Transdifferentiation of porcine satellite cells to adipoblasts with ciglitizone1

Abstract

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.

Intramuscular fat content in meat-producing animals: development, genetic and nutritional control, and identification of putative markers

“…Another complexity in the regulation of intramuscular adipocyte development is added by the possible existence of interconversion of muscle satellite cells into adipocytes as shown in vitro (Kook et al, 2006;Singh et al, 2007;for review, see Chung and Johnson, 2008). It remains, however, to be determined whether this phenomenon also exists in vivo, and may account for fat infiltration into muscles observed following denervation (Dulor et al, 1998) or sarcopenia (for review, see Pahor and Kritchevsky, 1998).…”

Review: Animal model and the current understanding of molecule dynamics of adipogenesis

“…Similarly, MSCs respond to high concentrations of the same transcription factors. However, these factors appear to inhibit myogenic differentiation Campos, Duarte, Guimarães, Verardo, Wei, Du, Jiang, Bergen, Fernyhough-Culver, Albrecht and Dodson stimulating adipogenesis and also appears to inhibit myogenic differentiation, while ensuring adipogenic differentiation (Teboul et al, 1995;Taylor-Jones et al, 2002;Singh et al, 2007;. Considering this, the study of adipogenesis and its effects on the accumulation of IMF can be used not only to understand fat deposition in livestock, but also for a better comprehension of the differentiation process in mesenchymal stem cells.…”

“…SC are multipotent cells capable of transdifferentiating into intramuscular adipocytes when exposed to local cellular signaling (Taylor-Jones et al, 2002;Singh et al, 2007;Lee et al, 2012;Ryan et al, 2013). Moreover, muscle side population (SP) cells are multipotent stem cells that can participate in myogenesis and muscle regeneration upon transplantation (Penton et al, 2013).…”

“…This might not be totally accountable by the decrease in stem cell activity; myogenic transdifferentiation into adipocytes also play a role in this phenomena. Since MSCs are multipotent, their transdifferentiation into intramuscular adipocytes is feasible, depending on different cellular signaling exposure, thereby leading to greater amounts of IMF (if the adipocytes invade the perimysium) (Taylor-Jones et al, 2002;Singh et al, 2007;Aguiari et al, 2008;Lee et al, 2012). …”

High glucose induces differentiation and adipogenesis in porcine muscle satellite cells via mTOR

“…Studies have demonstrated that muscle satellite cells can differentiate into adipocytes following treatments with adipogenic inducers (2,3).…”