Hiroyuki Kagechika

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The molecular basis of CNS myelin regeneration (remyelination) is poorly understood. We generated a comprehensive transcriptional profile of the separate stages of spontaneous remyelination that follow focal demyelination in the rat CNS and found that transcripts that encode the retinoid acid receptor RXR-γ were differentially expressed during(More)
The vitamin A metabolite, retinoic acid (RA), affects Th1 and Th2 development. The effect is partly exerted through the modulation of antigen-presenting cell functions, but it remains unclear whether RA directly exerts its effect on T cells to influence Th1/Th2 development. To clarify this problem, we used two experimental systems with isolated T cells in(More)
Genipin, a herbal iridoid, is known to have both neuroprotective and neuritogenic activity in neuronal cell lines. As it is structurally similar to tetrahydrobiopterin, its activity is believed to be nitric oxide (NO)-dependent. We previously proposed a novel neuroprotective activity of a genipin derivative, (1R)-isoPropyloxygenipin (IPRG001), whereby it(More)
Vitamin A-derived retinoic acids (RAs) are known to exert a variety of biological actions, including modulatory effects on cell differentiation and apoptosis. A recent study has demonstrated that 13-cis-RA and all-trans-RA suppressed neurogenesis in the dentate gyrus of the hippocampus in adult mice. The present experiments were performed to see whether(More)
Retinoids influence cellular processes such as differentiation, proliferation and apoptosis via retinoic acid receptor (RAR) and retinoid X receptor (RXR), and have therapeutic applications in several cancers and dermatologic diseases. Recent reports indicate that depression occasionally occurs in patients using the acne drug Accutane, the active component(More)
Vitamin A metabolites, such as all-trans-retinoic acid (RA) that act through the nuclear receptor; retinoic acid receptor (RAR), have been shown to polarise T cells towards Th2, and to be important in resistance to helminth infections. Co-incidentally, people harbouring intestinal parasites are often supplemented with vitamin A, as both vitamin A deficiency(More)
The aim of this study was to evaluate, in comparison with melatonin (MLT), the effects of a novel 2-melatonin derivative, having a 2-trifluoromethyl group (MLTD) on the sleep-wake cycle in freely behaving rats. Doses of MLTD (100, 300 and 500 nmol/100 microl saline) or MLT (500 nmol/100 microl saline) replaced the i.c.v. infusion of saline during the(More)
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