Ectopic overexpression of swine PPARγ2 upregulated adipocyte genes expression and triacylglycerol in skeletal muscle of mice.

Peroxisome proliferator-activated receptor γ2 (PPARγ2) is a key regulator of adipocyte differentiation, fatty acid uptake and storage in mammals. The primary goal of the present study was to investigate the consequences of PPARγ2 overexpression in the muscle. A swine muscle creatine kinase promoter was used to drive swine PPARγ2 (sPPARγ2) overexpression in the muscle of a transgenic mice model. The results showed that the mRNA of multiple adipocyte genes was increased in the skeletal muscle, as evidenced by the up-regulation of fatty acid synthase (2.11-fold, P < 0.05), lipoprotein lipase (2.08-fold, P < 0.01), fatty acid-binding protein 4 (14.30-fold, P < 0.01), and CD36 antigen (5.50-fold, P < 0.01). Meanwhile, skeletal muscle triacylglycerol was increased (P < 0.01) and the fatty acid profile of muscle fat was changed in that more polyunsaturated fats acid were augmented. The present study may further serve to develop transgenic pigs with higher intramuscular fat content and improved pork quality.