Transplanted bone marrow stromal cells protect neurovascular units and ameliorate brain damage in stroke-prone spontaneously hypertensive rats. Masaki Ito,Satoshi Kuroda,Taku Sugiyama,Katsuhiko Maruichi,Masahito Kawabori,Naoki Nakayama,Kiyohiro Houkin,Yoshinobu Iwasaki Neuropathology : official journal of the Japanese Society of Neuropathology
32
2011
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This study was aimed to assess whether bone marrow stromal cells (BMSC) could ameliorate brain damage when transplanted into the brain of stroke-prone spontaneously hypertensive rats (SHR-SP). The BMSC or vehicle was stereotactically engrafted into the striatum of male SHR-SP at 8 weeks of age. Daily loading with 0.5% NaCl-containing water was started from 9 weeks. MRIs and histological analysis were performed at 11 and 12 weeks, respectively. Wistar-Kyoto rats were employed as the control. As a result, T2-weighted images demonstrated neither cerebral infarct nor intracerebral hemorrhage, but identified abnormal dilatation of the lateral ventricles in SHR-SP. HE staining demonstrated selective neuronal injury in their neocortices. Double fluorescence immunohistochemistry revealed that they had a decreased density of the collagen IV-positive microvessels and a decreased number of the microvessels with normal integrity between basement membrane and astrocyte end-feet. BMSC transplantation significantly ameliorated the ventricular dilatation and the breakdown of neurovascular integrity. These findings strongly suggest that long-lasting hypertension may primarily damage neurovascular integrity and neurons, leading to tissue atrophy and ventricular dilatation prior to the occurrence of cerebral stroke. The BMSC may ameliorate these damaging processes when directly transplanted into the brain, opening the possibility of prophylactic medicine to prevent microvascular and parenchymal-damaging processes in hypertensive patients at higher risk for cerebral stroke. | 22239468
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Effects of 530 nm Green Light on Refractive Status, Melatonin, MT1 Receptor, and Melanopsin in the Guinea Pig. Wang F, Zhou J, Lu Y, Chu R Curr Eye Res
36
103-11. Epub 2010 Dec 15.
2010
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Purpose: To investigate (i) the effect of monochromatic light on inhibiting induction of light-induced melatonin and (ii) the roles of melanopsin and MT1 receptor in light-induced myopia in the guinea pig. Methods: Forty-eight guinea pigs were randomly distributed into three treatment groups: white-light (control), green-light (530 nm), and blue-light (480 nm) groups. Levels of pineal gland melatonin were measured twice daily-10:00 a.m. and 10:00 p.m.-10 days after initial light treatment. Thirty additional guinea pigs were also assigned to these groups and treated similarly. For these latter animals, refractive status, ocular length, and vitreous depth were measured before and after light treatment. Eight weeks after light treatment, retinal and sceral levels of melanopsin, melatonin receptor type (MT) 1, and mRNA protein were determined by Western blotting, real-time polymerase chain reaction (RT-PCR), and immunohistochemistry. Results: The level of pineal gland melatonin in the green-light group was significantly higher than that in the blue-light group. Biometric measurements showed that guinea pigs in the green-light group had a somewhat myopic refractive status. Expressions of retinal melanopsin mRNA and protein were significantly higher in the blue-light group and lower in the green-light group when compared to controls. Conversely, expressions of MT1 receptor mRNA and protein in retina and sclera were significantly higher in the green-light group and lower in the blue-light group when compared to controls. Conclusions: Green light appears to suppress induction of melatonin production. In addition, 530 nm of green light is involved in the development of myopia. In the guinea pig, MT1 receptor and melanopsin appear to play roles in the development of myopia induced by 530 nm of light. | 21158589
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Suppression of canonical Wnt/beta-catenin signaling by nuclear plakoglobin recapitulates phenotype of arrhythmogenic right ventricular cardiomyopathy. Garcia-Gras, E; Lombardi, R; Giocondo, MJ; Willerson, JT; Schneider, MD; Khoury, DS; Marian, AJ The Journal of clinical investigation
116
2012-21
2005
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Arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVC) is a genetic disease caused by mutations in desmosomal proteins. The phenotypic hallmark of ARVC is fibroadipocytic replacement of cardiac myocytes, which is a unique phenotype with a yet-to-be-defined molecular mechanism. We established atrial myocyte cell lines expressing siRNA against desmoplakin (DP), responsible for human ARVC. We show suppression of DP expression leads to nuclear localization of the desmosomal protein plakoglobin and a 2-fold reduction in canonical Wnt/beta-catenin signaling through Tcf/Lef1 transcription factors. The ensuing phenotype is increased expression of adipogenic and fibrogenic genes and accumulation of fat droplets. We further show that cardiac-restricted deletion of Dsp, encoding DP, impairs cardiac morphogenesis and leads to high embryonic lethality in the homozygous state. Heterozygous DP-deficient mice exhibited excess adipocytes and fibrosis in the myocardium, increased myocyte apoptosis, cardiac dysfunction, and ventricular arrhythmias, thus recapitulating the phenotype of human ARVC. We believe our results provide for a novel molecular mechanism for the pathogenesis of ARVC and establish cardiac-restricted DP-deficient mice as a model for human ARVC. These findings could provide for the opportunity to identify new diagnostic markers and therapeutic targets in patients with ARVC. Article en texte intégral | 16823493
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Characterization of pancreatic stem cells derived from adult human pancreas ducts by fluorescence activated cell sorting. Lin, HT; Chiou, SH; Kao, CL; Shyr, YM; Hsu, CJ; Tarng, YW; Ho, LL; Kwok, CF; Ku, HH World journal of gastroenterology
12
4529-35
2005
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To isolate putative pancreatic stem cells (PSCs) from human adult tissues of pancreas duct using serum-free, conditioned medium. The characterization of surface phenotype of these PSCs was analyzed by flow cytometry. The potential for pancreatic lineage and the capability of beta-cell differentiation in these PSCs were evaluated as well.By using serum-free medium supplemented with essential growth factors, we attempted to isolate the putative PSCs which has been reported to express nestin and pdx-1. The Matrigel(TM) was employed to evaluate the differential capacity of isolated cells. Dithizone staining, insulin content/secretion measurement, and immunohistochemistry staining were used to monitor the differentiation. Fluorescence activated cell sorting (FACS) was used to detect the phenotypic markers of putative PSCs.A monolayer of spindle-like cells was cultivated. The putative PSCs expressed pdx-1 and nestin. They were also able to differentiate into insulin-, glucagon-, and somatostatin-positive cells. The spectrum of phenotypic markers in PSCs was investigated; a similarity was revealed when using human bone marrow-derived stem cells as the comparative experiment, such as CD29, CD44, CD49, CD50, CD51, CD62E, PDGFR-alpha, CD73 (SH2), CD81, CD105(SH3).In this study, we successfully isolated PSCs from adult human pancreatic duct by using serum-free medium. These PSCs not only expressed nestin and pdx-1 but also exhibited markers attributable to mesenchymal stem cells. Although work is needed to elucidate the role of these cells, the application of these PSCs might be therapeutic strategies for diabetes mellitus. | 16874866
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Phenylethanolamine-N-methyltransferase - immunoreactive nerve terminals afferent to the mouse substantia nigra. I Nagatsu, K Ikemoto, T Takeuchi, R Arai, N Karasawa, T Fujii, T Nagatsu Neuroscience letters
245
41-4
1998
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In the substantia nigra pars compacta, many phenylethanolamine-N-methyltransferase immunoreactive (PNMT-ir) terminals as well as serotonin-ir terminals were observed for the first time to be very closely situated to the tyrosine hydroxylase (TH)-ir, aromatic L-amino acid decarboxylase-ir, and GTP cyclohydrolase I (GCH)-ir dopaminergic cells [Nagatsu, I., Arai, R., Sakai, M., Yamawaki, Y., Takeuchi, T., Karasawa, N. and Nagatsu, T., Neurosci. Lett., 224 (1997) 185-188]. Immunohistochemical colocalization of TH with GCH or PNMT in the somata and dendrites of TH-positive neurons in the rostral ventrolateral reticular formation of the medulla oblongata (C1 region, [Hokfelt, T., Fuxe, K., Goldstein, M. and Johansson, O., Brain Res., 66 (1974) 235-251]) was proved by a double-labeling immunofluorescence method with a confocal laser-scanning microscope, indicating that the neurons are adrenergic. These results suggest that dopaminergic neurons in the substantia nigra receive PNMT-ir, adrenergic afferents from the C1 region of the medulla oblongata. | 9596351
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