Hitoshi Ashida

Kobe University, Kōbe, Hyōgo, Japan

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Publications (160)333.11 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: It is well known that tea has a variety of beneficial impacts on human health, including anti-obesity effects. It is well documented that green tea and its constituent catechins suppress obesity, but the effects of other tea on obesity and its potential mechanisms involved are not yet fully understood. In this study, we investigated suppression of adiposity by oolong, black and pu-erh tea and characterized the underlying molecular mechanism in vivo. We found that consumption of oolong, black or pu-erh tea for a period of one week significantly decreased visceral fat without affecting body weight in male ICR mice. On a mechanistic level, consumption of tea increased phosphorylation of AMP-activated protein kinase (AMPK) in white adipose tissue (WAT). This was accompanied by the induction of WAT protein levels of uncoupling protein 1 and insulin-like growth factor binding protein 1. Our results indicate that oolong, black and pu-erh tea, in particular black tea, suppresses adiposity via phosphorylation of the key metabolic regulator AMPK and increases browning of WATs.
    Food Funct. 07/2014;
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    ABSTRACT: Thioredoxin (TRX) is a redox regulating protein which has protective effects against oxidative stress-induced damage to cells and tissues. In this study, we investigated the effects of orally administered TRX derived from edible yeast, Saccharomyces cerevisiae, on gastric mucosa. First, we examined the digestibility of orally administered yeast TRX in mice, and detected yeast TRX in the stomach for 4 h after administration. Next, we investigated the mitigation of gastric mucosal injury after the oral administration of yeast TRX in water-immersion restraint stress and HCl/ethanol-induced gastric ulcer models. Furthermore, we conducted DNA microarray analysis, using the HCl/ethanol-induced model, which revealed that several groups of genes related to tissue repair were upregulated in ulcer regions in the stomachs of rats administered with yeast TRX. These results demonstrated the viability of the use of oral administrations of yeast TRX to protect the gastric mucosa.
    Bioscience Biotechnology and Biochemistry 07/2014; 78(7):1221-1230. · 1.27 Impact Factor
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    ABSTRACT: The present study demonstrates that glabridin, a prenylated isoflavone in licorice, stimulates glucose uptake through the adenosine monophosphate-activated protein kinase (AMPK) pathway in L6 myotubes. Treatment with glabridin for 4 h induced glucose uptake in a dose-dependent manner accompanied by the translocation of glucose transporter type 4 (GLUT4) to the plasma membrane. Glabridin needed at least 4 h to increase glucose uptake, while it significantly decreased glycogen and increased lactic acid within 15 min. Pharmacological inhibition of AMPK by compound C suppressed the glabridin-induced glucose uptake, whereas phosphoinositide 3-kinase and Akt inhibition by LY294002 and Akt1/2 inhibitor, respectively, did not. Furthermore, glabridin induced AMPK phosphorylation, and siRNA for AMPK completely abolished glabridin-induced glucose uptake. We confirmed that glabridin-rich licorice extract prevent glucose intolerance accompanied by the AMPK-dependent GLUT4 translocation in the plasma membrane of skeletal muscle. These results indicate that glabridin may possess a therapeutic effect on metabolic disorders, such as diabetes and hyperglycemia, by modulating glucose metabolism through AMPK in skeletal muscle cells.
    Molecular and Cellular Endocrinology 06/2014; · 4.04 Impact Factor
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    ABSTRACT: Drugs, xenobiotics including environmental pollutants, and certain food components modulate expression of drug-metabolizing enzymes. An aryl hydrocarbon receptor (AhR) possesses possible expression of phase I and phase II enzymes directly by binding of its ligands such as 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and indirectly by regulating expression of nuclear factor-erythroid-2-related factor 2 (Nrf2). Previous our result demonstrated that lueolin, a natural flavonoid existing in vegetables and herbs, competed the binding of TCDD to AhR. In the present study, we investigated the effect of luteolin on the expression of drug-metabolizing enzymes through the AhR and Nrf2 pathways. Luteolin inhibited TCDD-induced protein expression of phase I enzyme cytochrome P450 1A1 (CYP1A1), phase II enzymes NAD(P)H:quinone oxidoreductase-1 (NQO1) and glutathione-S-transferase P1 (GSTP1) in HepG2, Hepa1c1c7 and RL-34 cells in a dose-dependent manner. Luteolin suppressed TCDD- and tert-butylhydroquinone induced Nrf2 protein by decreasing its stability in HepG2 cells. In tert-butylhydroquinone treated cells, luteolin dose-dependently inhibited NQO1, GSTP1 and aldo-keto reductases (AKRs). Of these, protein expression of CYP1A1 and GSTP1 was mainly dominated by the AhR pathway, while that of NQO1 and AKRs was by the Nrf2 pathway. In conclusion, luteolin inhibits expression of phase I and phase II drug-metabolizing enzymes by modulating the AhR and Nrf2 pathways.
    Archives of Biochemistry and Biophysics 06/2014; · 3.37 Impact Factor
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    ABSTRACT: We searched for polyphenols capable of inhibiting the lipid accumulation in 3T3-L1 cells, and investigated the mechanisms of two effective chalcones cardamonin and flavokawain B on differentiation of preadipocytes.
    Archives of Biochemistry and Biophysics 05/2014; · 3.37 Impact Factor
  • Tianshun Zhang, Norio Yamamoto, Hitoshi Ashida
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    ABSTRACT: Excessive lipid accumulation in the liver has been proposed to cause hyperlipidemia, diabetes and fatty liver disease. 4-Hydroxyderricin (4HD), xanthoangelol (XAG), cardamonin (CAR) and flavokawain B (FKB) are chalcones that have exhibited various biological effects against obesity, inflammation, and diabetes; however, little is known about the inhibitory effects of these chalcones on fatty liver disease. In the present study, we investigated the ability of 4HD, XAG, CAR, and FKB to reduce lipid accumulation in hepatocytes. When HepG2 cells were treated with a mixture of fatty acids (FAs; palmitic acid : oleic acid = 1 : 2 ratio), significant lipid accumulation was observed. Under the same experimental conditions, addition of chalcones at 5 μM significantly suppressed the FA-induced lipid accumulation. We found that the expression of sterol regulatory element-binding protein-1 (SREBP-1), a key molecule involved in lipogenesis, was decreased in these chalcone-treated cells. We also found that these chalcones increased the expression of peroxisome proliferator-activated receptor α (PPARα), which is involved in FA oxidation. Moreover, these chalcones increased phosphorylation of AMP-activated protein kinase (AMPK) and liver kinase B1 (LKB1), upstream regulators of SREBP-1 and PPARα. We confirmed that an AMPK inhibitor, compound C, reversed chalcone-induced changes in SREBP-1 and PPARα expression in the HepG2 cells. Collectively, we found that 4HD, XAG, CAR, and XAG attenuated lipid accumulation through activation of the LKB1/AMPK signaling pathway in HepG2 cells.
    Food & function. 04/2014;
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    ABSTRACT: Although the underlying mechanism is unclear, β-conglycinin (βCG), the major component of soy proteins, regulates blood glucose levels. Here, we hypothesized that consumption of βCG would normalize blood glucose levels by ameliorating insulin resistance and stimulating glucose uptake in skeletal muscles. To test our hypothesis, we investigated the antidiabetic action of βCG in spontaneously diabetic Goto-Kakizaki (GK) rats. Our results revealed that plasma adiponectin levels and adiponectin receptor 1 messenger RNA expression in skeletal muscle were higher in βCG-fed rats than in casein-fed rats. Phosphorylation of adenosine monophosphate-activated protein kinase (AMP kinase) but not phosphatidylinositol-3 kinase was activated in βCG-fed GK rats. Subsequently, βCG increased translocation of glucose transporter 4 to the plasma membrane. Unlike the results in skeletal muscle, the increase in adiponectin receptor 1 did not lead to AMP kinase activation in the liver of βCG-fed rats. The down-regulation of sterol regulatory element-binding factor 1, which is induced by low insulin levels, promoted the increase in hepatic insulin receptor substrate 2 expression. Based on these findings, we concluded that consumption of soy βCG improves glucose uptake in skeletal muscle via AMP kinase activation and ameliorates hepatic insulin resistance and that these actions may help normalize blood glucose levels in GK rats.
    Nutrition research 02/2014; 34(2):160-7. · 2.59 Impact Factor
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    ABSTRACT: The Japanese herb, Ashitaba (Angelica keiskei Koidzumi), contains two prenylated chalcones, 4-hydroxyderricin and xanthoangelol, which are considered to be the major active compounds of Ashitaba. However, their effects on inflammatory responses are poorly understood. In the present study, we investigated the effects and underlying molecular mechanisms of 4-hydroxyderricin and xanthoangelol on lipopolysaccharide (LPS)-induced inflammatory responses in RAW264 mouse macrophages. LPS-mediated production of nitric oxide (NO) was markedly reduced by 4-hydroxyderricin (10 μM) and xanthoangelol (5 μM) compared with their parent compound, chalcone (25 μM). They also inhibited LPS-induced secretion of tumor necrosis factor-alpha (TNF-α), and gene and protein expression of inducible NO synthase (iNOS) and cyclooxygenase-2 (COX-2). Although chalcone decreased the DNA-binding activity of both activator protein-1 (AP-1) and nuclear factor-kappa B (NF-κB), 4-hydroxyderricin and xanthoangelol suppressed only AP-1 and had no effect on NF-κB. On the other hand, all of the tested chalcones reduced the phosphorylation (at serine 536) level of the p65 subunit of NF-κB. 4-Hydroxyderricin and xanthoangelol may be promising for the prevention of inflammatory diseases.
    Journal of Agricultural and Food Chemistry 12/2013; · 3.11 Impact Factor
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    ABSTRACT: Based on a recent study indicating that enzymatically synthesized glycogen (ESG) possesses a dietary, fiber-like action, we hypothesized that ESG can reduce the risk of obesity. In this study, the antiobesity effects of ESG were investigated in a model of diet-induced obesity. Male Sprague-Dawley rats were divided into 4 groups and fed a normal or high-fat diet, with or without 20% ESG, for 4 weeks. Body weight, food intake, lipid deposition in the white adipose tissues and liver, fecal lipid excretion, and plasma lipid profiles were measured. At week 3, the body fat mass was measured using an x-ray computed tomography system, which showed that ESG significantly suppressed the high-fat diet-induced lipid accumulation. Similar results were observed in the weight of the adipose tissue after the experiment. Moreover, ESG significantly suppressed the lipid accumulation in the liver but increased fecal lipid excretion. The plasma concentrations of triacylglycerol and nonesterified fatty acid were lowered after a high-fat diet, whereas the total bile acid concentration was increased by ESG. However, the hepatic messenger RNA (mRNA) levels of enzymes related to lipid metabolism were not affected by ESG. Conversely, the mRNA levels of long-chain acyl-CoA dehydrogenase and medium-chain acyl-CoA dehydrogenase were up-regulated by ESG in the muscle. These results suggest that the combined effects of increased fecal lipid excretion, increased mRNA levels of enzymes that oxidize fatty acids in the muscle, and increased total bile acid concentration in the plasma mediate the inhibitory effect of ESG on lipid accumulation.
    Nutrition research 09/2013; 33(9):743-52. · 2.59 Impact Factor
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    ABSTRACT: Previously, we developed enzymatically synthesized glycogen (ESG) from starch, and showed its immunomodulatory and dietary fiber-like activities. In this study, we investigated the metabolism of ESG and its immunomodulatory activity using differentiated Caco-2 cells as a model of the intestinal barrier. In a co-culture system consisting of differentiated Caco-2 cells and RAW264.7 macrophages, mRNA expression of IL-6, IL-8, IL-1β and BAFF cytokines was up-regulated in Caco-2 cells and IL-8 production in basolateral medium was induced after 24 h apical treatment with 5 mg ml(-1) of ESG. The mRNA level of iNOS was also up-regulated in RAW264.7 macrophages. After characterization of the binding of anti-glycogen monoclonal antibodies (IV58B6 and ESG1A9) to ESG and its digested metabolite resistant glycogen (RG), an enzyme-linked immunosorbent assay (ELISA) system was developed to quantify ESG and RG. Using this system, we investigated the metabolism of ESG in differentiated Caco-2 cells. When ESG (7000 kDa, 5 mg ml(-1)) was added to the apical side of Caco-2 monolayers, ESG disappeared and RG (about 3000 kDa, 3.5 mg ml(-1)) appeared in the apical solution during a 24 h incubation. Neither ESG nor RG was detected in the basolateral solution. In addition, both ESG and RG were bound to TLR2 in Caco-2 cells. In conclusion, we suggest that ESG is metabolized to a RG-like structure in the intestine, and this metabolite activates the immune system via stimulation of the intestinal epithelium, although neither ESG nor its metabolite could permeate the intestinal cells under our experimental conditions. These results provide evidence for the beneficial function of ESG as a food ingredient.
    Food & function. 07/2013;
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    ABSTRACT: SCOPE: 10-Hydroxy-2-decenoic acid (10H2DA) is one of the unique medium-chain fatty acids (MCFAs) specifically found in royal jelly. We hypothesize that 10H2DA has multiple biological functions and may aid in 5'-AMP-activated protein kinase (AMPK) activation and affect the glucose transport system in skeletal muscle. METHODS AND RESULTS: We examined whether various MCFAs present in royal jelly activated AMPKα. Treatment of L6 myotubes with various MCFAs showed that 10H2DA administration resulted in a significant increase in phosphorylated AMPKα. 10H2DA activates AMPK independently of insulin and significantly increased glucose uptake into L6 myotubes following translocation of glucose transporter 4 (Glut4) to the plasma membrane (PM). The activation was induced by the upstream kinase Ca(2+) /calmodulin-dependent kinase kinase β, but was independent of changes in AMP:ATP ratio and the liver kinase B1 pathway. Oral administration of 10H2DA significantly stimulated phosphorylation of AMPK and Glut4 translocation to the PM in mouse skeletal muscle. CONCLUSION: These findings indicate that (i) 10H2DA activates AMPK, and insulin independently enhances glucose uptake following translocation of Glut4 to PM, (ii) activation of AMPKα by 10H2DA is mediated via extracellular Ca(2+) -dependent Ca(2+) /calmodulin-dependent kinase kinase β, without alteration in the AMP:ATP ratio, and liver kinase B1 was not involved in the activation.
    Molecular Nutrition & Food Research 06/2013; · 4.31 Impact Factor
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    ABSTRACT: Black soybean seed coat has abundant levels of polyphenols such as anthocyanins (cyanidin 3-glucoside; C3G) and procyanidins (PCs). In this study, we found that dietary black soybean seed coat extract (BE) ameliorates hyperglycemia and insulin sensitivity via the activation of AMP-activated protein kinase (AMPK) in type 2 diabetic mice. Dietary BE significantly reduced blood glucose levels and enhanced insulin sensitivity. AMPK was activated in the skeletal muscle and liver of diabetic mice fed BE. This activation was accompanied by the upregulation of glucose transporter 4 in skeletal muscle and the downregulation of gluconeogenesis in the liver. These changes resulted in improved hyperglycemia and insulin sensitivity in type 2 diabetic mice. In vitro studies using L6 myotubes showed that C3G and PCs significantly induced AMPK activation and enhanced glucose uptake into the cells.
    Journal of Agricultural and Food Chemistry 05/2013; · 3.11 Impact Factor
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    ABSTRACT: SCOPE: Adipocytes differentiation is deeply involved in the onset of obesity. 4-Hydroxyderricin (4HD) and xanthoangelol (XAG) are the chalcones that are derived from Ashitaba (Angelica keiskei). In this study, we demonstrated the inhibitory effects of these chalcones on adipocytes differentiation. METHODS AND RESULTS: 4HD and XAG suppressed intracellular lipid accumulation by Oil red O staining at 5 μM without cytotoxicity. They inhibited adipocytes differentiation accompanied by down-expression of adipocyte-specific transcription factors, CCAAT/enhancer-binding protein-β (C/EBP-β), C/EBP-α, and peroxisome proliferator-activated receptor gamma (PPAR-γ) using RT-PCR and Western blotting analysis. To obtain insights into the underlying mechanism, the activation of AMP-activated protein kinase (AMPK) and mitogen-activated protein kinase pathways was investigated. These two chalcones promoted phosphorylation of AMPK and acetyl CoA carboxylase during differentiation of 3T3-L1 adipocytes accompanied by a decrease in glycerol-3-phosphate acyl transferase-1 and an increase in carnitine palmitoyltransferase-1 mRNA expression. These chalcones also promoted phosphorylation of extracellular signal-regulated kinases and Jun aminoterminal kinases, but not p38. Moreover, the inhibitors for AMPK and extracellular signal-regulated kinases abolished the chalcones-caused down-expression of C/EBP-β, C/EBP-α, and PPAR-γ. Treatment with Jun aminoterminal kinases inhibitor abolished the down-expression of C/EBP-α and PPAR-γ, but not C/EBP-β. CONCLUSION: 4HD and XAG inhibit adipocytes differentiation through AMPK and mitogen-activated protein kinase pathways, resulting in the down-expression of adipocyte-specific transcription factors.
    Molecular Nutrition & Food Research 05/2013; · 4.31 Impact Factor
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    ABSTRACT: Simple pharmacological studies on inositol stereoisomers are presented in this study. Male ICR mice were orally administered 1 g/kg BW of three inositol stereoisomers, myo-inositol (MI), D-chiro-inositol (DCI), and scyllo-inositol (SI), and blood plasma samples and skeletal muscle fractions were prepared after an hour. The plasma samples were subjected to gas chromatography-coupled time-of-flight mass spectrometry (GC-TOF-MS) analysis. None of the three stereoisomers was seen in untreated samples, but substantial amounts ranging from 2.5 to 6.5 mM were detected only after administration, indicating that orally administered inositol stereoisomers were readily absorbed and their levels elevated in the bloodstream. In addition, plasma of SI-administered animals contained substantial MI, suggesting a possible metabolic conversion of SI to MI. In the skeletal muscle fractions, glucose transporter type 4 (GLUT4) content in the plasma membrane tended to increase, implying that the three inositol stereoisomers stimulated GLUT4 translocation.
    Journal of Agricultural and Food Chemistry 05/2013; · 3.11 Impact Factor
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    ABSTRACT: Procyanidins are oligomers and polymers of flavan-3-ols consisting of (-)-epicatechin subunits. In this study, we isolated and purified dimeric, trimeric and tetrameric procyanidins from cacao liquor and investigated their influence on the "incretin effect" as compared to the monomer, (-)-epicatechin in mice. Cinnamtannin A2 specifically increased the glucagon-like peptide-1 (GLP-1) and insulin secretion levels in the plasma after 60 min administration. As evidence of the action of insulin, activation of insulin receptor and insulin receptor substrate-1 was observed in the soleus muscle. These results indicate that the intake of cinnamtannin A2 may improve hyperglycemia through an incretin-like effect, accompanied by activation of the insulin-signaling pathway.
    Bioscience Biotechnology and Biochemistry 04/2013; · 1.27 Impact Factor
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    ABSTRACT: Black soybean seed coat is a rich source of polyphenols that have been reported to have various physiological functions. The present study investigated the potential protective effects of polyphenolic extracts from black soybean seed coat on DNA damage in human hepatoma HepG2 cells and ICR mice. The results from micronucleus (MN) assay revealed that black soybean seed coat extract (BE) at concentrations up to 25μg/mL was non-genotoxic. It is noteworthy that BE (at 4.85μg/mL) and its main components, procyanidins (PCs) and cyanidin 3-glucoside (C3G), at 10μM significantly reduced the genotoxic effect induced by benzo[a]pyrene [B(a)P]. To obtain insights into the underlying mechanism, we investigated BE and its main components on drug-metabolizing enzyme expression. The results of this study demonstrate that BE and its main components, PCs and C3G, down-regulated B(a)P-induced cytochrome P4501A1 (CYP1A1) expression by inhibiting the transformation of aryl hydrocarbon receptor. Moreover, they increased expression of detoxifying defense enzymes, glutathione S-transferases (GSTs) via increasing the binding of nuclear factor-erythroid-2-related factor 2 to antioxidant response elements. Collectively, we found that PCs and C3G, which are the main active compounds of BE, down-regulated CYP1A1 and up-regulated GST expression to protect B(a)P-induced DNA damage in HepG2 cells and ICR mice effectively.
    Mutation Research/Fundamental and Molecular Mechanisms of Mutagenesis 01/2013; · 3.90 Impact Factor
  • Manabu Ueda, Kaori Hayashibara, Hitoshi Ashida
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    ABSTRACT: It is well known that propolis has the ability to prevent hyperglycemia. However, the underlying mechanism is not yet fully understood. We therefore investigated whether a Brazilian propolis ethanol extract affects glucose uptake and translocation of insulin-sensitive glucose transporter (GLUT) 4 in skeletal muscle cells. In L6 myotubes, the extract at 1 μg/mL significantly promoted GLUT4 translocation and glucose uptake activity. Regarding the mechanism of GLUT4 translocation, propolis extract induced both PI3K and AMPK phosphorylation in a dose-dependent manner in L6 myotubes. However, we could not define which pathway was preferentially associated with GLUT4 translocation, because both PI3K and AMPK inhibitors revealed off-target effects to each other. The main polyphenols found in the propolis extract, artepillin C, coumaric acid, and kaempferide, promoted GLUT4 translocation in L6 myotubes. Additionally, these compounds activated both PI3K- and AMPK-dependent dual-signaling pathways. However, only kaempferide increased glucose uptake activity under our experimental conditions. Single oral administrations of propolis extract, at 250 mg/kg body weight, lowered postprandial blood glucose levels in ICR mice. The extract promoted GLUT4 translocation in skeletal muscle of rats and mice, but did not inhibit α-glucosidase activity in the small intestine under our experimental conditions. It was confirmed that propolis extract promoted phosphorylation of both PI3K and AMPK in rat skeletal muscle. In conclusion, we show that Brazilian propolis has the potential to prevent hyperglycemia through the promotion of GLUT4 translocation in skeletal muscle and that kaempferide is one of the candidates for active compound in propolis. © 2013 BioFactors, 2013.
    BioFactors 01/2013; · 3.09 Impact Factor
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    ABSTRACT: Hyperglycaemia and insulin resistance are associated with the increased risk of the metabolic syndrome and other severe health problems. The insulin-sensitive GLUT4 regulates glucose homoeostasis in skeletal muscle and adipose tissue. In this study, we investigated whether cacao liquor procyanidin (CLPr) extract, which contains epicatechin, catechin and other procyanidins, improves glucose tolerance by promoting GLUT4 translocation and enhances glucose uptake in muscle cells. Our results demonstrated that CLPr increased glucose uptake in a dose-dependent manner and promoted GLUT4 translocation to the plasma membrane of L6 myotubes. Oral administration of a single dose of CLPr suppressed the hyperglycaemic response after carbohydrate ingestion, which was accompanied by enhanced GLUT4 translocation in ICR mice. These effects of CLPr were independent of α-glucosidase inhibition in the small intestine. CLPr also promoted GLUT4 translocation in skeletal muscle of C57BL/6 mice fed a CLPr-supplemented diet for 7 d. These results indicate that CLPr is a beneficial food material for improvement of glucose tolerance by promoting GLUT4 translocation to the plasma membrane of skeletal muscle.
    Journal of Nutritional Science. 11/2012; 1.
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    ABSTRACT: The anti-hyperglycemic effects of tea are well documented. However, the effects of fermented tea on the translocation of glucose transporter 4 (GLUT4), the major glucose transporter for glucose uptake in the postprandial period, in skeletal muscle and the underlying molecular mechanisms are not fully understood. In this study, we investigated the translocation of GLUT4 and its related signaling pathways in skeletal muscle of male ICR mice given fermented tea. Intake of oolong, black, or pu-erh tea for 7 days enhanced GLUT4 translocation to the plasma membrane of skeletal muscle. Each type of fermented tea stimulated the phosphorylation of phosphoinositide 3-kinase (PI3K), Akt/protein kinase B, and AMP-activated protein kinase (AMPK). Fermented tea also increased the protein expression of insulin receptor. These results strongly suggest that fermented tea activates both PI3K/Akt- and AMPK-dependent signaling pathways to induce GLUT4 translocation, and increases the expression of insulin receptor to improve glucose intolerance.
    Journal of Agricultural and Food Chemistry 10/2012; · 3.11 Impact Factor
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    ABSTRACT: Grape pomace is generated in the production process of wine and grape juices and is an industrial waste. This study investigated whether an intake of grape pomace was able to suppress chronic inflammation induced by lipopolysaccharide (LPS) and galactosamine (GalN) in vivo. When Sprague-Dawley rats were orally given methanolic extracts from red and white grape pomace, the extracts inhibited the LPS/GalN-evoked activation of nuclear factor-κB (NF-κB) dose-dependently, and red grape pomace exerted a stronger effect than white grape one. Next, rats were fed an AIN93 M-based diet containing 5% red grape pomace for 7 days, followed by the intraperitoneal injection of LPS and GalN. The intake of the red grape pomace-supplemented diet was found to suppress the LPS/GalN-induced activation of NF-κB and expression of inducible nitric oxide synthase and cyclooxygenase-2 proteins. These results suggest that red grape pomace may contain an abundance of effective compound(s) for anti-inflammatory action.
    Journal of Agricultural and Food Chemistry 08/2012; 60(36):9315-20. · 3.11 Impact Factor

Publication Stats

2k Citations
333.11 Total Impact Points

Institutions

  • 1970–2014
    • Kobe University
      • • Department of Agrobioscience
      • • Graduate School of Agricultural Science
      • • Department of Biofunctional Chemistry
      Kōbe, Hyōgo, Japan
  • 2011–2013
    • Ezaki Glico Co., Ltd.
      Ōsaka, Ōsaka, Japan
  • 2008–2013
    • Chubu University
      • College of Bioscience and Biotechnology
      Kasugai, Aichi-ken, Japan
  • 2011–2012
    • Wuhan University
      • Department of Chemistry
      Wuhan, Hubei, China
  • 2006–2010
    • The University of Tokyo
      • Department of Applied Biological Chemistry
      Tokyo, Tokyo-to, Japan
  • 2009
    • University of Shizuoka
      • Institute for Environmental Sciences
      Shizuoka-shi, Shizuoka-ken, Japan