Skeletal Muscle Growth In Mammals Research Articles

Myostatin's marvels: From muscle regulator to diverse implications in health and disease.

Myostatin, a member of the transforming growth factor-β superfamily, is a pivotal regulator of skeletal muscle growth in mammals. Its discovery has sparked significant interest due to its multifaceted roles in various physiological processes and its potential therapeutic implications. This review explores the diverse functions of myostatin in skeletal muscle development, maintenanceand pathology. We delve into its regulatory mechanisms, including its interaction with other signalling pathways and its modulation by various factors such as microRNAs and mechanical loading. Furthermore, we discuss the therapeutic strategies aimed at targeting myostatin for the treatment of muscle-related disorders, including cachexia, muscular dystrophyand heart failure. Additionally, we examine the impact of myostatin deficiency on craniofacial morphology and bone development, shedding light on its broader implications beyond muscle biology. Through a comprehensive analysis of the literature, this review underscores the importance of further research into myostatin's intricate roles and therapeutic potential in human health and disease.

The genetic diversity analysis in the donkey myostatin gene

Myostatin (MSTN) gene negatively controls skeletal muscle development and growth, variations of which play an important role in the regulation of skeletal muscle growth in mammals. However, study on genetic polymorphism ofMSTN gene in donkey is limited. In this study, we screened the single nucleotide polymorphsims (SNPs) ofMSTN gene in 13 Chinese donkey breeds. Four novel SNPs (g.229T>C, g.872A>G, g.2014G>A, and g.2395C>G) were detected and genotyped by sequencing and polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) methods. Six haplotypes (H1-H6) were analyzed, which indicated abundant haplotype diversities in Chinese donkeys. The haplotype H1 was the most dominant and ancient in all breeds. Xinjiang donkey displayed the highest haplotype diversity. The Neighbour-Joining (NJ) tree ofMSTN gene among different species was constructed. The clustering result of nine species was consistent with the fact of species differentiation. Our results will provide a reliable theoretical basis for the preservation, exploration and utilization of Chinese donkey genetic resources.

MicroRNA expression patterns in post-natal mouse skeletal muscle development

BackgroundMiRNAs are essential regulators of skeletal muscle development and homeostasis. To date, the role and regulation of miRNAs in myogenesis have been mostly studied in tissue culture and during embryogenesis. However, little information relating to miRNA regulation during early post-natal skeletal muscle growth in mammals is available. Using a high-throughput miRNA qPCR-based array, followed by stringent statistical and bioinformatics analysis, we describe the expression pattern and putative role of 768 miRNAs in the quadriceps muscle of mice aged 2 days, 2 weeks, 4 weeks and 12 weeks.ResultsForty-six percent of all measured miRNAs were expressed in mouse quadriceps muscle during the first 12 weeks of life. We report unprecedented changes in miRNA expression levels over time. The expression of a majority of miRNAs significantly decreased with post-natal muscle maturation in vivo. MiRNA clustering identified 2 subsets of miRNAs that are potentially involved in cell proliferation and differentiation, mainly via the regulation of non-muscle specific targets.ConclusionCollective miRNA expression in mouse quadriceps muscle is subjected to substantial levels of regulation during the first 12 weeks of age. This study identified a new suite of highly conserved miRNAs that are predicted to influence early muscle development. As such it provides novel knowledge pertaining to post-natal myogenesis and muscle regeneration in mammals.

Sequence Analysis and Phylogenetic Relationship of Myostatin Gene of Bikaneri Camel (Camelus dromedarius)

The draught potential of the Bikaneri camel depends on the gene affecting the muscular growth. Myostatin (MSTN) or growth and differentiation factor (GDF8) gene is the major regulator of myogenesis and skeletal muscle growth in mammals. Genomic DNA was isolated from whole blood of randomly selected Bikaneri camels (n=6) through spin column method. The MSTN exon-2 region of 375 bp was amplified using primers designed from homologous regions of MSTN gene sequence (GenBank accession number. DQ167575). The PCR amplified fragments of all the animals were sequenced through Sanger dideoxy chain termination method. The sequence of MSTN exon-2 gene was submitted to NCBI GenBank database to which an accession number KX863740 was assigned. A Neighborhood Joining (NJ) phylogenetic tree was constructed based on the lowest Bayesian Information Content (BIC) value. Sequence comparison of MSTN exon-2 gene of Bikaneri camel with homologous regions of goat, sheep, Algerian camel, buffalo, horse and pig revealed more than 95% homology. The sequence information generated for MSTN gene of Bikaneri camel would help in better understanding of growth traits and could support in conservation of dwindling camel population in Rajasthan.

ASSOCIATION BETWEEN A31GSNP OF THE MYOSTATIN GENE AND SERUM LEVELS OF ALP, GOT, P AND CA IN EGYPTIAN BUFFALO (BUBALUS BUBALIS)

Myostatin, a member of the transforming growth factor s (TGF-s) superfamily, is a negative regulator of skeletal muscle growth in mammals. The loss or inhibition of myostatin signaling dramatically increases muscle mass. This study is aimed to detect single nucleotide polymorphisms (SNPs) in the myostatin (Mstn) gene and to associate measure their effect on mineral (Ca and P) and enzymatic (GOT and ALP) serum levels in high and low meat producing Egyptian buffaloes. Mstn gene was amplified by PCR and subsequently, subjected to sequence analysis to identify different allelic patterns. The nucleotide sequence analyses revealed presence of a novel A31GSNP in Mstn1 locus at nucleotide number 50 before exon2. This SNP was synonymous as it is located in the non coding sequence and so no amino acid was changed. However, the sequences of the other three loci showed 100% identity among the Egyptian buffaloes and as compare to the published sequences of buffalo (GenBank accession number, DQ091762). To identify whether A31G SNP is accompanied by change in serum levels of GOT, ALP enzymes, and Ca and Ph, the levels of these enzymes and minerals were estimated in the serum of high and low meat producing Egyptian buffaloes at age of 2 year. The serum levels of ALP, GOT, P, and Ca were significantly increased in high meat producing buffaloes as compared to low meat producing animals. The results of this study can be enable breeders to do an accurate and earlier selection of high meat producing buffaloes on a genotype basis.

Seasonal Variation of Myostatin Gene Expression in Pectoralis Muscle of House Sparrows (Passer domesticus) Is Consistent with a Role in Regulating Thermogenic Capacity and Cold Tolerance

Winter acclimatization in small birds overwintering in cold climates, including house sparrows (Passer domesticus), is associated with improved cold tolerance, elevated summit metabolic rates (M(sum) = maximum cold-induced metabolic rate), and increased pectoralis muscle mass compared to summer birds. Myostatin is a potent autocrine/paracrine inhibitor of skeletal muscle growth in mammals and birds and is a potential candidate for regulation of seasonal phenotypic flexibility in birds. As a first step toward examining such a role for myostatin in small birds, we measured summer and winter gene expression of myostatin and its potential metalloproteinase activators TLL-1 and TLL-2 in house sparrows from southeastern South Dakota. Gene expression of myostatin decreased significantly in winter, with summer values exceeding winter values by 1.52-fold. Moreover, gene expression of TLL-1 was also significantly reduced in winter, with summer values exceeding winter values by 1.55-fold. These data are consistent with the hypothesis that the winter increases in pectoralis muscle mass, M(sum), and cold tolerance in house sparrows are mediated by reduced levels of myostatin and its activator TLL-1, and they suggest the possibility that myostatin may be a common mediator of phenotypic flexibility of muscle mass in birds.

Two myostatin genes are differentially expressed in myotomal muscles of the trout (Oncorhynchus mykiss).

Myostatin (GDF8) has been shown to be a major genetic determinant of skeletal muscle growth in mammals. In this study, we report the cloning of two trout cDNAs that encode two distinct myostatin-related proteins. The presence in this fish species of two myostatin genes (Tmyostatin 1 and Tmyostatin 2) probably results from the recent tetraploïdisation of the salmonid genome. A comparative reverse-transcriptase-linked polymerase chain reaction assay revealed that Tmyostatin 1 mRNA was present ubiquitously in trout tissues, while Tmyostatin 2 mRNA expression was restricted to muscle and brain. In developing muscle, Tmyostatin 1 expression was observed in eyed-stage embryos well before hatching, whereas Tmyostatin 2 was expressed only in free-swimming larvae. In myotomal muscle from adult animals, Tmyostatin 1 mRNA accumulation was similar in both slow- and fast-twitch fibres, and its concentration did not change during the muscle wasting associated with sexual maturation. In contrast, Tmyostatin 2 mRNA accumulated predominantly in slow-twitch fibres, and its concentration decreased dramatically in wasting muscles from maturing animals. This work shows that two distinct myostatin genes are present in the trout genome. Furthermore, it indicates that these two trout myostatin genes (i) exhibit a distinct expression pattern in muscle and non-muscle tissues and (ii) are not upregulated during the muscle wasting that accompanies sexual maturation.