Biomedical subjects

Satoru Kitagawa-Sakakida

Publications and source records attributed to Satoru Kitagawa-Sakakida.

6 recordsLinked to original sources

PubMed2005

Microarray-based gene expression profiling of retransplanted rat cardiac allografts that develop cardiac allograft vasculopathy.

We studied the expression of 9,906 genes in retransplanted rat cardiac allografts that developed cardiac allograft vasculopathy (CAV) with the use of DNA microarray and real-time reverse transcriptase-polymerase chain reaction. Although only a slight difference in the timing of the retransplantation induced the later development of CAV, 1,067 genes were differentially expressed in the allografts 1 day after retransplantation. Thus, the development of CAV was determined by a robust difference in gene expression soon after retransplantation, controlled by a slight difference in retransplantation timing. In contrast, only 26 genes showed significant upregulation in the later phase of CAV development, and the time-course of the induction of 16 genes was associated with CAV progression. Of these genes, 8 were induced in 2 different aortic allograft combinations, and the time-course of the induction was correlated with the development of transplant vasculopathy. Microarray-based gene expression profiling has the potential to elucidate the mechanism of experimental chronic cardiac allograft rejection.

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PubMed2005

Reorganization of cytoskeletal proteins and prolonged life expectancy caused by hepatocyte growth factor in a hamster model of late-phase dilated cardiomyopathy.

OBJECTIVE: It has been postulated recently that changes in cytoskeletal and sarcolemmal proteins initiate a final common pathway for contractile dysfunction in dilated cardiomyopathy. In ischemic cardiomyopathy, hepatocyte growth factor plays an important role in reorganizing the impaired cytoskeletal proteins in several cell types. We have tested the hypothesis that hepatocyte growth factor might improve life expectancy through modification of the molecular process that contributes to impairment in dilated cardiomyopathy. METHODS: Adult male 27-week-old BIO TO-2 hamsters, which show moderate cardiac remodeling, were divided into treatment groups that received (1) hemagglutinating virus of Japan liposomes containing human hepatocyte growth factor cDNA (H group), (2) culture medium (C group), or (3) sham operation (S group). RESULTS: After the operation, echocardiography demonstrated that the enlarged left ventricular end-systolic dimension and decreased fractional shortening were significantly attenuated in the H group compared with the C group. There was significantly less myocardial fibrosis in the H group compared with the C group. Immunohistochemical analysis showed alpha-dystroglycan and alpha- and beta-sarcoglycan expression in the basement membrane beneath the cardiomyocytes in the H group, whereas no expression of these proteins was seen in the C group. The 40-week survival was significantly better in the H group than in the C and S groups. CONCLUSION: An improved survival associated with transient reorganization of the cytoskeletal proteins and reduction in myocardial fibrosis was achieved by hepatocyte growth factor treatment in an adult hamster model of dilated cardiomyopathy. The results suggest a therapeutic potential of hepatocyte growth factor in the treatment of dilated cardiomyopathy.

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PubMed2005

Gene transfection of hepatocyte growth factor attenuates the progression of cardiac remodeling in the hypertrophied heart.

OBJECTIVES: Hepatocyte growth factor plays a significant role in angiogenesis, anti-apoptosis, and anti-transforming growth factor-beta1-mediated fibrosis in several organs. In this study, we investigated the effect of transfection of the hepatocyte growth factor gene in attenuation of cardiac remodeling in the hypertrophied heart. METHODS: Two weeks after banding the ascending aorta of male Sprague-Dawley rats, a hemagglutinating virus of Japan-liposome complex with (H group) or without (C group) human hepatocyte growth factor cDNA was transfected into the left ventricle wall by direct injection. The hepatocyte growth factor, c-Met, and transforming growth factor-beta1 mRNA levels in the left ventricle were then analyzed by real-time quantitative reverse-transcriptase polymerase chain reaction. RESULTS: Two weeks after transfection, the expression of transforming growth factor-beta1 mRNA was significantly attenuated in the H group compared with the C group (P < .01). Myocardial collagen content after 4 weeks of banding was significantly lower in the H group (5.0 +/- 0.6 mg/g tissue) than in the C group (7.4 +/- 0.5 mg/g tissue, P < .01). Left ventricular diastolic function (E/A ratios quantified by Doppler echocardiography) showed a significant increase in the H group (1.9 +/- 0.1) compared with the C group (1.1 +/- 0.1, P < .01). CONCLUSIONS: Our results demonstrated that gene transfection of hepatocyte growth factor attenuated left ventricular diastolic dysfunction and cardiac fibrosis in association with a decrease in transforming growth factor-beta1 in the rat heart subjected to pressure overload. Thus, the transfection of the hepatocyte growth factor gene into the hypertrophied heart may be a strategy for the hypertrophied and failing heart even for cardiac surgery.

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PubMed2005

150-kDa oxygen-regulated protein attenuates myocardial ischemia-reperfusion injury in rat heart.

Early contractile dysfunction and the later death of cardiomyocytes are two major problems that can follow myocardial infarction or major cardiovascular surgery that demands ischemic arrest of the heart. Here, we found that 24 h of hypoxia and 1 h of reoxygenation induced the expression of the chaperone ORP150 in cultured rat cardiomyocytes. Inhibition of its induction using an adenovirus to express anti-sense ORP150 significantly enhanced the hypoxia-reoxygenation-induced cardiomyocyte death; cell death was reduced by overexpressing ORP150. Decreased levels of ORP150 expression also enhanced caspase-3 and -8 activation, cytochrome-c release, and DNA fragmentation, suggesting that this chaperone regulates apoptotic cell death. In contrast, increasing the expression of ORP150 in the cardiomyocytes had the opposite effect on the expression of these molecules. Moreover, apoptotic cell death initiated by myocardial ischemia-reperfusion (I/R) was significantly inhibited in vivo by transfecting an ORP150 expression plasmid into whole rat heart using the hemagglutinating virus of Japan (HVJ)-liposome method. Interestingly, ORP150 seemed to preserve calcium homeostasis in cardiomyocytes that underwent ischemia-reoxygenation in vitro. Calpain activity in the cardiomyocytes was enhanced by anti-sense ORP150 and suppressed by sense ORP150. Finally, we examined the functional recovery of rat hearts that overexpressed ORP150 or GFP protein and were subjected to I/R; we found that ORP150 preserved early contractile function after transient ischemia. Our results indicated cytoprotective roles for ORP150 in rat heart and suggested a therapeutic role for the protein both in preventing cardiomyocyte death and in preserving contractile function after ischemic damage.

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PubMed2003

Antibody deposition in rat heart which develops transplant vasculopathy in (donor x recipient) F1 environment.

PURPOSE: We studied the gene expression in rat cardiac allografts retransplanted into (donor x recipient) F1 animals to identify unknown or unexpected genes whose expression might contribute to the progression of transplant vasculopathy. METHODS: Gene expression was first studied using a mRNA differential display, then it was further investigated using quantitative reverse transcription-polymerase chain reaction and immunohistochemistry. RESULTS: We found that the rat immunoglobulin kappa chain gene was preferentially induced in retransplanted cardiac allografts in which transplant vasculopathy was developing. The diseased vessels in the same allografts were heavily infiltrated with CD45R-positive B cells. The expression of two genes related to B-cell responses, B-lymphocyte chemoattractant, and CD40 ligand, showed a similar time course to that of the immunoglobulin kappa chain gene. We observed a heavy deposit of both IgM and IgG on the pathological neointima late in the development of transplant vasculopathy (i.e., 30 days after retransplantation) that was absent from the allografts immediately after retransplantation. CONCLUSION: During the development of transplant vasculopathy in a (donor x recipient) F1 environment, B cells were selectively recruited into the allografts and stimulated; meanwhile, antibodies against the pathological neointima were formed. These antibodies may be involved in the pathogenesis of transplant vasculopathy.

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PubMed2002

Selective chemokine and receptor gene expressions in allografts that develop transplant vasculopathy.

BACKGROUND: Chemokine systems probably play a role in transplant vasculopathy; however, a comprehensive study of the expression of chemokines and their receptors in this disease has not been performed. METHODS: The expression of all the rat chemokines and chemokine receptor genes for which the nucleotide sequences are known were quantitatively monitored using the fluorescence-based real-time reverse-transcriptase polymerase chain reaction technique, and selected cytokine-receptor pairs were determined using immunohistochemical staining. The analysis covered the whole time course of transplant vasculopathy in 2 different graft models (cardiac and aortic grafts) with 4 different strain combinations of rats. RESULTS: Among the 13 receptor genes examined, the CXCR3, CCR5, and CCR2 genes and those of their corresponding ligands were selectively and strongly induced in grafts that develop transplant vasculopathy. The expression patterns of the receptors were similar in both cardiac and aortic allografts, although their induction and their absolute levels of expression were amplified several fold in the grafted aorta compared with heart grafts. The genes were induced before morphologic changes became apparent and expression was sustained during the whole period of neointimal formation. Interestingly, immunohistochemical staining for CXCR3 showed a unique pattern of expression: we found weak expression on cells in the outer layer of the neointima and adventitia and found the strongest staining in the innermost layer of the neointima. CONCLUSIONS: This study suggested diagnostic as well as potential functional roles of the chemokine-receptor pairs IP10-CXCR3, RANTES-CCR5, and MCP1-CCR2 in rat models of transplant vasculopathy.

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