ABSTRACT: Inclusion body myopathy associated with Paget disease of bone and frontotemporal dementia (IBMPFD) is caused by mutations in the Valosin Containing Protein (VCP) gene on chromosome 9p12-13. To elucidate affected signaling transduction axes in IBMPFD, we determined expression profiles using microarray technology in quadriceps muscle from patients and unaffected relatives. Muscle from 10 individuals (7 affected, 3 unaffected first degree relatives) was obtained after informed consent for the muscle biopsy was obtained.
Project description:Inclusion body myopathy associated with Paget disease of bone and frontotemporal dementia (IBMPFD) is caused by mutations in the Valosin Containing Protein (VCP) gene on chromosome 9p12-13. To elucidate affected signaling transduction axes in IBMPFD, we determined expression profiles using microarray technology in quadriceps muscle from patients and unaffected relatives.
Project description:Eccentric exercise (ECC) can result in ultra-structural and histological damage to skeletal muscle. The damage incurred following ECC is typically followed by a subsequent regenerative and adaptive response. The specific mechanisms that drive this response, particularly in human muscle, are not well understood. The objective of this study was to characterize the early molecular response in skeletal muscle following ECC in humans. We used an Agilent whole human genome microarray to assess global gene expression in male subjects (N=35) at 3 hours post-100 eccentric contractions of the knee extensors. ANCOVA (age and BMI covariates) was used to compare mRNA expression between the ECC and non-exercised (CON) legs of each subject. Novel transcripts from IPA identified networks were confirmed with quantitative real-time (qRT)-PCR. qRT-PCR analysis of 3 of these transcripts (IkBα, TNFRSF1A and ICAM-1) confirmed changes observed in the microarray analysis. 35 male subjects performed an eccentric exercise protocol consisting of 100 maximal eccentric contrations of the knee extensors. 3 hours after the completion of the exercise regimen, a muscle biopsy was taken from the vastus lateralis of both legs. The non-exercised leg served as the control. Gene expresssion was analyzed using an ANCOVA, with covariates for age and BMI.
Project description:We determined the expression profiles in skeletal muscle from people with type 2 diabetes, first degree relatives, and healthy control individuals by microarray experiments. All subjects were Caucasian males and biopsies were taken after a controlled metabolic period of a two hour hyperinsulinemic euglycemic clamp. Our results show for the first time that insulin signaling is significantly downregulated in people with type 2 diabetes, whereas it is significantly upregulated in first degree relatives. Furthermore, we identify several new genes in skeletal muscle from first degree relatives that have an altered gene expression compared to healthy controls.
Project description:Facioscapulohumeral muscular dystrophy (FSHD) is a progressive neuromuscular disorder caused by contractions of repetitive elements within the macrosatellite D4Z4 on chromosome 4q35. In order to develop mRNA-based biomarkers of affected muscles, we used GeneChip Gene 1.0 ST arrays for global analysis of gene expression in muscle biopsy specimens obtained from FSHD subjects and their unaffected first degree relatives. FSHD typically affects biceps muscles more severely than deltoid muscles. To examine muscle-specific expression changes associated with FSHD while controlling for background genetic variation, we analyzed RNA extracted from both biceps and deltoids of FSHD subjects and unaffected first-degree relatives.
Project description:Background: Exercising is know to have an effect on exercising skeletal muscle, but unkown is the effect on non-exercising skeletal muscle. Gene expression changes in the non-exercising skeletal muscle would point to a signalling role of skeletal muscle 9 healthy middle-aged men performed 1 hour of one-legged exercise, before and afterwards muscle biopsies were taken from both legs. Skeletal muscle biopsies were analyzed by microarray.
Project description:The experiment is part of a study using systems biology approach to analyze muscle gene expression and UPLC-MS based plasma lipidomics profiling data to illuminate relevant biological pathways and to find potential biomarker candidates related to statin-induced changes in muscle metabolism.
Project description:Septic patients treated in the intensive care unit (ICU) often develop multiple organ failure including persistent skeletal muscle dysfunction which results in the patientâs protracted recovery process. We have demonstrated that muscle mitochondrial enzyme activities are impaired in septic ICU patients resulting in decreased cellular energy which will interfere with muscle function and metabolism. Here we use detailed phenotyping and genomics to elucidate mechanisms leading to these impairments. Methodology/Principle Findings Utilising biopsy material from seventeen patients and ten age-matched controls we demonstrate that neither mitochondrial in vivo protein synthesis nor expression of mitochondrial genes are compromised. Indeed, there was partial activation of the mitochondrial biogenesis pathway involving NRF2?/GABP and its target genes TFAM, TFB1M and TFB2M yet clearly this failed to maintain mitochondrial function. We therefore utilised transcript profiling and pathway analysis of ICU patient skeletal muscle to generate insight into the molecular defects driving loss of muscle function and metabolic homeostasis. Gene ontology analysis of Affymetrix analysis demonstrated substantial loss of muscle specific genes, a global oxidative stress response related to most probably cytokine signalling, altered insulin related signalling and a substantial overlap between patients and muscle wasting/inflammatory animal models. MicroRNA 21 processing appeared defective suggesting that post-transcriptional protein synthesis regulation is altered by disruption of tissue microRNA expression. Finally, we were able to demonstrate that the phenotype of skeletal muscle in ICU patients is not merely one of inactivity, it appears to be an actively remodelling tissue, influenced by several mediators, all of which may be open to manipulation with the aim to improve clinical outcome. Conclusions/Significance This first combined protein and transcriptome based analysis of human skeletal muscle obtained from septic patients demonstrated that losses of mitochondria and muscle mass are accompanied by sustained protein synthesis (anabolic process) while dysregulation of transcription programmes appears to fail to compensate for increased damage and proteolysis. Our analysis identified both validated and novel clinically tractable targets to manipulate these failing processes and pursuit of these could lead to new potential treatments. Experiment Overall Design: 13 septic samples, 8 controls
Project description:We assessed vastus lateralis muscle gene expression levels of 12 women with the metabolic syndrome before and after a 6 month exercise training program RNA was isolated from a vastus lateralis muscle biopsy of 6 women with the metabolic syndrome before and after a 6 month guided endurance exercise training program
Project description:Male patients (n=6, mean age 62 years) with NYHA III-IV and an left ventricular ejection fraction of <35% despite pharmacological therapy received 35 hours of enhanced external counterpulsation (EECP) over a period of 7 weeks. Before and after treatment, lateral vastus muscle biopsies were obtained and skeletal muscle gene expression was evaluated using the Affymetrix HuGene 1.0 platform. Skeletal muscle gene expression before and after treatment with enhanced external counterpulsation for 7 weeks in 6 male patients with severe heart failure
Project description:Facioscapulohumeral dystrophy (FSHD) is caused by decreased epigenetic repression of the D4Z4 macrosatellite array and recent studies have shown that this results in the expression of low levels of the DUX4 mRNA in skeletal muscle. Several other mechanisms have been suggested for FSHD pathophysiology and it remains unknown whether DUX4 expression can account for most of the molecular changes seen in FSHD. Since DUX4 is a transcription factor, we used RNA-seq to measure gene expression in muscle cells transduced with DUX4, and in muscle cells and biopsies from control and FSHD individuals. We show that DUX4 target gene expression is the major molecular signature in FSHD muscle together with a gene expression signature consistent with an immune cell infiltration. In addition, one unaffected individual without a known FSHD-causing mutation showed expression of DUX4 target genes. This individual has a sibling with FSHD and also without a known FSHD-causing mutation, suggesting the presence of yet unidentified modifier locus for DUX4 expression and FSHD. These findings demonstrate that expression of DUX4 accounts for the majority of the gene expression changes in FSHD skeletal muscle together with an immune cell infiltration. RNA-seq for muscle cells and biopsies from control and FSHD individuals.