Effects of Dexamethasone on Satellite Cells and Tissue Engineered Skeletal Muscle Units

Syverud, Brian C; VanDusen, Keith W.; Larkin, Lisa M.

doi:10.1089/ten.tea.2015.0545

Cited by 33 publications

(46 citation statements)

References 30 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…A key finding of our study was that supplementing the culture media of engineered skeletal muscle constructs with leucine for the final 5 days of experimentation augmented maximal contractile force by up to ∼80%. Indeed, while other investigations have observed an augmented functionality of engineered muscles following chronic treatment with pharmacological agents (Madden, Juhas, Kraus, Truskey, & Bursac, 2015;Syverud, VanDusen, & Larkin, 2016;Weist et al, 2013), this represents the first report of how amino acids can enhance skeletal muscle contractile function in vitro, thus providing novel data regarding leucine's anabolic properties. Furthermore, the present data show that the enhancement in maximal force production in the presence of leucine was not dose-dependent, which is in contrast to our findings for signaling through mTORC1 and myotube size, and perhaps suggests that the additional muscle growth at higher leucine doses is partially a result of accretion of non-contractile proteins.…”

Section: Enhanced Contractile Force With Leucine Supplementation Ismentioning

confidence: 74%

Leucine elicits myotube hypertrophy and enhances maximal contractile force in tissue engineered skeletal muscle in vitro

Martin

Turner

Farrington

et al. 2017

Journal Cellular Physiology

View full text Add to dashboard Cite

The amino acid leucine is thought to be important for skeletal muscle growth by virtue of its ability to acutely activate mTORC1 and enhance muscle protein synthesis, yet little data exist regarding its impact on skeletal muscle size and its ability to produce force. We utilized a tissue engineering approach in order to test whether supplementing culture medium with leucine could enhance mTORC1 signaling, myotube growth, and muscle function. Phosphorylation of the mTORC1 target proteins 4EBP‐1 and rpS6 and myotube hypertrophy appeared to occur in a dose dependent manner, with 5 and 20 mM of leucine inducing similar effects, which were greater than those seen with 1 mM. Maximal contractile force was also elevated with leucine supplementation; however, although this did not appear to be enhanced with increasing leucine doses, this effect was completely ablated by co‐incubation with the mTOR inhibitor rapamycin, showing that the augmented force production in the presence of leucine was mTOR sensitive. Finally, by using electrical stimulation to induce chronic (24 hr) contraction of engineered skeletal muscle constructs, we were able to show that the effects of leucine and muscle contraction are additive, since the two stimuli had cumulative effects on maximal contractile force production. These results extend our current knowledge of the efficacy of leucine as an anabolic nutritional aid showing for the first time that leucine supplementation may augment skeletal muscle functional capacity, and furthermore validates the use of engineered skeletal muscle for highly‐controlled investigations into nutritional regulation of muscle physiology.

show abstract

Section: Enhanced Contractile Force With Leucine Supplementation Ismentioning

confidence: 74%

Leucine elicits myotube hypertrophy and enhances maximal contractile force in tissue engineered skeletal muscle in vitro

Martin

Turner

Farrington

et al. 2017

Journal Cellular Physiology

View full text Add to dashboard Cite

show abstract

“…Using our established SMU fabrication protocol, muscle isolates were cultured with four DEX concentrations (0, 5, 10, and 25nM)(Syverud et al June 2015 (Submitted)). Following seeding onto a laminin-coated Sylgard substrate, the administration of DEX was initiated at seeding (Day 0), during the proliferative stage (Day 6), or in the differentiation phase (Day 9) and was sustained until the completion of SMU fabrication.…”

Section: Effects Of Dexamethasone On Satellite Cells During Skeletal mentioning

confidence: 99%

Growth Factors for Skeletal Muscle Tissue Engineering

Syverud¹,

VanDusen

Larkin³

2016

Cells Tissues Organs

Self Cite

View full text Add to dashboard Cite

Tissue-engineered skeletal muscle holds promise as a source of graft tissue for repair of volumetric muscle loss and as a model system for pharmaceutical testing. To reach this potential, engineered tissues must advance past the neonatal phenotype that characterizes the current state of the art. In this review, we describe native skeletal muscle development and identify important growth factors controlling this process. By comparing in vivo myogenesis to in vitro satellite cell cultures and tissue engineering approaches, several key similarities and differences that may potentially advance tissue-engineered skeletal muscle were identified. In particular, hepatocyte and fibroblast growth factors used to accelerate satellite cell activation and proliferation, followed by addition of insulin-like growth factor as a potent inducer of differentiation, are proven methods for increased myogenesis in engineered muscle. Additionally, we review our recent novel application of dexamethasone (DEX), a glucocorticoid that stimulates myoblast differentiation, in skeletal muscle tissue engineering. Using our established skeletal muscle unit (SMU) fabrication protocol, timing- and dose-dependent effects of DEX were measured. The supplemented SMUs demonstrated advanced sarcomeric structure and significantly increased myotube diameter and myotube fusion compared to untreated controls. Most significantly, these SMUs exhibited a fivefold rise in force production. Thus, we concluded that DEX may serve to improve myogenesis, advance muscle structure, and increase force production in engineered skeletal muscle.

show abstract

“…But then – what might be the explanation for adequate myogenic differentiation in HGF/IGF-1 free environment? First of all, our HGF/IGF-1 free medium (or control medium) contains already dexamethasone and bFGF, two factors known to influence myogenic differentiation [ 18 , 51 , 52 ]. Furthermore, as mentioned earlier, both MSC and myoblasts are known to secrete several growth factors involved in the muscle regeneration process [ 13 , 16 , 17 , 43 ].…”

Section: Discussionmentioning

confidence: 99%

Mesenchymal stem cells and myoblast differentiation under HGF and IGF-1 stimulation for 3D skeletal muscle tissue engineering

et al. 2017

View full text Add to dashboard Cite

BackgroundVolumetric muscle loss caused by trauma or after tumour surgery exceeds the natural regeneration capacity of skeletal muscle. Hence, the future goal of tissue engineering (TE) is the replacement and repair of lost muscle tissue by newly generating skeletal muscle combining different cell sources, such as myoblasts and mesenchymal stem cells (MSCs), within a three-dimensional matrix. Latest research showed that seeding skeletal muscle cells on aligned constructs enhance the formation of myotubes as well as cell alignment and may provide a further step towards the clinical application of engineered skeletal muscle.In this study the myogenic differentiation potential of MSCs upon co-cultivation with myoblasts and under stimulation with hepatocyte growth factor (HGF) and insulin-like growth factor-1 (IGF-1) was evaluated. We further analysed the behaviour of MSC-myoblast co-cultures in different 3D matrices.ResultsPrimary rat myoblasts and rat MSCs were mono- and co-cultivated for 2, 7 or 14 days. The effect of different concentrations of HGF and IGF-1 alone, as well as in combination, on myogenic differentiation was analysed using microscopy, multicolour flow cytometry and real-time PCR. Furthermore, the influence of different three-dimensional culture models, such as fibrin, fibrin-collagen-I gels and parallel aligned electrospun poly-ε-caprolacton collagen-I nanofibers, on myogenic differentiation was analysed. MSCs could be successfully differentiated into the myogenic lineage both in mono- and in co-cultures independent of HGF and IGF-1 stimulation by expressing desmin, myocyte enhancer factor 2, myosin heavy chain 2 and alpha-sarcomeric actinin. An increased expression of different myogenic key markers could be observed under HGF and IGF-1 stimulation. Even though, stimulation with HGF/IGF-1 does not seem essential for sufficient myogenic differentiation. Three-dimensional cultivation in fibrin-collagen-I gels induced higher levels of myogenic differentiation compared with two-dimensional experiments. Cultivation on poly-ε-caprolacton-collagen-I nanofibers induced parallel alignment of cells and positive expression of desmin.ConclusionsIn this study, we were able to myogenically differentiate MSC upon mono- and co-cultivation with myoblasts. The addition of HGF/IGF-1 might not be essential for achieving successful myogenic differentiation. Furthermore, with the development of a biocompatible nanofiber scaffold we established the basis for further experiments aiming at the generation of functional muscle tissue.Electronic supplementary materialThe online version of this article (doi:10.1186/s12860-017-0131-2) contains supplementary material, which is available to authorized users.

show abstract

Effects of Dexamethasone on Satellite Cells and Tissue Engineered Skeletal Muscle Units

Cited by 33 publications

References 30 publications

Leucine elicits myotube hypertrophy and enhances maximal contractile force in tissue engineered skeletal muscle in vitro

Leucine elicits myotube hypertrophy and enhances maximal contractile force in tissue engineered skeletal muscle in vitro

Growth Factors for Skeletal Muscle Tissue Engineering

Mesenchymal stem cells and myoblast differentiation under HGF and IGF-1 stimulation for 3D skeletal muscle tissue engineering

Contact Info

Product

Resources

About