Dysregulation of metabolic-associated pathways in muscle of breast cancer patients: preclinical evaluation of interleukin-15 targeting fatigue

Background Breast cancer patients report a perception of increased muscle fatigue, which can persist following surgery and standardized therapies. In a clinical experiment, we tested the hypothesis that pathways regulating skeletal muscle fatigue are down-regulated in skeletal muscle of breast cancer patients and that different muscle gene expression patterns exist between breast tumour subtypes. In a preclinical study, we tested the hypothesis that mammary tumour growth in mice induces skeletal muscle fatigue and that overexpression of the cytokine interleukin-15 (IL-15) can attenuate mammary tumourinduced muscle fatigue. Methods Early stage non-metastatic female breast cancer patients (n = 14) and female non-cancer patients (n = 6) provided a muscle biopsy of the pectoralis major muscle during mastectomy, lumpectomy, or breast reconstruction surgeries. The breast cancer patients were diagnosed with either luminal (ER+ /PR+ , n = 6), triple positive (ER+ /PR+ /Her2/neu+ , n = 5), or triple negative (ER/PR/Her2/neu, n = 3) breast tumours and were being treated with curative intent either with neoadjuvant chemotherapy followed by surgery or surgery followed by standard post-operative therapy. Biopsies were used for RNA-sequencing to compare the skeletal muscle gene expression patterns between breast cancer patients and non-cancer patients. The C57BL/6 mouse syngeneic mammary tumour cell line, E0771, was used to induce mammary tumours in immunocompetent mice, and isometric muscle contractile properties and fatigue properties were analysed following 4 weeks of tumour growth. Results RNA-sequencing and subsequent bioinformatics analyses revealed a dysregulation of canonical pathways involved in oxidative phosphorylation, mitochondrial dysfunction, peroxisome proliferator-activated receptor signalling and activation, and IL-15 signalling and production. In a preclinical mouse model of breast cancer, the rate of muscle fatigue was greater in mice exposed to mammary tumour growth for 4 weeks, and this greater muscle fatigue was attenuated in transgenic mice that overexpressed the cytokine IL-15. Conclusions Our data identify novel genes and pathways dysregulated in the muscles of breast cancer patients with early stage non-metastatic disease, with particularly aberrant expression among genes that would predispose these patients to greater muscle fatigue. Furthermore, we demonstrate that IL-15 overexpression can attenuate muscle fatigue associated with mammary tumour growth in a preclinical mouse model of breast cancer. Therefore, we propose that skeletal muscle fatigue is an inherent consequence of breast tumour growth, and this greater fatigue can be targeted therapeutically

Factors affecting poor breast feathering in modern turkeys

Sternal Bursitis (breast blisters) and Focal Ulcerative Dermatitis (breast buttons) cause depressed welfare and are an important source of economic loss in market turkeys. Such lesions are common in modem turkeys and feathers may offer some protection to the breast from environmental challenges. Feather growth is poor in modem compared with traditional turkeys and feathers may be absent over the breast region. This study quantified and compared feather growth in a modem commercial turkey with that in an unrelated traditional turkey and investigated the lack of breast feathers in the large modem bird.A comparative study found that feather growth had not increased with selection for body weight in the modem turkey and that the growth of breast feathers from the cranial region o f the breast tract appeared to be impaired. Modern birds spent more time resting than traditional turkeys.Three possible causes of poor breast feathering were examined. First, the reduction in feather growth was an adaptive response to increased heat production resulting from fast growth rates. Second, there was competition between muscle and feathers for essential nutrients such as amino acids. Third, selection for increased breast muscle mass has not resulted in an increase in feather number and was associated with stretching of the skin and poor breast feathering.Modem turkeys reared at high (26°C) and low (15°C) ambient temperatures showed no differences in feather growth. These turkeys were also fed ad libitum or restricted quantities of feed. Turkeys on restricted feeding showed a general decrease in feather growth apart from the cranial breast feathers that were increased in length.Nutrition experiments suggested that, in the modem turkey, protein was preferentially partitioned to feather growth and that the amino acids arginine and methionine were used for feather growth in preference to muscle growth. When crude protein concentrations in the diet o f the modem turkey were deficient, feather growth was maintained at the expense of body and particularly breast muscle growth. The impaired development of cranial breast feathers was associated with rapid growth o f the breast muscle in the modern turkey and was not related to a deficiency of specific amino acids.No increase in feather follicle number and a reduction of the collagen content of breast skin in the modem turkey support the hypothesis that development of the integument has not increased in proportion to body weightIt was concluded that the impaired growth of cranial breast feathers was caused by the rapid growth and sedentary behaviour of the modem turkey resulting in prolonged pressure on the feather tracts of the breast

Effect of an immune challenge and two feed supplements on broiler chicken individual breast muscle protein synthesis rate

Optimization of broiler chicken breast muscle protein accretion is key for the efficient production of poultry meat, whose demand is steadily increasing. In a context where antimicrobial growth promoters use is being restricted, it is important to find alternatives as well as to characterize the effect of immunological stress on broiler chicken's growth. Despite its importance, research on broiler chicken muscle protein dynamics has mostly been limited to the study of mixed protein turnover. The present study aims to characterize the effect of a bacterial challenge and the feed supplementation of citrus and cucumber extracts on broiler chicken individual breast muscle proteins fractional synthesis rates (FSR) using a recently developed dynamic proteomics pipeline. Twenty-one day-old broiler chickens were administered a single 2H2O dose before being culled at different timepoints. A total of 60 breast muscle protein extracts from five experimental groups (Unchallenged, Challenged, Control Diet, Diet 1 and Diet 2) were analysed using a DDA proteomics approach. Proteomics data was filtered in order to reliably calculate multiple proteins FSR making use of a newly developed bioinformatics pipeline. Broiler breast muscle proteins FSR uniformly decreased following a bacterial challenge, this change was judged significant for 15 individual proteins, the two major functional clusters identified as well as for mixed breast muscle protein. Citrus or cucumber extract feed supplementation did not show any effect on the breast muscle protein FSR of immunologically challenged broilers. The present study has identified potential predictive markers of breast muscle growth and provided new information on broiler chicken breast muscle protein synthesis which could be essential for improving the efficiency of broiler chicken meat production. SIGNIFICANCE: The present study constitutes the first dynamic proteomics study conducted in a farm animal species which has characterized FSR in a large number of proteins, establishing a precedent for biomarker discovery and assessment of health and growth status. Moreover, it has been evidenced that the decrease in broiler chicken breast muscle protein following an immune challenge is a coordinated event which seems to be the main cause of the decreased growth observed in these animals.</p

Improving body composition in broiler chicks through the early life diet

The poultry industry relies heavily on the efficient growth performance of broilers to provide quality breast meat at a low cost to meet consumer demand. However, high efficiency of broilers is also related to the occurrence and severity of skeletal muscle abnormalities like wooden breast. This study investigated the efficacy of incorporating long-chain omega-3 polyunsaturated fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), into the diets of hens and their offspring on altering the causative features of wooden breast. Early exposure to these fatty acids in broilers has shown to reduce adiposity, and may address excess adipogenesis seen in wooden breast. Physical characteristics of weight gain and relative breast weight were measured to confirm that fish oil did not compromise growth. Histological analysis of the breast showed that the perinatal fish oil diet promoted growth of larger muscle fibers and the maternal fish oil programmed reduced adipocyte size. Gene expression analysis results proposed the mechanisms that prompted differences in muscle fiber size area between diets namely, the increase in early myogenic marker expression, PAX7 and MYOD1. The increased expression of FABP4 seen in the perinatal fish oil diet groups may be attributed to a relatively new understanding of its function in muscle, and potentially an increase in fatty acid oxidation. Altering the hypertrophic growth rate of high efficiency broilers may assist in preventing growth that exceeds nutrient and oxygen provision seen in wooden breast. Primary satellite cells were collected from a subset of chicks that only differed by the maternal fish or soybean oil diets. Satellite cells isolated from the maternal fish oil group accumulated significantly less triglyceride versus maternal soybean oil. Decreasing elevated adipogenesis seen in the development of wooden breast may help to lessen the severity of the myopathy. In conclusion, future research is needed to identify the long term impacts fish oil supplementation can have on muscle development and adiposity in broilers at market age

Muscle Abnormalities and Meat Quality Consequences in Modern Turkey Hybrids

Turkey meat is the second most consumed poultry meat worldwide and represents an economic source of high-quality protein for human consumption. To fulfill the increasing demand for turkey meat, breeding companies have been selecting genetic lines with increased growth potential and breast muscle proportion. Moreover, the progressive shift toward further processed products has emphasized the need for higher standards in poultry meat to improve its technological characteristics and functional properties (i.e., water-holding capacity). However, as observed for broiler chickens, a growing body of scientific evidence suggests that the intense selection for the aforementioned traits could be associated with a greater occurrence of growth-related myopathies and abnormalities and, consequently, to increased downgrading rates and overall reduction of meat quality characteristics. In the past, muscle abnormalities such as deep pectoral myopathy, pale-soft-and-exudative-like meat, and focal myopathy have been reported in turkey lines selected for increased growth rate. In addition, the presence of white striations in the superficial layer of pectoralis major muscle, as well as the tendency of muscle fiber bundles to separate resulting in an altered breast muscle structure, has been detected in commercial turkey abattoirs. Furthermore, past investigations revealed the presence of another quality issue depicted by an overall toughening of the breast muscle. These meat abnormalities seem to macroscopically overlap the white striping, spaghetti meat, and wooden breast conditions observed in pectoral muscle of fast-growing, high-breast-yield chicken hybrids, respectively. Considering the high economic impact of these growth-related abnormalities in broilers, there is an increasing interest of the turkey industry in estimating the occurrence and the impact of these meat quality issues also in the modern turkey lines. Studies have been recently conducted to assess the effect of the genotype on the occurrence of these emerging growth-related defects and to evaluate how meat quality properties are affected by white-striping condition in turkeys, respectively. Therefore, this review aims to provide a critical overview of the current understanding regarding the growth-related abnormalities and their impact on meat quality in modern turkey hybrids with the hope that this information may improve the knowledge concerning their overall effect on poultry meat

The Impact of Thyme and Oregano Essential Oils Dietary Supplementation on Broiler Health, Growth Performance, and Prevalence of Growth-Related Breast Muscle Abnormalities

The objective of this study was to investigate the effects of thyme and oregano essential oils (as growth promotors), individually and in combination, on the health, growth performance, and prevalence of muscle abnormalities in broiler chickens. Six hundred day-old Cobb 500 hybrid chickens were randomized into four dietary treatment groups with three replicates each. Chicks in the control group (C) received a basal diet, while the experimental treatment groups received basal diets containing 350 mg/kg of thyme oil (T1), 350 mg/kg of oregano oil (T2), and 350 mg/kg of thyme and oregano oil (T3). Growth performance parameters were evaluated at 14, 28, and 42 days. The broilers in treatments T1 and T2 had significantly higher body weights than the control group. The feed conversion ratio was the lowest in chicks who received oregano oil, followed by those fed thyme oil. The overall prevalence of growth-related breast muscle abnormalities (including white striping and white striping combined with wooden breast) in groups receiving essential oils (T1, T2, and T3) was significantly higher than in the control group (C). The thyme and oregano oil diets showed no significant differences in antibody titers against Newcastle disease or interferon-γ (INF-γ) serum levels. In conclusion, thyme and oregano oils had a positive impact on the growth performance of broiler chickens but increased the incidence of growth-related breast muscle abnormalities

BODY WEIGHT, MUSCLE WIGHT, PROTEIN, DNA AND RNA CONTENTS IN BREAST MUSCLE (M. Pectoralis Major) OF SELECTED LOCAL MEAT CHICKEN FED ON A DIFFERENT LEVEL OF KIAPU (Pistia stratiotes L.) IN FERMENTED DIET

The study to evaluate changes in body weight, muscle weight, muscle protein content and total DNA and RNA on breast muscle of selectedlocal chicken due to different levels of fermented feed containing Kiapu (Pistia stratiotes L.) was conducted using a factorial randomized designfor 7 weeks. This study used 72 selected local chickens, which were separated into 2 groups (male and female) and fed on 3 types of feedtreatment, namely P0 (control treatment with 100% commercial feed), P1 (80% commercial feed + 20% fermented Kiapu feed), and P2 (70%commercial feed + 30% fermented Kiapu feed). Parameters were body weight, muscle weight, muscle protein content and total DNA and RNAon breast muscle of chicken. Total protein, DNA and RNA content were analysed by enzymatic reactions of prokaryotic cell and measured with aUV-Spectrophotometer according to the specified OD (optical density). The results showed that feeding Kiapu fermented 20-30% increased bodyweight and protein content of breast muscle of female chicken by change in DNA content. However, the feeding treatment had no changes inmuscle weight and RNA content of both in male and female chicken. On the other hand, substitution of 20-30% Kiapu fermented feed causednegative changes in DNA level of breast muscle. From this study, it was concluded that substitution of fermented feed containing 20-30% Kiapuassociated with the growth process of breast muscle protein is suitable for female but not suitable for male chicken

Predicted optimum ambient temperatures for broiler chickens to dissipate metabolic heat do not affect performance or improve breast muscle quality

<p></p><p>An experiment was conducted to test the hypothesis that muscle damage in fast-growing broiler chickens is associated with an ambient temperature that does not permit the birds to lose metabolic heat resulting in physiological heat stress and a reduction in meat quality.</p><p>The experiment was performed in 4 climate chambers and was repeated in 2 trials using a total of 200 male broiler chickens. Two treatments compared the recommended temperature profile and a cool regimen. The cool regimen was defined by a theoretical model that determined the environmental temperature that would enable heat generated by the bird to be lost to the environment.</p><p>There were no differences in growth rate or feed intake between the two treatments. Breast muscles from birds on the recommended temperature regimen were lighter, less red and more yellow than those from the cool temperature regimen. There were no differences in moisture loss or shear strength but stiffness was greater in breast muscle from birds housed in the cool compared to the recommended regimen.</p><p>Histopathological changes in the breast muscle were similar in both treatments and were characterised by mild to severe myofibre degeneration and necrosis with regeneration, fibrosis and adipocyte infiltration. There was no difference in plasma creatine kinase activity, a measure of muscle cell damage, between the two treatments consistent with the absence of differences in muscle pathology.</p><p>It was concluded that breast muscle damage in fast-growing broiler chickens was not the result of an inability to lose metabolic heat at recommended ambient temperatures. The results suggest that muscle cell damage and breast meat quality concerns in modern broiler chickens are related to genetic selection for muscle yields and that genetic selection to address breast muscle integrity in a balanced breeding programme is imperative.</p><p></p> <p>An experiment was conducted to test the hypothesis that muscle damage in fast-growing broiler chickens is associated with an ambient temperature that does not permit the birds to lose metabolic heat resulting in physiological heat stress and a reduction in meat quality.</p> <p>The experiment was performed in 4 climate chambers and was repeated in 2 trials using a total of 200 male broiler chickens. Two treatments compared the recommended temperature profile and a cool regimen. The cool regimen was defined by a theoretical model that determined the environmental temperature that would enable heat generated by the bird to be lost to the environment.</p> <p>There were no differences in growth rate or feed intake between the two treatments. Breast muscles from birds on the recommended temperature regimen were lighter, less red and more yellow than those from the cool temperature regimen. There were no differences in moisture loss or shear strength but stiffness was greater in breast muscle from birds housed in the cool compared to the recommended regimen.</p> <p>Histopathological changes in the breast muscle were similar in both treatments and were characterised by mild to severe myofibre degeneration and necrosis with regeneration, fibrosis and adipocyte infiltration. There was no difference in plasma creatine kinase activity, a measure of muscle cell damage, between the two treatments consistent with the absence of differences in muscle pathology.</p> <p>It was concluded that breast muscle damage in fast-growing broiler chickens was not the result of an inability to lose metabolic heat at recommended ambient temperatures. The results suggest that muscle cell damage and breast meat quality concerns in modern broiler chickens are related to genetic selection for muscle yields and that genetic selection to address breast muscle integrity in a balanced breeding programme is imperative.</p

In-ovo feeding with creatine monohydrate: implications for chicken energy reserves and breast muscle development during the pre-post hatching period

The most dynamic period throughout the lifespan of broiler chickens is the pre-post-hatching period, entailing profound effects on their energy status, survival rate, body weight, and muscle growth. Given the significance of this pivotal period, we evaluated the effect of in-ovo feeding (IOF) with creatine monohydrate on late-term embryos’ and hatchlings’ energy reserves and post-hatch breast muscle development. The results demonstrate that IOF with creatine elevates the levels of high-energy-value molecules (creatine and glycogen) in the liver, breast muscle and yolk sac tissues 48&nbsp;h post IOF, on embryonic day 19 (p &lt; 0.03). Despite this evidence, using a novel automated image analysis tool on day 14 post-hatch, we found a significantly higher number of myofibers with lower diameter and area in the IOF creatine group compared to the control and IOF NaCl groups (p &lt; 0.004). Gene expression analysis, at hatch, revealed that IOF creatine group had significantly higher expression levels of myogenin (MYOG) and insulin-like growth factor 1 (IGF1), related to differentiation of myogenic cells (p &lt; 0.01), and lower expression of myogenic differentiation protein 1 (MyoD), related to their proliferation (p &lt; 0.04). These results imply a possible effect of IOF with creatine on breast muscle development through differential expression of genes involved in myogenic proliferation and differentiation. The findings provide valuable insights into the potential of pre-hatch enrichment with creatine in modulating post-hatch muscle growth and development