G.P.210: Gene expression profile of satellite cells from Largemyd and Lama2dy2j/J, murine models for muscular dystrophies

Abstract

Muscle satellite cells have been widely studied, especially to understand their mechanism of action in muscle regeneration and correspondent implications in the different dystrophic processes. Two mice models for muscular dystrophies, Largemyd and Lama2dy2j/J, have a pattern of an intense and very similar degeneration, but with differences in the expression of genes involved in the regeneration cascade, as we shown in our recent work. Therefore, they are interesting models to study possible differences in the mechanism of activation and action of satellite cells in the dystrophic muscle. The main objective of this work was to evaluate gene expression profile of the satellite cells from both dystrophic mouse models, as compared to normal murine muscle, to try to explain the difference observed in the respective muscles. For this evaluation, we harvested muscle derived cells after enzyme dissociation of muscle tissue. The cells were then pre-plated in culture flasks (PP1) and re-plated after 24 h (PP2). The different populations were than characterized by flow cytometry markers and analyzed using a murine gene expression microarray panel of more than 26,000 genes. We observed 383 differentially expressed genes in Largemyd and 110 in Lama2dy2j/J. The glycosilation alteration, exhibited by Largemyd alters the expression of many genes, especially those involved with myogenesis and activation of cell differentiation. The altered genes of Lama2dy2j/J are more related with cell membrane or extracellular matrix. These observations are corroborating our previous gene expression results, suggesting that the mutation present in Largemyd mouse leads to defects in the regeneration potential of satellite cells, what does not occur in the Lama2dy2j/J model. Muscle satellite cells have been widely studied, especially to understand their mechanism of action in muscle regeneration and correspondent implications in the different dystrophic processes. Two mice models for muscular dystrophies, Largemyd and Lama2dy2j/J, have a pattern of an intense and very similar degeneration, but with differences in the expression of genes involved in the regeneration cascade, as we shown in our recent work. Therefore, they are interesting models to study possible differences in the mechanism of activation and action of satellite cells in the dystrophic muscle. The main objective of this work was to evaluate gene expression profile of the satellite cells from both dystrophic mouse models, as compared to normal murine muscle, to try to explain the difference observed in the respective muscles. For this evaluation, we harvested muscle derived cells after enzyme dissociation of muscle tissue. The cells were then pre-plated in culture flasks (PP1) and re-plated after 24 h (PP2). The different populations were than characterized by flow cytometry markers and analyzed using a murine gene expression microarray panel of more than 26,000 genes. We observed 383 differentially expressed genes in Largemyd and 110 in Lama2dy2j/J. The glycosilation alteration, exhibited by Largemyd alters the expression of many genes, especially those involved with myogenesis and activation of cell differentiation. The altered genes of Lama2dy2j/J are more related with cell membrane or extracellular matrix. These observations are corroborating our previous gene expression results, suggesting that the mutation present in Largemyd mouse leads to defects in the regeneration potential of satellite cells, what does not occur in the Lama2dy2j/J model.