459 research outputs found

    Stabilization of P/CAF, as a ubiquitin ligase toward MDM2, suppresses mitotic cell death through p53-p21 activation in HCT116 cells with SIRT2 suppression

    Get PDF
    We previously reported that the suppression of SIRT2, an NAD + -dependent protein deacetylases, induces p53 accumulation via degradation of p300 and the subsequent MDM2 degradation, eventually leading to apoptosis in HeLa cells. The present study identified a novel pathway of p53 accumulation by SIRT2 suppression in HCT116(p53+/+) cells in which SIRT2 suppression led to escape from mitotic cell death caused by spindle assembly checkpoint activation induced by microtubule inhibitors such as nocodazole but not apoptosis or G1 or G2 arrest. We found that SIRT2 interacts with P/CAF, a histone acetyltransferase, which also acts as a ubiquitin ligase against MDM2. SIRT2 suppression led to an increase of P/CAF acetylation and its stabilization followed by a decrease in MDM2 and activation of the p53-p21 pathway. Depression of mitotic cell death in HCT116(p53+/+) cells with SIRT2 suppression was released by suppression of P/CAF or p21. Thus, the P/CAF-MDM2-p53-p21 axis enables the escape from mitotic cell death and confers resistance to nocodazole in HCT116(p53+/+) cells with SIRT2 suppression. As SIRT2 has attracted attention as a potential target for cancer therapeutics for p53 regulation, the present study provides a molecular basis for the efficacy of SIRT2 for future cancer therapy based on p53 regulation. These findings also suggest an undesirable function of the SIRT2 suppression associated with activation of the p53-p21 pathway in the suppression of mitotic cell death caused by spindle assembly checkpoint activation

    Bofutsushosan, an Oriental Herbal Medicine, Attenuates the Weight Gain of White Adipose Tissue and the Increased Size of Adipocytes Associated with the Increase in Their Expression of Uncoupling Protein 1 in High-Fat Diet-Fed Male KK/Ta mice

    Get PDF
    Bofutsushosan (BOF), an oriental herbal medicine, has been used as an anti-obesity drug in overweight patients. In the present study, to evaluate the anti-obesity and anti-diabetic effects of BOF, we investigated the effects of BOF on the white adipose tissue (WAT) weight, the size of adipocytes, adiponectin expression, and oral glucose tolerance test results in high-fat diet-fed male KK/Ta mice. In addition, the mRNA expression levels of uncoupling protein 1 (UCP1) and UCP2 mRNA in WAT and brown adipose tissue (BAT) were measured. 6-week-old KK/Ta mice were divided into four groups and fed a purified powdered basal diet (the BD group), a purified high-fat (HF) powdered diet containing suet powder at 37.5 g/100 g diet (the HF group), a high-fat diet plus 1.0% bofutsushosan (BOF) treatment (the HF + BOF group), or a high-fat diet plus 1.0% daisaikoto (DAI) treatment (the HF + DAI group) for 4 weeks. The weight of WAT and the size of adipocytes were increased in the HF group compared with those in the BD group, and these increases in the HF group were significantly inhibited in the HF + BOF group, but not affected in the HF + DAI group. There were no statistically significant differences in plasma levels and tissue mRNA levels of adiponectin among the four groups. There were no significant differences in UCP1 mRNA expression of BAT among the four groups. The expression of UCP1 mRNA in WAT was found in the HF + BOF group, but little expression was seen in the WAT of the BD, HF, or HF + DAI groups. The elevated plasma glucose levels and responses after the glucose loading in the HF group tended to decrease in the HF + BOF group. These results suggest that BOF decreases the weight and size gains of WAT along with up-regulating UCP1 mRNA in WAT in high-fat diet-fed mice

    A Mouse Model of Metabolic Syndrome; Increase in Visceral Adipose Tissue Precedes the Development of Fatty Liver and Insulin Resistance in High-Fat Diet-Fed Male KK/Ta Mice

    Get PDF
    To determine the relative contribution of obesity and visceral white adipose tissue (WAT) to metabolic syndrome, we developed a model that is susceptible to high-fat diet-induced obesity and insulin resistance using male KK/Ta mice. The ratio of WAT weight to body weight was greater in the high-fat diet group compared with the control group in 10-, 14-, and 22-week-old mice. The increase in visceral WAT preceded development of fatty liver and insulin resistance. Adiponectin mRNA expression in WAT was markedly decreased before the decrease in its plasma levels or the development of insulin resistance. Insulin resistance appeared in association with fatty infiltration and TNF-α expression in the liver in 22-week-old mice. These data indicate that our mouse model would be useful for future studies that investigate the role of visceral WAT and its products in the development of metabolic syndrome

    O pensamento de Celso Furtado sobre desenvolvimento econômico e a Abordagem da Complexidade

    Get PDF
    Celso Furtado was an important thinker of economic development in Latin America. However, his ideas have been difficult to measure quantitatively, due to the lack of an economic theory and methodological apparatus able to depict the dynamic, unbalanced, unpredictable, and complex nature of economic development. In the 1980’s, though, complexity economics introduced complex-systems approaches into in economic analysis. In this article, we investigate the possibilities of associating fundamental aspects of Furtado’s structuralist theories, such as core-periphery structures or the need of industrial policies, to complexity thinking in general and the empirical approach of Economic Complexity in particular. We show that Complexity thinking can be linked to Furtado’s historic and structural analysis and allows to advance research on the impact of international trade on global and regional inequality as well as to reveal constraints and opportunities for structural transformation.Celso Furtado foi um importante estudioso da economia latino-americana. Contudo, suas ideias sempre foram difíceis de investigar quantitativamente, devido à inexistência de uma metodologia condizente com o caráter dinâmico, desequilibrado, imprevisível e complexo dos fenômenos econômicos. A Abordagem da Complexidade, introduzida nos anos de 1980, propõe-se a solucionar esse problema, a partir da teoria dos sistemas complexos. Neste artigo investigamos as possibilidades de relacionar a teoria de Furtado com a Abordagem da Complexidade e a forma como os novos métodos empíricos avançam em temas fundamentais ao pensamento estruturalista, como a teoria de centro-periferia e a necessidade de formulação de políticas de desenvolvimento. Observamos que o enfoque da complexidade conecta-se com a análise histórico-estrutural de Furtado e permite aprofundar a investigação sobre as relações de desigualdade e desenvolvimento associadas ao comércio internacional e às limitações e oportunidades de mudança estrutural nas economias

    Transcriptome Analysis for Cytoprotective Actions of Rebamipide against Indomethacin-Induced Gastric Mucosal Injury in Rats

    Get PDF
    We have reported that rebamipide, a gastroprotective drug, suppresses indomethacin-induced gastric mucosal injury in humans and rats. However, the mechanisms of the cytoprotective actions of rebamipide have not been fully addressed. In the present study, we determined mRNA expression profile of the gastric mucosa treated with indomethacin in rats, and investigated the cytoprotective effects of rebamipide against indomethacin-induced injury with a high-density oligonucleotide array (Rat Toxicology U34 GeneChip array). Gastric epithelial cells were obtained by laser-assisted microdissection. Data analysis was performed with a GeneChip Operating Software, GeneSpring software 7.0, and Ingenuity Pathway Analysis. Among 1,031 probes, the expression of 160 probes (15.5%) showed at least 2.0-fold up-regulation (158 probes) and down-regulation (2 probes) 2 h after indomethacin administration in comparison with the vehicle-treated rats. The pathway analysis of the up-regulated 123 probes identified the network with a highly significant score, which consisted of known clusters of cell death, cancer, and endocrine system disorders. We succeeded in listing 10 genes that were up-regulated by the treatment with indomethacin and that were down-regulated by rebamipide, including growth arrest and DNA damage-induced 45α. In conclusion, we demonstrated that cell death, especially apoptosis, pathway is involved in the pathogenesis of indomethacin-induced gastric mucosal injury, and that inhibition of apoptosis-related genes is possibly important for the cytoprotective effect of rebamipide against this injury

    Gastric peroxisome proliferator activator receptor-γ expression and cytoprotective actions of its ligands against ischemia-reperfusion injury in rats

    Get PDF
    The beneficial effects by peroxisome proliferator-activated receptor-γ (PPAR-γ) on gastric injury induced by ischemia-reperfusion have been confirmed, however, the precise mechanism of its cytoprotection is not elucidated thoroughly. The aim of the present study was to determine the gastric localization of PPAR-γ expression in the rat gastric mucosa, and to clarify the mechanism of its cytoprotective properties. The gastric expression of PPAR-γ was confirmed by RT-PCR and western blot, and localized on gastric epithelial cells. The protective effect of PPAR-γ ligands, pioglitazone or 15-deoxy-Δ12,14-prostaglandin J2, on gastric ischemia-reperfusion injury was reversed by the co-administration with PPAR-γ antagonist. The gastric expression of tumor necrosis factor-α and cytokine-induced neutrophil chemoattractant-1 increased significantly in rats treated ischemia-reperfusion, and these increases were significantly inhibited by treatment with pioglitazone. Among the 1,032 probes, 18 probes were up-regulated at least 1.5-fold, 17 were down-regulated at least 1.5-fold by pioglitazone. The network including calnexin, endoplasmic reticulum stress protein, heat shock proteins, and proteasome genes was induced by pioglitazone treatment. In conclusion, activation of gastric epithelial PPAR-γ receptor by its ligands may represent a novel therapeutic approach for gastric inflammation via up-regulation of heat shock proteins and endoplasmic reticulum-related proteins

    Impact of a multidisciplinary rehabilitation nutrition team on evaluating sarcopenia, cachexia and practice of rehabilitation nutrition

    Get PDF
    Background/Aims : To determine whether the presence of a multidisciplinary rehabilitation nutrition team affects sarcopenia and cachexia evaluation and practice of rehabilitation nutrition. Methods : A cross-sectional study using online questionnaire among members of the Japanese Association of Rehabilitation Nutrition (JARN) was conducted. Questions were related to sarcopenia and cachexia evaluation and practice of rehabilitation nutrition. Results : 677 (14.7%) questionnaires were analysed. 44.5% reported that their institution employed a rehabilitation nutrition team, 20.2% conducted rehabilitation nutrition rounds and 26.1% conducted rehabilitation nutrition meetings. A total of 51.7%, 69.7%, 69.0% and 17.8% measured muscle mass, muscle strength, physical function and cachexia, respectively. For those with a rehabilitation nutrition team, 63.5%, 80.7%, 82.4% and 22.9% measured muscle mass, muscle strength, physical function and cachexia, respectively, whereas 46.7%, 78.0% and 78.1% of the respondents reported implementation of nutrition planning strategies in consideration of energy accumulation, rehabilitation training in consideration of nutritional status and use of dietary supplements, respectively. Multivariate logistic regression analysis showed that the use of a rehabilitation nutrition team independently affected sarcopenia evaluation and practice of rehabilitation nutrition but not cachexia evaluation. Conclusions : The presence of a multidisciplinary rehabilitation nutrition team increased the frequency of sarcopenia evaluation and practice of rehabilitation nutrition

    Detection of Nε-(hexanoyl)lysine in the tropomyosin 1 protein in N-methyl-N'-nitro-N-nitrosoguanidine-induced rat gastric cancer cells

    Get PDF
    Nε-(Hexanoyl)lysine, formed by the reaction of lysine with n-6 lipid hydroperoxide, is a lipid peroxidation marker during the initial stage of oxidative stress. The aim of the present study is to indentify Nε-(hexanoyl)lysine-modified proteins in neoplastic transformed gastric mucosal cells by N-methyl-N'-nitro-N-nitrosoguanidine, and to compare the levels of these proteins between gastric mucosal cells and normal gastric cells. Much greater fluorescence of 2-[6-(4'-hydroxy)phenoxyl-3H-xanthen-3-on-9-yl]benzoic acid, an index of the intracellular levels of reactive oxygen species, was observed for gastric mucosal cells compared to normal gastric cells. Nε-(Hexanoyl)lysine-modified proteins were detected by SDS-PAGE or two-dimensional electrophoresis and Western blotting using anti-Nε-(hexanoyl)lysine polyclonal antibody, and a protein band of between 30–40 kDa was clearly increased in gastric mucosal cells compared to normal gastric cells. Two Nε-(hexanoyl)lysine-modified protein spots in gastric mucosal cells were identified as the tropomyosin 1 protein by mass spectrometry using a MASCOT search. The existence of Nε-(hexanoyl)lysine modification in tropomyosin 1 was confirmed by Western blotting of SDS-PAGE-separated or two-dimensional electrophoresis-separated proteins as well as by the immunoprecipitation with anti-tropomyosin 1 antibody. These data indicate that Nε-(hexanoyl)lysine modification of tropomyosin 1 may be related to neoplastic transformation by N-methyl-N'-nitro-N-nitrosoguanidine in gastric epithelial cells
    corecore