Kiyoshi Sugiyama

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We have previously reported the effects of Kaempferia parviflora (KP), including anti-obesity, preventing various metabolic diseases, and regulating differentiation of white adipose cells. In this study we used Tsumura, Suzuki, Obese Diabetes (TSOD) mice—an animal model of spontaneous obese type II diabetes—and primary brown preadipocytes to examine the(More)
Acacia polyphenol (AP) extracted from the bark of the black wattle tree (Acacia meansii) is rich in unique catechin-like flavan-3-ols, such as robinetinidol and fisetinidol. The present study investigated the anti-obesity/anti-diabetic effects of AP using obese diabetic KKAy mice. KKAy mice received either normal diet, high-fat diet or high-fat diet with(More)
Acacia polyphenol (AP) extracted from the bark of the black wattle tree (Acacia mearnsii) is rich in unique catechin-like flavan-3-ols, such as robinetinidol and fisetinidol. In an in vitro study, we measured the inhibitory activity of AP on lipase and glucosidase. In addition, we evaluated the effects of AP on absorption of orally administered olive oil,(More)
We examined the inhibitory effect of polyphenol-rich aqueous extract from the bark of Acacia mearnsii (PrA) on itching associated with atopic dermatitis (AD). HR-1 mice were fed a normal diet, special diet (AD group), or special diet containing 3% PrA (PrA group) for 6 weeks. In the AD group, itching frequency and transepidermal water loss increased(More)
The chronic administration of morphine to patients with neuropathic pain results in the development of a gradual tolerance to morphine. Although the detailed mechanism of this effect has not yet been elucidated, one of the known causes is a decrease in μ-opioid receptor function with regard to the active metabolite of morphine,(More)
Aquaporins (AQPs) play important roles in the water transport system in the human body. There are currently 13 types of AQP, AQP0 through AQP12, which are expressed in various organs. Many members of the AQP family are expressed in the intestinal tract. AQP3 is predominantly expressed in the colon, ultimately controlling the water transport. Recently, it(More)
It is known that morphine is less effective for patients with neuropathic pain, accounting for approximately 70% of cancer patients with severe pain. One of the causes of the decline is reported as a decreased function of the μ-opioid receptor, which binds to the active metabolites of morphine in the mesencephalic ventral tegmental area. However, the(More)
Neuropathic pain is a chronic condition resulting from neuronal damage. Pregabalin, the (S)-isomer of 3-isobutyl-γ-aminobutyric acid (GABA), is widely used to treat neuropathic pain, despite the occurrence of central nervous system (CNS)-related side effects such as dizziness and somnolence. Here we describe the pharmacology of novel GABA derivatives(More)
We have studied the effects of various Kampo medicines on P-glycoprotein (P-gp), a drug transporter, in vitro. The present study focused on Daiokanzoto (Da-Huang-Gan-Cao-Tang), which shows the most potent inhibitory effects on P-gp among the 50 Kampo medicines studied, and investigated the P-gp inhibitory effects of Daiokanzoto herbal ingredients (rhubarb(More)
Neuropathic pain is a chronic pain condition resulting from neuronal damage, and is usually treated with pregabalin or gabapentin, which are structurally related to γ-aminobutyric acid (GABA) and are originally developed as anticonvulsant drugs. Here, we report the synthesis and pharmacology of (R)- and (S)-4-amino-3-(trimethylsilyl)methylbutanoic acids (1a(More)