TY - JOUR
T1 - Pituitary growth hormone suppression reduces resistin expression and enhances insulin effectiveness
T2 - Relationship with caloric restriction
AU - Chiba, Takuya
AU - Yamaza, Haruyoshi
AU - Komatsu, Toshimitsu
AU - Nakayama, Masahiko
AU - Fujita, Satoshi
AU - Hayashi, Hiroko
AU - Higami, Yoshikazu
AU - Shimokawa, Isao
N1 - Funding Information:
We are grateful to the staff of the Biomedical Research Center at the Center for Frontier Life Sciences, Nagasaki University, for their technical assistance and animal care. We also thank Yutaka Araki and Yuko Moriyama for technical assistance. This work was supported in part by a Grant-in-Aid for Science Research from the Japan Society for the Promotion of Science (No. 15390128).
PY - 2008/6
Y1 - 2008/6
N2 - Caloric restriction (CR) retards various age-dependent disorders, increases lifespan, and improves insulin activity in laboratory animals. Recently, adipocytes were found to act together as an active endocrine organ that produces various hormones called adipocytokines. The peripheral and central activities of these adipocytokines have been suggested to mediate the anti-aging effects of CR. Here, we tested this notion by analyzing the effect of CR and suppression of growth hormone/insulin-like growth factor-I (GH/IGF-I) axis on the expression of resistin, adiponectin, and adipsin genes by rat white adipose tissue (WAT). We found that CR and GH/IGF-I suppression markedly downregulated resistin gene expression. We also found plasma resistin levels correlated positively with pituitary GH mRNA expression levels. Our observations suggest that CR reduces resistin expression and increases insulin effectiveness in a GH/IGF-I-dependent manner. The beneficial effects of CR and GH/IGF-I suppression appear to be mediated, at least in part, by changes in glucose metabolism that result from reductions in plasma resistin levels.
AB - Caloric restriction (CR) retards various age-dependent disorders, increases lifespan, and improves insulin activity in laboratory animals. Recently, adipocytes were found to act together as an active endocrine organ that produces various hormones called adipocytokines. The peripheral and central activities of these adipocytokines have been suggested to mediate the anti-aging effects of CR. Here, we tested this notion by analyzing the effect of CR and suppression of growth hormone/insulin-like growth factor-I (GH/IGF-I) axis on the expression of resistin, adiponectin, and adipsin genes by rat white adipose tissue (WAT). We found that CR and GH/IGF-I suppression markedly downregulated resistin gene expression. We also found plasma resistin levels correlated positively with pituitary GH mRNA expression levels. Our observations suggest that CR reduces resistin expression and increases insulin effectiveness in a GH/IGF-I-dependent manner. The beneficial effects of CR and GH/IGF-I suppression appear to be mediated, at least in part, by changes in glucose metabolism that result from reductions in plasma resistin levels.
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U2 - 10.1016/j.exger.2008.03.003
DO - 10.1016/j.exger.2008.03.003
M3 - Article
C2 - 18430535
AN - SCOPUS:43649098702
SN - 0531-5565
VL - 43
SP - 595
EP - 600
JO - Experimental Gerontology
JF - Experimental Gerontology
IS - 6
ER -