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2.
Am J Physiol Cell Physiol ; 318(1): C137-C149, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31721616

RESUMO

Reactive oxygen species (ROS) are important signaling molecules mediating the exercise-induced adaptations in skeletal muscle. Acute exercise also drives the expression of genes involved in reesterification and glyceroneogenesis in white adipose tissue (WAT), but whether ROS play any role in this effect has not been explored. We speculated that exercise-induced ROS would regulate acute exercise-induced responses in WAT. To address this question, we utilized various models to alter redox signaling in WAT. We examined basal and exercise-induced gene expression in a genetically modified mouse model of reduced mitochondrial ROS emission [mitochondrial catalase overexpression (MCAT)]. Additionally, H2O2, various antioxidants, and the ß3-adrenergic receptor agonist CL316243 were used to assess gene expression in white adipose tissue culture. MCAT mice have reduced ROS emission from WAT, enlarged WAT depots and adipocytes, and greater pyruvate dehydrogenase kinase-4 (Pdk4) gene expression. In WAT culture, H2O2 reduced glyceroneogenic gene expression. In wild-type mice, acute exercise induced dramatic but transient increases in Pdk4 and phosphoenolpyruvate carboxykinase (Pck1) mRNA in both subcutaneous inguinal WAT and epididymal WAT depots, which was almost completely absent in MCAT mice. Furthermore, the induction of Pdk4 and Pck1 in WAT culture by CL316243 was markedly reduced in the presence of antioxidants N-acetyl-cysteine or vitamin E. Genetic and nutritional approaches that attenuate redox signaling prevent exercise- and ß-agonist-induced gene expression within WAT. Combined, these data suggest that ROS represent important mediators of gene expression within WAT.


Assuntos
Adipócitos/enzimologia , Tecido Adiposo Branco/enzimologia , Metabolismo Energético , Mitocôndrias/enzimologia , Quinase Piruvato Desidrogenase (Transferência de Acetil)/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Adipócitos/efeitos dos fármacos , Adipogenia , Tecido Adiposo Branco/efeitos dos fármacos , Agonistas de Receptores Adrenérgicos beta 3/farmacologia , Animais , Antioxidantes , Catalase/genética , Catalase/metabolismo , Metabolismo Energético/efeitos dos fármacos , Regulação Enzimológica da Expressão Gênica , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Mitocôndrias/efeitos dos fármacos , Oxidantes/farmacologia , Oxirredução , Fosfoenolpiruvato Carboxiquinase (GTP)/genética , Fosfoenolpiruvato Carboxiquinase (GTP)/metabolismo , Esforço Físico , Quinase Piruvato Desidrogenase (Transferência de Acetil)/genética , Transdução de Sinais , Fatores de Tempo , Técnicas de Cultura de Tecidos
3.
Int J Mol Sci ; 20(21)2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31683554

RESUMO

In our previous research, ten antioxidant pentapeptides including FYKWP, FTGMD, GFEPY, YLPYA, FPPYERRQ, GFYAA, FSGLR, FPYLRH, VPDDD, and GIEWA were identified from the hydrolysate of miiuy croaker (Miichthys miiuy) swim bladder. In this work, their protective function on H2O2-induced oxidative damage to human umbilical vein endothelial cells (HUVECs) was studied. Results indicated that there was no significant difference in the HUVEC viability between the normal group and the treated groups with the 10 pentapeptides at the concentration of 100 µM for 24 h (p < 0.05). Furthermore, FPYLRH of 100 µg/mL extremely significantly (p < 0.001) increased the viability (80.58% ± 5.01%) of HUVECs with H2O2-induced oxidative damage compared with that of the model group. The protective mechanism indicated that FPYLRH could extremely significantly (p < 0.001) increase the levels of superoxide dismutase (SOD) (211.36 ± 8.29 U/mg prot) and GSH-Px (53.06 ± 2.34 U/mg prot) and decrease the contents of reactive oxygen species (ROS) (139.1 ± 11.8% of control), malondialdehyde (MDA) (13.66 ± 0.71 nM/mg), and nitric oxide (NO) (4.36 ± 0.32 µM/L) at the concentration of 100 µM in HUVECs with H2O2-induced oxidative damage compared with those of the model group. In addition, FPYLRH dose-dependently protected DNA in oxidative damage HUVECs model. These results suggested that FPYLRH could significantly attenuate the H2O2-induced stress injury in HUVECs and might be used as a potential natural antioxidant in the functional food industries.


Assuntos
Antioxidantes/farmacologia , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Peróxido de Hidrogênio/farmacologia , Oligopeptídeos/farmacologia , Perciformes/metabolismo , Hidrolisados de Proteína/metabolismo , Sacos Aéreos/química , Sacos Aéreos/metabolismo , Sequência de Aminoácidos , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Proteínas de Peixes/química , Proteínas de Peixes/metabolismo , Células Endoteliais da Veia Umbilical Humana/citologia , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Oxidantes/farmacologia , Substâncias Protetoras/farmacologia , Hidrolisados de Proteína/química , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo
4.
J Pediatr Surg ; 54(12): 2509-2513, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31668400

RESUMO

PURPOSE: Lactoferrin has been used as a milk supplement to prevent disease progression in necrotizing enterocolitis. However, the underlying mechanism is still unclear. We hypothesize that lactoferrin administration can modulate intestinal epithelial cell injury. METHODS: We established an in vitro model of epithelial cell injury by treating rat intestinal epithelial cells IEC-18 and human Caco-2 cells with hydrogen peroxide (H2O2), while lactoferrin was added as treatment at the same time. Live/dead cells were detected by immunofluorescence. Gene expression of inflammatory markers interleukin-6 (IL-6), intestinal stem cells (Lgr5), and proliferation marker (Wnt/ß-catenin) were measured. Data was presented as mean ±â€¯SEM and compared using one-way ANOVA. A p-value <0.05 was considered significant. RESULTS: Compared to control cells, H2O2 induced cell death in both IEC-18 and Caco-2 cells, whereas treatment with lactoferrin maintained cell viability. In addition, lactoferrin reduced gene expression of IL-6, while it increased gene expression of Lgr5 and Wnt/ß-catenin. CONCLUSIONS: Intestinal cell injury can be induced by exposure to H2O2, mimicking epithelial damage during intestinal injury. This damage can be reversed by lactoferrin administration by reducing inflammation and inducing cell proliferation. Lactoferrin can be a potential pharmacological intervention for the prevention and recovery of intestinal epithelial injury.


Assuntos
Anti-Infecciosos/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Expressão Gênica/efeitos dos fármacos , Lactoferrina/farmacologia , Animais , Células CACO-2 , Proliferação de Células/efeitos dos fármacos , Células Epiteliais/patologia , Humanos , Peróxido de Hidrogênio/farmacologia , Interleucina-6/genética , Mucosa Intestinal/patologia , Oxidantes/farmacologia , Ratos , Receptores Acoplados a Proteínas-G/genética , Proteínas Wnt/genética , beta Catenina/genética
5.
Nat Commun ; 10(1): 4400, 2019 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-31562333

RESUMO

A surveillance system in mammals constantly monitors cell activity to protect against aberrant proliferation in response to damage, injury and oncogenic stress. Here we isolate and culture connective tissue fibroblasts from highly regenerative mammals (Acomys and Oryctolagus) to determine how these cells interpret signals that normally induce cellular senescence in non-regenerating mammals (Mus and Rattus). While H2O2 exposure substantially decreases cell proliferation and increases p53, p21, p16, and p19 in cells from mice and rats, cells from spiny mice and rabbits are highly resistant to H2O2. Quantifying oxygen consumption and mitochondrial stability, we demonstrate that increased intracellular H2O2 is rapidly detoxified in regenerating species, but overwhelms antioxidant scavenging in cells from non-regenerative mammals. However, pretreatment with N-acetylcysteine (NAC) protects mouse and rat cells from ROS-induced cellular senescence. Collectively, our results show that intrinsic cellular differences in stress-sensing mechanisms partially explain interspecific variation in regenerative ability.


Assuntos
Senescência Celular , Fibroblastos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Acetilcisteína/farmacologia , Animais , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Tecido Conjuntivo/metabolismo , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Depuradores de Radicais Livres/farmacologia , Humanos , Peróxido de Hidrogênio/farmacologia , Camundongos , Murinae , Oxidantes/farmacologia , Coelhos , Ratos
6.
Nat Commun ; 10(1): 4028, 2019 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-31492904

RESUMO

Crosstalk is a major challenge to engineering sophisticated synthetic gene networks. A common approach is to insulate signal-transduction pathways by minimizing molecular-level crosstalk between endogenous and synthetic genetic components, but this strategy can be difficult to apply in the context of complex, natural gene networks and unknown interactions. Here, we show that synthetic gene networks can be engineered to compensate for crosstalk by integrating pathway signals, rather than by pathway insulation. We demonstrate this principle using reactive oxygen species (ROS)-responsive gene circuits in Escherichia coli that exhibit concentration-dependent crosstalk with non-cognate ROS. We quantitatively map the degree of crosstalk and design gene circuits that introduce compensatory crosstalk at the gene network level. The resulting gene network exhibits reduced crosstalk in the sensing of the two different ROS. Our results suggest that simple network motifs that compensate for pathway crosstalk can be used by biological networks to accurately interpret environmental signals.


Assuntos
Proteínas de Escherichia coli/genética , Escherichia coli/genética , Redes Reguladoras de Genes , Transdução de Sinais/genética , Escherichia coli/metabolismo , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Peróxido de Hidrogênio/farmacologia , Modelos Genéticos , Oxidantes/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Proteínas Repressoras/genética
7.
Blood Coagul Fibrinolysis ; 30(7): 324-330, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31490208

RESUMO

: The gut microbial metabolite, trimethylamine N-oxide (TMAO), was previously reported to induce platelet hypersensitivity, which leads to thrombotic risk. However, the molecular mechanism underlying the effects of TMAO on endothelial cells (EC), which is the primary vessel wall contact with the lumen, remains unclear. Here, we investigated the impact of TMAO on procoagulant activity (PCA) in EC and mice, for a possible link between microbiota and coagulation. To test the PCA of TMAO in EC, we performed one-stage clotting assays and converted into PCA. Antitissue factor (TF) antibody was used to test the TF role in PCA. Quantitative PCR was performed to measure the TF, thrombomodulin, IL-6, TF pathway inhibitor and IL-1b expressions at mRNA levels. To test the PCA and thrombotic risk by TMAO in mice, we challenged the mice with TMAO (8 mg/kg; 3 h) and measured the thrombin-anti-thrombin complex (TAT) and D-dimer levels as well as ferric chloride (FeCl3)-induced carotid artery thrombosis model. TMAO-induced TF expression in EC at mRNA and protein levels, dose-dependently. TF blocking experiment confirmed that the increased PCA by TMAO is TF-dependent. Also, mitogen-activated protein kinase pathway inhibitors abolished TMAO-induced TF expression. However, TMAO challenged mice failed to develop systemic activation of coagulation (TAT and D-dimer), as well as a FeCl3-induced carotid arterial thrombosis model. Our results indicated that TMAO triggered TF-dependent PCA via activation of nuclear factor-κB and downregulated thrombomodulin expression in human EC, but failed to develop systemic activation of coagulation in mice.


Assuntos
Coagulação Sanguínea/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Hemostasia/efeitos dos fármacos , Metilaminas/farmacologia , Animais , Células Cultivadas , Humanos , Camundongos , NF-kappa B/metabolismo , Oxidantes/farmacologia , Trombomodulina/efeitos dos fármacos , Trombomodulina/metabolismo
8.
Int J Mol Sci ; 20(18)2019 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-31533349

RESUMO

Derivatives of tirapazamine and other heteroaromatic N-oxides (ArN→O) exhibit promising antibacterial, antiprotozoal, and tumoricidal activities. Their action is typically attributed to bioreductive activation and free radical generation. In this work, we aimed to clarify the mechanism(s) of aerobic mammalian cell cytotoxicity of ArN→O performing the parallel studies of their reactions with NADPH:cytochrome P-450 reductase (P-450R), adrenodoxin reductase/adrenodoxin (ADR/ADX), and NAD(P)H:quinone oxidoreductase (NQO1); we found that in P-450R and ADR/ADX-catalyzed single-electron reduction, the reactivity of ArN→O (n = 9) increased with their single-electron reduction midpoint potential (E17), and correlated with the reactivity of quinones. NQO1 reduced ArN→O at low rates with concomitant superoxide production. The cytotoxicity of ArN→O in murine hepatoma MH22a and human colon adenocarcinoma HCT-116 cells increased with their E17, being systematically higher than that of quinones. The cytotoxicity of both groups of compounds was prooxidant. Inhibitor of NQO1, dicoumarol, and inhibitors of cytochromes P-450 α-naphthoflavone, isoniazid and miconazole statistically significantly (p < 0.02) decreased the toxicity of ArN→O, and potentiated the cytotoxicity of quinones. One may conclude that in spite of similar enzymatic redox cycling rates, the cytotoxicity of ArN→O is higher than that of quinones. This is partly attributed to ArN→O activation by NQO1 and cytochromes P-450. A possible additional factor in the aerobic cytotoxicity of ArN→O is their reductive activation in oxygen-poor cell compartments, leading to the formation of DNA-damaging species similar to those forming under hypoxia.


Assuntos
Antineoplásicos/farmacologia , Oxidantes/farmacologia , Tirapazamina/farmacologia , Antineoplásicos/química , Biomarcadores , Humanos , Estrutura Molecular , NAD(P)H Desidrogenase (Quinona)/metabolismo , NADP/metabolismo , Oxidantes/química , Oxirredução/efeitos dos fármacos , Espécies Reativas de Oxigênio , Tirapazamina/análogos & derivados , Tirapazamina/química
9.
PLoS One ; 14(9): e0222757, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31545823

RESUMO

Alzheimer's disease (AD) is a progressive neurodegenerative disorder, and is the most common type of cognitive impairment and dementia. There is a pressing need to improve the clinical efficacy and quality of life for AD patients, as limited treatments options for AD patients have been developed until now. In this study, we aim to investigate the protective effect of CH(II), a cerebroprotein hydrolysate consisted of abundant biological peptides, on preclinical model of AD. We found that CH(II) treatment effectively protects oxygen glucose deprivation (OGD)-induced N2A cell viability impairment and cell apoptosis. In addition, CH(II) significantly reduces H2O2-induced ROS accumulation and exhibits the protective activities against H2O2-induced oxidative injury. Intriguingly, we found that CH(II) treatment can effectively promote neurite outgrowth of N2A cells. Moreover, CH(II) obviously improve the cognitive and memorial function in scopolamine-induced amnesia mice model. Taken together, this study provides evidences of the neuroprotective activities of CH(II) and offers a potential therapeutic strategy for AD patients.


Assuntos
Doença de Alzheimer/fisiopatologia , Cognição/efeitos dos fármacos , Modelos Animais de Doenças , Espaço Intracelular/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cognição/fisiologia , Feminino , Glucose/metabolismo , Glucose/farmacologia , Peróxido de Hidrogênio/farmacologia , Espaço Intracelular/metabolismo , Camundongos Endogâmicos C57BL , Neurogênese/efeitos dos fármacos , Oxidantes/farmacologia , Oxigênio/metabolismo , Oxigênio/farmacologia
10.
Am J Physiol Cell Physiol ; 317(6): C1304-C1312, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31553646

RESUMO

Skeletal muscle weakness is associated with oxidative stress and oxidative posttranslational modifications on contractile proteins. There is indirect evidence that reactive oxygen/nitrogen species (ROS/RNS) affect skeletal muscle myofibrillar function, although the details of the acute effects of ROS/RNS on myosin-actin interactions are not known. In this study, we examined the effects of peroxynitrite (ONOO-) on the contractile properties of individual skeletal muscle myofibrils by monitoring myofibril-induced displacements of an atomic force cantilever upon activation and relaxation. The isometric force decreased by ~50% in myofibrils treated with the ONOO- donor (SIN-1) or directly with ONOO-, which was independent of the cross-bridge abundancy condition (i.e., rigor or relaxing condition) during SIN-1 or ONOO- treatment. The force decrease was attributed to an increase in the cross-bridge detachment rate (gapp) in combination with a conservation of the force redevelopment rate (kTr) and hence, an increase in the population of cross-bridges transitioning from force-generating to non-force-generating cross-bridges during steady-state. Taken together, the results of this study provide important information on how ROS/RNS affect myofibrillar force production which may be of importance for conditions where increased oxidative stress is part of the pathophysiology.


Assuntos
Contração Isométrica/efeitos dos fármacos , Molsidomina/análogos & derivados , Miofibrilas/efeitos dos fármacos , Miosinas/antagonistas & inibidores , Doadores de Óxido Nítrico/farmacologia , Oxidantes/farmacologia , Ácido Peroxinitroso/farmacologia , Actinas/antagonistas & inibidores , Actinas/química , Actinas/fisiologia , Animais , Contração Isométrica/fisiologia , Molsidomina/química , Molsidomina/farmacologia , Miofibrilas/fisiologia , Miofibrilas/ultraestrutura , Miosinas/química , Miosinas/fisiologia , Doadores de Óxido Nítrico/química , Estresse Oxidativo , Músculos Psoas/efeitos dos fármacos , Músculos Psoas/fisiologia , Músculos Psoas/ultraestrutura , Coelhos , Técnicas de Cultura de Tecidos
11.
Anesthesiology ; 131(3): 605-618, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31408447

RESUMO

WHAT WE ALREADY KNOW ABOUT THIS TOPIC: Diaphragm dysfunction and atrophy develop during controlled mechanical ventilation. Although oxidative stress injures muscle during controlled mechanical ventilation, it is unclear whether it causes autophagy or fiber atrophy. WHAT THIS ARTICLE TELLS US THAT IS NEW: Pretreatment of rats undergoing 24 h of mechanical ventilation with N-acetylcysteine prevents decreases in diaphragm contractility, inhibits the autophagy and proteasome pathways, but has no influence on the development of diaphragm fiber atrophy. BACKGROUND: Diaphragm dysfunction and atrophy develop during prolonged controlled mechanical ventilation. Fiber atrophy has been attributed to activation of the proteasome and autophagy proteolytic pathways. Oxidative stress activates the proteasome during controlled mechanical ventilation, but it is unclear whether it also activates autophagy. This study investigated whether pretreatment with the antioxidant N-acetylcysteine affects controlled mechanical ventilation-induced diaphragm contractile dysfunction, fiber atrophy, and proteasomal and autophagic pathway activation. The study also explored whether proteolytic pathway activity during controlled mechanical ventilation is mediated by microRNAs that negatively regulate ubiquitin E3 ligases and autophagy-related genes. METHODS: Three groups of adult male rats were studied (n = 10 per group). The animals in the first group were anesthetized and allowed to spontaneously breathe. Animals in the second group were pretreated with saline before undergoing controlled mechanical ventilation for 24 h. The animals in the third group were pretreated with N-acetylcysteine (150 mg/kg) before undergoing controlled mechanical ventilation for 24 h. Diaphragm contractility and activation of the proteasome and autophagy pathways were measured. Expressions of microRNAs that negatively regulate ubiquitin E3 ligases and autophagy-related genes were measured with quantitative polymerase chain reaction. RESULTS: Controlled mechanical ventilation decreased diaphragm twitch force from 428 ± 104 g/cm (mean ± SD) to 313 ± 50 g/cm and tetanic force from 2,491 ± 411 g/cm to 1,618 ± 177 g/cm. Controlled mechanical ventilation also decreased diaphragm fiber size, increased expression of several autophagy genes, and augmented Atrogin-1, MuRF1, and Nedd4 expressions by 36-, 41-, and 8-fold, respectively. Controlled mechanical ventilation decreased the expressions of six microRNAs (miR-20a, miR-106b, miR-376, miR-101a, miR-204, and miR-93) that regulate autophagy genes. Pretreatment with N-acetylcysteine prevented diaphragm contractile dysfunction, attenuated protein ubiquitination, and downregulated E3 ligase and autophagy gene expression. It also reversed controlled mechanical ventilation-induced microRNA expression decreases. N-Acetylcysteine pretreatment had no affect on fiber atrophy. CONCLUSIONS: Prolonged controlled mechanical ventilation activates the proteasome and autophagy pathways in the diaphragm through oxidative stress. Pathway activation is accomplished, in part, through inhibition of microRNAs that negatively regulate autophagy-related genes.


Assuntos
Acetilcisteína/farmacologia , Diafragma/efeitos dos fármacos , Diafragma/fisiopatologia , Oxidantes/farmacologia , Proteólise/efeitos dos fármacos , Respiração Artificial/efeitos adversos , Animais , Autofagia/efeitos dos fármacos , Modelos Animais de Doenças , Depuradores de Radicais Livres/farmacologia , Masculino , Atrofia Muscular/fisiopatologia , Ratos , Ratos Wistar
12.
Mol Cell Biochem ; 461(1-2): 91-102, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31375973

RESUMO

Peroxiredoxins (Prdxs) are antioxidant enzymes that catalyse the breakdown of peroxides and regulate redox activity in the cell. Peroxiredoxin 5 (Prdx5) is a unique member of Prdxs, which displays a wider subcellular distribution and substrate specificity and exhibits a different catalytic mechanism when compared to other members of the family. Here, the role of a key metabolic integrator coenzyme A (CoA) in modulating the activity of Prdx5 was investigated. We report for the first time a novel mode of Prdx5 regulation mediated via covalent and reversible attachment of CoA (CoAlation) in cellular response to oxidative and metabolic stress. The site of CoAlation in endogenous Prdx5 was mapped by mass spectrometry to peroxidatic cysteine 48. By employing an in vitro CoAlation assay, we showed that Prdx5 peroxidase activity is inhibited by covalent interaction with CoA in a dithiothreitol-sensitive manner. Collectively, these results reveal that human Prdx5 is a substrate for CoAlation in vitro and in vivo, and provide new insight into metabolic control of redox status in mammalian cells.


Assuntos
Coenzima A/metabolismo , Peroxirredoxinas/metabolismo , Processamento de Proteína Pós-Traducional , Animais , Análise Mutacional de DNA , Células HEK293 , Humanos , Masculino , Oxidantes/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Peroxidase/metabolismo , Ratos Sprague-Dawley , Ratos Wistar , Estresse Fisiológico/efeitos dos fármacos
13.
Int J Mol Sci ; 20(13)2019 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-31262038

RESUMO

Pro-oxidant therapy exploiting pro-oxidant drugs that can trigger cytotoxic oxidative stress in cancer cells has emerged as an innovative strategy for cancer-specific therapy. Piperlongumine (PL) has gained great interest as a novel pro-oxidant agent, because it has an ability to trigger cancer-specific apoptosis through the increase of oxidative stress in cancer cells. However, the use of PL is limited in the clinic because of its hydrophobic nature. In this study, chitosan- and fucoidan-based nanoparticles were prepared for the effective intracellular delivery of PL into cancer cells. Chitosan and fucoidan formed nanoparticles by ionic gelation. The chitosan- and fucoidan-based nanoparticles (CS-F NPs) effectively encapsulated PL, and increased its water solubility and bioavailability. CS-F NPs showed very low cytotoxicity in human prostate cancer cells, demonstrating its high potential for in vivo applications. The PL-loaded chitosan-fucoidan nanoparticles (PL-CS-F NPs) efficiently killed human prostate cancer cells via PL-induced intracellular reactive oxygen species (ROS) generation. This study demonstrates that CS-F NPs are promising natural polymer-based drug carriers for safe and effective PL delivery.


Assuntos
Antineoplásicos/administração & dosagem , Quitosana/análogos & derivados , Dioxolanos/administração & dosagem , Nanopartículas/química , Oxidantes/administração & dosagem , Polissacarídeos/química , Antineoplásicos/farmacologia , Morte Celular/efeitos dos fármacos , Linhagem Celular , Linhagem Celular Tumoral , Dioxolanos/farmacologia , Humanos , Nanopartículas/efeitos adversos , Oxidantes/farmacologia
14.
Mol Med Rep ; 20(2): 1499-1508, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31257486

RESUMO

Geniposide, as a type of iridoid glycoside, has antioxidative capacity. However, the mechanism underlying the effect of geniposide in cadmium (Cd)­induced osteoblast injury remains only partly elucidated. In the present study, Cell Counting Kit­8 (CCK­8) was used to determine MC­3T3­E1 cell viability. Flow cytometry was used to determine the rate of apoptosis and levels of reactive oxygen species (ROS). Oxidative stress­related factors were assessed using enzyme­linked immunosorbent method (ELISA). Quantitative real­time polymerase chain reaction (qPCR) and western blotting were used to evaluate apoptosis­ and bone formation­related genes and nuclear factor erythroid 2­related factor (Nrf2) signaling. It was demonstrated that geniposide increased the viability of the Cd­treated MC­3T3­E1 cells. Geniposide decreased apoptosis and ROS accumulation compared to these parameters in the Cd group. Geniposide attenuated oxidative stress­related factors, malondialdehyde and lactate dehydrogenase and increased antioxidant key enzyme superoxidase dismutase (SOD). The expression levels of Bax, Bcl­2 and survivin were modulated by geniposide. Additionally, the mRNA and protein expression of the receptor activator of NF­κB ligand (RANKL) and osterix were significantly increased, while osteoprotegerin was decreased by geniposide treatment compared to the Cd groups. Geniposide also enhanced Nrf2, heme oxygenase­1 (HO­1) and NAD(P)H quinone dehydrogenase 1 (NQO1) expression. The present study identified a potential agent for the treatment of Cd­induced osteoblast injury.


Assuntos
Antioxidantes/farmacologia , Cloreto de Cádmio/antagonistas & inibidores , Iridoides/farmacologia , Fator 2 Relacionado a NF-E2/genética , Oxidantes/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Animais , Cloreto de Cádmio/farmacologia , Linhagem Celular , Regulação da Expressão Gênica/efeitos dos fármacos , Heme Oxigenase-1/genética , Heme Oxigenase-1/metabolismo , L-Lactato Desidrogenase/genética , L-Lactato Desidrogenase/metabolismo , Malondialdeído/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , NAD(P)H Desidrogenase (Quinona)/genética , NAD(P)H Desidrogenase (Quinona)/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Osteoblastos/metabolismo , Oxidantes/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ligante RANK/genética , Ligante RANK/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Espécies Reativas de Oxigênio/agonistas , Espécies Reativas de Oxigênio/antagonistas & inibidores , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/genética , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Survivina/genética , Survivina/metabolismo , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismo
15.
Exp Mol Pathol ; 110: 104281, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31288012

RESUMO

BACKGROUND: Pressure ulcers (PUs) prevalence has been considered as an index for patient safety and cure quality of hospital and community. Skin cellular oxidative response damage is existed in the development of PUs. Angelica polysaccharide (AP) has the anti-oxidation function. Therefore, our goal was to investigate the mechanism of AP in relieving cellular oxidative damage. METHODS: Transfected HaCaT cells with miR-126 inhibitor, pre-treated by AP, and then treated by H2O2. CCK-8 assay and flow cytometry detection were set to test viability and apoptosis of cells respectively. qRT-PCR and western blot tested levels of miR-126 and oxidative damage relative factors. ROS assay tested the production of ROS in cells. RESULTS: Cellular oxidative response damage was induced by H2O2 at concentration of 300 µM. We found that AP could attenuate cellular oxidative response damage caused by H2O2 that it elevated cell viability, attenuated cell apoptosis and production of ROS and promoted activation of PI3K/AKT and mTOR signal pathways. Further, miR-126 was up-regulated by AP. The up-regulation of miR-126 could activate the PI3K/AKT and mTOR signal pathways. CONCLUSION: Our study demonstrated that AP attenuated cellular oxidative response damage in HaCaT cells by positively regulated miR-126.


Assuntos
Angelica/química , Queratinócitos/efeitos dos fármacos , MicroRNAs/genética , Estresse Oxidativo/efeitos dos fármacos , Polissacarídeos/farmacologia , Regulação para Cima/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Humanos , Peróxido de Hidrogênio/farmacologia , Queratinócitos/citologia , Queratinócitos/metabolismo , Oxidantes/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo , Regulação para Cima/genética
16.
Molecules ; 24(12)2019 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-31226759

RESUMO

Sorbus domestica leaves are a traditionally used herbal medicine recommended for the treatment of oxidative stress-related diseases. Dry leaf extracts (standardized by LC-MS/MS and LC-PDA) and nine model activity markers (polyphenols), were tested in scavenging assays towards six in vivo-relevant oxidants (O2•-, OH•, NO•, H2O2, ONOO-, HClO). Ascorbic acid (AA) and Trolox (TX) were used as positive standards. The most active extracts were the diethyl ether and ethyl acetate fractions with activities in the range of 3.61-20.03 µmol AA equivalents/mg, depending on the assay. Among the model compounds, flavonoids were especially effective in OH• scavenging, while flavan-3-ols were superior in O2•- quenching. The most active constituents were quercetin, (-)-epicatechin, procyanidins B2 and C1 (3.94-24.16 µmol AA/mg), but considering their content in the extracts, isoquercitrin, (-)-epicatechin and chlorogenic acid were indicated as having the greatest influence on extract activity. The analysis of the synergistic effects between those three compounds in an O2•- scavenging assay demonstrated that the combination of chlorogenic acid and isoquercitrin exerts the greatest influence. The results indicate that the extracts possess a strong and broad spectrum of antioxidant capacity and that their complex composition plays a key role, with various constituents acting complementarily and synergistically.


Assuntos
Antioxidantes/química , Oxidantes/química , Plantas Medicinais/química , Sorbus/química , Antioxidantes/farmacologia , Flavonoides/química , Flavonoides/farmacologia , Humanos , Peróxido de Hidrogênio/química , Oxidantes/farmacologia , Oxirredução/efeitos dos fármacos , Fenóis/química , Fitoterapia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Espectrometria de Massas em Tandem
17.
Nutrients ; 11(6)2019 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-31181639

RESUMO

BACKGROUND: 1,4-naphthoquinones, especially juglone, are known for their anticancer activity. However, plumbagin, lawsone, and menadione have been less investigated for these properties. Therefore, we aimed to determine the effects of plumbagin, lawsone, and menadione on C6 glioblastoma cell viability, ROS production, and mitochondrial function. METHODS: Cell viability was assessed spectrophotometrically using metabolic activity method, and by fluorescent Hoechst/propidium iodide nuclear staining. ROS generation was measured fluorometrically using DCFH-DA. Oxygen uptake rates were recorded by the high-resolution respirometer Oxygraph-2k. RESULTS: Plumbagin and menadione displayed highly cytotoxic activity on C6 cells (IC50 is 7.7 ± 0.28 µM and 9.6 ± 0.75 µM, respectively) and caused cell death by necrosis. Additionally, they increased the amount of intracellular ROS in a concentration-dependent manner. Moreover, even at very small concentrations (1-3 µM), these compounds significantly uncoupled mitochondrial oxidation from phosphorylation impairing energy production in cells. Lawsone had significantly lower viability decreasing and mitochondria-uncoupling effect, and exerted strong antioxidant activity. CONCLUSIONS: Plumbagin and menadione exhibit strong prooxidant, mitochondrial oxidative phosphorylation uncoupling and cytotoxic activity. In contrast, lawsone demonstrates a moderate effect on C6 cell viability and mitochondrial functions, and possesses strong antioxidant properties.


Assuntos
Antineoplásicos/farmacologia , Antioxidantes/farmacologia , Glioblastoma/metabolismo , Mitocôndrias/efeitos dos fármacos , Naftoquinonas/farmacologia , Oxidantes/farmacologia , Desacopladores/farmacologia , Animais , Antineoplásicos/uso terapêutico , Antioxidantes/uso terapêutico , Apoptose , Linhagem Celular Tumoral , Sobrevivência Celular , Glioblastoma/tratamento farmacológico , Mitocôndrias/metabolismo , Naftoquinonas/uso terapêutico , Oxidantes/uso terapêutico , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Fosforilação , Fitoterapia , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Ratos , Espécies Reativas de Oxigênio/metabolismo , Desacopladores/uso terapêutico , Vitamina K 3/farmacologia , Vitamina K 3/uso terapêutico
18.
Nucleic Acids Res ; 47(14): 7592-7604, 2019 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-31131413

RESUMO

To cope with harsh circumstances, bacterial cells must initiate cellular stress response programs, which demands the de novo synthesis of many stress defense proteins. Reactive oxygen species (ROS) is a universal environmental stressor for both prokaryotic cells and eukaryotic cells. However, the physiological burden that limits the survival of bacterial cells during oxidative stress remains elusive. Here we quantitatively characterize the cell growth and translational elongation rate of Escherichia coli cells treated with different doses of hydrogen peroxide. Cell growth is immediately arrested by low to moderate levels of hydrogen peroxide, but completely recovers after a certain lag time. The lag time depends positively on the dose of hydrogen peroxide. During the lag time, translational elongation rate drops by as much as ∼90% at initial stage and recovers to its normal state later, a phenomenon resulting from the dramatic alteration in cellular tRNA pools during oxidative stress. However, translational elongation is completely stalled at a certain threshold-level of hydrogen peroxide, at which cells ultimately fail to resume growth. Although the mRNA transcription of oxidative defense genes in oxyR regulon is dramatically induced upon hydrogen peroxide treatment, the extreme slow-down of translational elongation during high levels of hydrogen peroxide has severely compromised the timely synthesis of those oxidative defense proteins. Our study demonstrates that the tRNA-limited translational elongation is a key physiological bottleneck that the bacteria must overcome to counteract ROS, and the maintenance of translational elongation rate for timely synthesis of stress defense proteins is crucial for cells to smoothly get over the oxidative stress.


Assuntos
Escherichia coli/efeitos dos fármacos , Peróxido de Hidrogênio/farmacologia , Estresse Oxidativo , Biossíntese de Proteínas/efeitos dos fármacos , Adaptação Fisiológica/efeitos dos fármacos , Adaptação Fisiológica/genética , Relação Dose-Resposta a Droga , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Viabilidade Microbiana/efeitos dos fármacos , Viabilidade Microbiana/genética , Modelos Genéticos , Oxidantes/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Fatores de Tempo
19.
Toxins (Basel) ; 11(5)2019 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-31108999

RESUMO

Drinking water treatment plants throughout the world are increasingly facing the presence of toxic cyanobacteria in their source waters. During treatment, the oxidation of cyanobacteria changes cell morphology and can potentially lyse cells, releasing intracellular metabolites. In this study, a combination of techniques was applied to better understand the effect of oxidation with chlorine, ozone, potassium permanganate, and hydrogen peroxide on two cell cultures (Microcystis, Dolichospermum) in Lake Champlain water. The discrepancy observed between flow cytometry cell viability and cell count numbers was more pronounced for hydrogen peroxide and potassium permanganate than ozone and chlorine. Liquid chromatography with organic carbon and nitrogen detection was applied to monitor the changes in dissolved organic matter fractions following oxidation. Increases in the biopolymer fraction after oxidation with chlorine and ozone were attributed to the release of intracellular algal organic matter and/or fragmentation of the cell membrane. A novel technique, Enhanced Darkfield Microscopy with Hyperspectral Imaging, was applied to chlorinated and ozonated samples. Significant changes in the peak maxima and number of peaks were observed for the cell walls post-oxidation, but this effect was muted for the cell-bound material, which remained relatively unaltered.


Assuntos
Cianobactérias/efeitos dos fármacos , Oxidantes/farmacologia , Carga Bacteriana , Cloro/farmacologia , Cianobactérias/citologia , Citometria de Fluxo , Peróxido de Hidrogênio/farmacologia , Lagos/microbiologia , Microscopia , Oxirredução , Ozônio/farmacologia , Permanganato de Potássio/farmacologia , Análise Espectral , Poluentes da Água
20.
J Pharmacol Sci ; 140(1): 43-47, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31036520

RESUMO

This study investigated the effects of thiol and heme oxidants on responsiveness to cGMP generators in isolated rat aorta and pulmonary artery using an organ chamber. The nitric oxide (NO) donor sodium nitroprusside (SNP)-induced relaxation was impaired by exposure to the thiol oxidant diamide in both the aorta and the pulmonary artery, whereas the soluble guanylate cyclase (sGC) stimulator BAY 41-2272- or the sGC activator BAY 60-2770-induced relaxation was not affected. The impairment by diamide of SNP-induced aortic and pulmonary arterial relaxation was completely restored by post-treatment with the thiol reductant dithiothreitol. However, regardless of the vessel type, the relaxant response to SNP or BAY 41-2272 was impaired by exposure to the heme oxidant ODQ, whereas the response to BAY 60-2770 was enhanced. The ODQ-induced effects were reversed partially by post-treatment with the heme reductant dithionite. These findings indicate that thiol oxidation attenuates only the vascular responsiveness to NO donors and that heme oxidation attenuates the responsiveness to NO donors and sGC stimulators but augments that to sGC activators. Therefore, under oxidative stress, the order of usability of the vasodilators is suggested to be: NO donors < sGC stimulators < sGC activators.


Assuntos
Aorta/efeitos dos fármacos , Benzoatos/farmacologia , Compostos de Bifenilo/farmacologia , GMP Cíclico/metabolismo , Diamida/farmacologia , Hidrocarbonetos Fluorados/farmacologia , Doadores de Óxido Nítrico/farmacologia , Nitroprussiato/farmacologia , Oxidantes/farmacologia , Artéria Pulmonar/efeitos dos fármacos , Pirazóis/farmacologia , Piridinas/farmacologia , Compostos de Sulfidrila/farmacologia , Vasodilatação/efeitos dos fármacos , Vasodilatadores/farmacologia , Animais , Ditiotreitol/farmacologia , Técnicas In Vitro , Masculino , Estresse Oxidativo , Ratos Wistar , Guanilil Ciclase Solúvel/metabolismo
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