The University of Osaka · 의학
히토시 시즈와 교수가 이끄는 연구실은 대사질환, 특히 비만, 인슐린 저항성, 간지방간 및 간섬유화와 관련된 생물학적 메커니즘을 중심으로 연구를 진행하고 있습니다. 지방세포에서 분비되는 혈액형성 단백질(adiponectin)과 같은 대사조절 단백질, 그리고 근육에서 분비되는 신규 신호단백질(musclin)과 같은 새로운 생체 활성 인자들의 기능을 규명하며, 호르몬(성호르몬, GH, IGF-I)과 핵수용체(SHP)가 대사 및 간질환에 미치는 영향을 탐구하고 있습니다. 특히 대사 혼란과 관련된 산화 스트레스, 염증, 세포 노화 등과의 상호작용 메커니즘을 중심으로 기초-임상 연계 연구를 수행하고 있습니다.
표시된 성과는 수집된 데이터 기준으로 산출되며, 일부 차이가 있을 수 있습니다.
Adiponectin, an adipose-specific secretory protein, exhibits antidiabetic and antiatherogenic properties. In the present study, we examined the effects of sex hormones on the regulation of adiponectin production. Plasma adiponectin concentrations were significantly lower in 442 men (age, 52.6 +/- 11.9 years [mean +/- SD]) than in 137 women (53.2 +/- 12.0 years) but not different between pre- and postmenopausal women. In mice, ovariectomy did not alter plasma adiponectin levels. In contrast, high
Obesity is often accompanied by hyperuricemia. However, purine metabolism in various tissues, especially regarding uric acid production, has not been fully elucidated. Here we report, using mouse models, that adipose tissue could produce and secrete uric acid through xanthine oxidoreductase (XOR) and that the production was enhanced in obesity. Plasma uric acid was elevated in obese mice and attenuated by administration of the XOR inhibitor febuxostat. Adipose tissue was one of major organs that
Adult hypopituitary patients with GHD demonstrated a high NAFLD prevalence. The effect of GH replacement therapy suggests that the NAFLD is predominantly attributable to GHD.
Skeletal muscle is involved in the homeostasis of glucose and lipid metabolism. We hypothesized that the skeletal muscle produces and secretes bioactive factor(s), similar to adipocytokines secreted by fat tissue. Here, we report the identification of a novel secretory factor, musclin, by signal sequence trap of mouse skeletal muscle cDNAs. Musclin cDNA encoded 130 amino acids, including NH(2)-terminal 30-amino acid signal sequence. Musclin protein contained a region homologous to natriuretic pe
Hepatic fibrosis in nonalcoholic steatohepatitis (NASH) and cirrhosis determines patient prognosis; however, effective treatment for fibrosis has not been established. Oxidative stress and inflammation activate hepatic stellate cells (HSCs) and promote fibrosis. In contrast, cellular senescence inhibits HSCs' activity and limits fibrosis. The aim of this study was to explore the effect of IGF-I on NASH and cirrhotic models and to clarify the underlying mechanisms. We demonstrate that IGF-I signi
Small heterodimer partner (SHP, NR0B2) is an atypical orphan nuclear receptor that inhibits transcriptional activation by several other nuclear receptors. We recently reported that mutations in the SHP gene are associated with insulin resistance. In the present study, we demonstrated that the SHP gene is expressed in adipose tissues. A reporter gene assay showed that a gene product of SHP increased the transcriptional activation of peroxisome proliferator-activated receptor (PPAR) gamma. SHP-med
Objective The production of uric acid in murine white adipose tissue (mWAT), and that such production was augmented in obese mice, was recently reported. However, little is known about the secretion of metabolites associated with purine catabolism in human WAT (hWAT). The present study analyzed this in hWAT. Methods Freshly isolated hWAT and mWAT were cultured. The secretion of metabolites associated with purine catabolism was measured. Tissue distribution profiles of genes associated with purin
