Publications by authors named "Kentaro Kitadate"

Background: Perilla (Perilla frutescens Britton) leaf comprises many types of active components, mainly flavonoids, and acts as an anti-inflammatory agent in in vitro and in vivo atopic dermatitis (AD) models.

Objective: We investigated the effects of orally administered perilla leaf extract (PLE) on the symptoms of AD induced by Dermatophagoides farinae extract (DFE) in NC/Nga AD model mice.

Methods: The mice were allowed free intake of 0.

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One of the pathological characterizations of Alzheimer's disease (AD) is the deposition of amyloid beta peptide (Abeta) in cerebral cortical cells. The deposition of Abeta in neuronal cells leads to an increase in the production of free radicals that are typified by reactive oxygen species (ROS), thereby inducing cell death. A growing body of evidence now suggests that several plant-derived food ingredients are capable of scavenging ROS in mammalian cells.

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Increases in the number of patients with dementia involving Alzheimer's disease (AD) are seen as a grave public health problem. In neurodegenerative disorders involving AD, biological stresses, such as oxidative and inflammatory stress, induce neural cell damage. Asparagus (Asparagus officinalis) is a popular vegetable, and an extract prepared from this reportedly possesses various beneficial biological activities.

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Oligonol is a functional food containing catechin-type monomers and proanthocyanidin oligomer converted from polymer forms via a novel manufacturing process. The catechin component of green tea extract has been associated with nasal toxicity in rats following subchronic exposure. To assess the potential for Oligonol to induce nasal toxicity a 13-week repeated oral dose toxicity study was conducted in rats using doses of 100, 300, and 1000 mg/kg/d.

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Recently, the ability of polyphenols to reduce the risk of dementia and Alzheimer's disease (AD) has attracted a great deal of interest. In the present study, we investigated the attenuating effects of oligomerised lychee fruit-derived polyphenol (OLFP, also called Oligonol) on early cognitive impairment. Male senescence-accelerated mouse prone 8 (SAMP8) mice (4 months old) were given OLFP (100 mg/kg per d) for 2 months, and then conditioned fear memory testing was conducted.

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The results obtained from our previous study showed that the addition of a lychee fruit-derived low molecular form of polyphenol, Oligonol, provoked higher levels of lipolytic activity via the degradation of perilipin 1 in primary rat adipocytes. In the current study, we investigated the possible mechanisms by which Oligonol could promote the degradation of perilipin 1 protein. The addition of Oligonol caused the degradation of GFP-tagged perilipin 1 in a time-dependent manner.

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Oligonol is a lychee fruit-derived low-molecular form of polyphenol. In this study, the effect of Oligonol on the mitogen activated-protein kinase (MAPK) signaling pathway in primary adipocytes was investigated to examine the mechanism underlying the enhanced levels of phosphorylated extracellular-signaling regulatory kinase1/2 (ERK1/2) that accompany an in vitro increase in lipolysis. Oligonol significantly elevated the levels of activated Ras and the phosphorylation of Raf-1 and MAPK/ERK kinase1/2 (MEK1/2) with no increase in pan-Raf-1 and -MEK1/2 proteins.

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Several polyphenols have been shown to be beneficial in preventing the accumulation of body fat in mammals. This paper reports that adding oligonol, a lychee fruit-derived low-molecular form of polyphenol mixture, has a greater effect on lipolysis in primary adipocytes compared with tea (-)-epigallocatechin-3-gallate (EGCG) alone, accompanied by a significant increase in activation of extracellular signalling-related kinase 1/2 (ERK1/2). However, neither phosphorylation of mitogen-activated protein kinase 1/2 (MEK1/2), a molecule upstream of ERK1/2, nor the level of heme oxygenase-1 (HO-1), a molecule downstream of ERK1/2 was significantly changed between oligonol and EGCG, although the addition of oligonol and EGCG significantly increased the levels of phosphorylated MEK1/2 and HO-1 compared with the non-treated control cells.

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We assessed the potential of oligonol, a low molecular polyphenol formulation prepared from lychee fruits, for treatment of oral candidiasis using a murine model. Oligonol at concentration of more than 313 microg/ml inhibited the mycelial growth of Candida albicans in vitro. When 50 microl of oligonol (20 mg/ml ) was administered three times into the oral cavity of orally Candida -infected mice, the number of viable Candida cells in the oral cavity was reduced significantly and the score of lesions on the tongue recovered on day 2.

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The effect of Oligonol, a phenolic product from lychee fruit polyphenol (LFP) containing catechin-type monomers and lower oligomers of proanthocyanidin, on lipolysis in primary adipocytes was investigated in order to examine the possible mechanism underlying the regulation of in vivo metabolism in fat. Oligonol significantly increased lipolysis, which was accompanied by both activation of extracellular signaling-related kinase 1/2 (ERK1/2) and down-regulation of perilipin protein expression, without an increase in intracellular cAMP production. The increase in lipolysis with Oligonol was prevented completely by pretreatment with either PD98059 or U0126, selective ERK1/2 inhibitors, which also prevented the reduction in the expression of perilipin protein.

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Macrophage infiltration of white adipose tissue (WAT) is implicated in the metabolic complications of obesity. In addition, inflammatory changes through dysregulated expression of inflammation-related adipokines such as tumor necrosis factor-alpha (TNF-alpha) and monocyte chemoattractant protein-1 (MCP-1) in WAT are considered to be one of the causes of insulin resistance. Recently, enhanced oxidative stress in adipocytes has been reported to be implicated in dysregulated expression of inflammation-related adipokines.

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Objectives: The main objective of this study is to clarify the protective effects of buckwheat hull extract (BWHE) against toxicant-induced spatial memory impairment and hippocampal neuron injury in rats.

Methods: Male Sprague-Dawley (Jsl: SD) rats were fed chow containing 0.75% (w/w) BWHE during the experimental period.

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