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1.
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
2.
Adv Exp Med Biol ; 1217: 187-210, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31898229

RESUMO

Cullin 3 (Cul3) family of ubiquitin ligases comprises three components, the RING finger protein RBX1, the Cul3 scaffold, and a Bric-a-brac/Tramtrack/Broad complex (BTB) protein. The BTB protein serves as a bridge to connect Cul3 to substrate and is functionally equivalent to the combination of substrate adaptor and linker in other Cullin complexes. Human genome encodes for ~180 BTB proteins, implying a broad spectrum of ubiquitination signals and substrate repertoire. Accordingly, Cul3 ubiquitin ligases are involved in diverse cellular processes, including cell division, differentiation, cytoskeleton remodeling, stress responses, and nerve cell functions. Emerging evidence has pointed to the prominent role of Cul3 ubiquitin ligases in cancer. This chapter will describe recent advances on the roles of Cul3 E3 ligase complexes in regulating various cancer hallmarks and therapeutic responses and the mutation/dysregulation of Cul3 substrate adaptors in cancer. In particular, we will focus on several extensively studied substrate adaptors, such as Keap1, SPOP, KLHL20, and LZTR1, and will also discuss other recently identified Cul3 adaptors with oncogenic or tumor-suppressive functions. We conclude that Cul3 ubiquitin ligases represent master regulators of human malignancies and highlight the importance of developing modulating agents for oncogenic/tumor-suppressive Cul3 E3 ligase complexes to prevent or intervene tumorigenesis.


Assuntos
Carcinogênese , Proteínas Culina/metabolismo , Neoplasias/metabolismo , Neoplasias/patologia , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Humanos , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Proteínas Nucleares/metabolismo , Proteínas Repressoras/metabolismo , Fatores de Transcrição/metabolismo
3.
Adv Exp Med Biol ; 1217: 211-223, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31898230

RESUMO

The ubiquitin proteasome pathway is one of the major regulatory tools used by eukaryotic cells. The evolutionarily conserved cullin family proteins can assemble as many as >600 distinct E3 ubiquitin ligase complexes that regulate diverse cellular pathways. In most of Cullin-RING ubiquitin ligase (CRL) complexes, separate linker and adaptor proteins build the substrate recognition module. Differently, a single BTB-containing adaptor molecule utilizing two protein interaction sites can link the CUL3 scaffold to the substrate, forming as many as 188 CUL3-BTB E3 ligase complexes in mammals. Here, we review the most recent studies on CRL3 complexes, with a focus on the model for CUL3 assembly with its BTB-containing substrate receptors. Also, we summarize the current knowledge of CRL3 substrates and their relevant biological functions. Next, we discuss the mutual exclusivity of somatic mutations in KEAP1, NRF2, and CUL3 in human lung cancer. Finally, we highlight new strategies to expand CUL3 substrates and discuss outstanding questions remaining in the field.


Assuntos
Domínio BTB-POZ , Proteínas Culina/metabolismo , Animais , Proteínas Culina/genética , Humanos , Proteína 1 Associada a ECH Semelhante a Kelch/genética , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Neoplasias Pulmonares/genética , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Especificidade por Substrato
5.
Toxicol Lett ; 319: 66-73, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31726083

RESUMO

Thallium ion (Tl+) and its neurotoxic products are widely known to cause severe neurological complications. However, the exact mechanism of action remains unknown, with limited therapeutic options available. This study aims to examine the toxic effects of Thallium (I) Nitrate (TlNO3) on primary hippocampal neurons of E17-E18 Wistar rat embryos, and the potential neuroprotective role of Nrf2- Keap1 signaling pathway against thallium-induced oxidative stress and mitochondrial dysfunction. TlNO3 induces a significant increase in reactive oxygen species levels and mitochondrial dysfunction in primary hippocampal neurons. Furthermore, the Nrf2-Keap1 signaling pathway played a protective role against TlNO3-induced hippocampal neuronal cytotoxicity. Moreover, mitochondrial fusion protein Mitofusin 2 (Mfn2) levels significantly decreased in hippocampal neurons when exposed to TlNO3, indicating that Mfn2 protein levels are linked to TlNO3-induced neurotoxicity. t-BHQ, a Nrf2 and phase II detoxification enzyme inducer, counteracted the oxidative damage in hippocampal neurons by activating the Nrf2-Keap1 signaling pathway after TlNO3 exposure; the activated Nrf2-Keap1 pathway could then maintain Mfn2 function by regulating Mfn2 protein expression. Thus, Nrf2-Keap1 pathway activation plays a protective role in Tl+-induced brain damage, and specific agonists have been identified to have great potential for treating thallium poisoning.


Assuntos
Hipocampo/efeitos dos fármacos , Proteína 1 Associada a ECH Semelhante a Kelch/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Tálio/toxicidade , Animais , Encefalopatias/induzido quimicamente , Encefalopatias/patologia , Encefalopatias/prevenção & controle , Feminino , Hipocampo/citologia , Proteínas de Membrana/efeitos dos fármacos , Proteínas de Membrana/metabolismo , Proteínas Mitocondriais/efeitos dos fármacos , Proteínas Mitocondriais/metabolismo , Cultura Primária de Células , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo
6.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 35(10): 878-885, 2019 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-31814563

RESUMO

Objective To investigate the effect of Legionella pneumophila (LP) on the autophagy flux of RAW264.7 macrophages and explore the molecular mechanism of the expression changes of autophagy-related factors. Methods Live LP and inactivated LP (MOI=10, 50, 100) were separately used to affect RAW264.7 for 1, 2 and 3 hours so as to screen the optimum condition of LP infection. The optimal condition for LP infection was MOI=50 and the infection time was 2 hours. After affected by rapamycin (RAPA) for 12 hours, RAW264.7 cells were then treated by live and inactivated LP for another 2 hours. Normal control group, RAPA group, live LP group, inactivated LP group, RAPA-treated live LP group, RAPA-treated inactivated LP group were designed. The pmCherry-C1-EGFP-LC3B double fluorescent labeling protein method was used to monitor the changes of autophagy flux. The relevant factor CLN3, histone deacetylase 6 (HDAC6), regulator of G protein signaling 19 (RGS19), tumor necrosis factor (TNF), cathepsin B (CTSB), GABA type A receptor associated protein like 2 (GABARAPL2), P62, microtubule-related protein 1 light chain 3 (LC3) were screened by gene array analysis. In order to validate the results of gene array, real-time quantitative PCR (RT-qPCR) was used to detect the mRNA levels of nuclear factor erythroid derived 2 like 2 (Nrf2), beclin1 and kelch like ECH associated protein 1 (Keap1); Western blot analysis was performed to measure the protein levels of Nrf2, beclin1 and Keap1. Results Both the live LP group and the inactivated LP group inhibited the autophagy flux compared with the normal control group and the RAPA group. Gene array analysis showed that in the live LP and inactivated LP groups, LC3 expression was down-regulated and P62 expression was up-regulated. The results of RT-qPCR and Western blot analysis were consistent with the gene array. The mRNA and protein levels of Keap1, beclin1, and Nrf2 significantly decreased, while the mRNA and protein levels of Nrf2 significantly increased. Conclusion LP can inhibit the autophagy of macrophage via activating Nrf2-Keap1 signaling pathway.


Assuntos
Autofagia , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Legionella pneumophila , Macrófagos/citologia , Fator 2 Relacionado a NF-E2/metabolismo , Animais , Camundongos , Células RAW 264.7 , Transdução de Sinais
7.
J Agric Food Chem ; 67(46): 12844-12853, 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31668063

RESUMO

Flazin is a ß-carboline-derived alkaloid found in Japanese fermented foods. Here, the potential of flazin as an antioxidant food was studied with particular reference to its effect on the Kelch-like ECH-associated protein 1 (Keap1)-nuclear factor erythroid 2-related factor 2 (Nrf2) system in human hepatocytes (C3A). Flazin and flazin analogues including the decarboxylated derivative perlolyrine were chemically synthesized and compared with each other and with chlorogenic acid and curcumin. Among these compounds, flazin showed the lowest cytotoxicity (IC50 < 500 µM) and the highest capacity to activate the Keap1-Nrf2 system. It provided the largest (>3-fold of the control) cytoprotection ability against a pro-oxidant, although its radical absorbance capacity was relatively low. Flazin increased the expressions of Nrf2-dependent phase II enzyme genes and their products (NQO1, GSTP, and GSH proteins). The strong cytoprotection ability of flazin associated with low log P (0-3) is shared by sulforaphane and 3,5-dihydroxy-4-methoxybenzyl alcohol, suggesting the potential value of flazin and flazin-rich foods for the prevention of oxidation-related health disorders.


Assuntos
Carbolinas/farmacologia , Furanos/farmacologia , Fator 2 Relacionado a NF-E2/metabolismo , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Proteína 1 Associada a ECH Semelhante a Kelch/genética , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Fator 2 Relacionado a NF-E2/genética , Transdução de Sinais/efeitos dos fármacos
8.
Chem Biol Interact ; 314: 108847, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31610155

RESUMO

Lead (Pb) is one of the toxic heavy metals that have several toxicological implications including cytotoxicities and oxidative stress. The release of reactive oxygen species (ROS) usually initiates lipid peroxidation and resulting in inflammation and tissue injury. However, the detailed identification of the Pb-produced lipid hydroperoxides has received little attention. Furthermore, the mechanisms behind such effects are less informed. Therefore, this study firstly investigated Pb-produced lipid hydroperoxides in human HepG2 cells using LC/MS. The effects of Pb on the antioxidant enzymes were additionally examined using qPCR and their dependent activities. As a protection trial, the ameliorative effects of rosmarinic (RMA) and ascorbic (ASA) acids on Pb-induced cytotoxicity and oxidative stress and their regulatory effects on Nrf2/Keap1 pathway were investigated. The achieved results confirmed cytotoxicity and oxidative damage of Pb on HepG2 cells. In addition, 20 lipid hydroperoxides (LOOH) were identified including 11 phosphatidylcholine hydroperoxides (PCOOH), 5 triacylglycerol hydroperoxides (TGOOH) and 4 cholesteryl ester hydroperoxides (CEOOH). The most dominant LOOH species were PCOOH 34:2, PCOOH 34:3, PCOOH 38:7, TGOOH 60:14, TGOOH 60:15, CEOOH 18:3 and CEOOH 20:4. Pb significantly downregulated Nrf2-regulated antioxidant enzymes at both the pretranscriptional and functional levels. Co-exposure of HepG2 cells to RMA and ASA significantly reduced Pb-produced adverse outcomes. This protection occurred via activation Nrf2-Keap1 antioxidant pathway.


Assuntos
Antioxidantes/metabolismo , Ácido Ascórbico/química , Cinamatos/química , Depsídeos/química , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Chumbo/química , Fator 2 Relacionado a NF-E2/metabolismo , Ácido Ascórbico/farmacologia , Cromatografia Líquida de Alta Pressão , Cinamatos/farmacologia , Depsídeos/farmacologia , Regulação para Baixo/efeitos dos fármacos , Células Hep G2 , Humanos , Chumbo/toxicidade , Peróxidos Lipídicos/análise , Peróxidos Lipídicos/metabolismo , Espectrometria de Massas , NAD(P)H Desidrogenase (Quinona)/genética , NAD(P)H Desidrogenase (Quinona)/metabolismo , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Superóxido Dismutase-1/genética , Superóxido Dismutase-1/metabolismo
9.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 50(3): 317-322, 2019 May.
Artigo em Chinês | MEDLINE | ID: mdl-31631596

RESUMO

Objective: To explore the molecular mechanism of ventilation induced lung injury (VILI) formation based on Keap1/Nfr2/ARE signaling pathway. Methods: The VILI model was established by excessive mechanical ventilation in SD rats. HE staining was used to detect the pathological changes of lung tissue in the control group, normal tidal volume (VT) group and large VT group (VT 40 mL/kg). The wet weight of lung tissue was detected in each group. Dry weight (W/D) ratio change; BCA method was used to detect the changes of total protein in bronchoalveolar lavage fluid (BALF) of each group; ELISA was used to detect interleukin-1ß (IL-1ß) and leukocyte in BALF and serum of each group. The content of 8-OHdG in the lung tissue was detected by IL-8 and the content of malondialdehyde (MDA) in the lung tissue was detected by TBA method. The NLRP3, ASC and caspase-1 proteins in macrophages were detected by Western blot. The changes of Keap1 and Nrf2 proteins in lung tissues were detected by RT-PCR. The expressions of SOD mRNA and HO-1 mRNA in lung tissues of each group were detected by RT-PCR. Results: Excessive mechanical ventilation could damage lung tissue, leading to alveolar rupture, inflammatory cell infiltration and erythrocytosis. Compared with the control group and normal VT group, the W/D value, 8-OHdG and MDA content in the large VT group, and total BALF, the contents of IL-1ß and IL-18 in protein, IL-1ß, IL-18 in serum increased significantly ( P<0.05). Compared with the control group and normal VT group, NLRP3, ASC, in macrophage of large VT group, the content of Keap1 protein in caspase-1 protein and lung tissue increased significantly ( P<0.05). The expression of Nrf2 protein, SOD mRNA and HO-1 mRNA in lung tissue decreased significantly. Conclusions: Large VT ventilation can cause acute inflammatory injury in lung tissue and lead to the occurrence of VILI. Inflammatory bodies of NLRP3 in alveolar macrophages are involved in this process, and the mechanism of NLRP3 inflammatory bodies is caused by hyperventilation in addition to mechanical injury. Decreased Keap1/Nrf2-ARE pathway inhibition and ROS clearance may also cause macrophage production of NLRP3 inflammatory bodies.


Assuntos
Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Transdução de Sinais , Lesão Pulmonar Induzida por Ventilação Mecânica/metabolismo , Animais , Líquido da Lavagem Broncoalveolar/química , Líquido da Lavagem Broncoalveolar/citologia , Heme Oxigenase (Desciclizante)/metabolismo , Interleucina-18/análise , Interleucina-1beta/análise , Pulmão , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Ratos , Ratos Sprague-Dawley , Superóxido Dismutase/metabolismo
10.
Nat Commun ; 10(1): 4190, 2019 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-31519898

RESUMO

The KRAS oncoprotein, a critical driver in 33% of lung adenocarcinoma (LUAD), has remained an elusive clinical target due to its perceived undruggable nature. The identification of dependencies borne through common co-occurring mutations are sought to more effectively target KRAS-mutant lung cancer. Approximately 20% of KRAS-mutant LUAD carry loss-of-function mutations in KEAP1, a negative regulator of the antioxidant response transcription factor NFE2L2/NRF2. We demonstrate that Keap1-deficient KrasG12D lung tumors arise from a bronchiolar cell-of-origin, lacking pro-tumorigenic macrophages observed in tumors originating from alveolar cells. Keap1 loss activates the pentose phosphate pathway, inhibition of which, using 6-AN, abrogated tumor growth. These studies highlight alternative therapeutic approaches to specifically target this unique subset of KRAS-mutant LUAD cancers.


Assuntos
Adenocarcinoma de Pulmão/genética , Neoplasias Pulmonares/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Adenocarcinoma de Pulmão/imunologia , Adenocarcinoma de Pulmão/metabolismo , Animais , Western Blotting , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/imunologia , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Linhagem Celular Tumoral , Feminino , Citometria de Fluxo , Imuno-Histoquímica , Proteína 1 Associada a ECH Semelhante a Kelch/genética , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Espécies Reativas de Oxigênio/metabolismo
11.
Chem Biodivers ; 16(11): e1900400, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31482617

RESUMO

The Keap1-Nrf2/ARE signaling pathway is an important defense system against exogenous and endogenous oxidative stress injury. The dysregulation of the signaling pathway is associated with many diseases, such as cancer, diabetes, and respiratory diseases. Over the years, a wide range of natural products has provided sufficient resources for the discovery of potential therapeutic drugs. Among them, polyphenols possess Nrf2 activation, not only inhibit the production of ROS, inhibit Keap1-Nrf2 protein-protein interaction, but also degrade Keap1 and regulate the Nrf2 related pathway. In fact, with the continuous improvement of natural polyphenols separation and purification technology and further studies on the Keap1-Nrf2 molecular mechanism, more and more natural polyphenols monomer components of Nrf2 activators have been gradually discovered. In this view, we summarize the research status of natural polyphenols that have been found with apparent Nrf2 activation and their action modes. On the whole, this review may guide the design of novel Keap1-Nrf2 activator.


Assuntos
Produtos Biológicos/farmacologia , Proteína 1 Associada a ECH Semelhante a Kelch/antagonistas & inibidores , Fator 2 Relacionado a NF-E2/antagonistas & inibidores , Polifenóis/farmacologia , Transdução de Sinais/efeitos dos fármacos , Produtos Biológicos/química , Humanos , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Estrutura Molecular , Fator 2 Relacionado a NF-E2/metabolismo , Polifenóis/química
12.
Oxid Med Cell Longev ; 2019: 6029876, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31396303

RESUMO

This study investigated the hepatoprotective effects of Morchella esculenta fruit body (ME) and the underlying mechanisms in mice with alcohol-induced acute liver injury. Systematic analysis revealed that ME contained 21 types of fatty acid, 17 types of amino acid, and 12 types of mineral. Subsequently, a mouse model of acute alcohol-induced liver injury was established by oral administration of alcohol for 14 days. Fourteen-day administration of ME prevented alcohol-induced increases in alanine aminotransferase and aspartate aminotransferase levels and reduced the activity of acetaldehyde dehydrogenase in blood serum and liver tissue. ME appears to regulate lipid metabolism by suppressing triglycerides, total cholesterol, and high-density lipoprotein in the liver. ME inhibited the production of inflammatory factors including chitinase-3-like protein 1 (YKL 40), interleukin-7 (IL-7), plasminogen activator inhibitor type 1 (PAI-1), and retinol-binding protein 4 (RBP4) in blood serum and/or liver tissue. ME treatment relieved the alcohol-induced imbalance in prooxidative and antioxidative signaling via nuclear factor-erythroid 2-related factor 2 (Nrf-2), as indicated by upregulation of superoxide dismutase-1, superoxide dismutase-2, catalase, heme oxygenase-1, and heme oxygenase-2 expression and downregulation of kelch-like ECH-associated protein 1 (Keap-1) in the liver. Moreover, ME reduced the levels of phosphorylated nuclear factor kappa-B kinase α/ß, inhibitor of nuclear factor kappa-B α and nuclear factor kappa-B p65 (NF-κB p65) in the liver. The hepatoprotective effects of ME against alcohol-induced acute liver injury were thus confirmed. The mechanism of action may be related to modulation of antioxidative and anti-inflammatory signaling pathways, partially via regulation of Nrf-2 and NF-κB signaling.


Assuntos
Ascomicetos/química , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Substâncias Protetoras/farmacologia , Transdução de Sinais/efeitos dos fármacos , Alanina Transaminase/sangue , Animais , Antioxidantes/metabolismo , Ascomicetos/metabolismo , Aspartato Aminotransferases/sangue , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/veterinária , Etanol/toxicidade , Heme Oxigenase-1/metabolismo , Mediadores da Inflamação/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Rim/metabolismo , Rim/patologia , Fígado/metabolismo , Fígado/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fator 2 Relacionado a NF-E2/metabolismo , NF-kappa B/metabolismo , Estresse Oxidativo/efeitos dos fármacos
13.
Nat Commun ; 10(1): 3759, 2019 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-31434890

RESUMO

Autophagy cargo recognition and clearance are essential for intracellular protein quality control. SQSTM1/p62 sequesters intracellular aberrant proteins and mediates cargo delivery for their selective autophagic degradation. The formation of p62 non-membrane-bound liquid compartments is critical for its function as a cargo receptor. The regulation of p62 phase separation/condensation has yet been poorly characterised. Using an unbiased yeast two-hybrid screening and complementary approaches, we found that DAXX physically interacts with p62. Cytoplasmic DAXX promotes p62 puncta formation. We further elucidate that DAXX drives p62 liquid phase condensation by inducing p62 oligomerisation. This effect promotes p62 recruitment of Keap1 and subsequent Nrf2-mediated stress response. The present study suggests a mechanism of p62 phase condensation by a protein interaction, and indicates that DAXX regulates redox homoeostasis, providing a mechanistic insight into the prosurvival function of DAXX.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Citoplasma/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Proteínas Nucleares/metabolismo , Proteínas de Ligação a RNA/metabolismo , Proteína Sequestossoma-1/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Autofagia/fisiologia , Linhagem Celular , Drosophila , Feminino , Técnicas de Silenciamento de Genes , Células HEK293 , Células HeLa , Humanos , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Masculino , Camundongos , Proteínas Nucleares/genética , Ligação Proteica , Dobramento de Proteína , Domínios e Motivos de Interação entre Proteínas
14.
Food Chem Toxicol ; 133: 110781, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31465820

RESUMO

The aim of the present study was to explore the protective effects of raspberry and its bioactive compound cyanidin 3-O-glucoside against H2O2-induced oxidative stress in HepG2 cells. We established a model of oxidative stress in HepG2 cells induced by H2O2 and examined the protein expression of Keap1/Nrf2. The antioxidant activity of raspberry extract was carried out measuring the level of reactive oxygen species (ROS), and the changes of phase II detoxification elements such as GSH level and CAT activity. Also the expression of proteins related to the Keap1/Nrf2 signaling was tested. The results revealed that raspberry extract significantly reduced the ROS levels in oxidative injured cells, increased GSH content and CAT activity, and activated the expression of proteins Keap1, Nrf2, HO-1, NQO1, and γ-GCS. These results taken together indicated that raspberry treatment could ameliorate H2O2-induced oxidative stress in HepG2 cells via Keap1/Nrf2 pathway.


Assuntos
Antioxidantes/farmacologia , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/farmacologia , Transdução de Sinais/efeitos dos fármacos , Antocianinas/farmacologia , Frutas/química , Glucosídeos/farmacologia , Células Hep G2 , Humanos , Peróxido de Hidrogênio/farmacologia , Rubus/química
15.
Food Chem Toxicol ; 133: 110758, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31412289

RESUMO

Various phytochemicals have been reported to protect against oxidative stress. However, the mechanism underlying has not been systematically evaluated, which limited their application in disease treatment. Nuclear factor erythroid 2-related factor 2 (Nrf2), a central transcription factor in oxidative stress response related to numerous diseases, is activated after dissociating from the cytoskeleton-anchored Kelch-like ECH-associated protein 1 (Keap1). The Keap1-Nrf2 protein-protein interaction has become an important drug target. This study was designed to clarify whether antioxidantive phytochemicals inhibit the Keap1-Nrf2 protein-protein interaction and activate the Nrf2-ARE signaling pathway efficiently. Molecular docking and 3D-QSAR were applied to evaluate the interaction effects between 178 antioxidant phytochemicals and the Nrf2 binding site in Keap1. The Nrf2 activation effect was tested on a H2O2-induced oxidative-injured cell model. Results showed that the 178 phytochemicals could be divided into high-, medium-, and low-total-score groups depending on their binding affinity with Keap1, and the high-total-score group consisted of 24 compounds with abundant oxygen or glycosides. Meanwhile, these compounds could bind with key amino acids in the structure of the Keap1-Nrf2 interface. Compounds from high-total-score group show effective activation effects on Nrf2. In conclusion, phytochemicals showed high binding affinity with Keap1 are promising new Nrf2 activators.


Assuntos
Antioxidantes/farmacologia , Proteína 1 Associada a ECH Semelhante a Kelch/antagonistas & inibidores , Fator 2 Relacionado a NF-E2/agonistas , Compostos Fitoquímicos/farmacologia , Ligação Proteica/efeitos dos fármacos , Animais , Antioxidantes/metabolismo , Antioxidantes/toxicidade , Sítios de Ligação , Humanos , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Simulação de Acoplamento Molecular , Estrutura Molecular , Fator 2 Relacionado a NF-E2/metabolismo , Células PC12 , Compostos Fitoquímicos/metabolismo , Compostos Fitoquímicos/toxicidade , Relação Quantitativa Estrutura-Atividade , Ratos
16.
Oxid Med Cell Longev ; 2019: 9372182, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31396308

RESUMO

The transcription factor NRF2 (nuclear factor erythroid 2-related factor 2) triggers the first line of homeostatic responses against a plethora of environmental or endogenous deviations in redox metabolism, proteostasis, inflammation, etc. Therefore, pharmacological activation of NRF2 is a promising therapeutic approach for several chronic diseases that are underlined by oxidative stress and inflammation, such as neurodegenerative, cardiovascular, and metabolic diseases. A particular case is cancer, where NRF2 confers a survival advantage to constituted tumors, and therefore, NRF2 inhibition is desired. This review describes the electrophilic and nonelectrophilic NRF2 activators with clinical projection in various chronic diseases. We also analyze the status of NRF2 inhibitors, which at this time provide proof of concept for blocking NRF2 activity in cancer therapy.


Assuntos
Fator 2 Relacionado a NF-E2/metabolismo , Doenças Cardiovasculares/tratamento farmacológico , Doenças Cardiovasculares/metabolismo , Doenças Cardiovasculares/patologia , Ensaios Clínicos como Assunto , Curcumina/química , Curcumina/uso terapêutico , Humanos , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Doenças Metabólicas/tratamento farmacológico , Doenças Metabólicas/metabolismo , Doenças Metabólicas/patologia , Fator 2 Relacionado a NF-E2/agonistas , Fator 2 Relacionado a NF-E2/antagonistas & inibidores , Doenças Neurodegenerativas/tratamento farmacológico , Doenças Neurodegenerativas/metabolismo , Doenças Neurodegenerativas/patologia , Estresse Oxidativo , Triterpenos/química , Triterpenos/uso terapêutico
17.
Int J Mol Sci ; 20(15)2019 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-31382550

RESUMO

Reactive oxygen species (ROS) are highly reactive signaling molecules that maintain redox homeostasis in mammalian cells. Dysregulation of redox homeostasis under pathological conditions results in excessive generation of ROS, culminating in oxidative stress and the associated oxidative damage of cellular components. ROS and oxidative stress play a vital role in the pathogenesis of acute kidney injury and chronic kidney disease, and it is well documented that increased oxidative stress in patients enhances the progression of renal diseases. Oxidative stress activates autophagy, which facilitates cellular adaptation and diminishes oxidative damage by degrading and recycling intracellular oxidized and damaged macromolecules and dysfunctional organelles. In this review, we report the current understanding of the molecular regulation of autophagy in response to oxidative stress in general and in the pathogenesis of kidney diseases. We summarize how the molecular interactions between ROS and autophagy involve ROS-mediated activation of autophagy and autophagy-mediated reduction of oxidative stress. In particular, we describe how ROS impact various signaling pathways of autophagy, including mTORC1-ULK1, AMPK-mTORC1-ULK1, and Keap1-Nrf2-p62, as well as selective autophagy including mitophagy and pexophagy. Precise elucidation of the molecular mechanisms of interactions between ROS and autophagy in the pathogenesis of renal diseases may identify novel targets for development of drugs for preventing renal injury.


Assuntos
Lesão Renal Aguda/genética , Autofagia/genética , Estresse Oxidativo/genética , Insuficiência Renal Crônica/genética , Lesão Renal Aguda/patologia , Proteína Homóloga à Proteína-1 Relacionada à Autofagia/genética , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteína 1 Associada a ECH Semelhante a Kelch/genética , Alvo Mecanístico do Complexo 1 de Rapamicina/genética , Fator 2 Relacionado a NF-E2/genética , Proteínas Quinases/genética , Proteínas de Ligação a RNA/genética , Espécies Reativas de Oxigênio/metabolismo , Insuficiência Renal Crônica/patologia
18.
Am J Chin Med ; 47(5): 1113-1131, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31352786

RESUMO

Pulmonary fibrosis (PF) is characterized by myofibroblast activation, which can be triggered by oxidative stress. In this study, we investigated the antifibrotic effect of the ethyl acetate extract of Salvia miltiorrhiza (EASM) on PF and examined the underlying molecular mechanism. EASM suppressed myofibroblast activation with reduced extracellular matrix deposition in the lungs of mice subjected to bleomycin (BLM) challenge, demonstrating the inhibitory effects on PF. EASM positively alleviated oxidative stress by upregulating nuclear factor-erythroid 2-related factor 2 (Nrf2) and concomitantly downregulating NADPH oxidase 4 (Nox4) in the lungs of BLM-treated mice. This effect was also observed in an in vitro model of transforming growth factor beta 1 (TGF-ß1)-stimulated fibroblast activation. EASM reduced reactive oxygen species (ROS) generation in fibroblasts by stabilizing Nrf2 protein with promoting kelch-like ECH-associated protein 1 (Keap1) degradation. Nrf2 knockdown in the lungs of BLM-treated mice diminished the inhibitory effects of EASM on fibrosis, providing evidence in vivo to address the unique role of Nrf2. Additionally, EASM inhibited TGF-ß1/Smad3 signaling by downregulating protein kinase C delta (PKC-δ) and Smad3 phosphorylation (p-Smad3), which led to suppression of the TGF-ß1-induced fibrogenic response. These results indicate that EASM exhibits potent antifibrotic activity in vitro and in vivo, which might be associated with activation of Nrf2 pathway and inhibition of TGF-ß1/Smad3 pathway. Our findings support that EASM may act as an effective antifibrotic remedy for PF.


Assuntos
Medicamentos de Ervas Chinesas/administração & dosagem , NADPH Oxidase 4/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Fibrose Pulmonar/tratamento farmacológico , Espécies Reativas de Oxigênio/metabolismo , Salvia miltiorrhiza/química , Animais , Feminino , Humanos , Proteína 1 Associada a ECH Semelhante a Kelch/genética , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Miofibroblastos/efeitos dos fármacos , Miofibroblastos/metabolismo , NADPH Oxidase 4/genética , Fator 2 Relacionado a NF-E2/genética , Fibrose Pulmonar/genética , Fibrose Pulmonar/metabolismo , Proteína Smad3/metabolismo , Fator de Crescimento Transformador beta/metabolismo
19.
J Agric Food Chem ; 67(32): 8794-8809, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31345023

RESUMO

Oxidative stress may play a critical role in the progression of liver disorders. Increasing interest has been given to the associations among diet, oxidative stress, gut-liver axis, and nonalcoholic fatty liver disease. Here, we investigated the effects of processed meat proteins on biomarkers of lipid homeostasis, hepatic metabolism, antioxidant functions, and gut microbiota composition in glutaredoxin1 deficient (Glrx1-/-) mice. The wild-type (WT) and Glrx1-/- mice were fed a soy protein diet (SPD), a dry-cured pork protein diet (DPD), a braised pork protein diet (BPD), and a cooked pork protein diet (CPD) at a dose of 20% of protein for 3 months. Serum and hepatic total cholesterol, serum endotoxin, hepatic liver droplet %, and antioxidant capacity were significantly increased in the CPD fed WT mice. In addition, CPD fed Glrx1-/- mice significantly increased total cholesterol, triacylglycerol, and pro-inflammatory cytokines which are accompanied by higher steatosis scores, intrahepatic lipid accumulation, and altered gene expression associated with lipid metabolism. Furthermore, hepatic gene expression of Nrf2/keap1 signaling pathway and its downstream signaling targets were determined using RT-qPCR. Glrx1 deficiency increased Nrf2 activity and expression of its target genes (GPx, catalase, SOD1, G6pd, and Bbc3), which was exacerbated by intake of CPD. Metagenomic analyses revealed that Glrx1-/- mice fed meat protein diets had higher abundances of Mucispirillum, Oscillibacter, and Mollicutes but lower abundances of Bacteroidales S24-7 group_norank, Blautia, and Anaerotruncus than their wild-type counterparts. In summary, Glrx1 deficiency induced an increase in serum biomarkers for lipid homeostasis, gut microbiota imbalance, and upregulation of Nrf2/Keap1 and antioxidant defense genes, which was aggravated by cooked meat protein diet.


Assuntos
Glutarredoxinas/genética , Inflamação/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Lipogênese , Fígado/metabolismo , Produtos da Carne/efeitos adversos , Fator 2 Relacionado a NF-E2/metabolismo , Animais , Colesterol/sangue , Citocinas/metabolismo , Feminino , Microbioma Gastrointestinal , Glutarredoxinas/deficiência , Humanos , Inflamação/genética , Inflamação/imunologia , Inflamação/microbiologia , Proteína 1 Associada a ECH Semelhante a Kelch/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fator 2 Relacionado a NF-E2/genética , Carne Vermelha , Transdução de Sinais , Triglicerídeos/sangue
20.
J Integr Neurosci ; 18(2): 153-161, 2019 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-31321956

RESUMO

We investigate whether ß-carotene, a known natural antioxidant, can reduce oxidative stress induced by traumatic brain injury. In addition, we investigated the underlying mechanism of traumatic brain injury focusing on the NF-E2-related factor (Nrf2) pathway. A controlled cortical impact model was used to mimic traumatic brain injury. Using this model, we evaluated brain edema, lesion volume, neurologic deficits, reactive oxygen species, and the expression of Nrf2-related protein markers. The results of our study demonstrated that cognitive performance and neural functions were improved with ß-carotene administration. In addition, ß-carotene reduced brain edema and reactive oxygen species levels after traumatic brain injury. Nrf2 nuclear accumulation was increased and was accompanied by decreased Keap1 expression. The expression of quinone oxidoreductase 1, a target gene of the Nrf2 signaling pathway was increased. However, lesion volume was not significantly reduced after ß-carotene treatment. Taken together, our data demonstrated that ß-carotene administration was neuroprotective and alleviated oxidative stress by modulating the Nrf2/Keap1- mediated antioxidant pathway in the traumatic brain injury model.


Assuntos
Lesões Encefálicas Traumáticas/metabolismo , Lesões Encefálicas Traumáticas/prevenção & controle , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Fármacos Neuroprotetores/administração & dosagem , beta Caroteno/administração & dosagem , Animais , Antioxidantes/administração & dosagem , Encéfalo/patologia , Lesões Encefálicas Traumáticas/patologia , Modelos Animais de Doenças , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Estresse Oxidativo/efeitos dos fármacos , Transdução de Sinais
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