Home About us Contact
|
Home About us Contact | ||
|
|
||
Skeletal Muscle Tissue (skeletal + muscle_tissue)
Selected AbstractsExpression of the ,-adhesin part of HRgpA in Sprague Dawley rats induces a specific antibody responseMOLECULAR ORAL MICROBIOLOGY, Issue 2 2004K. S. Vĺgnes The ,-adhesin part of the Porphyromonas gingivalis W50 (ATCC 53978) protease HRgpA was cloned in an eukaryotic expression vector and expressed in COS-7 cells. The monoclonal antibody MAb (61BG1.3), specific for the hemagglutinating domain of ,-adhesin, recognized the expressed ,-adhesin in the transfected cells both by immunoblot and immunofluorescence. Sprague Dawley rats were immunized intramuscularly with ,-adhesin encoding expression plasmid and expression plasmid without ,-adhesin insert. Skeletal muscle tissue at the site of immunization in the ,-adhesin immunized animals was shown to express this protein. The immunization induced a ,-adhesin-specific antibody response. Sera from the immunized animals were tested for hemagglutination inhibiting activity. Due to high natural inhibiting activity in all rat sera tested, no increased hemagglutination inhibition was detected in sera from the ,-adhesin immunized animals. [source] NDRG2, a novel regulator of myoblast proliferation, is regulated by anabolic and catabolic factorsTHE JOURNAL OF PHYSIOLOGY, Issue 7 2009Victoria C. Foletta Skeletal muscle tissue undergoes adaptive changes in response to stress and the genes that control these processes are incompletely characterised. NDRG2 (N-myc downstream-regulated gene 2), a stress- and growth-related gene, was investigated in skeletal muscle growth and adaption. While NDRG2 expression levels were found to be up-regulated in both differentiated human and mouse myotubes compared with undifferentiated myoblasts, the suppression of NDRG2 in C2C12 myoblasts resulted in slowed myoblast proliferation. The increased expression levels of the cell cycle inhibitors, p21 Waf1/Cip1 and p27 Kip1, and of various muscle differentiation markers in NDRG2-deficient myoblasts indicate that a lack of NDRG2 promoted cell cycle exiting and the onset of myogenesis. Furthermore, the analysis of NDRG2 regulation in C2C12 myotubes treated with catabolic and anabolic agents and in skeletal muscle from human subjects following resistance exercise training revealed NDRG2 gene expression to be down-regulated during hypertrophic conditions, and conversely, up-regulated during muscle atrophy. Together, these data demonstrate that NDRG2 expression is highly responsive to different stress conditions in skeletal muscle and suggest that the level of NDRG2 expression may be critical to myoblast growth and differentiation. [source] Oestrogen receptor , is expressed in adult human skeletal muscle both at the mRNA and protein levelACTA PHYSIOLOGICA, Issue 4 2003A. Wiik Abstract Aim:, There are two known oestrogen receptors (ER), oestrogen receptor , (ER,) and the recently cloned oestrogen receptor , (ER,). ER, mRNA has been detected in mouse, rat, bovine and human skeletal muscle. ER, mRNA has been detected in bovine skeletal muscle. To our knowledge, no study has investigated the expression of oestrogen receptor , in human skeletal muscle. Therefore, the primary aim of the present investigation was to study ER, mRNA and protein expression in human skeletal muscle. In addition the ER, expression was also studied. Methods:, Muscle biopsies were taken from vastus lateralis in six healthy adults (three women and three men). mRNA expression was detected with real-time PCR (TaqMan) and protein localization by immunohistochemistry. Results:, A clear expression of ER, and ER, mRNA was seen in skeletal muscle in all subjects. The ER, mRNA expression was 180 fold higher compared with that of ER, mRNA. Immunohistochemistry demonstrated positive staining for ER,, but not for ER,, with localization to the nuclei of skeletal muscle fibres. On average, 70% of all nuclei were ER, -positive. Conclusion:, The present study shows for the first time ER, mRNA and protein expression in human skeletal muscle tissue in both males and females. [source] Expression and alternative splicing of N-RAP during mouse skeletal muscle development,CYTOSKELETON, Issue 12 2008Shajia Lu Abstract N-RAP alternative splicing and protein localization were studied in developing skeletal muscle tissue from pre- and postnatal mice and in fusing primary myotubes in culture. Messages encoding N-RAP-s and N-RAP-c, the predominant isoforms of N-RAP detected in adult skeletal muscle and heart, respectively, were present in a 5:1 ratio in skeletal muscle isolated from E16.5 embryos. N-RAP-s mRNA levels increased three-fold over the first 3 weeks of postnatal development, while N-RAP-c mRNA levels remained low. N-RAP alternative splicing during myotube differentiation in culture was similar to the pattern observed in embryonic and neonatal muscle, with N-RAP-s expression increasing and N-RAP-c mRNA levels remaining low. In both developing skeletal muscle and cultured myotubes, N-RAP protein was primarily associated with developing myofibrillar structures containing ,-actinin, but was not present in mature myofibrils. The results establish that N-RAP-s is the predominant spliced form of N-RAP present throughout skeletal muscle development. Cell Motil. Cytoskeleton 2008. Published 2008 Wiley-Liss, Inc. [source] Cell surface nucleolin on developing muscle is a potential ligand for the axonal receptor protein tyrosine phosphatase-,FEBS JOURNAL, Issue 20 2006Daniel E. Alete Reversible tyrosine phosphorylation, catalyzed by receptor tyrosine kinases and receptor tyrosine phosphatases, plays an essential part in cell signaling during axonal development. Receptor protein tyrosine phosphatase-, has been implicated in the growth, guidance and repair of retinal axons. This phosphatase has also been implicated in motor axon growth and innervation. Insect orthologs of receptor protein tyrosine phosphatase-, are also implicated in the recognition of muscle target cells. A potential extracellular ligand for vertebrate receptor protein tyrosine phosphatase-, has been previously localized in developing skeletal muscle. The identity of this muscle ligand is currently unknown, but it appears to be unrelated to the heparan sulfate ligands of receptor protein tyrosine phosphatase-,. In this study, we have used affinity chromatography and tandem MS to identify nucleolin as a binding partner for receptor protein tyrosine phosphatase-, in skeletal muscle tissue. Nucleolin, both from tissue lysates and in purified form, binds to receptor protein tyrosine phosphatase-, ectodomains. Its expression pattern also overlaps with that of the receptor protein tyrosine phosphatase-,-binding partner previously localized in muscle, and nucleolin can also be found in retinal basement membranes. We demonstrate that a significant amount of muscle-associated nucleolin is present on the cell surface of developing myotubes, and that two nucleolin-binding components, lactoferrin and the HB-19 peptide, can block the interaction of receptor protein tyrosine phosphatase-, ectodomains with muscle and retinal basement membranes in tissue sections. These data suggest that muscle cell surface-associated nucleolin represents at least part of the muscle binding site for axonal receptor protein tyrosine phosphatase-, and that nucleolin may also be a necessary component of basement membrane binding sites of receptor protein tyrosine phosphatase-,. [source] Changes in amino acid composition in the tissues of African catfish (Clarias gariepinus) as a consequence of dietary L-carnitine supplementsJOURNAL OF APPLIED ICHTHYOLOGY, Issue 3 2002R. O. A. Ozório A study was undertaken to examine the effect of different amounts of dietary lysine (13 and 21 g kg,1 diet), lipid (80 and 160 g kg,1 diet) and L -carnitine (0.2 and 1.0 g kg,1 diet) on growth performance, proximate composition and amino acid metabolism of the African catfish (Clarias gariepinus). Juvenile African catfish (23 ± 1.5 g/fish) were stocked into 70-L aquaria (16 aquaria, 28 fish/aquarium) connected to a recirculation system during a maximum period of 74 days. All groups were fed at a level of 24 g kg,0.8 day,1 in an experiment run at pair feeding. Animals receiving 1.0 g carnitine accumulated up to six times more carnitine in their tissues than animals receiving 0.2 g (P < 0.05). Acyl-carnitine and free L -carnitine levels increased in the whole body and in tissues. Dietary L -carnitine supplements increased protein-to-fat ratios in the body, but did not affect growth rate. Protein-to-fat ratios were only affected when the biosynthesis capacity of L -carnitine was restricted due to low lysine levels and when there was a shortage of dietary fat. When lysine was offered at 21 g kg,1 feed, dietary L -carnitine supplements did not affect the amino acid concentrations of body tissues. Dietary L -carnitine supplements raised the concentration of glutamic acid,>,aspartic acid,>,glycine > alanine > arginine > serine > threonine in skeletal muscle tissue (P < 0.05). Total amino acid concentration in muscle and liver tissues (dry-matter basis) increased from 506 to 564 and from 138 to 166 mg g,1, respectively, when diets were offered with high L -carnitine, low lysine and low fat levels. These data suggest that dietary L -carnitine supplementation may increase fatty acid oxidation and possibly decrease amino acid combustion for energy. [source] Vitamin D Receptor Expression in Human Muscle Tissue Decreases With Age,JOURNAL OF BONE AND MINERAL RESEARCH, Issue 2 2004HA Bischoff-Ferrari Abstract Intracellular 1,25-dihydroxyvitamin D receptor (VDR) is expressed in human skeletal muscle tissue. However, it is unknown whether VDR expression in vivo is related to age or vitamin D status, or whether VDR expression differs between skeletal muscle groups. Introduction: We investigated these factors and their relation to 1,25-dihydroxyvitamin D receptor (VDR) expression in freshly removed human muscle tissue. Materials and Methods: We investigated biopsy specimens of the gluteus medius taken at surgery from 20 female patients undergoing total hip arthroplasty (mean age, 71.6 ± 14.5; 72% > 65 years) and biopsy specimens of the transversospinalis muscle taken at surgery from 12 female patients with spinal operations (mean age, 55.2 ± 19.6; 28% > 65 years). The specimens were obtained by immunohistological staining of the VDR using a monoclonal rat antibody to the VDR (Clone no. 9A7). Quantitative VDR expression (number of VDR positive nuclei) was assessed by counting 500 nuclei per specimen and person. Serum concentrations of 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D were assessed at day of admission to surgery. Results: All muscle biopsy specimens stained positive for VDR. In the univariate analyses, increased age was associated with decreased VDR expression (r = 0.5: p = 0.004), whereas there were no significant correlations between VDR expression and 25-hydroxyvitamin D or 1,25-dihydroxyvitamin D levels. VDR expression did not differ between patients with hip and spinal surgery. In the multivariate analysis, older age was a significant predictor of decreased VDR expression after controlling biopsy location (gluteus medius or the transversospinalis muscle), and 25-hydroxyvitamin D levels (linear regression analysis: ,-estimate = ,2.56; p = 0.047). Conclusions: Intranuclear immunostaining of the VDR was present in muscle biopsy specimens of all orthopedic patients. Older age was significantly associated with decreased VDR expression, independent of biopsy location and serum 25-hydroxyvitamin D levels. [source] Skeletal muscle tissue engineeringJOURNAL OF CELLULAR AND MOLECULAR MEDICINE, Issue 4 2004A. D. Bach Abstract The reconstruction of skeletal muscle tissue either lost by traumatic injury or tumor ablation or functional damage due to myopathies is hampered by the lack of availability of functional substitution of this native tissue. Until now, only few alternatives exist to provide functional restoration of damaged muscle tissues. Loss of muscle mass and their function can surgically managed in part using a variety of muscle transplantation or transposition techniques. These techniques represent a limited degree of success in attempts to restore the normal functioning, however they are not perfect solutions. A new alternative approach to addresssing difficult tissue reconstruction is to engineer new tissues. Although those tissue engineering techniques attempting regeneration of human tissues and organs have recently entered into clinical practice, the engineering of skletal muscle tissue ist still a scientific challenge. This article reviews some of the recent findings resulting from tissue engineering science related to the attempt of creation and regeneration of functional skeletal muscle tissue. [source] Recent advances in adaptive thermogenesis: potential implications for the treatment of obesityOBESITY REVIEWS, Issue 2 2009S. L. J. Wijers Summary Large inter-individual differences in cold-induced (non-shivering) and diet-induced adaptive thermogenesis exist in animals and humans. These differences in energy expenditure can have a large impact on long-term energy balance and thus body weight (when other factors remain stable). Therefore, the level of adaptive thermogenesis might relate to the susceptibility to obesity; efforts to increase adaptive thermogenesis might be used to treat obesity. In small mammals, the main process involved is mitochondrial uncoupling in brown adipose tissue (BAT), which is regulated by the sympathetic nervous system. For a long time, it was assumed that mitochondrial uncoupling is not a major physiological contributor to adaptive thermogenesis in adult humans. However, several studies conducted in recent years suggest that mitochondrial uncoupling in BAT and skeletal muscle tissue in adult humans can be physiologically significant. Other mechanisms besides mitochondrial uncoupling that might be involved are futile calcium cycling, protein turnover and substrate cycling. In conjunction with recent advances on signal transduction studies, this knowledge makes manipulation of adaptive thermogenesis a more realistic option and thus a pharmacologically interesting target to treat obesity. [source] Isolation of porcine expressed sequence tags for the construction of a first genomic transcript map of the skeletal muscle in pigANIMAL GENETICS, Issue 1 2002R. Davoli To identify genes with effects on meat quality and production traits we developed an adult porcine skeletal muscle cDNA library. After pre-screening this library with seven genes highly expressed in skeletal muscle, 385 non-hybridizing clones were sequenced from both ends to yield 510 expressed sequence tags (ESTs). Together with those ESTs previously generated from this library, we have produced 701 porcine skeletal muscle ESTs. These ESTs were grouped into 306 different cDNA species and compared with the human skeletal muscle transcriptional profiles obtained from different databases. Furthermore we mapped 107 of these cDNAs using a somatic cell hybrid panel with genes mapping over all the autosomes (except on chromosome 11) and on chromosome X. The mapping of these cDNAs contributed to the construction of a first genomic transcript map of the skeletal muscle tissue in pig. [source] Identifications of expressed sequence tags from Pacific threadfin (Polydactylus sexfilis) skeletal muscle cDNA libraryAQUACULTURE RESEARCH, Issue 4 2010Shizu Watanabe Abstract Pacific threadfin (Polydactylus sexfilis), locally known as Moi, is a desirable fish for aquaculture and recreational fishing. To understand the basic mechanism of muscle formation and its impacts on flesh quality, we established a cDNA library using mRNA of the skeletal muscle tissue from fingerlings. The library size was 1.1 × 108 plaque forming units mg,1 and the percentage of recombinant clones was >81%. A pilot sequencing project from 181 clones identified 129 useful expressed sequence tags (ESTs), of which 90 ESTs exhibited significant homology to known genes and 39 ESTs have low homologies to unknown genes by blast algorithm. The most abundant EST from the pilot sequence data is nikotinamide riboside kinase 2 (59 times), followed by 60S ribosomal protein L24 (12 times) and ribosomal protein L8 (5 times). Fourteen novel genes were retrieved from the sequenced clones and subjected to gene ontology annotation. Four mRNA sequences were identified as significant regulators of transcription, including Not2p, Tsc22 domain family 2, LIM domain binding factor 3 and mesenchyme homeobox 2. These results suggest that the muscle cDNA library is an useful source for identifying EST sequences of Pacific threadfin. [source] Fabrication of skeletal muscle constructs by topographic activation of cell alignmentBIOTECHNOLOGY & BIOENGINEERING, Issue 2 2009Yi Zhao Abstract Skeletal muscle fiber construction for tissue-engineered grafts requires assembly of unidirectionally aligned juxtaposed myotubes. To construct such a tissue, a polymer microchip with linearly aligned microgrooves was fabricated that could direct myoblast adaptation under stringent conditions. The closely spaced microgrooves fabricated by a modified replica molding process guided linear cellular alignment. Examination of the myoblasts by immunofluorescence microscopy demonstrated that the microgrooves with subcellular widths and appropriate height-to-width ratios were required for practically complete linear alignment of myoblasts. The topology-dependent cell alignment encouraged differentiation of myoblasts into multinucleate, myosin heavy chain positive myotubes. The monolayer of myotubes formed on the microstructured chips allowed attachment, growth and differentiation of subsequent layers of linearly arranged myoblasts, parallel to the primary monolayer of myotubes. The consequent deposition of additional myoblasts on the previous layer of myotubes resulted in three-dimensional multi-layered structures of myotubes, typical of differentiated skeletal muscle tissue. The findings demonstrate that the on-chip device holds promise for providing an efficient means for guided muscle tissue construction. Biotechnol. Bioeng. 2009;102: 624,631. © 2008 Wiley Periodicals, Inc. [source] FT-IR spectroscopy in diagnosis of diabetes in rat animal modelJOURNAL OF BIOPHOTONICS, Issue 8-9 2010Feride Severcan Abstract In recent years, Fourier Transform Infrared (FT-IR) spectroscopy has had an increasingly important role in the field of pathology and diagnosis of disease states. In the current study, FT-IR spectroscopy together with cluster analysis were used as a diagnostic tool in the discrimination of diabetic samples from control ones in rat kidney plasma membrane apical sides (brush-border membranes), liver microsomal membranes and Extensor digitorum longus (EDL) and Soleus (SOL) skeletal muscle tissues. A variety of alterations in the spectral parameters, such as frequency and signal intensity/area was observed in diabetic tissues and membranes compared to the control samples. Based on these spectral variations, using cluster analysis successful differentiation between diabetic and control groups was obtained in different spectral regions. The results of this current study further revealed the power and sensitivity of FT-IR spectroscopy in precise and automated diagnosis of diabetes. (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] MicroRNA expression profiles of porcine skeletal muscleANIMAL GENETICS, Issue 5 2010B. Zhou Summary MicroRNAs (miRNAs) are endogenous non-coding RNAs of ,22 nucleotides in length that play important roles in multiple biological processes by degrading targeted mRNAs or repressing mRNA translation. To evaluate the roles of miRNA in porcine skeletal muscle, miRNA expression profiles were investigated using longissimus muscle tissue from pigs at embryonic day 90 (E90) and postpartum day 120 (PD120). First, we used previously known miRNA sequences from humans and mice to perform blast searches against the porcine expressed sequence tag (EST) database; 98 new miRNA candidates were identified according to a range of filtering criteria. These miRNA candidates and 73 known miRNAs (miRBase 13.0) from pigs were chosen for porcine miRNA microarray analysis. A total of 16 newly identified miRNAs and 31 previously known miRNAs were detected in porcine skeletal muscle tissues. During later foetal development at E90, miR-1826, miR-26a, miR-199b and let-7 were highly expressed, whilst miR-1a, miR-133a, miR-26a and miR-1826 showed highest abundance during the fast growing stage at PD120. Using the 47 miRNAs detected by the microarray assay, we performed further investigations using the publicly available porcine mRNA database from NCBI and computed potential target hits using the software rnahybrid. This study identified 16 new miRNA candidates, computed potential target hits for 18 miRNA families and determined the miRNA expression profiles in porcine skeletal muscle tissues at different developmental stages. These results provide a valuable resource for investigators interested in post-transcriptional gene regulation in pigs and related animals. [source] | ||||||||||||||||