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1.
Chem Biol Interact ; 324: 109086, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32275923

RESUMO

Oxidative stress-induced apoptosis of retinal ganglion cells (RGCs) contributes to the development and progression of glaucoma. Sestrin2 (Sesn2), a stress-inducible protein, has a potent antioxidant capacity that can provide cytoprotection against various noxious stimuli. However, whether Sesn2 is involved in protecting RGCs from oxidative stress remains unexplored. The purpose of this study was to evaluate the role of Sesn2 in regulating hydrogen peroxide (H2O2)-induced oxidative stress of RGCs. Here, we showed that Sesn2 expression was induced in RGCs following H2O2 exposure. Sesn2 depletion markedly exacerbated H2O2-induced apoptosis and reactive oxygen species (ROS) generation in RGCs. Notably, upregulation of Sesn2 significantly decreased H2O2-induced apoptosis and ROS generation. Moreover, Sesn2 overexpression increased the nuclear translocation of nuclear factor erythroid-derived 2-like 2 (Nrf2), elevated Nrf2/antioxidant response element (ARE)-mediated transcriptional activity and upregulated the expression of Nrf2 target genes in H2O2-stimulated RGCs. Interestingly, we found that Sesn2 promoted Nrf2/ARE activation through downregulation of kelch-like ECH-associated protein 1 (Keap1). Restoration of Keap1 or inhibition of Nrf2 significantly reversed the Sesn2-mediated protective effect in H2O2-stimulated RGCs. In conclusion, these results elucidated that Sesn2 confers a protective effect in RGCs against H2O2-induced oxidative stress by reinforcing Nrf2/ARE activation via downregulation of Keap1. Our study suggests that the Sesn2/Keap1/Nrf2 axis may play an important role in retinal degeneration in glaucoma.


Assuntos
Apoptose/fisiologia , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Proteínas Nucleares/metabolismo , Estresse Oxidativo/fisiologia , Células Ganglionares da Retina/metabolismo , Animais , Elementos de Resposta Antioxidante/fisiologia , Apoptose/efeitos dos fármacos , Regulação para Baixo , Peróxido de Hidrogênio/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Ratos , Células Ganglionares da Retina/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Regulação para Cima
2.
PLoS Biol ; 18(2): e3000620, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32053600

RESUMO

Primary cilia are lost during cancer development, but the mechanism regulating cilia degeneration is not determined. While transcription factor nuclear factor-erythroid 2-like 2 (NRF2) protects cells from oxidative, proteotoxic, and metabolic stress in normal cells, hyperactivation of NRF2 is oncogenic, although the detailed molecular mechanisms by which uncontrolled NRF2 activation promotes cancer progression remain unclear. Here, we report that NRF2 suppresses hedgehog (Hh) signaling through Patched 1 (PTCH1) and primary ciliogenesis via p62/sequestosome 1 (SQSTM1). PTCH1, a negative regulator of Hh signaling, is an NRF2 target gene, and as such, hyperactivation of NRF2 impairs Hh signaling. NRF2 also suppresses primary cilia formation through p62-dependent inclusion body formation and blockage of Bardet-Biedl syndrome 4 (BBS4) entrance into cilia. Simultaneous ablation of PTCH1 and p62 completely abolishes NRF2-mediated inhibition of both primary ciliogenesis and Hh signaling. Our findings reveal a previously unidentified role of NRF2 in controlling a cellular organelle, the primary cilium, and its associated Hh signaling pathway and also uncover a mechanism by which NRF2 hyperactivation promotes tumor progression via primary cilia degeneration and aberrant Hh signaling. A better understanding of the crosstalk between NRF2 and primary cilia/Hh signaling could not only open new avenues for cancer therapeutic discovery but could also have significant implications regarding pathologies other than cancer, including developmental disorders, in which improper primary ciliogenesis and Hh signaling play a major role.


Assuntos
Cílios/fisiologia , Proteínas Hedgehog/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Animais , Elementos de Resposta Antioxidante , Células Cultivadas , Cílios/metabolismo , Expressão Gênica , Técnicas de Inativação de Genes , Proteínas Hedgehog/antagonistas & inibidores , Humanos , Corpos de Inclusão/metabolismo , Camundongos , Proteínas Associadas aos Microtúbulos/metabolismo , Fator 2 Relacionado a NF-E2/genética , Receptor Patched-1/genética , Receptor Patched-1/metabolismo , Proteína Sequestossoma-1/genética , Proteína Sequestossoma-1/metabolismo , Transdução de Sinais
3.
Life Sci ; 242: 117240, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31891722

RESUMO

Lycium barbarum polysaccharides (LBP) are derived from Wolfberry and have antioxidant activities. This study aimed to evaluate the efficacy of LBP for kidney injury in a rat model of sepsis. Male rats were divided randomly to control group (Con), LPS group (LPS), ulinastatin group (ULI), low dose LBP group (LBP-1), middle dose LBP group (LBP-2) and high dose LBP group (LBP-3). After intraperitoneal injection of LPS (5 mg/kg) to make sepsis model (LPS group), 10,000 U/kg ulinastatin were given in ULI group, and 200, 400 and 800 mg/kg LBP was given in LBP-1, -2, -3 group, respectively. Serum IL-1ß, IL-6, IL-8, TNF-α and NF-κB levels were measured by ELISA. Nrf2, Keap1, NF-κB, HO-1 and NQO1 expression levels were detected by PCR and Western blot analysis. We found that LBP decreased the levels of NF-κB and pro-inflammatory cytokines while attenuated kidney injury. In addition, LBP regulated Keap1-Nrf2/ARE signaling pathway in the kidney. In conclusion, LBP attenuates inflammation injury in the kidney via possible regulation of Keap1-Nrf2/ARE signaling.


Assuntos
Lesão Renal Aguda/prevenção & controle , Elementos de Resposta Antioxidante/efeitos dos fármacos , Medicamentos de Ervas Chinesas/farmacologia , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Sepse/complicações , Transdução de Sinais/efeitos dos fármacos , Animais , Western Blotting , Citocinas/metabolismo , Modelos Animais de Doenças , Masculino , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase em Tempo Real
4.
Arch Oral Biol ; 110: 104602, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31734544

RESUMO

OBJECTIVE: Oxidative stress, which is defined as an imbalance between pro-oxidant and antioxidant systems, has been implicated in the development and/or progression of several inflammatory diseases, including periodontal disease. The reactive oxygen species (ROS) are the primary inducers of oxidative stress. In the induction of cytoprotective enzymes, the nuclear factor erythroid 2-related factor 2 (Nrf2)/antioxidant response element (ARE) signaling in antioxidant systems takes a main role. Notably, 10-oxo-trans-11-octadecenoic acid (KetoC), known as a bioactive metabolite generated by intestinal microorganisms, has been reported to have beneficial effects on several biological responses. Therefore, we investigated the antioxidant effect of KetoC on gingival epithelial cells (GECs) in this present study. METHODS: An SV40-T antigen-transformed human gingival epithelial cell line (Epi4) was used for experiments. The alteration of anti-oxidative stress related genes was analyzed by qPCR. The cellular ROS levels were evaluated by flow cytometry. To explore its molecular mechanisms, ARE promotor activity was analyzed by luciferase assay; the involvement of mitogen-activated protein kinase (MAPK) and G protein-coupled receptor 120 (GPR120) were evaluated by Western blotting and luciferase assay, respectively. RESULTS: KetoC significantly increased the expression of antioxidant-related genes in GECs. The level of ROS was significantly inhibited by the pretreatment of KetoC. Extracellular signal-regulated kinase (ERK) phosphorylation by KetoC promoted both the nuclear translocation of Nrf2 and its binding to the ARE in GECs. Further, GPR120 regulated the activation of KetoC induced-Nrf2-ARE signaling. CONCLUSION: KetoC exerts a protective function against the oxidative stress in GECs through GPR120-dependent ERK-Nrf2-ARE signaling.


Assuntos
Elementos de Resposta Antioxidante , Gengiva , Ácidos Linoleicos , Fator 2 Relacionado a NF-E2 , Estresse Oxidativo , Transdução de Sinais , Antioxidantes , Células Epiteliais , Gengiva/citologia , Gengiva/metabolismo , Humanos , Ácidos Linoleicos/farmacologia , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Espécies Reativas de Oxigênio
5.
Chem Biol Interact ; 316: 108922, 2020 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-31837296

RESUMO

Homeodomain interacting protein kinase-2 (HIPK2) has emerged as a crucial stress-responsive kinase that plays a critical role in regulating cell survival and apoptosis. However, whether HIPK2 participates in regulating cardiomyocyte survival during myocardial ischemia/reperfusion injury remains unclear. Here, we investigated the regulatory effect of HIPK2 on hypoxia/reoxygenation (H/R)-induced cardiomyocyte injury and its potential underlying molecular mechanism. We found that HIPK2 expression was induced in response to H/R exposure. HIPK2 depletion by small interfering RNA (siRNA)-mediated gene silencing significantly decreased the viability and exacerbated H/R-induced apoptosis and reactive oxygen species (ROS) production in cardiomyocytes. Comparatively, HIPK2 overexpression effectively rescued H/R-impaired viability and repressed H/R-induced apoptosis and ROS production in cardiomyocytes. HIPK2 overexpression significantly increased the nuclear expression of nuclear factor (erythroid-derived 2)-like 2 (Nrf2) and enhanced Nrf2-mediated transcriptional activity. Moreover, HIPK2 overexpression significantly increased the transcription of Nrf2/ARE target genes. Additionally, Nrf2 inhibition partially reversed the HIPK2-mediated protective effect. Overall, these results demonstrate that HIPK2 overexpression protects cardiomyocytes from H/R-induced injury by enhancing Nrf2/ARE antioxidant signaling, data that suggest HIPK2 is a potential target for cardioprotection.


Assuntos
Apoptose/efeitos dos fármacos , Hipóxia Celular , Estresse Oxidativo/efeitos dos fármacos , Oxigênio/farmacologia , Proteínas Serina-Treonina Quinases/metabolismo , Transdução de Sinais/efeitos dos fármacos , Animais , Elementos de Resposta Antioxidante/genética , Células Cultivadas , Camundongos , Miócitos Cardíacos/citologia , Miócitos Cardíacos/metabolismo , Fator 2 Relacionado a NF-E2/antagonistas & inibidores , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/genética , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Espécies Reativas de Oxigênio/metabolismo
6.
Chem Biol Interact ; 314: 108848, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31610156

RESUMO

Cardiomyocyte injury induced by acute myocardial infarction contributes to myocardial dysfunction. Accumulating evidence has demonstrated that pleckstrin homology domain leucine-rich repeat protein phosphatase 2 (PHLPP2) is a cytoprotective protein that protects against various adverse injuries. However, whether PHLPP2 participates in regulating myocardial-infarction-induced cardiomyocyte injury remains unknown. In the present study, we aimed to investigate the biological role and molecular mechanism of PHLPP2 in regulating hypoxia-induced cardiomyocyte injury. Cardiomyocytes were cultured in an anaerobic chamber for 24 h to induce hypoxic injury in vitro. The expression of PHLPP2 was determined by real-time quantitative PCR and Western blot analysis. Cell viability was measured by MTT assay. Cell apoptosis was assessed by TUNEL and caspase-3 activity assays. Intracellular reactive oxygen species (ROS) levels were measured by DCFH-DA probe. PHLPP2 expression was highly upregulated in hypoxia-injured cardiomyocytes. Inhibition of PHLPP2 by small interfering RNA (siRNA)-mediated gene silencing significantly improved the viability of hypoxia-injured cardiomyocytes and attenuated hypoxia-induced apoptosis and ROS production. In contrast, PHLPP2 overexpression exacerbated hypoxia-induced apoptosis and ROS production in cardiomyocytes. Mechanism research revealed that PHLPP2 silencing increased the phosphorylation of glycogen synthase kinase (GSK)-3ß and promoted the nuclear translocation of nuclear factor (erythroid-derived 2)-like 2 (Nrf2). In addition, PHLPP2 inhibition promoted Nrf2/antioxidant response element (ARE) transcriptional activity. However, Nrf2 silencing markedly reversed PHLPP2-inhibition-mediated cardioprotection, while GSK-3ß inhibition partially blocked the PHLPP2-overexpression-induced adverse effect. Taken together, these findings demonstrate that PHLPP2 inhibition alleviates hypoxia-induced cardiomyocyte injury by reinforcing Nrf2/ARE antioxidant signaling via inactivating GSK-3ß, a pathway that highlights the importance of the PHLPP2/GSK-3ß/Nrf2/ARE signaling axis in regulation of cardiomyocyte injury. Our study suggests a potential relevance for PHLPP2 in acute myocardial infarction, and this protein may serve as a promising target for cardioprotection.


Assuntos
Elementos de Resposta Antioxidante/genética , Hipóxia Celular , Fator 2 Relacionado a NF-E2/metabolismo , Fosfoproteínas Fosfatases/metabolismo , Animais , Apoptose/efeitos dos fármacos , Sobrevivência Celular , Regulação para Baixo , Glicogênio Sintase Quinase 3 beta/antagonistas & inibidores , Glicogênio Sintase Quinase 3 beta/metabolismo , Camundongos , Miócitos Cardíacos/citologia , Miócitos Cardíacos/metabolismo , Fator 2 Relacionado a NF-E2/antagonistas & inibidores , Fator 2 Relacionado a NF-E2/genética , Fosfoproteínas Fosfatases/antagonistas & inibidores , Fosfoproteínas Fosfatases/genética , Fosforilação , Pirimidinas/farmacologia , Pirróis/farmacologia , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos
7.
IET Syst Biol ; 13(5): 243-250, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31538958

RESUMO

In humans, oxidative stress is involved in the development of diabetes, cancer, hypertension, Alzheimers' disease, and heart failure. One of the mechanisms in the cellular defence against oxidative stress is the activation of the Nrf2-antioxidant response element (ARE) signalling pathway. Computation of activity, efficacy, and potency score of ARE signalling pathway and to propose a multi-level prediction scheme for the same is the main aim of the study as it contributes in a big amount to the improvement of oxidative stress in humans. Applying the process of knowledge discovery from data, required knowledge is gathered and then machine learning techniques are applied to propose a multi-level scheme. The validation of the proposed scheme is done using the K-fold cross-validation method and an accuracy of 90% is achieved for prediction of activity score for ARE molecules which determine their power to refine oxidative stress.


Assuntos
Biologia Computacional/métodos , Estresse Oxidativo/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Elementos de Resposta Antioxidante/efeitos dos fármacos , Modelos Estatísticos , Curva ROC
8.
Pestic Biochem Physiol ; 159: 118-126, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31400773

RESUMO

In the plant-insect arms race, plants synthesize toxic compounds to defend against herbivorous insects, whereas insects employ cytochrome P450 monooxygenases (P450s) to detoxify these phytotoxins. As ubiquitous environmental contaminants, heavy metals can be easily absorbed by plants and further accumulated in herbivorous insects through the food chains, resulting in tangible consequences for plant-insect interactions. However, whether heavy metals can influence P450 activities and thereby cause further effects on larval tolerance to phytotoxins remains unknown. In this study, we shown that prior exposure to copper (Cu) enhanced larval tolerance to xanthotoxin in Spodoptera litura, a major polyphagous pest of agriculture. P450 activities were induced in larvae exposed to Cu or xanthotoxin, and a midgut specific expressed P450 gene, CYP6B50 was cross-induced after exposure to these two toxic xenobiotics. Knocking down CYP6B50 by RNA interference (RNAi) rendered the larvae more sensitive to xanthotoxin. As defense against oxidative stress following metal exposure has been demonstrated to affect insecticide resistance, the reactive oxygen species (ROS) generation and antioxidant enzyme activities were assessed. Cu exposure caused the accumulation of hydrogen peroxide (H2O2) and enhanced the activities of superoxide dismutase (SOD) and peroxidase (POD) in larval midgut. In addition, two antioxidant response elements (AREs) were identified from the CYP6B50 promoter, indicating that Cu-induced CYP6B50 expression may be related to the ROS burst. Application of ROS scavenger N-acetylcysteine (NAC) effectively suppressed CYP6B50 expression, inhibited P450 activities and impaired larval tolerance to xanthotoxin that had been induced by Cu. These results indicate that the increase in CYP6B50 expression regulated by Cu-induced H2O2 generation contributed to the enhancement of larval tolerance to xanthotoxin in S. litura. Ingestion of heavy metals from their host plants can inadvertently boost the counter-defense system of herbivorous insects to protect themselves against plant defensive toxins.


Assuntos
Cobre/farmacologia , Peróxido de Hidrogênio/metabolismo , Metoxaleno/farmacologia , Spodoptera/efeitos dos fármacos , Spodoptera/metabolismo , Animais , Elementos de Resposta Antioxidante/genética , Elementos de Resposta Antioxidante/fisiologia , Sistema Enzimático do Citocromo P-450/metabolismo , Peroxidase/genética , Peroxidase/metabolismo , Interferência de RNA , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo
9.
Mol Med Rep ; 20(4): 3095-3102, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31432116

RESUMO

Berberine (BBR) is an isoquinoline alkaloid, reported to have multiple pharmacological functions. However, its effects against CCl4­induced oxidative damage remain poorly studied. Therefore, the present study investigated the protective action of BBR, and its antioxidant mechanisms, against CCl4­induced liver injury in rats. A total of 48 rats were randomly arranged into six groups: Control; model; positive control (PC); BBR low­dose (BL); BBR middle­dose (BM); and BBR high­dose (BH). The BL, BM and BH animals received BBR (5, 10 and 15 mg/kg by weight, respectively) orally for 7 consecutive days. Rats in the PC group were given silymarin (150 mg/kg), and the control and model groups were administered distilled water orally. At the end of the experiment, blood samples and livers were collected. To measure the liver biochemical indices, the reactive oxygen species (ROS) generation and the expression levels of related genes and protein, the following methods were used: An automatic biochemical analyzer; flow cytometry; spectrophotometry; reverse transcription­quantitative PCR; western blotting; and hematoxylin and eosin staining. The results revealed that BBR significantly decreased the serum levels of alanine transaminase, aspartate transaminase and alkaline phosphatase, and increased those of glutathione and superoxide dismutase, but decreased malondialdehyde activity in hepatic tissue, and significantly decreased the reactive oxygen species level in hepatocytes. In hepatic tissue, the expressions of nuclear factor erythroid 2­related factor 2 (Nrf2), kelch­like ECH­associated protein 1 (Keap-1), NAD(P)H quinone dehydrogenase 1 (NQO-1), heme oxygenase 1 (HO­1), Bcl­2 and Bcl­xL mRNA, and HO­1 protein were elevated, and the expression of p53 mRNA was decreased, particularly in the BH group (15 mg/kg). In conclusion, BBR exerts a protective action against CCl4­induced acute liver injury in rats via effectively regulating the expression of Nrf2­Keap1­antioxidant responsive element­related genes and proteins, and inhibiting p53 pathway­mediated hepatocyte apoptosis.


Assuntos
Elementos de Resposta Antioxidante , Berberina/farmacologia , Tetracloreto de Carbono/toxicidade , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Regulação da Expressão Gênica/efeitos dos fármacos , Proteína 1 Associada a ECH Semelhante a Kelch/biossíntese , Fator 2 Relacionado a NF-E2/biossíntese , Transdução de Sinais/efeitos dos fármacos , Proteína Supressora de Tumor p53/biossíntese , Animais , Apoptose/efeitos dos fármacos , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/patologia , Hepatócitos/metabolismo , Hepatócitos/patologia , Fígado/metabolismo , Fígado/patologia , Masculino , Ratos , Ratos Sprague-Dawley
10.
J Agric Food Chem ; 67(29): 8227-8234, 2019 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-31299148

RESUMO

The mechanisms underlying neurodegenerative diseases are not fully understood yet. However, an increasing amount of evidence has suggested that these disorders are related to oxidative stress. We reported herein that lipoamide (LM), a neutral amide derivative of lipoic acid (LA), could resist oxidative stress-mediated neuronal cell damage. LM is more potent than LA in alleviating hydrogen peroxide- or 6-hydroxydopamine-induced PC12 cell injury. Our results reveal that LM promotes the nuclear accumulation of NFE2-related factor 2 (Nrf2), following with the activation of expression of Nrf2-governed antioxidant and detoxifying enzymes. Notably, silencing Nrf2 gene annuls the protection of LM, which demonstrates that Nrf2 is engaged in this cytoprotection. Our findings suggest that LM might be used as a potential therapeutic candidate for oxidative stress-related neurological disorders.


Assuntos
Fator 2 Relacionado a NF-E2/metabolismo , Fármacos Neuroprotetores/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Ácido Tióctico/análogos & derivados , Animais , Elementos de Resposta Antioxidante/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/genética , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Células PC12 , Ratos , Transdução de Sinais/efeitos dos fármacos , Ácido Tióctico/farmacologia
11.
Oxid Med Cell Longev ; 2019: 7283683, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31308876

RESUMO

Antioxidative stress provides a cardioprotective effect during myocardial ischemia/reperfusion (I/R). Previous research has demonstrated that the blockade of transient receptor potential vanilloid 4 (TRPV4) attenuates myocardial I/R injury. However, the underlying mechanism remains unclear. The current study is aimed at investigating the antioxidative activity of TRPV4 inhibition and elucidating the underlying mechanisms in vitro and ex vivo. We found that the inhibiting TRPV4 by the selective TRPV4 blocker HC-067047 or specific TRPV4-siRNA significantly reduces reactive oxygen species (ROS) and methane dicarboxylic aldehyde (MDA) levels in H9C2 cells exposed to hypoxia/reoxygenation (H/R). Meanwhile, the activity of antioxidative enzymes, particularly superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), is enhanced. Furthermore, after H/R, HC-067047 treatment increases the expression of P-Akt and the translocation of nuclear factor E2-related factor 2 (Nrf2) and related antioxidant response element (ARE) mainly including SOD, GSH-Px, and catalase (CAT). LY294002, an Akt inhibitor, suppresses HC-067047 and specific TRPV4-siRNA-induced Nrf2 expression and its nuclear accumulation. Nrf2 siRNA attenuates HC-067047 and specific TRPV4-siRNA-induced ARE expression. In addition, treatment with LY294002 or Nrf2 siRNA significantly attenuates the antioxidant and anti-injury effects of HC-067047 in vitro. Finally, in experiments on isolated rat hearts, we confirmed the antioxidative stress roles of TRPV4 inhibition during myocardial I/R and the application of exogenous H2O2. In conclusion, the inhibition of TRPV4 exerts cardioprotective effects through enhancing antioxidative enzyme activity and expressions via the Akt/Nrf2/ARE pathway.


Assuntos
Antioxidantes/metabolismo , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Traumatismo por Reperfusão Miocárdica/metabolismo , Canais de Cátion TRPV/antagonistas & inibidores , Canais de Cátion TRPV/metabolismo , Animais , Elementos de Resposta Antioxidante/efeitos dos fármacos , Elementos de Resposta Antioxidante/genética , Catalase/metabolismo , Cromonas/farmacologia , Peróxido de Hidrogênio/metabolismo , Masculino , Morfolinas/farmacologia , Morfolinas/uso terapêutico , Fator 2 Relacionado a NF-E2 , Proteína Oncogênica v-akt/antagonistas & inibidores , Proteína Oncogênica v-akt/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Pirróis/uso terapêutico , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Superóxido Dismutase/metabolismo
12.
Food Funct ; 10(8): 4593-4607, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31289794

RESUMO

Drug-induced nephrotoxicity contributes to acute kidney injury (AKI) and represents a major problem in the clinical setting. We investigated the possible involvement of NLRP3 inflammasome activation in methotrexate (MTX)-induced nephrotoxicity and the protective potential of ferulic acid (FA), pointing out the role of PPARγ and Nrf2/HO-1 signaling. Rats that received MTX showed a significant increase in circulating creatinine and urea, and kidney Kim-1 levels along with multiple histological alterations. Reactive oxygen species (ROS), malondialdehyde and nitric oxide levels showed a significant increase in the kidney of rats that received MTX, while antioxidant defenses were diminished. FA ameliorated kidney function markers, prevented histological alterations, suppressed ROS production and enhanced antioxidant defenses. FA inhibited MTX-induced inflammasome activation as showed by the decreased phosphorylation of NF-κB, and expression of NLRP3, caspase-1 and IL-1ß. MTX caused apoptosis marked by increased expression of BAX, cytochrome c and caspase-3, and suppressed Bcl-2, effects that were significantly reversed in FA-treated groups. In addition, FA up-regulated Nrf2/ARE/HO-1 signaling and PPARγ expression in the kidney of MTX-induced rats. In conclusion, activation of NLRP3 inflammasome may represent a new mechanism for MTX nephrotoxicity. FA up-regulated PPARγ and Nrf2 signaling, prevented overproduction of ROS, and suppressed NF-κB/NLRP3 inflammasome axis and apoptosis in the kidney of MTX-induced rats.


Assuntos
Lesão Renal Aguda/prevenção & controle , Ácidos Cumáricos/administração & dosagem , Heme Oxigenase (Desciclizante)/metabolismo , Inflamassomos/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , NF-kappa B/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , PPAR gama/metabolismo , Lesão Renal Aguda/induzido quimicamente , Lesão Renal Aguda/genética , Lesão Renal Aguda/metabolismo , Animais , Elementos de Resposta Antioxidante/efeitos dos fármacos , Heme Oxigenase (Desciclizante)/genética , Humanos , Inflamassomos/efeitos dos fármacos , Inflamassomos/genética , Rim/efeitos dos fármacos , Rim/metabolismo , Masculino , Metotrexato/efeitos adversos , Fator 2 Relacionado a NF-E2/genética , NF-kappa B/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , PPAR gama/genética , Substâncias Protetoras/administração & dosagem , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos
13.
Eur J Pharmacol ; 859: 172516, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31265839

RESUMO

Angiotensin II (Ang II) is a vasoactive peptide that elevates arterial blood pressure and leads to hypertension. Ang II has been reported to induce endothelial dysfunction by induction of apoptosis and oxidative stress in vascular endothelial cells. Sirtuin6 (SIRT6) has emerged as a critical regulator for modulating Ang II-induced injury of the cardiovascular system. However, little is known about the role of SIRT6 in regulating Ang II-induced injury in vascular endothelial cells. Here, our results showed that SIRT6 expression was decreased in vascular endothelial cells exposed to Ang II. This was accompanied by decreased cell viabilities as well as increased apoptosis and the production of reactive oxygen species. Functional experiments showed that the overexpression of SIRT6 significantly prohibited Ang II-induced apoptosis and reactive oxygen species generation, while silencing SIRT6 resulted in the opposite effect. Notably, our results showed that overexpression of SIRT6 resulted in a significant increase in the nuclear expression of nuclear factor erythroid 2-related factor 2 (Nrf2) and upregulated the expression of the Nrf2 target gene in vascular endothelial cells exposed to Ang II. Moreover, knockdown of Nrf2 significantly blocked the SIRT6-mediated protection effect against Ang II-induced apoptosis and reactive oxygen species generation. Taken together, these results demonstrate that SIRT6 overexpression alleviates Ang II-induced apoptosis and oxidative stress in vascular endothelial cells by promoting Nrf2 antioxidant signaling. Our study suggests that SIRT6 may serve as a potential therapeutic target for treating hypertension associated with endothelial dysfunction.


Assuntos
Angiotensina II/farmacologia , Elementos de Resposta Antioxidante/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Células Endoteliais/citologia , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Sirtuínas/metabolismo , Linhagem Celular , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Humanos , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Sirtuínas/genética
14.
Biochimie ; 165: 100-107, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31325480

RESUMO

High glucose (HG)-induced podocyte injury contributes to the pathogenesis of diabetic nephropathy, a severe complication of diabetes. Bromodomain-containing protein 4 (BRD4) has emerged as a critical regulator for cell injury. However, whether BRD4 participates in HG-induced podocyte injury remains unclear. In this study, we aimed to explore the potential role of BRD4 in regulating HG-induced podocyte injury and its underlying molecular mechanism. HG exposure significantly upregulated BRD4 in podocytes. BRD4 inhibition by small interfering RNA or its chemical inhibitor (JQ1) markedly repressed HG-induced apoptosis and reactive oxygen species (ROS) production. By contrast, BRD4 overexpression exacerbated HG-induced podocyte injury. Moreover, BRD4 inhibition potentiated nuclear factor (erythroid-derived 2)-like 2 (Nrf2) signaling associated with suppression of Kelch-like ECH-associated protein (Keap1). BRD4 inhibition promoted Nrf2 nuclear translocation and upregulated the transcriptional activity of Nrf2/antioxidant response element (ARE). However, Nrf2 silencing partially reversed BRD4-inhibition-mediated protection against HG-induced podocyte injury. Overall, these results suggest that BRD4 inhibition confers cytoprotection against HG injury in podocytes through potentiation of Nrf2/ARE antioxidant signaling. This finding implicates BRD4/Nrf2/ARE signaling in the pathogenesis of diabetic nephropathy.


Assuntos
Nefropatias Diabéticas/metabolismo , Falência Renal Crônica/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Proteínas Nucleares/fisiologia , Podócitos , Fatores de Transcrição/fisiologia , Animais , Elementos de Resposta Antioxidante , Linhagem Celular , Nefropatias Diabéticas/patologia , Falência Renal Crônica/patologia , Proteínas Nucleares/metabolismo , Podócitos/metabolismo , Podócitos/patologia , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais
15.
Anim Sci J ; 90(9): 1229-1238, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31264347

RESUMO

This study evaluated the effects of berberine on growth performance, immunity, haematological parameters, antioxidant capacity, and the expression of immune response-related genes in lipopolysaccharide (LPS)-challenged broilers. We assigned 120 one-day-old male broilers (Ross 308) to two treatment groups; each group included two subgroups, each of which included six replicates of five birds per replicate. The experiment used a 2 × 2 factorial arrangement with berberine treatment (0 or 60 mg/kg dietary) and challenge status [injection of saline (9 g/L w/v) or LPS (1.5 mg/kg body weight)] as the main factors. On days 14, 16, 18 and 20, broilers were intraperitoneally injected with LPS or physiological saline. Blood and liver samples were collected on day 21. Dietary berberine supplementation significantly alleviated the compromised average daily gain and average daily feed intake (p < 0.05) caused by LPS. The LPS challenge led to increased lymphocyte and white blood cell (WBC) counts, malondialdehyde (serum and liver) content, and immunoglobulin G and M, tumour necrosis factor-α (TNF-α) and interleukin-1ß (IL-1ß) expression (p < 0.05) and significantly reduced serum total superoxide dismutase (T-SOD) activity (p < 0.05). Dietary berberine significantly mitigated the LPS-induced decreases in the mRNA expression of nuclear factor-kappa B (NF-κB), TNF-α, IL-1ß, inducible nitrite synthase and cyclooxygenase-2 (p < 0.05) in the liver. In conclusion, berberine supplementation has a positive effect on LPS challenge, which may be related to the increase in antioxidant enzyme activity and inhibition of both NF-κB signalling and the expression of inflammatory mediators.


Assuntos
Antioxidantes/uso terapêutico , Berberina/uso terapêutico , Dieta/veterinária , Crescimento/efeitos dos fármacos , Inflamação/veterinária , Lipopolissacarídeos/imunologia , Animais , Elementos de Resposta Antioxidante , Antioxidantes/metabolismo , Berberina/metabolismo , Galinhas , Suplementos Nutricionais , Inflamação/dietoterapia , Inflamação/tratamento farmacológico , Lipopolissacarídeos/farmacologia , Masculino , NF-kappa B/efeitos dos fármacos , NF-kappa B/metabolismo , Doenças das Aves Domésticas/dietoterapia
16.
Chem Biol Interact ; 309: 108706, 2019 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-31194955

RESUMO

Oxidative-stress-induced osteoblast dysfunction plays an important role in the development and progression of osteoporosis. BTB and CNC homology 1 (Bach1) has been suggested as a critical regulator of oxidative stress; however, whether Bach1 plays a role in regulating oxidative-stress-induced osteoblast dysfunction remains unknown. Thus, we investigated the potential role and mechanism of Bach1 in regulating oxidative-stress-induced osteoblast dysfunction. Osteoblasts were treated with hydrogen peroxide (H2O2) to mimic a pathological environment for osteoporosis in vitro. H2O2 exposure induced Bach1 expression in osteoblasts. Functional experiments demonstrated that Bach1 silencing improved cell viability and reduced cell apoptosis and reactive oxygen species (ROS) production in H2O2-treated cells, while Bach1 overexpression produced the opposite effects. Notably, Bach1 inhibition upregulated alkaline phosphatase activity and osteoblast mineralization. Mechanism research revealed that Bach1 inhibition increased the activation of nuclear factor erythroid 2-related factor 2 (Nrf2)/antioxidant response element (ARE) signaling and upregulated heme oxygenase 1 and NAD(P)H:quinone oxidoreductase 1 mRNA expression. The Bach1 inhibition-mediated protective effect was partially reversed by silencing Nrf2 in H2O2-exposed osteoblasts. Taken together, these results demonstrate that Bach1 inhibition alleviates oxidative-stress-induced osteoblast apoptosis and dysfunction by enhancing Nrf2/ARE signaling activation, findings that suggest a critical role for the Bach1/Nrf2/ARE regulation axis in osteoporosis progression. Our study suggests that Bach1 may serve as a potential therapeutic target for treating osteoporosis.


Assuntos
Elementos de Resposta Antioxidante/genética , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Peróxido de Hidrogênio/farmacologia , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Fatores de Transcrição de Zíper de Leucina Básica/antagonistas & inibidores , Fatores de Transcrição de Zíper de Leucina Básica/genética , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Regulação para Baixo , Camundongos , Fator 2 Relacionado a NF-E2/antagonistas & inibidores , Fator 2 Relacionado a NF-E2/genética , Osteoblastos/citologia , Osteoblastos/metabolismo , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Espécies Reativas de Oxigênio/metabolismo
17.
Oxid Med Cell Longev ; 2019: 2761041, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31191797

RESUMO

Given the role of oxidative stress in PD pathogenesis and off-target side effects of currently available drugs, several natural phytochemicals seem to be promising in the management of PD. Here, we tested the hypothesis that scopoletin, an active principle obtained from Morinda citrifolia (MC), efficiently quenches oxidative stress through DJ-1/Nrf2 signaling and ameliorates rotenone-induced PD. Despite reducing oxidative stress, the administration of MC extract (MCE) has lessened protein aggregation as evident from decreased levels of nitrotyrosine and α-synuclein. In vitro studies revealed that scopoletin lessened rotenone-induced apoptosis in SH-SY5Y cells through preventing oxidative injury. Particularly, scopoletin markedly upregulated DJ-1, which then promoted the nuclear translocation of Nrf2 and transactivation of antioxidant genes. Furthermore, we found that scopoletin prevents the nuclear exportation of Nrf2 by reducing the levels of Keap1 and thereby enhancing the neuronal defense system. Overall, our findings suggest that scopoletin acts through DJ-1-mediated Nrf2 signaling to protect the brain from rotenone-induced oxidative stress and PD. Thus, we postulate that scopoletin could be a potential drug to treat PD.


Assuntos
Apoptose/efeitos dos fármacos , Morinda/química , Fator 2 Relacionado a NF-E2/metabolismo , Neurônios/citologia , Neurônios/efeitos dos fármacos , Escopoletina/farmacologia , Transdução de Sinais/efeitos dos fármacos , Animais , Elementos de Resposta Antioxidante/fisiologia , Western Blotting , Citometria de Fluxo , Masculino , Estresse Oxidativo/efeitos dos fármacos , Agregados Proteicos , Ratos
18.
BMC Complement Altern Med ; 19(1): 139, 2019 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-31221142

RESUMO

BACKGROUND: Several studies have found that caffeic acid (CA), a well-known phytochemical, displays important antioxidant and anti-cancer activities. However, no evidence exists on the protective effect and its mechanisms that CA treatment alone has against oxidative stress induced by tert-butyl hydroperoxide (t-BHP) in HepG2 cells. METHODS: Hepatoprotective activities such as cell viability, mRNA expression, and report gene assay were measured using HepG2 cell. Three types of genes and proteins related with detoxification in liver were used for measuring the hepatoprotective effects. Statistical analysis was performed using one-way ANOVA test and differences among groups were evaluated by Tukey's studentized range tests. RESULTS: The present study indicate that treatment with CA up-regulates heme oxygenase-1 (HO-1) and glutamate-cysteine ligase (GCL) mRNA and protein expressions in a CA-dose-dependent manner. In addition, translocation of nuclear factor-E2 p45-related factor (Nrf2) from the cytoplasm to the nucleus and phosphorylation of extracellular signal-regulated kinase, ERK and c-Jun N-terminal kinase, JNK which have been shown to be involved in mitogen-activated protein kinases, MAPKs are significantly enhanced by CA treatment. Furthermore, in cell nuclei, CA enhances the 5'-flanking regulatory region of human antioxidant response element (ARE) and activates the ARE binding site. CONCLUSION: Therefore, CA proved to be a stimulant of the expression of detoxification enzymes such as HO-1, GCLC, and GCLM through the ERK/Nrf2 pathway, and it may be an effective chemoprotective agent for protecting liver damage against oxidative damage.


Assuntos
Ácidos Cafeicos/farmacologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Neoplasias Hepáticas/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Substâncias Protetoras/farmacologia , terc-Butil Hidroperóxido/toxicidade , Elementos de Resposta Antioxidante/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/genética , Glutamato-Cisteína Ligase/genética , Glutamato-Cisteína Ligase/metabolismo , Heme Oxigenase-1/genética , Heme Oxigenase-1/metabolismo , Células Hep G2 , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/genética , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Neoplasias Hepáticas/genética , Fator 2 Relacionado a NF-E2/metabolismo , Espécies Reativas de Oxigênio/metabolismo
19.
Chem Biol Interact ; 309: 108705, 2019 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-31199929

RESUMO

MicroRNAs have emerged as critical mediators of cerebral ischaemia/reperfusion injury. Recent studies have demonstrated that microRNA-302b-3p (miR-302b-3p) plays an important role in regulating apoptosis and oxidative stress in various cells. However, whether miR-302b-3p is involved in regulating cerebral ischaemia/reperfusion injury-induced neuronal apoptosis and oxidative stress remains unknown. In the present study, we explored the potential function and molecular mechanism of miR-302b-3p in oxygen-glucose deprivation/re-oxygenation (OGD/R)-induced neuronal injury, using an in vitro model of cerebral ischaemia/reperfusion injury. We found that miR-302b-3p expression was up-regulated by OGD/R treatment in neurons. The inhibition of miR-302b-3p improved cell viability, and reduced apoptosis and the production of reactive oxygen species, showing a protective effect against OGD/R-induced injury. Interestingly, miR-302b-3p was shown to target and modulate murine fibroblast growth factor 15 (FGF15). Moreover, our results showed that miR-302b-3p down-regulation contributed to the promotion of nuclear factor erythroid 2-related factor 2 (Nrf2)/antioxidant response element (ARE)-mediated antioxidant signaling associated with the inactivation of glycogen synthase kinase-3ß. However, the knockdown of FGF15 significantly reversed the miR-302b-3p inhibition-mediated protective effect in OGD/R-treated neurons. Overall, these results demonstrated that miR-302b-3p inhibition confers a neuroprotective effect in OGD/R-treated neurons by up-regulating Nrf2/ARE antioxidant signaling via targeting FGF15, providing a novel target for neuroprotection in cerebral ischaemia/reperfusion injury.


Assuntos
Hipóxia Celular , Fatores de Crescimento de Fibroblastos/metabolismo , Glucose , MicroRNAs/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Regiões 3' não Traduzidas , Animais , Antagomirs/metabolismo , Elementos de Resposta Antioxidante/genética , Linhagem Celular , Sobrevivência Celular , Fatores de Crescimento de Fibroblastos/antagonistas & inibidores , Fatores de Crescimento de Fibroblastos/genética , Glucose/deficiência , Glicogênio Sintase Quinase 3 beta/metabolismo , Camundongos , MicroRNAs/antagonistas & inibidores , MicroRNAs/genética , Neurônios/citologia , Neurônios/metabolismo , Neuroproteção , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Regulação para Cima
20.
Chem Biol Interact ; 309: 108701, 2019 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-31181187

RESUMO

Pelargonidin, a well-known natural anthocyanidin found in berries strawberries, blueberries, red radishes and other natural foods, has been found to possess health beneficial effects including anti-cancer effect. Herein, we investigated the effect of pelargonidin on cellular transformation in mouse skin epidermal JB6 (JB6 P+) cells induced by tumor promoter 12-O-tetradecanoylphorbol-13-acetate (TPA). Pelargonidin treatment significantly decreased colony formation and suppressed cell viability of JB6 P+ cells. Pelargonidin also induced the anti-oxidant response element (ARE)-luciferase activation in HepG2-C8 cells overexpressing the ARE-luciferase reporter. Knockdown of nuclear factor E2-related factor 2 (Nrf2) in shNrf2 JB6 P+ cells enhanced TPA-induced colony formation and attenuated pelargonidin's blocking effect. Pelargonidin reduced the protein levels of genes encoding methyltransferases (DNMTs) and histone deacetylases (HDACs). Importantly, pelargonidin decreased the DNA methylation in the Nrf2 promoter region of JB6 P+ cells and increased Nrf2 downstream target genes expression, such as NAD(P)H/quinone oxidoreductase 1 (NQO1) and heme oxygenase-1 (HO-1), involved in cellular protection. In summary, our results showed that pelargonidin blocks TPA-induced cell transformation. The possible molecular mechanisms of its potential anti-cancer effects against neoplastic transformation may be attributed to its activation of Nrf2-ARE signaling pathway and its cytoprotective effect.


Assuntos
Antocianinas/farmacologia , Desmetilação do DNA/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/metabolismo , Animais , Antocianinas/química , Elementos de Resposta Antioxidante/genética , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , DNA-Citosina Metilases/metabolismo , Células Epidérmicas/citologia , Células Epidérmicas/efeitos dos fármacos , Células Epidérmicas/metabolismo , Expressão Gênica/efeitos dos fármacos , Células Hep G2 , Histona Desacetilases/metabolismo , Humanos , Camundongos , Fator 2 Relacionado a NF-E2/antagonistas & inibidores , Fator 2 Relacionado a NF-E2/genética , Regiões Promotoras Genéticas , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Acetato de Tetradecanoilforbol/farmacologia
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