Ryuji Hiramatsu

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Fat tissue produces a variety of secreted proteins (adipocytokines) with important roles in metabolism. We isolated a newly identified adipocytokine, visfatin, that is highly enriched in the visceral fat of both humans and mice and whose expression level in plasma increases during the development of obesity. Visfatin corresponds to a protein identified(More)
There is a rapid global rise in obesity, and the link between obesity and diabetes remains somewhat obscure. We identified an adipocytokine, designated as visceral adipose tissue-derived serpin (vaspin), which is a member of serine protease inhibitor family. Vaspin cDNA was isolated by from visceral white adipose tissues (WATs) of Otsuka Long-Evans(More)
While searching for natural ligands for the peroxisome proliferator-activated receptor (PPAR) gamma, we identified a synthetic compound that binds to this receptor. Bisphenol A diglycidyl ether (BADGE) is a ligand for PPARgamma with a K(d(app)) of 100 microM. This compound has no apparent ability to activate the transcriptional activity of PPARgamma;(More)
Krüppel-like zinc finger transcription factors (KLFs) play diverse roles during cell differentiation and development in mammals. We have now shown by microarray analysis that expression of the KLF15 gene is markedly up-regulated during the differentiation of 3T3-L1 preadipocytes into adipocytes. Inhibition of the function of KLF15, either by expression of a(More)
In mammals, male sex is determined by the Y-chromosomal gene Sry (sex-determining region of Y chromosome). The expression of Sry and subsequently Sox9 (SRY box containing gene 9) in precursors of the supporting cell lineage results in the differentiation of these cells into Sertoli cells. Sertoli cells in turn orchestrate the development of all other(More)
PKClambda is implicated as a downstream effector of PI3K in insulin action. We show here that mice that lack PKClambda specifically in the liver (L-lambdaKO mice), produced with the use of the Cre-loxP system, exhibit increased insulin sensitivity as well as a decreased triglyceride content and reduced expression of the sterol regulatory element-binding(More)
The transcription factor, signal transducer and activator of transcription-3 (STAT-3) contributes to various physiological processes. Here we show that mice with liver-specific deficiency in STAT-3, achieved using the Cre-loxP system, show insulin resistance associated with increased hepatic expression of gluconeogenic genes. Restoration of hepatic STAT-3(More)
White adipocytes are unique in that they contain large unilocular lipid droplets that occupy most of the cytoplasm. To identify genes involved in the maintenance of mature adipocytes, we expressed dominant-negative PPARgamma in 3T3-L1 cells and performed a microarray screen. The fat-specific protein of 27 kDa (FSP27) was strongly downregulated in this(More)
In mammals, the Y-linked sex-determining gene Sry cell-autonomously promotes Sertoli cell differentiation from bipotential supporting cell precursors through SRY-box containing gene 9 (Sox9), leading to testis formation. Without Sry action, the supporting cells differentiate into granulosa cells, resulting in ovarian development. However, how Sry acts(More)
STAT3 regulates glucose homeostasis by suppressing the expression of gluconeogenic genes in the liver. The mechanism by which hepatic STAT3 is regulated by nutritional or hormonal status has remained unknown, however. Here, we show that an increase in the plasma insulin concentration, achieved either by glucose administration or by intravenous insulin(More)