[Show abstract][Hide abstract] ABSTRACT: The present review has been focused largely on the sex type differences in beef quality among heifers, cows, steers and bulls in various feeding environments. Genetic groups, feeding systems and gender are the major factors that change carcass characteristics and fatty acid profiles of cattle. Studies identified that heifer beef has super characteristics in eating quality and a better healthy composition in fatty acids than steer, cow and bull. Diet influences the variation of fatty acid profile; particularly the level of polyunsaturated fatty acids (PUFA) interacts with breed and sex. Animals finished in pasture systems were reported to show better ratios of PUFA/ saturated fatty acids and n-6/n-3. Carcasses of roughage-fed beef are lighter and have less marbling and lower quality grades but have higher cutability than carcasses of grain-fed bulls. Heifers and cows are reported to deposit more fat than steers and bulls. Among males, lower production of testosterone by steers favors more fat thickness compared with bulls. Marbling greatly varies among cattle belonging to different sexes, and particularly, females have genetic makeup that efficiently controls deposition. The current review identified that heifers can be a premium beef brand, while steer beef currently take a large part of market share across the world.
[Show abstract][Hide abstract] ABSTRACT: The present study was carried out to understand the co-culture effect of C2C12 and 3T3-L1 preadipocyte cells on calpain, caspase, and heat shock protein (Hsp) systems. Calpains, caspases, and heat shock proteins play critical roles in the growth and development of mammalian cells. Cells were co-cultured using transwell inserts with a 0.4-μm porous membrane to separate C2C12 and 3T3-L1 preadipocyte cells. Each cell type was grown independently on the transwell plates. Following cell differentiation, inserts containing 3T3-L1 cells were transferred to C2C12 plates and inserts containing C2C12 transferred to 3T3-L1 plates. Following co-culture for 24 and 48 h, the cells in the lower well were harvested for analysis. Calpains include μ-calpain, m-calpain, and their specific inhibitor calpastatin. The expression pattern of μ-calpain did not change in the co-cultured C2C12 and 3T3-L1 cells, whereas m-capain mRNA expression significantly reduced in the 48-h co-cultured 3T3-L1 cells. Calpastatin mRNA expression significantly increased in the 48-h co-cultured C2C12 cells. Caspase-7 mRNA expression did not change in the 24- and 48-h co-cultured C2C12 and 3T3-L1 cells. Caspase-3 mRNA expression significantly reduced in the 24- and 48-h co-cultured 3T3-L1 cells; caspase-9 mRNA had a significant reduction only at 48 h, whereas caspase-9 mRNA expression significantly increased in the 48-h co-cultured C2C12 cells. Hsp27 and Hsp90 mRNA expressions are significantly reduced in the 24- and 48-h co-cultured C2C12 and 3T3-L1 cells, whereas Hsp70 mRNA expression significantly increased in the 48-h co-cultured 3T3-L1 cells. The co-culture reflects three-dimensional views of C2C12 and 3T3-L1 cell types as in vivo, which is quite distinct from the one-dimensional monocultured C2C12 and 3T3-L1 cells.
[Show abstract][Hide abstract] ABSTRACT: The current study was undertaken to determine the effect of the troglitazone (TGZ) on the expression of peroxisome proliferator-activating receptor (PPARγ), CCAAT/enhancer-binding protein, fatty acid binding protein 4, calpain 1 (CAPN1), and lipid accumulation in the myotube of Hanwoo muscle satellite cells. The satellite cells were treated with 5, 10, and 50 μM of TGZ for indicated time intervals. TGZ promoted the trans-differentiation with significant increase in glycerol accumulation. Polymerase chain reaction (PCR) and microarray results indicated that the TGZ treatment significantly increased the expression of adipogenic transcription factors. TGZ (10 and 50 μM) increased the CAPN1 gene expression 2.2- and 2.6-fold in real-time polymerase chain reaction analysis and 0.52- and 0.25-fold in microarray analysis, respectively, when compared with their respective controls. This result suggests that CAPN1 gene might be involved in the adipogenic differentiation programs. In addition, 13 genes were upregulated and 12 genes were downregulated in microarray analysis. Most of the up/downregulated genes were directly linked with adipogenesis.
Journal of physiology and biochemistry 07/2012; · 1.65 Impact Factor