1998 Fiscal Year Annual Research Report

新しいホメオボックス遺伝子Gaxの血管平滑筋分化誘導の分子機構とその臨床的意義

Research Project

Project/Area Number	10177216
Research Institution	Kyoto University
Principal Investigator	伊藤裕京都大学, 医学研究科, 助手 (40252457)
Keywords	血管平滑筋 / cGMP / ナトリウム利尿ペプチド / ホメオボックス / キナーゼ / 増殖 / トランスジェニックマウス
Research Abstract	近年同定されたGax(Growth arrest-specific homeobox)は、大動脈、心臓など循環器系特異的発現を示すホメオボックス遺伝子であり、血清やPDGF等の増殖促進因子によって発現が抑制されること、その過剰発現により血管平滑筋細胞(VSMC)増殖が阻害されることが示され、VSMCの増殖抑制において重要な意義を有すると考えられている。これまでに我々は、血管作動性ペプチドであるアンギオテンシンII(AII)とナトリウム利尿ペプチドがVSMCの増殖に対し拮抗的に作用していること、Gaxの発現がAII及びC型ナトリウム利尿ペプチドによりそれぞれ抑制及び促進されることを明らかにし、GaxがVSMC増殖抑制シグナルにおいて、共通の転写因子として関与する可能性を示した。本年度は以下の結果を得た。 (1) cGMPc/cGMP依存性プロテインキナーゼ(cGK)/Gax経路の同定とその発現調節:我々が既にクローニングしたヒトcGKIα全長cDNAより、N端側の二量化ドメイン・cGMP結合ドメインを欠失させ、ほぼ媒介ドメインのみからなる持続活性型cGKIα(335-671a.a.)を構築した。得られた持続活性型cGK発現ベクターをVSMCに導入したところ、l%血清刺激下において対照群に比べ約2倍のGax発現の亢進を認めた。更に、内因性Gax発現の欠失する培養ラット胎児由来血管平滑筋細胞株A7r5を用い、持続活性型cGK及びGax発現permanent cell lineを樹立し細胞増殖を検討したところ、cGK及びGax発現細胞において、ともにサイクリン依存性キナーゼ阻害因子p21^<cipl>発現の亢進に伴い、紡錘形への細胞形態の変化及び増殖速度の著明な低下を認めた。更に、cGMP経路によるVSMC増殖抑制において実際にGaxが関与しているかについて、アンチセンスDNA法により検討した。その結果、Gax mRNAに特異的なアンチセンスオリゴヌクレオチド10^<-6>Mの導入により血管平滑筋細胞でのGax発現は約70%抑制され、この時cGMPによるp21^<cipl>発現の亢進及び増殖抑制はほぼ完全に阻害された。この結果は、cGMP/cGKによる血管平滑筋細胞増殖抑制においてGaxが必須であることを示している。 (2) cGKトランスジェニックマウスの開発:我々がクローニングしたcGKcDNAを3コピー及び15コピー有するトランスジェニックマウス(cGK.Tg)を開発した。このcGK.Tgでは、心臓、肺、血管、骨格筋、小脳においてcGK活性の亢進を認めた。

Research Products

(19 results)

All Other

All Publications (19 results)

[Publications] K.Masatsugu et al.: "Physiologic shear stress suppresses endothelin-converting enzyme-1 expression in vascular endothelial cells." J.Cardiovasc.Pharmacol.31 SUPPL 1. S42-S45 (1998)
[Publications] T.Saito et al.: "Oxidative stress suppresses the endothelial secretion of endothelin." J.Cardiovasc.Pharmacol.31 SUPPL 1. S45-S47 (1998)
[Publications] T.Igaki et al.: "Effects of intravenously administered C-type natriuretic peptide in humans--Comparison with atrial natriuretic peptide." Hypertens.Res.21. 7-13 (1998)
[Publications] S.Suga et al.: "Regulation of endothelial production of C-type natriuretic peptide by interaction between endothelial cells and macrophages." Endocrinology. 139. 1920-1926 (1998)
[Publications] M.Suda et al.: "Skeletal overgrowth in transgenic mice that overexpress brain natriuretic peptide." Proc.Natl.Acad.Sci.U.S.A.95. 2337-2342 (1998)
[Publications] N.Azuma et al.: "The significance of the Trp 64 Arg mutation of the b3-adrenergic receptor gene in impaired glucose tolerance, non-insulin-dependent diabetes mellitus, and insulin resistance in Japanese subjects." Metabolism. 47. 456-460 (1998)
[Publications] M.Inoue et al.: "Vascular endothelial growth factor(VEGF)expression in human coronary atherosclerotic lesions:Possible pathophysiological significance of VEGF in progression of atherosclerosis." Circulation. 98. 2108-2116 (1998)
[Publications] Y.Miyamoto et al.: "Endothelial nitric oxide synthase gene is positively associated with essintial hypertension." Hypertension. 32. 3-8 (1998)
[Publications] J.Matsuda et al.: "increased adipose expression of uncoupling protein-3 gnene by thiazolidinediones in Wistar fatty rats and in cultured adipocytes." Diabetes. 47. 1809-1814 (1998)
[Publications] M.Yamaguchi et al.: "Effect of neutral endopeptidase inhibition on the natriuresis and renal clearance of atrial natriuretic peptide in perfused rat kidney." Pharmaceutical Research. 15. 1499-1502 (1998)
[Publications] K.Doyama et al.: "Expression and distribution of brain natriuretic peptide in human right atria." J.Am.Coll.Cardiol.32. 1832-1838 (1998)
[Publications] H.Itoh et al.: "Hypertension and insulin resistance-The role of peroxisome proliferator-activated receptor-γ(PPARγ)-" Clinical and Experimental Pharmacology and Physiology. (in press). (1999)
[Publications] Y.Numata et al.: "Immunoradiometric assay for the N-terminal fragment of proatrial natriuretic peptide in human plasma." Clinical Chemistry. 44. 1008-1013 (1998)
[Publications] M.Harada et al.: "Interaction of myocytes and nonmyocytes is necessary for mechanical stretch to induce ANP/BNP production in cardiocyte culture." J.Cardiovasc.Pharmacol.31 SUPPL 1. S357-S359 (1998)
[Publications] G.Takemura et al.: "Expression of atrial and brain natriuretic peptides and their genes in hearts of patients with cardiac amyloidosis." J.Am.Coll.Cardiol.31. 254-265 (1998)
[Publications] J.Yamashita et al.: "Identification of cis-element of the human endothelin-A receptor gene and inhibition of the gene expression by the decoy strategy." J.Biol.Chem.273. 15993-15999 (1998)
[Publications] H.Nanno et al.: "Plasma nitric oxide metabolite levels are decreased in pre-eclamptic woman complicated with fetal distress." Prenat.Neonat Med.3. 222-226 (1998)
[Publications] H.Nanno et al.: "Nitric oxide metabolite concentrations in maternal plasma decrease during parturition: possible transient down-regulation of nitric oxide synthesis." Molecular Human Reproduction. 4. 609-616 (1998)
[Publications] T.Tanaka et al.: "Down-regulation of peroxisome proliferator-activated receptorg expression by inflammatory cytokines and its reversal by thiazolidinediones." Diabetologia. (in press). (1999)

1998 Fiscal Year Annual Research Report

新しいホメオボックス遺伝子Gaxの血管平滑筋分化誘導の分子機構とその臨床的意義

Principal Investigator

伊藤 裕 京都大学, 医学研究科, 助手 (40252457)

Research Products

[Publications] K.Masatsugu et al.: "Physiologic shear stress suppresses endothelin-converting enzyme-1 expression in vascular endothelial cells." J.Cardiovasc.Pharmacol.31 SUPPL 1. S42-S45 (1998)

[Publications] T.Saito et al.: "Oxidative stress suppresses the endothelial secretion of endothelin." J.Cardiovasc.Pharmacol.31 SUPPL 1. S45-S47 (1998)

[Publications] T.Igaki et al.: "Effects of intravenously administered C-type natriuretic peptide in humans--Comparison with atrial natriuretic peptide." Hypertens.Res.21. 7-13 (1998)

[Publications] S.Suga et al.: "Regulation of endothelial production of C-type natriuretic peptide by interaction between endothelial cells and macrophages." Endocrinology. 139. 1920-1926 (1998)

[Publications] M.Suda et al.: "Skeletal overgrowth in transgenic mice that overexpress brain natriuretic peptide." Proc.Natl.Acad.Sci.U.S.A.95. 2337-2342 (1998)

[Publications] N.Azuma et al.: "The significance of the Trp 64 Arg mutation of the b3-adrenergic receptor gene in impaired glucose tolerance, non-insulin-dependent diabetes mellitus, and insulin resistance in Japanese subjects." Metabolism. 47. 456-460 (1998)

[Publications] M.Inoue et al.: "Vascular endothelial growth factor(VEGF)expression in human coronary atherosclerotic lesions:Possible pathophysiological significance of VEGF in progression of atherosclerosis." Circulation. 98. 2108-2116 (1998)

[Publications] Y.Miyamoto et al.: "Endothelial nitric oxide synthase gene is positively associated with essintial hypertension." Hypertension. 32. 3-8 (1998)

[Publications] J.Matsuda et al.: "increased adipose expression of uncoupling protein-3 gnene by thiazolidinediones in Wistar fatty rats and in cultured adipocytes." Diabetes. 47. 1809-1814 (1998)

[Publications] M.Yamaguchi et al.: "Effect of neutral endopeptidase inhibition on the natriuresis and renal clearance of atrial natriuretic peptide in perfused rat kidney." Pharmaceutical Research. 15. 1499-1502 (1998)

[Publications] K.Doyama et al.: "Expression and distribution of brain natriuretic peptide in human right atria." J.Am.Coll.Cardiol.32. 1832-1838 (1998)

[Publications] H.Itoh et al.: "Hypertension and insulin resistance-The role of peroxisome proliferator-activated receptor-γ(PPARγ)-" Clinical and Experimental Pharmacology and Physiology. (in press). (1999)

[Publications] Y.Numata et al.: "Immunoradiometric assay for the N-terminal fragment of proatrial natriuretic peptide in human plasma." Clinical Chemistry. 44. 1008-1013 (1998)

[Publications] M.Harada et al.: "Interaction of myocytes and nonmyocytes is necessary for mechanical stretch to induce ANP/BNP production in cardiocyte culture." J.Cardiovasc.Pharmacol.31 SUPPL 1. S357-S359 (1998)

[Publications] G.Takemura et al.: "Expression of atrial and brain natriuretic peptides and their genes in hearts of patients with cardiac amyloidosis." J.Am.Coll.Cardiol.31. 254-265 (1998)

[Publications] J.Yamashita et al.: "Identification of cis-element of the human endothelin-A receptor gene and inhibition of the gene expression by the decoy strategy." J.Biol.Chem.273. 15993-15999 (1998)

[Publications] H.Nanno et al.: "Plasma nitric oxide metabolite levels are decreased in pre-eclamptic woman complicated with fetal distress." Prenat.Neonat Med.3. 222-226 (1998)

[Publications] H.Nanno et al.: "Nitric oxide metabolite concentrations in maternal plasma decrease during parturition: possible transient down-regulation of nitric oxide synthesis." Molecular Human Reproduction. 4. 609-616 (1998)

[Publications] T.Tanaka et al.: "Down-regulation of peroxisome proliferator-activated receptorg expression by inflammatory cytokines and its reversal by thiazolidinediones." Diabetologia. (in press). (1999)

伊藤裕京都大学, 医学研究科, 助手 (40252457)