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1.
Gene ; 766: 145152, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-32979431

RESUMO

OBJECTIVE: Cerebrovascular disease is one of the major diseases that seriously harm human health currently. The purpose of this study is to find an effective treatment and clarify its mechanism of action to provide a new idea and drug target for the clinical treatment of ischemic cerebrovascular disease. METHODS: The microglia cell line (BV2 cell line) was cultured in vitro. Prepare a hypoxia ischemia cell model by OGD and simulate the pathophysiological process of ischemic cerebrovascular disease in vivo. According to the techniques of LDH Cytotoxicity Assay Kit, flow cytometry of Annexin V-FITC Apoptosis Detection Kit, Laser Confocal Fluorescence Immunostaining (Double staining method), enzyme-linked immunosorbent assay (ELISA), and Western blotting, BV2 cells are observed through morphology and function changes induced by OGD. Moreover, these techniques were used to analyze changes in key proteins expression of signal transduction pathway in ischemic cerebrovascular disease, to explore the mechanism of gastrodin on ischemic cerebrovascular disease, and to elucidate the available ways for cell protection following ischemia and hypoxia. RESULTS: Gastrodin has no obvious toxic effect on BV-2 cells under physiological conditions. The death rate of BV-2 cells increases as the time of hypoxia increase. In the absence of oxygen, Gastrodin has a protective effect on the survival of BV-2 cells. This protective effect is related to the reduction of apoptosis rate. It can also improve the hypoxic tolerance of BV-2 cells, and there is no obvious Gastrodin dose-dependence. Moreover, Gastrodin has dual effects on BV-2 cells. The dual role of Gastrodin is closely related to the expression of several proteins which can affect the MAPK signal transduction pathway. CONCLUSION: Gastrodin has a dual effect on microglia with OGD. On the one hand, Gastrodin can inhibit the inflammatory cytokines secreted by microglia and aggravate the inflammatory response; on the other hand, Gastrodin can promote the secretion of protective cytokines from microglia to reduce the inflammatory response.


Assuntos
Álcoois Benzílicos/farmacologia , Glucose/metabolismo , Glucosídeos/farmacologia , Oxigênio/metabolismo , Animais , Apoptose/efeitos dos fármacos , Hipóxia Celular/efeitos dos fármacos , Linhagem Celular , Camundongos , Microglia/efeitos dos fármacos , Microglia/metabolismo , Neuroproteção/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos
2.
Anticancer Res ; 40(9): 5071-5079, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32878795

RESUMO

BACKGROUND/AIM: Liver cancer has extremely poor prognosis. The cancerous tissues contain hypoxic regions, and the available drugs are poorly effective in hypoxic environments. NADPH oxidase 4 (NOX4), producing reactive oxygen species (ROS), may contribute to cancer malignancy under hypoxic conditions. However, its role in liver cancer has not been examined in detail. Our aim was to explore the effects of setanaxib, a recently developed selective NOX4 inhibitor, in liver cancer cells under hypoxic conditions. MATERIALS AND METHODS: Liver cancer cell lines (HepG2, HLE and Alexander) were treated with hypoxia-mimetic agent cobalt chloride. Cytotoxicity assays, immunoblot analysis and ROS detection assay were performed to detect the effect of setanaxib under hypoxic conditions. RESULTS: Setanaxib exhibited hypoxia-selective cytotoxicity and triggered apoptosis in cancer cells. Moreover, setanaxib caused mitochondrial ROS accumulation under hypoxic conditions. Treatment with antioxidants markedly attenuated setanaxib-induced cytotoxicity and apoptosis under hypoxic conditions. CONCLUSION: Setanaxib caused mitochondrial ROS accumulation in a hypoxia-selective manner and evoked cancer cell cytotoxicity by inducing apoptosis. Thus, setanaxib has a great potential as a novel anticancer compound under hypoxic conditions.


Assuntos
Antineoplásicos/farmacologia , Hipóxia Celular/efeitos dos fármacos , Hipóxia/metabolismo , Neoplasias Hepáticas/metabolismo , NADPH Oxidase 4/antagonistas & inibidores , Linhagem Celular Tumoral , Humanos , Mitocôndrias/metabolismo , NADPH Oxidases/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo
3.
Anticancer Res ; 40(8): 4687-4694, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32727793

RESUMO

BACKGROUND/AIM: The Japanese apricot "Prunus mume" is a traditional Japanese medicine. MK615, a compound extract from Prunus mume has been reported to have anti-tumor effects. Herein, we used 3D floating (3DF) culture to evaluate the anticancer effects of MK615 against human colorectal cancer (CRC) cells that contain mutant (mt) KRAS. MATERIALS AND METHODS: HKe3 cells exogenously expressing mtKRAS (HKe3-mtKRAS) were treated with MK615 in 3DF cultures. The protein levels of hypoxia-inducible factor 1 (HIF-1) and E-cadherin were quantified by western blotting. RESULTS: MtKRAS enhanced hypoxia tolerance via up-regulation of HIF-1. The expression of HIF-1 protein was suppressed by constitutive overexpression of E-cadherin in CRC HCT116 spheroids. MK615 increased the expression of E-cadherin and decreased the expression of HIF-1 in HKe3-mtKRAS. These results suggest that MK615 suppresses hypoxia tolerance by up-regulation of E-cadherin in CRC cells with mtKRAS. CONCLUSION: MK615 exhibits properties useful for the potential treatment of CRC patients with mtKRAS.


Assuntos
Antígenos CD/metabolismo , Caderinas/metabolismo , Hipóxia Celular/fisiologia , Neoplasias do Colo/metabolismo , Neoplasias Colorretais/metabolismo , Extratos Vegetais/farmacologia , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Regulação para Cima/efeitos dos fármacos , Hipóxia Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/patologia , Células HCT116 , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Prunus/química , Ativação Transcricional/efeitos dos fármacos
4.
J Vis Exp ; (160)2020 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-32568218

RESUMO

Pulmonary Hypertension (PH) is a pathophysiological condition, defined by a mean pulmonary arterial pressure exceeding 25 mm Hg at rest, as assessed by right heart catheterization. A broad spectrum of diseases can lead to PH, differing in their etiology, histopathology, clinical presentation, prognosis, and response to treatment. Despite significant progress in the last years, PH remains an uncured disease. Understanding the underlying mechanisms can pave the way for the development of new therapies. Animal models are important research tools to achieve this goal. Currently, there are several models available for recapitulating PH. This protocol describes a two-hit mouse PH model. The stimuli for PH development are hypoxia and the injection of SU5416, a vascular endothelial growth factor (VEGF) receptor antagonist. Three weeks after initiation of Hypoxia/SU5416, animals develop pulmonary vascular remodeling imitating the histopathological changes observed in human PH (predominantly Group 1). Vascular remodeling in the pulmonary circulation results in the remodeling of the right ventricle (RV). The procedures for measuring RV pressures (using the open chest method), the morphometrical analyses of the RV (by dissecting and weighing both cardiac ventricles) and the histological assessments of the remodeling (both pulmonary by assessing vascular remodeling and cardiac by assessing RV cardiomyocyte hypertrophy and fibrosis) are described in detail. The advantages of this protocol are the possibility of the application both in wild type and in genetically modified mice, the relatively easy and low-cost implementation, and the quick development of the disease of interest (3 weeks). Limitations of this method are that mice do not develop a severe phenotype and PH is reversible upon return to normoxia. Prevention, as well as therapy studies, can easily be implemented in this model, without the necessity of advanced skills (as opposed to surgical rodent models).


Assuntos
Hipertensão Pulmonar/induzido quimicamente , Hipertensão Pulmonar/patologia , Indóis/farmacologia , Pirróis/farmacologia , Animais , Hipóxia Celular/efeitos dos fármacos , Modelos Animais de Doenças , Fibrose , Ventrículos do Coração/efeitos dos fármacos , Ventrículos do Coração/fisiopatologia , Humanos , Concentração de Íons de Hidrogênio , Hipertensão Pulmonar/complicações , Hipertensão Pulmonar/fisiopatologia , Hipertrofia Ventricular Direita/complicações , Masculino , Camundongos , Artéria Pulmonar/efeitos dos fármacos , Artéria Pulmonar/fisiopatologia , Circulação Pulmonar/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/metabolismo , Remodelação Vascular/efeitos dos fármacos , Remodelação Ventricular/efeitos dos fármacos
5.
Toxicol Lett ; 331: 82-91, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32461003

RESUMO

Hypoxia-inducible factor 1 (HIF-1) is a critical nuclear transcription factor for adaptation to hypoxia; its regulatable subunit, HIF-1α, is a cytoprotective regulatory factor. We examined the effects of methylmercury (MeHg) in rat adrenal pheochromocytoma (PC12) cells and the rat hepatocyte cell line BRL. MeHg treatment led to time- and concentration-dependent toxicity in both lines with statistically significant cytotoxic effects at 5 µM and 10 µM in PC12 and BRL, respectively, at 0.5 h. HIF-1α protein levels were significantly decreased at 2.5 (PC12) and 5 (BRL) µM MeHg. Furthermore, MeHg reduced the protein levels of HIF-1α and its target genes (glucose transporter-1, vascular endothelial growth factor-A and erythropoietin). Overexpression of HIF-1α significantly attenuated MeHg-induced toxicity in both cell types. Notably, cobalt chloride, a pharmacological inducer of HIF-1α, significantly attenuated MeHg-induced toxicity in BRL but not PC12. In both cell lines, an inhibitor of prolyl hydroxylase, 3, 4-dihydroxybenzoic acid, and the proteasome inhibitor carbobenzoxy-L-leucyl-L-leucyl-L-leucinal(MG132), antagonized MeHg toxicity, while 2-methoxyestradiol, a HIF-1α inhibitor, significantly increased it. These data establish that: (a) neuron-like PC12 cells are more sensitive to MeHg than non-neuronal BRL cells; (b) HIF-1α plays a similar role in MeHg-induced toxicity in both cell lines; and (c) upregulation of HIF-1α offers general cytoprotection against MeHg toxicity in PC12 and BRL cell lines.


Assuntos
Hipóxia Celular/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Hepatócitos/efeitos dos fármacos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Compostos de Metilmercúrio/toxicidade , Neurônios/efeitos dos fármacos , Animais , Técnicas de Cultura de Células , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Células PC12 , RNA Mensageiro/metabolismo , Ratos , Transdução de Sinais , Regulação para Cima
6.
PLoS One ; 15(4): e0231272, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32271805

RESUMO

Connexin 43 (Cx43) may be important in cell death and survival due to cell-to-cell communication-independent mechanisms. In our previous study, we found that small G protein signaling modulator 3 (SGSM3), a partner of Cx43, contributes to myocardial infarction (MI) in rat hearts. Based on these previous results, we hypothesized that SGSM3 could also play a role in bone marrow-derived rat mesenchymal stem cells (MSCs), which differentiate into cardiomyocytes and/or cells with comparable phenotypes under low oxygen conditions. Cx43 and Cx43-related factor expression profiles were compared between normoxic and hypoxic conditions according to exposure time, and Sgsm3 gene knockdown (KD) using siRNA transfection was performed to validate the interaction between SGSM3 and Cx43 and to determine the roles of SGSM3 in rat MSCs. We identified that SGSM3 interacts with Cx43 in MSCs under different oxygen conditions and that Sgsm3 knockdown inhibits apoptosis and cardiomyocyte differentiation under hypoxic stress. SGSM3/Sgsm3 probably has an effect on MSC survival and thus therapeutic potential in diseased hearts, but SGSM3 may worsen the development of MSC-based therapeutic approaches in regenerative medicine. This study was performed to help us better understand the mechanisms involved in the therapeutic efficacy of MSCs, as well as provide data that could be used pharmacologically.


Assuntos
Apoptose/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Proteínas Monoméricas de Ligação ao GTP/metabolismo , Miócitos Cardíacos/metabolismo , Animais , Biomarcadores/metabolismo , Hipóxia Celular/efeitos dos fármacos , Conexina 43/metabolismo , Junções Comunicantes/efeitos dos fármacos , Junções Comunicantes/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Células-Tronco Mesenquimais/efeitos dos fármacos , Miócitos Cardíacos/efeitos dos fármacos , Oxigênio/farmacologia , Ratos Sprague-Dawley , Estresse Fisiológico/efeitos dos fármacos , Fatores de Tempo , Via de Sinalização Wnt/efeitos dos fármacos
7.
Phytother Res ; 34(9): 2397-2407, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32298011

RESUMO

High altitude cerebral edema (HACE) is a high altitude malady caused by acute hypobaric hypoxia (AHH), in which pathogenesis is associated with oxidative stress and inflammatory cytokines. Potentilla anserina L is mainly distributed in Tibetan Plateau, and its polysaccharide possesses many physiological and pharmacological properties. In the present study, the protective effect and potential treatment mechanism of Potentilla anserina L polysaccharide (PAP) in HACE were explored. First, we measured the brain water content and observed the pathological changes in brain tissues, furthermore, malondialdehyde (MDA), nitric oxide (NO), superoxide dismutase (SOD), and glutathione (GSH) were evaluated by kits. Finally, the protein contents and mRNA expressions of pro-inflammatory (IL-1ß, IL-6, TNF-α, vascular endothelial cell growth factor [VEGF], NF-κB, and hypoxia inducible factor-1 α [HIF-1α]) were detected by ELISA kits, RT-PCR, and western blotting. The results demonstrated that PAP reduced the brain water content, alleviated brain tissue injury, reduce the levels of MDA and NO, and increased the activity of SOD and GSH level. In addition, PAP blocking the NF-κB and HIF-1α signaling pathway activation inhibited the generation of downstream pro-inflammatory cytokines (IL-1ß, IL-6, TNF-α, and VEGF). Therefore, PAP has a potential to treat and prevent of HACE by suppression of oxidative stress and inflammatory response.


Assuntos
Edema Encefálico/tratamento farmacológico , Encéfalo/efeitos dos fármacos , Hipóxia Celular/efeitos dos fármacos , Polissacarídeos/uso terapêutico , Potentilla/química , Transdução de Sinais/efeitos dos fármacos , Animais , Encéfalo/patologia , Masculino , Camundongos , Polissacarídeos/farmacologia , Ratos , Ratos Wistar
8.
Life Sci ; 252: 117666, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32298737

RESUMO

AIMS: Euscaphic acid and Tormentic acid are aglycones of Kaji-ichigoside F1 and Rosamultin, respectively. These four compounds are pentacyclic triterpenoid, isolated from the subterranean root of the Potentilla anserina L. Based on the protective roles against hypoxia-induced apoptosis of Euscaphic acid and Tormentic acid in vascular endothelial cells, this study was designed to determine the mechanisms. MAIN METHODS: The model of hypoxic injuries in EA. hy926 cells was established. Through applications of PI3K/AKT inhibitor, LY294002 and ERK1/2 inhibitor, PD98059, we explored the relationships between pharmacodynamic mechanisms and PI3K/AKT or ERK 1/2 signaling pathway. The anti-hypoxic effects were studied by methyl-thiazolyl-tetrazolium (MTT) assay, Hematoxylin-Eosin (HE) staining, DAPI staining, and flow cytometry. The mechanisms of anti-mitochondrial apoptosis were explored by western blot. The expressions of p-ERK 1/2, ERK 1/2, p-AKT, AKT, p-NF-κB, NF-κB, Bcl-2, Bax, Cyt C, cleaved caspase-9 and cleaved caspase-3 were detected. KEY FINDINGS: Euscaphic acid protected vascular endothelial cells against hypoxia-induced apoptosis via ERK1/2 signaling pathway, and Tormentic acid brought its efficacy into full play via PI3K/AKT and ERK1/2 signaling pathways. In addition, PI3K/AKT signaling pathway positively regulated ERK1/2 pathway, and ERK1/2 pathway negatively regulated PI3K/AKT pathway. SIGNIFICANCE: This evidence provides theoretical and experimental basis for the following research on anti-hypoxic drugs of Potentilla anserina L.


Assuntos
Apoptose/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Triterpenos/farmacologia , Hipóxia Celular/efeitos dos fármacos , Linhagem Celular , Cromonas/farmacologia , Células Endoteliais/metabolismo , Flavonoides/farmacologia , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Morfolinas/farmacologia , Fosfatidilinositol 3-Quinase/metabolismo , Potentilla/química , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos
9.
Biochem Biophys Res Commun ; 525(3): 626-632, 2020 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-32122653

RESUMO

BACKGROUND: When proliferating tumor cells expand to areas distant from vascular sites, poor diffusion of oxygen and nutrients occur, generating a restrictive hypoxic gradient in which susceptible tumor cells die. The heterogeneous population surviving hypoxia and metabolic starvation include de-differentiated cancer stem cells (CSC), capable of self-renewing tumor-initiating cells (TICs), or those that divide asymmetrically to produce non-tumor-initiating differentiated (NTI-D) cell progeny. Under such restrictive conditions, both populations slowly proliferate, entering quiescence or senescence, when exiting from cell cycle progression. This may drive chemoresistance and tumor recurrence, since most anti-cancer treatments target rapidly proliferating cells. PURPOSE: Since persistent or additional stress may increase NTI-D cells conversion to TICs, we investigated whether nutrient depletion or hypoxia influence expression of tyrosinase, a crucial enzyme for melanin synthesis, and B16 melanoma survival, when exposed to iron-dependent cell death oxidative stress produced by the Fenton reaction, resembling ferroptosis. RESULTS: -a) proliferating B16 melanoma with 10% serum-supplementation (10%S) normoxically express hypoxia inducible factor 1α (HIF1α) but lose tyrosinase, in contrast to those transiently exposed to (SF) serum-free medium, in which both HIF1α and tyrosinase are co-expressed; b) in contrast to the resistance to SNP toxicity in (SF) cells with higher tyrosinase expression, those in (10%S) are killed by iron from nitroprusside/ferricyanide (SNP) irrespective of exogenous H2O2, in a reaction antagonized by the anti-oxidant and MEK inhibitor UO126; c) Moreover, under transient serum depletion, SNP cooperates with hypoxia (1.5% oxygen), prolonging B16 melanoma (SF) survival; d) the hypoxia mimetic CoCl2 inhibits proliferation-associated cyclin A, irrespective of SNP, in (10%S) cells or in transiently serum-depleted (SF) cells. However, only in the latter cells, CoCl2 but not SNP, induce loss of HIF1α and apoptosis-associated PARP cleavage; e) longer term adaptation to survive serum depletion, generates (SS) cells resistant to SNP toxicity, which aerobically co-express HIF1α and tyrosinase. In SS B16 melanoma, exogenous non-toxic 100 µM H2O2 super-induces the ratio of tyrosinase to HIF1α. However, co-treatment of SS-B16 cells with SNP plus exogenous H2O2, partly increases PARP cleavage by reciprocally decreasing tyrosinase expression. SIGNIFICANCE: - These results suggest that a phenotypic plasticity in response to depletion of nutrients and/or oxygen, helps decide whether melanoma cells undergo either death by ferroptosis, or resistance to it, when challenged by the same exogenous oxidative stress (iron ± H2O2).


Assuntos
Ferroptose/efeitos dos fármacos , Melanoma Experimental/patologia , Nitroprussiato/farmacologia , Soro/metabolismo , Animais , Butadienos/farmacologia , Hipóxia Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cobalto/farmacologia , Meios de Cultura Livres de Soro , Ciclina A/metabolismo , Peróxido de Hidrogênio/farmacologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Camundongos , Monofenol Mono-Oxigenase/metabolismo , Nitrilos/farmacologia , Poli(ADP-Ribose) Polimerases/metabolismo , Transferrina/deficiência , Transferrina/metabolismo
10.
Oxid Med Cell Longev ; 2020: 1750289, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32190168

RESUMO

Reactive oxygen species (ROS) are byproducts of a defective electron transport chain (ETC). The redox couples, GSH/GSSG and NAD+/NADH, play an essential role in physiology as internal defenses against excessive ROS generation by facilitating intracellular/mitochondrial (mt) redox homeostasis. Anoxia alone and anoxia/reoxygenation (A/R) are dissimilar pathological processes. In this study, we measured the impact of capsaicin (Cap) on these pathological processes using a primary cultured neonatal rat cardiomyocyte in vitro model. The results showed that overproduction of ROS was tightly associated with disturbed GSH/GSSG and NAD+/NADH suppressed mt complex I and III activities, decreased oxygen consumption rates, and elevated extracellular acidification rates. During anoxia or A/R period, these indices interact with each other causing the mitochondrial function to worsen. Cap protected cardiomyocytes against the different stages of A/R injury by rescuing NAD+/NADH, GSH/GSSG, and mt complex I/III activities and cellular energy metabolism. Importantly, Cap-mediated upregulation of 14-3-3η, a protective phosphoserine-binding protein in cardiomyocytes, ameliorated mt function caused by a disruptive redox status and an impaired ETC. In conclusion, redox pair, mt complex I/III, and metabolic equilibrium were significantly different in anoxia alone and A/R injury; Cap through upregulating 14-3-3η plays a protection against the above injury in cardiomyocyte.


Assuntos
Proteínas 14-3-3/metabolismo , Capsaicina/farmacologia , Mitocôndrias/metabolismo , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Regulação para Cima , Animais , Apoptose/efeitos dos fármacos , Hipóxia Celular/efeitos dos fármacos , Transporte de Elétrons/efeitos dos fármacos , Metabolismo Energético/efeitos dos fármacos , Glicólise/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Miócitos Cardíacos/efeitos dos fármacos , Oxirredução , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Regulação para Cima/efeitos dos fármacos
11.
Oxid Med Cell Longev ; 2020: 4253457, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32190173

RESUMO

Myocardial ischemic postconditioning- (IPo-) mediated cardioprotection against myocardial ischemia-reperfusion (IR) injury needs the activation of signal transducer and activator of transcription 3 (STAT3), which involves adiponectin (APN). APN confers its biological effects through AMP-activated protein kinase- (AMPK-) dependent and AMPK-independent pathways. However, the role of AMPK in APN-mediated STAT3 activation in IPo cardioprotection is unknown. We hypothesized that APN-mediated STAT3 activation in IPo is AMPK-independent and that APN through AMPK-dependent STAT3 activation facilitates IPo cardioprotection. Here, Sprague-Dawley rats were subjected to myocardial IR without or with IPo and/or APN. APN or IPo significantly improved postischemic cardiac function and reduced myocardial injury and oxidative stress, and their combination further attenuated postischemic myocardial injuries. APN or its combination with IPo but not IPo alone significantly increased AMPK activation and both nuclear and mitochondrial STAT3 activation, while IPo significantly enhanced mitochondrial but not nuclear STAT3 activation. In primarily isolated cardiomyocytes, recombined globular APN (gAd), hypoxic postconditioning (HPo), or their combination significantly attenuated hypoxia/reoxygenation-induced cell injury and increased nuclear and/or mitochondrial STAT3 activation. STAT3 inhibition had no impact on gAd or gAd in combination with HPo-induced AMPK activation but abolished their cellular protective effects. AMPK inhibition did not affect HPo cardioprotection but abolished gAd cardioprotection and disabled gAd to facilitate/enhance HPo cardioprotection and STAT3 activation. These results suggest that APN confers cardioprotection through AMPK-dependent and AMPK-independent STAT3 activation, while IPo confers cardioprotection through AMPK-independent mitochondrial STAT3 activation. Joint use of APN and IPo synergistically attenuated myocardial IR injury by activating STAT3 via distinct signaling pathways.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Adiponectina/farmacologia , Cardiotônicos/metabolismo , Núcleo Celular/metabolismo , Mitocôndrias/metabolismo , Fator de Transcrição STAT3/metabolismo , Proteínas Quinases Ativadas por AMP/antagonistas & inibidores , Animais , Hipóxia Celular/efeitos dos fármacos , Núcleo Celular/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Hemodinâmica/efeitos dos fármacos , Pós-Condicionamento Isquêmico , Masculino , Mitocôndrias/efeitos dos fármacos , Miocárdio/enzimologia , Miocárdio/patologia , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos
12.
Adv Exp Med Biol ; 1219: 35-49, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32130692

RESUMO

In 2018, 9.6 million deaths from cancer were estimated, being this disease the second leading cause of death worldwide. Notwithstanding all the efforts developed in prevention, diagnosis and new treatment approaches, chemoresistance seems to be inevitable, leading to cancer progression, recurrence and affecting the outcome of the disease. As more and more evidence support that cancer is an evolutionary and ecological process, this concept is rarely applied in the clinical context. In fact, cancer cells emerge and progress within an ecological niche - the tumor microenvironment - that is shared with several other cell types and that is continuously changing. Therefore, the tumor microenvironment imposes several selective pressures on cancer cells such as acidosis, hypoxia, competition for space and resources, immune predation and anti-cancer therapies, that cancer cells must be able to adapt to or will face extinction.In here, the role of the tumor microenvironment selective pressures on cancer progression will be discussed, as well as the targeting of its features/components as strategies to fight cancer.


Assuntos
Neoplasias/patologia , Microambiente Tumoral , Hipóxia Celular/efeitos dos fármacos , Humanos , Neoplasias/terapia , Microambiente Tumoral/efeitos dos fármacos
13.
Invest Ophthalmol Vis Sci ; 61(3): 1, 2020 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-32150252

RESUMO

Purpose: We recently discovered that a hypoxic environment is beneficial for meibomian gland (MG) function. The mechanisms underlying this effect are unknown, but we hypothesize that it is due to an increase in the levels of hypoxia-inducible factor 1α (HIF1α). In other tissues, HIF1α is the primary regulator of cellular responses to hypoxia, and HIF1α expression can be induced by multiple stimuli, including hypoxia and hypoxia-mimetic agents. The objective of this study was to test our hypothesis. Methods: Human eyelid tissues were stained for HIF1α. Immortalized human MG epithelial cells (IHMGECs) were cultured for varying time periods under normoxic (21% O2) or hypoxic (1% O2) conditions, in the presence or absence of the hypoxia-mimetic agent roxadustat (Roxa). IHMGECs were then processed for the analysis of cell number, HIF1α expression, lipid-containing vesicles, neutral and polar lipid content, DNase II activity, and intracellular pH. Results: Our results show that HIF1α protein is present in human MG acinar epithelial cells in vivo. Our findings also demonstrate that exposure to 1% O2 or to Roxa increases the expression of HIF1α, the number of lipid-containing vesicles, the content of neutral lipids, and the activity of DNase II and decreases the pH in IHMGECs in vitro. Conclusions: Our data support our hypothesis that the beneficial effect of hypoxia on the MG is mediated through an increased expression of HIF1α.


Assuntos
Células Epiteliais/citologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/fisiologia , Glândulas Tarsais/citologia , Idoso , Idoso de 80 Anos ou mais , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/fisiologia , Hipóxia Celular/efeitos dos fármacos , Hipóxia Celular/fisiologia , Células Cultivadas , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Feminino , Glicina/análogos & derivados , Glicina/farmacologia , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Isoquinolinas/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Metabolismo dos Lipídeos/fisiologia , Masculino , Glândulas Tarsais/efeitos dos fármacos , Glândulas Tarsais/metabolismo
14.
Sci Rep ; 10(1): 2896, 2020 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-32076073

RESUMO

Myocardial infarction (MI) is a leading cause of death worldwide. Reperfusion is considered as an optimal therapy following cardiac ischemia. However, the promotion of a rapid elevation of O2 levels in ischemic cells produces high amounts of reactive oxygen species (ROS) leading to myocardial tissue injury. This phenomenon is called ischemia reperfusion injury (IRI). We aimed at identifying new and effective compounds to treat MI and minimize IRI. We previously studied heart regeneration following myocardial injury in zebrafish and described each step of the regeneration process, from the day of injury until complete recovery, in terms of transcriptional responses. Here, we mined the data and performed a deep in silico analysis to identify drugs highly likely to induce cardiac regeneration. Fisetin was identified as the top candidate. We validated its effects in an in vitro model of MI/IRI in mammalian cardiac cells. Fisetin enhances viability of rat cardiomyocytes following hypoxia/starvation - reoxygenation. It inhibits apoptosis, decreases ROS generation and caspase activation and protects from DNA damage. Interestingly, fisetin also activates genes involved in cell proliferation. Fisetin is thus a highly promising candidate drug with clinical potential to protect from ischemic damage following MI and to overcome IRI.


Assuntos
Caspases/metabolismo , Citoproteção , Flavonoides/farmacologia , Miocárdio/enzimologia , Miocárdio/patologia , Espécies Reativas de Oxigênio/metabolismo , Animais , Animais Recém-Nascidos , Morte Celular/efeitos dos fármacos , Hipóxia Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Citoproteção/efeitos dos fármacos , Dano ao DNA , Avaliação Pré-Clínica de Medicamentos , Ativação Enzimática/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Modelos Biológicos , Miócitos Cardíacos/efeitos dos fármacos , Oxigênio , Ratos
15.
Nanoscale ; 12(6): 4051-4060, 2020 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-32022048

RESUMO

Hypoxia, one of the features of most solid tumors, can severely impede the efficiency of oxygen-dependent treatments such as chemotherapy, radiotherapy and type-II photodynamic therapy. Herein, a catalase-like nanozyme RuO2@BSA (RB) was first prepared through a biomineralization strategy, and a high efficiency near-infrared photosensitizer (IR-808-Br2) was further loaded into the protein shell to generate the safe and versatile RuO2@BSA@IR-808-Br2 (RBIR) for the imaging-guided enhanced phototherapy against hypoxic tumors. RB not only acts like a catalase, but also serves as a photothermal agent that speeds up the oxygen supply under near-infrared irradiation (808 nm). The loaded NIR photosensitizer could immediately convert molecular oxygen (O2) to cytotoxic singlet oxygen (1O2) upon the same laser irradiation. Results indicated that RBIR achieved enhanced therapeutic outcomes with negligible side effects. Features such as a simple synthetic route and imaging-guided and single-wavelength-excited phototherapy make the nanozyme a promising agent for clinical applications.


Assuntos
Antineoplásicos , Hipóxia Celular , Terapia com Luz de Baixa Intensidade/métodos , Fotoquimioterapia/instrumentação , Nanomedicina Teranóstica/métodos , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Biomineralização , Hipóxia Celular/efeitos dos fármacos , Hipóxia Celular/efeitos da radiação , Camundongos , Nanoestruturas/química , Neoplasias Experimentais
16.
Cancer Res ; 80(7): 1498-1511, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32041837

RESUMO

Glioblastoma (GBM) responses to bevacizumab are invariably transient with acquired resistance. We profiled paired patient specimens and bevacizumab-resistant xenograft models pre- and post-resistance toward the primary goal of identifying regulators whose targeting could prolong the therapeutic window, and the secondary goal of identifying biomarkers of therapeutic window closure. Bevacizumab-resistant patient specimens and xenografts exhibited decreased vessel density and increased hypoxia versus pre-resistance, suggesting that resistance occurs despite effective therapeutic devascularization. Microarray analysis revealed upregulated mesenchymal genes in resistant tumors correlating with bevacizumab treatment duration and causing three changes enabling resistant tumor growth in hypoxia. First, perivascular invasiveness along remaining blood vessels, which co-opts vessels in a VEGF-independent and neoangiogenesis-independent manner, was upregulated in novel biomimetic 3D bioengineered platforms modeling the bevacizumab-resistant microenvironment. Second, tumor-initiating stem cells housed in the perivascular niche close to remaining blood vessels were enriched. Third, metabolic reprogramming assessed through real-time bioenergetic measurement and metabolomics upregulated glycolysis and suppressed oxidative phosphorylation. Single-cell sequencing of bevacizumab-resistant patient GBMs confirmed upregulated mesenchymal genes, particularly glycoprotein YKL-40 and transcription factor ZEB1, in later clones, implicating these changes as treatment-induced. Serum YKL-40 was elevated in bevacizumab-resistant versus bevacizumab-naïve patients. CRISPR and pharmacologic targeting of ZEB1 with honokiol reversed the mesenchymal gene expression and associated stem cell, invasion, and metabolic changes defining resistance. Honokiol caused greater cell death in bevacizumab-resistant than bevacizumab-responsive tumor cells, with surviving cells losing mesenchymal morphology. Employing YKL-40 as a resistance biomarker and ZEB1 as a target to prevent resistance could fulfill the promise of antiangiogenic therapy. SIGNIFICANCE: Bevacizumab resistance in GBM is associated with mesenchymal/glycolytic shifts involving YKL-40 and ZEB1. Targeting ZEB1 reduces bevacizumab-resistant GBM phenotypes. GRAPHICAL ABSTRACT: http://cancerres.aacrjournals.org/content/canres/80/7/1498/F1.large.jpg.


Assuntos
Inibidores da Angiogênese/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Glioblastoma/tratamento farmacológico , Células-Tronco Neoplásicas/efeitos dos fármacos , Homeobox 1 de Ligação a E-box em Dedo de Zinco/metabolismo , Adulto , Idoso , Inibidores da Angiogênese/uso terapêutico , Animais , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Bevacizumab/farmacologia , Bevacizumab/uso terapêutico , Compostos de Bifenilo/farmacologia , Compostos de Bifenilo/uso terapêutico , Encéfalo/irrigação sanguínea , Encéfalo/patologia , Neoplasias Encefálicas/irrigação sanguínea , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Hipóxia Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proteína 1 Semelhante à Quitinase-3/metabolismo , Resistencia a Medicamentos Antineoplásicos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glioblastoma/irrigação sanguínea , Glioblastoma/genética , Glioblastoma/patologia , Células Endoteliais da Veia Umbilical Humana , Humanos , Lignanas/farmacologia , Lignanas/uso terapêutico , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica/patologia , Invasividade Neoplásica/prevenção & controle , Células-Tronco Neoplásicas/patologia , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/genética , Neovascularização Patológica/patologia , Microambiente Tumoral/efeitos dos fármacos , Regulação para Cima , Ensaios Antitumorais Modelo de Xenoenxerto , Adulto Jovem , Homeobox 1 de Ligação a E-box em Dedo de Zinco/antagonistas & inibidores
17.
ACS Appl Mater Interfaces ; 12(4): 4231-4240, 2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-31912727

RESUMO

Radiotherapy has been extensively used to treat cancer patients because it can effectively damage most solid tumors without penetration limits. A hypoxic microenvironment in solid tumors leads to severe radioresistance and expression of hypoxic inducible factor-1 (HIF-1), which results in poor efficacy of radiotherapy alone. Herein, we report the excellent efficacy of radiotherapy achieved using a new type of yolk-shell Cu2-xSe@PtSe (CSP) nanosensitizer functionalized with the HIF-1α inhibitor acriflavine (ACF). We prepare the CSP nanosensitizer through the interfacial redox reactions between chloroplatinic acid and Cu2-xSe nanoparticles (CS) and then functionalize the nanosensitizer with ACF through their electrostatic interactions. We show that the synthesized CSP nanosensitizer can arrest the cell cycle (i.e., at the gap 2/mitosis (G2/M) phases) of tumor cells to enhance their sensitivity to X-rays and decompose endogenous H2O2 into O2 to reduce hypoxia and increase the production of reactive oxygen species, which leads to severe damage to DNA double strands and apoptosis of tumor cells. We also show that the ACF on the surface of CSP nanoparticles can effectively reduce the expression of HIF-1α. All these effects lead to a low vascular endothelial growth factor, low density of microvessels in tumor, decreased cell proliferation, and increased cell apoptosis, which synergistically and drastically enhance the efficacy of radiotherapy. This work provides insights and guidance for developing novel nanosensitizers to enhance the efficacy of radiotherapy.


Assuntos
Acriflavina , Subunidade alfa do Fator 1 Induzível por Hipóxia , Nanopartículas Metálicas , Proteínas de Neoplasias , Neoplasias , Tolerância a Radiação/efeitos dos fármacos , Radiossensibilizantes , Células 3T3 , Acriflavina/química , Acriflavina/farmacologia , Animais , Hipóxia Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Feminino , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/antagonistas & inibidores , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Nanopartículas Metálicas/química , Nanopartículas Metálicas/uso terapêutico , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/metabolismo , Neoplasias/metabolismo , Neoplasias/patologia , Neoplasias/radioterapia , Radiossensibilizantes/química , Radiossensibilizantes/farmacologia , Terapia por Raios X
18.
Cell Mol Life Sci ; 77(16): 3077-3083, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31907561

RESUMO

Pancreatic cancer (PC) remains one of the most extremely lethal malignancies worldwide due to late diagnosis and early metastasis, with a 1-year overall survival rate of approximately 20%. The hypoxic microenvironment, induced by intratumoral hypoxia, promotes tumor invasion and progression, leading to chemotherapy or radiotherapy resistance and eventual mortality after treatment of PC. However, the role of the hypoxic microenvironment in PC is complicated and requires further investigation. In this article, we review recent advances regarding the regulation of malignant behaviors in PC, which provide insight into the potential of hypoxic microenvironment activation therapy for the therapeutic agents.


Assuntos
Antineoplásicos/uso terapêutico , Hipóxia Celular/efeitos dos fármacos , Hipóxia Celular/fisiologia , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/patologia , Progressão da Doença , Humanos , Microambiente Tumoral/fisiologia
19.
Int J Mol Sci ; 21(2)2020 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-31941116

RESUMO

Hypoxic cellular proliferation is a common feature of tumor cells and is associated with tumor progression. Therefore, the inhibition of hypoxic cellular proliferation is expected to regulate malignancy processes. Licochalcone A (LicA) is known to show inhibitory effects on cell growth in normoxia, but it is unclear whether LicA exerts similar effects in hypoxia. Here, we studied the inhibitory activity of LicA in the hypoxic cellular proliferation of tumor cells and its molecular mechanism using human cell lines derived from various tumors including neuroblastoma and colorectal cancer. LicA inhibited cell growth at a 50% inhibitory concentration between 7.0 and 31.1 µM in hypoxia. LicA significantly suppressed hypoxic induction of tropomyosin receptor kinase B (TrkB) gene expression at the transcription level. LicA also downregulated mRNA levels of the TrkB high-affinity ligand brain-derived neurotrophic factor, but not neurotrophin-4, another TrkB ligand, or glyceraldehyde-3-phosphate dehydrogenase, indicating that the inhibitory activity of LicA is selective. Since both LicA-treatment and TrkB-knockdown decreased activation of protein kinase B in hypoxia, LicA exerts its inhibitory effect against hypoxic cell growth through inhibition of the TrkB-AKT axis. These results suggest that LicA has therapeutic potential for malignant tumors including neuroblastoma and colorectal cancer.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/biossíntese , Chalconas/farmacologia , Neoplasias Colorretais/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glicoproteínas de Membrana/biossíntese , Proteínas de Neoplasias/biossíntese , Neuroblastoma/metabolismo , Receptor trkB/biossíntese , Hipóxia Celular/efeitos dos fármacos , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/patologia , Células HeLa , Humanos , Neuroblastoma/tratamento farmacológico , Neuroblastoma/patologia
20.
Biomed Pharmacother ; 122: 109700, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31918273

RESUMO

Hypoxia induces cardiomyocytes injury, which further triggers the occurrence and development of cardiovascular diseases. There is a paucity of specific treatment options available with proven efficacy. Chinese patented pharmaceutical product Salidroside (Sal) has potent efficacy on treating hypoxic injury. However, the molecular mechanism remains obscure. In the present study, a UPLC-QTOFMS-based metabolomic method combined with cell viability and apoptosis assays were established to explore the therapeutic mechanisms of Sal against hypoxic injury. Significant protective effects of Sal against inhibited cell viability and apoptosis induced by hypoxic injury were observed in the pharmacodynamic evaluation. Moreover, 40 significantly changed metabolites related to hypoxic injury were identified, of which, 26 can be significantly regulated by Sal. Metabolic pathway enrichment analysis revealed that the mechanisms of Sal against hypoxic injury may be attributed to modulating the disordered homeostasis of energy and lipid metabolism. The present study provides new experimental information on the pathogenesis of hypoxia, unravels the potential targeted metabolic pathways of Sal against hypoxia on the whole metabolic network and highlights the importance of metabolomics as a potential tool for deciphering drug-targeted metabolic pathways.


Assuntos
Hipóxia Celular/efeitos dos fármacos , Glucosídeos/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Redes e Vias Metabólicas/efeitos dos fármacos , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Fenóis/farmacologia , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Metabolômica/métodos , Ratos
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