Project description:The right legs of 8 Brown-Norway male rats were denervated by a high sciatic nerve section in the hip region of the hind limb.Two months after denervation (6 months of age), extensor digitorum longus (EDL) muscles were removed from the operated legs. The EDL muscles from 8 age-matched non-operated rats served as innervated controls. Total RNA was isolated, labeled cDNA was prepared and hybridized to the Rat Atlas 1.2 Array II membranes (Clontech Laboratories, Palo Alto, CA).
Project description:The right legs of 8 Brown-Norway male rats were denervated by a high sciatic nerve section in the hip region of the hind limb.Two months after denervation (6 months of age), extensor digitorum longus (EDL) muscles were removed from the operated legs. The EDL muscles from 8 age-matched non-operated rats served as innervated controls. Total RNA was isolated, labeled cDNA was prepared and hybridized to the Rat Atlas 1.2 Array II membranes (Clontech Laboratories, Palo Alto, CA). Keywords: other
Project description:Muscle denervation causes skeletal muscle atrophy. The goal of these studies was to determine the effects of denervation on skeletal muscle mRNA levels in C57BL/6 mice. For additional details see Ebert et al, Stress-Induced Skeletal Muscle Gadd45a Expression Reprograms Myonuclei and Causes Muscle Atrophy. JBC epub. June 12, 2012. Left sciatic nerves of C57BL/6 mice were transected. Seven days later bilateral tibialis anterior muscles were harvested. mRNA levels in denervated muscles were normalized to levels in contralateral innervated muscles.
Project description:To identify novel atrophy-related genes, which are controlled by BMP signaling, we performed gene expression profiling on innervated and 14 days denervated muscles of Smad4 knockout and control mice, focusing on genes that were differentially upregulated in denervated Smad4-/- muscles compared to controls. Among the different genes our attention was attracted by a gene that encodes for a novel f-box protein (Fbxo30) belonging to the SCF complex family of the ubiquitin ligases. Cell size is determined by the balance between protein synthesis and degradation. This equilibrium is affected by hormones, nutrients, energy levels, mechanical stress and cytokines. Mutations that inactivate Myostatin lead to important muscle growth in animals and humans. However, the signals and pathways responsible for this hypertrophy remain largely unknown. Here we find that BMP signaling, acting through Smad1/5/8, is the fundamental hypertrophic signal. Inhibition of BMP signaling causes muscle atrophy, abolishes the hypertrophic phenotype of Myostatin knockout and strongly exacerbates the effects of denervation and fasting. BMP-Smad1/5/8 negatively regulates a novel gene (Fbxo30) that encodes an ubiquitin ligase, that is required for muscle loss. Collectively, these data identify a critical role for the BMP pathway in adult muscle maintenance, growth and atrophy. Gene expression profiling on innervated and 14 days denervated muscles of Smad4 knockout and control mice. Three independent experiments were performed for each experimental condition using different animals for each experiment.
Project description:Knee osteoarthritis (KOA), as a degenerative multifactorial disease, affects the quality of life and mental health of patients, and also brings a huge socioeconomic burden. Treating synovitis have shown promise as anti-inflammatory therapeutics in mitigating OA symptoms and disease progression. Here, by analysing synovial single-cell sequencing (scRNA-seq) data from KOA, we found that synovial fibroblasts (FLS) in OA synovium showed a distinct pro-inflammatory phenotype. We collected synovial tissue from patients with clinical OA as well as from healthy donors, and histological examination was consistent with findings in scRNA-seq. Inspired by recent cross-tissue fibroblast lineage studies, we identified by sequencing that healthy FLS in synovial tissues share transcriptome-level similarities with dermal fibroblasts (DFb). Subsequently, we revealed the local as well as systemic distribution of intra-articular injected DFbs by constructing/extracting two types of rat fibroblasts (luciferase DFbs as well as GFP DFbs). The results demonstrate that DFbs can be locally retained in the synovium for up to three weeks following targeted engrafting on it. And intra-articular injection does not result in DFbs migration to vital organs or the occurrence of histological changes in these organs. A rat model of KOA was constructed by anterior cruciate ligament transection (ACLT) in order to study the therapeutic effect of DFbs on KOA. After injection, the rats showed improvement in painful gait. In addition, histological as well as imaging results showed reduced synovitis and improvement in articular cartilage. Finally we verified the protective effect of DFbs on cytokine-stimulated chondrocytes in a co-culture system.
Project description:Here we report genome wide estimation of expression profiles at promoter level in Soleus and EDL muscles in rat hindlimbs under unloading conditions.
Project description:In order to establish a rat embryonic stem cell transcriptome, mRNA from rESC cell line DAc8, the first male germline competent rat ESC line to be described and the first to be used to generate a knockout rat model was characterized using RNA sequencing (RNA-seq) analysis.