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1.
IUBMB Life ; 72(7): 1379-1392, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32107872

RESUMO

This study purposed to examine the prospective curative role of lipoxin A4 (LXA4 ) in induced gastric ulcer in rats and explore the possible involvement of mitochondrial dynamics signaling pathway. Forty-eight male Wistar rats were divided into four groups: control, indomethacin (IND), IND + omeprazole (IND + Omez), and IND+ LXA4 groups. At the end of the experiment, the gastric pH, gastric fluid volume, total gastric acidity, ulcer index, and curative index were estimated. The gene expression of mitochondrial related protein 1 and mitofusin 2 were determined. In addition, some mitochondrial parameters include mitochondrial transmembrane potential, complex-I activity and reactive oxygen species were measured. Also, some gastric biochemical parameters, histopathological, and immunohistochemical analyses of the gastric mucosa were determined. We found that IND induced gastric ulcer, as manifested by the biochemical, histopathological, and immunohistochemical analyses. Both Omez and LXA4 treatment for 15 days alleviated the IND-induced gastric ulcer as explored by ameliorating the biochemical, histopathological, and immunohistochemical findings. We concluded that LXA4 mitigated the IND-induced gastric ulcer via improving the mitochondrial dynamic imbalance and mitochondrial dysfunction, in addition to its anti-apoptotic, anti-inflammatory, and antioxidant properties.


Assuntos
Anti-Inflamatórios/administração & dosagem , Indometacina/toxicidade , Lipoxinas/administração & dosagem , Mitocôndrias/efeitos dos fármacos , Dinâmica Mitocondrial , Úlcera Gástrica/tratamento farmacológico , Animais , Anti-Inflamatórios não Esteroides/toxicidade , Masculino , Estudos Prospectivos , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Úlcera Gástrica/induzido quimicamente , Úlcera Gástrica/metabolismo , Úlcera Gástrica/patologia
2.
Electromagn Biol Med ; 39(2): 176-182, 2020 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-32149540

RESUMO

In this study, a correlation between cell channel α-helices displacement and the mitochondrial transmembrane potential after exposure of 3, 7, 15 and 24 h of neuronal-like cells to a uniform magnetic field at the intensity of 2 mT was shown. Fourier Transform Infrared (FTIR) Spectroscopy and fluorescence techniques were used to analyze the secondary structure of protein content and mitochondrial transmembrane potential, respectively. The main result of this study was represented by a significant inverse relation between the mitochondrial transmembrane potential and the intensity of the Amide I band that can be associated with time exposure. Given that mitochondrial transmembrane potential should be related to the gating state of voltage-dependent anion channel (VDAC) in mitochondrial membrane, this result could have a relevant role in medicine. Indeed, VDAC's irregular behavior can be associated with several varieties of mitochondria-associated pathologies and various forms of cancer and neurodegeneration.


Assuntos
Nanopartículas Magnéticas de Óxido de Ferro/efeitos adversos , Potencial da Membrana Mitocondrial , Neurônios/citologia , Canais de Ânion Dependentes de Voltagem/química , Canais de Ânion Dependentes de Voltagem/metabolismo , Linhagem Celular Tumoral , Humanos , Conformação Proteica em alfa-Hélice , Fatores de Tempo
3.
J Cell Mol Med ; 23(5): 3429-3440, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30793492

RESUMO

Acidic microenvironment is commonly observed in ischaemic tissue. In the kidney, extracellular pH dropped from 7.4 to 6.5 within 10 minutes initiation of ischaemia. Acid-sensing ion channels (ASICs) can be activated by pH drops from 7.4 to 7.0 or lower and permeates to Ca2+ entrance. Thus, activation of ASIC1a can mediate the intracellular Ca2+ accumulation and play crucial roles in apoptosis of cells. However, the role of ASICs in renal ischaemic injury is unclear. The aim of the present study was to test the hypothesis that ischaemia increases renal epithelia cell apoptosis through ASIC1a-mediated calcium entry. The results show that ASIC1a distributed in the proximal tubule with higher level in the renal tubule ischaemic injury both in vivo and in vitro. In vivo, Injection of ASIC1a inhibitor PcTx-1 previous to ischaemia/reperfusion (I/R) operation attenuated renal ischaemic injury. In vitro, HK-2 cells were pre-treated with PcTx-1 before hypoxia, the intracellular concentration of Ca2+ , mitochondrial transmembrane potential (∆ψm) and apoptosis was measured. Blocking ASIC1a attenuated I/R induced Ca2+ overflow, loss of ∆ψm and apoptosis in HK-2 cells. The results revealed that ASIC1a localized in the proximal tubular and contributed to I/R induced kidney injury. Consequently, targeting the ASIC1a may prove to be a novel strategy for AKI patients.


Assuntos
Canais Iônicos Sensíveis a Ácido/metabolismo , Apoptose , Células Epiteliais/patologia , Rim/lesões , Traumatismo por Reperfusão/complicações , Animais , Cálcio/metabolismo , Caspase 3/metabolismo , Hipóxia Celular/efeitos dos fármacos , Linhagem Celular , Humanos , Espaço Intracelular/metabolismo , Túbulos Renais/efeitos dos fármacos , Túbulos Renais/lesões , Túbulos Renais/patologia , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Modelos Biológicos , Peptídeos/farmacologia , Traumatismo por Reperfusão/patologia , Venenos de Aranha/farmacologia
4.
J Biochem Mol Toxicol ; 33(8): e22337, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30958623

RESUMO

Elevated levels of saturated fatty acids show a strong cytotoxic effect in liver cells. Sirtuin 3 (SIRT3), a mitochondrially localized member of NAD+ -dependent deacetylase has been shown to protect hepatocytes against the oxidative stress. The role of SIRT3 on the cytotoxicity caused by fatty acids in liver cells is not fully understood. The aim of this study was to evaluate the expression level of SIRT3, oxidative stress, and mitochondrial impairments in human hepatoma HepG2 cells exposed to palmitic acid (PA). Our results showed that PA treatment caused the deposition of lipid droplets and resulted in an increased expression of tumor necrosis factor-α in a dose-dependent manner. Excessive accumulation of PA induces the reactive oxygen species formation and apoptosis while dissipating the mitochondrial transmembrane potential. The level of SIRT3 expression in both nuclear and mitochondrial fractions in HepG2 cells was decreased with the increase in PA concentrations. However, in the cytosolic fraction, the SIRT3 was undetectable. In conclusion, our results showed that PA caused an increase in inflammation and oxidative stress in HepG2 cells. The exposure of PA also resulted in the decline in transmembrane potential and an increase in apoptosis. The underexpression of nuclear and mitochondrial SIRT3 by PA suggests that the PA target the process that regulates the stress-related gene expression and mitochondrial functions.


Assuntos
Apoptose/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Mitocôndrias Hepáticas/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Ácido Palmítico/farmacologia , Sirtuína 3/metabolismo , Células Hep G2 , Humanos , Metabolismo dos Lipídeos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias Hepáticas/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
5.
Int J Med Sci ; 16(9): 1271-1282, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31588193

RESUMO

Nanosecond pulsed electric fields (nsPEFs) is emerged as a potential curative modality to ablate hepatocellular carcinoma (HCC). The application of local ablation is usually limited by insufficiency of liver function. While baicalin, a flavonoid isolated from Scutellaria baicalensis Georgi, has been proven to possess both anti-tumor and protective effects. Our study aimed to estimate different responses of hepatic cancer cells and hepatocytes to the combination of nsPEFs and baicalin. Cell viability, apoptosis and necrosis, mitochondrial transmembrane potential (MTP) and reactive oxygen species (ROS) were examined by CCK-8, FCM, JC-1 and fluorescent probe, respectively. After treatment by nsPEFs, most hepatocytes died by apoptosis, nevertheless, nearly all cancer cells were killed through necrosis. Low concentration of baicalin synergically enhanced nsPEFs-induced suppression and necrosis of HCC cells, nevertheless, the application of baicalin protected normal hepatocytes from the injury caused by nsPEFs, owing to elevating mitochondrial transmembrane potential and reducing ROS generation. Our work provided an advantageous therapy for HCC through the enhanced combination treatment of nsPEFs and baicalin, with which could improve the tumor-ablation effect and alleviate the injury of hepatic tissues simultaneously.


Assuntos
Carcinoma Hepatocelular/terapia , Terapia por Estimulação Elétrica/métodos , Flavonoides/farmacologia , Hepatócitos/efeitos dos fármacos , Neoplasias Hepáticas/terapia , Animais , Carcinoma Hepatocelular/metabolismo , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Flavonoides/efeitos adversos , Hepatócitos/metabolismo , Humanos , Neoplasias Hepáticas/metabolismo , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Espécies Reativas de Oxigênio/metabolismo
6.
Int J Mol Sci ; 20(4)2019 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-30781804

RESUMO

We examined the effects of the ferrocene-based histone deacetylase-3 inhibitor Pojamide (N¹-(2-aminophenyl)-N8-ferrocenyloctanediamide) and its two derivatives N¹-(2-aminophenyl)-N6-ferrocenyladipamide and N¹-(2-aminophenyl)-N8-ferroceniumoctanediamide tetrafluoroborate on triple-negative MDA-MB-231 breast cancer cells. Viability/growth assays indicated that only the first two compounds at 70 µM concentration caused an approximate halving of cell number after 24 h of exposure, whereas the tetrafluoroborate derivative exerted no effect on cell survival nor proliferation. Flow cytometric and protein blot analyses were performed on cells exposed to both Pojamide and the ferrocenyladipamide derivative to evaluate cell cycle distribution, apoptosis/autophagy modulation, and mitochondrial metabolic state in order to assess the cellular basis of the cytotoxic effect. The data obtained show that the cytotoxic effect of the two deacetylase inhibitors may be ascribed to the onset of non-apoptotic cell death conceivably linked to a down-regulation of autophagic processes and an impairment of mitochondrial function with an increase in intracellular reactive oxygen species. Our work expands the list of autophagy-regulating drugs and also provides a further example of the role played by the inhibition of autophagy in breast cancer cell death. Moreover, the compounds studied may represent attractive and promising targets for subsequent molecular modeling for anti-neoplastic agents in malignant breast cancer.


Assuntos
Inibidores de Histona Desacetilases/farmacologia , Histona Desacetilases/metabolismo , Neoplasias de Mama Triplo Negativas/enzimologia , Neoplasias de Mama Triplo Negativas/patologia , Apoptose/efeitos dos fármacos , Biomarcadores Tumorais/metabolismo , Ciclo Celular/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Feminino , Humanos , Metaloproteinases da Matriz/metabolismo , Espécies Reativas de Oxigênio/metabolismo
7.
Bioorg Med Chem ; 26(15): 4452-4460, 2018 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-30057155

RESUMO

Syzygium is a large genus of flowering plants, with several species, including the clove tree, used as important resources in the food and pharmaceutical industries. In our continuing search for anticancer agents from higher plants, a chloroform extract of the leaves and twigs of Syzygium corticosum collected in Vietnam was found to be active toward the HT-29 human colon cancer cell line. Separation of this extract guided by HT-29 cells and nuclear factor-kappa B (NF-κB) inhibition yielded 19 known natural products, including seven triterpenoids, three ellagic acid derivatives, two methylated flavonoids, a cyclohexanone, four megastigmanes, a small lactone, and an aromatic aldehyde. The full stereochemistry of (+)-fouquierol (2) was defined for the first time. Biological investigations showed that (+)-ursolic acid (1) is the major cytotoxic component of S. corticosum, which exhibited also potent activities in the NF-κB and mitochondrial transmembrane potential (MTP) inhibition assays conducted, with IC50 values of 31 nM and 3.5 µM, respectively. Several analogues of (+)-ursolic acid (1) were synthesized, and a preliminary structure-activity relationship (SAR) study indicated that the C-3 hydroxy and C-28 carboxylic acid groups and 19,20-dimethyl substitution are all essential in the mediation of the bioactivities observed for this triterpenoid.


Assuntos
Antineoplásicos Fitogênicos/síntese química , NF-kappa B/metabolismo , Syzygium/química , Triterpenos/química , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Células HT29 , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Conformação Molecular , NF-kappa B/antagonistas & inibidores , Extratos Vegetais/química , Folhas de Planta/química , Folhas de Planta/metabolismo , Relação Estrutura-Atividade , Syzygium/metabolismo , Triterpenos/síntese química , Triterpenos/farmacologia , Ácido Ursólico
8.
J Appl Toxicol ; 38(3): 329-340, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29027213

RESUMO

This study was performed to evaluate the protective efficacy of metoclopramide (MCP) against the organophosphates paraoxon (POX)- and malathion (MLT)-induced apoptosis in the murine L929 skin fibroblasts. L929 cells were exposed to either POX (10 nm) or 1.0 µm MLT in the absence and presence of increased concentrations of MCP. The protective effect of MCP on these organophosphate-stimulated apoptotic events was evaluated by flow cytometry analysis after staining with annexin-V/propidium iodide, processing and activation of the executioner caspase-3, cleavage of the poly-ADP ribose polymerase, fragmentation of the nucleosomal DNA and disruption of the mitochondrial membrane potential (Δψ). Our results showed that increased doses of MCP alone (≥10 µm) did not induce apoptosis or activation of caspase-3. Pretreatment of the cells with MCP attenuated all the apoptotic events triggered by the organophosphate compounds in a dose-dependent manner reaching ~70-80% protection when they were preincubated at 1 and 5 µm of the drug before the addition of POX and MLT, respectively. Interestingly, MCP did not offer a significant protective effect against the cytotoxicity of tumor necrosis factor-α, cisplatinum, etoposide or paclitaxel, which stimulate apoptosis by various mechanisms, suggesting that the anti-apoptotic effect of the drug is specific to organophosphates. The strong and specific anti-apoptotic activity of subclinical doses of MCP against the cytotoxicity of organophosphate compounds suggests its potential clinical application in treating their poisoning.


Assuntos
Antídotos/farmacologia , Apoptose/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Malation/toxicidade , Metoclopramida/farmacologia , Organofosfonatos/toxicidade , Paraoxon/toxicidade , Pele/efeitos dos fármacos , Animais , Caspase 3/metabolismo , Linhagem Celular , Citoproteção , Relação Dose-Resposta a Droga , Fibroblastos/metabolismo , Fibroblastos/patologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Poli(ADP-Ribose) Polimerases/metabolismo , Pele/metabolismo , Pele/patologia
9.
Heart Lung Circ ; 25(3): 296-302, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26631827

RESUMO

BACKGROUND: Peripheral blood lymphocytes exhibit changes that parallel those in failing cardiomyocytes. We hypothesised that mitochondrial transmembrane potential (MTP) and reactive oxygen species (ROS) levels of lymphocytes are associated with serum NT-proBNP and short-term prognosis in patients with chronic heart failure (CHF). METHODS: Fifty-four CHF patients and 30 controls were enrolled in this prospective study. Mitochondrial transmembrane potential and ROS levels of lymphocytes were evaluated by flow cytometry and reported as the JC-1 fluorescence ratio and DCF fluorescence intensity, respectively. Serum NT-proBNP levels and biochemical parameters were also examined. All the participants received follow-up to evaluate clinical end-points after eight months. RESULTS: Chronic heart failure patients had higher levels of DCF fluorescence intensity of lymphocytes and serum NT-proBNP, as well as lower levels of JC-1 fluorescence ratios compared with those of controls (all P<0.05). A closer relationship was found between Lg(DCF fluorescence intensity of lymphocytes) or JC-1 fluorescence ratio of lymphocytes and Lg(NT-proBNP) (both P<0.05) in CHF patients. During the eight-month follow-up period, 14 CHF patients (25.9%) were readmitted for severe HF, but none died. A logistic regression analysis showed that both ROS level and MTP of the lymphocytes were independent predictors (B=7.03, P=0.006; B= - 0.32, P=0.029, respectively) of readmission of CHF patients. CONCLUSIONS: In CHF patients at low risk, MTP and ROS levels of the lymphocytes showed a significant change that is associated with serum NT-proBNP and patient readmission.


Assuntos
Insuficiência Cardíaca/sangue , Linfócitos/metabolismo , Potencial da Membrana Mitocondrial , Readmissão do Paciente , Espécies Reativas de Oxigênio/sangue , Idoso , Doença Crônica , Feminino , Humanos , Linfócitos/patologia , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos
10.
Bull Exp Biol Med ; 161(1): 104-7, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27265129

RESUMO

We studied the effect of inhibition of mitochondrial voltage-dependent anion channels with DIDS on radiosensitivity and mitochondrial status of K562 leukemic cells. The number of apoptotic and necrotic cells, mitochondrial transmembrane potential, and mitochondrial mass were evaluated after irradiation of cells in doses of 4 and 12 Gy in the presence and absence of the inhibitor. Inhibition of mitochondrial voltage-dependent anion channels increased radiosensitivity of K562 cells by 50-70% and decreased both mitochondrial transmembrane potential and mitochondrial mass. Inhibitors of voltage-dependent anion channels are promising agents capable of improving the effectiveness of cancer radiotherapy.


Assuntos
Ácido 4,4'-Di-Isotiocianoestilbeno-2,2'-Dissulfônico/farmacologia , Proteínas de Transporte da Membrana Mitocondrial/antagonistas & inibidores , Tolerância a Radiação/efeitos dos fármacos , Radiossensibilizantes/farmacologia , Canais de Ânion Dependentes de Voltagem/antagonistas & inibidores , Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Células K562 , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo
11.
Bioorg Med Chem Lett ; 25(22): 5250-3, 2015 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-26483197

RESUMO

Here, we report for the first time on two novel water-soluble polyol-methanofullerenes which uncouple respiration and oxidative phosphorylation. A cytofluorimetric JC-1-based ratiometric assay was used to quantify mitochondrial potential Ψm in Yarrowia lipolytica cells exposed to the fullerenes tested. Both methanofullerenes significantly downregulated Ψm, thereby decreasing the subset of cells with high mitochondrial potential compared with intact control cells. The Ψm-low subset of Yarrowia lipolytica cells resulted from methanofullerenes exposure preserved physiological cell size and granularity patterns.


Assuntos
Fulerenos/farmacologia , Desacopladores/farmacologia , Yarrowia/efeitos dos fármacos , Citometria de Fluxo , Potenciais da Membrana , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Fosforilação Oxidativa , Solubilidade , Água , Yarrowia/metabolismo
12.
Asian Pac J Cancer Prev ; 25(1): 351-363, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38285803

RESUMO

OBJECTIVE: Clerodendrum infortunatum L. has long been used in traditional medicine in Sri Lanka for tumours, cancer, and certain skin diseases. The present study aimed to assess the anticancer properties of the aqueous extract of C. infortunatum L. root (AECIR) through the activation of the apoptotic pathway on hepatocellular carcinoma (HepG2) and thus give it a scientific validation. Further, the contribution of polyphenols in antioxidant activity and cell cytotoxicity was investigated. METHODS: Powdered plant material was boiled with water (100°C) to obtained AECIR.  The DPPH assay was used to determine the antioxidant potential. The activity of AECIR on HepG2 and normal rat fibroblast (CC1) cell growth was determined using MTT assay. The morphological changes related to apoptotic pathway was examined by Ethidium Bromide/Acridine Orange (EB/AO), Rhodamine 123 (Rh123) and DNA fragmentation assay. RESULTS: The AECIR demonstrated antioxidant potential with an EC50 of 350.2 ± 1.5 ug/mL for DPPH assay. The HO•, H2O2 and •NO free radical scavenging activity was observed with EC50 of 19.7 ± 2.3, 11.7 ± 0.1 and 273.1 ± 0.9 ug/mL, respectively. The antiproliferative effect of AECIR on HepG2 cells was observed in a time and dose dependent manner with an EC50 of 239.1 ± 1.3 µg/mL while CC1 cells showed a nontoxic effect with an EC50 1062.7 ± 3.4 µg/mL after 24hrs treatment. A significant decrease in antioxidant activity (p<0.001) and 90% HepG2 cell viability was observed with polyphenol removed AECIR compared to the polyphenol present AECIR. The EB/AO uptake, depletion of mitochondrial transmembrane potential, and DNA fragmentation assay results revealed that the apoptosis was induced by AECIR. CONCLUSION: The obtained result of the present study demonstrates that the antioxidant potential and antiproliferative activity of AECIR is attributed to the presence of polyphenols. Furthermore, the findings provide the scientific base for anti-cancer potential of AECIR.


Assuntos
Carcinoma Hepatocelular , Clerodendrum , Neoplasias Hepáticas , Animais , Ratos , Humanos , Carcinoma Hepatocelular/tratamento farmacológico , Polifenóis/farmacologia , Antioxidantes/farmacologia , Células Hep G2 , Peróxido de Hidrogênio , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Neoplasias Hepáticas/tratamento farmacológico , Proliferação de Células , Apoptose
13.
J Hepatol ; 59(3): 583-94, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23567086

RESUMO

Inflammation can be either beneficial or detrimental to the liver, depending on multiple factors. Mild (i.e., limited in intensity and destined to resolve) inflammatory responses have indeed been shown to exert consistent hepatoprotective effects, contributing to tissue repair and promoting the re-establishment of homeostasis. Conversely, excessive (i.e., disproportionate in intensity and permanent) inflammation may induce a massive loss of hepatocytes and hence exacerbate the severity of various hepatic conditions, including ischemia-reperfusion injury, systemic metabolic alterations (e.g., obesity, diabetes, non-alcoholic fatty liver disorders), alcoholic hepatitis, intoxication by xenobiotics and infection, de facto being associated with irreversible liver damage, fibrosis, and carcinogenesis. Both liver-resident cells (e.g., Kupffer cells, hepatic stellate cells, sinusoidal endothelial cells) and cells that are recruited in response to injury (e.g., monocytes, macrophages, dendritic cells, natural killer cells) emit pro-inflammatory signals including - but not limited to - cytokines, chemokines, lipid messengers, and reactive oxygen species that contribute to the apoptotic or necrotic demise of hepatocytes. In turn, dying hepatocytes release damage-associated molecular patterns that-upon binding to evolutionary conserved pattern recognition receptors-activate cells of the innate immune system to further stimulate inflammatory responses, hence establishing a highly hepatotoxic feedforward cycle of inflammation and cell death. In this review, we discuss the cellular and molecular mechanisms that account for the most deleterious effect of hepatic inflammation at the cellular level, that is, the initiation of a massive cell death response among hepatocytes.


Assuntos
Morte Celular/fisiologia , Hepatite/patologia , Hepatite/fisiopatologia , Animais , Apoptose , Autofagia , Senescência Celular , Chaperona BiP do Retículo Endoplasmático , Estresse do Retículo Endoplasmático , Humanos , Lipídeos/fisiologia , Fígado/patologia , Fígado/fisiopatologia , Modelos Biológicos , Estresse Oxidativo , Transdução de Sinais/fisiologia , Fator de Necrose Tumoral alfa/fisiologia
14.
Biochem Biophys Res Commun ; 442(1-2): 33-7, 2013 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-24225120

RESUMO

Transmissible gastroenteritis virus (TGEV), an enteropathogenic coronavirus, causes severe lethal watery diarrhea and dehydration in piglets. Previous studies indicate that TGEV infection induces cell apoptosis in host cells. In this study, we investigated the roles and regulation of reactive oxygen species (ROS) in TGEV-activated apoptotic signaling. The results showed that TGEV infection induced ROS accumulation, whereas UV-irradiated TGEV did not promote ROS accumulation. In addition, TGEV infection lowered mitochondrial transmembrane potential in PK-15 cell line, which could be inhibited by ROS scavengers, pyrrolidinedithiocarbamic (PDTC) and N-acetyl-l-cysteine (NAC). Furthermore, the two scavengers significantly inhibited the activation of p38 MAPK and p53 and further blocked apoptosis occurrence through suppressing the TGEV-induced Bcl-2 reduction, Bax redistribution, cytochrome c release and caspase-3 activation. These results suggest that oxidative stress pathway might be a key element in TGEV-induced apoptosis and TGEV pathogenesis.


Assuntos
Apoptose , Gastroenterite Suína Transmissível/metabolismo , Gastroenterite Suína Transmissível/patologia , Espécies Reativas de Oxigênio/metabolismo , Vírus da Gastroenterite Transmissível/metabolismo , Acetilcisteína/farmacologia , Animais , Linhagem Celular , Sequestradores de Radicais Livres/farmacologia , Gastroenterite Suína Transmissível/virologia , Potencial da Membrana Mitocondrial , Estresse Oxidativo , Pirrolidinas/farmacologia , Transdução de Sinais , Suínos , Tiocarbamatos/farmacologia , Proteína Supressora de Tumor p53/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
15.
Bioelectromagnetics ; 34(8): 618-29, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24217848

RESUMO

Biological effects of man-made electromagnetic fields (EMFs) have been studied so far by experimental approaches exposing animals and cell cultures to EMFs. However, the evidence for cell toxicity induced by static magnetic field (SMF) is still uncertain. We investigated the effects produced by the exposure of human SH-SY5Y neuronal-like cells to a uniform magnetic field at intensities of 2.2 mT, which is less than the recommended public exposure limits set by the International Commission on Non-Ionizing Radiation Protection (ICNIRP). A decrease of membrane mitochondrial potential up to 30% was measured after 24 h of exposure to SMF in SH-SY5Y cells, and this effect was associated with reactive oxygen species production increase. Fourier transform infrared spectroscopy (FTIR) analysis showed that exposure to a static magnetic intensity around 2.2 mT changed the secondary structure of cellular proteins and lipid components. The vibration bands relative to the methylene group increased significantly after 4 h of exposure, whereas further exposure up to 24 h produced evident shifts of amide I and II modes and a relative increase in ß-sheet contents with respect to α-helix components. Our study demonstrated that a moderate SMF causes alteration in cell homeostasis, as indicated by FTIR spectroscopy observations of changes in protein structures that are part of cell response to magnetic field exposure.


Assuntos
Campos Magnéticos/efeitos adversos , Neurônios/citologia , Espécies Reativas de Oxigênio/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Linhagem Celular Tumoral , Sobrevivência Celular , Humanos , Potencial da Membrana Mitocondrial , Neurônios/metabolismo , Fatores de Tempo
16.
J Sci Food Agric ; 93(1): 149-56, 2013 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-22696075

RESUMO

BACKGROUND: Lycium barbarum polysaccharide (LBP), isolated with boiling water from the famous Chinese medicinal herb Lycium barbarum fruits, is one of the most important functional constituents in Lycium barbarum. In this study the effects of LBP on cell proliferation, cell cycle and apoptosis in human cervical carcinoma cells (HeLa cells) were investigated. RESULTS: LBP could inhibit the proliferation of HeLa cells by changing cell cycle distribution and inducing apoptosis. In addition, the loss of mitochondrial transmembrane potential (Δψm ) was observed by flow cytometry and the increase of intracellular Ca(2+) concentration was detected by laser scanning confocal microscope in apoptotic cells. At the same time, the nitric oxide content, nitric oxide synthase and inducible nitric oxide synthase activities were also increased. CONCLUSION: The inhibitory effect of LBP on the proliferation of HeLa cells was caused by inducing apoptosis through the mitochondrial pathway. The results showed that LBP can be developed as a potential chemotherapeutic agent candidate against human cervical cancer.


Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Medicamentos de Ervas Chinesas/uso terapêutico , Lycium/química , Fitoterapia , Neoplasias do Colo do Útero/tratamento farmacológico , Antineoplásicos Fitogênicos/farmacologia , Apoptose , Cálcio/metabolismo , Ciclo Celular/efeitos dos fármacos , Proliferação de Células , Medicamentos de Ervas Chinesas/farmacologia , Feminino , Frutas/química , Células HeLa , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Neoplasias do Colo do Útero/metabolismo
17.
Adv Microbiol ; 13(8): 399-419, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37654621

RESUMO

The Helicobacter pylori vacuolating cytotoxin (VacA) is an intracellular, mitochondrial-targeting exotoxin that rapidly causes mitochondrial dysfunction and fragmentation. Although VacA targeting of mitochondria has been reported to alter overall cellular metabolism, there is little known about the consequences of extended exposure to the toxin. Here, we describe studies to address this gap in knowledge, which have revealed that mitochondrial dysfunction and fragmentation are followed by a time-dependent recovery of mitochondrial structure, mitochondrial transmembrane potential, and cellular ATP levels. Cells exposed to VacA also initially demonstrated a reduction in oxidative phosphorylation, as well as increase in compensatory aerobic glycolysis. These metabolic alterations were reversed in cells with limited toxin exposure, congruent with the recovery of mitochondrial transmembrane potential and the absence of cytochrome c release from the mitochondria. Taken together, these results are consistent with a model that mitochondrial structure and function are restored in VacA-intoxicated cells.

18.
Biology (Basel) ; 12(4)2023 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-37106816

RESUMO

Aqueous extracts from Posidonia oceanica's green and brown (beached) leaves and rhizomes were prepared, submitted to phenolic compound and proteomic analysis, and examined for their potential cytotoxic effect on HepG2 liver cancer cells in culture. The chosen endpoints related to survival and death were cell viability and locomotory behavior, cell-cycle analysis, apoptosis and autophagy, mitochondrial membrane polarization, and cell redox state. Here, we show that 24 h exposure to both green-leaf- and rhizome-derived extracts decreased tumor cell number in a dose-response manner, with a mean half maximal inhibitory concentration (IC50) estimated at 83 and 11.5 µg of dry extract/mL, respectively. Exposure to the IC50 of the extracts appeared to inhibit cell motility and long-term cell replicating capacity, with a more pronounced effect exerted by the rhizome-derived preparation. The underlying death-promoting mechanisms identified involved the down-regulation of autophagy, the onset of apoptosis, the decrease in the generation of reactive oxygen species, and the dissipation of mitochondrial transmembrane potential, although, at the molecular level, the two extracts appeared to elicit partially differentiating effects, conceivably due to their diverse composition. In conclusion, P. oceanica extracts merit further investigation to develop novel promising prevention and/or treatment agents, as well as beneficial supplements for the formulation of functional foods and food-packaging material with antioxidant and anticancer properties.

19.
Methods Mol Biol ; 2310: 47-56, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34095997

RESUMO

Mouse embryonic stem cells (mESCs) can be grown in culture, recapitulating the different states of pluripotency of their in vivo counterparts, with notably different metabolic profiles. mESCs in a naïve pluripotent state present an ambivalent metabolism, using both glycolysis and oxidative phosphorylation as energy sources. Here, we describe a method to evaluate the oxidative function of naïve mESCs using the Seahorse Extracellular Flux Analyzer coupled to flow cytometry analysis of mitochondrial transmembrane potential using the TMRM fluorescence probe, thus assessing both oxygen consumption and mitochondrial membrane potential. This may be a useful protocol for understanding how mitochondrial oxidative function and potential of mESCs change in certain circumstances, and how is it related with various pluripotency/differentiation phenotypes.


Assuntos
Metabolismo Energético , Citometria de Fluxo , Potencial da Membrana Mitocondrial , Mitocôndrias/metabolismo , Células-Tronco Embrionárias Murinas/metabolismo , Animais , Fracionamento Celular , Linhagem Celular , Corantes Fluorescentes/química , Camundongos , Consumo de Oxigênio , Fenótipo , Rodaminas/química
20.
Antioxidants (Basel) ; 9(12)2020 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-33260915

RESUMO

This study evaluated the effects of 2 weeks of betaine supplementation on apoptosis, oxidative stress, and aerobic capacity after exhaustive endurance exercise (EEE). A double-blind, crossover, and counterbalanced design was adopted, with 10 healthy male participants asked to consume betaine (1.25 g of betaine mixed with 300 mL of sports beverage, twice per day for 2 weeks) or placebo (300 mL of sports beverage). All participants performed a graded exercise test on a treadmill to determine the maximal oxygen consumption (VO2max) before supplementation and then performed the EEE test at an intensity of 80% VO2max after 2 weeks of supplementation. The time to exhaustion, peak oxygen consumption, maximal heart rate, and average heart rate were recorded during the EEE test. Venous blood samples were drawn before, immediately after, and 3 h after the EEE test to assess apoptosis and the mitochondrial transmembrane potential (MTP) decline of lymphocytes as well as the concentrations of thiobarbituric acid reactive substance and protein carbonyl. The results indicated that lymphocyte apoptosis was significantly higher immediately after and 3 h after EEE than before exercise in participants in the placebo trial. However, lymphocyte apoptosis exhibited no significant differences among the three time points in participants in the betaine trial. Moreover, apoptosis in the betaine trial was significantly lower immediately after and 3 h after exercise compared with the placebo trial. No differences were noted for other variables. Thus, 2 weeks of betaine supplementation can effectively attenuate lymphocyte apoptosis, which is elevated by EEE. However, betaine supplementation exhibited no effects on MTP decline, oxidative stress, or aerobic capacity.

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