エラスターゼ活性阻害による心筋保護と心血管前駆細胞の分化誘導

金沢大学医薬保健研究域医学系心筋梗塞後の心拡大や心機能低下の程度は虚血障害の強度とそれに引き続く心筋リモデリングに依存し,特に蛋白分解活性による細胞外基質の変化が重要である。本研究では、エラスターゼ阻害因子の一つelafinの過剰発現マウス(本マウス)を用いて、エラスターゼ活性阻害による心筋保護作用について検討を行った。本マウスでの冠動脈結紮による心筋梗塞病変は、14日後野生マウス(対照)に比べて有意に抑制されることが示された(p<0.03)。これは冠動脈結紮後に対照で観察されるエラスターゼの完全な抑制と、ミエロペルオキシダーゼ、MMP2の活性抑制と関連していた。また本マウスにおける冠動脈結紮28日後の心筋収縮力は有意に維持されていた(p<0.03)。さらに、梗塞部位に前駆細胞と考えられるCD34陽性細胞が対照にくらべて集積している傾向があった。つまり、エラスターゼ阻害因子により構築を保たれた部位では、骨髄や末梢から誘導された前駆細胞を効率良く取り込み、心血管系細胞に分化誘導させ、対照では変性した細胞外基質がこれらをコラーゲン線維産生細胞と考えられる線維芽細胞に分化せしめ、心筋リモデリングを修飾し、晩期における心構築、心機能の差となる可能性が示唆された。この仮説を検証するため、X-Galを構成的に発現するROSA26マウスの骨髄を同系野生マウスに移植し、骨髄再構成後に心筋梗塞モデルを作成した。このモデルで、骨髄由来細胞の梗塞部位への集積と分化が観察されており、エラスターゼ阻害剤を投与することで現在エラスターゼの関与を検討している。一方、種々の細胞外基質を塗布した培養皿でマウス骨髄由来接着細胞を培養すると、様々な分化パターンを示すことが観察され、心血管前駆細胞の分化誘導における細胞外基質の重要性が示唆された。研究課題/領域番号:14770349, 研究期間(年度):2002-2003出典：「エラスターゼ活性阻害による心筋保護と心血管前駆細胞の分化誘導」研究成果報告書　課題番号14770349（KAKEN：科学研究費助成事業データベース（国立情報学研究所））（https://kaken.nii.ac.jp/ja/grant/KAKENHI-PROJECT-14770349/)を加工して作

ヒト末梢血,リンパ組織におけるBc1-2関連蛋白,Bc1-2,Bax,Bc1-X,Mc1-1の発現のイムノブロット法による解析

取得学位 : 博士（医学）, 学位授与番号 : 医博甲第1198号, 学位授与年月日：平成8年3月25日,学位授与年：199

Natural history of medium-sized atrial septal defect in pediatric cases

AbstractBackgroundThe indication for surgical repair of atrial septal defect (ASD) is pulmonary to systemic blood flow ratio (Qp/Qs)>2.0, and therapeutic strategy depends on the facility in cases of Qp/Qs 1.5–2.0. Defect size increases with age, but hemodynamic changes of medium-sized ASD (Qp/Qs 1.5–2.0) are unknown.Methods and resultsFrom April 1, 1985 to March 31, 2008, we experienced 125 cases of cardiac catheterization for ASD. Twelve cases were re-evaluated without surgical repair. The first and second catheterizations were performed at median ages of 7 years (range, 2–13 years) and 16 years (range, 5–19 years), respectively. The mean follow-up period was 7 years. Qp/Qs increased from 1.6 to 2.0 during follow-up (p<0.05). Of four cases with Qp/Qs<1.5 at initial presentation, three had Qp/Qs≥1.5 at second inspection. Right ventricle diastolic volume (RVEDV/LVEDV) also increased.ConclusionsQp/Qs and RVEDV/LVEDV of medium-sized ASD increase together in childhood. Re-evaluation before adulthood should be considered in patients with no indications of ASD closure in childhood

Bacterial nucleoid dynamics: oxidative stress response in Staphylococcus aureus

A single-molecule-imaging technique, atomic force microscopy (AFM) was applied to the analyses of the genome architecture of Staphylococcus aureus. The staphylococcal cells on a cover glass were subjected to a mild lysis procedure that had maintained the fundamental structural units in Escherichia coli. The nucleoids were found to consist of fibrous structures with diameters of 80 and 40 nm. This feature was shared with the E. coli nucleoid. However, whereas the E. coli nucleoid dynamically changed its structure to a highly compacted one towards the stationary phase, the S. aureus nucleoid never underwent such a tight compaction under a normal growth condition. Bioinformatic analysis suggested that this was attributable to the lack of IHF that regulate the expression of a nucleoid protein, Dps, required for nucleoid compaction in E. coli. On the other hand, under oxidative conditions, MrgA (a staphylococcal Dps homolog) was over-expressed and a drastic compaction of the nucleoid was detected. A knock-out mutant of the gene encoding the transcription factor (perR) constitutively expressed mrgA, and its nucleoid was compacted without the oxidative stresses. The regulatory mechanisms of Dps/MrgA expression and their biological significance were postulated in relation to the nucleoid compaction

Phosphodiesterase Inhibitors Suppress Lactobacillus casei Cell-Wall-Induced NF-κB and MAPK Activations and Cell Proliferation through Protein Kinase A—or Exchange Protein Activated by cAMP-Dependent Signal Pathway

Specific strains of Lactobacillus have been found to be beneficial in treating some types of diarrhea and vaginosis. However, a high mortality rate results from underlying immunosuppressive conditions in patients with Lactobacillus casei bacteremia. Cyclic AMP (cAMP) is a small second messenger molecule that mediates signal transduction. The onset and progression of inflammatory responses are sensitive to changes in steady-state cAMP levels. L. casei cell wall extract (LCWE) develops arteritis in mice through Toll-like receptor-2 signaling. The purpose of this study was to investigate whether intracellular cAMP affects LCWE-induced pathological signaling. LCWE was shown to induce phosphorylation of the nuclear factor κB (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways and cell proliferation in mice fibroblast cells. Theophylline and phosphodiesterase inhibitor increased intracellular cAMP and inhibited LCWE-induced cell proliferation as well as phosphorylation of NF-κB and MAPK. Protein kinase A inhibitor H89 prevented cAMP-induced MAPK inhibition, but not cAMP-induced NF-κB inhibition. An exchange protein activated by cAMP (Epac) agonist inhibited NF-κB activation but not MAPK activation. These results indicate that an increase in intracellular cAMP prevents LCWE induction of pathological signaling pathways dependent on PKA and Epac signaling

Lactobacillus casei cell wall extract directly stimulates the expression of COX2 independent of Toll-like receptor 2 in rat glial cells

Kawasaki disease is an acute illness of early childhood that is characterized by prolonged fever and vasculitis of unknown pathogenesis. Lactobacillus casei cell wall extract (LCWE)-induced vasculitis in mice is a well-validated model of Kawasaki disease. In the nervous system, glial cells play an important role in fever development. This study investigated whether LCWE directly stimulates glial cells, resulting in the induction of cyclooxygenase-2 (COX2), which is required for prostaglandin synthesis and fever development. We found that LCWE induced COX2 expression and activated the nuclear factor-κB signaling pathway in rat B92 glial cells, but Toll-like receptor-2, which is one of the receptors for LCWE, could not be detected in the cells. These results suggest that LCWE activates the nuclear factor-κB signaling pathway and induces COX2 in rat B92 glial cells through another LCWE receptor other than Toll-like receptor-2. © 2012

Tumor necrosis factor-α modifies the effects of Shiga toxin on glial cells

Shiga toxin (STX) is one of the main factors inducing hemorrhagic colitis and hemolytic-uremic syndrome (HUS) in infections with STX-producing Escherichia coli (STEC). Approximately 62% of patients with HUS showed symptoms of encephalopathy in the 2011 Japanese outbreak of STEC infections. At that time, we reported elevated serum concentrations of tumor necrosis factor (TNF)-α in patients with acute encephalopathy during the HUS phase. In the current study, we investigated whether TNF-α augments the effects of STX in glial cell lines and primary glial cells. We found that TNF-α alone or STX in combination with TNF-α activates nuclear factor-κB (NF-κB) signaling and inhibits growth of glial cells. The magnitude of the NF-κB activation and the inhibition of cell growth by the STX and TNF-α combination was greater than that obtained with TNF-α alone or STX alone. Thus, this in vitro study reveals the role of TNF-α in glial cells during STEC infections. © 2016 Elsevier B.V. All rights reserved.Embargo Period 12 month

Successful Treatment with Bosentan for Pulmonary Hypertension and Reduced Peripheral Circulation in Juvenile Systemic Sclerosis

Pulmonary arterial hypertension (PAH) when associated with systemic sclerosis (SSc) (SSc-PAH) is one of the leading causes of mortality and is found in 10-15% of adult patients with SSc. The ET receptor antagonist bosentan has been shown to be effective in the treatment of adult patients with SSc-PAH. Furthermore, it has been shown that bosentan ameliorates decreased skin perfusion and digital ulceration secondary to SSc. However, the effectiveness and safety of bosentan for treatment of juvenile SSc still remains unclear. We describe a case of juvenile SSc-PAH successfully treated with bosentan. The present case shows that bosentan ameliorated PAH and peripheral circulation as evaluated by cold stress thermography. No bosentan-related adverse events such as liver dysfunction were observed. Prospective randomized trials are required to validate the effectiveness of bosentan for patients with juvenile SSc; however, bosentan might be useful for the management of patients with juvenile SSc. © 2011 Springer Science+Business Media, LLC