Project description:Traumatic skeletal muscle fibrosis is disastrous to muscle performance. In this dataset, mice gastrocnemius was subjrct to contusion injury and then measured by miRNA microarray to identify potential therapeutic targets.
Project description:Excerpt from a larger study which characterized the transcriptional effects of a spinal cord contusion injury in rats. This is the data from the almost chronic contusion state (35 days) at the injury site (Thoracic 8) - where we saw significant changes in several areas, including cholesterol metabolism genes. Other spinal cord areas (rostral, caudal) and time-points (3 hours, 24 hours, 7 days and 35 days) were analyzed as well and are discussed in our paper and at www.crpf.org/microarray.
Project description:Northern elephant seals (NES, Mirounga angustirostris) undergo an annual molt during which they spend ~40 days fasting on land with reduced activity and lose approximately one-quarter of their body mass. Reduced activity and muscle load in stereotypic terrestrial mammalian models results in decreased muscle mass and capacity for force production and aerobic metabolism. However, the majority of lost mass in fasting female NES is from fat while muscle mass is largely preserved. Although muscle mass is preserved, potential changes to the metabolic and contractile capacity are unknown. To assess potential changes in NES skeletal muscle during molt, we collected muscle biopsies from 6 adult female NES at the beginning of the molt and after ~30 days at the end of the molt. Skeletal muscle was assessed for respiratory capacity using high resolution respirometry, and RNA was extracted to assess changes in gene expression. Despite a month of reduced activity, fasting, and weight loss, skeletal muscle respiratory capacity was preserved with no change in OXPHOS respiratory capacity. Molt was associated with 162 upregulated genes including genes favoring lipid metabolism and regulating cell cycles. We identified 172 downregulated genes including those coding for ribosomal proteins and genes associated with skeletal muscle force transduction and glucose metabolism. Following ~30 days of molt, NES skeletal muscle metabolic capacity appears largely preserved although mechanotransduction may be compromised. In the absence of exercise stimulus, fasting-induced shifts in skeletal muscle lipid metabolism may stimulate lipid signaling pathways associated with preserving the mass and metabolic capacity of slow oxidative muscle.
Project description:TK2 deficiency causes severe mtDNA depeltion in several tissues, including skeletal muscle and heart. TK2 knockout mice grow slower and their skeletal muscles appeared significantly underdeveloped, whereas heart was close to normal size. We used microarrays in order to compare the transcriptomes in skeletal muscle and heart tissue of 11 days-old TK2 knockout pups with the sames tissues of wild-type pups at the same age. We collected skeletal muscle from the hind limb and hearts of three 11 days-old TK2 knockout and three wild-type pups and extracted total RNA. These RNA samples were used for hybridization in Affymetrix arrays.
Project description:TK2 deficiency causes severe mtDNA depeltion in several tissues, including skeletal muscle and heart. TK2 knockout mice grow slower and their skeletal muscles appeared significantly underdeveloped, whereas heart was close to normal size. We used microarrays in order to compare the transcriptomes in skeletal muscle and heart tissue of 11 days-old TK2 knockout pups with the sames tissues of wild-type pups at the same age.
Project description:MicroRNAs (miRNAs) are small, non-coding RNAs that play a critical role in regulating gene expression post-transcriptionally. Skeletal muscle-specific miRNAs, including miR-1, are important for skeletal muscle development and maintenance. In response to mechanical loading, skeletal muscle levels of miR-1 decrease by approximately 50%, suggesting a potential involvement in muscle hypertrophy. In the current investigation, we hypothesized that a reduction of miR-1 levels in response to mechanical loading would be necessary for skeletal muscle growth to occur. By significantly elevating miR-1 levels during the hypertrophic process via lentiviral delivery, we observed a blunted growth response in the plantaris muscle subjected to synergist ablation. A deeper RNA-based integrative analysis (transcriptomics and RNA eCLIP) indicates that miR-1 inhibits the expression of Itm2a and Melusin, two membrane-related proteins. While their exact mechanism in muscle hypertrophy is yet to be identified, our results suggest that miR-1-regulated membrane proteins are important for skeletal muscle hypertrophy.
Project description:The purpose of this study was to determine the miRNA expression profile of in vitro differentiation of human skeletal muscle cells and to couple changes in individual miRNA expression to transcriptional output of target genes. miRNA expression profiling at six different time points during the in vitro differentiation process of human skeletal muscle cells from six subjects. RNA was harvested from myoblasts before induction of differentiation and at every other day for 10 following days.