Project description:Frailty of the locomotory organs has become a widespread problem in the geriatric population. The major factor leading to frailty is an age-associated decrease in muscular mass and a reduced number of muscular cells and myofibers. To understand why decrease self-renew at he gene expression profile the diffeerences between aged and young Muscle progenitor cells(MPSCs). In aged muscular tissues, muscle progenitor cells(MPSCs) are reduced due to abnormalities in their self-renewal and the induction of apoptosis. However, the molecular mechanisms connecting aging-associated physiological changes and the reduction of MPSCs are largely unknown. In this study, we compared the gene expression profile of young and aged MPSCs to identify genes involved in the reduction of MPSCs.
Project description:Our laboratory wanted to define the transcription profile of aged skeletal muscle. For this reason, we performed a triplicate microarray study on young (3 weeks) and aged (24 months) gatrocnemius muscle from wild-type C57B16 Mice Keywords: other this experiment include 2 samples and 6 replicates
Project description:Our laboratory wanted to define the transcription profile of aged skeletal muscle. For this reason, we performed a triplicate microarray study on young (3 weeks) and aged (24 months) gatrocnemius muscle from wild-type C57B16 Mice Keywords: other
Project description:Age-related impairments in myoblast differentiation may contribute to reductions in muscle function in older adults but the underlying proteostasis processes are not well understood. We investigated young (P6-10) and replicatively aged (P48-50) C2C12 myoblast cultures during early (0h-24h) and late (72h-96h) stages of differentiation using deuterium oxide (D2O) labelling and mass spectrometry. The absolute dynamic profiling technique for proteomics (Proteo-ADPT) was used to quantify the absolute rates of abundance change, synthesis and degradation of individual proteins. Proteo-ADPT encompassed 116 proteins and 74 proteins exhibited significantly (P<0.05, FDR <5 %) different changes in abundance between young and aged cells at early and later periods of differentiation. Young cells exhibited a steady pattern of growth, protein accretion and fusion, whereas aged cells failed to gain protein mass or undergo fusion during later differentiation. Maturation of the proteome was retarded in aged myoblasts at the onset of differentiation, but the proteome appeared to ‘catch up’ with the young cells during the early differentiation period. However, this ‘catch up’ process in aged cells was not accomplished by higher levels of protein synthesis. Instead, a lower level of protein degradation in aged cells was responsible for the elevated gains in protein abundance. Our novel data point to a loss of proteome quality as a precursor to the lack of fusion of aged myoblasts and highlights dysregulation of protein degradation, particularly of ribosomal and chaperone proteins, as a key mechanism that may contribute to age-related declines in the capacity of myoblasts to undergo differentiation.
Project description:To identify Pax7 target genes in muscle progenitor cells, we compared the transcriptome profiles of muscle progenitor cells from young mice (P12) with and without Pax7.
Project description:Sarcopenia is the age-induced, progressive loss of skeletal muscle mass and function, which results in poor muscle performance. To better understand changes in skeletal muscles during sarcopenia, we performed a metabolomic analysis of skeletal muscle in young (8-week-old) and aged (28-month-old) mice using CE-TOFMS. Our data shows that the metabolites including glucose and polyamine metabolism were decreased in aged mice compared with young mice. In addition, neurotransmitter levels were higher in aged mice.
Project description:Comprehensive analyses of mRNA expression were performed using three different cell populations isolated from skeletal muscle of young and aged mice to investigate age-related changes of each cell population.
Project description:Background: Age-related physiological, biochemical and functional changes in mammalian skeletal muscle have been shown to begin at the mid-point of the lifespan. However, the underlying changes in DNA methylation that occur during this turning point of the muscle aging process have not been clarified. To explore age-related genomic methylation changes in skeletal muscle, we employed young (0.5 years old) and middle-aged (7 years old) pigs as models to survey genome-wide DNA methylation in the longissimus dorsi muscle using a methylated DNA immunoprecipitation sequencing approach. Results: We observed a tendency toward a global loss of DNA methylation in the gene-body region of the skeletal muscle of the middle-aged pigs compared with the young group. We determined the genome-wide gene expression pattern in the longissimus dorsi muscle using microarray analysis and performed a correlation analysis using DMR (differentially methylated region)-mRNA pairs, and we found a significant negative correlation between the changes in methylation levels within gene bodies and gene expression. Furthermore, we identified numerous genes that show age-related methylation changes that are potentially involved in the aging process. The methylation status of these genes was confirmed using bisulfite sequencing PCR. The genes that exhibited a hypomethylated gene body in middle-aged pigs were over-represented in various proteolysis and protein catabolic processes, suggesting an important role for these genes in age-related muscle atrophy. In addition, genes associated with tumorigenesis exhibited aged-related differences in methylation and expression levels, suggesting an increased risk of disease associated with increased age. Conclusions: This study provides a comprehensive analysis of genome-wide DNA methylation patterns in aging pig skeletal muscle. Our findings will serve as a valuable resource in aging studies, promoting the pig as a model organism for human aging research and accelerating the development of comparative animal models in aging research. We collected the longissimus dorsi muscles tissue from Jinhua pigs which aged 0.5 year and seven years and study the genome-wide DNA methylation difference between the two age periods.