Submitted to: Journal of Animal Science
Publication Type: Abstract Only
Publication Acceptance Date: May 20, 2003
Publication Date: June 22, 2003
Citation: POULOS, S.P., HAUSMAN, G.J. PREADIPOCYTE RECRUITMENT IS ENHANCED BY CIGLITAZONE OR TROGLITAZONE IN SUBCUTANEOUS ADIPOSE STROMAL-VASCULAR (S-V) CELL CULTURES BUT NOT INTRAMUSCULAR S-V CELL CULTURES.. JOURNAL OF ANIMAL SCIENCE. 2003. v. 81(Suppl.1): Abstract p. 94. Technical Abstract: Intramuscular adiposity enhances marketability of meat products. Our understanding of intramuscular adipocyte development is limited. Though studies have shown marbling fat can be modified, intramuscular S-V cultures show these cells do not respond to dexamethasone similar to subcutaneous cells. The aim of this study was to determine the adipogenic potential of porcine S-V cells from subcutaneous adipose tissue (SQ) and semitendinosus muscles (STM) using the insulin sensitizing agents, ciglitazone or troglitazone. SQ and both STM from 5-7 day old pigs were asceptically removed and S-V cells obtained from each tissue following a standard collagenase digestion. STM S-V cells were plated on laminin coated culture dishes to maintain a myotube-rich environment. S-V cells from each tissue were plated in media containing fetal bovine serum and 0.01%DMSO supplemented with 0, 10, 25, 50'M ciglitazone or troglitazone. Upon confluency, cells were switched to insulin containing media for 3 days. Immunohistological evaluation for AD3, a preadipocyte antibody, was used to assess preadipocyte recruitment. Differences between treatments were determined using least square contrasts and p<0.05 was considered significant. AD3 cell number per microscopic field was increased in SQ cultures as compared to STM cultures (24.1 ± 16.4 SQ, 9.8 ± 5.5; p<0.0001) regardless of treatment. A dose response curve reveals 10'M ciglitazone or troglitazone treatment increases AD3 cell number per field in SQ S-V cultures (15.3 ± 7.8, DMSO control; 30.5 ± 7.8, ciglitazone, 38.9 ± 7.8, troglitazone; p<0.05) though increasing doses in either treatment did not increase AD3 cell number. This is in contrast to STM S-V cultures which did not show an increase in AD3 at 10, 25, or 50 'M ciglitazone or troglitazone treatment (p>0.05). Myotube formation in STM S-V cultures was maintained regardless of treatment. These results suggest intramuscular adipogenesis regulation may be different than that of adipogenesis in subcutaneous adipose. This information is key to the use of STM S-V as a cell model system for marbling fat.