Submitted to: Adipocytes
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/1/2006
Publication Date: 3/28/2006
Citation: Poulos, S.P., Hausman, G.J. 2006. Adipogenesis in stromal-vascular cell cultures derived from fetal semitendinosus muscle and subcutaneous adipose tissue. Adipocytes. 2:29-36.
Interpretive Summary: Thiazolidinediones are drugs that are used to treat type 2 diabetes. The thiazolidinedione used in this study was troglitazone. This study shows that thiazolidinediones can induce development of new fat cells from fat tissue and skeletal muscle precursor cells from very young fetuses. Troglitazone stimulates much more fat cell development in fat tissue and muscle precursor cell cultures than does glucocorticoids. Regardless of troglitazone, muscle cells and fat cells developed in fetal cultures of skeletal muscle precursor cells. This suggests that the development of fat cells in skeletal muscle or marbling fat cells could be precociously induced with troglitazone.
Technical Abstract: This study was undertaken to determine if intramuscular adipocytes are present, and can be recruited, in semitendinosus muscle (STM) stromal-vascular (S-V) cells from 105, 90, and 75 d fetal pigs. Stromal- vascular cells from STM and subcutaneous adipose (SQ) tissues were isolated using a collagenase digestion. One h after plating in 10% fetal bovine serum (FBS), cells were treated with fresh media containing FBS, FBS+dexamethasone (FBS + Dex), FBS+DMSO, FBS+ 10 'M troglitazone. Upon confluency, half of the cells treated with FBS or FBS+Dex were treated with insulin, transferrin, and sodium selenite (ITS). The adipogenic response to dexamethasone and troglitazone was most evident in SQ S-V cells from 105 d fetuses. Troglitazone induced adipogenesis is first evident in 75 d SQ S-V cells. The adipogenic response in STM S-V cells is less robust than that of SQ S-V cells regardless of age. It appears that the adipogenic response to either treatment develops earlier in SQ than in STM S-V cells. Nonetheless, these results suggest that fetal subcutaneous and intramuscular adipogenesis can be induced by Dex or thiazolidinedione in later term fetuses. Additionally, myotubes and adipocytes co-developed in S-V cell cultures from 75 d and 90 d fetal pigs. These “co-cultures” could be used in future studies to screen for differential regulation of SQ and intramuscular adipogenesis. These studies provide valuable insight into the development of subcutaneous and intramuscular adipose tissues in swine.