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1.
Int J Mol Med ; 47(4): 1, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33537813

RESUMO

The activation of oxidative stress is a primary cause of chondrocyte apoptosis in osteoarthritis (OA). The 78­kDa glucose­regulated protein (GRP78)/mammalian target of rapamycin (mTOR) signaling pathway has been demonstrated to be linked with the endoplasmic reticulum (ER) and autophagy. Hydrogen sulfide (H2S) has been reported to exert antioxidant effects. The present study investigated oxidative stress levels via 2',7'­dichlorofluorescin diacetate and MitoSOX staining, apoptosis rates via flow cytometry and the expression levels of ER stress­related proteins in GYY4137 (donor of H2S)­treated chondrocytes (CHs). CHs were isolated from the bilateral hip joints of male rats to examine mitochondrial permeability transition pore opening­ and mTOR signaling pathway­related proteins. The results demonstrated that tert­Butyl hydroperoxide (TBHP) increased CH apoptosis, and treatment with GYY4137 ameliorated TBHP­mediated the generation of ROS and CH apoptosis. Moreover, TBHP­treated CHs displayed elevated ER stress sensor expression levels and apoptotic rates; however, the TBHP­induced protein expression levels were decreased following GYY4137 treatment. In the present study, treatment with either GYY4137 or transfection with GRP78 siRNA both suppressed the activation of p­P70S6k and p­mTOR. H2S played an important role in regulating ER stress in TBHP­stimulated CHs. GYY4137 promoted autophagy, which was accompanied by the inhibition of ER stress. On the whole, the present study demonstrates that TBHP­induced oxidative stress stimulates ER interactions and CH apoptosis, which are suppressed by exogenous H2S via modulating the GRP78/mTOR signaling pathway.


Assuntos
Condrócitos/metabolismo , Condrócitos/patologia , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Proteínas de Choque Térmico/metabolismo , Sulfeto de Hidrogênio/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo , Animais , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Hipóxia Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cloroquina/farmacologia , Condrócitos/efeitos dos fármacos , Citoproteção/efeitos dos fármacos , Masculino , Morfolinas/química , Morfolinas/farmacologia , Compostos Organotiofosforados/química , Compostos Organotiofosforados/farmacologia , Peróxidos/farmacologia , Substâncias Protetoras/farmacologia , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos
2.
Toxicol Lett ; 340: 33-42, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33421550

RESUMO

Toxic and volatile chemicals are widely used in household products and previously used as warfare agents, causing a public health threat worldwide. This study aimed to evaluate the extent of injury and mechanisms of acrolein toxicity in the cornea. Primary human corneal stromal fibroblasts cultures (hCSFs) from human donor cornea were cultured and exposed to acrolein toxicity with -/+ N-acetylcysteine (NAC) to study the mode of action in the presence of Buthionine sulphoximine (BSO). PrestoBlue and MTT assays were used to optimize acrolein, NAC, and BSO doses for hCSFs. Cell-based assays and qRT-PCR analyses were performed to understand the acrolein toxicity and mechanisms. Acrolein exposure leads to an increased reactive oxygen species (ROS), compromised glutathione (GSH) levels, and mitochondrial dysfunction. The TUNEL and caspase assays showed that acrolein caused cell death in hCSFs. These deleterious effects can be mitigated using NAC in hCSFs, suggesting that GSH can be a potential target for acrolein toxicity in the cornea.


Assuntos
Acroleína/toxicidade , Córnea/citologia , Fibroblastos/efeitos dos fármacos , Glutationa/metabolismo , Caspase 3/genética , Caspase 3/metabolismo , Caspase 7/genética , Caspase 7/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Citoproteção/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Peroxidação de Lipídeos , Lipídeos/química , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Estresse Oxidativo , Espécies Reativas de Oxigênio
3.
Am J Physiol Cell Physiol ; 320(2): C216-C224, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33326314

RESUMO

Leukocyte adhesion to the endothelium is an important early step in the initiation and progression of sepsis. The endothelial glycocalyx layer (EGL) has been implicated in neutrophil adhesion and barrier dysfunction, but studies in this area are few. In this report, we examine the hypothesis that damage to the structure of the EGL caused by inflammation leads to increased leukocyte adhesion and endothelial barrier dysfunction. We used human umbilical vein endothelial cells enzymatically treated to remove the EGL components hyaluronic acid (HA) and heparan sulfate (HS) as a model for EGL damage. Using atomic force microscopy, we show reductions in EGL thickness after removal of either HA or HS individually, but the largest decrease, comparable with TNF-α treatment, was observed when both HA and HS were removed. Interestingly, removal of HS or HA individually did not affect neutrophil adhesion significantly, but removal of both constituents resulted in increased neutrophil adhesion. To test EGL contributions to endothelial barrier properties, we measured transendothelial electrical resistance (TEER) and diffusion of fluorescently labeled dextran (10 kDa molecular weight) across the monolayer. Removal of EGL components decreased TEER but had an insignificant effect on dextran diffusion rates. The reduction in TEER suggests that disruption of the EGL may predispose endothelial cells to increased rates of fluid leakage. These data support the view that damage to the EGL during inflammation has significant effects on the accessibility of adhesion molecules, likely facilitates leukocyte adhesion, and may also contribute to increased rates of fluid transport into tissues.


Assuntos
Citoproteção/fisiologia , Glicocálix/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Mediadores da Inflamação/metabolismo , Mediadores da Inflamação/toxicidade , Citoproteção/efeitos dos fármacos , Glicocálix/química , Glicocálix/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/química , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Neutrófilos/química , Neutrófilos/efeitos dos fármacos , Neutrófilos/metabolismo
4.
Food Chem ; 338: 128116, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33092008

RESUMO

In this study, we investigated the cytoprotective effects of dihydromyricetin (DHM) against deoxynivalenol (DON)-induced toxicity and accompanied metabolic pathway changes in porcine jejunum epithelial cells (IPEC-J2). The cells were incubated in 250 ng/ml DON cotreated with 40 µM DHM, followed by toxicity analysis, oxidative stress reaction analysis, inflammatory response analysis and metabolomic analysis. The results showed that DHM significantly increased the cell viability (P < 0.01), the intracellular GSH level (P < 0.01) and decreased the intracellular ROS level (P < 0.01), the secretion of TNF-α, IL-8 (P < 0.01) and the apoptotic cell percentages (P < 0.01) in IPEC-J2 cells compared to that in the DON group. Metabolomic analysis revealed that DHM recovered the disorder of metabolic pathways such as glutamate metabolism, arachidonic metabolism and histidine metabolism caused by DON. In summary, DHM alleviated cell injury induced by DON and it is possibly through its antioxidant activity, anti-inflammatory activity or ability to regulate metabolic pathways.


Assuntos
Citoproteção/efeitos dos fármacos , Células Epiteliais/citologia , Células Epiteliais/efeitos dos fármacos , Flavonóis/farmacologia , Tricotecenos/farmacologia , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Células Epiteliais/metabolismo , Suínos
5.
Int J Nanomedicine ; 15: 4859-4876, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32764923

RESUMO

Introduction: CoenzymeQ10 (CoQ10) is a well-known antioxidant and anti-inflammatory agent with cardioprotective properties. However, clinical trials based on its oral administration have failed to provide significant effect on cardiac functionality. The main limitation of CoQ10 is based on its very low oral bioavailability and instability that limit dramatically its effects as a cardioprotective agent. Herein, we loaded CoQ10 in high bioavailable nano-emulsions (NEs) coated with chitosan or chitosan and hyaluronic acid in order to improve its performance. Methods: We tested cardioprotective and hepatoprotective effects of CoQ10-loaded nano-carriers against Doxorubicin and Trastuzumab toxicities in cardiomyocytes and liver cells through analysis of cell viability, lipid peroxidation, expression of leukotrienes, p65/NF-kB and pro-inflammatory cytokines involved in anticancer-induced cardio and hepatotoxicity. Results: Nano-carriers showed high stability and loading ability and increased cell viability both in hepatocytes and cardiomyocytes during anticancer treatments. We observed that these effects are mediated by the inhibition of lipid peroxidation and reduction of the inflammation. CoQ10-loaded nano-emulsions showed also strong anti-inflammatory effects reducing leukotriene B4 and p65/NF-κB expression and Interleukin 1ß and 6 production during anticancer treatments. Discussion: Anthracyclines and Human epidermal growth factor receptor (HER2) inhibitors have shown significant anticancer effects in clinical practice but their use is characterized by cardiotoxicity and hepatotoxicity. Nano-carriers loaded with CoQ10 showed cardio and hepatoprotective properties mediated by reduction of oxidative damages and pro-inflammatory mediators. These results set the stage for preclinical studies of cardio and hepatoprotection in HER2+ breast cancer-bearing mice treated with Doxorubicin and Trastuzumab.


Assuntos
Antraciclinas/efeitos adversos , Fígado/citologia , Miócitos Cardíacos/efeitos dos fármacos , Nanoestruturas/química , Trastuzumab/efeitos adversos , Ubiquinona/análogos & derivados , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Cápsulas , Cardiotônicos/química , Cardiotônicos/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Citoproteção/efeitos dos fármacos , Feminino , Hepatócitos/metabolismo , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Camundongos , Miócitos Cardíacos/citologia , Miócitos Cardíacos/metabolismo , Ubiquinona/química , Ubiquinona/farmacologia
6.
Nat Commun ; 11(1): 3427, 2020 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-32647171

RESUMO

The contribution of inflammation to the chronic joint disease osteoarthritis (OA) is unclear, and this lack of clarity is detrimental to efforts to identify therapeutic targets. Here we show that chondrocytes under inflammatory conditions undergo a metabolic shift that is regulated by NF-κB activation, leading to reprogramming of cell metabolism towards glycolysis and lactate dehydrogenase A (LDHA). Inflammation and metabolism can reciprocally modulate each other to regulate cartilage degradation. LDHA binds to NADH and promotes reactive oxygen species (ROS) to induce catabolic changes through stabilization of IκB-ζ, a critical pro-inflammatory mediator in chondrocytes. IκB-ζ is regulated bi-modally at the stages of transcription and protein degradation. Overall, this work highlights the function of NF-κB activity in the OA joint as well as a ROS promoting function for LDHA and identifies LDHA as a potential therapeutic target for OA treatment.


Assuntos
Condrócitos/metabolismo , Lactato Desidrogenase 5/metabolismo , Terapia de Alvo Molecular , Osteoartrite/tratamento farmacológico , Espécies Reativas de Oxigênio/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Aerobiose , Animais , Cartilagem Articular/patologia , Células Cultivadas , Condrócitos/efeitos dos fármacos , Condrócitos/patologia , Citoproteção/efeitos dos fármacos , Deleção de Genes , Regulação da Expressão Gênica/efeitos dos fármacos , Glicólise/efeitos dos fármacos , Humanos , Inflamação/metabolismo , Inflamação/patologia , Interleucina-1beta/farmacologia , Articulação do Joelho/patologia , Meniscos Tibiais/cirurgia , Redes e Vias Metabólicas/efeitos dos fármacos , Camundongos Endogâmicos C57BL , NAD/metabolismo , NF-kappa B/metabolismo , Osteoartrite/genética , Osteoartrite/patologia
7.
J Pharmacol Sci ; 144(1): 43-51, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32653340

RESUMO

Platelet activation is the primary cause of thrombosis. The P2X7 receptor (P2X7R) is a therapeutic target of thrombosis. However, it is still unknown whether P2X7R activation affects platelet thrombus. Our molecular docking results showed that entecavir as a P2X7R antagonist interacted perfectly with the human P2X7R (hP2X7R) in silico simulation studies. Furthermore, our experimental data revealed that entecavir could act as a P2X7R antagonist to exert cytoprotective effects against platelet activation via protecting mitochondrial function, improving lipid peroxidation and increasing antioxidant activity. Correlated with this, entecavir inhibited platelet aggregation, dense-granule secretion, P-selectin expression, integrin activation and Ca2+ increase. In experimental mouse model, entecavir could significantly inhibit arteriovenous thrombosis and prolong the bleeding time. Furthermore, we found that entecavir had no significant effect on prothrombin time (PT), activated partial thrombin time (APTT), thrombin time (TT), fibrinogen (FIB), mean platelet volume (MPV) and platelet counts (PLT). This study demonstrates that entecavir markedly prevents platelet activation and thrombosis through inhibiting P2X7R without affecting coagulation system. Therefore, entecavir may be a potential candidate for treating thrombosis disease.


Assuntos
Guanina/análogos & derivados , Ativação Plaquetária/efeitos dos fármacos , Antagonistas do Receptor Purinérgico P2X/farmacologia , Antagonistas do Receptor Purinérgico P2X/uso terapêutico , Receptores Purinérgicos P2X7 , Trombose/prevenção & controle , Animais , Antioxidantes , Tempo de Sangramento , Coagulação Sanguínea/efeitos dos fármacos , Citoproteção/efeitos dos fármacos , Modelos Animais de Doenças , Guanina/farmacologia , Guanina/uso terapêutico , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Camundongos Endogâmicos C57BL , Simulação de Acoplamento Molecular , Agregação Plaquetária/efeitos dos fármacos , Trombose/sangue
8.
J Biosci Bioeng ; 130(3): 283-289, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32507385

RESUMO

A novel exopolysaccharide (EPS) from Paenibacillus polymyxa PYQ1 was extracted, well purified and characterized. This EPS was homogeneous glucomannan-type polysaccharide with the average molecular weight of 4.38 × 106 Da. Structural characterization indicated that the monosaccharides of EPS were pyranoses connected by ß-glycosidic linkages. Furthermore, our results showed the protective benefits of EPS against UVC induced cytotoxicity in HaCaT cells through scavenging excessive reactive oxygen species, mitigating the decrease of mitochondrial membrane potential, improving catalase activity and maintaining membrane integrity. Taken together, this study qualified EPS from P. polymyxa PYQ1 was a promising natural polymer which worth further investigation as a skin-care agent.


Assuntos
Citoproteção/efeitos dos fármacos , Paenibacillus polymyxa/metabolismo , Polissacarídeos Bacterianos/isolamento & purificação , Polissacarídeos Bacterianos/farmacologia , Raios Ultravioleta/efeitos adversos , Catalase/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Potencial da Membrana Mitocondrial/efeitos da radiação , Peso Molecular , Monossacarídeos/análise , Polissacarídeos Bacterianos/biossíntese , Polissacarídeos Bacterianos/química , Espécies Reativas de Oxigênio/metabolismo
9.
Nat Commun ; 11(1): 2376, 2020 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-32398747

RESUMO

Naked mole-rat (NMR), the longest-living rodent, produces very-high-molecular-mass hyaluronan (vHMM-HA), compared to other mammalian species. However, it is unclear if exceptional polymer length of vHMM-HA is important for longevity. Here, we show that vHMM-HA (>6.1 MDa) has superior cytoprotective properties compared to the shorter HMM-HA. It protects not only NMR cells, but also mouse and human cells from stress-induced cell-cycle arrest and cell death in a polymer length-dependent manner. The cytoprotective effect is dependent on the major HA-receptor, CD44. We find that vHMM-HA suppresses CD44 protein-protein interactions, whereas HMM-HA promotes them. As a result, vHMM-HA and HMM-HA induce opposing effects on the expression of CD44-dependent genes, which are associated with the p53 pathway. Concomitantly, vHMM-HA partially attenuates p53 and protects cells from stress in a p53-dependent manner. Our results implicate vHMM-HA in anti-aging mechanisms and suggest the potential applications of vHMM-HA for enhancing cellular stress resistance.


Assuntos
Citoproteção/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Receptores de Hialuronatos/metabolismo , Ácido Hialurônico/farmacologia , Animais , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/fisiologia , Linhagem Celular , Citoproteção/fisiologia , Regulação da Expressão Gênica/fisiologia , Técnicas de Inativação de Genes , Humanos , Ácido Hialurônico/química , Ácido Hialurônico/isolamento & purificação , Ácido Hialurônico/metabolismo , Longevidade/fisiologia , Camundongos , Ratos-Toupeira/fisiologia , Peso Molecular , Cultura Primária de Células , Mapas de Interação de Proteínas/efeitos dos fármacos , RNA-Seq , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Especificidade da Espécie , Estresse Fisiológico , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
10.
Exp Mol Pathol ; 115: 104445, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32335083

RESUMO

OBJECTIVE: Since microRNAs (miRNAs) represent as effective therapeutic targets for diabetic retinopathy (DR), we identified aberrantly expressed miRNAs related to cellular dysfunction in DR and further detected their potential targets. This study aimed to explore the synergistic effect of miR-216a, inducible nitric oxide synthase 2 (NOS2) and the Janus kinase/signal transducer and activator of transcription (JAK/STAT) pathway on human retinal microvascular endothelial cell (HRMEC) injury in DR. METHODS: The differentially expressed genes in DR were obtained by GEO database, and the downstream signaling pathways and upstream targeted miRNAs were obtained through bioinformatics analysis. Subsequently, a DR model rat was established, and the target miR-216a was overexpressed to observe the pathological and morphological changes of the rat retina and the levels of inflammatory factors. Then, HRMECs were extracted and added with d-Glucose, and then transfected with miR-216a, NOS2 or adding JAK/STAT signaling pathway specific inhibitor to observe changes in cell activity and inflammatory damage. RESULTS: NOS2 was significantly upregulated, and the JAK/STAT signaling pathway was significantly activated in DR. miR-216a targeted NOS2, which played a protective role in the retina of DR rats. Moreover, in cell experiments, overexpression of miR-216a promoted the viability of HRMECs under d-glucose treatment, and inhibited NOS2 expression and the JAK/STAT signaling pathway activation. CONCLUSION: This study suggests that miR-216a protects against HRMECs injury in DR by suppressing the NOS2/JAK/STAT axis.


Assuntos
Retinopatia Diabética/patologia , Células Endoteliais/patologia , Janus Quinases/metabolismo , MicroRNAs/metabolismo , Microvasos/patologia , Óxido Nítrico Sintase Tipo II/metabolismo , Retina/patologia , Fatores de Transcrição STAT/metabolismo , Animais , Sobrevivência Celular/efeitos dos fármacos , Citoproteção/efeitos dos fármacos , Regulação para Baixo/genética , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Glucose/toxicidade , Humanos , Masculino , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos
12.
Rev Mal Respir ; 37(3): 193-196, 2020 Mar.
Artigo em Francês | MEDLINE | ID: mdl-32146057

RESUMO

In addition to its role in erythropoiesis, erythropoietin (Epo) plays a role in tissue protection, which includes cardioprotective, nephroprotective and neuroprotective effects. The presence of Epo and its receptor (Epo-R) in pulmonary tissue also suggests a cytoprotective effect of Epo in the lung. Our project aims to document this role in a murine model under-expressing Epo. The obtained results will lead to a better understanding of the cytoprotective effects of Epo and will also give an appreciation of its beneficial effects in cases of lung injury.


Assuntos
Lesão Pulmonar Aguda/patologia , Citoproteção , Eritropoetina/farmacologia , Eritropoetina/fisiologia , Rim , Animais , Citoproteção/efeitos dos fármacos , Citoproteção/genética , Modelos Animais de Doenças , Eritropoetina/genética , Hematopoese/efeitos dos fármacos , Hematopoese/genética , Humanos , Rim/efeitos dos fármacos , Rim/patologia , Pulmão/efeitos dos fármacos , Pulmão/patologia , Pulmão/fisiologia , Camundongos
13.
Arch Med Res ; 51(1): 82-94, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-32113058

RESUMO

BACKGROUND AND AIM: Possible Hepato-protective effects of L-carnitine have been reported in previous studies. Present study was conducted to systematically review the efficacy of L-carnitine supplementation on liver enzymes. METHODS: The following databases were searched up to December 2018: PubMed, Scopus, ISI Web of Science, and the Cochrane library. Only randomized controlled trials (RCTs) evaluating the effects of L-carnitine supplementation on liver enzymes including alanine aminotransferase (ALT), aspartate aminotransferase (AST) and gamma-glutamyl transferase (GGT) were included. Pooled effect size measured using random effect model (Dersimonian-Liard). RESULTS: A total of 16 studies (including 1025 participants) were included in the present meta-analysis. Pooled analysis indicated that L-carnitine supplementation significantly decreased ALT (weighted mean difference (WMD): -10.729 IU/L, 95% CI: -13.787, -7.672, p <0.001; I2 = 95.9%), AST (WMD: -7.149 IU/L, 95% CI: -9.202, -5.096, p <0.001; I2 = 93.5%) and GGT (WMD: -7.395: IU/L, 95% CI: -9.171, -5.619, p <0.001; I2 = 80.1%). Subgroup analysis revealed that effect of L-carnitine supplementation on liver enzymes was not significant in normal weight and healthy subjects. Baseline BMI and health status were the potential source of heterogeneity. CONCLUSION: L-carnitine supplementation showed beneficial hepato-protective effects on circulating liver enzymes.


Assuntos
Carnitina/farmacologia , Fígado/efeitos dos fármacos , Fígado/enzimologia , Ensaios Clínicos Controlados Aleatórios como Assunto/estatística & dados numéricos , Alanina Transaminase/efeitos dos fármacos , Alanina Transaminase/metabolismo , Aspartato Aminotransferases/efeitos dos fármacos , Aspartato Aminotransferases/metabolismo , Carnitina/administração & dosagem , Citoproteção/efeitos dos fármacos , Suplementos Nutricionais , Humanos , Fígado/metabolismo , Substâncias Protetoras/administração & dosagem , Substâncias Protetoras/farmacologia , gama-Glutamiltransferase/efeitos dos fármacos , gama-Glutamiltransferase/metabolismo
14.
Oxid Med Cell Longev ; 2020: 8351342, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32190178

RESUMO

Endothelial cell damage caused by oxidative stress is widely considered to be a triggering event in atherosclerosis (AS). However, the specific effect elicited by autophagy in endothelial cells undergoing oxidative stress remains controversial, especially during end-stage autophagy. The inhibition of end-stage autophagy has been reported to increase cell pyroptosis and contribute to endothelial damage. Several studies have shown that microRNA-103 is involved in end-stage autophagy; however, its specific mechanism of action is not yet characterized. In this study, we addressed the regulatory role of miR-103 in autophagy during oxidative stress of endothelial cells. Hydrogen peroxide (H2O2) treatment was used as an in vitro model of oxidative stress. MTS and ROS levels were measured to evaluate cell activity. qRT-PCR was used to detect the expression of miR-103. Autophagy was examined using western blot, immunofluorescence staining, and electron microscopy, while western blot analysis detected pyroptosis-related proteins. Results show that miR-103 expression decreased under oxidative stress. Further, miR-103 repressed transcription of Bcl-2/adenovirus E1B 19 kDa interacting protein (BNIP3). The oxidative stress caused by H2O2 caused cell damage from 2 hours (P < 0.05) and increased the level of intracellular reactive oxygen species (P < 0.05); at the same time, the damage could be further aggravated by the stimulation of bafA1 (P < 0.05). Under the stimulation of H2O2, the expression of miR-103 decreased (P < 0.05). However, high expression of miR-103 could reduce the accumulation of LC3II and P62 (P < 0.05) by inhibiting the downstream target gene Bcl-2/adenovirus E1B 19 kDa interacting protein (BNIP3), thus reducing the occurrence of cell pyroptosis (P < 0.05). This process could be blocked by end-stage autophagy inhibitor bafA1 (P < 0.05), which further indicated that miR-103 affected cell injury by autophagy. On the contrary, the low expression of miR-103 promoted the accumulation of autophagy protein and increased the occurrence of pyroptosis (P < 0.05). In conclusion, inhibition of miR-103 restrained end-stage of autophagy by regulating BNIP3, thus changing the occurrence of cell pyroptosis.


Assuntos
Autofagia/genética , Vasos Coronários/patologia , Células Endoteliais/patologia , Peróxido de Hidrogênio/toxicidade , Proteínas de Membrana/metabolismo , MicroRNAs/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Proteínas Proto-Oncogênicas/metabolismo , Piroptose/genética , Autofagia/efeitos dos fármacos , Citoproteção/efeitos dos fármacos , Citoproteção/genética , Regulação para Baixo/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Humanos , MicroRNAs/genética , Estresse Oxidativo/genética , Piroptose/efeitos dos fármacos
15.
Oxid Med Cell Longev ; 2020: 9349762, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32184919

RESUMO

Although endogenous nucleus pulposus-derived mesenchymal stem cell- (NPMSC-) based regenerative medicine has provided promising repair strategy for intervertebral disc (IVD) degeneration, the hostile microenvironments in IVD, including oxidative stress, can negatively affect the survival and function of the NPMSCs and severely hinder the endogenous repair process. Therefore, it is of great importance to reveal the mechanisms of the endogenous repair failure caused by the adverse microenvironments in IVD. The aim of this study was to investigate the effect of oxidative stress on the rat NPMSCs and its underlying mechanism. Our results demonstrated that oxidative stress inhibited cell viability, induced apoptosis, and increased the production of reactive oxygen species (ROS) in NPMSCs. In addition, the results showed that the expression level of heme oxygenase-1 (HO-1) increased at an early stage but decreased at a late stage when NPMSCs were exposed to oxidative stress, and the oxidative damages of NPMSCs could be partially reversed by promoting the expression of HO-1. Further mechanistic analysis indicated that the protective effect of HO-1 against oxidative damage in NPMSCs was mediated by the activation of autophagy. Taken together, our study revealed that oxidative stress could inhibit cell viability, induce apoptosis, and increase ROS production in NPMSCs, and HO-1-mediated autophagy might act as a protective response to the oxidative damage. These findings might enhance our understanding on the mechanism of the endogenous repair failure during IVD degeneration and provide novel research direction for the endogenous repair of IVD degeneration.


Assuntos
Autofagia , Citoproteção , Heme Oxigenase-1/metabolismo , Células-Tronco Mesenquimais/patologia , Núcleo Pulposo/patologia , Estresse Oxidativo , Animais , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Citoproteção/efeitos dos fármacos , Peróxido de Hidrogênio/toxicidade , Masculino , Células-Tronco Mesenquimais/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Ratos Sprague-Dawley
16.
Biochem Biophys Res Commun ; 526(1): 206-212, 2020 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-32201079

RESUMO

Gadolinium-based contrast agents (GBCAs) are widely used in clinical magnetic resonance imaging (MRI). Free gadolinium ions (Gd3+) released from GBCAs potentially increase the risk of GBCA-related toxicity. However, the cellular responses to Gd3+ and the underlying mechanisms responsible for protection against Gd3+ remain poorly understood. Recently, autophagy has been considered a cell survival mechanism against various toxic metals. Here, we investigated the relationship between Gd3+ and autophagy, as well as the effect of autophagy inhibition on the survival of cells exposed to Gd3+. We found that the increased expression of microtubule-associated protein 1 light chain 3 (LC3)-II, a marker protein of autophagy, in Gd3+-exposed human embryonic kidney 293 (HEK293) cells. Moreover, we found a greater accumulation of LC3-II after exposure to an autophagy inhibitor, chloroquine (CQ), combined with Gd3+ than that after exposure to CQ alone, suggesting that Gd3+ activated autophagy in HEK293 cells. Furthermore, we found that Gd3+ reduced cell viability, which was more pronounced after CQ treatment. Our findings indicated that autophagy exerted a cytoprotective effect against Gd3+ toxicity, suggesting a potential link between autophagy and GBCA-associated adverse events.


Assuntos
Autofagia/efeitos dos fármacos , Gadolínio/toxicidade , Animais , Morte Celular/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Cloroquina/farmacologia , Citoproteção/efeitos dos fármacos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Humanos , Íons , Camundongos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Fator de Transcrição CHOP/genética , Fator de Transcrição CHOP/metabolismo
17.
Nat Commun ; 11(1): 1270, 2020 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-32152280

RESUMO

Prolonged cell survival occurs through the expression of specific protein isoforms generated by alternate splicing of mRNA precursors in cancer cells. How alternate splicing regulates tumor development and resistance to targeted therapies in cancer remain poorly understood. Here we show that RNF113A, whose loss-of-function causes the X-linked trichothiodystrophy, is overexpressed in lung cancer and protects from Cisplatin-dependent cell death. RNF113A is a RNA-binding protein which regulates the splicing of multiple candidates involved in cell survival. RNF113A deficiency triggers cell death upon DNA damage through multiple mechanisms, including apoptosis via the destabilization of the prosurvival protein MCL-1, ferroptosis due to enhanced SAT1 expression, and increased production of ROS due to altered Noxa1 expression. RNF113A deficiency circumvents the resistance to Cisplatin and to BCL-2 inhibitors through the destabilization of MCL-1, which thus defines spliceosome inhibitors as a therapeutic approach to treat tumors showing acquired resistance to specific drugs due to MCL-1 stabilization.


Assuntos
Proteínas de Ligação a DNA/genética , Genes Ligados ao Cromossomo X , Spliceossomos/metabolismo , Síndromes de Tricotiodistrofia/genética , Células A549 , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/patologia , Processamento Alternativo/genética , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Sobrevivência Celular/genética , Cisplatino/farmacologia , Citoproteção/efeitos dos fármacos , Dano ao DNA/genética , Proteína Quinase Ativada por DNA/metabolismo , Proteínas de Ligação a DNA/deficiência , Proteínas de Ligação a DNA/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Íntrons/genética , Camundongos Endogâmicos NOD , Camundongos SCID , Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , Proteínas de Neoplasias/metabolismo , Fosforilação/efeitos dos fármacos , Estabilidade Proteica/efeitos dos fármacos , Subunidades Proteicas/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Espécies Reativas de Oxigênio/metabolismo
18.
PLoS One ; 15(3): e0219275, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32163417

RESUMO

Pathogenic bacteria often damage tissues by secreting toxins that form pores in cell membranes, and the most common pore-forming toxins are cholesterol-dependent cytolysins. During bacterial infections, glutamine becomes a conditionally essential amino acid, and glutamine is an important nutrient for immune cells. However, the role of glutamine in protecting tissue cells against pore-forming toxins is unclear. Here we tested the hypothesis that glutamine supports the protection of tissue cells against the damage caused by cholesterol-dependent cytolysins. Stromal and epithelial cells were sensitive to damage by the cholesterol-dependent cytolysins, pyolysin and streptolysin O, as determined by leakage of potassium and lactate dehydrogenase from cells, and reduced cell viability. However, glutamine deprivation increased the leakage of lactate dehydrogenase and reduced the viability of cells challenged with cholesterol-dependent cytolysins. Without glutamine, stromal cells challenged with pyolysin leaked lactate dehydrogenase (control vs. pyolysin, 2.6 ± 0.6 vs. 34.4 ± 4.5 AU, n = 12), which was more than three-fold the leakage from cells supplied with 2 mM glutamine (control vs. pyolysin, 2.2 ± 0.3 vs. 9.4 ± 1.0 AU). Glutamine cytoprotection did not depend on glutaminolysis, replenishing the Krebs cycle via succinate, changes in cellular cholesterol, or regulators of cell metabolism (AMPK and mTOR). In conclusion, although the mechanism remains elusive, we found that glutamine supports the protection of tissue cells against the damage caused by cholesterol-dependent cytolysins from pathogenic bacteria.


Assuntos
Colesterol/metabolismo , Citoproteção/efeitos dos fármacos , Citotoxinas/toxicidade , Glutamina/farmacologia , Animais , Proteínas de Bactérias/toxicidade , Toxinas Bacterianas/toxicidade , Bovinos , Células HeLa , Proteínas Hemolisinas/toxicidade , Humanos , L-Lactato Desidrogenase/metabolismo , Estreptolisinas/toxicidade , Células Estromais/efeitos dos fármacos
19.
Biochem Biophys Res Commun ; 524(3): 736-743, 2020 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-32035614

RESUMO

Deferasirox (DFX) is an iron chelator approved for the treatment of iron overload diseases. However, the role of DFX in oxidative stress-induced cell apoptosis and the exact molecular mechanisms underlying these processes remain poorly understood and require further investigation. In this study, we found that DFX rendered resistant to H2O2-induced apoptosis in HEK293T cells, reduced the intracellular levels of the labile iron pool (LIP) and oxidative stress induced by H2O2. Furthermore, DFX inhibited the ubiquitination and degradation of the cyclin-dependent kinase inhibitor p21WAF1/CIP1 (p21) via modulation of the interaction of p21 with SCF-Skp2. DFX also showed the inhibition effect on the activation of c-Jun N-terminal kinase (JNK), pro-caspase-3 and related mitochondrial apoptosis pathway induced by H2O2. These results provide novel insights into the molecular mechanism underpinning iron-mediated oxidative stress and apoptosis, and they may represent a promising target for therapeutic interventions in related pathological conditions.


Assuntos
Apoptose/efeitos dos fármacos , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Citoproteção/efeitos dos fármacos , Deferasirox/farmacologia , Proteólise/efeitos dos fármacos , Ubiquitinação/efeitos dos fármacos , Caspase 3/metabolismo , Células HEK293 , Humanos , Peróxido de Hidrogênio , Ferro/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Ubiquitina/metabolismo , Regulação para Cima/efeitos dos fármacos
20.
Biochem Biophys Res Commun ; 524(3): 575-581, 2020 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-32019675

RESUMO

Inhibiting the production of reactive oxygen species (ROS) in alveolar epithelial cells (AECs) under oxidative distress becomes a new therapeutic strategy for acute respiratory distress syndrome (ARDS). Herein in the present study, we investigated effects of Nox2, the catalytic subunit of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase type 2, on LPS-induced epithelium injury in ARDS mice and in human alveolar epithelial A549 cells. Severe lung injury, disruption of alveolar-capillary barrier with the loss of zonula occluden (ZO)-1 and up-regulated expression of Nox2 in AECs were exhibited in ARDS mice. In vitro, LPS induced decreased cell viability coupled with activated Nox2, high level of ROS, and destroyed ZO-1 distribution. Moreover, VAS2870 proved to inhibit Nox2 expression, reduce ROS generation, restore epithelium barrier integrity, and preserve cell viability in LPS-induced A549 cells. These data demonstrate that Nox2/ROS/ZO-1 axis is of great importance in AECs damage induced by LPS, and the utilization of VAS2870 to inhibit this pathway might lighten LPS-induced ARDS.


Assuntos
Células Epiteliais Alveolares/metabolismo , Citoproteção/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , NADPH Oxidase 2/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Junções Íntimas/metabolismo , Células A549 , Células Epiteliais Alveolares/efeitos dos fármacos , Células Epiteliais Alveolares/patologia , Animais , Benzoxazóis , Capilares/efeitos dos fármacos , Capilares/metabolismo , Ativação Enzimática/efeitos dos fármacos , Epitélio/efeitos dos fármacos , Epitélio/metabolismo , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Camundongos Endogâmicos BALB C , /metabolismo , Junções Íntimas/efeitos dos fármacos , Triazóis , Regulação para Cima/efeitos dos fármacos , Proteína da Zônula de Oclusão-1/metabolismo
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