHRs with suppression of PDGF A-chain mRNA and PDGF-AA protein expression. Adenovirus-mediated transfer of ribozyme targeting PDGF A-chain mRNA may be a feasible gene therapy for vascular proliferative diseases.
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MESH Headings
- Adenoviridae/genetics
- Animals
- Cell Division/drug effects
- Cell Division/genetics
- Drug Delivery Systems/methods
- Gene Transfer Techniques/statistics & numerical data
- Genetic Therapy/methods
- Genetic Therapy/statistics & numerical data
- Genetic Vectors/administration & dosage
- Growth Inhibitors/genetics
- Growth Inhibitors/pharmacology
- Growth Inhibitors/physiology
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/metabolism
- Platelet-Derived Growth Factor/antagonists & inhibitors
- Platelet-Derived Growth Factor/biosynthesis
- Platelet-Derived Growth Factor/genetics
- RNA, Catalytic/administration & dosage
- RNA, Catalytic/genetics
- RNA, Messenger/antagonists & inhibitors
- RNA, Messenger/biosynthesis
- RNA, Messenger/genetics
- Rats
- Rats, Inbred SHR
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Affiliation(s)
- Wen-Yang Hu
- Second Department of Internal Medicine, Nihon University School of Medicine, Itabashi-ku, Tokyo, Japan
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Teng J, Fukuda N, Suzuki R, Takagi H, Ikeda Y, Tahira Y, Kanmatsuse K. Inhibitory effect of a novel angiotensin II type 1 receptor antagonist RNH-6270 on growth of vascular smooth muscle cells from spontaneously hypertensive rats: different anti-proliferative effect to angiotensin-converting enzyme inhibitor. J Cardiovasc Pharmacol 2002; 39:161-71. [PMID: 11791001 DOI: 10.1097/00005344-200202000-00002] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The current study was undertaken to evaluate the anti-proliferative effect of a novel angiotensin II type 1 (AT1) receptor antagonist, RNH-6270, on exaggerated growth of vascular smooth muscle cells (VSMC) from spontaneously hypertensive rats (SHR), in comparison with the effects of an angiotensin-converting enzyme (ACE) inhibitor. RNH-6270 and temocapril significantly inhibited basal DNA synthesis in VSMCs from SHRs in a dose-dependent manner, but not in cells from Wistar-Kyoto (WKY) rats. SHR-derived VSMC showed a hyperresponse of DNA synthesis to serum and angiotensin II compared with that of WKY rats-derived VSMC. RNH-6270 did not affect serum-stimulated DNA synthesis in VSMCs from both rat strains. RNH-6270 abolished angiotensin II-stimulated DNA synthesis in VSMC from both rat strains. RNH-6270 significantly inhibited proliferation of VSMC from both rat strains, but the ACE inhibitor temocapril did not exert such an effect. RNH-6270 decreased the specific binding of angiotensin II to VSMC in a competitive manner for angiotensin II receptors in both rat strains. RNH-6270 and temocapril significantly decreased the expression of growth factor mRNAs and proteins in VSMC from SHR, but not in cells from WKY rats. These results suggest that RNH-6270 is a potent AT1 receptor antagonist and has anti-proliferative effects on VSMCs from SHR, which was not seen with an ACE inhibitor. The growth inhibitory effect of RNH-6270 may be associated with the inhibition of growth factors via antagonism to AT1 receptors.
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MESH Headings
- Angiotensin II/metabolism
- Angiotensin Receptor Antagonists
- Angiotensin-Converting Enzyme Inhibitors/pharmacology
- Animals
- Blotting, Western
- Cell Division/drug effects
- Cells, Cultured
- Fibroblast Growth Factor 2/genetics
- Fibroblast Growth Factor 2/metabolism
- Imidazoles/pharmacology
- Male
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/drug effects
- Platelet-Derived Growth Factor/genetics
- Platelet-Derived Growth Factor/metabolism
- RNA, Messenger/metabolism
- Radioligand Assay
- Rats
- Rats, Inbred SHR
- Rats, Inbred WKY
- Receptor, Angiotensin, Type 1
- Receptors, Angiotensin/metabolism
- Reverse Transcriptase Polymerase Chain Reaction
- Tetrazoles/pharmacology
- Thiazepines/pharmacology
- Transforming Growth Factor beta/genetics
- Transforming Growth Factor beta/metabolism
- Transforming Growth Factor beta1
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Affiliation(s)
- Jian Teng
- Second Department of Internal Medicine, Nihon University School of Medicine, Tokyo, Japan
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16
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Lai YM, Fukuda N, Su JZ, Suzuki R, Ikeda Y, Takagi H, Tahira Y, Kanmatsuse K. Novel mechanisms of the antiproliferative effects of amlodipine in vascular smooth muscle cells from spontaneously hypertensive rats. Hypertens Res 2002; 25:109-15. [PMID: 11924715 DOI: 10.1291/hypres.25.109] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The calcium channel blocker amlodipine continues to be of interest due to its potential proven ability to hinder the progression of atherosclerosis and reduce the number of clinical ischemic events. Vascular smooth muscle cells (VSMC) from spontaneously hypertensive rats (SHR) are useful in the study of atherosclerosis because they show exaggerated growth with production of angiotensin II (Ang II) by conversion to the synthetic phenotype. To clarify mechanisms of the antiproliferative effects of amlodipine, we evaluated effects of the expression of growth factors, the changes in phenotype, and the proliferation of VSMC from SHR. Amlodipine significantly inhibited basal DNA synthesis and proliferation of VSMC from SHR. Amlodipine also inhibited expression of platelet-derived growth factor (PDGF) A-chain, transforming growth factor beta1 (TGF-beta1) and basic fibroblast growth factor (bFGF) mRNAs in VSMC from SHR. Decreases in levels of PDGF A-chain and bFGF mRNAs in VSMC from SHR were greater with amlodipine than with nifedipine. Amlodipine significantly inhibited expression of the synthetic phenotype markers osteopontin and matrix Gla mRNAs, indicating that it inhibited the exaggerated growth of VSMC from SHR and suppressed the change from the contractile phenotype to the synthetic phenotype. Thus, amlodipine may be a beneficial therapeutic agent for patients with hypertensive vascular diseases.
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Affiliation(s)
- Yi-Mu Lai
- Second Department of Internal Medicine, Nihon University School of Medicine, Tokyo, Japan
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17
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Perfilieva E, Risedal A, Nyberg J, Johansson BB, Eriksson PS. Gender and strain influence on neurogenesis in dentate gyrus of young rats. J Cereb Blood Flow Metab 2001; 21:211-7. [PMID: 11295875 DOI: 10.1097/00004647-200103000-00004] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
To investigate whether rat hippocampal neurogenesis varies with strain and gender, the authors examined proliferating progenitor cells and their progeny in young male and female Sprague-Dawley (SD) and spontaneously hypertensive rats (SHR) using the thymidine analog bromodeoxyuridine (BrdU) combined with immunohistochemistry for the neuronal marker Calbindin D28k and glial fibrillary acidic protein. Rats were given 7 consecutive daily BrdU injections and were killed 1 day or 4 weeks later to allow for discrimination between proliferation and cell survival. Stereologic analysis of the numbers of BrdU-immunoreactive cells in the dentate gyrus revealed both a strain difference with significantly higher cell proliferation and net neurogenesis in SHR than in SD and a gender difference with males from both strains producing significantly more cells than their female counterparts. Whereas the number of progenitors four weeks after BrdU injections was still significantly greater in male than in female SHRs, resulting in a greater net neurogenesis in the male, the number of BrdU-immunoreactive cells did not differ between male and female SD rats, suggesting a greater survival of newly generated cells in the dentate gyrus in female than in male SD rats. No sex or strain difference was observed in the relative ratio of neurogenesis and gliogenesis.
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Affiliation(s)
- E Perfilieva
- Institute of Clinical Neuroscience, University of Göteborg, Sweden
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18
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Satoh C, Fukuda N, Hu WY, Nakayama M, Kishioka H, Kanmatsuse K. Role of endogenous angiotensin II in the increased expression of growth factors in vascular smooth muscle cells from spontaneously hypertensive rats. J Cardiovasc Pharmacol 2001; 37:108-18. [PMID: 11152368 DOI: 10.1097/00005344-200101000-00013] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
In culture, vascular smooth muscle cells (VSMC) derived from spontaneously hypertensive rats (SHR) show exaggerated growth compared with cells from normotensive Wistar-Kyoto (WKY) rats. SHR-derived VSMC express higher levels of transforming growth factor (TGF)-beta1, platelet-derived growth factor (PDGF) A-chain, and basic fibroblast growth factor (bFGF) mRNAs than cells from WKY rats. We have recently observed production of angiotensin II (Ang II) in homogeneous cultures of VSMC from SHR. In the current study we investigated the contribution of endogenous Ang II to increased expression of the above-mentioned growth factors in VSMC from SHR. The levels of mRNAs encoding TGF-beta1, PDGF A-chain, and bFGF were determined by reverse transcription-polymerase chain reaction and were much higher in VSMC from SHR than in cells from WKY rats. The basal level of Ang II-like immunoreactivity (LI) in conditioned medium as determined by radioimmunoassay was significantly higher in VSMC from SHR than in cells from WKY rats. Isoproterenol is known to induce angiotensinogen gene significantly increased Ang II-LI in VSMC from both WKY rats and SHR. Isoproterenol also increased angiotensinogen, TGF-beta1, PDGF A-chain, and bFGF mRNAs in VSMC from SHR. An angiotensin-converting enzyme inhibitor delapril significantly decreased Ang II-LI in VSMC from WKY rats and SHR. Delapril considerably decreased the levels of TGF-beta1, PDGF A-chain, and bFGF mRNAs in VSMC from SHR. An Ang II type 1 receptor antagonist CV 11974 decreased the levels of TGF-beta1, PDGF A-chain, and bFGF mRNAs, and the levels of TGF-beta1, PDGF-AA, and bFGF proteins in VSMC from SHR. These findings suggest that increased generation of Ang II is associated with enhanced expression of TGF-beta1, PDGF A-chain, and bFGF, and the increases in the levels of these growth factors by endogenous Ang II may contribute to the exaggerated growth of VSMC from SHR.
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MESH Headings
- Adrenergic beta-Agonists/pharmacology
- Angiotensin II/drug effects
- Angiotensin II/physiology
- Angiotensin-Converting Enzyme Inhibitors/pharmacology
- Animals
- Cells, Cultured
- Fibroblast Growth Factor 2/drug effects
- Fibroblast Growth Factor 2/metabolism
- Growth Substances/metabolism
- Male
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/metabolism
- Platelet-Derived Growth Factor/drug effects
- Platelet-Derived Growth Factor/metabolism
- RNA, Messenger/drug effects
- RNA, Messenger/metabolism
- Rats
- Rats, Inbred SHR
- Rats, Inbred WKY
- Species Specificity
- Transforming Growth Factor beta/drug effects
- Transforming Growth Factor beta/metabolism
- Transforming Growth Factor beta1
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Affiliation(s)
- C Satoh
- Second Department of Internal Medicine, Nihon University School of Medicine, Tokyo, Japan
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Kubo A, Fukuda N, Teng J, Satoh C, Nakayama M, Kishioka H, Kanmatsuse K. Angiotensin II regulates the cell cycle of vascular smooth muscle cells from SHR. Am J Hypertens 2000; 13:1117-24. [PMID: 11041167 DOI: 10.1016/s0895-7061(00)00298-3] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
We have demonstrated that spontaneously hypertensive rats (SHR)-derived vascular smooth muscle cells (VSMC) show the exaggerated growth and produce angiotensin II (Ang II). In the current study, we investigated the role of endogenous Ang II in the regulation of the cell cycle in VSMC from SHR. Levels of Ang II in conditioned medium from SHR-derived VSMC cultured without serum were significantly higher than levels in conditioned medium from Wistar-Kyoto (WKY) rat-derived VSMC. Basal DNA synthesis was higher in quiescent VSMC from SHR than that in cells from WKY rats. An Ang II type 1 receptor antagonist, CV11974, significantly inhibited the elevation in DNA synthesis in quiescent VSMC from SHR but did not affect it in cells from WKY rats. Cellular DNA content analysis by flow cytometry revealed that the proportion of cells in S phase was higher, whereas the proportion of cells in G1+G0 phase was lower in VSMC from SHR than those in cells from WKY rats. CV11974 significantly decreased the proportion of cells in S phase and correspondingly increased the proportion of cells in G1+G0 phase in VSMC from SHR, but it did not affect the proportion in cells from WKY rats. Cyclin-dependent kinase 2 (CDK2) activity, which is known to induce the progression from G1 to S phase, was higher in VSMC from SHR than in cells from WKY rats. Expression of CDK2 inhibitor p27(kip1) mRNA was markedly higher in VSMC from SHR than in cells from WKY rats. CV11974 decreased expression of p27(kip1) mRNA in VSMC from SHR, whereas CV11974 increased it in cells from WKY rats. These findings indicate that enhanced production of endogenous Ang II regulates the cell cycle especially in the progression from G1 to S phase, and increases CDK2 activity, which is independent of p27(kip1) in VSMC from SHR.
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MESH Headings
- Angiotensin II/physiology
- Angiotensin Receptor Antagonists
- Animals
- Benzimidazoles/pharmacology
- Biphenyl Compounds
- CDC2-CDC28 Kinases
- Cell Cycle/physiology
- Cell Cycle Proteins
- Cells, Cultured
- Cyclin-Dependent Kinase 2
- Cyclin-Dependent Kinase Inhibitor p27
- Cyclin-Dependent Kinases/metabolism
- DNA/biosynthesis
- Flow Cytometry
- Male
- Microtubule-Associated Proteins/genetics
- Muscle, Smooth, Vascular/cytology
- Protein Serine-Threonine Kinases/metabolism
- RNA, Messenger/antagonists & inhibitors
- RNA, Messenger/metabolism
- Rats
- Rats, Inbred SHR/metabolism
- Rats, Inbred SHR/physiology
- Rats, Inbred WKY
- Receptor, Angiotensin, Type 1
- Receptor, Angiotensin, Type 2
- Tetrazoles/pharmacology
- Tumor Suppressor Proteins
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Affiliation(s)
- A Kubo
- Second Department of Internal Medicine, Nihon University School of Medicine, Tokyo, Japan
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Hu WY, Fukuda N, Satoh C, Jian T, Kubo A, Nakayama M, Kishioka H, Kanmatsuse K. Phenotypic modulation by fibronectin enhances the angiotensin II-generating system in cultured vascular smooth muscle cells. Arterioscler Thromb Vasc Biol 2000; 20:1500-5. [PMID: 10845864 DOI: 10.1161/01.atv.20.6.1500] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
We previously demonstrated that homogeneous cultures of vascular smooth muscle cells (VSMCs) from spontaneously hypertensive rats produce angiotensin II (Ang II) in response to increases in the levels of angiotensinogen, cathepsin D, and angiotensin-converting enzyme (ACE). The change of VSMCs from the contractile to the synthetic phenotype increased the amount of synthetic organelles, resulting in the production of proteases and growth factors. To evaluate the contribution of the synthetic phenotype to the generation of Ang II, we examined the effect of fibronectin (FN), which reportedly induces the synthetic phenotype, on the Ang II-generating system in VSMCs. Cultured VSMCs from Wistar-Kyoto rats were incubated with an active fragment of FN, Arg-Gly-Asp-Ser, for 24, 48, or 72 hours after synchronization of the cell cycle with 0. 2% calf serum for 48 hours. Immunofluorescence and protein levels of alpha-smooth muscle (SM) actin and expression of SM22alpha mRNA, apparent in the contractile phenotype, were suppressed by FN, whereas expression of matrix Gla mRNA and osteopontin mRNA and protein, apparent in the synthetic phenotype, was increased. FN (1 to 1000 microg/mL) dose-dependently increased DNA synthesis in the VSMCs, which was inhibited by the Ang II type 1 receptor antagonist CV-11974. Ang II-like immunoreactivity as determined by radioimmunoassay was significantly increased in conditioned medium from the VSMCs. In addition, mRNA for the Ang II-generating proteases cathepsin D and ACE was increased by FN. Expression of transforming growth factor-beta1, platelet-derived growth factor A-chain, and basic fibroblast growth factor mRNAs was also increased by FN. These results indicate that the changes accompanying the alteration to the synthetic phenotype in homogeneous cultures of VSMCs increase expression of proteases such as cathepsin D and ACE, which then produce Ang II, and that these changes increase expression of growth factors that then induce growth of VSMCs.
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Affiliation(s)
- W Y Hu
- Second Department of Internal Medicine, Nihon University School of Medicine, Tokyo, Japan
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21
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Fukuda N, Hu WY, Satoh C, Nakayama M, Kishioka H, Kubo A, Kanmatsuse K. Contribution of synthetic phenotype on the enhanced angiotensin II-generating system in vascular smooth muscle cells from spontaneously hypertensive rats. J Hypertens 1999; 17:1099-107. [PMID: 10466465 DOI: 10.1097/00004872-199917080-00009] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE We have demonstrated that cultured vascular smooth muscle cells (VSMC) from spontaneously hypertensive rats (SHR), but not from normotensive Wistar-Kyoto (WKY) rats, produce angiotensin II (Ang II) in a homogeneous culture with increased levels of angiotensinogen, cathepsin D and angiotensin converting enzyme (ACE) at early passages. In the current study, we investigated how changes in the cell phenotype affect the Ang II-generating system and the growth of VSMC from SHR. DESIGN AND METHODS We evaluated basal DNA synthesis by [3H]thymidine incorporation, immunofluorescence of alpha-smooth muscle (SM) actin, mRNA expression of phenotype markers such as SM22alpha appeared by contractile phenotype, Ang II-generating system components and growth factors by reverse transcription and polymerase chain reaction analysis, and Ang II levels by radioimmunoassay in quiescent VSMC from WKY/Izumo rats and SHR/Izumo at passages 4, 8 and 12. RESULTS Basal DNA synthesis in VSMC from WKY rats increased with increasing passage number, whereas in cells from SHR it was markedly higher at early passages and was not affected by the passages. At early passage numbers, immunofluorescence of alpha-SM actin was stronger in VSMC from WKY rats than in cells from SHR, but decreased after several passages. Expression of SM22alpha mRNA was higher in VSMC from WKY rats than in cells from SHR at early passages, and decreased after several passages in cells from both rat strains. Expression of matrix Gla mRNA was higher in VSMC from SHR than in cells from WKY rats at early passage, and increased after several passages in cells from both rat strains. Ang II was not detected at early passages but increased in VSMC from WKY rats with increasing passage, whereas it was detected in VSMC from SHR at early passages and did not change with the passages. Expression of angiotensinogen mRNA was higher in VSMC from SHR than in cells from WKY rats, and was not affected by the passages. Expressions of cathepsin D and ACE mRNA were higher in VSMC from SHR than in cells from WKY rats at early passage, and were increased by the passages in VSMC from WKY rats. Expressions of transforming growth factor-beta1, platelet-derived growth factor A-chain, and basic fibroblast growth factor mRNA were significantly higher in VSMC from SHR than in cells from WKY rats, and were increased by the passages. CONCLUSION These data indicate that early in culture VSMC from SHR have the synthetic phenotype, whereas VSMC from WKY rats have the contractile phenotype which then changes to the synthetic phenotype after increased passage numbers, with increased expression of cathepsin D and ACE, which produce Ang II, and increased expression of Ang II-related growth factors, which induce the exaggerated growth observed in VSMC from SHR.
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Affiliation(s)
- N Fukuda
- Second Department of Internal Medicine, Nihon University School of Medicine, Tokyo, Japan
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