Dataset Information

A Non-invasive Mouse Model That Recapitulates Disuse-Induced Muscle Atrophy in Immobilized Patients

ABSTRACT: Disuse muscle atrophy occurs consequent to prolonged limb immobility or bed rest, which represents an unmet medical need. As existing animal models of limb immobilization often cause skin erosion, edema, and other untoward effects, we here report an alternative method via thermoplastic immobilization of hindlimbs in mice. While significant decreases in the weight and fiber size were noted after 7 days of immobilization, no apparent skin erosion or edema was found. To shed light onto the molecular mechanism underlying this muscle wasting, we performed the next-generation sequencing analysis of gastrocnemius muscles from immobilized versus non-mobilized legs. Among a total of 55,487 genes analyzed, 787 genes were differentially expressed (> 4-fold; 454 and 333 genes up- and down-regulated, respectively), which included genes associated with muscle tissue development, muscle system process, protein digestion and absorption, and inflammation-related signaling. To the best our knowledge, this is the first study that used RNA-seq to reveal changes in the skeletal muscle transcriptome profiling in response to disuse atrophy without denervation. From a clinical perspective, this model may help understand the molecular/cellular mechanism that drives muscle disuse and identify therapeutic strategies for this debilitating disease.

ORGANISM(S): Mus musculus

PROVIDER: GSE237537 | GEO | 2023/12/06

REPOSITORIES: GEO

ACCESS DATA

Similar Datasets

Project description:Advancements in animal models and cell culture techniques have been invaluable in the elucidation of molecular events and mechanisms regulating muscle atrophy. However, few studies have examined muscle atrophy in humans using modern experimental techniques. The purpose of this study was to examine and validate changes in global gene transcription during immobilization-induced muscle atrophy in humans. Healthy men and women (N=24) were subjected to two weeks of unilateral limb immobilization, with muscle biopsies obtained before, and after 48 hours (48H) and 14 days (14D) of immobilization. Both muscle cross sectional area (~ 5 %) and strength (10-20 %) were significantly reduced in men and women after 14D of immobilization. Micro-array analysis of total RNA extracted from biopsy samples uncovered 575 and 3,128 probes representing multiple genes, which were significantly altered at 48H and 14D, respectively. As a group, genes involved in mitochondrial bioenergetics and carbohydrate metabolism were predominant features at both 48H and 14D, with genes involved in protein synthesis and degradation significantly down-regulated and up-regulated, respectively, at 14D of muscle atrophy. There was also a significant decrease in the protein content of mitochondrial cytochrome c oxidase, and the enzyme activity of cytochrome c oxidase and citrate synthase after 14D of immobilization. Furthermore, protein ubiquitination and oxidative damage were significantly increased by 48H and 14D of immobilization, respectively. These results suggest that transcriptional and post-transcriptional suppression of mitochondrial processes is sustained throughout 14D of immobilization, while protein ubiquitination plays an early but transient role in the progression of immobilization-induced muscle atrophy in humans. 72 samples taken from quadriceps of healthy ambulatory young men and women. Samples were taken at 3 timepoints throughout a 14 day period, the initial sample was taken at time 0 (PRECAST), then the limb was immobilized via a brace, and the 2nd sample was taken at 48 hours (CAST02D). The third sample was taken following 14 days of immobilization (CAST14D).

Project description:Hibernation is energy saving adaptation involving suppression of activity to survive in highly seasonal environments. Immobility and disuse generate muscle loss in most mammalian species. In contrast to other mammals, bears and ground squirrels demonstrate limited muscle atrophy over the physical inactivity of winter hibernation. This suggests that hibernating mammals have adaptive mechanisms to prevent disuse muscle atrophy. To identify common transcriptional program underlying molecular mechanisms preventing muscle loss, we conducted a large-scale gene expression screening in hind limb muscles comparing hibernating and summer active black bears and arctic ground squirrels by the use of custom 9,600 probe cDNA microarrays. The molecular pathway analysis showed an elevated proportion of overexpressed genes involved in all stages of protein biosynthesis and ribosome biogenesis in muscle of both species during hibernation that implies induction of translation at different hibernation states. The induction of protein biosynthesis likely contributes to attenuation of disuse muscle atrophy through prolonged periods of immobility and starvation. This adaptive mechanism allows hibernating mammals to maintain full musculoskeletal function and preserve mobility during and immediately after hibernation, thus promoting survival. The lack of directional changes in genes of protein catabolic pathways does not support the importance of metabolic suppression for preserving muscle mass during winter. Coordinated reduction of multiply genes involved in oxidation reduction and glucose metabolism detected in both species is consistent with metabolic suppression and lower energy demand in skeletal muscle during inactivity of hibernation. Black bears sampled during winter hibernation were compared with the animals sampled during summer. Muscle tissue were hybridized on a custom 12,800 cDNA probe nylon membrane microarray platform . Six hibernating and six summer active bears were studied in the experiment.

Dataset Information

A Non-invasive Mouse Model That Recapitulates Disuse-Induced Muscle Atrophy in Immobilized Patients

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure