An issue in drug discovery research at pharmaceutical companies is the decline in the probability of market launch, and there is a need to improve the proof-of-concept (POC) acquisition rate by further improving clinical predictability. For this purpose, we need to deepen our understanding of human pathophysiology, and to make efficient of drug discovery research by utilizing human samples and data due to the change in mindset from "animals" to "humans" at the drug discovery research stage. In particular, with the aim of improving the efficiency of drug discovery research by utilizing human samples/data, we have established a human sample utilization support capability, then we are supporting the acquisition of appropriate human samples/data to meet each drug research need with collecting information on organizations that can provide various human samples and accumulating know-how on obtaining human samples/data.
View Article and Find Full Text PDFPurpose: To evaluate the feasibility of using DARC (detection of apoptosing retinal cells) technology as a biomarker for preclinical assessment of glaucomatous damage in a non-human primate (NHP) model of ocular hypertension (OHT).
Methods: Elevated intraocular pressure (IOP) was induced by applying a laser to the trabecular meshwork in each eye of NHPs. Changes in DARC counts in the retina, identified as fluorescent-tagged annexin V (ANX776)-positive cells, were evaluated together with optic nerve damage, assessed using spectral domain-optical coherence tomography.
In patients with lepromatous leprosy, Mycobacterium leprae is often observed inside the human microvascular endothelial cells (HMVEC) surrounding Schwann cells (SC) at the site of lesions in the peripheral nerves. Based on this observation, it is considered that the nasal mucous may be the invasion pathway for M. leprae and HMVEC serve as an important reservoir for the bacteria before they invade SC.
View Article and Find Full Text PDFLeprosy is a chronic infection where the skin and peripheral nervous system is invaded by Mycobacterium leprae. The infection mechanism remains unknown in part because culture methods have not been established yet for M. leprae.
View Article and Find Full Text PDFDermcidin (DCD), an antimicrobial peptide with a broad spectrum of activity against bacteria such as Propionibacterum acnes, is expressed constitutively in sweat in the absence of stimulation due to injury or inflammation. The aim of this study was to determine the relationship between DCD expression and acne vulgaris associated with P. acnes.
View Article and Find Full Text PDFTrichophytosis, a common dermatophytosis, affects nearly 20-25% of the world's population. However, little is known about mechanisms for preventing colonization of Trichophyton on the skin. Dermcidin, an antimicrobial peptide that provides innate immunity to the skin and is constitutively secreted even in the absence of inflammatory stimulation, was studied to elucidate its antimycotic activity against Trichophyton.
View Article and Find Full Text PDFHes genes are required to maintain diverse progenitor cell populations during embryonic development. Loss of Hes1 results in a spectrum of malformations of pharyngeal endoderm-derived organs, including the ultimobranchial body (progenitor of C cells), parathyroid, thymus and thyroid glands, together with highly penetrant C-cell aplasia (81%) and parathyroid aplasia (28%). The hypoplastic parathyroid and thymus are mostly located around the pharyngeal cavity, even at embryonic day (E) 15.
View Article and Find Full Text PDFThe lack of the Hes1 gene leads to the failure of cranial neurulation due to the premature onset of neural differentiation. Hes1 homozygous null mutant mice displayed a neural tube closure defect, and exencephaly was induced at the mid/hindbrain boundary. In the mutant mesencephalon, the roof plate was not formed and therefore the ventricular zone showing cell proliferation was displaced to the brain surface.
View Article and Find Full Text PDFNihon Hansenbyo Gakkai Zasshi
September 2008
The long search of an animal model for leprosy were carried out as many researchers since the Mycobacterium leprae discovery by Dr. Hansen in 1874. The remarkable results were left after the development of the foot-pad method by Dr.
View Article and Find Full Text PDFHistone deacetylase (HDAC) inhibitors repress interleukin-2 (IL-2) gene expression in T cells and possess immunosuppressive activity in vivo. In addition to its immunosuppressive activity, HDAC inhibitors block GATA binding protein-1 (GATA-1) gene expression in megakaryocytes and elicit thrombocytopenia. In this report we state that for a given immunosuppressive dose of HDAC inhibitor, the ratio of GATA-1 reporter gene activity relative to IL-2 reporter gene assay (G/I ratio of measured IC(50)) can be predictive of a HDAC inhibitor's thrombocytopenic effect.
View Article and Find Full Text PDFInterleukin (IL)-2 is an essential cytokine in T cell proliferation and homeostasis. The importance of IL-2 down-regulation in preventing acute rejection in organ transplantation and the development of autoimmune diseases has been demonstrated by the therapeutic usefulness of the widely used immunosuppressants cyclosporine A and FK506. Recently, a histone deacetylase (HDAC) inhibitor, FR235222, has been shown to inhibit IL-2 gene expression and to possess immunosuppressive activity in vivo.
View Article and Find Full Text PDFHistone deacetylase inhibitors (HDAC inhibitors) are an emerging class of anticancer agents. To elucidate the mechanism of HDAC inhibitor-induced thrombocytopenia, we focused on the effects of HDAC inhibitors on megakaryocyte differentiation and performed Affymetrix GeneChip analysis of human megakaryocytic HEL cells treated with or without HDAC inhibitors. Here, we report that GATA-1 and 10 haematopoietic factors (SCL, NF-E2, EKLF, Pleckstrin, Thrombin-R, LMO2, PU.
View Article and Find Full Text PDFPrevious studies have shown that HDAC inhibitors selectively inhibit IL-2 gene expression, but the mechanism of this inhibition remains to be elucidated. It was recently reported that HDAC4, a component of the nuclear hormone receptor corepressor (N-CoR) complex, associates with the IL-2 promoter via the transcription factor myocyte enhancer factor 2 (MEF2). We therefore focused on the role of HDAC4/N-CoR complex in the transcriptional regulation of IL-2.
View Article and Find Full Text PDFIn order to know how caspases contribute to the intracellular fate of Mycobacterium tuberculosis and host cell death in the infected macrophages, we examined the effect of benzyloxycarbonyl-Val-Ala-Asp(OMe)-fluoromethane (z-VAD-fmk), a broad-spectrum caspase inhibitor, on the growth of M. tuberculosis H37Rv in RAW 264 cells. In the cells treated with z-VAD-fmk, activation of caspase-8, caspase-3/7, and caspase-9 was clearly suppressed, and DNA fragmentation of the infected cells was also reduced.
View Article and Find Full Text PDFBackground: The transmission of Mycobacterium leprae, the causative pathogen of leprosy, has been postulated to occur mainly through upper respiratory route rather than skin-to-skin contact via minor injuries. The M. leprae genome contains mce1A gene, which encodes a putative mammalian cell entry protein.
View Article and Find Full Text PDFMycobacterial mammalian cell entry protein 1A (Mce1A) is involved in the uptake of bacteria in non-phagocytic cells and also possibly in granuloma formation. However, it has not been clarified whether the interaction between mycobacterial Mce1A and epithelial cell induces chemokine and cytokine production which is required for granuloma formation. To this end, we infected A549 alveolar epithelial cells in vitro with E.
View Article and Find Full Text PDFAcridine orange (AO), a weakly basic fluorescent dye, is permeable to plasma and vesicle membranes and preferentially remains in intracellular acidic regions. Using fluorescence microscopy, we observed dynamic changes in AO-loaded cultured malignant melanoma cells during illumination with blue light. Immediately after the start of the illumination, the successive disruption of vesicles was observed as a flash of fluorescence, and shortly after that, blebs were formed on the plasma membrane.
View Article and Find Full Text PDFAdipogenesis is an important process for the improvement of insulin resistance by peroxisome proliferator-activated receptor (PPAR) gamma agonists, such as rosiglitazone and pioglitazone. FK614 [3-(2,4-dichlorobenzyl)-2-methyl-N-(pentylsulfonyl)-3-Hbenzimidazole-5-carboxamide] is a structurally novel class of PPARgamma agonist that improves insulin sensitivity in animal models of type 2 diabetes. Herein, we characterize FK614, a selective PPARgamma modulator (SPPARM) with differential properties affecting the regulation of fat cell function.
View Article and Find Full Text PDFFK614 is a structurally novel class of peroxisome proliferator-activated receptor gamma (PPARgamma) agonist, with the mechanism of its insulin-sensitizing action most likely due to activation of PPARgamma. In this study, properties of FK614 for PPARgamma binding, ability to induce conformational change, and coactivator recruitment were investigated. FK614, rosiglitazone, and pioglitazone competed specific binding of [3H]rosiglitazone to PPARgamma with Ki values of 11 nM, 47 nM, and 1.
View Article and Find Full Text PDFPeroxisome proliferator-activated receptor gamma (PPARgamma) is a ligand-dependent transcriptional factor implicated in regulating adipogenesis, glucose homeostasis, and in mediating the action of the insulin sensitizing anti-diabetic thiazolidinedione (TZD) compounds. [3-(2,4-Dichlorobenzyl)-2-methyl-N-(pentylsulfonyl)-3-H-benzimidazole-5-carboxamide] (FK614) is a structurally novel PPARgamma agonist that demonstrates potent anti-diabetic activity in vivo. Herein, we describe that FK614 is a selective PPARgamma ligand with specific transactivation properties that are dependent upon the context of coactivators.
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