Developmental programming of skeletal muscle phenotype/metabolism

Abstract

Skeletal muscle is a highly dynamic and malleable tissue that is able to adapt to different stimuli placed upon it, both during gestation and after birth, ultimately resulting in anatomical changes to muscle fibre composition. Variation in nutrient supply throughout gestation is common, whether in livestock or in the human. The specific effects of maternal nutrition on foetal development are at the forefront of scientific research. However, results describing how different maternal feeding strategies affect skeletal muscle fibre development in the offspring are not fully consistent, even where the same time windows during gestation have been examined. The aim of this study is to determine the effects of increased maternal nutrition (above the recommended levels) on the Musculus semitendinosus phenotype of progeny. In all, 24 pregnant sows were assigned to one of four feeding regimes during gestation; T1 (control group): 30 MJ digestible energy per day (MJ DE/day) throughout gestation, T2: same as that for T1 but increased to 60 MJ DE/day from 25 to 50 days of gestation (dg), T3: same as that for T1 but increased to 60 MJ DE/day from 50 to 80 dg, T4: same as that for T1 but increased nutrition to 60 MJ DE/day from 25 to 80 dg. Light-and heavy-weight littermate pairs of the same sex were selected at birth and individually fed to slaughter (c. 158 days). Histochemical and immunohistochemical staining were used to identify the predominantly oxidative (deep) and less oxidative (superficial) regions of the M. semitendinosus, and to determine total fibre number and proportions of fibre types. The results demonstrate that increased maternal nutrition alters skeletal muscle phenotype in the offspring by changing fibre-type proportions, leading to an increased oxidative capacity due to an increase in Type IIA fibres. No change in total muscle area, total muscle fibre number, or fibre cross-sectional area is observed. The precise molecular mechanism(s) by which these findings occur is being investigated.

Nutritional intervention during gestation alters growth, body composition and gene expression patterns in skeletal muscle of pig offspring

“…Furthermore, histological analysis of pigs from this trial revealed that increased maternal feeding in mid gestation improves the oxidative capacity of muscle (Markham et al, 2009). Indeed, a larger number of smaller or oxidative fibres can produce more favourable meat quality traits (more intense colour, optimum ultimate pH, less drip loss and improved tenderness of meat; Lengerken et al, 1997;Chang et al, 2003).…”

“…The animal trial was conducted at the Teagasc, Pig Development Unit, Animal & Grassland Research & Innovation Centre, Moorepark, Fermoy, Co. Cork, Ireland and is described previously by Markham et al (2009). In this trial, 64 multiparous Landrace 3 Large White sows were artificially inseminated using pooled semen from seven Hylean Large White boars (Hermitage AI, Co. Kilkenny, Ireland).…”

“…Ingredient composition and chemical analysis of the gestation and lactation diets are described by Markham et al (2009).…”

“…To follow on from Markham et al (2009) observations, this study primarily investigates the transcription of a panel of genes expressed in offspring skeletal muscle, to determine whether changes in the expression of these genes could contribute to phenotypes (growth rate, carcass quality and meat quality).…”

Endocrine and metabolic regulation of muscle growth and body composition in cattle

“…In addition, it was shown by Stickland's group that maternal nutrition can have a significant influence on muscle characteristics (Karunaratne et al, 2005). Increased maternal nutrition also induces a shift in muscle oxidative metabolism at the expense of glycolytic metabolism within the porcine offspring's muscles (Markham et al, 2009). These effects correlate with postnatal consequences for muscle growth and adiposity.…”