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1.
J Sci Food Agric ; 100(2): 665-671, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31583700

RESUMO

BACKGROUND: Muscle fat content and fatty acid composition play an important role in poultry flavor and taste. To investigate the effects of pioglitazone hydrochloride (PGZ) on growth performance and thigh muscle quality in yellow-feathered chickens, 360 female chickens were randomly divided into three groups and treated with three doses of PGZ (0, 7.5, and 15 mg kg-1 ) for 28 days. Each group had six replicates of 20 chickens. RESULTS: The results showed that dietary supplementation with 15 mg kg-1 PGZ increased average daily feed intake (ADFI) and the average daily gain (ADG) from 0 to 14 days. Furthermore, the triglyceride (TG) level was decreased by 15 mg kg-1 PGZ, whereas the eviscerated yield was increased. The relative weight of the heart and kidneys showed a linear increase with dietary PGZ supplementation, and the drip loss of the thigh muscle was significantly decreased by 15 mg kg-1 PGZ supplementation. Moreover, a* value, intramuscular fat (IMF), and polyunsaturated fatty acids (PUFAs) showed a linear increase, and pH24 h and drip loss showed a quadratic influence with the levels of PGZ supplementation. In particular, the PUFA proportion was increased by 7.63% and 9.14% in the 7.5 mg kg-1 PGZ and 15 mg kg-1 PGZ groups, respectively. Additionally, 15 mg kg-1 of PGZ increased the total antioxidant capacity (T-AOC) and glutathione peroxidase (GSH-PX ) activity. CONCLUSION: In summary, 15 mg kg-1 PGZ has substantial effects on growth performance and meat quality, particularly by decreasing drip loss and increasing IMF content, PUFA proportions, and antioxidant ability. © 2019 Society of Chemical Industry.


Assuntos
Antioxidantes/metabolismo , Galinhas/metabolismo , Ácidos Graxos/química , Músculo Esquelético/metabolismo , Pioglitazona/administração & dosagem , Coxa da Perna/crescimento & desenvolvimento , Ração Animal/análise , Animais , Galinhas/crescimento & desenvolvimento , Suplementos Nutricionais/análise , Ácidos Graxos/metabolismo , Feminino , Glutationa Peroxidase/metabolismo , Carne/análise , Músculo Esquelético/química , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/crescimento & desenvolvimento
2.
J Sports Sci Med ; 18(4): 751-757, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31827360

RESUMO

This study aimed to examine longitudinal age-related changes in muscle morphology and jump and sprint performances of youth athletes. The subjects of this longitudinal study were 41 youth male basketball players who were assigned to late, mid, and early groups based on differences regarding the estimated age at peak height velocity. The vastus medialis, vastus intermedius, rectus femoris, vastus lateralis, biceps brachii, and triceps brachii thicknesses were assessed using ultrasonography. The subjects' anaerobic capacities were evaluated based on Abalakov jumps and 20-m sprint time. After 1 year, the vastus medialis and biceps brachii thicknesses increased significantly in all groups, and the rectus femoris, vastus intermedius, and vastus lateralis thicknesses increased significantly in the late and mid groups, but not in the early group. The Abalakov jumps and 20-m sprint time improved significantly in all groups. The early group's 10-m sprint time improved significantly. Cross-sectional comparisons showed that after 1 year, the early group's Abalakov jumps and 20-m sprint time at baseline, its Abalakov jumps, and 10-m and 20-m sprint times were significantly better than those in the mid and late groups. Hence, significant muscle growth occurred before the athletes reached the age at peak height velocity. During puberty, late maturers' sprint times and jump performances may not catch up with those of early maturers. The speed and tempo of the morphological growth and anaerobic ability of athletes in the same age category depend on athletes' biological maturity.


Assuntos
Desempenho Atlético/fisiologia , Basquetebol/fisiologia , Músculo Esquelético/anatomia & histologia , Músculo Esquelético/crescimento & desenvolvimento , Puberdade/fisiologia , Adolescente , Fatores Etários , Estatura/fisiologia , Criança , Teste de Esforço , Humanos , Estudos Longitudinais , Masculino , Músculo Esquelético/diagnóstico por imagem , Ultrassonografia
3.
PLoS Genet ; 15(10): e1008279, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31603892

RESUMO

Muscle development and lipid accumulation in muscle critically affect meat quality of livestock. However, the genetic factors underlying myofiber-type specification and intramuscular fat (IMF) accumulation remain to be elucidated. Using two independent intercrosses between Western commercial breeds and Korean native pigs (KNPs) and a joint linkage-linkage disequilibrium analysis, we identified a 488.1-kb region on porcine chromosome 12 that affects both reddish meat color (a*) and IMF. In this critical region, only the MYH3 gene, encoding myosin heavy chain 3, was found to be preferentially overexpressed in the skeletal muscle of KNPs. Subsequently, MYH3-transgenic mice demonstrated that this gene controls both myofiber-type specification and adipogenesis in skeletal muscle. We discovered a structural variant in the promotor/regulatory region of MYH3 for which Q allele carriers exhibited significantly higher values of a* and IMF than q allele carriers. Furthermore, chromatin immunoprecipitation and cotransfection assays showed that the structural variant in the 5'-flanking region of MYH3 abrogated the binding of the myogenic regulatory factors (MYF5, MYOD, MYOG, and MRF4). The allele distribution of MYH3 among pig populations worldwide indicated that the MYH3 Q allele is of Asian origin and likely predates domestication. In conclusion, we identified a functional regulatory sequence variant in porcine MYH3 that provides novel insights into the genetic basis of the regulation of myofiber type ratios and associated changes in IMF in pigs. The MYH3 variant can play an important role in improving pork quality in current breeding programs.


Assuntos
Adipogenia/genética , Proteínas do Citoesqueleto/genética , Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/crescimento & desenvolvimento , Miosinas/genética , Tecido Adiposo/crescimento & desenvolvimento , Tecido Adiposo/metabolismo , Animais , Cruzamento , Regulação da Expressão Gênica , Estudo de Associação Genômica Ampla , Genótipo , Carne , Camundongos , Camundongos Transgênicos , Músculo Esquelético/metabolismo , Cadeias Pesadas de Miosina/genética , Motivos de Nucleotídeos , Sus scrofa/genética , Sus scrofa/metabolismo , Suínos
4.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 33(9): 1088-1094, 2019 Sep 15.
Artigo em Chinês | MEDLINE | ID: mdl-31512448

RESUMO

Objective: To investigate the effect of isokinetic training of thigh muscle group on graft remodeling after anterior cruciate ligament (ACL) reconstruction, and summarize the relevant rules to guide the clinic. Methods: Between August 2016 and December 2016, forty patients underwent arthroscopic ACL reconstruction using hamstring tendon were randomly divided into isokinetic group and control group ( n=20). The two groups of patients underwent staged rehabilitation treatment. The isokinetic group replaced the traditional intervention with the corresponding isokinetic strength training from 3 to 6 months after operation, and the traditional rehabilitation intervention was used in the control group. Finally, 12 cases of isokinetic group and 12 cases of control group with complete follow-up were enrolled in study. There was no significant difference in gender, age, body mass index, side of injury, the interval between injury and operation, and preoperative International Knee Documentation Committee (IKDC) score between the two groups ( P>0.05). The peak torque (PT) of knee extension and flexion and hamstring quadriceps ratio (H/Q) were measured at 3 months, 6 months, 12 months, and the second-look arthroscopy. The MRI examination was performed at the same time to evaluate graft remodeling. The shape, tension, and degree of vascularization of grafts were observed under arthroscopy. The grafts were harvested and observed by HE staining. Results: The invertal between ACL reconstruction and the second-look arthroscopy was (23.57±3.23) months in isokinetic group and (23.22±3.56) months in control group, showing no significant difference between the two groups ( P>0.05). At the second-look arthroscopy, the IKDC score was 90.45±4.73 in isokinetic group and 89.32±4.54 in control group, showing significant differences when compared with preoperative scores in the two groups ( P<0.05). But there was no significant difference between the two groups ( t=0.868, P=0.404). At 3 months after operation, there was no significant difference in the PT of knee extension and flexion between the two groups ( P>0.05). At 6 months, 12 months, and the second-look arthroscopy, the PT of knee extension and flexion in isokinetic group were higher than those in control group ( P<0.05). The H/Q at 6 months and 12 months were higher in isokinetic group than in control group, and the differences were significant ( P<0.05). There was no significant difference in MRI score between the two groups at 3 months, 6 months, and the second-look arthroscopy ( P>0.05). The MRI score at 12 months was significantly higher in isokinetic group than in control group ( P<0.05). At the second-look arthroscopy, there was no significant difference in the arthroscopic score between the two groups ( P>0.05), and the histological score of the isokinetic group was superior to the control group ( P<0.05). Conclusion: On the basis of regular rehabilitation training, using the isokinetic training system to develop a suitable post-surgical isokinetic rehabilitation training program is helpful in early muscle strength recovery, early graft remodeling, and even long-term histological results after ACL reconstruction.


Assuntos
Lesões do Ligamento Cruzado Anterior , Reconstrução do Ligamento Cruzado Anterior , Exercício , Músculo Esquelético , Ligamento Cruzado Anterior/cirurgia , Lesões do Ligamento Cruzado Anterior/cirurgia , Reconstrução do Ligamento Cruzado Anterior/reabilitação , Artroscopia , Feminino , Humanos , Masculino , Músculo Esquelético/crescimento & desenvolvimento , Coxa da Perna/crescimento & desenvolvimento , Resultado do Tratamento
5.
Int J Mol Sci ; 20(18)2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31540432

RESUMO

Myostatin (MSTN) negatively regulates muscle growth and development through inhibiting myoblast proliferation and differentiation. Five alternative splicing isoforms of MSTN (MSTN-A to MSTN-E) have been discovered in domestic avian species. MSTN-A has high expression in skeletal muscle and encodes the full-length peptide with anti-myogenic activity. Another isoform, MSTN-B, is also highly expressed in skeletal muscle and encodes a truncated peptide that has pro-myogenic capabilities in vitro, which include promoting the proliferation and differentiation of quail muscle precursor cells. The objective of this study was to investigate overexpression of MSTN-B in vivo by using two independent lines of transgenic Japanese quail with expression directed in the skeletal muscle. Unexpectedly, the chicken skeletal muscle alpha actin 1 (cACTA1) promoter resulted in restricted exogenous MSTN-B protein expression to certain skeletal muscles, such as the gastrocnemius and tibialis anterior, but not the pectoralis major muscle. Gastrocnemius weight as a percentage of body weight in transgenic quail was increased compared to non-transgenic quail at posthatch day 21 (D21) and posthatch D42. An increase in the size of the gastrocnemius in transgenic quail was attributed to an increase in fiber number but not fiber cross-sectional area (CSA). During embryonic development, paired box 7 (PAX7) expression was prolonged in the transgenic embryos, but other myogenic regulatory factors (MRFs) were unchanged after MSTN-B overexpression. Taken together, these data provide novel insights into the regulation of skeletal muscle development by alternative splicing mechanisms in avians.


Assuntos
Processamento Alternativo , Proteínas Aviárias/genética , Músculo Esquelético/crescimento & desenvolvimento , Miostatina/genética , Codorniz/crescimento & desenvolvimento , Animais , Feminino , Hiperplasia/genética , Hiperplasia/patologia , Hiperplasia/veterinária , Masculino , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Isoformas de Proteínas/genética , Codorniz/genética
6.
Eur J Appl Physiol ; 119(10): 2349-2362, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31473806

RESUMO

PURPOSE: The aim of the current meta-analysis was to examine the extent to which there are differences in upper extremity motor synergies across different age groups in manipulative tasks. METHODS: The studies that used the uncontrolled manifold method to examine the effect of age on motor synergies in multi-joint and multi-finger tasks were selected. Sixteen relevant studies from 1154 articles were selected for the meta-analysis-4 and 12 studies considered multi-joint kinematics and multi-finger kinetic tasks respectively. RESULTS: The results of the meta-analysis suggested reduced strength of synergies in multi-finger task in older adults, but this was not the case for synergies in multi-joint task. Part of this age-related difference in finger function is related to the increased variability in total force in grasping tasks. However, reductions in the strength of multi-finger synergies in hand functions following ageing appear to depend on the characteristics of the task. CONCLUSIONS: These findings indicate that the cooperation among fingers to stabilise the total required force to apply for grasping and other fine motor skills is less efficient in older adults that might affect the quality of manipulative tasks.


Assuntos
Envelhecimento/fisiologia , Destreza Motora , Músculo Esquelético/fisiologia , Fenômenos Biomecânicos , Dedos/crescimento & desenvolvimento , Dedos/fisiologia , Força da Mão , Humanos , Contração Muscular , Músculo Esquelético/crescimento & desenvolvimento
7.
J Int Soc Sports Nutr ; 16(1): 39, 2019 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-31500646

RESUMO

BACKGROUND: Enzymatically modified isoquercitrin (EMIQ), a water-soluble quercetin, has been shown to intensify muscle hypertrophy in mice. We investigated the effect of EMIQ in supplementary protein powder on athlete body composition. METHODS: Forty Japanese males who played American football (age: 19.8 ± 1.4 years; body height: 174.1 ± 6.0 cm; body mass: 75.5 ± 10.7 kg) were assigned to a randomized, placebo-controlled, double-blind trial of parallel group. Participants received either EMIQ in whey protein (EW, n = 19) or contrast whey protein (W, n = 20) 6 days per week over 4 months. Body composition was assessed using dual-energy X-ray absorptiometry. Markers of oxidative stress, derivatives of reactive oxygen metabolites (d-ROMs) and biological antioxidant potential (BAP), were assessed using a free radical analytical system. Data were analyzed using a univariate and repeated measures general model statistics. RESULTS: After 4 months, changes in lower limb fat-free mass and muscle mass were significantly greater in the EW group than in the W group (mean change ±95% CI; W: 324.1 ± 284.3, EW: 950.3 ± 473.2, p = 0.031, W: 255.7 ± 288.6, EW: 930.9 ± 471.5, p = 0.021, respectively). Moreover, the EW group exhibited a significantly higher BAP/d-ROMs ratio, antioxidation index, than the W group after 4 months (mean change ± SD; W: 8.8 ± 1.1, EW: 10.3 ± 2.8; p = 0.028). No significant differences in body mass, lean body mass, fat mass, or lower limb fat mass were observed between the groups. CONCLUSION: Ingestion of EMIQ in supplementary protein powder for 4 months exerts antioxidant effects and increases muscle mass among American football players. TRIAL REGISTRATION: University Hospital Medical Information Network Clinical Trial Registry, UMIN000036036 . Retrospectively registered in 2019.


Assuntos
Composição Corporal , Suplementos Nutricionais , Músculo Esquelético/crescimento & desenvolvimento , Quercetina/análogos & derivados , Absorciometria de Fóton , Adolescente , Atletas , Proteínas na Dieta/administração & dosagem , Método Duplo-Cego , Futebol Americano , Humanos , Masculino , Quercetina/administração & dosagem , Fenômenos Fisiológicos da Nutrição Esportiva , Adulto Jovem
8.
Genes (Basel) ; 10(8)2019 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-31434291

RESUMO

The chicken is a common type of poultry that is economically important both for its medicinal and nutritional values. Previous studies have found that free-range chickens have more skeletal muscle mass. The methyltransferase-like 21C gene (METTL21C) plays an important role in muscle development; however, there have been few reports on the role of METTL21C in chickens. In this study, we performed a genome-wide identification of chicken METTL21C genes and analyzed their phylogeny, transcriptional expression profile, and real-time quantitative polymerase chain reaction (qPCR). We identified 10 GgMETTL21C genes from chickens, 11 from mice, and 32 from humans, and these genes were divided into six groups, which showed a large amount of variation among these three species. A total of 15 motifs were detected in METTL21C genes, and the intron phase of the gene structure showed that the METTL21C gene family was conservative in evolution. Further, both the transcript data and qPCR showed that a single gene's (GgMETTL21C3) expression level increased with the muscle development of chickens, indicating that the METTL21C genes are involved in the development of chicken muscles. Our results provide some reference value for the subsequent study of the function of METTL21C.


Assuntos
Proteínas Aviárias/genética , Galinhas/genética , Metiltransferases/genética , Animais , Proteínas Aviárias/metabolismo , Galinhas/metabolismo , Sequência Conservada , Metiltransferases/metabolismo , Família Multigênica , Músculo Esquelético/crescimento & desenvolvimento , Músculo Esquelético/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
9.
Eur J Appl Physiol ; 119(10): 2301-2312, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31451954

RESUMO

PURPOSE: To compare concentric and eccentric cycling performed by older adults for metabolic demand and post-exercise oxidative stress, inflammation and muscle damage. METHODS: Eight male and two female healthy older adults (60.4 ± 6.8 years) performed 30 min of moderate-intensity concentric (CONC-M: 50% maximum power output; POmax) and eccentric cycling (ECC-M: 50% POmax) and high-intensity eccentric cycling (ECC-H: 100% POmax) in a randomized order. Average power output (PO), oxygen consumption (VO2), heart rate (HR) and rate of perceived exertion were recorded during cycling. Some indirect markers of muscle damage were assessed before, and immediately, 24 and 48 h after cycling. Markers of oxidative stress (malondialdehyde: MDA, protein carbonyl), antioxidant (total antioxidant capacity, glutathione peroxidase activity: GPx) and inflammation (IL-6, TNF-α) were measured before and 5 min after cycling. RESULTS: PO in ECC-H (202.6 ± 78.5 W) was > 50% greater (P < 0.05) than that of CONC-M (98.6 ± 33.1 W) and ECC-M (112.0 ± 42.1 W). VO2 and HR were also greater (P < 0.05) for ECC-H than CONC-M (50% and 17%, respectively) and ECC-M (40% and 23%, respectively). Muscle strength loss at 1 day post-exercise (8-22%), peak soreness (10-62 mm) and creatine kinase activity (30-250 IU/L) after ECC-H were greater (P < 0.05) than those after ECC-M and CONC-M. MDA decreased (P < 0.05) after CONC-M (- 28%) and ECC-M (- 22%), but not after ECC-H. GPx activity increased after all exercises similarly (20-27%). IL-6 increased (P < 0.05) only after ECC-H (18%). CONCLUSION: Oxidative stress was minimal after eccentric cycling, but high-intensity eccentric cycling induced moderate muscle damage and inflammation, which is not desirable for older individuals.


Assuntos
Mialgia/etiologia , Estresse Oxidativo , Condicionamento Físico Humano/métodos , Idoso , Feminino , Glutationa Peroxidase/sangue , Frequência Cardíaca , Humanos , Interleucina-6/sangue , Masculino , Malondialdeído/sangue , Pessoa de Meia-Idade , Contração Muscular , Músculo Esquelético/crescimento & desenvolvimento , Músculo Esquelético/metabolismo , Músculo Esquelético/fisiologia , Mialgia/sangue , Consumo de Oxigênio , Condicionamento Físico Humano/efeitos adversos , Esforço Físico , Carbonilação Proteica , Distribuição Aleatória , Fator de Necrose Tumoral alfa/sangue
10.
J Fish Biol ; 95(3): 940-951, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31294823

RESUMO

Myotomal slow-oxidative muscle (SM) powers continuous swimming and generates heat needed to maintain elevated locomotor muscle temperatures (regional endothermy) in tunas. This study describes how the amount and distribution of myotomal SM increases with fish size and age in juvenile yellowfin tuna Thunnus albacares in relationship to the development of regional endothermy. In T. albacares juveniles 40-74 mm fork length (LF ; n = 23) raised from fertilised eggs at the Inter-American Tropical Tuna Commission Achotines Laboratory in Panama and larger juveniles (118-344 mm LF ; n = 5) collected by hook and line off of Oahu, Hawaii, USA, SM was identified by histochemical staining for the mitochondrial enzyme succinic dehydrogenase or by colour (in the two largest individuals). The cross-sectional area of myotomal SM at 60% LF , a position with maximal percentage of SM in larger T. albacares, increased exponentially with LF . The percentage of total cross-sectional area composed of SM at 60% LF increased significantly with both LF and age, suggesting that SM growth occurs throughout the size range of T. albacares juveniles studied. In addition, the percentage of SM at 60% LF that is medial increased asymptotically with LF . The increases in amount of SM and medial SM, along with the development of the counter-current heat-exchanger blood vessels that retain heat, allow larger tuna juveniles to maintain elevated and relatively stable SM temperatures, facilitating range expansion into cooler waters.


Assuntos
Envelhecimento , Tamanho Corporal , Fibras Musculares de Contração Lenta/fisiologia , Músculo Esquelético/crescimento & desenvolvimento , Atum/crescimento & desenvolvimento , Animais , Hawaii , Consumo de Oxigênio , Panamá , Natação , Temperatura Ambiente
11.
Food Chem ; 300: 125173, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31319335

RESUMO

The administration of anabolic agents in farm animals to improve meat production has been prohibited in EU, due to the potential risks to human health. Meat quality was investigated to detect the effects of illegal administration of dexamethasone or prednisolone or 17ß-estradiol on Charolais bulls. Three groups of 6 bulls were treated and 12 bulls were the control. Meat quality parameters were measured on live animals, carcasses and on samples of Longissimus thoracis and multivariate statistical data analysis was applied. In Charolais bulls, these parameters were affected by growth promoter administration and the multivariate canonical discriminant analysis was able to distinguish between treated and untreated animals mainly due to three electronic nose's parameters, 24 h carcass temperature and drip loss. Therefore, meat quality control and the multivariate analysis could be useful as a first screening to address targeted controls on farms suspected of illicit use of growth promoters.


Assuntos
Análise de Alimentos/métodos , Substâncias de Crescimento/farmacologia , Carne , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/crescimento & desenvolvimento , Animais , Bovinos , Dexametasona/farmacologia , Análise Discriminante , Nariz Eletrônico , Estradiol/farmacologia , Fazendas , Análise de Alimentos/instrumentação , Análise de Alimentos/estatística & dados numéricos , Qualidade dos Alimentos , Masculino , Carne/análise , Prednisolona/farmacologia
12.
J Strength Cond Res ; 33 Suppl 1: S140-S151, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31260419

RESUMO

Zaroni, RS, Brigatto, FA, Schoenfeld, BJ, Braz, TV, Benvenutti, JC, Germano, MD, Marchetti, PH, Aoki, MS, and Lopes, CR. High resistance-training frequency enhances muscle thickness in resistance-trained men. J Strength Cond Res 33(7S): S140-S151, 2019-The purpose of this study was to compare the effect a split training routine with muscle groups trained once per week (SPLIT) vs. whole-body split training routine with muscle groups trained 5 days per week (TOTAL) on neuromuscular adaptations in well-trained men. Eighteen healthy men (height = 177.8 ± 6.6 cm; total body mass = 84.4 ± 8.1 kg; age = 26.4 ± 4.6 years) were recruited to participate in this study. The experimental groups were matched according to baseline strength and then randomly assigned to 1 of the 2 experimental groups: SPLIT (n = 9) or TOTAL (n = 9). Prestudy and poststudy testing included 1RM for bench press, parallel back-squat and machine close-grip seated row, as well as an ultrasound analysis of the muscle thickness (MT) of the elbow flexors, triceps brachii, and vastus lateralis. After 8 weeks of training, no significant difference between groups was noted for all 1RM tests (p > 0.05). TOTAL induced a significantly greater increase in MT of the forearm flexors and vastus lateralis (p < 0.05). In conclusion, muscle strength increment is similar regardless of the experimental conditions studied; however, TOTAL may confer a potentially superior hypertrophic effect.


Assuntos
Músculo Esquelético/crescimento & desenvolvimento , Treinamento de Resistência/métodos , Fatores de Tempo , Adaptação Fisiológica , Adulto , Braço , Antebraço , Humanos , Masculino , Força Muscular , Músculo Esquelético/diagnóstico por imagem , Ultrassonografia , Adulto Jovem
13.
Dis Markers ; 2019: 9140789, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31354893

RESUMO

Obesity and inflammation are reportedly associated with the pathogenesis of sarcopenia, which is characterized by age-related loss of skeletal muscle mass. Intramuscular fat deposits have been found to compromise muscle integrity; however, the relevant fat compounds and their roles as mediators of muscular inflammation are not known. The aim of this study was to identify potential correlations between inflammation markers and lipid compounds that accumulate in the quadriceps muscle of previously described Sprague-Dawley (SD) rat model for high-fat diet- (HFD-) induced muscle loss. Six-month-old SD rats were continuously fed a control (CD) or HFD until the age of 21 months. Magnetic resonance imaging (MRI) revealed a significant decline in muscle cross-sectional area in male SD rats as a result of HFD, but not in female rats. Here, we developed a new procedure to quantitatively identify and classify the fatty acid methyl esters (FAMEs) in rats' quadriceps muscles from our former study using gas chromatography-mass spectrometry (GC-MS). Fatty acid analysis revealed accumulation of octadecadienoic (linoleic acid), octadecanoic (stearic acid), and octadecenoic (vaccenic acid) acids exclusively in the quadriceps muscles of male rats. The designated fatty acids were mainly incorporated into triacylglycerols (TAGs) or free fatty acids (FFAs), and their proportions were significantly elevated by consumption of a HFD. Furthermore, the number of resident immune cells and the levels of the chemokines RANTES, MCP-1, and MIP-2 were significantly increased in quadriceps muscle tissue of HFD-fed male, but not female rats. Together, HFD-induced muscle loss in aged male SD rats is associated with greater deposits of long-chain fatty acid esters and increased levels of the inflammatory markers RANTES, MCP-1, and MIP-2 in skeletal muscle tissue. This trend is further reinforced by long-term consumption of a HFD, which may provoke synergistic crosstalk between long-chain fatty acids and inflammatory pathways in sarcopenic muscle.


Assuntos
Quimiocinas/metabolismo , Ácidos Graxos Insaturados/metabolismo , Músculo Esquelético/metabolismo , Sarcopenia/metabolismo , Animais , Masculino , Músculo Esquelético/crescimento & desenvolvimento , Ratos , Ratos Sprague-Dawley , Fatores Sexuais
14.
Cell Mol Life Sci ; 76(24): 5041-5054, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31214725

RESUMO

Skeletal myogenesis is a highly coordinated process that involves cell proliferation, differentiation and fusion controlled by a complex gene regulatory network. The microRNA gene cluster miR-17-92 has been shown to be related to this process; however, the exact role of each cluster member remains unclear. Here, we show that miR-17 and miR-20a could effectively promote the differentiation of both C2C12 myoblasts and primary bovine satellite cells. In contrast, miR-18a might play a negative role in C2C12 cell differentiation, while miR-19 and miR-92a had little influence. Transcriptome and target analyses revealed that miR-17 could act on Ccnd2, Jak1 and Rhoc genes that are critical for cell proliferation and/or fusion. Notably, the addition of miR-19 could reverse the lethal effect of miR-17 and could thus facilitate the maturation of myotubes. Furthermore, by co-injecting the lentiviral shRNAs of miR-17 and miR-19 into mouse tibialis anterior muscles, we demonstrated the wound healing abilities of the two miRNAs. Our findings indicate that in combination with miR-19, miR-17 is a potent inducer of skeletal muscle differentiation.


Assuntos
Diferenciação Celular/genética , MicroRNAs/genética , Músculo Esquelético/crescimento & desenvolvimento , Animais , Bovinos , Proliferação de Células/genética , Ciclina D2/genética , Redes Reguladoras de Genes/genética , Janus Quinase 1/genética , Camundongos , Desenvolvimento Muscular/genética , Músculo Esquelético/metabolismo , Mioblastos/metabolismo , Proteína de Ligação a GTP rhoC/genética
15.
DNA Res ; 26(3): 261-272, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31231762

RESUMO

Adenosine-to-inosine (A-to-I) RNA editing meditated by adenosine deaminases acting on RNA (ADARs) enzymes is a widespread post-transcriptional event in mammals. However, A-to-I editing in skeletal muscle remains poorly understood. By integrating strand-specific RNA-seq, whole genome bisulphite sequencing, and genome sequencing data, we comprehensively profiled the A-to-I editome in developing skeletal muscles across 27 prenatal and postnatal stages in pig, an important farm animal and biomedical model. We detected 198,892 A-to-I editing sites and found that they occurred more frequently at prenatal stages and showed low conservation among pig, human, and mouse. Both the editing level and frequency decreased during development and were positively correlated with ADAR enzymes expression. The hyper-edited genes were functionally related to the cell cycle and cell division. A co-editing module associated with myogenesis was identified. The developmentally differential editing sites were functionally enriched in genes associated with muscle development, their editing levels were highly correlated with expression of their host mRNAs, and they potentially influenced the gain/loss of miRNA binding sites. Finally, we developed a database to visualize the Sus scrofa RNA editome. Our study presents the first profile of the dynamic A-to-I editome in developing animal skeletal muscle and provides evidences that RNA editing is a vital regulator of myogenesis.


Assuntos
Adenosina Desaminase/metabolismo , Músculo Esquelético/crescimento & desenvolvimento , Edição de RNA , RNA Mensageiro/metabolismo , Sus scrofa/crescimento & desenvolvimento , Adenosina Desaminase/genética , Animais , Bases de Dados Genéticas , Regulação da Expressão Gênica no Desenvolvimento , Masculino , Músculo Esquelético/enzimologia , Músculo Esquelético/metabolismo , Análise de Sequência de RNA , Sus scrofa/genética , Sus scrofa/metabolismo , Sequenciamento Completo do Genoma
16.
Genome Res ; 29(8): 1262-1276, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31249065

RESUMO

Organisms use endogenous clocks to adapt to the rhythmicity of the environment and to synchronize social activities. Although the circadian cycle is implicated in aging, it is unknown whether natural variation in its function contributes to differences in lifespan between populations and whether the circadian clock of specific tissues is key for longevity. We have sequenced the genomes of Drosophila melanogaster strains with exceptional longevity that were obtained via multiple rounds of selection from a parental strain. Comparison of genomic, transcriptomic, and proteomic data revealed that changes in gene expression due to intergenic polymorphisms are associated with longevity and preservation of skeletal muscle function with aging in these strains. Analysis of transcription factors differentially modulated in long-lived versus parental strains indicates a possible role of circadian clock core components. Specifically, there is higher period and timeless and lower cycle expression in the muscle of strains with delayed aging compared to the parental strain. These changes in the levels of circadian clock transcription factors lead to changes in the muscle circadian transcriptome, which includes genes involved in metabolism, proteolysis, and xenobiotic detoxification. Moreover, a skeletal muscle-specific increase in timeless expression extends lifespan and recapitulates some of the transcriptional and circadian changes that differentiate the long-lived from the parental strains. Altogether, these findings indicate that the muscle circadian clock is important for longevity and that circadian gene variants contribute to the evolutionary divergence in longevity across populations.


Assuntos
Fatores de Transcrição ARNTL/genética , Relógios Circadianos/genética , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Genoma de Inseto , Longevidade/genética , Músculo Esquelético/metabolismo , Proteínas Circadianas Period/genética , Fatores de Transcrição ARNTL/metabolismo , Animais , Evolução Biológica , Ritmo Circadiano/genética , DNA Intergênico/genética , DNA Intergênico/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/crescimento & desenvolvimento , Drosophila melanogaster/metabolismo , Genética Populacional , Genômica , Músculo Esquelético/crescimento & desenvolvimento , Proteínas Circadianas Period/metabolismo , Polimorfismo Genético , Transcriptoma , Sequenciamento Completo do Genoma
17.
Theriogenology ; 135: 109-114, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31207471

RESUMO

There is no data currently available on the semen quality and fertility of myostatin-knockout (MSTN-/-) boars. We showed that sexually mature adult homozygous MSTN mutant boars have an obvious "double muscling" phenotype, along with a MSTN-/- boar head, back, abdomen, eyes, and oral cavity. Additionally, no abnormalities were found in the reproductive organs. The semen color, odor, and pH also had no abnormalities. The MSTN-/- boars showed good sexual desire. The concentration, motility, plasma membrane integrity, deformity, acrosome integrity, and mitochondrial activity of the semen presented no significant differences from those of the control semen (Duroc). The ejaculation volume of the MSTN-/- boars was significantly lower than that of the control (168.78 ±â€¯6.70 and 223.11 ±â€¯21.21 mL, respectively). The rate of cleavage and blastocyst between the MSTN-/- and control boar semen were compared by in vitro fertilization. The results showed that in the eggs fertilized by the MSTN-/- boar semen, the two-cell and blastocyst rates were similar to those of the control semen (69.1 ±â€¯0.7% vs 65.2 ±â€¯1.6% and 20.2 ±â€¯1.2% vs 22.8 ±â€¯1.4% for the two-cell and blastocyst rates, respectively). In this study, nine healthy offspring were successfully produced through artificial insemination using the MSTN-/- boar semen. Thus, an MSTN-/- boar can be used as the terminal male parent and is expected to be developed into new super lean meat varieties in the future.


Assuntos
Miostatina/genética , Espermatozoides/fisiologia , Animais , Deleção de Genes , Masculino , Músculo Esquelético/crescimento & desenvolvimento , Análise do Sêmen
18.
Cell Mol Life Sci ; 76(23): 4795-4809, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31201465

RESUMO

Fibrillin microfibrils are ubiquitous elements of extracellular matrix assemblies that play crucial roles in regulating the bioavailability of growth factors of the transforming growth factor beta superfamily. Recently, several "a disintegrin and metalloproteinase with thrombospondin motifs" (ADAMTS) proteins were shown to regulate fibrillin microfibril function. Among them, ADAMTS17 is the causative gene of Weill-Marchesani syndrome (WMS) and Weill-Marchesani-like syndrome, of which common symptoms are ectopia lentis and short stature. ADAMTS17 has also been linked to height variation in humans; however, the molecular mechanisms whereby ADAMTS17 regulates skeletal growth remain unknown. Here, we generated Adamts17-/- mice to examine the role of Adamts17 in skeletogenesis. Adamts17-/- mice recapitulated WMS, showing shorter long bones, brachydactyly, and thick skin. The hypertrophic zone of the growth plate in Adamts17-/- mice was shortened, with enhanced fibrillin-2 deposition, suggesting increased incorporation of fibrillin-2 into microfibrils. Comprehensive gene expression analysis of growth plates using laser microdissection and RNA sequencing indicated alteration of the bone morphogenetic protein (BMP) signaling pathway after Adamts17 knockout. Consistent with this, phospho-Smad1 levels were downregulated in the hypertrophic zone of the growth plate and in Adamts17-/- primary chondrocytes. Delayed terminal differentiation of Adamts17-/- chondrocytes, observed both in primary chondrocyte and primordial metatarsal cultures, and was prevented by BMP treatment. Our data indicated that Adamts17 is involved in skeletal formation by modulating BMP-Smad1/5/8 pathway, possibly through inhibiting the incorporation of fibrillin-2 into microfibrils. Our findings will contribute to further understanding of disease mechanisms and will facilitate the development of therapeutic interventions for WMS.


Assuntos
Proteínas ADAMTS/fisiologia , Proteínas Morfogenéticas Ósseas/metabolismo , Músculo Esquelético/crescimento & desenvolvimento , Transdução de Sinais , Proteínas ADAMTS/genética , Animais , Proteínas Morfogenéticas Ósseas/farmacologia , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Condrócitos/citologia , Condrócitos/metabolismo , Fibrilina-2/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microfibrilas/metabolismo , Músculo Esquelético/patologia , Pele/fisiopatologia , Proteína Smad1/metabolismo , Proteína Smad5/metabolismo , Proteína Smad8/metabolismo , Síndrome de Weill-Marchesani/metabolismo , Síndrome de Weill-Marchesani/patologia , Síndrome de Weill-Marchesani/veterinária
19.
Eur J Appl Physiol ; 119(8): 1725-1733, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31165241

RESUMO

PURPOSE: To compare the acute physiological responses of three different very low-volume cycling sessions (6 × 5 s, 3 × 30 s, and 3 × 60 s) and their dependence on age and training status. METHODS: Subjects were untrained young men (mean ± SD; age 22.3 ± 4.6 years, VO2peak 42.4 ± 5.5 ml/kg/min, n = 10), older untrained men (69.9 ± 6.3 years, 26.5 ± 7.6 ml/kg/min, n = 11), and endurance-trained cyclists (26.4 ± 9.4 years, 55.4 ± 6.6 ml/kg/min, n = 10). Maximal voluntary contraction (MVC) and electrically stimulated knee extension torque, and low-frequency fatigue, as ratio of stimulation torques at 20-100 Hz (P20/100), were measured only 24 h after exercise. Serum testosterone (Te) and blood lactate concentrations were measured only 1 h after exercise. RESULTS: All protocols increased the blood lactate concentration and decreased MVC and P20/100 in young men, but especially young untrained men. In old untrained men, 6 × 5 s decreased P20/100 but not MVC. Te increased after 3 × 30 s and 3 × 60 s in young untrained men and after 3 × 60 s in older untrained men. The increase in Te correlated with responses of blood lactate concentration, MVC, and P20/100 only in old untrained men. CONCLUSIONS: As little as 6 × 5 s all-out cycling induced fatigue in young and old untrained and endurance-trained cyclists. Slightly higher-volume sessions with longer intervals, however, suppressed contractile function more markedly and also transiently increased serum testosterone concentration in untrained men.


Assuntos
Envelhecimento/fisiologia , Treinamento Intervalado de Alta Intensidade , Fadiga Muscular , Testosterona/sangue , Adulto , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/crescimento & desenvolvimento , Músculo Esquelético/fisiologia , Aptidão Física
20.
Nat Cell Biol ; 21(6): 674-686, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31160712

RESUMO

In vertebrates, multipotent progenitors located in the pharyngeal mesoderm form cardiomyocytes and branchiomeric head muscles, but the dynamic gene expression programmes and mechanisms underlying cardiopharyngeal multipotency and heart versus head muscle fate choices remain elusive. Here, we used single-cell genomics in the simple chordate model Ciona to reconstruct developmental trajectories forming first and second heart lineages and pharyngeal muscle precursors and characterize the molecular underpinnings of cardiopharyngeal fate choices. We show that FGF-MAPK signalling maintains multipotency and promotes the pharyngeal muscle fate, whereas signal termination permits the deployment of a pan-cardiac programme, shared by the first and second heart lineages, to define heart identity. In the second heart lineage, a Tbx1/10-Dach pathway actively suppresses the first heart lineage programme, conditioning later cell diversity in the beating heart. Finally, cross-species comparisons between Ciona and the mouse evoke the deep evolutionary origins of cardiopharyngeal networks in chordates.


Assuntos
Ciona intestinalis/genética , Coração/crescimento & desenvolvimento , Músculos Faríngeos/crescimento & desenvolvimento , Proteínas com Domínio T/genética , Animais , Diferenciação Celular/genética , Linhagem da Célula/genética , Ciona intestinalis/crescimento & desenvolvimento , Fatores de Crescimento de Fibroblastos/genética , Regulação da Expressão Gênica no Desenvolvimento/genética , Genômica , Mesoderma/crescimento & desenvolvimento , Camundongos , Quinases de Proteína Quinase Ativadas por Mitógeno/genética , Músculo Esquelético/crescimento & desenvolvimento , Músculo Esquelético/metabolismo , Miócitos Cardíacos/citologia , Miócitos Cardíacos/metabolismo , Fatores de Transcrição/genética
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