Differentiation of muscle and the determination of ultimate tissue size

Penney, R.K.; Prentis, P. F.; Marshall, Phillip; Goldspink, G.

doi:10.1007/bf00204886

Cited by 23 publications

(10 citation statements)

References 30 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…A taxa de proliferação e de fusão estariam reduzidas nos animais desnutridos, mesmo que o número de mioblastos fundidos permanecesse constante para cada miotubo 32,36 . O número de miotubos secundários formados em cada músculo seria adequadamente regulado 4 , e a presença da terminação nervosa teria um papel fundamental no início da fusão de células para originar os miotubos secundários 33 .…”

Section: Discussionunclassified

Intrauterine energetic malnutrition in rats: skeletal muscle changes in the 1st and 2nd generations

Fl¹,

As²,

Schmidt³

et al. 1999

J Pediatr (Rio J)

View full text Add to dashboard Cite

ResumoObjetivo: Estudar o músculo esquelético (ME) de recém-nascidos desnutridos intra-uterinos através de biopsia muscular com estudo histoquímico.Material e Métodos: Utilizaram-se ratas Wistar EPM-1, 90 dias, peso 200 ± 20g, desnutridas durante toda gestação. No 21 o dia de gestação foi colhida biopsia do músculo biceps braquii dos recém-nascidos (RN), obtidos por cesária (1 a geração). Um grupo de RN desnutridos foi recuperado nutricionalmente após o nascimento, pela permanência de seis filhotes/rata nutriz e pela alimentação ad libitum até o 90 0 dia de vida, quando as fêmeas foram colocadas para cruzamento, originando os recém-nascidos da 2ª geração.Resultados: O ganho de peso durante a gestação e o peso do RN foram significativamente diferentes quando comparado cada grupo desnutrido ao seu respectivo grupo controle. As biopsias musculares dos RN desnutridos intra-uterinos apresentaram comprometimento como perda do predomínio de fibra tipo II, diminuição do diâmetro das fibras musculares, baixa atividade oxidativa, proliferação de tecido intersticial e edema. Na segunda geração, os recém-nascidos apresentaram peso corporal adequado, mas mantinham o comprometimento do tecido muscular como diminuição do predomínio de fibras tipo II, diminuição do diâmetro das fibras musculares, baixa atividade oxidativa, presença de aumento de espaço intersticial, aumento de necrose mas sem edema.Conclusão: A desnutrição energética na fase intra-uterina afeta diretamente o ME, podendo causar alterações irreversíveis que se repetem na geração seguinte, indicando a gravidade de a desnutrição ocorrer na fase crítica de desenvolvimento do tecido muscular. AbstractObjective: To study by histochemical analysis the skeletal muscle in malnourished newborn rats submitted to intrauterine malnutrition.Methods: 90 days old female, Wistar EPM-1 rats, with 200 ± 20g body weight, malnourished during the gestation period were studied. At the 21 th day of gestation, muscular biopsy was performed in the biceps bracchi of the newborns, obtained by cesarean (1 st generation). One group of newborn intrauterine malnourished rats had nutritional recovery after birth by staying six/lactating rat and by free feeding up to the 90 th day of life, when the females became pregnant and their offspring formed the 2 nd generation.Results: Weight gain during gestation and body weight of the newborn were significantly different when each malnourished group was compared to its respective control. The muscular biopsies of the malnourished newborns presented tissue involvement, characterized by loss of predominance of type II fibres, low oxidative activity, lessening of muscular fiber diameter, proliferation of intersticial tissue, and edema. In the 2 nd generation, the newborns presented adequate body weight, but maintained muscular tissue involvement, with lessening of predominance of type II fibers, reduction of muscular fiber diameter, low oxidative activity, increase of intersticial space, necrosis, but without edema.Conclusion: The energetic malnutrition ...

show abstract

Section: Discussionunclassified

Intrauterine energetic malnutrition in rats: skeletal muscle changes in the 1st and 2nd generations

Fl¹,

As²,

Schmidt³

et al. 1999

J Pediatr (Rio J)

View full text Add to dashboard Cite

show abstract

“…Rehfeldt et al (2000, p.183) also suggested that growth selection leads to increases in myoblast and/or satellite cell proliferation rates. Increases in the proliferation rates can be indicated by following factors: higher myonuclear numbers (e.g., Knizetova et al, 1972;Penney et al, 1983;Brown and Stickland, 1994), higher DNA synthesis rate (Knizetova et al, 1972) and higher total muscle DNA content (e.g., Knizetova et al, 1972;Martin and White, 1979;Fowler et al, 1980;Campion et al, 1982;Jones et al, 1986;Mitchell and Burke, 1995). The greater expression of SCD gene transcripts in the muscle of SO lambs in relation to the MO lambs suggests a higher activity of this enzyme in SO animals.…”

Section: The Expression Of Transcripts Involved With Growth Skeletalmentioning

confidence: 97%

Differentially transcribed genes in skeletal muscle of lambs

et al. 2012

View full text Add to dashboard Cite

a b s t r a c tThe objective of this study was to compare gene transcription profiles in Longissimus dorsi muscle of the following four hair sheep genetic groups, Morada Nova (MO), Brazilian Somali (SO), Santa Inês (SI) and ½Dorper Â ½Morada Nova (F1). These groups all display different postnatal muscle growth. The transcriptomes of the skeletal muscle of the lambs (at 200 days of age) were profiled by using oligonucleotide microarrays and reverse transcriptionquantitative real-time PCR (RT-qPCR). The microarray experiment identified 262 transcripts that were differentially expressed when transcription levels were compared between the different breeds. A total of 23 transcripts among which those involved in skeletal muscle development (MyoD1 and IGFBP4), lipogenesis and adipogenesis (C/EBPd, PPARg and PGDS) were differentially expressed in at least in one comparison. Clustering analysis showed that there is greater similarity in gene expression between the MO and SI breeds and between F1 and SO genetic groups. The SO breed has the most distinct expression pattern. The RT-qPCR results confirmed the findings from the microarray study. A positive correlation was observed between the expression of MyoD1 and the cold carcass yield. The negative correlations between the weight and yield of cold carcass with the expression of C/EBPd mean that the selection for adipogenesis could lead to a lower carcass weight. The GLUT3 and PYGL gene transcripts were negatively correlated with fat thickness, but ATP5G1 was positively correlated with this trait. Interestingly, many genes negatively correlated with PUFA were positively correlated with cold carcass yield. In conclusion, the present work demonstrated that there are breed-specific expression patterns in Brazilian hair sheep genetic groups. The differences in gene expression among genetic groups were consistent with their phenotypic differences. The positive correlation of the MyoD1 expression with the cold carcass yield suggests that this gene is important for tissue growth in sheep. The positive correlation of the C/EBPd expression with PUFA provides an opportunity to select for lipid deposition in meat animals.

show abstract

“…However, our discovery of myocyte death in branchial muscles argues against this hypothesis. Artificial selection for increased muscle mass and high hatching success in domestic birds can lead to increased muscle fiber number (Luff and Goldspink, 1967;Penny et al, 1983). Without a concomitant increase in the size of the motor neuron pool many of these additional muscle cells could suffer the fate we witnessed.…”

Section: Functional Significancementioning

confidence: 99%

Muscle cell death during the development of head and neck muscles in the chick embryo

McClearn

Medville

Noden

1995

Developmental Dynamics

View full text Add to dashboard Cite

Degenerating myofibers have been reported in the embryos and neonates of a number of birds and mammals, but neither the pervasiveness of the phenomenon nor the spatiotemporal patterns of degeneration has been examined in detail. Using transmission electron microscopy, we determined the patterns of muscle cell death in the chick biventer cervicis, a head extensor muscle. Cell death is most pronounced at incubation days 10 through 15, and occurs throughout the muscle. This is the period during which many myofiber clusters segregate into individual fibers, each with a separate basal lamina, and secondary myofibers become demarcated. Cells of largest diameter, presumably the primary myofibers, are preferentially affected. Degenerating cells exhibit a cohort of cytological features consistent with apoptosis, including the presence of dense, darkly-staining, hypercontracted myofibrils, misshapen nuclei with irregular chromatin condensations along the nuclear envelope, and scores of cytoplasmic vesicles and vacuoles. In cross section some large diameter muscle cells are characterized by sparse, flocculent cytoplasm that is devoid of myofibrils and organelles. Some show disintegrating cell membranes. In longitudinal section 200-300 pm long regions of hypercontracted myofibrils alternate with areas devoid of fibrils; this arrangement suggests that the myofibrils break into segments that are in register along one part of a muscle fiber and entirely absent from the adjacent length of fiber. We have observed similar patterns of muscle cell degeneration in the complexus, splenius cervicis, depressor mandibulae, and branchiomandibularis muscles. By day 18 of incubation most signs of degeneration are absent and by hatching (day 21) the muscle fibers all appear healthy. Many of these cytological changes in embryonic head muscle cells are characteristic of programmed cell death. We hypothesize that large-scale death of myocytes is a normal part of avian myogenesis and an important mechanism for affecting the transformation from embryonic to hatching muscle patterning. o 1995 Wiley-Liss, Inc.

show abstract

Differentiation of muscle and the determination of ultimate tissue size

Cited by 23 publications

References 30 publications

Intrauterine energetic malnutrition in rats: skeletal muscle changes in the 1st and 2nd generations

Intrauterine energetic malnutrition in rats: skeletal muscle changes in the 1st and 2nd generations

Differentially transcribed genes in skeletal muscle of lambs

Muscle cell death during the development of head and neck muscles in the chick embryo

Contact Info

Product

Resources

About