Ciglitizone, a class of thiazolidinediones, acts as a potent activator of the adipose differentiation program in established preadipose cell lines. Thiazolidinediones have also been investigated in diabetic patients and have been reported to act as peroxisome proliferator-activated receptor-gamma ligands. Intramuscular adipogenesis or marbling through transdifferentiation of satellite cells in cattle was successfully conducted earlier. In this report, the effects of ciglitizone on the differentiation pathway of porcine myogenic satellite cells was investigated. Semitendinosus muscle was aseptically taken from 10-d-old piglets under general anesthesia, and porcine satellite cells were obtained and grown to near confluence. Postconfluent cells (d 0) were further cultured in differentiation medium containing an adipogenic mixture plus ciglitizone (10 microM) for 48 h. From d 2 onward, the cells were cultured only in the presence of ciglitizone until d 10. Controls were cultured in differentiation medium only. Exposure of porcine satellite cells to the adipogenic mixture plus ciglitizone generated lipid droplets on d 2, and subsequently, exposure of cells to ciglitizone alone helped in cytoplasmic lipid filling, providing them with the acquisition of adipocyte morphology. An increase (P < 0.05) in the fusion (structures containing 2 to 3 nuclei) of satellite cells was observed, and myosin heavy chain appeared with greater intensity (immunohistochemistry) in the control group from d 2 onward. Adipocyte-specific transcriptional factors (i.e., CCAAT/enhancer binding protein-alpha and peroxisome proliferator-activated receptor-gamma) were predominant during transdifferentiation and were observed with immunohistochemistry, Western blot (approximately 47.2 and approximately 60.4 kDa, respectively), and real-time PCR. Ciglitizone appeared to convert the differentiation pathway of satellite cells into that of adipoblasts.

Abstract. Seedlings of four Quercus species dominant in Korea (Quercus mongolica, Quercus serrata, Quercus acutissima, and Quercus variabilis) were grown at different CO 2 levels (ambient; 380 ppmv and enriched; 800 ppmv) to determine growth responses under elevated CO 2 . Three weeks after germination, seedlings were transplanted into chambers and grown over a period of 105 days. Aboveground plant parts were harvested at the end of the experiment to measure dry weight, leaf area, specific leaf area (SLA), leaf area ratio (LAR), leaf weight ratio (LWR), and leaf quality (carbon, nitrogen). Q. mongolica exhibited increased growth, Q. serrata and Q. acutissima did not respond to enrichment, and the growth of Q. variabilis was diminished with elevated CO 2 . Total aboveground biomass of each seedling increased by 31% for Q. mongolica, but for Q. variabilis, it decreased significantly by 39% under CO 2 -enriched conditions (p < 0.05). SLA and LAR decreased, and LWR was unchanged or decreased slightly in the elevated CO 2 treatment for all species, with the exception of Q. acutissima. In addition, the elevated CO 2 treatment was correlated with a decrease in total N concentrations, and an increase in the C/N ratio of the leaves of Q. mongolica and Q. acutissima. In conclusion, plant growth responses to elevated CO 2 were species-specific, and they showed large interspecific variation.