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1.
Zool Res ; 42(5): 650-659, 2021 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-34472226

RESUMO

Phosphatidylserine (PS) is distributed asymmetrically in the plasma membrane of eukaryotic cells. Phosphatidylserine flippase (P4-ATPase) transports PS from the outer leaflet of the lipid bilayer to the inner leaflet of the membrane to maintain PS asymmetry. The ß subunit TMEM30A is indispensable for transport and proper function of P4-ATPase. Previous studies have shown that the ATP11A and TMEM30A complex is the molecular switch for myotube formation. However, the role of Tmem30a in skeletal muscle regeneration remains elusive. In the current study, Tmem30a was highly expressed in the tibialis anterior (TA) muscles of dystrophin-null ( mdx) mice and BaCl 2-induced muscle injury model mice. We generated a satellite cell (SC)-specific Tmem30a conditional knockout (cKO) mouse model to investigate the role of Tmem30a in skeletal muscle regeneration. The regenerative ability of cKO mice was evaluated by analyzing the number and diameter of regenerated SCs after the TA muscles were injured by BaCl 2-injection. Compared to the control mice, the cKO mice showed decreased Pax7 + and MYH3 + SCs, indicating diminished SC proliferation, and decreased expression of muscular regulatory factors (MYOD and MYOG), suggesting impaired myoblast proliferation in skeletal muscle regeneration. Taken together, these results demonstrate the essential role of Tmem30a in skeletal muscle regeneration.


Assuntos
Proteínas de Membrana/metabolismo , Músculo Esquelético/fisiologia , Regeneração/fisiologia , Células Satélites de Músculo Esquelético/metabolismo , Animais , Proliferação de Células , Distrofina/genética , Distrofina/metabolismo , Antagonistas de Estrogênios/toxicidade , Regulação da Expressão Gênica/fisiologia , Genótipo , Proteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos mdx , Camundongos Knockout , Músculo Esquelético/efeitos dos fármacos , Proteína MyoD/genética , Proteína MyoD/metabolismo , Miogenina/genética , Miogenina/metabolismo , Cadeias Pesadas de Miosina/genética , Cadeias Pesadas de Miosina/metabolismo , Fator de Transcrição PAX7/genética , Fator de Transcrição PAX7/metabolismo , Regeneração/genética , Tamoxifeno/toxicidade
2.
J Int Soc Sports Nutr ; 18(1): 60, 2021 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-34503541

RESUMO

BACKGROUND: Numerous studies have demonstrated the efficacy of creatine supplementation for improvements in exercise performance. Few studies, however, have examined the effects of phosphocreatine supplementation on exercise performance. Furthermore, while polyphenols have antioxidant and anti-inflammatory properties, little is known regarding the influence of polyphenol supplementation on muscular strength, power, and endurance. Thus, the purpose of the present study was to compare the effects of 28 days of supplementation with phosphocreatine disodium salts plus blueberry extract (PCDSB), creatine monohydrate (CM), and placebo on measures of muscular strength, power, and endurance. METHODS: Thirty-three men were randomly assigned to consume either PCDSB, CM, or placebo for 28 days. Peak torque (PT), average power (AP), and percent decline for peak torque (PT%) and average power (AP%) were assessed from a fatigue test consisting of 50 maximal, unilateral, isokinetic leg extensions at 180°·s- 1 before and after the 28 days of supplementation. Individual responses were assessed to examine the proportion of subjects that exceeded a minimal important difference (MID). RESULTS: The results demonstrated significant (p < 0.05) improvements in PT for the PCDSB and CM groups from pre- (99.90 ± 22.47 N·m and 99.95 ± 22.50 N·m, respectively) to post-supplementation (119.22 ± 29.87 N·m and 111.97 ± 24.50 N·m, respectively), but no significant (p = 0.112) change for the placebo group. The PCDSB and CM groups also exhibited significant improvements in AP from pre- (140.18 ± 32.08 W and 143.42 ± 33.84 W, respectively) to post-supplementation (170.12 ± 42.68 W and 159.78 ± 31.20 W, respectively), but no significant (p = 0.279) change for the placebo group. A significantly (p < 0.05) greater proportion of subjects in the PCDSB group exceeded the MID for PT compared to the placebo group, but there were no significant (p > 0.05) differences in the proportion of subjects exceeding the MID between the CM and placebo groups or between the CM and PCDSB groups. CONCLUSIONS: These findings indicated that for the group mean responses, 28 days of supplementation with both PCDSB and CM resulted in increases in PT and AP. The PCDSB, however, may have an advantage over CM when compared to the placebo group for the proportion of individuals that respond favorably to supplementation with meaningful increases in muscular strength.


Assuntos
Força Muscular/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Fosfocreatina/farmacologia , Resistência Física/efeitos dos fármacos , Extratos Vegetais/farmacologia , Mirtilos Azuis (Planta)/química , Creatina , Suplementos Nutricionais , Método Duplo-Cego , Humanos , Masculino , Torque , Adulto Jovem
3.
Nutrients ; 13(8)2021 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-34444975

RESUMO

This review evaluated the effects of milk-based protein supplementation on resistance training (RT)-induced gains in lean body mass or fat free mass (LBM/FFM) and muscle strength for older adults. A systematic search of PubMed, Scopus and EBSCOhost/SPORTDiscus was conducted. Eligibility criteria: Randomized controlled trials comparing all types of milk-based protein supplements with control supplements for the training older adults at mean age ≥ 60 y. Twenty studies were included in the qualitative synthesis, whilst seventeen studies were included in the quantitative synthesis. A dose of 10-15 g of milk protein supplementation was sufficient to augment RT-induced LBM/FFM. Intriguingly, four out of five studies show negative effect of whey protein supplementation at the same dose range (or even higher) compared with control supplementation (-0.49 kg, 95% CI: -0.69, -0.29, I2 = 14%, Z = 4.82, p < 0.001). For milk-based protein supplementation, RT-induced improvements in muscle strength were observed only when the protein doses ≥22 g (+0.66 kg, 95% CI: 0.07, 1.25, I2 = 0%, Z = 2.18, p = 0.03). Conclusion: Milk protein is superior to whey protein in enhancing RT-induced LBM/FFM gains for older adults. Optimal daily protein intake can dilute the protein supplementation effect.


Assuntos
Composição Corporal/efeitos dos fármacos , Suplementos Nutricionais , Proteínas do Leite/farmacologia , Força Muscular/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Treinamento de Força , Idoso , Idoso de 80 Anos ou mais , Compartimentos de Líquidos Corporais/efeitos dos fármacos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas do Soro do Leite/farmacologia
4.
Nutrients ; 13(8)2021 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-34445003

RESUMO

Creatine has been considered an effective ergogenic aid for several decades; it can help athletes engaged in a variety of sports and obtain performance gains. Creatine supplementation increases muscle creatine stores; several factors have been identified that may modify the intramuscular increase and subsequent performance benefits, including baseline muscle Cr content, type II muscle fibre content and size, habitual dietary intake of Cr, aging, and exercise. Timing of creatine supplementation in relation to exercise has recently been proposed as an important consideration to optimise muscle loading and performance gains, although current consensus is lacking regarding the ideal ingestion time. Research has shifted towards comparing creatine supplementation strategies pre-, during-, or post-exercise. Emerging evidence suggests greater benefits when creatine is consumed after exercise compared to pre-exercise, although methodological limitations currently preclude solid conclusions. Furthermore, physiological and mechanistic data are lacking, in regard to claims that the timing of creatine supplementation around exercise moderates gains in muscle creatine and exercise performance. This review discusses novel scientific evidence on the timing of creatine intake, the possible mechanisms that may be involved, and whether the timing of creatine supplementation around exercise is truly a real concern.


Assuntos
Creatina/administração & dosagem , Suplementos Nutricionais , Exercício Físico/fisiologia , Músculo Esquelético/efeitos dos fármacos , Substâncias para Melhoria do Desempenho/administração & dosagem , Creatina/efeitos adversos , Creatina/metabolismo , Suplementos Nutricionais/efeitos adversos , Esquema de Medicação , Feminino , Humanos , Masculino , Músculo Esquelético/metabolismo , Substâncias para Melhoria do Desempenho/efeitos adversos , Substâncias para Melhoria do Desempenho/metabolismo , Fatores de Tempo , Resultado do Tratamento
5.
Nutrients ; 13(7)2021 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-34371824

RESUMO

Delayed-onset muscle soreness (DOMS) is associated with increases in acute inflammatory and biochemical markers, muscle swelling, pain, and reduced functional performance. This study aimed to investigate the preventative effects of crocodile blood supplementation on DOMS induced by eccentric exercise. Sixteen healthy males were randomly allocated to either a crocodile blood (CB, n = 8) or a placebo (PL, n = 8) treatment. Participants receiving the CB treatment consumed four capsules of freeze-dried CB powder (1 g day-1) over 18 days. Participants receiving the other treatment were administered a placebo over the same period. An eccentric exercise protocol was performed, and functional performance, visual analogue scale (VAS)-measured pain, knee range of movement (ROM), thigh circumference (swelling), and cytokines, enzymes, and biochemical parameters were assessed immediately after exercise as well as after 24 h, 48 h, and 72 h. CB supplementation could significantly maintain maximum voluntary isometric contraction (MVIC) at 24 h (p = 0.001) and 48 h after exercise (p = 0.001) when comparing values at different times for the CB group. In the CB group, thigh circumference decreased only immediately after eccentric exercise (p = 0.031) in comparison with pre-eccentric exercise values. An 18-day supplementation (1 g day-1) of crocodile blood does aid in the maintenance of functional performance and muscle swelling after eccentric exercise. Our data indicate that 1 g day-1 of crocodile blood supplementation should be safe for human consumption.


Assuntos
Jacarés e Crocodilos/sangue , Suplementos Nutricionais , Exercício Físico/fisiologia , Doenças Musculares/prevenção & controle , Mialgia/prevenção & controle , Animais , Biomarcadores/análise , Método Duplo-Cego , Edema/etiologia , Edema/fisiopatologia , Edema/prevenção & controle , Voluntários Saudáveis , Humanos , Contração Isométrica/efeitos dos fármacos , Masculino , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/fisiopatologia , Doenças Musculares/etiologia , Doenças Musculares/fisiopatologia , Mialgia/etiologia , Mialgia/fisiopatologia , Medição da Dor , Desempenho Físico Funcional , Amplitude de Movimento Articular/efeitos dos fármacos , Adulto Jovem
6.
Nutrients ; 13(7)2021 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-34371806

RESUMO

BACKGROUND AND AIM: Sarcopenia is considered an important risk factor for morbidity and mortality in liver cirrhosis. Beta-hydroxy-beta-methylbutyrate (HMB) has the potential to increase muscle mass and performance by stimulating protein synthesis and reducing muscle catabolism. The present study aimed at evaluating the effect of HMB supplementation on muscle mass and function in patients with liver cirrhosis. Changes in frailty during the study were also estimated, and the safety of HMB supplementation was verified. METHODS: This is a randomized, single-blind, placebo-controlled pilot trial. Twenty-four patients (14 HMB and 10 placebo) affected by liver cirrhosis were enrolled in the study. Each patient received dedicated counseling, which included nutrition and physical activity recommendations for chronic liver disease patients. Patients were randomized to receive 3 g/day of HMB or placebo (sorbitol powder) for 12 consecutive weeks. A diet interview, anthropometry, electrical bioimpedance analysis (BIA), quadriceps ultrasound, physical performance battery, Liver Frailty Index (LFI), and cognitive tests were completed at enrolment (T0), at 12 weeks (T1), and 24 weeks after enrolment (T2). RESULTS: At baseline, the two groups were similar in demography, severity of liver disease, muscle mass, muscle function, and cognitive tests. LFI at baseline was higher in patients in the HMB group vs. those in the placebo group (4.1 ± 0.4 vs. 3.4 ± 0.6, p < 0.01). After treatment, a statistically significant increase in muscle function was seen in the HMB group (chair stand test: 14.2 ± 5 s vs. 11.7 ± 2.6 s, p < 0.05; six-minute walk test: 361.8 ± 68 m vs. 409.4 ± 58 m, p < 0.05). Quadriceps muscle mass measured by ultrasound also increased (4.9 ± 1.8 vs. 5.4 ± 1.8 mm, p < 0.05) after HMB, while LFI decreased (4.1 ± 0.4 vs. 3.7 ± 0.4, p < 0.05). HMB was well tolerated by patients, and no adverse events were documented. CONCLUSIONS: Our study suggests the efficacy of 12-week beta-hydroxy-beta-methylbutyrate supplementation in promoting improvements in muscle performance in compensated cirrhotic patients. LFI was also ameliorated. Further studies with a greater number of patients are required to reinforce this hypothesis.


Assuntos
Suplementos Nutricionais , Cirrose Hepática/terapia , Força Muscular/efeitos dos fármacos , Sarcopenia/prevenção & controle , Valeratos/administração & dosagem , Antropometria , Impedância Elétrica , Exercício Físico/fisiologia , Feminino , Fragilidade/etiologia , Fragilidade/prevenção & controle , Humanos , Cirrose Hepática/complicações , Cirrose Hepática/fisiopatologia , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/efeitos dos fármacos , Projetos Piloto , Sarcopenia/etiologia , Método Simples-Cego , Resultado do Tratamento
7.
Nutrients ; 13(7)2021 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-34371813

RESUMO

Creatine monohydrate (CrM) supplementation has been shown to improve body composition and muscle strength when combined with resistance training (RT); however, no study has evaluated the combination of this nutritional strategy with cluster-set resistance training (CS-RT). The purpose of this pilot study was to evaluate the effects of CrM supplementation during a high-protein diet and a CS-RT program on lower-limb fat-free mass (LL-FFM) and muscular strength. Twenty-three resistance-trained men (>2 years of training experience, 26.6 ± 8.1 years, 176.3 ± 6.8 cm, 75.6 ± 8.9 kg) participated in this study. Subjects were randomly allocated to a CS-RT+CrM (n = 8), a CS-RT (n = 8), or a control group (n = 7). The CS-RT+CrM group followed a CrM supplementation protocol with 0.1 g·kg-1·day-1 over eight weeks. Two sessions per week of lower-limb CS-RT were performed. LL-FFM corrected for fat-free adipose tissue (dual-energy X-ray absorptiometry) and muscle strength (back squat 1 repetition maximum (SQ-1RM) and countermovement jump (CMJ)) were measured pre- and post-intervention. Significant improvements were found in whole-body fat mass, fat percentage, LL-fat mass, LL-FFM, and SQ-1RM in the CS-RT+CrM and CS-RT groups; however, larger effect sizes were obtained in the CS-RT+CrM group regarding whole body FFM (0.64 versus 0.16), lower-limb FFM (0.62 versus 0.18), and SQ-1RM (1.23 versus 0.75) when compared to the CS-RT group. CMJ showed a significant improvement in the CS-RT+CrM group with no significant changes in CS-RT or control groups. No significant differences were found between groups. Eight weeks of CrM supplementation plus a high-protein diet during a CS-RT program has a higher clinical meaningfulness on lower-limb body composition and strength-related variables in trained males than CS-RT alone. Further research might study the potential health and therapeutic effects of this nutrition and exercise strategy.


Assuntos
Composição Corporal/efeitos dos fármacos , Creatina/farmacologia , Força Muscular/efeitos dos fármacos , Substâncias para Melhoria do Desempenho/farmacologia , Treinamento de Força/métodos , Absorciometria de Fóton , Tecido Adiposo/diagnóstico por imagem , Adulto , Dieta Rica em Proteínas , Suplementos Nutricionais , Exercício Físico/fisiologia , Humanos , Extremidade Inferior/fisiologia , Masculino , Músculo Esquelético/efeitos dos fármacos , Projetos Piloto , Adulto Jovem
8.
Molecules ; 26(16)2021 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-34443483

RESUMO

Skeletal muscle atrophy is the decrease in muscle mass and strength caused by reduced protein synthesis/accelerated protein degradation. Various conditions, such as denervation, disuse, aging, chronic diseases, heart disease, obstructive lung disease, diabetes, renal failure, AIDS, sepsis, cancer, and steroidal medications, can cause muscle atrophy. Mechanistically, inflammation, oxidative stress, and mitochondrial dysfunction are among the major contributors to muscle atrophy, by modulating signaling pathways that regulate muscle homeostasis. To prevent muscle catabolism and enhance muscle anabolism, several natural and synthetic compounds have been investigated. Recently, polyphenols (i.e., natural phytochemicals) have received extensive attention regarding their effect on muscle atrophy because of their potent antioxidant and anti-inflammatory properties. Numerous in vitro and in vivo studies have reported polyphenols as strongly effective bioactive molecules that attenuate muscle atrophy and enhance muscle health. This review describes polyphenols as promising bioactive molecules that impede muscle atrophy induced by various proatrophic factors. The effects of each class/subclass of polyphenolic compounds regarding protection against the muscle disorders induced by various pathological/physiological factors are summarized in tabular form and discussed. Although considerable variations in antiatrophic potencies and mechanisms were observed among structurally diverse polyphenolic compounds, they are vital factors to be considered in muscle atrophy prevention strategies.


Assuntos
Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Músculo Esquelético/efeitos dos fármacos , Atrofia Muscular/tratamento farmacológico , Atrofia Muscular/metabolismo , Compostos Fitoquímicos/farmacologia , Polifenóis/farmacologia , Animais , Anti-Inflamatórios/efeitos adversos , Anti-Inflamatórios/química , Anti-Inflamatórios/uso terapêutico , Antioxidantes/efeitos adversos , Antioxidantes/química , Antioxidantes/uso terapêutico , Humanos , Compostos Fitoquímicos/efeitos adversos , Compostos Fitoquímicos/química , Compostos Fitoquímicos/uso terapêutico , Polifenóis/efeitos adversos , Polifenóis/química , Polifenóis/uso terapêutico , Transdução de Sinais/efeitos dos fármacos
9.
Int J Mol Sci ; 22(16)2021 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-34445567

RESUMO

S1P is the final product of sphingolipid metabolism, which interacts with five widely expressed GPCRs (S1P1-5). Increasing numbers of studies have indicated the importance of S1P3 in various pathophysiological processes. Recently, we have identified a pepducin (compound KRX-725-II) acting as an S1P3 receptor antagonist. Here, aiming to optimize the activity and selectivity profile of the described compound, we have synthesized a series of derivatives in which Tyr, in position 4, has been substituted with several natural aromatic and unnatural aromatic and non-aromatic amino acids. All the compounds were evaluated for their ability to inhibit vascular relaxation induced by KRX-725 (as S1P3 selective pepducin agonist) and KRX-722 (an S1P1-selective pepducin agonist). Those selective towards S1P3 (compounds V and VII) were also evaluated for their ability to inhibit skeletal muscle fibrosis. Finally, molecular dynamics simulations were performed to derive information on the preferred conformations of selective and unselective antagonists.


Assuntos
Peptídeos Penetradores de Células/farmacologia , Fibrose/tratamento farmacológico , Músculo Esquelético/efeitos dos fármacos , Doenças Musculares/tratamento farmacológico , Mioblastos/efeitos dos fármacos , Fragmentos de Peptídeos/farmacologia , Receptores de Esfingosina-1-Fosfato/antagonistas & inibidores , Animais , Fibrose/metabolismo , Fibrose/patologia , Masculino , Camundongos , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Doenças Musculares/metabolismo , Doenças Musculares/patologia , Mioblastos/metabolismo , Mioblastos/patologia , Receptores de Lisoesfingolipídeo
10.
Int J Mol Sci ; 22(16)2021 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-34445295

RESUMO

Skeletal muscle is affected in experimental autoimmune encephalomyelitis (EAE), which is a model of multiple sclerosis that produces changes including muscle atrophy; histological features of neurogenic involvement, and increased oxidative stress. In this study, we aimed to evaluate the therapeutic effects of transcranial magnetic stimulation (TMS) on the involvement of rat skeletal muscle and to compare them with those produced by natalizumab (NTZ). EAE was induced by injecting myelin oligodendrocyte glycoprotein (MOG) into Dark Agouti rats. Both treatments, NTZ and TMS, were implemented from day 15 to day 35. Clinical severity was studied, and after sacrifice, the soleus and extensor digitorum longus muscles were extracted for subsequent histological and biochemical analysis. The treatment with TMS and NTZ had a beneficial effect on muscle involvement in the EAE model. There was a clinical improvement in functional motor deficits, atrophy was attenuated, neurogenic muscle lesions were reduced, and the level of oxidative stress biomarkers was lower in both treatment groups. Compared to NTZ, the best response was obtained with TMS for all the parameters analyzed. The myoprotective effect of TMS was higher than that of NTZ. Thus, the use of TMS may be an effective strategy to reduce muscle involvement in multiple sclerosis.


Assuntos
Encefalomielite Autoimune Experimental/terapia , Atrofia Muscular/prevenção & controle , Estimulação Magnética Transcraniana , Animais , Contagem de Células , Encefalomielite Autoimune Experimental/induzido quimicamente , Encefalomielite Autoimune Experimental/patologia , Encefalomielite Autoimune Experimental/fisiopatologia , Masculino , Fibras Musculares Esqueléticas/efeitos dos fármacos , Fibras Musculares Esqueléticas/patologia , Fibras Musculares Esqueléticas/fisiologia , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/patologia , Músculo Esquelético/fisiopatologia , Atrofia Muscular/fisiopatologia , Glicoproteína Mielina-Oligodendrócito , Natalizumab/farmacologia , Ratos
11.
FASEB J ; 35(9): e21861, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34416029

RESUMO

Duchenne muscular dystrophy (DMD) is an intractable genetic disease associated with progressive skeletal muscle weakness and degeneration. Recently, it was reported that intraperitoneal injections of ketone bodies partially ameliorated muscular dystrophy by increasing satellite cell (SC) proliferation. Here, we evaluated whether a ketogenic diet (KD) with medium-chain triglycerides (MCT-KD) could alter genetically mutated DMD in model rats. We found that the MCT-KD significantly increased muscle strength and fiber diameter in these rats. The MCT-KD significantly suppressed the key features of DMD, namely, muscle necrosis, inflammation, and subsequent fibrosis. Immunocytochemical analysis revealed that the MCT-KD promoted the proliferation of muscle SCs, suggesting enhanced muscle regeneration. The muscle strength of DMD model rats fed with MCT-KD was significantly improved even at the age of 9 months. Our findings suggested that the MCT-KD ameliorates muscular dystrophy by inhibiting myonecrosis and promoting the proliferation of muscle SCs. As far as we can ascertain, this is the first study to apply a functional diet as therapy for DMD in experimental animals. Further studies are needed to elucidate the underlying mechanisms of the MCT-KD-induced improvement of DMD.


Assuntos
Dieta Cetogênica , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/fisiologia , Distrofia Muscular de Duchenne/dietoterapia , Distrofia Muscular de Duchenne/fisiopatologia , Triglicerídeos/química , Triglicerídeos/farmacologia , Animais , Peso Corporal/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Modelos Animais de Doenças , Progressão da Doença , Feminino , Fibrose/dietoterapia , Fibrose/patologia , Inflamação/dietoterapia , Inflamação/patologia , Cetonas/sangue , Cetose , Masculino , Músculo Esquelético/patologia , Músculo Esquelético/fisiopatologia , Distrofia Muscular de Duchenne/patologia , Necrose/dietoterapia , Necrose/patologia , Ratos , Células Satélites de Músculo Esquelético/citologia , Células Satélites de Músculo Esquelético/efeitos dos fármacos , Triglicerídeos/uso terapêutico
12.
FASEB J ; 35(9): e21862, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34416035

RESUMO

Loss of muscle mass and strength after disuse followed by impaired muscle recovery commonly occurs with aging. Metformin (MET) and leucine (LEU) individually have shown positive effects in skeletal muscle during atrophy conditions but have not been evaluated in combination nor tested as a remedy to enhance muscle recovery following disuse atrophy in aging. The purpose of this study was to determine if a dual treatment of metformin and leucine (MET + LEU) would prevent disuse-induced atrophy and/or promote muscle recovery in aged mice and if these muscle responses correspond to changes in satellite cells and collagen remodeling. Aged mice (22-24 months) underwent 14 days of hindlimb unloading (HU) followed by 7 or 14 days of reloading (7 or 14 days RL). MET, LEU, or MET + LEU was administered via drinking water and were compared to Vehicle (standard drinking water) and ambulatory baseline. We observed that during HU, MET + LEU resolved whole body grip strength and soleus muscle specific force decrements caused by HU. Gastrocnemius satellite cell abundance was increased with MET + LEU treatment but did not alter muscle size during disuse or recovery conditions. Moreover, MET + LEU treatment alleviated gastrocnemius collagen accumulation caused by HU and increased collagen turnover during 7 and 14 days RL driven by a decrease in collagen IV content. Transcriptional pathway analysis revealed that MET + LEU altered muscle hallmark pathways related to inflammation and myogenesis during HU. Together, the dual treatment of MET and LEU was able to increase muscle function, satellite cell content, and reduce collagen accumulation, thus improving muscle quality during disuse and recovery in aging.


Assuntos
Envelhecimento , Colágeno/metabolismo , Leucina/uso terapêutico , Metformina/uso terapêutico , Músculo Esquelético/efeitos dos fármacos , Atrofia Muscular/prevenção & controle , Células Satélites de Músculo Esquelético/efeitos dos fármacos , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Peso Corporal/efeitos dos fármacos , Fibrose/tratamento farmacológico , Elevação dos Membros Posteriores , Imunoglobulina G/análise , Leucina/farmacologia , Masculino , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Metformina/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Desenvolvimento Muscular/efeitos dos fármacos , Fibras Musculares Esqueléticas/efeitos dos fármacos , Força Muscular/efeitos dos fármacos , Músculo Esquelético/citologia , Músculo Esquelético/patologia , Atrofia Muscular/patologia , Tamanho do Órgão/efeitos dos fármacos , RNA-Seq , Células Satélites de Músculo Esquelético/citologia , Células Satélites de Músculo Esquelético/patologia , Transdução de Sinais/efeitos dos fármacos
13.
Int J Mol Sci ; 22(15)2021 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-34361076

RESUMO

The weight of skeletal muscle accounts for approximately 40% of the whole weight in a healthy individual, and the normal metabolism and motor function of the muscle are indispensable for healthy life. In addition, the skeletal muscle of the maxillofacial region plays an important role not only in eating and swallowing, but also in communication, such as facial expressions and conversations. In recent years, skeletal muscle atrophy has received worldwide attention as a serious health problem. However, the mechanism of skeletal muscle atrophy that has been clarified at present is insufficient, and a therapeutic method against skeletal muscle atrophy has not been established. This review provides views on the importance of skeletal muscle in the maxillofacial region and explains the differences between skeletal muscles in the maxillofacial region and other regions. We summarize the findings to change in gene expression in muscle remodeling and emphasize the advantages and disadvantages of denervation-induced skeletal muscle atrophy model. Finally, we discuss the newly discovered beneficial effects of natural compounds on skeletal muscle atrophy.


Assuntos
Produtos Biológicos/farmacologia , Denervação/efeitos adversos , Músculo Esquelético/efeitos dos fármacos , Atrofia Muscular/prevenção & controle , Animais , Humanos , Músculo Esquelético/patologia , Atrofia Muscular/etiologia , Atrofia Muscular/patologia
14.
Nutrients ; 13(6)2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-34203642

RESUMO

Based on the Digestible Indispensable Amino Acid Score (DIAAS), egg white protein (EGG) has an excellent score, comparable to that of whey protein but with a lower amount of leucine. We examined the effect of EGG feeding on rat skeletal muscle gain in comparison to that of two common animal-derived protein sources: casein (CAS) and whey (WHE). To explore the full potential of EGG, this was examined in clenbuterol-treated young rats. Furthermore, we focused on leucine-associated anabolic signaling in response to EGG after single-dose ingestion and chronic ingestion, as well as clenbuterol treatment. Because EGG is an arginine-rich protein source, a portion of the experiment was repeated with diets containing equal amounts of arginine. We demonstrated that EGG feeding accelerates skeletal muscle gain under anabolism-dominant conditions more efficiently than CAS and WHE and this stronger effect with EGG is not dependent on the arginine-rich composition of the protein source. We also demonstrated that the plausible mechanism of the stronger muscle-gain effect with EGG is not detectable in the mechanistic target of rapamycin (mTOR) or insulin signaling under our experimental conditions. We conclude that EGG may have a superior efficiency in muscle gain compared to other common animal-based proteins.


Assuntos
Clembuterol/metabolismo , Clembuterol/farmacologia , Dieta , Proteínas do Ovo/administração & dosagem , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Animais , Arginina , Caseínas/metabolismo , Ingestão de Alimentos , Insulina/metabolismo , Leucina , Masculino , Músculo Esquelético/crescimento & desenvolvimento , Ratos , Ratos Wistar , Transdução de Sinais , Serina-Treonina Quinases TOR , Proteínas do Soro do Leite
15.
Molecules ; 26(13)2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34279373

RESUMO

Fatty acid content and lipid oxidation products were compared in chicken breast and leg meats derived from birds fed on animal-fat- and vegetable-oil-based diets, supplemented with ginseng prong powder. The first experiment examined polyunsaturated fatty acid (PUFA) content and the formation of primary and secondary lipid oxidation products in meats stored at refrigeration temperatures (4 °C) for up to 10 days, while the second experiment examined similar changes in the poultry meats when frozen stored at -18 °C, for up to six months. Results showed that initial lipid hydroperoxide concentrations increased in both breast and leg meat within the first week of refrigerated storage and also was ongoing during the first three to four months of frozen storage. A higher (p < 0.05) PUFA content in leg meat, especially in broilers fed a vegetable-oil-blended diet, corresponded to greater tendency for generation of primary lipid oxidation products after refrigerated and frozen storage (p < 0.05). The inclusion of powdered ginseng prong in broiler diets significantly inhibited (p < 0.05) secondary lipid oxidation products (e.g., malonaldehyde [MDA]) formation in both stored leg and breast meat, compared to controls. Significant interactions (p < 0.05) were obtained for storage time and inclusion of ginseng against production of primary and secondary lipid oxidation in broiler breast and leg meats from broilers fed PUFA-containing diets. We conclude that including ginseng prong in broiler growing diets represents a viable strategy to control lipid oxidation in refrigerated/cold-stored meat products.


Assuntos
Galinhas/metabolismo , Suplementos Nutricionais , Peroxidação de Lipídeos , Carne/normas , Panax/química , Extratos Vegetais/farmacologia , Animais , Ácidos Graxos Ômega-3/metabolismo , Alimentos Congelados/normas , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Extratos Vegetais/administração & dosagem
16.
Am J Physiol Regul Integr Comp Physiol ; 321(3): R385-R395, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34259041

RESUMO

Exercise intolerance is a hallmark symptom of cardiovascular disease and likely occurs via enhanced activation of muscle metaboreflex-induced vasoconstriction of the heart and active skeletal muscle which, thereby limits cardiac output and peripheral blood flow. Muscle metaboreflex vasoconstrictor responses occur via activation of metabolite-sensitive afferent fibers located in ischemic active skeletal muscle, some of which express transient receptor potential vanilloid 1 (TRPV1) cation channels. Local cardiac and intrathecal administration of an ultrapotent noncompetitive, dominant negative agonist resiniferatoxin (RTX) can ablate these TRPV1-sensitive afferents. This technique has been used to attenuate cardiac sympathetic afferents and nociceptive pain. We investigated whether intrathecal administration (L4-L6) of RTX (2 µg/kg) could chronically attenuate subsequent muscle metaboreflex responses elicited by reductions in hindlimb blood flow during mild exercise (3.2 km/h) in chronically instrumented conscious canines. RTX significantly attenuated metaboreflex-induced increases in mean arterial pressure (27 ± 5.0 mmHg vs. 6 ± 8.2 mmHg), cardiac output (1.40 ± 0.2 L/min vs. 0.28 ± 0.1 L/min), and stroke work (2.27 ± 0.2 L·mmHg vs. 1.01 ± 0.2 L·mmHg). Effects were maintained until 78 ± 14 days post-RTX at which point the efficacy of RTX injection was tested by intra-arterial administration of capsaicin (20 µg/kg). A significant reduction in the mean arterial pressure response (+45.7 ± 6.5 mmHg pre-RTX vs. +19.7 ± 3.1 mmHg post-RTX) was observed. We conclude that intrathecal administration of RTX can chronically attenuate the muscle metaboreflex and could potentially alleviate enhanced sympatho-activation observed in cardiovascular disease states.


Assuntos
Débito Cardíaco/efeitos dos fármacos , Diterpenos/farmacologia , Membro Posterior/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Animais , Pressão Arterial/efeitos dos fármacos , Débito Cardíaco/fisiologia , Diterpenos/administração & dosagem , Cães , Coração/efeitos dos fármacos , Coração/fisiopatologia , Membro Posterior/fisiopatologia , Isquemia/fisiopatologia , Contração Muscular/efeitos dos fármacos , Contração Muscular/fisiologia , Fluxo Sanguíneo Regional/efeitos dos fármacos , Sistema Nervoso Simpático/efeitos dos fármacos , Sistema Nervoso Simpático/fisiopatologia , Vasoconstrição/fisiologia
17.
Nutrients ; 13(6)2021 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-34199375

RESUMO

Elderly women exhibit a high risk of type 2 diabetes (T2D), but no definitive data exist about the possible role of postmenopausal increases in visceral adiposity, the loss of lean body mass, or decreases in the sum of the lean mass of arms and legs (appendicular skeletal muscle mass (ASMM)). This retrospective, longitudinal study investigated whether body composition (bioelectrical impedance analysis) predicted the development of impaired fasting glucose (IFG) or T2D in a cohort of 159 elderly women (age: 71 ± 5 years, follow-up: 94 months) from southern Italy (Clinical Nutrition and Geriatric Units of the "Mater Domini" University Hospital in Catanzaro, Calabria region, and the "P. Giaccone "University Hospital in Palermo, Sicily region). Sarcopenia was defined in a subgroup of 128 women according to the EWGSOP criteria as the presence of low muscle strength (handgrip strength <16 kg) plus low muscle mass (reported as appendicular skeletal muscle mass <15 kg). Participants with a low ASMM had a higher IFG/T2D incidence than those with a normal ASMM (17% vs. 6%, p-adjusted = 0.044); this finding was independent of BMI, fat mass, waist circumference, and habitual fat intake (OR = 3.81, p = 0.034). A higher incidence of IFG/T2D was observed in the subgroup with sarcopenia than those without sarcopenia (33% vs. 7%, p-adjusted = 0.005) independent of BMI and fat mass (OR = 6.75, p = 0.007). In conclusion, this study demonstrates that elderly women with low ASMM had a higher probability of developing IFG/T2D. Further studies are needed to confirm these results in men and in other age groups.


Assuntos
Diabetes Mellitus Tipo 2 , Jejum , Glucose , Músculo Esquelético/efeitos dos fármacos , Sarcopenia/fisiopatologia , Idoso , Composição Corporal , Índice de Massa Corporal , Estudos de Coortes , Ingestão de Alimentos , Feminino , Força da Mão , Humanos , Itália , Estudos Longitudinais , Força Muscular , Doenças Musculares , Estudos Retrospectivos , Sicília
18.
Nutrients ; 13(6)2021 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-34199420

RESUMO

Creatine supplementation in conjunction with resistance training (RT) augments gains in lean tissue mass and strength in aging adults; however, there is a large amount of heterogeneity between individual studies that may be related to creatine ingestion strategies. Therefore, the purpose of this review was to (1) perform updated meta-analyses comparing creatine vs. placebo (independent of dosage and frequency of ingestion) during a resistance training program on measures of lean tissue mass and strength, (2) perform meta-analyses examining the effects of different creatine dosing strategies (lower: ≤5 g/day and higher: >5 g/day), with and without a creatine-loading phase (≥20 g/day for 5-7 days), and (3) perform meta-analyses determining whether creatine supplementation only on resistance training days influences measures of lean tissue mass and strength. Overall, creatine (independent of dosing strategy) augments lean tissue mass and strength increase from RT vs. placebo. Subanalyses showed that creatine-loading followed by lower-dose creatine (≤5 g/day) increased chest press strength vs. placebo. Higher-dose creatine (>5 g/day), with and without a creatine-loading phase, produced significant gains in leg press strength vs. placebo. However, when studies involving a creatine-loading phase were excluded from the analyses, creatine had no greater effect on chest press or leg press strength vs. placebo. Finally, creatine supplementation only on resistance training days significantly increased measures of lean tissue mass and strength vs. placebo.


Assuntos
Envelhecimento/efeitos dos fármacos , Creatina/administração & dosagem , Ingestão de Alimentos/efeitos dos fármacos , Idoso , Suplementos Nutricionais , Alimentos Fortificados , Humanos , Força Muscular/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Treinamento de Força , Levantamento de Peso
19.
Nutrients ; 13(6)2021 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-34204359

RESUMO

Scientific evidence supports the role of L-glutamine in improving immune function. This could suggest a possible role of L-glutamine in recovery after intense exercise. To this end, the present report aimed to study if oral L-glutamine supplementation could attenuate muscle damage in a group of players of a mainly eccentric sport discipline such as basketball. Participants (n = 12) were supplemented with 6 g/day of glutamine (G group) or placebo (P group) for 40 days in a crossover study design (20 days with glutamine + 20 days with placebo and vice versa). Blood samples were obtained at the beginning and at the end of each period and markers from exercise-induced muscle damage were determined. The glutamine supplemented group displayed significantly low values of aspartate transaminase, creatine kinase and myoglobin in blood, suggesting less muscle damage compared to the placebo. In addition, adrenocorticotropic hormone levels were lower in the glutamine supplemented group than in the placebo. As a result, the circulating cortisol levels did not increase at the end of the study in the glutamine supplemented group. Altogether, the results indicate that glutamine could help attenuate exercise-induced muscle damage in sport disciplines with predominantly eccentric actions.


Assuntos
Basquetebol , Biomarcadores/sangue , Suplementos Nutricionais , Glutamina/administração & dosagem , Músculo Esquelético/efeitos dos fármacos , Adulto , Aspartato Aminotransferases/sangue , Creatina Quinase/sangue , Diástase Muscular/tratamento farmacológico , Método Duplo-Cego , Exercício Físico/fisiologia , Humanos , Mioglobina , Adulto Jovem
20.
Int J Mol Sci ; 22(12)2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-34203705

RESUMO

The origin of the Oxytocin/Vasopressin system dates back about 600 million years. Oxytocin (Oxt) together with Vasopressin (VP) regulate a diversity of physiological functions that are important for osmoregulation, reproduction, metabolism, and social behavior. Oxt/VP-like peptides have been identified in several invertebrate species and they are functionally related across the entire animal kingdom. Functional conservation enables future exploitation of invertebrate models to study Oxt's functions not related to pregnancy and the basic mechanisms of central Oxt/VP signaling. Specifically, Oxt is well known for its effects on uteri contractility and milk ejection as well as on metabolism and energy homeostasis. Moreover, the striking evidence that Oxt is linked to energy regulation is that Oxt- and Oxytocin receptor (Oxtr)-deficient mice show late onset obesity. Interestingly Oxt-/- or Oxtr-/- mice develop weight gain without increasing food intake, suggesting that a lack of Oxt reduce metabolic rate. Oxt is expressed in a diversity of skeletal muscle phenotypes and regulates thermogenesis and bone mass. Oxt may increases skeletal muscle tonicity and/or increases body temperature. In this review, the author compared the three most recent theories on the effects of Oxt on body composition.


Assuntos
Composição Corporal/efeitos dos fármacos , Ocitocina/farmacologia , Animais , Feminino , Humanos , Invertebrados/efeitos dos fármacos , Invertebrados/metabolismo , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/fisiologia , Gravidez , Termogênese/efeitos dos fármacos , Vasopressinas/metabolismo
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