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Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by impaired social interactions, communication deficits and repetitive behaviors. A study of autistic human subjects has identified RFWD2 as a susceptibility gene for autism, and autistic patients have 3 copies of the RFWD2 gene. The role of RFWD2 as an E3 ligase in neuronal functions, and its contribution to the pathophysiology of ASD, remain unknown. We generated RFWD2 knockin mice to model the human autistic condition of high gene dosage of RFWD2. We found that heterozygous knockin (Rfwd2+/-) male mice exhibited the core symptoms of autism. Rfwd2+/- male mice showed deficits in social interaction and communication, increased repetitive and anxiety-like behavior, and spatial memory deficits, whereas Rfwd2+/- female mice showed subtle deficits in social communication and spatial memory but were normal in anxiety-like, repetitive, and social behaviors. These autistic-like behaviors in males were accompanied by a reduction in dendritic spine density and abnormal synaptic function on layer II/III pyramidal neurons in the prelimbic area of the medial prefrontal cortex (mPFC), as well as decreased expression of synaptic proteins. Impaired social behaviors in Rfwd2+/- male mice were rescued by the expression of ETV5, one of the major substrates of RFWD2, in the mPFC. These findings indicate an important role of RFWD2 in the pathogenesis of autism.
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Mechanosensitive ion channels are widely distributed in the heart, lung, bladder and other tissues, and plays an important role in exercise-induced cardiovascular function promotion. By reviewing the PubMed databases, the results were summarized using the terms "Exercise/Sport", "Piezo1", "Transient receptor potential (TRP)" and "Cardiovascular" as the keywords, 124-related papers screened were sorted and reviewed. The results showed that: (1) Piezo1 and TRP channels play an important role in regulating blood pressure and the development of cardiovascular diseases such as atherosclerosis, myocardial infarction, and cardiac fibrosis; (2) Exercise promotes cardiac health, inhibits the development of pathological heart to heart failure, regulating the changes in the characterization of Piezo1 and TRP channels; (3) Piezo1 activates downstream signaling pathways with very broad pathways, such as AKT/eNOS, NF-κB, p38MAPK and HIPPO-YAP signaling pathways. Piezo1 and Irisin regulate nuclear localization of YAP and are hypothesized to act synergistically to regulate tissue mechanical properties of the cardiovascular system and (4) The cardioprotective effects of exercise through the TRP family are mostly accomplished through Ca2+ and involve many signaling pathways. TRP channels exert their important cardioprotective effects by reducing the TRPC3-Nox2 complex and mediating Irisin-induced Ca2+ influx through TRPV4. It is proposed that exercise stimulates the mechanosensitive cation channel Piezo1 and TRP channels, which exerts cardioprotective effects. The activation of Piezo1 and TRP channels and their downstream targets to exert cardioprotective function by exercise may provide a theoretical basis for the prevention of cardiovascular diseases and the rehabilitation of clinical patients.
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Reclaimed water is an effective method for addressing water pollution and shortages. However, its use may contribute to the collapse of receiving water (algal blooms and eutrophication) owing to its unique characteristics. A three-year biomanipulation project was conducted in Beijing to investigate the structural changes, stability, and potential risks to aquatic ecosystems associated with the reuse of reclaimed water in rivers. During the biomanipulation, the proportion of Cyanophyta in the community structure of phytoplankton density in river supplied with reclaimed water decreased, and the community composition shifted from Cyanophyta and Chlorophyta to Chlorophyta and Bacillariophyta. The biomanipulation project increased the number of zoobenthos and fish species and significantly increased fish density. Despite the significant difference in aquatic organisms community structure, diversity index and community stability of aquatic organisms remained stable during the biomanipulation. Our study provides a strategy for minimizing the hazards of reclaimed water through biomanipulation by reconstructing the community structure of reclaimed water, thereby making it safe for large-scale reuse in rivers.
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Cianobactérias , Rios , Animais , Água , Ecossistema , Fitoplâncton , China , Eutrofização , Qualidade da ÁguaRESUMO
Myocardial infarction (MI) causes peripheral organ injury, in addition to cardiac dysfunction, including in the liver, which is known as cardiac hepatopathy. Aerobic exercise (AE) can effectively improve liver injury, although the mechanism and targets are currently not well established. Irisin, mainly produced by cleavage of the fibronectin type III domain-containing protein 5 (FNDC5), is a responsible for the beneficial effects of exercise training. In this study, we detected the effect of AE on MI-induced liver injury and explored the role of irisin alongside the benefits of AE. Wildtype and Fndc5 knockout mice were used to establish an MI model and subjected to AE intervention. Primary mouse hepatocytes were treated with lipopolysaccharide (LPS), rhirisin, and a phosphoinositide 3-kinase (PI3K) inhibitor. The results showed that AE significantly promoted M2 polarization of macrophages and improved MI-induced inflammation, upregulated endogenous irisin protein expression and activated the PI3K/ protein kinase B (Akt) signaling pathway in the liver of MI mice, while knockout of Fndc5 attenuated the beneficial effects of AE. Exogenous rhirisin significantly inhibited the LPS-induced inflammatory response, which was attenuated by the PI3K inhibitor. These results suggest that AE could effectively activate the FNDC5/irisin-PI3K/Akt signaling pathway, promote the polarization of M2 macrophages, and inhibit the inflammatory response of the liver after MI.
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Fibronectinas , Fígado , Infarto do Miocárdio , Condicionamento Físico Animal , Animais , Camundongos , Fibronectinas/metabolismo , Lipopolissacarídeos , Fígado/metabolismo , Fígado/patologia , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Fatores de TranscriçãoRESUMO
Municipal wastewater treatment often lacks carbon source, while carbon-rich organics in food waste are deficiently utilized. In this study, the food waste fermentation liquid (FWFL) was step-fed into a bench-scale step-feed three-stage anoxic/aerobic system (SFTS-A/O), to investigate its performance in nutrients removal and the response of microbial community as a supplementary carbon source. The results showed that the total nitrogen (TN) removal rate increased by 21.8-109.3% after step-feeding FWFL. However, the biomass of the SFTS-A/O system was increased by 14.6% and 11.9% in the two phases of the experiment, respectively. Proteobacteria was found to be the dominant functional phyla induced by FWFL, and the increase of its abundance attributed to the enrichment of denitrifying bacteria and carbohydrate-metabolizing bacteria was responsible for the biomass increase. Azospira belonged to Proteobacteria phylum was the dominant denitrifying genera when step-fed with FWFL, its abundance was increased from 2.7% in series 1 (S1) to 18.6% in series 2 (S2) and became the keystone species in the microbial networks. Metagenomics analysis revealed that step-feeding FWFL enhanced the abundance of denitrification and carbohydrates-metabolism genes, which were encode mainly by Proteobacteria. This study constitutes a key step towards the application of FWFL as a supplementary carbon source for low C/N municipal wastewater treatment.
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Microbiota , Eliminação de Resíduos , Febre Grave com Síndrome de Trombocitopenia , Humanos , Águas Residuárias , Fermentação , Alimentos , Eliminação de Resíduos Líquidos/métodos , Carbono , Esgotos , Reatores Biológicos , Nitrogênio , DesnitrificaçãoRESUMO
Guanine nucleotide exchange factor Kalirin-7 (Kal-7) is a key factor in synaptic plasticity and plays an important regulatory role in the brain. Abnormal synaptic function leads to the weakening of cognitive functions such as learning and memory, accompanied by abnormal expression of Kal-7, which in turn induces a variety of neurodegenerative diseases. Exercise can upregulate the expression of Kal-7 in related brain regions to alleviate neurodegenerative diseases. By reviewing the literature on Kal-7 and neurodegenerative diseases, as well as the research progress of exercise intervention, this paper summarizes the role and possible mechanism of Kal-7 in the improvement of neurodegenerative diseases by exercise and provides a new rationale for the basic and clinical research on the prevention and treatment of neurodegenerative diseases by exercise.
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Doenças Neurodegenerativas , Humanos , Doenças Neurodegenerativas/terapia , Fatores de Troca do Nucleotídeo Guanina/genética , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Terapia por ExercícioRESUMO
Myocardial infarction (MI)-induced heart failure (HF) is commonly accompanied with profound effects on skeletal muscle. With the process of MI-induced HF, perturbations in skeletal muscle contribute to muscle atrophy. Exercise is viewed as a feasible strategy to prevent muscle atrophy. The aims of this study were to investigate whether exercise could alleviate MI-induced skeletal muscle atrophy via insulin-like growth factor 1 (IGF-1) pathway in mice. Male C57/BL6 mice were used to establish the MI model and were divided into three groups: sedentary MI group (MI), MI with aerobic exercise group, and MI with resistance exercise group; sham-operated group was used as control. Exercise-trained animals were subjected to 4 wk of aerobic exercise (AE) or resistance exercise (RE). Cardiac function, muscle weight, myofiber size, levels of IGF-1 signaling and proteins related to myogenesis, protein synthesis, and degradation and apoptosis in gastrocnemius muscle were detected. H2O2-treated C2C12 cells were intervened with recombinant human IGF-1, IGF-1 receptor (IGF-1R) inhibitor NVP-AEW541, and PI3K inhibitor LY294002 to explore the mechanism. Exercises upregulated the IGF-1/IGF-1R-phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) signaling; increased the expressions of Pax7, myogenic regulatory factors (MRFs), and protein synthesis; and reduced protein degradation and cell apoptosis in MI mice. In vitro, IGF-1 upregulated the levels of Pax7, MRFs, mTOR, and P70S6K; reduced MuRF1 and MAFbx; and inhibited cell apoptosis via IGF-1R-PI3K/Akt pathway. AE and RE, safely and effectively, alleviate skeletal muscle atrophy by regulating the levels of myogenesis, protein degradation, and cell apoptosis in mice with MI via activating IGF-1/IGF-1R-PI3K/Akt signaling pathway.
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Fator de Crescimento Insulin-Like I/biossíntese , Atrofia Muscular/metabolismo , Infarto do Miocárdio/metabolismo , Condicionamento Físico Animal/fisiologia , Receptor IGF Tipo 1/biossíntese , Treinamento Resistido , Animais , Linhagem Celular , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Atrofia Muscular/diagnóstico por imagem , Atrofia Muscular/terapia , Infarto do Miocárdio/diagnóstico por imagem , Infarto do Miocárdio/terapia , Fosfatidilinositol 3-Quinase/biossíntese , Condicionamento Físico Animal/métodos , Proteínas Proto-Oncogênicas c-akt/biossíntese , Treinamento Resistido/métodos , Transdução de Sinais/fisiologiaRESUMO
Skeletal muscle mass and function tend to decline with increasing age. Insulin-like growth factor 1 (IGF-1) plays a key role in promoting skeletal muscle growth. Exercise improves skeletal muscle mass and function via the activation of IGF-1 signaling. The aim of this study was to investigate whether different types of exercise can promote muscle hypertrophy, exercise and metabolic capacities, and activate IGF-1 signaling during early aging in mice. We randomly assigned 12 month old male C57/BL6 mice into five groups: control, aerobic exercise, resistance exercise, whole-body vibration and electrical stimulation group. Gastrocnemius muscle mass, myofiber size, levels of IGF-1 signaling, oxidative stress, protein synthesis and degradation, and apoptosis were detected. C2C12 cells were used to explore the mechanism by which exercise exerts its effects. We confirmed that the four modes of exercise increased skeletal muscle mass, exercise capacity, indicators of metabolism and protein synthesis, and inhibited oxidative stress and apoptosis via activation of the IGF-1 pathway. The most effective intervention was resistance exercise. Whole-body vibration promoted muscle hypertrophy better than aerobic exercise. Furthermore, in the in vitro experiment, the importance of IGF-1/IGF-1R-PI3K/Akt signaling for maintaining skeletal muscle mass was confirmed. Aerobic exercise, resistance exercise, whole-body vibration and electrical stimulation increased skeletal muscle mass, exercise capacity, protein synthesis and metabolic enzyme activity, and inhibited protein degradation and apoptosis in mice undergoing early aging via activation of IGF-1 signaling. Of these, whole-body vibration has been shown to be significantly effective and is similar to conventional exercise in promoting muscle hypertrophy.
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Envelhecimento , Terapia por Exercício , Músculo Esquelético , Animais , Masculino , Camundongos , Envelhecimento/fisiologia , Hipertrofia , Fator de Crescimento Insulin-Like I/metabolismo , Músculo Esquelético/metabolismo , Músculo Esquelético/fisiologia , Fosfatidilinositol 3-Quinases/metabolismo , Terapia por Exercício/métodos , Resultado do Tratamento , Transdução de SinaisRESUMO
Cardiolipin is a mitochondrial signature phospholipid that plays a pivotal role in maintaining cardiac health. A loss of tetralinoleoyl cardiolipin (TLCL), the predominant cardiolipin species in the healthy mammalian heart, is implicated in the pathogenesis of coronary heart disease (CHD) through poorly defined mechanisms. Here, we identified acyl-coenzyme A:lysocardiolipin acyltransferase-1 (ALCAT1) as the missing link between hypoxia and CHD in an animal model of myocardial infarction (MI). ALCAT1 is an acyltransferase that promotes mitochondrial dysfunction in aging-related diseases by catalyzing pathological remodeling of cardiolipin. In support of a causative role of ALCAT1 in CHD, we showed that ALCAT1 expression was potently upregulated by MI, linking myocardial hypoxia to oxidative stress, TLCL depletion, and mitochondrial dysfunction. Accordingly, ablation of the ALCAT1 gene or pharmacological inhibition of the ALCAT1 enzyme by Dafaglitapin (Dafa), a potent and highly specific ALCAT1 inhibitor, not only restored TLCL levels but also mitochondrial respiration by attenuating signal transduction pathways mediated by hypoxia-inducible factor 1α (HIF-1α). Consequently, ablation or pharmacological inhibition of ALCAT1 by Dafa effectively mitigated CHD and its underlying pathogenesis, including dilated cardiomyopathy, left ventricle dysfunction, myocardial inflammation, fibrosis, and apoptosis. Together, the findings have provided the first proof-of-concept studies for targeting ALCAT1 as an effective treatment for CHD.
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Cardiolipinas , Doença da Artéria Coronariana , Animais , Cardiolipinas/metabolismo , Doença da Artéria Coronariana/metabolismo , Hipóxia/genética , Hipóxia/metabolismo , Mamíferos , Mitocôndrias/genética , Mitocôndrias/metabolismo , Estresse OxidativoRESUMO
Exercise training has been reported to alleviate cardiac fibrosis and ameliorate heart dysfunction after myocardial infarction (MI), but the molecular mechanism is still not fully clarified. Fibroblast growth factor 21 (FGF21) exerts a protective effect on the infarcted heart. This study investigates whether exercise training could increase FGF21 protein expression and regulate the transforming growth factor-ß1 (TGF-ß1)-Smad2/3-MMP2/9 signaling pathway to alleviate cardiac fibrosis following MI. Male wild type (WT) C57BL/6J mice and Fgf21 knockout (Fgf21 KO) mice were used to establish the MI model and subjected to five weeks of different types of exercise training. Both aerobic exercise training (AET) and resistance exercise training (RET) significantly alleviated cardiac dysfunction and fibrosis, up-regulated FGF21 protein expression, inhibited the activation of TGF-ß1-Smad2/3-MMP2/9 signaling pathway and collagen production, and meanwhile, enhanced antioxidant capacity and reduced cell apoptosis in the infarcted heart. In contrast, knockout of Fgf21 weakened the cardioprotective effects of AET after MI. In vitro, cardiac fibroblasts (CFs) were isolated from neonatal mice hearts and treated with H2O2 (100 µM, 6 h). Recombinant human FGF21 (rhFGF21, 100 ng/mL, 15 h) and/or 5-Aminoimidazole-4-carboxamide ribonucleotide (AICAR, 1 mM, 15 h) inhibited H2O2-induced activation of the TGF-ß1-Smad2/3-MMP2/9 signaling pathway, promoted CFs apoptosis and reduced collagen production. In conclusion, exercise training increases FGF21 protein expression, inactivates the TGF-ß1-Smad2/3-MMP2/9 signaling pathway, alleviates cardiac fibrosis, oxidative stress, and cell apoptosis, and finally improves cardiac function in mice with MI. FGF21 plays an important role in the anti-fibrosis effect of exercise training.
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Terapia por Exercício/métodos , Fatores de Crescimento de Fibroblastos/metabolismo , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/terapia , Miocárdio/patologia , Transdução de Sinais/genética , Proteína Smad2/metabolismo , Proteína Smad3/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Animais , Apoptose/genética , Células Cultivadas , Modelos Animais de Doenças , Fatores de Crescimento de Fibroblastos/genética , Fibroblastos/metabolismo , Fibrose , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Recombinantes/metabolismoRESUMO
Insulin-like growth factor-1 (IGF-1) is a peptide with a similar molecular structure to insulin. IGF-1 plays a key role in tissue growth and development, as well as cell metabolism, proliferation, differentiation and apoptosis. Liver is the main source of IGF-1, with the production of IGF-1 up to 75% of the total in the whole body, while the remaining 25% are secreted by skeletal muscles, heart, kidney, spleen and other organs. Target organs of IGF-1 include heart, blood vessels, liver, bone and skeletal muscles. It has been well documented that IGF-1 plays an important role in the prevention and treatment of metabolic diseases. Different types of exercise have different effects on IGF-1 expression with organ differences. In this article, we reviewed the preventive and therapeutic effects of IGF-1 on metabolic diseases and IGF-1-mediated exercise-induced benefits.
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Fator de Crescimento Insulin-Like I , Doenças Metabólicas , Terapia por Exercício , Humanos , Fígado , Doenças Metabólicas/terapia , Músculo EsqueléticoRESUMO
Exercise training (ET) is a non-drug natural rehabilitation approach for myocardial infarction (MI). Among the numerous beneficial effects of ET, myocardial angiogenesis is indispensable. In the present study, we investigated the role and mechanism of HIF-1α and miR-126 in ET-induced MI myocardial angiogenesis which may provide new insights for MI treatment. Rat model of post-MI and human umbilical vein endothelial cells (HUVECs) were employed for our research. Histomorphology, immunohistochemistry, quantitative real-time PCR, Western blotting and small-interfering RNA (siRNA) transfection were applied to evaluate the morphological, functional and molecular mechanisms. In vivo results showed that 4-week ET could significantly increase the expression of HIF-1α and miR-126 and reduce the expression of PIK3R2 and SPRED1, while 2ME2 (HIF-1α inhibitor) partially attenuated the effect of ET treatment. In vitro results showed that HIF-1α could trigger expression of miR-126 in HUVECs in both normoxia and hypoxia, and miR-126 may be involved in the tube formation of HUVECs under hypoxia through the PI3K/AKT/eNOS and MAPK signalling pathway. In conclusion, we revealed that HIF-1α, whose expression experiences up-regulation during ET, could function as an upstream regulator to miR-126, resulting in angiogenesis promotion through the PI3K/AKT/eNOS and MAPK signalling pathway and subsequent improvement of the MI heart function.
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Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , MicroRNAs/metabolismo , Infarto do Miocárdio/metabolismo , Neovascularização Patológica , Condicionamento Físico Animal , Animais , Colágeno/química , Hemodinâmica , Células Endoteliais da Veia Umbilical Humana , Humanos , Hipóxia , Masculino , RNA Interferente Pequeno/metabolismo , Ratos , Ratos Sprague-Dawley , Transdução de Sinais , Regulação para CimaRESUMO
Two smyd1 paralogues, smyd1a and smyd1b, have been identified in zebrafish. Although Smyd1b function has been reported in fast muscle, its function in slow muscle and the function of Smyd1a, in general, are uncertain. In this study, we generated 2 smyd1a mutant alleles and analyzed the muscle defects in smyd1a and smyd1b single and double mutants in zebrafish. We demonstrated that knockout of smyd1a alone had no visible effect on muscle development and fish survival. This was in contrast to the smyd1b mutant, which exhibited skeletal and cardiac muscle defects, leading to early embryonic lethality. The smyd1a and smyd1b double mutants, however, showed a stronger muscle defect compared with smyd1a or smyd1b mutation alone, namely, the complete disruption of sarcomere organization in slow and fast muscles. Immunostaining revealed that smyd1a; smyd1b double mutations had no effect on myosin gene expression but resulted in a dramatic reduction of myosin protein levels in muscle cells of zebrafish embryos. This was accompanied by the up-regulation of hsp40 and hsp90-α1 gene expression. Together, our studies indicate that both Smyd1a and Smyd1b partake in slow and fast muscle development although Smyd1b plays a dominant role compared with Smyd1a.-Cai, M., Han, L., Liu, L., He, F., Chu, W., Zhang, J., Tian, Z., Du, S. Defective sarcomere assembly in smyd1a and smyd1b zebrafish mutants.
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Histona-Lisina N-Metiltransferase/genética , Desenvolvimento Muscular , Sarcômeros/metabolismo , Proteínas de Peixe-Zebra/genética , Animais , Proteínas de Choque Térmico HSP40/genética , Proteínas de Choque Térmico HSP40/metabolismo , Proteínas de Choque Térmico HSP90/genética , Proteínas de Choque Térmico HSP90/metabolismo , Coração/embriologia , Músculo Esquelético/embriologia , Músculo Esquelético/metabolismo , Miocárdio/metabolismo , Miosinas/metabolismo , Regulação para Cima , Peixe-ZebraRESUMO
Pathological remodeling is the main detrimental complication after myocardial infarction (MI). Overproduction of reactive oxygen species (ROS) in infarcted myocardium may contribute to this process. Adequate exercise training after MI may reduce oxidative stress-induced cardiac tissue damage and remodeling. SET and MYND domain containing 1 (Smyd1) is a muscle-specific histone methyltransferase which is upregulated by resistance training, may strengthen sarcomere assembly and myofiber folding, and may promote skeletal muscles growth and hypertrophy. However, it remains elusive if Smyd1 has similar functions in post-MI cardiac muscle and participates in exercise-induced cardioprotection. Accordingly, we investigated the effects of interval treadmill exercise on cardiac function, ROS generation, Smyd1 expression, and sarcomere assembly of F-actin in normal and infarcted hearts. Adult male rats were randomly divided into five groups (n = 10/group): control (C), exercise alone (EX), sham-operated (S), MI induced by permanent ligation of left anterior descending coronary artery (MI), and MI with interval exercise training (MI + EX). Exercise training significantly improved post-MI cardiac function and sarcomere assembly of F-actin. The cardioprotective effects were associated with increased Smyd1, Trx1, cTnI, and α-actinin expression as well as upregulated ratio of phosphorylated AMP-activated protein kinase (AMPK)/AMPK, whereas Hsp90, MuRF1, brain natriuretic peptide (BNP) expression, ROS generation, and myocardial fibrosis were attenuated. The improved post-MI cardiac function was associated with increased Smyd1 expression. In cultured H9C2 cardiomyoblasts, in vitro treatment with H2O2 (50 µmol/L) or AMP-activated protein kinase (AMPK) agonist (AICAR, 1 mmol/L) or their combination for 4 h simulated the effects of exercise on levels of ROS and Smyd1. In conclusion, we demonstrated a novel role of Smyd1 in association with post-MI exercise-induced cardioprotection. The moderate level of ROS-induced upregulation of Smyd1 may be an important target for modulating post-MI cardiac function and remodeling.
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Proteínas de Ligação a DNA/biossíntese , Regulação da Expressão Gênica no Desenvolvimento , Infarto do Miocárdio , Condicionamento Físico Animal , Remodelação Ventricular , Animais , Masculino , Infarto do Miocárdio/enzimologia , Infarto do Miocárdio/patologia , Infarto do Miocárdio/prevenção & controle , Ratos , Ratos Sprague-Dawley , Tiorredoxinas/biossínteseRESUMO
Exercise training mitigates cardiac pathological remodeling and dysfunction caused by myocardial infarction (MI), but its underlying cellular and molecular mechanisms remain elusive. Our present study in an in vivo rat model of MI determined the impact of post-MI exercise training on myocardial fibrosis, mitochondrial biogenesis, antioxidant capacity, and ventricular function. Adult male rats were randomized into: (a) Sedentary control group; (b) 4-week treadmill exercise training group; (c) Sham surgery group; (d) MI group with permanent ligation of left anterior descending coronary artery and kept sedentary during post-MI period; and (e) post-MI 4-week exercise training group. Results indicated that exercise training significantly improved post-MI left ventricular function and reduced markers of cardiac fibrosis. Exercise training also significantly attenuated MI-induced mitochondrial damage and oxidative stress, which were associated with enhanced antioxidant enzyme expression and/or activity and total antioxidant capacity in the heart. Interestingly, the adaptive activation of the SIRT1/PGC-1α/PI3K/Akt signaling following MI was further enhanced by post-MI exercise training, which is likely responsible for exercise-induced cardioprotection and mitochondrial biogenesis. In conclusion, this study has provided novel evidence on the activation of SIRT1/PGC-1α/PI3K/Akt pathway, which may mediate exercise-induced cardioprotection through reduction of cardiac fibrosis and oxidative stress, as well as improvement of mitochondrial integrity and biogenesis in post-MI myocardium.
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Infarto do Miocárdio/patologia , Infarto do Miocárdio/reabilitação , Condicionamento Físico Animal/fisiologia , Transdução de Sinais/fisiologia , Remodelação Ventricular/fisiologia , Animais , Animais Geneticamente Modificados , Cardiotônicos , Coração/fisiopatologia , Masculino , Mitocôndrias/metabolismo , Miocárdio/metabolismo , Estresse Oxidativo/fisiologia , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Ratos Sprague-Dawley , Sirtuína 1/metabolismo , Função Ventricular Esquerda/fisiologiaRESUMO
In this study, a novel composite of modified diatomite supported nanoscale zero-valent iron (mD-NZVI) was synthesized and characterized. The effects of four factors (mD-NZVI dose, temperature, contact time and initial pH) on the removal of Cr(VI) by mD-NZVI were studied by experimental work and analyzed by response surface methodology (RSM). A second-order polynomial equation fitted by Box-Behnken design was used as a statistical model and proved to be precise in describing the significance of four factors. The analysis results show that the effects of four factors on the removal efficiency of Cr(VI) were significant (F value is 19.83), initial pH was found to be the key factor. In addition, the effect of initial pH was further studied and the maximum removal efficiency of 89.34% was obtained at pH of 3, the decrease in removal efficiency with the increase in pH is a synergistic effect of Cr(VI) species, surface charge of mD-NZVI and OH- amount at different pH.
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Cromo/química , Poluentes Químicos da Água/química , Purificação da Água/métodos , Cromo/análise , Terra de Diatomáceas , Concentração de Íons de Hidrogênio , Poluentes Químicos da Água/análiseRESUMO
BACKGROUND/AIMS: Recent studies have indicated that microRNA-21 (miR-21) is involved in the inflammatory response in relation to renal disease. Sirtuin1 (SIRT1) exerts renoprotective properties by counteracting inflammation. The activation of CD40 triggers inflammation that participates in renal inflammation and injury. The relationship between miR-21, SIRT1 and CD40, however, remains elusive. METHODS: Immunohistochemistry, small-interfering RNA (siRNA) transfection, quantitative real-time PCR and western blotting were applied to assess the morphological, functional and molecular mechanisms in primary cultured renal inner medullary collecting duct (IMCD) cells. RESULTS: TNF-α induced miR-21, CD40 and acetylated-NF-κBp65 (Ac-p65) expressions and reduced SIRT1 expression in IMCD cells. miR-21 mimics increased SIRT1 expression and attenuated Ac-p65 and CD40 expressions in TNF-α-induced IMCD cells, and the corresponding changes were observed with a miR-21 inhibitor. SIRT1 overexpression or activation by SRT1720 diminished TNF-α-induced CD40 and Ac-p65 expressions, which was reversed by SIRT1 siRNA or the inhibitors Ex527 and sirtinol and augmented by pretreatment with NF-κB siRNA. Further study found that the inhibitory effect of miR-21 on Ac-p65 and CD40 expressions was impeded by pretreatment with SIRT1 siRNA. CONCLUSION: The present study indicates that miR-21 inhibits TNF-α-induced CD40 expression in IMCD cells via the SIRT1-NF-κB signalling pathway, which provides new insight in understanding the anti-inflammatory effect of miR-21.
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Antígenos CD40/metabolismo , Medula Renal/metabolismo , MicroRNAs/metabolismo , Transdução de Sinais/efeitos dos fármacos , Sirtuína 1/metabolismo , Fator de Necrose Tumoral alfa/farmacologia , Animais , Antagomirs/metabolismo , Antígenos CD40/genética , Células Cultivadas , Expressão Gênica/efeitos dos fármacos , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Medula Renal/citologia , Masculino , MicroRNAs/antagonistas & inibidores , MicroRNAs/genética , Microscopia de Fluorescência , NF-kappa B/metabolismo , Interferência de RNA , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/metabolismo , Ratos , Ratos Sprague-Dawley , Sirtuína 1/antagonistas & inibidores , Sirtuína 1/genética , Fator de Transcrição RelA/antagonistas & inibidores , Fator de Transcrição RelA/genética , Fator de Transcrição RelA/metabolismoRESUMO
Aerobic exercise has specific angiogenesis effect, also in the ischemic heart. But its mechanism has not been fully clarified. Coronary microvascular angiogenesis is the precondition of heart repair after myocardial infarction (MI). Recent studies have shown that angiogenesis is caused by endogenous stem cell/progenitor mobilization and participation, and its paracrine effects on endothelial cells (EC) function and microvascular distribution. Exercise could mobilize and activate the expression and secretion of endogenous stem cell and angiogenic factors, and affect the cardiac angiogenesis in epigenetics. Investigating the effect of different exercise methods and intension on ischemic cardiac angiogenesis and its molecular mechanism are of great significance on prevention and postoperative rehabilitation of MI. This review summarized the main mechanism, existing problems and related research progress on exercise improving ischemic cardiac angiogenesis through cardiac angiogenesis and its regulation mechanisms, endogenous stem cell mobilization and participates in angiogenesis of ischemic heart, and exercise improving ischemic cardiac angiogenesis through stem cell mobilization.
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Exercício Físico , Infarto do Miocárdio , Indutores da Angiogênese , Células Endoteliais , Mobilização de Células-Tronco Hematopoéticas , Humanos , Neovascularização PatológicaRESUMO
Appropriate exercise is the effective way for the prevention and treatment of heart diseases. Its mechanism has not been completely elucidated, and the safe and effective exercise prescription needs to be studied systematically. Exercises give rise to secretion of various cell factors, effective stem cell mobilization, physiological hypertrophy and differentiation and proliferation of cardiomyocytes. The cell sources of adult cardiomyocyte proliferation included viable cardiomyocytes, cardiac stem/progenitor cells, bone marrow stem cells, peripheral stem cells. Stem cell mobilization, homing and differentiation are the cellular basis of myocardial repair after injury. From the potential of cardiomyocyte proliferation, stem cell therapy after myocardial infarction and cardiac myocyte proliferation induced by exercise, this review focused on the stem cells mobilization promoted by aerobic exercise, the possible mechanism of cardiac repair and functional amelioration induced by the differentiation of those stem cells after myocardial infarction, the problems remained to be further studied and correlative research progress.