PubMed Health⌕ Search

Biomedical subjects

Ryuichi Morishita

Publications and source records attributed to Ryuichi Morishita.

At least 19 recordsLinked to original sources

Quantitative measurement of neurological deficit after mild (30 min) transient middle cerebral artery occlusion in rats.

Although 30-min transient middle cerebral artery occlusion (30-min tMCAo) causes reproducible subcortical infarction in rats, it is difficult to evaluate the resulting neurological deficit using common behavioral tests such as the rota-rod test, adhesive-removal test, or narrow beam test. Establishment of a method of quantitative evaluation would help to develop a novel therapeutic approach to treat cerebral infarction. To solve this problem, we examined whether the neurological deficit could be detected by the Montoya staircase test or methamphetamine-induced rotation, which are commonly used in a Parkinson disease model induced by intrastriatal injection of 6-hydroxydopamine (6-OHDA). From 10 to 14 days after tMCAo, the Montoya staircase test showed significant clumsiness in forelimb tasks contralateral to the lesion side, whereas sham-operated rats showed no significant clumsiness in both forelimbs. The number of ipsilateral rotations induced by methamphetamine was also increased in tMCAo-rats at 21 days after tMCAo. Although Pearson's correlations coefficient showed that the results of these tests were correlated with the infarction volume, there was no significant correlation between the results of these two tests. These findings imply that the neurological deficit detected by both tests might reflect the severity of ischemic injury, but each test might evaluate different aspects of neurological deficit. Thus, the Montoya staircase test and methamphetamine-induced rotation are useful to evaluate neurological deficit in the chronic stage of subcortical infarction induced by 30-min tMCAo.

Animals↗

Stent-based local delivery of nuclear factor-kappaB decoy attenuates in-stent restenosis in hypercholesterolemic rabbits.

BACKGROUND: Nuclear factor-kappaB (NF-kappaB) plays a critical role in the vascular response to injury. However, the role of NF-kappaB in the mechanism of in-stent restenosis remains unclear. We therefore tested the hypothesis that blockade of NF-kappaB by stent-based delivery of a cis-element "decoy" of NF-kappaB reduces in-stent neointimal formation. METHODS AND RESULTS: Stents were coated with a polymer containing or not containing NF-kappaB decoy, which represented a fast-release formulation (<7 days). Bare, polymer-coated, and NF-kappaB decoy-eluting stents were implanted in iliac arteries of hypercholesterolemic rabbits. Increased NF-kappaB activity was noted at early stages after stenting, which was suppressed by stent-based delivery of NF-kappaB decoy. NF-kappaB decoy-eluting stents also reduced monocyte infiltration and monocyte chemoattractant protein-1 expression and suppressed CD14 activation on circulating leukocytes. Importantly, NF-kappaB decoy-eluting stents attenuated neointimal formation on day 28. There was no evidence of an incomplete healing process (persistent inflammation, hemorrhage, fibrin deposition, impaired endothelial regeneration) at the site of NF-kappaB decoy-eluting stents. Transfection of NF-kappaB decoy suppressed proliferation of human coronary artery smooth muscle cells in vitro. No systemic adverse effects of NF-kappaB decoy were detected. CONCLUSIONS: Stent-based local delivery of NF-kappaB decoy reduced in-stent neointimal formation with no evidence of incomplete healing. These data suggest that this strategy may be a practical and promising means for prevention of in-stent restenosis in humans.

Angioplasty, Balloon, Coronary↗

Transfection of human hepatocyte growth factor gene ameliorates secondary lymphedema via promotion of lymphangiogenesis.

BACKGROUND: Lymphedema is a disorder of the lymphatic vascular system characterized by impaired lymphatic return and swelling of the extremities. Treatment for this disabling condition remains limited and largely ineffective. The goal of the present study was to investigate the therapeutic efficacy of hepatocyte growth factor (HGF) in animal models of lymphedema. METHODS AND RESULTS: Immunofluorescent analysis demonstrated that canine primary lymphatic endothelial cells (cLECs) were positive for lymphatic-specific markers (vascular endothelial growth factor receptor-3, LYVE-1, podoplanin, and Prox1) and the HGF receptor c-Met. Treating cLECs with human recombinant HGF resulted in a dose-dependent increase in cell growth and migration and increased activity of extracellular signal-regulated kinase and Akt. In human LECs, c-Met also was expressed, and treatment with HGF increased cell growth and migration in a dose-dependent manner. Transfection of human HGF plasmid DNA in cLECs also increased the c-fos promoter activity. Furthermore, weekly HGF gene transfer in a rat tail lymphedema model by disruption of lymphatic vessels resulted in a decrease in lymphedema thickness. Although expression of the endothelial cell marker PECAM-1 was increased in both HGF- and vascular endothelial growth factor 165-injected groups, expression of LEC markers (LYVE-1 and Prox1) was increased only in the HGF-injected group. CONCLUSIONS: These data demonstrate that expression of HGF via plasmid transfer improves lymphedema via promotion of lymphangiogenesis. Further studies to determine the clinical utility of this approach would be of benefit to patients with lymphedema.

Animals↗

Hypertension accelerated experimental abdominal aortic aneurysm through upregulation of nuclear factor kappaB and Ets.

In this study, we focused on the effect of hypertension on the transcription factors nuclear factor kappaB (NFkappaB) and ets in the mechanisms of abdominal aortic aneurysm (AAA), and we investigated how hypertension affects the progression of AAA. AAA was produced by elastase perfusion in hypertensive rats and normotensive rats. The size of AAA rapidly increased in hypertensive rats as compared with normotensive rats. Western blot analysis demonstrated that the expression of matrix metalloproteinase (MMP)-2, -3 , -9, and -12, as well as intercellular adhesion molecule, was increased in hypertensive AAA rats, accompanied by upregulation of NFkappaB and ets. Moreover, in situ zymography showed that the activity of MMPs was increased in the aorta of a hypertensive AAA model as compared with that in a normotensive AAA model. Interestingly, transfection of chimeric decoy oligodeoxynucleotide (ODN) resulted in significant inhibition of aortic dilatation both in normotensive and hypertensive rats at 4 weeks after transfection. Destruction of elastic fibers was also significantly inhibited by transfection of chimeric decoy ODN in both hypertensive rats and normotensive rats. The expression of MMP-2, -3, -9, and -12, as well as intercellular adhesion molecule, was significantly attenuated by the chimeric decoy ODN, accompanied by inhibition of the migration of macrophages. Also, the effect of chimeric decoy ODN was confirmed in an organ culture. The present study demonstrated that hypertension accelerated the progression of experimental AAA through upregulation of NFkappaB and ets. Inhibition of NFkappaB and ets could be a novel therapeutic strategy to treat AAA in hypertensive patients.

Animals↗

Targeted anticancer immunotoxins and cytotoxic agents with direct killing moieties.

Despite the progress of the bioinformatics approach to characterize cell-surface antigens and receptors on tumor cells, it remains difficult to generate novel cancer vaccines or neutralizing monoclonal antibody therapeutics. Among targeted cancer therapeutics, biologicals with targetable antibodies or ligands conjugated or fused to toxins or chemicals for direct cell-killing ability have been developed over the last 2 decades. These conjugated or fused chimeric proteins are termed immunotoxins or cytotoxic agents. Two agents, DAB389IL-2 (ONTAKTM) targeting the interleukin-2 receptor and CD33-calicheamicin (Mylotarg), have been approved by the FDA for cutaneous T-cell lymphoma (CTCL) and relapsed acute myeloid leukemia (AML), respectively. Such targetable agents, including RFB4(dsFv)-PE38 (BL22), IL13-PE38QQR, and Tf-CRM107, are being tested in clinical trials. Several agents using unique technology such as a cleavable adapter or immunoliposomes with antibodies are also in the preclinical stage. This review summarizes the generation, mechanism, and development of these agents. In addition, possible future directions of this therapeutic approach are discussed.

ADP Ribose Transferases↗

Inhibitory effects of NFkappaB decoy oligodeoxynucleotides on neointimal hyperplasia in a rabbit vein graft model.

Autologous vein remains the commonly used conduit for bypass grafts; however, neointimal hyperplasia is known to be one of the major disease processes in vein graft failure. In this study, we focused on the important role of NFkappaB which controls the expression of numerous genes for various cytokines and adhesion molecules in the mechanism of graft failure. Thus, we investigated the inhibitory effect of NFkappaB decoy oligodeoxynucleotides (ODN) on vein graft failure in a rabbit hypercholesterolemic model. Jugular vein to carotid artery interposition grafts in rabbits were transfected intraoperatively with NFkappaB decoy ODN (40 micromol/l) by ex-vivo pressure-mediated transfection (300 mm Hg, 10 min). Treatment with NFkappaB decoy ODN significantly suppressed intimal hyperplasia 4 weeks after vein implantation as compared to scrambled decoy ODN, and increased medial thickness, leading to a significant reduction in intima-to-media ratio. Treatment with NFkappaB decoy ODN significantly inhibited the recruitment of macrophages and the proliferation of vascular smooth muscle cells (VSMC), while apoptosis in VSMC was significantly increased by NFkappaB decoy ODN. In addition, a study of vascular reactivity demonstrated that transfection of grafts with NFkappaB decoy ODN significantly improved endothelium-mediated vasorelaxation as compared to scrambled decoy ODN. Here, we demonstrated that inhibition of NFkappaB activation using decoy ODN inhibited the development of neointimal hyperplasia, followed by suppression of inflammatory changes and accumulation of VSMC in the neointima of rabbit vein grafts. The present study raises the possibility of a novel strategy for prevention of graft failure.

Animals↗

Model of vasculogenesis from embryonic stem cells for vascular research and regenerative medicine.

Embryonic stem (ES) cells are highlighted as promising cell sources for regenerative medicine. Here, we focused on providing the platform that forced ES cells to reproduce the vascular organization process, leading to efficiency and safety evaluation as preclinical testing of biological agents. Murine ES cell-derived embryoid bodies on matrigel, but not collagen or gelatin, could be differentiated into sprouting blood vessels without the addition of growth factors. The expression of endothelial cell marker CD31 and smooth muscle marker alpha-smooth muscle actin was partially colocalized and started to increase 7 days after culture on matrigel, accompanied by the induction of a number of growth factors, such as vascular endothelial growth factor, fibroblast growth factor-2, hepatocyte growth factor, transforming growth factor-beta, and angiopoietin-1. Moreover, notch-related genes, such as Del1 or Del4 (delta-like 1/4) and hey1 or hey2 (hairy/enhancer of split related TRPW motif 1/2), were upregulated in a similar time course. The treatment of neutralizing antibodies against these growth factors failed to inhibit the differentiation into the sprouting blood vessels, whereas arginine-glycine-aspartic peptide, a selective inhibitor for the alphavbeta3-integrins, did inhibit differentiation. An anticancer drug to inhibit angiogenesis, TNP-470, also blocked the vascular formation in this model. ES cells could reproduce the vascular organization process on the biosynthetic scaffolds, such as matrigel, without the addition of growth factors. In the future, a human ES-based tissue model would be an optional tool for the screening of pharmaceutical drugs for vascular disease.

Animals↗

The effect of VEGF on blood vessels and blood cells during Xenopus development.

Vascular endothelial growth factor (VEGF) is known to play an essential role in vascular development. We have overexpressed VEGF122 or VEGF170, which are equivalent to mouse VEGF120 and VEGF164, in developing Xenopus embryos. Overexpression of VEGF170 but not VEGF122 demonstrated an absence of expression of hematopoietic markers alpha-globin and GATA-1 but only in the posterior portion of the blood island. Interestingly, strong signals of endothelial markers, msr, fli-1, and tie-2, were detectable in those regions, instead of hematopoietic markers. These results suggested both that injection of VEGF170 resulted in disturbance of vasculogenesis in the posterior portion of the blood island, with excessive production of endothelial cells at the expense of blood cells, and that the anterior and posterior portions of the VBI may have distinct characteristics.

Animals↗

Gene transfer of hepatocyte growth factor gene improves learning and memory in the chronic stage of cerebral infarction.

There is no specific treatment to improve the functional recovery in the chronic stage of ischemic stroke. To provide the new therapeutic options, we examined the effect of overexpression of hepatocyte growth factor (HGF) in the chronic stage of cerebral infarction by transferring the HGF gene into the brain using hemagglutinating virus of Japan envelope vector. Sixty rats were exposed to permanent middle cerebral artery occlusion (day 1). Based on the sensorimotor deficits at day 7, the rats were divided equally into control vector or HGF-treated rats. At day 56, rats transfected with the HGF gene showed a significant recovery of learning and memory in Morris water maze tests (control vector 50+/-4 s; HGF 33+/-5 s; P<0.05) and passive avoidance task (control vector 132.4+/-37.5 s; HGF 214.8+/-26.5 s; P<0.05). Although the total volume of cerebral infarction was not related to the outcome, immunohistochemical analysis for Cdc42 and synaptophysin in the peri-infarct region revealed that HGF enhanced the neurite extension and increased synapses. Immunohistochemistry for glial fibriary acidic protein revealed that the formation of glial scar was also prevented by HGF gene treatment. Additionally, the number of the arteries was increased in the HGF group at day 56. These data demonstrated that HGF has a pivotal role for the functional recovery after cerebral infarction through neuritogenesis, improved microcirculation, and the prevention of gliosis. Our results also provide evidence for the feasibility of gene therapy in the chronic stage of cerebral infarction.

Animals↗

Development of new screening system for Alzheimer disease, in vitro Abeta sink assay, to identify the dissociation of soluble Abeta from fibrils.

Abeta is one of the primary therapeutic targets for Alzheimer disease (AD). Abeta vaccination induces the disappearance of Abeta deposits. Since few reports have focused on the reverse phase of Abeta aggregation, we established a new screening system, the in vitro Abeta sink assay, to clarify the process of dissociation of soluble forms from fibrils. Abeta42 was more resistant to dissociation from fibrils to monomers and/or low molecular weight (LMW) soluble oligomers than Abeta40. We applied this system to find a potential therapy for AD. Ultrasound irradiation significantly enhanced the dissociation of soluble Abeta from fibrils, while ultrasound experiments also confirmed the difference between Abeta40 and Abeta42. We found that some compounds enhanced the dissociation of Abeta from fibrils. Here, we proposed that Abeta42 was more resistant to dissociation from fibrils to monomers and/or LMW soluble oligomers than Abeta40, and this system might be useful to identify dissociation of soluble Abeta from fibrils.

Alzheimer Disease↗

HVJ-based non-viral gene transfer method: successful gene therapy using HGF and VEGF genes in experimental ischemia.

VEGF and HGF are pleiotropic factors that regulate cell growth, cell motility, and morphogenesis of various types of cells. The receptors of these growth factors are expressed in neurons and endothelial cells, and are identified as neurotrophic, neuroprotective, and angiogenic factors. Indeed, gene therapy using viral vectors encoding the VEGF or HGF gene has been reported to be effective for preventing the expansion of ischemic injury. However, the safety issue of viral vectors is a major problem in clinical application. To overcome this problem, we have developed an HVJ-based non-viral vector, which achieves high-efficiency transfection rates of viral vectors with the safety of liposomes. This review discusses the feasibility of gene therapy using an HVJ-based non-viral vector containing the VEGF or HGF gene for cerebral ischemia.

Animals↗

Development of high-throughput functional screening of therapeutic genes, using a hemagglutinating virus of Japan envelope vector.

Isolation of effective therapeutic genes is critical for the advancement of gene therapy for various diseases, including vascular diseases and cancers. The goal of the present study was to screen a human cDNA library, using a hemagglutinating virus of Japan envelope (HVJ-E) vector, to isolate candidate genes with potent therapeutic potential. The advantages of a high-throughput functional screening system based on the HVJ-E vector include (1) rapid preparation of the vector containing the DNA library, (2) effective fusion-mediated transfer of the plasmids to various cells with minimal toxicity, and (3) easy cloning of candidate genes by transformation of Escherichia coli. These advantages resulted in a lower probability of damage to isolated clones and in minimization of the time needed to screen for candidate genes. Screening of a human heart library for candidate genes to regulate endothelial cell growth identified three growth-stimulating genes, as evaluated by 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) assay and c-fos promoter activity, the products of which were more potent than vascular endothelial growth factor. Similarly, two growth-inhibiting genes were identified, the effects of which were similar to angiostatin. Overall, this novel system will help advance our understanding of cell biology and promote the utility of human gene therapy.

Cell Line↗

Inhibitory effect of ribbon-type NF-kappaB decoy oligodeoxynucleotides on osteoclast induction and activity in vitro and in vivo.

In this study we examined the effect of ribbon-type (circular-type) NF-kappaB decoy oligodeoxynucleotides (RNODN) on osteoclast induction and activity. We extracted bone marrow cells from the femurs of rats and incubated non-adherent cells with receptor activator of nuclear factor kappaB ligand (RANKL) and macrophage colony-stimulating factor (M-CSF). First, transfer efficiency into osteoclasts and their precursors, resistance to exonuclease, and binding activity of decoy to NF-kappaB were examined. Next, to examine the effect of RNODN on osteoclast induction and activity, osteoclast differentiation and pit formation assays were performed. RNODN were injected into the ankle joints of rats with collagen-induced arthritis. Joint destruction and osteoclast activity were examined by histological study. The resistance of RNODN to exonuclease and their binding activity on NF-kappaB were both greater than those of phosphorothionated NF-kappaB decoy oligodeoxynucleotides. The absolute number of multinucleate cells scoring positive for tartrate-resistant acid phosphatase was significantly decreased in the RNODN-treated group. The average calcified matrix resorbed area was significantly decreased in the RNODN-treated group. Histological study showed marked suppression of joint destruction and osteoclast activity by intra-articular injection of RNODN. These results suggest the inhibitory effect of RNODN on the induction and activity of osteoclasts. Direct intra-articular injection of RNODN into the joints may be an effective strategy for the treatment of arthritis.

Animals↗

[Development of plasmid DNA-based gene transfer].

Gene therapy based on ultrasound with microbubbles offers a novel approach for the prevention and treatment of variety of diseases. The major development of gene transfer has importantly contributed to intense investigation of the potential of gene therapy in cancer or cardiovascular medicine. The amazing advances in molecular biology have provided a dramatic improvement of the technology that is necessary to transfer target genes into somatic cells. Gene transfer methods have been surprisingly improved. In fact, some of them (retroviral vectors, adenoviral vectors or liposome based vectors, etc.) have been used in the clinical trials already. But some severe side effects were reported in clinical gene therapy using such viral, so people desire safe and efficient clinical gene therapy. Recently, ultrasound-mediated gene transfer has been reported to augment the transfection efficiency and facilitate local gene expression. Interestingly, gene transfer into the fetal central nervous system was successfully achieved by intrauterine injection with microbubble-enhanced ultrasound. Compared to other viral vectors, there are some theoretical advantages including safety, simplicity of preparation, and local gene transfer. Thus, we focused on the development of gene transfer using naked plasmid DNA with an ultrasound or microbubble-enhanced ultrasound method.

Animals↗

Anti-oxidant gene therapy by NF kappa B decoy oligodeoxynucleotide.

Oxidative stress to cardiovascular cells induced by an interaction of multiple cytokines and adhesion molecules has been postulated to be responsible for cardiovascular disease. Since nuclear factor-kappaB (NFkappaB) also plays a pivotal role in the coordinated transactivation of cytokine and adhesion molecule genes, we utilized oligodeoxynucleotides (ODNs) as "decoy" cis-elements that block the binding of nuclear factors to promoter regions of targeted genes, resulting in the inhibition of gene transactivation. Indeed, transfection of NFkappaB decoy ODNs into coronary artery effectively prevented transactivation of essential cytokine and adhesion molecule protein expression, and thereby protected the myocardium from infarction. Transfection of NFkappaB decoy ODNs into balloon-injured carotid artery or porcine coronary artery markedly reduced neointimal formation. Thus, a clinical trial using NFkappaB decoy ODNs to treat restenosis was started in 2002. Recently, the therapeutic target utilizing NFkappaB decoy has been expanded to glomerulonephritis, rheumatoid arthritis, atopic dermatitis and osteoporosis. Moreover, the clinical trials to treat RA patients were initiated in 2003 and a Phase I/IIa human clinical trial using NFkappaB decoy ODNs to treat atopic dermatitis was initiated in December 2001. Topical application of NFkappaB decoy ODNs exhibited marked therapeutic effects on the facial skin condition of patients with atopic dermatitis. The covalently modified ODNs were developed by enzymatically ligating two identical molecules, thereby preventing their degradation by exonucleases. Indeed, the modified decoy ODNs possess increased nuclease resistance and are transported more efficiently into cells. Although there are still unresolved issues, decoy ODN drugs should become a reality.

Animals↗

Adipose tissue-derived stromal cells as a novel option for regenerative cell therapy.

Adult stem cells hold great promise for use in tissue repair and regeneration, and the delivery of autologous progenitor cells into ischemic tissue is emerging as a novel therapeutic option. We and others have recently demonstrated the potential impact of adipose tissue-derived stromal cells (ADSC) on regenerative cell therapy for ischemic diseases. The main benefit of ADSC is that they can be easily harvested from patients by a simple, minimally invasive method and also easily cultured. Cultured ADSC can be induced to differentiate into not only adipocytes, but also bone, neurons or endothelial cells in certain conditions. Interestingly, they secrete a number of angiogenesis-related cytokines, such as vascular endothelial growth factor (VEGF) and hepatocyte growth factor (HGF), which might be suitable for regenerative cell therapy for ischemic diseases. In the ischemic mouse hindlimb, the angiogenic score was improved in the ADSC-treated group. Moreover, recent reports demonstrated that these ADSC can also be induced to differentiate into cardiac myocytes. These adipose tissue-derived cells have potential in angiogenic cell therapy for ischemic disease, and might be applied for regenerative cell therapy instead of bone marrow cells in the near future.

Adipose Tissue↗

[Therapeutic angiogenesis for ischemic diseases].

The clinical consequences of peripheral arterial disease include pain on walking, pain at rest and loss of tissue integrity in the distal ischemic limbs. Although development of beneficial drugs and intervention devices do contribute to the treatment of this disease, critical limb ischemia is estimated to develop in 500 to 1,000 individuals per million per year. As angiogenic growth factors can stimulate the development of collateral arteries, a concept called "therapeutic angiogenesis" is now evaluated in the clinical fields. Recent progress in molecular biology has led to the development of gene therapy as a new strategy to treat a variety of cardiovascular diseases using angiogenic growth factors such as vascular endothelial growth factor (VEGF). Therapeutic angiogenesis using angiogenic growth factors is expected to be a new treatment for patients with severe ischemic heart or peripheral arterial disease.

Angiogenesis Inducing Agents↗

E2F decoy oligodeoxynucleotide ameliorates cartilage invasion by infiltrating synovium derived from rheumatoid arthritis.

This study examined the ability of E2F decoy oligodeoxynucleotides (ODN) to inhibit proliferation of synovial fibroblasts derived from patients with rheumatoid arthritis (RA). The effect of E2F decoy ODN on cartilage invasion by RA synovium in a murine model of human RA was also investigated. E2F decoy ODN were introduced into synovial tissue and synovial fibroblasts derived from patients with RA using hemagglutinating virus of Japan (HVJ)-liposomes. The effect of E2F decoy ODN on synovial fibroblast proliferation was evaluated by MTT assay and by RT-PCR for the cell cycle regulatory genes proliferating-cell nuclear antigen (PCNA) and cyclin-dependent kinase 2 (cdk2). Changes in production of inflammatory mediators by RA synovial tissue following transfection with E2F decoy ODN were assessed by ELISA. Human cartilage and RA synovial tissue transfected with E2F decoy ODN were co-transplanted in severe combined immunodeficient (SCID) mice. After 4 weeks, the mice were sacrificed and the implants histologically examined for inhibition of cartilage damage by E2F decoy ODN. E2F decoy ODN resulted in significant inhibition of synovial fibroblast proliferation, corresponding with reduced expression of PCNA and cdk2 mRNA in synovial fibroblasts. The production of interleukin-1beta (IL-1beta), IL-6 and matrix metalloproteinase (MMP)-1 by synovial tissue was also significantly inhibited by the introduction of E2F decoy ODN. Further, in an in vivo model, cartilage that was co-implanted with RA synovial tissue transfected with E2F decoy ODN exhibited no invasive and progressive cartilage degradation. These data demonstrate that transfection of E2F decoy ODN prevents cartilage destruction by inhibition of synovial cell proliferation, and suggest that transfection of E2F decoy ODN may provide a useful therapeutic approach for the treatment of joint destruction in arthritis.

Animals↗