Interleukin-15 stimulates adiponectin secretion by 3T3-L1 adipocytes: Evidence for a skeletal muscle-to-fat signaling pathway
- 作者：LeBris S. Quinn ; Lena Strait-Bodey ; Barbara G. Anderson ; Josep M. Argilé ; s and Peter J. Havel
- 关键词：Interleukin-15 ; Adipocytes ; Skeletal muscle ; Adiponectin ; Cytokines
- 刊名：Cell Biology International
- 出版年：2005
- 期刊代码：164_10656995
- 类别：bio
- 出版时间：2005
- 卷：29
- 期：6
- 页码：449-457
- 文件大小：230 K
摘要
Interleukin-15 (IL-15) is a cytokine which is highly expressed in skeletal muscle tissue, and which has anabolic effects on skeletal muscle protein dynamics both in vivo and in vitro. Additionally, administration of IL-15 to rats and mice inhibits white adipose tissue deposition. To determine if the action of IL-15 on adipose tissue is direct, the capacity of cultured murine 3T3-L1 preadipocytes and adipocytes to respond to IL-15 was examined. IL-15 administration inhibited lipid accumulation in differentiating 3T3-L1 preadipocytes, and stimulated secretion of the adipocyte-specific hormone adiponectin by differentiated 3T3-L1 adipocytes. The latter observation constitutes the first report of a cytokine or growth factor which stimulates adiponectin production. IL-15 mRNA expression by cultured 3T3-L1 adipogenic cells and C2C12 murine skeletal myogenic cells was also examined. Quantitative real-time PCR indicated IL-15 mRNA was expressed by C2C12 skeletal myogenic cells, and was upregulated more than 10-fold in differentiated skeletal myotubes compared to undifferentiated myoblasts. In contrast, 3T3-L1 cells expressed little or no IL-15 mRNA at either the undifferentiated preadipocyte or differentiated adipocyte stages. These findings provide support for the hypothesis that IL-15 functions in a muscle-to-fat endocrine axis which modulates fat:lean body composition and insulin sensitivity.