Submitted to: Journal of Animal Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: December 7, 2005
Publication Date: May 20, 2006
Citation: Poulos, S.P., Hausman, G.J. 2006. A comparison of thiazolidinedione-induced adipogenesis and myogenesis in stromal-vascular cells from subcutaneous adipose tissue or semitendinosus muscle from postnatal pigs. Journal of Animal Science. 84(5):1076-1082. Interpretive Summary: Thiazolidinediones are drugs that are used to treat type 2 diabetes. The two thiazolidinediones used in this study were troglitazone and ciglitazone. This study shows that thiazolidinediones can induce development of new fat cells from fat tissue and skeletal muscle precursor cells. Of the two drugs, troglitazone appears to stimulate fat cell development more that ciglitazone. These effects on precursor cells from skeletal muscle are independent of muscle cell development. This suggests that the development of fat cells in skeletal muscle or marbling fat cells could be enhanced by troglitazone.
Technical Abstract: This study was undertaken to compare the adipogenic potential of porcine stromal-vascular (S-V) cells from semitendinosus muscles (STM) and subcutaneous adipose tissue (SQ) using thiazolidinediones. S-V cells were obtained from SQ and both STM from 5-7 d old pigs following collagenase digestion. Preadipocyte recruitment was measured using immunohistological evaluation for AD3, a preadipocyte antibody. Ciglitazone increased AD3 cell number in SQ but not STM cells while 10 'M troglitazone increased AD3 abundance in both SQ and STM S-V cells by approximately 3 fold (P<0.05). Increasing troglitazone doses did not further increase AD3 cell number. Increases in AD3 cells are paralleled by increases in C/EBP' and PPAR' positive cells in SQ cultures while PPAR', but not C/EBP', reactive cells were increased in STM cultures treated with 10 'M troglitazone. Additionally, troglitazone treatment did not increase lipid content in SQ or STM cultures. Cells plated on laminin pre-coated culture dishes were used to determine whether troglitazone influences adipogenesis or myogenesis in co-cultures from STM S-V cells. There was no effect on the number of myotubes or average number of nuclei per myotube suggesting myogenesis is not impaired in this model. These results suggest that regulation of intramuscular adipogenesis differs from subcutaneous adipogenesis.