Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 3.149
Filtrar
1.
Med Sci Monit ; 26: e918216, 2020 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-32129321

RESUMO

BACKGROUND Chemoresistance is a primary hindrance for current cancer treatments. The influence of abnormal mitochondria in chemotherapy resistance is not well known. To explore the correlation between mitochondria and acquired chemoresistance, this work studied alterations in mitochondrial dynamics, biogenesis, and functions for paclitaxel-resistant cancer cell line A549/Taxol and its parental line A549. MATERIAL AND METHODS Mitochondrial morphology was observed by transmission electron microscopy and confocal microscopy. We measured the mitochondrial mass and mitochondrial membrane potential using fluorescent dyes. The glucose metabolic profile and ATP (adenosine triphosphate) content were determined by bioluminescent cell assays. Seahorse bio-energy analyzer XF24 was used to detect the mitochondrial respiratory function. The expressions of mitochondrial dynamics and biogenesis related genes were quantified using real-time polymerase chain reaction. RESULTS We observed fusion morphology of the mitochondrial network in A549/Taxol cells, with upregulation of fusion genes (Mfn1 and Mfn2) and downregulation of fission gene Fis1. In A549/Taxol cells, mitochondrial mass showed a significant decrease, while the mitochondrial biogenesis pathway was strongly activated. Despite the decreased mitochondrial membrane potential, the capability for mitochondrial respiration was not impaired in A549/Taxol cells. CONCLUSIONS Our study revealed a series changes of mitochondrial characteristics in paclitaxel-resistant cells. Mfn1 and Mfn2 and PGC-1alpha increased, while Fis1 expression and mitochondrial oxidative phosphorylation decreased in A549/Taxol cell lines. These changes to mitochondrial fusion, fission, and biological function contributed to the occurrence of paclitaxel resistance in tumor cells which induced paclitaxel resistance.


Assuntos
Resistencia a Medicamentos Antineoplásicos , Dinâmica Mitocondrial , Biogênese de Organelas , Paclitaxel/farmacologia , Células A549 , GTP Fosfo-Hidrolases/metabolismo , Humanos , Potencial da Membrana Mitocondrial , Microscopia Confocal , Microscopia Eletrônica de Transmissão , Mitocôndrias/ultraestrutura , Proteínas de Transporte da Membrana Mitocondrial/metabolismo , Proteínas Mitocondriais/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo
2.
Anticancer Res ; 40(2): 653-664, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32014906

RESUMO

BACKGROUND/AIM: Peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α) is a master regulator of mitochondrial biogenesis and metabolism. We investigated the effect of PGC-1α knockdown in the human colorectal cancer cell line SW620, which highly expresses PGC-1α. MATERIALS AND METHODS: We established the PGC-1α shRNA-silenced SW620 stable cell line (PGC-1α shRNA-SW620 cells) and examined cell proliferation by cell counts and carboxyfluorescein succinimidyl ester (CFSE) staining, migration by wound-healing and transwell migration assay, and invasion by transwell assays. RESULTS: PGC-1α knockdown inhibited cell proliferation, migration, and invasion in SW620 cells. Western blot analysis showed that p-AKT, p-GSK-3ß, ß-catenin, N-cadherin and vimentin expression were all reduced, but E-cadherin had increased expression in PGC-1α shRNA-SW620 cells. We also examined cell proliferation, migration, invasion and the expression of p-AKT, p-GSK-3ß, ß-catenin, N-cadherin, vimentin, and E-cadherin in PGC-1α overexpressing SW480 cells (a low PGC-1α expressing line). We observed a complete reversal of the results seen in the knockdown. CONCLUSION: PGC-1α might regulate cell proliferation and invasion via AKT/GSK-3ß/ß-catenin pathway in SW620 and SW480 cells.


Assuntos
Glicogênio Sintase Quinase 3 beta/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , beta Catenina/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/fisiologia , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Técnicas de Silenciamento de Genes , Humanos , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/biossíntese , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Transdução de Sinais , Transfecção
3.
Gene ; 735: 144394, 2020 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-31987906

RESUMO

The aim of the current study was to evaluate the effects of conjugated linoleic acid (CLA) on the expression of the genes involved in the reduction of inflammatory conditions induced by tumor necrosis factor alpha (TNF-α). To fulfill this, the C2C12 murine myoblast cell line was used. The experimental treatments consisted of 50 and 100 µM of CLA with 10, 15 and 20 ng/mL of TNF-α. Our results indicated that the concentrations of 50, 100 and 150 µM of CLA at 24 and 48 h increased the cell survival rate (p < 0.05), as compared with the control group. The effect of pre-treating CLA before the inflammation induced by TNF-α showed that the amount of cell death caused by TNF-α was inhibited in both 50 and 100 µM concentrations of CLA (p < 0.05). Modulatory effects of CLA on PGC1-α and Fndc5 transcript levels showed that the PGC1-α and Fndc5 expression levels were significantly increased 48 h after treating with 50 and 100 µM of CLA (p < 0.05). Overall, these findings indicate that using CLA could considerably improve the inflammatory condition induced by TNF-α.


Assuntos
Anti-Inflamatórios/farmacologia , Ácidos Linoleicos Conjugados/farmacologia , Mioblastos/efeitos dos fármacos , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Animais , Linhagem Celular , Camundongos , Mioblastos/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Fator de Necrose Tumoral alfa/farmacologia
4.
Cell Prolif ; 53(2): e12759, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31922310

RESUMO

OBJECTIVE: Low levels of adiponectin (APN), a biomarker of diabetes mellitus, have been implicated in the poor outcome of intracerebral haemorrhage (ICH). Herein, we aimed to demonstrate the neuroprotective effects of a blood-brain barrier-permeable APN peptide (APNp) on ICH injury in diabetic mice and explore the underlying mechanisms. MATERIALS AND METHODS: Recombinant APNp was administrated intraperitoneally to mice with collagenase-induced ICH. Neurological deficits, brain water content and neural apoptosis were assessed. Western blotting, immunofluorescence staining, quantitative RT-PCR and transmission electron microscopy were used to determine the signalling pathways affected by APNp. RESULTS: Adiponectin peptide significantly alleviated neural apoptosis, neurological deficits and brain oedema following ICH in diabetic mice. Mechanistically, APNp promoted the restoration of peroxisome proliferator-activated receptor gamma coactivator (PGC)-1α related mitochondrial function and suppressed activating transcription factor 4 (ATF4)-CCAAT-enhancer-binding protein homologous protein (CHOP)-induced neural apoptosis. Furthermore, Smad3 signalling was found to play a regulatory role in this process by transcriptionally regulating the expression of PGC-1α and ATF4. APNp significantly suppressed the elevated phosphorylation and nuclear translocation of Smad3 after ICH in diabetic mice, while the protective effects of APNp on mitochondrial and ATF4-CHOP apoptosis pathways were counteracted when Smad3 was activated by exogenous transforming growth factor (TGF)-ß1 treatment. CONCLUSIONS: Our study provided the first evidence that APNp promoted neural survival following ICH injury in the diabetic setting and revealed a novel mechanism by which APNp suppressed mitochondrial and ATF4-CHOP apoptosis pathways in a Smad3 dependent manner.


Assuntos
Adiponectina/metabolismo , Apoptose/fisiologia , Hemorragia Cerebral/metabolismo , Diabetes Mellitus Experimental/metabolismo , Mitocôndrias/metabolismo , Neurônios/metabolismo , Transdução de Sinais/fisiologia , Fator 4 Ativador da Transcrição/metabolismo , Animais , Encéfalo/metabolismo , Núcleo Celular/metabolismo , Células Cultivadas , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Transporte Proteico/fisiologia , Proteínas Recombinantes/metabolismo , Proteína Smad3/metabolismo , Fator de Transcrição CHOP/metabolismo , Fator de Crescimento Transformador beta1/metabolismo
5.
Environ Pollut ; 256: 113430, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31685329

RESUMO

Silver nanoparticles (AgNPs) are inevitably released into the environment owing to their widespread applications in industry and medicine. The potential of their toxicity has aroused a great concern. Previous studies have shown that AgNPs exposure in HepG2 cells is primarily related to the damage of mitochondria, which includes induction of mitochondrial swelling and increase of intracellular levels of reactive oxygen species (ROS), the collapse of mitochondrial membrane potential and induction of apoptosis through a mitochondrial pathway. In this study, the effects of AgNPs exposure in HepG2 cells on mitochondrial dynamics and biogenesis were investigated. AgNPs were found to induce mitochondrial morphological and structural alterations. The expressions of key proteins (Drp1, Fis1, OPA1, Mff, Mfn1, and Mfn2) related to mitochondrial fission/fusion event were changed. Especially the expression of fission-related protein 1 (p-Drp1) (Ser616) was significantly up-regulated, whereas the expression of mitochondrial biogenesis protein (PGC-1α) was reduced in AgNP-treated cells. Concomitantly, the expression of autophagy marker proteins (LC3B and p62) was increased. The results suggested that AgNPs could trigger cytotoxicity by targeting the mitochondria, resulting in the disruption of mitochondrial function, damage to the mitochondrial structure and morphology, interfering in mitochondrial dynamics and biogenesis. The mitochondria could be a critical target of AgNPs in cells. The functions of mitochondria could be used for assessing the cytotoxic effects associated with AgNPs in cells.


Assuntos
Nanopartículas Metálicas/toxicidade , Mitocôndrias/efeitos dos fármacos , Prata/toxicidade , Animais , Apoptose , Substâncias Perigosas , Células Hep G2 , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Dinâmica Mitocondrial/efeitos dos fármacos , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo , Espécies Reativas de Oxigênio/metabolismo , Testes de Toxicidade
6.
Tumori ; 106(1): 55-63, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31451071

RESUMO

PURPOSE: The present study aims to investigate the efficacy and mechanisms of peroxisome proliferator-activated receptor γ coactivator 1-α agonist, as adjuvant to programmed death-1 (PD-1) blockade in hyporesponsive lung cancer cells-derived in vivo tumor model, using bezafibrate. METHODS: Mouse Lewis lung carcinoma (LLC) xenograft models were established and treated with programmed death-ligand 1 (PD-L1) monoclonal antibodies with or without bezafibrate. Tumors or peripheral blood of mice were harvested to investigate the quality, quantity, and function as well as energetic metabolism of cytotoxic T lymphocytes (CTLs) by flow cytometry or quantitative real-time polymerase chain reaction. RESULTS: The combination of bezafibrate plus anti-PD-L1 reached synergistic tumoricidal effect in LLC xenograft mouse models, even though bezafibrate alone had no effect on tumor growth. Bezafibrate significantly facilitated CD8+ T cells infiltrating into tumor tissues by enhancing the expression of CXCL9 and CXCL10 within tumors as well as the receptor CXCR3 in infiltrating CTLs. Activated CTLs within tumors were also significantly upregulated by bezafibrate. Further data demonstrated that bezafibrate treatment could maintain the survival and functional capacity of tumor-infiltrating CTLs. Moreover, cellular reactive oxygen species in infiltrating CTLs and fatty acid oxidation (FAO)-related genes (PGC-1α, Cpt1a, and LCAD) expression within tumors were significantly increased after treatment with bezafibrate. CONCLUSIONS: Bezafibrate synergized the tumoricidal effect of PD-1 blockade in hyporesponsive lung cancer by expansion of effector CTLs within tumor microenvironment. The potential mechanism may relate to the capacity of bezafibrate in regulating FAO of tumor-infiltrating CTLs.


Assuntos
Neoplasias Pulmonares/etiologia , Neoplasias Pulmonares/metabolismo , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/agonistas , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Linfócitos T Citotóxicos/imunologia , Linfócitos T Citotóxicos/metabolismo , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Modelos Animais de Doenças , Sinergismo Farmacológico , Ácidos Graxos/metabolismo , Feminino , Humanos , Imunofenotipagem , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/mortalidade , Camundongos , Mitocôndrias/metabolismo , Oxirredução/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
7.
Food Chem Toxicol ; 135: 111043, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31836553

RESUMO

Tylorrhynchus heterochaetus (Hechong in Chinese) has been used in Chinese traditional medicine for treating various diseases. This study was aimed to assess the anti-fatigue effect of T. heterochaetus on Kunming mice and its primary mechanism of action using forced running, rotating rod and weight-loaded swimming tests. Low (2.70 mg/0.5 mL/20 g), medium (5.41 mg/0.5 mL/20 g) and high (6.58 mg/0.5 mL/20 g) doses of T. heterochaetus aqueous extract were treated to mice for 28 days. Among the doses, the low and medium doses showed significant (p ≤ 0.05) anti-fatigue effect on the weight-loaded swimming test. Also, T. heterochaetus extract showed significant (p ≤ 0.05) effects on fatigue-related blood parameters by increasing the GLU, TG and LDH levels and decreasing the LA, CK and BUN levels. The levels of liver and skeletal muscle glycogen were also significantly (p ≤ 0.05) increased after treatment. Further, on Western blot analysis, it has been found that T. heterochaetus enhanced the expressions of AMPK and PGC-1α in the liver and skeletal muscles of mice. From the study, our outcomes suggest that T. heterochaetus possess an anti-fatigue effect through the AMPK-linked pathway and thereby it can regularize the energy metabolism.


Assuntos
Adenilato Quinase/metabolismo , Produtos Biológicos/farmacologia , Fadiga/prevenção & controle , Poliquetos/química , Animais , Nitrogênio da Ureia Sanguínea , Peso Corporal/efeitos dos fármacos , Creatina Quinase/metabolismo , Glucose/metabolismo , Glicogênio/metabolismo , L-Lactato Desidrogenase/metabolismo , Ácido Láctico/metabolismo , Fígado/metabolismo , Camundongos , Músculo Esquelético/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Teste de Desempenho do Rota-Rod , Corrida , Natação , Triglicerídeos/metabolismo
8.
J Sports Sci Med ; 18(4): 596-603, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31827343

RESUMO

This study aimed to investigate the expression of PGC-1α/FNDC5/irisin induced by attenuation of high-fat diet (HFD)-induced bone accrual and determine whether swimming exercise could improve attenuating bone accrual through this mechanism. Eight-week-old Sprague-Dawley rats were divided into two groups for the first 8 weeks: CD, control diet (n = 10); and HFD, high-fat diet (n = 20). HFD-fed rats were again divided into two groups for further 8 weeks treatment: HFD (n = 10) and HFD with swimming exercise (HEx, n = 10). During this time, the CD group continuously fed the normal diet. Throughout the 16 weeks study period, the rats were weighed once every week. Samples were collected for analysis after last 8 weeks of treatment in the 16 weeks. Morphological and structural changes of the femur and tibial bone were observed using micro-CT, and Osteocalcin, CTX-1 and irisin levels in the blood were measured by enzyme-linked immunosorbent assay. The expression of IL-1, ß-catenin, FNDC5 and PGC-1α, in the femur were evaluated by immunohistochemistry. Eight weeks of HFD increased body weight and epididymal fat mass and decreased bone mineral density (BMD). Subsequent 8 weeks of swimming exercise improved obesity, BMD, bone microstructure, and bone metabolic factors in the HEx group. The irisin levels in the blood and the expressions of FNDC5 and PGC-1α in the bone were significantly lower in the HFD group than in the CD group, but elevated in the HEx group than in the HFD group. Swimming exercise is effective in improving obesity-worsened bone health and increases blood irisin and bone PGC-1α and FNDC5 levels.


Assuntos
Osso e Ossos/metabolismo , Dieta Hiperlipídica , Fibronectinas/metabolismo , Osteoporose/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Natação/fisiologia , Animais , Distribuição da Gordura Corporal , Osso e Ossos/anatomia & histologia , Osso e Ossos/diagnóstico por imagem , Ciguatoxinas/sangue , Modelos Animais de Doenças , Fêmur/anatomia & histologia , Fêmur/metabolismo , Fibronectinas/sangue , Humanos , Interleucina-1/metabolismo , Masculino , Osteocalcina/sangue , Osteoporose/sangue , Osteoporose/etiologia , Distribuição Aleatória , Ratos Sprague-Dawley , Tíbia/anatomia & histologia , Tíbia/metabolismo , Microtomografia por Raio-X , beta Catenina/metabolismo
9.
Life Sci ; 239: 116869, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31678277

RESUMO

AIM: The addition of repeated lipopolysaccharide (LPS) to chronic mild stress was recently proposed in our lab as an alternative model of depression, highlighting the possible interaction between stress and immune-inflammatory pathways in predisposing depression. Given that CMS-induced depressive behavior was previously related to impaired hippocampal energy metabolism and mitochondrial dysfunction, our current study aimed to investigate the interplay between toll-like receptor 4 (TLR4) signaling and peroxisome proliferator-activated receptor gamma coactivators-1-alpha (PGC1-α) as a physiological regulator of energy metabolism and mitochondrial biogenesis in the combined LPS/CMS model. MAIN METHODS: Male Wistar rats were exposed to either LPS (50 µg/kg i.p.) over 2 weeks, CMS protocol for 4 weeks or LPS over 2 weeks followed by 4 weeks of CMS (LPS/CMS). Three additional groups of rats were exposed to LPS/CMS protocol and treated with either pentoxifylline (PTX), fluoxetine (FLX) or a combination of both. Rats were examined for behavioral, neurochemical, gene expression and mitochondrial ultra-structural changes. KEY FINDINGS: LPS/CMS increased the expression of TLR4 and its downstream players; MyD88, NFκB and TNF-α along with an escalation in hippocampal-energy metabolism and p-AMPK. Simultaneously LPS/CMS attenuated the expression of PGC1-α/NRF1/Tfam and mt-DNA. The antidepressant (AD) 'FLX', the TNF-α inhibitor 'PTX' and their combination ameliorated the LPS/CMS-induced changes. Interestingly, all the aforementioned changes induced by the LPS/CMS combined model were significantly less than those induced by CMS alone. SIGNIFICANCE: Blocking the TLR4/NFκB signaling enhanced the activation of the PGC1-α/NRF1/Tfam and mt-DNA content independent on the activation of the energy-sensing kinase AMPK.


Assuntos
Fluoxetina/farmacologia , Mitocôndrias/efeitos dos fármacos , Pentoxifilina/farmacologia , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Estresse Psicológico/tratamento farmacológico , Estresse Psicológico/metabolismo , Receptor 4 Toll-Like/metabolismo , Animais , DNA Mitocondrial/metabolismo , Metabolismo Energético , Expressão Gênica/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Masculino , Mitocôndrias/metabolismo , NF-kappa B/metabolismo , Biogênese de Organelas , Ratos , Ratos Wistar , Transdução de Sinais/efeitos dos fármacos , Estresse Psicológico/induzido quimicamente , Fator de Necrose Tumoral alfa/metabolismo
10.
J Agric Food Chem ; 67(49): 13605-13616, 2019 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-31735033

RESUMO

Obesity is a global public health issue. Thermogenesis is a novel way to promote anti-obesity by consuming energy as heat rather than storing it as triacylglycerols. The browning program allows mitochondrial biosynthesis and thermogenesis-related gene expression to occur in subcutaneous white adipose tissue, which results in the formation of beige adipose tissue. Some phytochemicals have exerted the capability to activate the fat browning process. Resveratrol and oxyresveratrol are both natural stilbenoids that have been reported for their anti-obesity efficacy. However, the comparison between the two as they relate to thermogenesis as well as the differences in their underlying mechanisms are still not widely discussed. Our result reveals that both resveratrol and oxyresveratrol could elevate the expression of thermogenesis-related protein expression including UCP1 (uncoupling protein-1) and PRDM (PR domain containing 16) via Sirt1/PGC-1α (sirtuin 1/peroxisome proliferation gamma coactivator-1 α) activation. However, it is suggested that the transcriptional factor PPARα (peroxisome proliferator-activator receptor α) was activated by resveratrol (1.38 ± 0.07 fold) but not oxyresveratrol. Conversely, C/EBPß (CCAAT/enhancer-binding protein ß) was upregulated by oxyresveratrol (1.58 ± 0.05 fold) but not by resveratrol. On the other hand, CPT1 (carnitine palmitoyltransferase) was found to be significantly activated at lower concentrations of oxyresveratrol up to 1.89 ± 0.04 fold as compared to high-fat diet, and it could be a leading reason for UCP1 activation. Lastly, adiponectin expression was promoted in all experimental groups (1.53 ± 0.08 and 1.49 ± 0.11-fold in resveratrol (RES) and high oxyresveratrol (HOXY), respectively), which could be an activator for mitochondrial biosynthesis and UCP1 expression.


Assuntos
Obesidade/tratamento farmacológico , Obesidade/genética , Resveratrol/administração & dosagem , Termogênese/efeitos dos fármacos , Animais , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Dieta Hiperlipídica/efeitos adversos , Metabolismo Energético/efeitos dos fármacos , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Obesos , Obesidade/metabolismo , Obesidade/fisiopatologia , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Sirtuína 1/genética , Sirtuína 1/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteína Desacopladora 1/genética , Proteína Desacopladora 1/metabolismo
11.
PLoS Biol ; 17(10): e3000467, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31589602

RESUMO

Skeletal muscles consist of fibers of differing metabolic activities and contractility, which become remodeled in response to chronic exercise, but the epigenomic basis for muscle identity and adaptation remains poorly understood. Here, we used chromatin immunoprecipitation sequencing of dimethylated histone 3 lysine 4 and acetylated histone 3 lysine 27 as well as transposase-accessible chromatin profiling to dissect cis-regulatory networks across muscle groups. We demonstrate that in vivo enhancers specify muscles in accordance with myofiber composition, show little resemblance to cultured myotube enhancers, and identify glycolytic and oxidative muscle-specific regulators. Moreover, we find that voluntary wheel running and muscle-specific peroxisome proliferator-activated receptor gamma coactivator-1 alpha (Pgc1a) transgenic (mTg) overexpression, which stimulate endurance performance in mice, result in markedly different changes to the epigenome. Exercise predominantly leads to enhancer hypoacetylation, whereas mTg causes hyperacetylation at different sites. Integrative analysis of regulatory regions and gene expression revealed that exercise and mTg are each associated with myocyte enhancer factor (MEF) 2 and estrogen-related receptor (ERR) signaling and transcription of genes promoting oxidative metabolism. However, exercise was additionally associated with regulation by retinoid X receptor (RXR), jun proto-oncogene (JUN), sine oculis homeobox factor (SIX), and other factors. Overall, our work defines the unique enhancer repertoires of skeletal muscles in vivo and reveals that divergent exercise-induced or PGC1α-driven epigenomic programs direct partially convergent transcriptional networks.


Assuntos
Epigênese Genética , Histonas/genética , Células Musculares/metabolismo , Músculo Esquelético/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Condicionamento Físico Animal , Acetilação , Animais , Reprogramação Celular , Cromatina/química , Cromatina/metabolismo , Elementos Facilitadores Genéticos , Glicólise/genética , Histonas/metabolismo , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Fatores de Transcrição MEF2/genética , Fatores de Transcrição MEF2/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Células Musculares/citologia , Músculo Esquelético/citologia , Fosforilação Oxidativa , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Proteínas Proto-Oncogênicas c-jun/genética , Proteínas Proto-Oncogênicas c-jun/metabolismo , Receptores Estrogênicos/genética , Receptores Estrogênicos/metabolismo , Receptores X Retinoide/genética , Receptores X Retinoide/metabolismo , Transdução de Sinais
12.
Mol Cell ; 76(6): 885-895.e7, 2019 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-31629659

RESUMO

Hypoxia, which occurs during tumor growth, triggers complex adaptive responses in which peroxisome proliferator-activated receptor gamma coactivator-1 alpha (PGC-1α) plays a critical role in mitochondrial biogenesis and oxidative metabolism. However, how PGC-1α is regulated in response to oxygen availability remains unclear. We demonstrated that lysine demethylase 3A (KDM3A) binds to PGC-1α and demethylates monomethylated lysine (K) 224 of PGC-1α under normoxic conditions. Hypoxic stimulation inhibits KDM3A, which has a high KM of oxygen for its activity, and enhances PGC-1α K224 monomethylation. This modification decreases PGC-1α's activity required for NRF1- and NRF2-dependent transcriptional regulation of TFAM, TFB1M, and TFB2M, resulting in reduced mitochondrial biogenesis. Expression of PGC-1α K224R mutant significantly increases mitochondrial biogenesis, reactive oxygen species (ROS) production, and tumor cell apoptosis under hypoxia and inhibits brain tumor growth in mice. This study revealed that PGC-1α monomethylation, which is dependent on oxygen availability-regulated KDM3A, plays a critical role in the regulation of mitochondrial biogenesis.


Assuntos
Neoplasias Encefálicas/enzimologia , Histona Desmetilases com o Domínio Jumonji/metabolismo , Mitocôndrias/enzimologia , Biogênese de Organelas , Oxigênio/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Processamento de Proteína Pós-Traducional , Animais , Apoptose , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Proliferação de Células , Feminino , Regulação Neoplásica da Expressão Gênica , Células HEK293 , Células HeLa , Células Hep G2 , Humanos , Histona Desmetilases com o Domínio Jumonji/genética , Metilação , Camundongos Endogâmicos BALB C , Camundongos Nus , Mitocôndrias/patologia , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Carga Tumoral , Hipóxia Tumoral , Microambiente Tumoral
13.
Int J Mol Sci ; 20(20)2019 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-31614723

RESUMO

Post-translational modulation of peptidylprolyl isomerase Pin1 might link impaired glucose metabolism and neurodegeneration, being Pin1 effectors target for the glucagon-Like-Peptide1 analog liraglutide. We tested the hypotheses in Pin1 silenced cells (SH-SY5Y) treated with 2-deoxy-d-glucose (2DG) and methylglyoxal (MG), stressors causing altered glucose trafficking, glucotoxicity and protein glycation. Rescue by liraglutide was investigated. Pin1 silencing caused increased levels of reactive oxygen species, upregulated energy metabolism as suggested by raised levels of total ATP content and mRNA of SIRT1, PGC1α, NRF1; enhanced mitochondrial fission events as supported by raised protein expression of FIS1 and DRP1. 2DG and MG reduced significantly cell viability in all the cell lines. In Pin1 KD clones, 2DG exacerbated altered mitochondrial dynamics causing higher rate of fission events. Liraglutide influenced insulin signaling pathway (GSK3b/Akt); improved cell viability also in cells treated with 2DG; but it did not revert mitochondrial dysfunction in Pin1 KD model. In cells treated with MG, liraglutide enhanced cell viability, reduced ROS levels and cell death (AnnexinV/PI); and trended to reduce anti-apoptotic signals (BAX, BCL2, CASP3). Pin1 silencing mimics neuronal metabolic impairment of patients with impaired glucose metabolism and neurodegeneration. Liraglutide rescues to some extent cellular dysfunctions induced by Pin1 silencing.


Assuntos
Liraglutida/farmacologia , Peptidilprolil Isomerase de Interação com NIMA/genética , Fármacos Neuroprotetores/farmacologia , Trifosfato de Adenosina/metabolismo , Apoptose , Linhagem Celular Tumoral , Desoxiglucose/toxicidade , Inativação Gênica , Humanos , Insulina/metabolismo , Peptidilprolil Isomerase de Interação com NIMA/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Fator 1 Nuclear Respiratório/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Aldeído Pirúvico/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Sirtuína 1/genética , Sirtuína 1/metabolismo
14.
Int J Mol Sci ; 20(20)2019 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-31614978

RESUMO

TGF-ß/Smad signaling is a major pathway in progressive fibrotic processes, and further studies on the molecular mechanisms of TGF-ß/Smad signaling are still needed for their therapeutic targeting. Recently, peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α) was shown to improve renal fibrosis, making it an attractive target for chronic kidney diseases (CKDs). Here, we show the mechanism by which PGC-1α regulates the TGF-ß/Smad signaling pathway using HK-2 cell lines stably overexpressing empty vector (mock cells) or human PGC1α (PGC1α cells). Stable PGC-1α overexpression negatively regulated the expression of TGF-ß-induced epithelial-mesenchymal transition (EMT) markers (fibronectin, E-cadherin, vimentin, and α-SMA) and EMT-related transcription factors (Snail and Slug) compared to mock cells, inhibiting fibrotic progression. Interestingly, among molecules upstream of Smad2/3 activation, the gene expression of only TGFßRI, but not TGFßRII, was downregulated in PGC-1α cells. In addition, the downregulation of TGFßRI by PGC-1α was associated with the upregulation of let-7b/c, miRNA for which the 3' untranslated region (UTR) of TGFßRI contains a binding site. In conclusion, PGC-1α suppresses TGF-ß/Smad signaling activation via targeting TGFßRI downregulation by let-7b/c upregulation.


Assuntos
MicroRNAs/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Receptor do Fator de Crescimento Transformador beta Tipo I/genética , Insuficiência Renal Crônica/genética , Sítios de Ligação/genética , Linhagem Celular , Proliferação de Células/genética , Transição Epitelial-Mesenquimal/genética , Regulação da Expressão Gênica/genética , Humanos , Peroxissomos/genética , Receptor do Fator de Crescimento Transformador beta Tipo II/genética , Insuficiência Renal Crônica/patologia , Transdução de Sinais , Proteínas Smad/genética , Fatores de Transcrição da Família Snail/genética , Fator de Crescimento Transformador beta/genética
15.
Food Funct ; 10(9): 6157-6169, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31501849

RESUMO

Chicoric acid (CA), a major nutraceutical component of a typical Mediterranean vegetable, chicory, possesses excellent antioxidant and anti-inflammatory bioactivities. This work aimed to elucidate the effects of CA on neuron survival against inflammation and the underlying molecular mechanisms. Results demonstrated that CA promoted SH-SY5Y cells' autophagic vesicle formation, up-regulated autophagic elongation phase related gene expressions, and inhibited apoptosis stimulated by microglial conditioned culture medium (MCM). In addition, CA significantly improved mitochondrial function and regulated redox homeostasis related signaling pathways such as MAPKs and PI3K/AKT. MCM with CA notably increased the expressions of PGC-1α, SIRT1 and enhanced the phosphorylation of AMPK, promoting energy metabolism. On the other hand, the underlying mechanisms of the intervention of CA in MCM-induced cell apoptosis were partly due to its direct protective effect on SH-SY5Y cells and inhibition of microglial inflammatory factor release. This establishes a theoretical foundation for neuro-nutrition intervention studies of natural functional food components, and provides new clues for developing health foods containing CA.


Assuntos
Apoptose/efeitos dos fármacos , Ácidos Cafeicos/farmacologia , Metabolismo Energético/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Succinatos/farmacologia , Ácidos Cafeicos/química , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Humanos , Mitocôndrias/metabolismo , Neurônios/citologia , Neurônios/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Sirtuína 1/genética , Sirtuína 1/metabolismo , Succinatos/química
16.
Endocrinology ; 160(12): 2773-2786, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31555811

RESUMO

Protein arginine methyltransferases (PRMTs) are enzymes that regulate the evolutionarily conserved process of arginine methylation. It has been reported that PRMTs are involved in many metabolic regulatory pathways. However, until now, their roles in adipocyte function, especially browning and thermogenesis, have not been evaluated. Even though Prmt1 adipocyte-specific-deleted mice (Prmt1fl/flAQcre) appeared normal at basal level, following cold exposure or ß-adrenergic stimulation, impaired induction of the thermogenic program was observed in both the interscapular brown adipose tissue and inguinal white adipose tissue of Prmt1fl/flAQcre mice compared with littermate controls. Different splicing variants of Prmt1 have been reported. Among them, PRMT1 variant 1 and PRMT1 variant 2 (PRMT1V2) are well conserved between humans and mice. Both variants contribute to the activation of thermogenic fat, with PRMT1V2 playing a more dominant role. Mechanistic studies using cultured murine and human adipocytes revealed that PRMT1V2 mediates thermogenic fat activation through PGC1α, a transcriptional coactivator that has been shown to play a key role in mitochondrial biogenesis. To our knowledge, our data are the first to demonstrate that PRMT1 plays a regulatory role in thermogenic fat function. These findings suggest that modulating PRMT1 activity may represent new avenues to regulate thermogenic fat and mediate energy homeostasis. This function is conserved in human primary adipocytes, suggesting that further investigation of this pathway may ultimately lead to therapeutic strategies against human obesity and associated metabolic disorders.


Assuntos
Adipócitos Bege/enzimologia , Adipócitos Marrons/enzimologia , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Proteína-Arginina N-Metiltransferases/metabolismo , Termogênese , Aclimatação , Animais , Feminino , Regulação da Expressão Gênica , Humanos , Masculino , Camundongos , Cultura Primária de Células
17.
Biomed Pharmacother ; 118: 109407, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31545290

RESUMO

The purpose of this study was to observe the functions of preconditioning with endoplasmic reticulum stress (ERS) whether alleviated heart ischemia/reperfusion injury (HI/RI) via modulating IRE1/ATF6/RACK1/PERK and PGC-1α expressions in diabetes mellitus (DM) or not. Diabetic rats were pretreated with 0.6 mg/kg tunicamycin (TM, 0.6 mg/kg tunicamycin was administered via intraperitoneal injection 30 minutes prior to the I/R procedures), and then subjected to 45 minutes of ischemia and 3 hours of reperfusion. Blood and myocardial tissues were collected, myocardial pathological injuries were investigated, serum creatine kinase-MB (CK-MB) and cardiac troponin T (cTnT) levels were measured, left ventricular systolic pressure (LVSP), left ventricular end diastolic pressure (LVEDP), maximum rate of left ventricular pressure rise (+dp/dtmax) and maximum rate of left ventricular pressure drop (-dp/dtmax) were evaluated, reactive oxygen species (ROS) and caspase-3 levels were observed, ΔΨm level and ROS expression were measured, and activated transcript factor 6 (ATF6), receptor for activated C kinase 1 (RACK1), PRK-like ER kinase (PERK), glucose regulated protein 78 (GRP78) and peroxisome proliferator-activated receptor γ co-activator 1-α (PGC-1α) expressions were assessed. The TM ameliorated the pathological damages, reduced myocardial oxidative stress damages, restrained apoptosis, and upregulated the expressions of ATF6, RACK1, PERK, GRP78 and PGC-1α compared with those of the ischemia/reperfusion (I/R) group in DM. This study suggested the preconditioning with endoplasmic reticulum stress (TM) strategy that could enhance protection against HI/RI in DM in clinical myocardial diseases.


Assuntos
Fator 6 Ativador da Transcrição/metabolismo , Diabetes Mellitus Experimental/patologia , Estresse do Retículo Endoplasmático , Proteínas de Membrana/metabolismo , Traumatismo por Reperfusão Miocárdica/patologia , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Receptores de Quinase C Ativada/metabolismo , eIF-2 Quinase/metabolismo , Animais , Creatina Quinase/sangue , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/complicações , Proteínas de Choque Térmico/metabolismo , Masculino , Potencial da Membrana Mitocondrial , Traumatismo por Reperfusão Miocárdica/sangue , Traumatismo por Reperfusão Miocárdica/complicações , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Troponina T/metabolismo
19.
Mar Drugs ; 17(9)2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31480724

RESUMO

Mitochondria are considered to be the powerhouses of cells. They are the most commonly damaged organelles within dopaminergic neurons in patients with Parkinson's disease (PD). Despite the importance of protecting neuronal mitochondria in PD patients, the detailed mechanisms underlying mitochondrial dysfunction during pathogenesis and pathophysiological progression of PD have not yet been elucidated. We investigated the protective action of fucoidan against the detrimental action of 1-methyl-4-phenyl-pyridinium (MPP+), a neurotoxin used to model PD, in the mitochondria of SH-SY5Y neural cells. Fucoidan increased the expression of peroxisome proliferator-activated receptor gamma coactivator-1 alpha (PGC-1α) and protected the cells from MPP+-induced apoptosis by upregulating the 5' adenosine monophosphate-activated protein kinase (AMPK)-PGC-1α axis. These effects were blocked by the silencing of the PGC-1α axis. These results indicated that fucoidan protects SH-SY5Y cells from mitochondrial dysfunction and cell death caused by MPP+ treatment, via the AMPK-PGC-1α axis. These findings also suggest that fucoidan could potentially be used as a therapeutic agent for PD.


Assuntos
1-Metil-4-fenilpiridínio/farmacologia , Morte Celular/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Doenças Mitocondriais/tratamento farmacológico , Neurônios/efeitos dos fármacos , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Polissacarídeos/farmacologia , Adenilato Quinase/metabolismo , Linhagem Celular Tumoral , Neurônios Dopaminérgicos/efeitos dos fármacos , Humanos , Mitocôndrias/metabolismo , Doenças Mitocondriais/metabolismo , Neurônios/metabolismo , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/metabolismo
20.
Redox Biol ; 26: 101307, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31473487

RESUMO

Idiopathic pulmonary fibrosis (IPF) is a progressive disease with an increased mortality. Metabolic reprogramming has a critical role in multiple chronic diseases. Lung macrophages expressing the mitochondrial calcium uniporter (MCU) have a critical role in fibrotic repair, but the contribution of MCU in macrophage metabolism is not known. Here, we show that MCU regulates peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α) and metabolic reprogramming to fatty acid oxidation (FAO) in macrophages. MCU regulated PGC-1α expression by increasing the phosphorylation of ATF-2 by the p38 MAPK in a redox-dependent manner. The expression and activation of PGC-1α via the p38 MAPK was regulated by MCU-mediated mitochondrial calcium uptake, which is linked to increased mitochondrial ROS (mtROS) production. Mice harboring a conditional expression of dominant-negative MCU in macrophages had a marked reduction in mtROS and FAO and were protected from pulmonary fibrosis. Moreover, IPF lung macrophages had evidence of increased MCU and mitochondrial calcium, increased phosphorylation of ATF2 and p38, as well as increased expression of PGC-1α. These observations suggest that macrophage MCU-mediated metabolic reprogramming contributes to fibrotic repair after lung injury.


Assuntos
Canais de Cálcio/metabolismo , Metabolismo Energético , Regulação da Expressão Gênica , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Fibrose Pulmonar/genética , Fibrose Pulmonar/metabolismo , Adulto , Idoso , Animais , Cálcio/metabolismo , Modelos Animais de Doenças , Feminino , Humanos , Macrófagos Alveolares/metabolismo , Macrófagos Alveolares/patologia , Masculino , Camundongos , Pessoa de Meia-Idade , Mitocôndrias/genética , Mitocôndrias/metabolismo , Oxirredutases atuantes sobre Doadores de Grupo CH-NH2/metabolismo , Consumo de Oxigênio , Fenótipo , Fibrose Pulmonar/patologia , Espécies Reativas de Oxigênio/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA