Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 12.523
Filtrar
1.
Braz J Med Biol Res ; 52(9): e8551, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31482977

RESUMO

Fibroblasts are a highly heterogeneous population of cells, being found in a large number of different tissues. These cells produce the extracellular matrix, which is essential to preserve structural integrity of connective tissues. Fibroblasts are frequently engaged in migration and remodeling, exerting traction forces in the extracellular matrix, which is crucial for matrix deposition and wound healing. In addition, previous studies performed on primary myoblasts suggest that the E3 ligase MuRF2 might function as a cytoskeleton adaptor. Here, we hypothesized that MuRF2 also plays a functional role in skeletal muscle fibroblasts. We found that skeletal muscle fibroblasts express MuRF2 and its siRNA knock-down promoted decreased fibroblast migration, cell border accumulation of polymerized actin, and down-regulation of the phospho-Akt expression. Our results indicated that MuRF2 was necessary to maintain the actin cytoskeleton functionality in skeletal muscle fibroblasts via Akt activity and exerted an important role in extracellular matrix remodeling in the skeletal muscle tissue.


Assuntos
Diferenciação Celular/fisiologia , Proliferação de Células/fisiologia , Fibroblastos/fisiologia , Proteínas Musculares/fisiologia , Músculo Esquelético/fisiologia , Ubiquitina-Proteína Ligases/fisiologia , Animais , Western Blotting , Fibroblastos/metabolismo , Imunofluorescência , Camundongos , Proteínas Musculares/metabolismo , Músculo Esquelético/metabolismo , Ubiquitina-Proteína Ligases/metabolismo
2.
Gene ; 716: 144036, 2019 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-31381952

RESUMO

Nebulin is a 770 kDa protein that is localized along the thin filaments of skeletal muscles in vertebrates. It is also present in the striated muscles of Amphioxus, an invertebrate cephalochordate that is phylogenetically close to vertebrates. However, the nebulin of urochordate ascidians or its expression in invertebrate hearts has not been investigated. In this study, we investigated the structure and cardiac expression of the nebulin gene in Ciona intestinalis, a urochordate whose phylogeny lies between cephalochordates and vertebrates. As a result of the gene structure analysis, we found that the Ciona nebulin gene predicted to be 62 kb and consists of 143 exons. The nebulin was expected to consist of a unique N-terminal region, followed by 155 nebulin repeats, another unique region, a Ser-rich region and a C-terminal SH3 domain. Whole-mount in situ hybridization experiments showed that the Ciona nebulin gene was expressed in a variety of muscles, including hearts. However, Western blot analysis using antibody to Ciona nebulin did not detect the presence of full-length nebulin. Alternatively, RT-PCR experiments on samples of Ciona heart detected the expression of nebulette-like and nrap-like isoforms from the Ciona nebulin gene. These results indicate that, similarly to vertebrate hearts, Ciona hearts do not express nebulin, but rather nrap- and nebulette-like isoforms. These results also imply that the nebulin, nebulette and nrap genes in vertebrates were separated from an ancestral invertebrate nebulin gene during vertebrate evolution.


Assuntos
Ciona intestinalis/genética , Família Multigênica , Proteínas Musculares/genética , Miocárdio/metabolismo , Animais , Ciona intestinalis/metabolismo , Evolução Molecular , Éxons , Íntrons , Proteínas Musculares/química , Proteínas Musculares/metabolismo , Domínios Proteicos , RNA Mensageiro/metabolismo
3.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 35(3): 223-227, 2019 May 28.
Artigo em Chinês | MEDLINE | ID: mdl-31257803

RESUMO

OBJECTIVE: To investigate the therapeutic effects of massage on denervated skeletal muscle atrophy in rats and its mechanism. METHODS: Forty-eight male SD rats were randomly divided into model group (n=24) and massage group (n=24). Gastrocnemius muscle atrophy model was established by transecting the right tibial nerve of rat. On the second day after operation, the gastrocnemius muscle of the rats in the massage group was given manual intervention and the model group was not intervened. Six rats were sacrificed at the four time points of 0 d, 7 d, 14 d and 21 d. The gastrocnemius of the rats were obtained and measured the wet mass ratio after weighing. Cross-sectional area and diameter of the muscle fiber were measured after HE staining. The relative expressions of miR-23a, Akt, MuRF1 and MAFbx mRNA were tested with qPCR. RESULTS: Compared with 0 d, the wet weight ratio, cross-sectional area and diameter of gastrocnemius muscle showed a progressive decline in the model group and massage group. The wet weight ratio, cross-sectional area and diameter of gastrocnemius muscle in the massage group were higher than those in the model group on 7 d, 14 d and 21 d (P<0.05, P<0.01). Compared with 0 d, the expressions of MuRF1, MAFbx and Akt mRNA were increased first and then were decreased in the model group and massage group. The expression of MuRF1 mRNA in massage group was lower than that in model group on 7 d and 21 d (P<0.05, P<0.01). The expression of MAFbx mRNA in massage group was lower than that in model group on 7 d, 14 d and 21 d (P<0.01, P<0.05, P<0.01). The expression of Akt mRNA in massage group was higher than that in model group on 7 d, 14 d and 21 d (P<0.05, P<0.01). Compared with 0 d, the expression of miR-23a mRNA was increased in the model group and massage group on 21 d, and the expression of miR-23a mRNA in massage group was higher than that in model group (P< 0.05). CONCLUSION: Massage can delay the atrophy of denervated skeletal muscle. The mechanism may be related to up-regulation of the expression of miR-23a and Akt mRNA, down-regulation of the expressions of MuRF1 and MAFbx mRNA, inhibition of protein degradation rate, and reduction of skeletal muscle protein degradation.


Assuntos
Massagem , Músculo Esquelético/fisiopatologia , Atrofia Muscular/terapia , Animais , Masculino , MicroRNAs/metabolismo , Fibras Musculares Esqueléticas , Proteínas Musculares/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Ratos Sprague-Dawley , Proteínas Ligases SKP Culina F-Box/metabolismo , Proteínas com Motivo Tripartido/metabolismo , Ubiquitina-Proteína Ligases/metabolismo
4.
Life Sci ; 232: 116658, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31310758

RESUMO

AIMS: To investigate the cardioprotective effects of hypothermic (25 °C) reperfusion on ischemia/reperfusion injury and the role of transient potential channel M8 (TRPM8) in this process. MAIN METHODS: Western blot and real-time PCR were used to monitor the expression of TRPM8 in myocardium. Myocardial ischemia/reperfusion injury was induced by 30 min of global ischemia followed by 120 min of reperfusion in Langendorff-perfused hearts from Sprague-Dawley rats. The reperfusion was either normothermic (37 °C) or hypothermic (25 °C). Infarct size and left ventricular function were assessed, and lactate dehydrogenase (LDH), superoxide dismutase (SOD), and malondialdehyde (MDA) in the coronary effluent were measured spectrophotometrically, and cardiomyocyte apoptosis was detected by TUNEL assay. The expression of TRPM8, Bcl-2, Bax, cleaved capspase-3, RhoA, and ROCK2 was quantified. KEY FINDINGS: TRPM8 protein and mRNA were expressed in rat myocardium. Hypothermic reperfusion decreased the infarct size, LDH activity, MDA content, apoptosis, and expression of Bax, cleaved caspase-3, RhoA, and ROCK2 compared with normothermic reperfusion. These effects were associated with improved recovery of left ventricular contractility, and were reduced by BCTC, a TRPM8 antagonist. Ischemia/reperfusion injury and the increased expression of Bax, caspase-3, RhoA, and ROCK2 induced by normothermic reperfusion were reduced by Icilin, a TRPM8 agonist. SIGNIFICANCE: Hypothermic reperfusion at 25 °C has cardioprotective effects against ischemia/reperfusion injury via activation of TRPM8 to inhibit the oxidative stress-related RhoA/ROCK2 signal pathway.


Assuntos
Hipotermia/metabolismo , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Canais de Cátion TRPM/metabolismo , Animais , Apoptose , Hemodinâmica , L-Lactato Desidrogenase/metabolismo , Masculino , Proteínas Musculares/metabolismo , Traumatismo por Reperfusão Miocárdica/patologia , Miocárdio/enzimologia , Miocárdio/metabolismo , Ratos , Ratos Sprague-Dawley
5.
Food Chem ; 298: 125060, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31261004

RESUMO

Typical ketone flavours (with variations in chain length, position and number of keto group, branched chain) were selected to investigate the effect of molecule structure of ketones on their interactions with myofibrillar proteins (MPs). Results showed that 2,3-pentanedione quenched the fluorescence of MPs more effectively than 2-pentanone and 3-pentanone due to the number of keto group. There was no significant difference between 5-methyl-2-hexanone and 2-heptanone, which was attributed to their similar molecular size and polarity. The quenching effect of homologous ketone flavours increased with carbon chain growth due to the higher hydrophobic interaction. Dynamic quenching played a major role in the fluorescence quenching process of MPs by 2-pentanone, 3-pentanone, 5-methyl-2-hexanone, 2-heptanone and 2-octanone. The α-helix content decreased gradually with the increase of ketones concentration. Results of GC/MS were in accordance with the fluorescence quenching analysis generally, whereas 2,3-pentanedione and 2-nonanone exhibited some differences due to their higher steric hindrance effects.


Assuntos
Aromatizantes/química , Cetonas/química , Proteínas Musculares/química , Animais , Dicroísmo Circular , Aromatizantes/análise , Aromatizantes/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Cetonas/metabolismo , Proteínas Musculares/metabolismo , Ligação Proteica , Microextração em Fase Sólida , Espectrometria de Fluorescência , Suínos
6.
Life Sci ; 232: 116620, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31291594

RESUMO

AIMS: Cell-based biological pacemakers aim to overcome limitations and side effects of electronic pacemaker devices. We here developed and tested different approaches to achieve nodal-type differentiation using human adipose- and bone marrow-derived mesenchymal stem cells (haMSC, hbMSC). MAIN METHODS: haMSC and hbMSC were differentiated using customized protocols. Quantitative RT-PCR was applied for transcriptional pacemaker-gene profiling. Protein membrane expression was analyzed by immunocytochemistry. Pacemaker current (If) was studied in haMSC with and without lentiviral HCN4-transduction using patch clamp recordings. Functional characteristics were evaluated by co-culturing with neonatal rat ventricular myocytes (NRVM). KEY FINDINGS: Culture media-based differentiation for two weeks generated cells with abundant transcription of ion channel genes (Cav1.2, NCX1), transcription factors (TBX3, TBX18, SHOX2) and connexins (Cx31.9 and Cx45) characteristic for cardiac pacemaker tissue, but lack adequate HCN transcription. haMSC-derived cells revealed transcript levels, which were closer related to sinoatrial nodal cells than hbMSC-derived cells. To substitute for the lack of If, we performed lentiviral HCN4-transduction of haMSC resulting in stable If. Co-culturing with NRVM demonstrated that differentiated haMSC expressing HCN4 showed earlier onset of spontaneous contractions and higher beating regularity, synchrony and rate compared to co-cultures with non-HCN4-transduced haMSC or HCN4-transduced, non-differentiated haMSC. Confocal imaging indicated increased membrane expression of cardiac gap junctional proteins in differentiated haMSC. SIGNIFICANCE: By differentiation haMSC, rather than hbMSC attain properties favorable for cardiac pacemaking. In combination with lentiviral HCN4-transduction, a cellular phenotype was generated that sustainably controls and stabilizes rate in co-culture with NRVM.


Assuntos
Relógios Biológicos/fisiologia , Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização/metabolismo , Proteínas Musculares/metabolismo , Canais de Potássio/metabolismo , Tecido Adiposo/fisiologia , Animais , Células da Medula Óssea/fisiologia , Diferenciação Celular/fisiologia , Técnicas de Cocultura , Humanos , Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização/fisiologia , Células-Tronco Mesenquimais/metabolismo , Células Musculares/metabolismo , Proteínas Musculares/fisiologia , Miócitos Cardíacos/metabolismo , Técnicas de Patch-Clamp , Canais de Potássio/fisiologia , Ratos , Nó Sinoatrial
7.
Anim Sci J ; 90(8): 1060-1069, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31218792

RESUMO

The objective of this study was to determine the effect of two different freezing rate then thaw-aging regimens on the quality attributes of lamb loins. The loins were randomly allocated to one of five different freezing/thawing/aging regimes: fast-(FF1A0) and slow-(SF1A0) frozen only; fast-(FF1A2) and slow-(SF1A2) frozen then thaw-aged for 14 days; aged for 14 days never frozen (A2). FF1A2 samples had a significantly higher water-holding capacity compared to the slow frozen regardless of further aging periods. FF1A2 samples had lower (p < 0.05) shear force values than A2 and higher (p < 0.05) water-holding capacity compared to the SF1A2. Fast freezing resulted in more intracellular cryo-damage, whereas slow freezing resulted in extracellular cryo-damage. FF1A0 and SF1A0 samples had lower (p < 0.05) myofibrillar proteins degradation. This study demonstrated that fast freezing then thaw-aging can result in an improved water-holding capacity and tenderness through the minimization of extracellular ice crystal formation, reduction in purge and drip losses, and improved proteolysis in thawed lamb.


Assuntos
Conservação de Alimentos/métodos , Qualidade dos Alimentos , Congelamento , Carne , Animais , Congelamento/efeitos adversos , Carne/análise , Proteínas Musculares/metabolismo , Músculo Esquelético/química , Músculo Esquelético/patologia , Proteólise , Resistência ao Cisalhamento , Ovinos , Fatores de Tempo , Água/análise
8.
Food Chem ; 297: 125035, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31253330

RESUMO

In this study, an electrochemical system was established to detect the branched-chain amino acid aminotransferase (BCAT) activity in lactic acid bacteria (LAB). A nanocomposite of chitosan (CS) with multi-walled carbon nanotubes (MWCNTs) was synthesized, and the composite solution were uniformly spread over the glassy carbon electrode (GCE) surface by drop-casting to fabricate an electrochemical biosensor. The composite was characterized by scanning electron microscopy (SEM) and cyclic voltammetry (TEM). Results indicated that the MWCNTs-CS/GCE electrode exhibited higher stability and sensitivity, compared with the GCE electrode. The linear response for nicotinamide adenine dinucleotide (NADH) was 1.0-9.0 µM and the response limit was 0.12 µM. The system effectively and sensitively detected the BCAT activity by NADH concentration in the LAB culture, comparing with the optical method. The culture condition of LAB was optimized by using this system, evidencing that established method was available to detect the BCAT activity of LAB.


Assuntos
Proteínas de Bactérias/metabolismo , Técnicas Eletroquímicas/métodos , Lactobacillales/enzimologia , Transaminases/metabolismo , Técnicas Biossensoriais/métodos , Quitosana/química , Eletrodos , Proteínas Musculares/metabolismo , NAD/química , NAD/metabolismo , Nanotubos de Carbono/química
9.
Food Chem ; 293: 529-536, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31151644

RESUMO

The effect of glucose oxidase (GOx) catalytic oxidation on the efficacy of gallic acid (GA) to modify the chemical structure and gelling behavior of myofibrillar protein (MP) was investigated. In contrast to non-oxidized MP samples where GA induced very little changes, GA (0, 6, 30, and 60 µmol/g MP) under GOx treatment promoted sulfhydryl and amine loss (up to 58% and 49%, respectively). The attenuation of intrinsic tryptophan fluorescence in the GA/GOx-treated MP corroborated the finding. The gelling capacity of MP, corresponding to disulfide and non-disulfide bond formation in protein aggregates, was markedly enhanced by 60 µmol GA under GOx, up to 86% in gel storage modulus G' and 53% in gel strength. The GOx-aided GA modification of MP could be a potential ingredient strategy in meat processing to promote textural attributes of cooked products.


Assuntos
Ácido Gálico/química , Géis/química , Glucose Oxidase/metabolismo , Proteínas Musculares/química , Aminas/química , Aminas/metabolismo , Animais , Ácido Gálico/metabolismo , Carne/análise , Microscopia Eletrônica de Varredura , Proteínas Musculares/metabolismo , Oxirredução , Reologia , Compostos de Sulfidrila/química , Compostos de Sulfidrila/metabolismo
10.
Mol Med Rep ; 19(6): 4955-4963, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31059031

RESUMO

In most cases, exogenous oestradiol benzoate (EB) inhibits spermatogenesis, however, the mechanism underlying this process has not been fully elucidated. The present study investigated the effect of EB on redox equilibrium and glycometabolism in mouse testes. Male Kunming mice were divided into 3 groups and injected with 0, 5 and 10 mg/kg EB, respectively. Histological analysis revealed no sperm and far fewer spermatogenic cells in the testes of EB­treated mice. Additionally, transmission electron microscopy revealed that mitochondria in Sertoli cells were transformed to vacuoles with irregular cristae in the EB­treated group. EB also significantly decreased the activities and mRNA expression of catalase, superoxide dismutase, and glutathione peroxidase and increased the activity of nitric oxide synthase and nitric oxide concentration in the testes compared with the control. These results indicated that oxidative damage was caused by EB treatment. With regard to glycometabolism, ATP content and activities of hexokinase and pyruvate kinase were significantly reduced in the EB­treated group. Although glucose and pyruvate concentrations were significantly increased by EB treatment, levels of lactate, the main energy source of spermatogenic cells, were unchanged. Monocarboxylate transporter 2 (MCT2) and MCT4, which are responsible for lactate transportation, were downregulated by EB. In conclusion, the results of the present study indicated that azoospermia induced by EB in male mice was associated with oxidative damage and the disorder of testicular metabolic cooperation.


Assuntos
Azoospermia/patologia , Estradiol/análogos & derivados , Metaboloma/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Testículo/efeitos dos fármacos , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Azoospermia/induzido quimicamente , Azoospermia/veterinária , Cromatografia Líquida de Alta Pressão , Regulação para Baixo/efeitos dos fármacos , Estradiol/farmacologia , Transportador de Glucose Tipo 3/genética , Transportador de Glucose Tipo 3/metabolismo , Hexoquinase/genética , Hexoquinase/metabolismo , Masculino , Camundongos , Microscopia Eletrônica , Transportadores de Ácidos Monocarboxílicos/genética , Transportadores de Ácidos Monocarboxílicos/metabolismo , Proteínas Musculares/genética , Proteínas Musculares/metabolismo , Fosforilação/efeitos dos fármacos , Células de Sertoli/ultraestrutura , Espermatogênese/efeitos dos fármacos , Superóxido Dismutase/metabolismo , Testículo/metabolismo , Testículo/ultraestrutura
11.
Oxid Med Cell Longev ; 2019: 1724194, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31049126

RESUMO

Cardiovascular diseases (CVD) constitute one of the most prevalent health problems worldwide, being strongly associated with metabolic syndrome (MS). Oxidative stress (OS) is present in both CVD and MS. Infusions of Hibiscus sabdariffa Linnaeus (HSL) have antioxidant properties and could therefore decrease the presence of OS in these diseases. The aim of this study was to evaluate myocardial protection during ischemia/reperfusion due to the antioxidant effect of HSL infusion (3%) on a MS rat model induced by the administration of 30% sucrose in drinking water. We determined in control, MS, and MS + HSL rat hearts (n = 6 per group) cardiac mechanical performance (CMP), coronary vascular resistance (CVR), and activities of manganese and copper/zinc superoxide dismutases (Mn and Cu/Zn-SOD), peroxidases, glutathione peroxidase (GPx), catalase (CAT), glutathione s-transferase (GST), glutathione reductase (GR), and glutathione (GSH). We also determined lipoperoxidation (LPO), total antioxidant capacity (TAC), and the nitrate/nitrite ratio (NO3 -/NO2 -). The treatment with the HSL infusion restored the CMP (p = 0.01) and CVR (p = 0.04) and increased the Mn- (p = 0.02), Cu/Zn-SOD (p = 0.05), peroxidases (p = 0.04), GST (p = 0.02) activity, GHS (p = 0.02), TAC (p = 0.04), and NO3 -/NO2 - (p = 0.01) and decreased the LPO (p = 0.02) in the heart of MS rats undergoing ischemia/reperfusion. The results suggest that the treatment with an infusion from HSL calices protects the cardiac function from damage by ischemia and reperfusion through the antioxidant activities of the substances it possesses. It favors antioxidant enzymatic activities and nonenzymatic antioxidant capacity.


Assuntos
Antioxidantes/farmacologia , Cardiotônicos/farmacologia , Hibiscus/química , Síndrome Metabólica/tratamento farmacológico , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Miocárdio/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Animais , Antioxidantes/química , Cardiotônicos/química , Masculino , Síndrome Metabólica/metabolismo , Síndrome Metabólica/patologia , Proteínas Musculares/metabolismo , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/patologia , Miocárdio/patologia , Ratos
12.
J Food Sci ; 84(5): 1054-1059, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31042817

RESUMO

This study was designed to determine the effects of µ/m-calpain on the degradation of cytoskeletal proteins in pectoralis major. Four chickens were slaughtered and the breasts were removed and stored for 12 hr at 4 °C. Each sample was divided into three groups and respectively immersed in control reagent, calpain inhibitor, and caspase inhibitor at 4 °C. The samples were used to evaluate troponin-T and desmin degradation, calpain activity, and myofibril ultrastructure at 12 hr, day 1, day 3, and day 7. Casein zymography revealed that µ-calpain could not be detected in all samples after 12 hr postmortem. The calpain inhibitor inhibited µ/m-calpain activity and reduced troponin-T and desmin degradation during 7 day postmortem. The caspase inhibitor inhibited µ/m-calpain activity and, troponin-T and desmin degradation before day 3 postmortem. The findings suggest that, µ/m-calpain had an effect on cytoskeletal protein degradation after 12 hr postmortem.


Assuntos
Calpaína , Carne/análise , Proteínas Musculares , Animais , Calpaína/antagonistas & inibidores , Calpaína/metabolismo , Galinhas , Proteínas Musculares/química , Proteínas Musculares/metabolismo , Músculo Esquelético/química , Músculo Esquelético/metabolismo
13.
Anim Sci J ; 90(8): 1018-1025, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31132809

RESUMO

Dietary fish oil intake improves muscle atrophy in several atrophy models however the effect on denervation-induced muscle atrophy is not clear. Thus, the aim of this study was to investigate the effects of dietary fish oil intake on muscle atrophy and the expression of muscle atrophy markers induced by sciatic nerve denervation in mice. We performed histological and quantitative mRNA expression analysis of muscle atrophy markers in mice fed with fish oil with sciatic nerve denervation. Histological analysis indicated that dietary fish oil intake slightly prevented the decrease of muscle fiber diameter induced by denervation treatment. In addition, dietary fish oil intake suppressed the MuRF1 (tripartite motif-containing 63) expression up-regulated by denervation treatment, and this was due to decreased tumor necrosis factor-alpha (TNF-α) production in skeletal muscle. We concluded that dietary fish oil intake suppressed MuRF1 expression by decreasing TNF-α production during muscle atrophy induced by sciatic nerve denervation in mice.


Assuntos
Denervação/efeitos adversos , Gorduras Insaturadas na Dieta/farmacologia , Óleos de Peixe/farmacologia , Expressão Gênica/efeitos dos fármacos , Proteínas Musculares/metabolismo , Atrofia Muscular/etiologia , Nervo Isquiático , Proteínas com Motivo Tripartido/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Animais , Masculino , Camundongos Endogâmicos C57BL , Fibras Musculares Esqueléticas/patologia , Proteínas Musculares/genética , Músculo Esquelético/metabolismo , Atrofia Muscular/prevenção & controle , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas com Motivo Tripartido/genética , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo , Ubiquitina-Proteína Ligases/genética , Regulação para Cima/efeitos dos fármacos
14.
Mol Cell Biochem ; 458(1-2): 79-87, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30993497

RESUMO

Although exercise affects the function and structure of skeletal muscle, our knowledge regarding the biomedical alterations induced by different intensities of exercise is incomplete. Here we report on the changes in biomarker levels and myofiber constitution in the rat soleus muscle induced by exercise intensity. Male adult rats at 7 weeks of age were divided into 3 groups by exercise intensity, which was set based on the accumulated lactate levels in the blood using a treadmill: stationary control (0 m/min), aerobic exercise (15 m/min), and anaerobic exercise (25 m/min). The rats underwent 30 min/day treadmill training at different exercise intensities for 14 days. Immediately after the last training session, the soleus muscle was dissected out in order to measure the muscle biomarker levels and evaluate the changes in the myofibers. The mRNA expression of citrate synthase, glucose-6-phosphate dehydrogenase, and Myo D increased with aerobic exercise, while the mRNA expression of myosin heavy-chain I and Myo D increased in anaerobic exercise. These results suggest that muscle biomarkers can be used as parameters for the muscle adaptation process in aerobic/anaerobic exercise. Interestingly, by 14 days after the anaerobic exercise, the number of type II (fast-twitch) myofibers had decreased by about 20%. Furthermore, many macrophages and regenerated fibers were observed in addition to the injured fibers 14 days after the anaerobic exercise. Constitutional changes in myofibers due to damage incurred during anaerobic exercise are necessary for at least about 2 weeks. These results indicate that the changes in the biomarker levels and myofiber constitution by exercise intensity are extremely important for understanding the metabolic adaptations of skeletal muscle during physical exercise.


Assuntos
Fibras Musculares de Contração Rápida/metabolismo , Fibras Musculares de Contração Lenta/metabolismo , Proteínas Musculares/metabolismo , Condicionamento Físico Animal , Animais , Biomarcadores/metabolismo , Masculino , Ratos , Ratos Wistar , Fatores de Tempo
15.
J Sci Food Agric ; 99(11): 5028-5034, 2019 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-30989657

RESUMO

BACKGROUND: The influence of heat-induced structural modifications of grass carp myofibrillar protein (MP) on its ability to bind to selected aldehydes (hexanal, heptanal, octanal and nonanal) was investigated. The interactions of MP and flavor compounds were investigated using HS-GC-MS, intrinsic fluorescence spectra, Raman spectra, SDS-PAGE, turbidity, total sulfhydryl content and surface hydrophobicity. RESULTS: The ability to bind to aldehydes was strongly influenced by changes in the structure and surface of proteins during the heating process (0-30 min). During the first 0-10 min of heating, the flavor-binding ability increased, which is likely attributable to increased surface hydrophobicity and total sulfhydryl content, and to the unfolding of secondary structures of MP by exposure to reactive amino acids, sulfhydryl groups and hydrophobic bonding sites. Nevertheless, lengthy heating (>10 min) caused protein refolding and accelerated aggregation of protein, thus reducing hydrophobic interactions and weakening the resultant capacity of MP to bind to flavor compounds. CONCLUSION: The results suggested that hydrophobic interactions were enhanced upon short-term heating, whereas long-term heating weakend them. The results provide information concerning improvement of the flavor profile of freshwater fish surimi products. © 2019 Society of Chemical Industry.


Assuntos
Aldeídos/metabolismo , Cyprinidae , Temperatura Alta , Proteínas Musculares/metabolismo , Miofibrilas/química , Animais , Eletroforese em Gel de Poliacrilamida , Cromatografia Gasosa-Espectrometria de Massas , Interações Hidrofóbicas e Hidrofílicas , Estrutura Molecular , Proteínas Musculares/química , Ligação Proteica , Espectrometria de Fluorescência , Análise Espectral Raman , Compostos de Sulfidrila/análise , Paladar
16.
Biomed Pharmacother ; 112: 108681, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30970510

RESUMO

Acute kidney injury (AKI) is a significant medical problem worldwide. Ischemia-reperfusion (I/R) injury of the kidney is a major cause of AKI. However, the pathogenesis that contributes to renal I/R injury is still unclear. Apoptosis repressor with caspase recruitment domain (ARC) is abundantly expressed in various tissues, and has been reported to play a strong protective role during pathological processes. Our results indicated that ARC expression was decreased in the reperfused kidneys. ARC deficiency markedly accelerated renal dysfunction, promoted reperfusion-regulated tubular epithelial cell apoptosis, and enhanced the vulnerability of kidney to I/R damage. Furthermore, in the kidney samples of mice underwent renal I/R injury, ARC knockout significantly accelerated the expression levels of inflammatory factors, including interleukin (IL)-1ß, IL-6, tumor necrosis factor a (TNF-α), monocyte chemoattractant protein-1 (MCP-1) and IL-2. In addition, renal I/R injury-induced apoptosis was further exacerbated in ARC-deficient mice through promoting the expression of cleaved Caspase-3 and poly (ADP-ribose) polymerase (PARP). From the molecular level, ARC deletion obviously accelerated mitochondrial injury, as evidenced by the further decreased adenosine triphosphate (ATP) levels and mitochondrial potential in hypoxia-reoxygenation (H/R)-treated cells. Moreover, ARC knockout exacerbated AKI through activating phosphorylated protein kinase B (AKT), mammalian target of Rapamycin (mTOR) and p53, whereas reducing phosphorylated glycogen synthase kinase 3ß (GSK3ß). Of note, blocking AKT/mTOR signaling markedly attenuated inflammation, mitochondrial damage and apoptosis stimulated by H/R in ARC knockdown cells. In summary, our results suggested that ARC played a pivotal role in the pathogenesis of AKI induced by renal I/R operation through regulating AKT/mTOR signaling.


Assuntos
Lesão Renal Aguda/metabolismo , Proteínas Reguladoras de Apoptose/metabolismo , Apoptose , Rim/metabolismo , Proteínas Musculares/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Traumatismo por Reperfusão/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Lesão Renal Aguda/imunologia , Lesão Renal Aguda/patologia , Animais , Apoptose/imunologia , Proteínas Reguladoras de Apoptose/genética , Linhagem Celular , Sobrevivência Celular , Citocinas/metabolismo , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Humanos , Inflamação , Rim/imunologia , Rim/patologia , Túbulos Renais Proximais/citologia , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Musculares/genética , Traumatismo por Reperfusão/imunologia , Traumatismo por Reperfusão/patologia , Transdução de Sinais
17.
Skelet Muscle ; 9(1): 9, 2019 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-30992050

RESUMO

BACKGROUND: Critical illness myopathy (CIM) is associated with severe skeletal muscle wasting and impaired function in intensive care unit (ICU) patients. The mechanisms underlying CIM remain incompletely understood. To elucidate the biological activities occurring at the transcriptional level in the skeletal muscle of ICU patients with CIM, the gene expression profiles, potential upstream regulators, and enrichment pathways were characterized using RNA sequencing (RNA-seq). We also compared the skeletal muscle gene signatures in ICU patients with CIM and genes perturbed by mechanical loading in one leg of the ICU patients, with an aim of reducing the loss of muscle function. METHODS: RNA-seq was used to assess gene expression changes in tibialis anterior skeletal muscle samples from seven critically ill, immobilized, and mechanically ventilated ICU patients with CIM and matched control subjects. We also examined skeletal muscle gene expression for both legs of six ICU patients with CIM, where one leg was mechanically loaded for 10 h/day for an average of 9 days. RESULTS: In total, 6257 of 17,221 detected genes were differentially expressed (84% upregulated; p < 0.05 and fold change ≥ 1.5) in skeletal muscle from ICU patients with CIM when compared to control subjects. The differentially expressed genes were highly associated with gene changes identified in patients with myopathy, sepsis, long-term inactivity, polymyositis, tumor, and repeat exercise resistance. Upstream regulator analysis revealed that the CIM signature could be a result of the activation of MYOD1, p38 MAPK, or treatment with dexamethasone. Passive mechanical loading only reversed expression of 0.74% of the affected genes (46 of 6257 genes). CONCLUSIONS: RNA-seq analysis revealed that the marked muscle atrophy and weakness observed in ICU patients with CIM were associated with the altered expression of genes involved in muscle contraction, newly identified E3 ligases, autophagy and calpain systems, apoptosis, and chaperone expression. In addition, MYOD1, p38 MAPK, and dexamethasone were identified as potential upstream regulators of skeletal muscle gene expression in ICU patients with CIM. Mechanical loading only marginally affected the skeletal muscle transcriptome profiling of ICU patients diagnosed with CIM.


Assuntos
Apoptose , Autofagia , Chaperonas Moleculares/metabolismo , Contração Muscular , Músculo Esquelético/metabolismo , Doenças Musculares/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Estado Terminal , Feminino , Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Chaperonas Moleculares/genética , Proteínas Musculares/genética , Proteínas Musculares/metabolismo , Debilidade Muscular/genética , Debilidade Muscular/metabolismo , Atrofia Muscular/etiologia , Atrofia Muscular/metabolismo , Doenças Musculares/etiologia , Análise de Sequência de RNA , Transcriptoma , Ubiquitina-Proteína Ligases/genética
18.
Dokl Biochem Biophys ; 484(1): 9-12, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31012002

RESUMO

An effective bacterial system for the production of ß-toxin Ts1, the main component of the Brazilian scorpion Tityus serrulatus venom, was developed. Recombinant toxin and its 15N-labeled analogue were obtained via direct expression of synthetic gene in Escherichia coli with subsequent folding from the inclusion bodies. According to NMR spectroscopy data, the recombinant toxin is structured in an aqueous solution and contains a significant fraction of ß-structure. The formation of a stable disulfide-bond isomer of Ts1, having a disordered structure, has also been observed during folding. Recombinant Ts1 blocks Na+ current through NaV1.5 channels without affecting the processes of activation and inactivation. At the same time, the effect upon NaV1.4 channels is associated with a shift of the activation curve towards more negative membrane potentials.


Assuntos
Venenos de Escorpião , Bloqueadores dos Canais de Sódio , Animais , Humanos , Proteínas Musculares/metabolismo , Canal de Sódio Disparado por Voltagem NAV1.4/metabolismo , Canal de Sódio Disparado por Voltagem NAV1.5/metabolismo , Ressonância Magnética Nuclear Biomolecular , Estrutura Secundária de Proteína , Ratos , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/farmacologia , Venenos de Escorpião/biossíntese , Venenos de Escorpião/química , Venenos de Escorpião/isolamento & purificação , Venenos de Escorpião/farmacologia , Bloqueadores dos Canais de Sódio/química , Bloqueadores dos Canais de Sódio/isolamento & purificação , Bloqueadores dos Canais de Sódio/farmacologia , Canais de Sódio/metabolismo , Relação Estrutura-Atividade , Xenopus laevis
19.
Nat Commun ; 10(1): 1791, 2019 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-30996251

RESUMO

Apoptotic death of cells damaged by genotoxic stress requires regulatory input from surrounding tissues. The C. elegans scaffold protein KRI-1, ortholog of mammalian KRIT1/CCM1, permits DNA damage-induced apoptosis of cells in the germline by an unknown cell non-autonomous mechanism. We reveal that KRI-1 exists in a complex with CCM-2 in the intestine to negatively regulate the ERK-5/MAPK pathway. This allows the KLF-3 transcription factor to facilitate expression of the SLC39 zinc transporter gene zipt-2.3, which functions to sequester zinc in the intestine. Ablation of KRI-1 results in reduced zinc sequestration in the intestine, inhibition of IR-induced MPK-1/ERK1 activation, and apoptosis in the germline. Zinc localization is also perturbed in the vasculature of krit1-/- zebrafish, and SLC39 zinc transporters are mis-expressed in Cerebral Cavernous Malformations (CCM) patient tissues. This study provides new insights into the regulation of apoptosis by cross-tissue communication, and suggests a link between zinc localization and CCM disease.


Assuntos
Proteínas Reguladoras de Apoptose/metabolismo , Apoptose/fisiologia , Proteínas de Caenorhabditis elegans/metabolismo , Proteínas de Transporte de Cátions/metabolismo , Hemangioma Cavernoso do Sistema Nervoso Central/patologia , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Zinco/metabolismo , Animais , Animais Geneticamente Modificados , Apoptose/efeitos da radiação , Proteínas Reguladoras de Apoptose/genética , Encéfalo/patologia , Encéfalo/cirurgia , Caenorhabditis elegans/fisiologia , Caenorhabditis elegans/efeitos da radiação , Proteínas de Caenorhabditis elegans/genética , Modelos Animais de Doenças , Perfilação da Expressão Gênica , Hemangioma Cavernoso do Sistema Nervoso Central/genética , Hemangioma Cavernoso do Sistema Nervoso Central/cirurgia , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteína KRIT1/genética , Proteína KRIT1/metabolismo , Fatores de Transcrição Kruppel-Like/metabolismo , Sistema de Sinalização das MAP Quinases/fisiologia , Camundongos , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 7 Ativada por Mitógeno/metabolismo , Proteínas Musculares/genética , Proteínas Musculares/metabolismo , Mutagênese , Mutação , Fosforilação/fisiologia , Alinhamento de Sequência , Peixe-Zebra , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
20.
Food Chem ; 291: 245-252, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31006466

RESUMO

Transglutaminase is an effective enzyme that catalyzes the crosslinking of various meats, improves meat product quality, and is widely used in the meat industry. In this study, microbial transglutaminase (MTG) was expressed successfully in Pichia pastoris strain GS115, and the enzyme activity was approximately 0.70 U/ml. The recombinant MTG expressed in P. pastoris was used in the investigation of restructured pork and crosslinking of soy protein isolate (SPI) and chicken myofibrillar protein (MP). Results showed that the hardness, chewiness, and F1 of the restructured pork increased, and the adhesiveness decreased after MTG treatment, However, high temperature had greater effect on the texture of restructured pork after MTG treatment than that of the control. MTG can crosslink SPI component acidic subunits, subunits of ß-conglycinin and MP component myosin heavy chain, and actin. MTG, as a food additive, can be successfully heterologously expressed, and the recombinant MTG has potential application in restructured meat products.


Assuntos
Produtos da Carne/análise , Pichia/metabolismo , Proteínas Recombinantes/metabolismo , Transglutaminases/metabolismo , Animais , Galinhas/metabolismo , Proteínas Musculares/metabolismo , Proteínas Recombinantes/isolamento & purificação , Proteínas de Soja/metabolismo , Suínos , Transglutaminases/genética
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA