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1.
J Agric Food Chem ; 67(41): 11428-11435, 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31589037

RESUMO

Diosgenin and diosgenyl saponins as the major bioactive compounds isolated from dietary fenugreek seeds, yam roots, etc. possessed strong antitumor effects. To understand their detailed antitumor mechanisms, a fluorophore-appended derivative of diosgenin [Glc/CNHphth-diosgenin (GND)] was synthesized, starting from diosgenin and glucosamine hydrochloride in overall yields of 7-12% over 7-10 steps. Co-localization of GND with organelle-specific stains, transmission electron microscopy, and relative protein analyses demonstrated that GND crossed the plasma membrane through organic anion-transporting polypeptide 1B1 and distributed in the endoplasmic reticulum (ER), lysosome, and mitochondria. In this process, GND induced ER swelling, mitochondrial damage, and autophagosome and upregulating IRE-1α to induce autophagy and apoptosis. Furthermore, autophagy inhibitor chloroquine delayed the appearance of cleaved poly(ADP-ribose) polymerase and inhibited cleaved caspase 8, which indicated that GND induced autophagy to activate caspase-8-dependent apoptosis. These observations suggested that diosgenyl saponin was a potent anticancer agent that elicited ER stress and mitochondria-mediated apoptotic pathways in liver cancer.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Autofagia/efeitos dos fármacos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Neoplasias Hepáticas/fisiopatologia , Extratos Vegetais/farmacologia , Saponinas/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Retículo Endoplasmático/efeitos dos fármacos , Retículo Endoplasmático/genética , Retículo Endoplasmático/metabolismo , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Lisossomos/efeitos dos fármacos , Lisossomos/genética , Lisossomos/metabolismo , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/genética , Mitocôndrias/metabolismo , Transportadores de Ânions Orgânicos/genética , Transportadores de Ânions Orgânicos/metabolismo
2.
Int J Nanomedicine ; 14: 7003-7016, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31564862

RESUMO

Background: Yttria-stabilized zirconia (Y2O3/ZrO2) nanoparticles are one of the important nanoparticles extensively used in manufacturing of plastics, textiles, catalyst, etc. Still, the cytotoxic and apoptotic effects of yttria-stabilized zirconia nanoparticles have not been well identified on human skin keratinocyte (HaCaT) cells. Therefore, in this study, we have designed to examine the cytotoxic potential of yttria-stabilized zirconia nanoparticles in HaCaT cells. Methods: Prior to treatment, the yttria-stabilized zirconia nanoparticles were characterized by using different advanced instruments viz. dynamic light scattering (DLS), scanning electron microscope (SEM) and transmission electron microscope (TEM). Cell viability of HaCaT cells was measured by using MTS and NRU assays and viability of cells was reduced in a dose- and time-dependent manner. Results: Reduction in the viability of cells was correlated with the rise of reactive oxygen species generation, increased caspase-3, mitochondria membrane potential and evidence of DNA strand breakage. These were consistent with the possibility that mitochondria damage can play a significant role in the cytotoxic response. Moreover, the activity of oxidative enzymes such as lipid peroxide (LPO) was increased and glutathione was reduced in HaCaT cells exposed with yttria-stabilized zirconia nanoparticles. It is also important to indicate that HaCaT cells appear to be more susceptible to yttria-stabilized zirconia nanoparticles exposure after 24 hrs. Conclusion: This result provides a dose- and time-dependent apoptosis and genotoxicity of yttria-stabilized zirconia nanoparticles in HaCaT cells.


Assuntos
Apoptose , Dano ao DNA , Células Epiteliais/citologia , Nanopartículas Metálicas/química , Pele/citologia , Ítrio/química , Zircônio/química , Acetilcisteína/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular , Forma Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Quebras de DNA de Cadeia Dupla/efeitos dos fármacos , Fragmentação do DNA/efeitos dos fármacos , Células Epiteliais/metabolismo , Glutationa/metabolismo , Humanos , Membranas Intracelulares/efeitos dos fármacos , Membranas Intracelulares/metabolismo , Lisossomos/efeitos dos fármacos , Lisossomos/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Nanopartículas Metálicas/ultraestrutura , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo
3.
Aquat Toxicol ; 215: 105266, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31401474

RESUMO

The persistent pollutants polybrominated diphenyl ethers (PBDEs) have been demonstrated to produce several negative effects on marine organisms. Although Mytilus galloprovincialis was extensively studied as model system, the effects of PBDEs on the innate immune system of mussels remains unclear. In this study, except for the control treatment, specimens of M. galloprovincialis were fed with microalgae treated with increasing concentrations of PBDEs (maximum level 100 ng L-1 of BDE-47 per day). BDE-47 treatment was maintained for 15 days and then the animals were fed with the same control diet, without contaminants, for 15 days. Samples of haemolymph (HL) were obtained at T0, T15 and T30 days of the experiment to evaluate different parameters related to immunity, such as neutral red retention time, and peroxidase, protease, antiprotease, lysozyme and bactericidal activities. BDE-47 exposure for 15 days affected both the stability of haemocytes and humoral parameters. In addition, the obtained results indicated that, at 30 days, after 15 days of culture without contaminant, the immune parameters were still affected, as some of them did not return to the basal levels, and others remained stimulated. Overall the results indicate that BDE-47 exposures at environmentally realistic levels may affect various aspects of immune function in M. galloprovincialis, acting as stressor that can compromise the general welfare.


Assuntos
Exposição Ambiental , Éteres Difenil Halogenados/toxicidade , Mytilus/imunologia , Animais , Antibacterianos/farmacologia , Comportamento Alimentar/efeitos dos fármacos , Hemócitos/efeitos dos fármacos , Hemócitos/metabolismo , Hemolinfa/efeitos dos fármacos , Hemolinfa/metabolismo , Hemolinfa/microbiologia , Membranas Intracelulares/efeitos dos fármacos , Membranas Intracelulares/metabolismo , Lisossomos/efeitos dos fármacos , Lisossomos/metabolismo , Microalgas/fisiologia , Mytilus/efeitos dos fármacos , Mytilus/microbiologia , Peptídeo Hidrolases/metabolismo , Análise de Sobrevida , Poluentes Químicos da Água/toxicidade
4.
Eur J Med Chem ; 181: 111599, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31408807

RESUMO

In this work, five naphthalimide-modified half-sandwich iridium and ruthenium complexes ([(η5-Cpx)Ir(NˆN)Cl]PF6, [(η6-p-cym)Ru(NˆN)Cl]PF6) have been presented. The anticancer activities of the complexes against various cancer cell lines were investigated, among them, complexes 2 and 4 showed better anticancer activity than cisplatin, and their anticancer activity is better than complex 5 without fluorophore. In addition, a series of biological tests of complex 2 were performed using flow cytometry, the results indicated that the complex could induce cell death in a variety of ways. By changing of the ligands, the complexes exhibited different photophysical properties, and the mechanism of action of the complexes entering the cell and inducing apoptosis are different. Moreover, complex 2 successfully targeted mitochondria, while complex 4 targeted lysosomes, causing mitochondrial damage and lysosomal damage to induce apoptosis. Excitingly, complex 2 has good antimetastatic ability to cancer cells. Furthermore, complexes 2 and 4 did not have a significant effect on the NADH binding reaction, but they had a moderate binding ability to BSA.


Assuntos
Antineoplásicos/farmacologia , Complexos de Coordenação/farmacologia , Irídio/farmacologia , Naftalimidas/farmacologia , Rutênio/farmacologia , Antineoplásicos/química , Linhagem Celular Tumoral , Complexos de Coordenação/química , Ensaios de Seleção de Medicamentos Antitumorais , Corantes Fluorescentes/química , Corantes Fluorescentes/farmacologia , Humanos , Irídio/química , Lisossomos/efeitos dos fármacos , Lisossomos/patologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/patologia , Naftalimidas/química , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Rutênio/química
5.
Ecotoxicol Environ Saf ; 183: 109512, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31398584

RESUMO

Azadirachtin, a botanical insecticide with high potential, has been widely used in pest control. Azadirachtin has shown strong biological activity against Bactrocera dorsalis in toxicological reports, but its mechanism remains unclear. This study finds that azadirachtin A inhibits the growth and development of Bactrocera dorsalis larvae. The larval weights and body sizes of the azadirachtin-treated group were significantly less than those of the control group in a concentration-dependent manner. Further, pathological sections revealed that azadirachtin destroyed the midgut cell structure and intestinal walls, while TUNEL staining showed that azadirachtin could induce apoptosis of midgut cells, and Western blot analysis indicated that Bcl-XL expression was inhibited and cytochrome c (CytC) released into the cytoplasm. The results also imply azadirachtin-induced structural alterations in the Bactrocera dorsalis larvae midgut by activation of apoptosis. RNA-seq analysis of midgut cells found that 482 and 708 unique genes were upregulated and downregulated, respectively. These differentially expressed genes (DEGs) were enriched in apoptotic and lysosomal signaling pathways and included 26 genes of the cathepsin family. qRT-PCR verified the expression patterns of some DEGs, indicating that Cathepsin F was upregulated by 278.47-fold and that Cathepsin L and Cathepsin D were upregulated by 28.06- and 8.97-fold, respectively. Finally, association analysis between DEGs and DEMs (differentially expressed metabolites) revealed that azadirachtin significantly reduced the digestion and absorption of carbohydrates, proteins, fats, vitamins and minerals in the midgut. In conclusion, azadirachtin induces the release of cathepsin from lysosomes, causing apoptosis in the midgut. Ultimately, this leads to reduced digestion and absorption of nutrient metabolites in the midgut and inhibition of the growth and development of Bactrocera dorsalis larvae.


Assuntos
Catepsinas/metabolismo , Inseticidas/toxicidade , Intestinos/efeitos dos fármacos , Larva/efeitos dos fármacos , Limoninas/toxicidade , Tephritidae/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Intestinos/patologia , Larva/crescimento & desenvolvimento , Larva/metabolismo , Lisossomos/efeitos dos fármacos , Lisossomos/metabolismo , Lisossomos/patologia , Transdução de Sinais , Tephritidae/metabolismo
6.
Ecotoxicol Environ Saf ; 183: 109492, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31421534

RESUMO

Bisphenol A (BPA) is an artificial xenoestrogen widely used in consumer products containing polycarbonate plastics and epoxy resins. Exposure to BPA occurs through various channels, including ingestion of contaminated food and water. Autophagy is an important catabolic pathway that plays an important role in liver lipid metabolism. Evidence suggests that BPA exposure causes abnormal lipid droplet accumulation in liver, but the mechanism remains unknown. Here, we investigate the function of BPA in lipid metabolism and autophagy. BPA exposure increases lipid droplet and ROS accumulation which is accompanied by a defect in the fusion of the autophagosome to the lysosome. BPA exposure decreases the translocation of Stx17 to lysosome resulting in the autophagogome-lysosome fusion defect. There is no defect in the formation of the autophagosome indicated by increased LC3-II, p62 level, GFP/mRFP-LC3 ratios and decreased colocalization between LAMP2 with LC3. Mechanistically, BPA exposure reduces autophagy SNARE complex formation. Promoting autophagy by autophagy inducer (Torin2) partially reverses lipid droplet accumulation caused by BPA exposure. In summary, our results demonstrate BPA exposure inhibits autophagy resulting in decreased lipid droplet degradation and increased ROS levels. These results also provide a novel implication between autophagosome-lysosome fusion.


Assuntos
Autofagossomos/efeitos dos fármacos , Compostos Benzidrílicos/toxicidade , Poluentes Ambientais/toxicidade , Gotículas Lipídicas/efeitos dos fármacos , Lisossomos/efeitos dos fármacos , Fenóis/toxicidade , Animais , Autofagossomos/metabolismo , Autofagia/efeitos dos fármacos , Linhagem Celular , Células HEK293 , Células HeLa , Humanos , Gotículas Lipídicas/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Lisossomos/metabolismo , Camundongos , Naftiridinas/farmacologia , Proteínas Qa-SNARE/metabolismo , Espécies Reativas de Oxigênio/metabolismo
7.
Int J Nanomedicine ; 14: 4867-4880, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31308663

RESUMO

Background: The demand for an effective vaccine delivery system that drives a suitable immune response is increasing. The oxidized carbon nanosphere (OCN), a negatively charged carbon nanoparticle, has the potential to fulfill this requirement because it can efficiently deliver macromolecules into cells and allows endosomal leakage. However, fundamental insights into how OCNs are taken up by antigen-presenting cells, and the intracellular behavior of delivered molecules is lacking. Furthermore, how immune responses are stimulated by OCN-mediated delivery has not been investigated. Purpose: In this study, the model protein antigen ovalbumin (OVA) was used to investigate the uptake mechanism and intracellular fate of OCN-mediated delivery of protein in macrophages. Moreover, the immune response triggered by OVA delivered by OCNs was characterized. Methods: Bone-marrow-derived macrophages (BMDMs) from mice were used to study antigen uptake and intracellular trafficking. Mice were immunized using OCN-OVA combined with known adjuvants, and the specific immune response was measured. Results: OCNs showed no cytotoxicity against BMDMs. OCN-mediated delivery of OVA into BMDMs was partially temperature independent process. Using specific inhibitors, it was revealed that intracellular delivery of OCN-OVA does not rely on phagocytosis or the clathrin- and lipid raft/caveolae-mediated pathways. Delivered OVA was found to colocalize with compartments containing MHC class I, but not with early endosomes, lysosomes, and autophagosomes. Immunization of OVA using OCNs in combination with the known adjuvant monophosphoryl lipid A specifically enhanced interferon gamma (IFNγ)- and granzyme B-producing cytotoxic T cells (CTLs). Conclusion: OCNs effectively delivered protein antigens into macrophages that localized with compartments containing MHC class I partially by the temperature independent, but not clathrin- and lipid raft/caveolae-mediated pathways. Increased CD8+ T-cell activity was induced by OCN-delivered antigens, suggesting antigen processing toward antigen presentation for CTLs. Taken together, OCNs are a potential protein antigen delivery system that stimulates the cell-mediated immune response.


Assuntos
Antígenos/administração & dosagem , Carbono/química , Sistemas de Liberação de Medicamentos , Imunidade Celular , Nanopartículas/química , Adjuvantes Imunológicos/farmacologia , Animais , Antígenos/imunologia , Autofagossomos/efeitos dos fármacos , Autofagossomos/metabolismo , Linhagem Celular , Endocitose/efeitos dos fármacos , Endossomos/efeitos dos fármacos , Endossomos/metabolismo , Feminino , Imunidade Celular/efeitos dos fármacos , Cinética , Lisossomos/efeitos dos fármacos , Lisossomos/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos Endogâmicos BALB C , Nanopartículas/toxicidade , Oxirredução , Linfócitos T Citotóxicos/efeitos dos fármacos , Linfócitos T Citotóxicos/imunologia
8.
Artigo em Chinês | MEDLINE | ID: mdl-31177709

RESUMO

Objective: To investigate the role of lysosomes in manganese-induced toxicity in human neuroblastoma SK-N-SH cells. Methods: SK-N-SH cells were treated with MnCl(2) at doses of 0.062 5, 0.125, 0.25, 0.5, 1.0, 2.0 and 4.0 mmol/L for 24 h, and the cell viability was detected by MTT assay. Cells were treated with MnCl(2) at doses of 0.125, 0.25, 0.5 and 1.0mmol/L for 24 h, and lysosomes labeled with lysotracker red were observed by laser confocal microscopy, the expression levels of LAMP1 and CTSD were detected by western blot, and CTSD activity was detected by Cathepsin D Activity Fluorometric Assay Kit. Results: Compared with the control group, the survival rates of SK-N-SH cells were decreased significantly in the 0.5-4.0 mmol/L MnCl(2) treatment groups (P<0.01) , the relative fluorescence intensities of 0.5 and 1.0 mmol/L MnCl(2) treatment groups were increased (P<0.01) . Compared with the control group, the 0.125-0.5 mmol/L MnCl(2) treatment groups had significant increase in the the expression of LAMP1 (P<0.01) . Compared with the control group, the expression of m-CTSD was significantly increased at the does of 0.125-0.25 mmol/L MnCl(2), while it was decreased at the does of 1.0 mmol/L (P<0.01) . Otherwise, it wasn't observed significant difference of the activity of CTSD between different MnCl(2) treatment groups. Conclusion: MnCl(2) could cause cytotoxicity in SK-N-SH cells. Lysosomes may play a normal function at low doses of manganese, but they may be damaged at high doses of manganese. As an organelle that can degradate substrates in autophagy, lysosomes participate in the neurotoxic mechanism of manganese.


Assuntos
Intoxicação por Manganês , Manganês , Apoptose , Linhagem Celular Tumoral , Humanos , Lisossomos/efeitos dos fármacos , Manganês/toxicidade
9.
Toxicol Lett ; 313: 60-65, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31226396

RESUMO

The use of waterpipes in the United States is increasing in a largely unregulated market. The shisha smoked in a waterpipe is a complex matrix of tobacco, flavorings, and humectant with smoke generated by an external heat source. This study explored the relationship between shisha components and the particulate matter size distributions and toxicity of smoke generated with heating. Standard waterpipe puff topography of charcoal- or electronic- heated whole shisha and shisha components generated smoke particulate matter that was characterized using a TSI Engine Exhaust Particle Sizer. Relative toxicity of the whole smoke was determined via measurement of lysosomal integrity and measures of membrane integrity following acute exposure of type II alveolar cells at the air-liquid interface. All waterpipe aerosols exhibited a unimodal particle size distribution, the peak and concentration of which varied depending upon the shisha components present. Acute exposure to charcoal-heated whole shisha, flavoring syrup, or humectant smoke, or electronic-heated whole shisha smoke caused significant alveolar cell damage and death, indicating neither tobacco nor charcoal are needed for these cytotoxic effects to occur.


Assuntos
Células Epiteliais Alveolares/efeitos dos fármacos , Carvão Vegetal/toxicidade , Aromatizantes/análise , Higroscópicos/toxicidade , Fumaça/efeitos adversos , Tabaco para Cachimbos de Água/toxicidade , Fumar Cachimbo de Água/efeitos adversos , Aerossóis , Células Epiteliais Alveolares/metabolismo , Células Epiteliais Alveolares/patologia , Animais , Morte Celular/efeitos dos fármacos , Linhagem Celular , Carvão Vegetal/análise , Aromatizantes/efeitos adversos , Higroscópicos/análise , Lisossomos/efeitos dos fármacos , Lisossomos/metabolismo , Lisossomos/patologia , Tamanho da Partícula , Ratos , Medição de Risco , Fumaça/análise , Tabaco para Cachimbos de Água/análise
10.
Cell Mol Biol Lett ; 24: 33, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31160892

RESUMO

Background: Induction of lysosomal function and autophagy is regarded as an adaptive mechanism in response to cellular stress. The transcription factor EB (TFEB) has been identified as a master regulator of lysosomal function and autophagy. TFEB is a member of the microphthalmia family of bHLH-LZ transcription factors that includes other members such as micropthalmia-associated transcription factor (MITF), TFE3, and TFEC. TFEB controls lysosome biogenesis and autophagy by upregulation of a family of genes belonging to the Coordinated Lysosomal Expression and Regulation (CLEAR) network. Here, we investigated the expression of TFEB in cells subjected to nutrient deprivation and lysosomal stress. We studied transcriptional induction of TFEB-regulated genes in response to nutrient deprivation and lysosomal stress in retinal pigment epithelial (RPE) cells. Furthermore, we also investigated the induction of autophagy and lysosomal genes upon overexpression of constitutively active form of TFEB. Methods: Expression of TFEB and MITF protein levels were evaluated in cells subjected to prolonged periods of nutrient deprivation. mRNA levels of the CLEAR network genes was measured by quantitative real time PCR (qRT-PCR) analysis in cells deprived of nutrients, treated with ammonium chloride and upon overexpression of constitutively active TFEB. Immunostaining with LC3 antibody was used to measure autophagy flux. Labeling with lysoTracker dye was used to assess lysosomes. Results: Our results show that nutrient deprivation increases protein levels of TFEB and MITF in ARPE-19 cells. Nutrient stress induces the expression of lysosomal (LAMP1, CTSD MCOLN1, SGSH) and autophagy (BECN1) genes. Lysosomal stress also increases the expression of lysosomal (ATP6V0A1 and LAMP1) and autophagy (p62 and BECN1) genes. Our results show that overexpression of constitutively active TFEB also induces the expression of CLEAR network genes. Conclusions: Collectively, these observations suggest that nutrient stress induces the protein expression of both MITF and TFEB in ARPE-19 cells. TFEB-regulated transcriptional program plays an important role in adaptive response of cells during both nutrient and lysosomal stress.


Assuntos
Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Células Epiteliais/metabolismo , Lisossomos/metabolismo , Epitélio Pigmentado da Retina/patologia , Estresse Fisiológico , Adulto , Cloreto de Amônio/farmacologia , Animais , Linhagem Celular , Células Epiteliais/efeitos dos fármacos , Redes Reguladoras de Genes/efeitos dos fármacos , Humanos , Lisossomos/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Estresse Fisiológico/efeitos dos fármacos , Transcrição Genética/efeitos dos fármacos
11.
Int J Nanomedicine ; 14: 3503-3516, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31190807

RESUMO

Purpose: The NLRP3 inflammasome activation has been proposed as a common mechanism for some adjuvants to boost the immune system, and cationic liposomes were reported to potentially activate the NLRP3 inflammasome. Herein, we questioned whether the NLRP3 inflammasome-activating cationic liposomes could promote antigen presentation and be applied as an immune adjuvant. In addition, we aimed to investigate the structure effect of lipid on triggering these immune responses. Materials and methods: A series of structurally similar lipids, consisting of arginine (Arg) head group and varied lengths of alkyl chains or spacers in between were used to prepare cationic liposomes. Lipopolysaccharide-primed human or murine macrophages or phorbol 12-myristate 13-acetate-primed THP-1 cells were treated with these liposomes, and interleukin (IL)-1ß secretion was measured to quantify the NLRP3 inflammasome activation. Lysosome rupture was examined in THP-1 cells by the fluorescence loss of acridine orange, a lysosome dye. Further, chicken ovalbumin (OVA) was loaded on the liposome surface and applied to murine bone marrow-derived dendritic cells (BMDCs), which activate OT-I and OT-II lymphocytes upon major histocompatibility complex (MHC) class I- and class II-mediated antigen presentation, respectively. OT-I and OT-II cell division and IL-2 secretion were measured to evaluate the antigen presentation efficiency. The expressions of MHC molecules and co-stimulatory molecules ie, CD80, CD86, and CD40 on BMDCs were investigated by flow cytometry. Results: All the liposomes showed size distributions of 80-200 nm and zeta potentials of around 50 mV. A3C14 liposomes, consisting of Arg-C3-Glu2C14 lipids induced the most potent lysosome rupture and NLRP3 inflammasome activation. OVA-A3C14 also exhibited the most potent MHC class I- and class II-mediated antigen presentation in BMDCs without interfering MHC and co-stimulatory molecules. Conclusion: The hydrophobic moieties of arginine-based liposomes are crucial in stimulating innate immune cells. A3C14 liposomes were non-immunogenic but strongly activated innate immune cells and promoted antigen presentation, and therefore can be applied as immune adjuvants.


Assuntos
Apresentação do Antígeno/efeitos dos fármacos , Arginina/farmacologia , Células Dendríticas/imunologia , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Animais , Cátions , Células Dendríticas/efeitos dos fármacos , Feminino , Antígenos de Histocompatibilidade/metabolismo , Humanos , Lipídeos/química , Lipopolissacarídeos/farmacologia , Lipossomos , Lisossomos/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos Endogâmicos C57BL
12.
Food Chem Toxicol ; 131: 110555, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31173818

RESUMO

As a part of the aging process, N-retinylidene-N-retinylethanolamine (A2E) accumulates in the retina to activate autophagy in retinal pigmented epithelial cells. However, the effect of A2E photoactivation on autophagy, which is more clinically relevant, still remains unclear. Here, we investigated the effect of blue light (BL)-activated A2E on autophagy in human retinal pigmented epithelial cells, ARPE-19. A significant increase in LC3-II protein was observed when BL was irradiated on ARPE-19 cells containing A2E. The mammalian target of rapamycin (mTOR) pathway was examined to verify whether autophagy was activated, but no change in AKT, mTOR, and 4EBP phosphorylation was observed. Transcription factor EB (TFEB) target gene expression, which is another pathway involved in autophagy, was also not altered by A2E and BL. However, intracellular p62 protein levels were significantly increased, which represented the inhibition of autophagic flux. To investigate the mechanism of the suppressed autophagic flux, the lysosomal state was observed. After BL irradiation, lysosomal damage was induced in A2E-treated ARPE-19 cells, and this phenomenon was prevented by treatment with the antioxidant, N-acetylcysteine. Our results suggest that A2E photoactivation compromises autophagy in ARPE-19 cells and that reactive oxygen species (ROS) play an important role in this process.


Assuntos
Autofagia/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Epitélio Pigmentado da Retina/efeitos dos fármacos , Retinoides/toxicidade , Acetilcisteína/farmacologia , Linhagem Celular , Humanos , Luz , Lisossomos/efeitos dos fármacos , Proteínas Associadas aos Microtúbulos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Retinoides/efeitos da radiação
13.
Chem Biol Interact ; 307: 147-153, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31071334

RESUMO

The development of novel agrochemical compounds to reduce the use of pesticides with high ecological impact is urgently needed. A complex of Mg with two flavonoids hesperidin and phenanthroline [Mg(hesp)2(phen)], referred to as MgHP, results in high insecticidal activity against urban, agricultural and forest insect pests. In vitro cytotoxicity biomarkers were used to assess the mechanism of action MgHP on fish cells, as this insecticide can reach the aquatic environment and affect its biota. The cytotoxic effects of MgHP were evaluated at different concentrations (0, 0.1, 1, 10, 100 and 1000 ng mL-1) in a zebrafish hepatocyte cell line (ZF-L). Twenty-four hours of exposure to high concentrations (10 and 1000 ng mL-1) of MgHP affected cell confluence and morphology. Mitochondrial activity and lysosomal retention ability decreased as the MgHP concentration was increased. Cell membrane injury, apoptosis, and necrosis were not induced. These results suggested that toxicity to ZF-L cells was due loss of organellar activity caused by MgHP, which may also include activation of an alternative cell death mechanism. However, after 96 h of exposure, the toxic effects of MgHP may be mitigated, even at high concentrations, enabling cellular population recovery. These data provide important information on the mechanism of action of MgHP on hepatocyte fish cells and stimulate analyses to elucidate the cellular responses to MgHP.


Assuntos
Complexos de Coordenação/toxicidade , Inseticidas/toxicidade , Lisossomos/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Complexos de Coordenação/química , Hepatócitos/citologia , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Inseticidas/química , Lisossomos/metabolismo , Mitocôndrias/metabolismo , Poluentes Químicos da Água/toxicidade , Peixe-Zebra
14.
Aquat Toxicol ; 212: 214-221, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31132739

RESUMO

Beta-N-methylamino-L-alanine (BMAA) is a non-proteinogenic amino acid produced by several cyanobacteria species. It is considered to be a potent neurotoxin. Although its neurotoxic effects are well studied, other negative effects of BMAA have not yet been completely elucidated. In the present study, we studied the cytotoxic effects of a wide range of concentrations of BMAA (0.25-2.0 mM) on a stable fish immune cell line (CLC) obtained from carp monocytes. The cells exposed to higher concentrations of BMAA exhibited an altered morphology, changed ATP levels, and reduced proliferation. On the basis of toxic effects of BMAA on lysosomes, mitochondrial dehydrogenases activity, and cell membrane integrity, we determined its cytotoxic concentrations. We also investigated effects of the toxin at non-cytotoxic concentrations on the basic functions of CLC cells. BMAA did not affect the production and release of IL-1ß or phagocytic activity of the cells. However, higher non-toxic BMAA concentrations altered the levels of extracellular and intracellular total proteins compared to those in control cells.


Assuntos
Diamino Aminoácidos/toxicidade , Peixes , Animais , Linhagem Celular , Membrana Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Cianobactérias/química , Ativação Enzimática/efeitos dos fármacos , Lisossomos/efeitos dos fármacos , Oxirredutases/metabolismo , Poluentes Químicos da Água/toxicidade
15.
Chem Commun (Camb) ; 55(45): 6437-6440, 2019 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-31095140

RESUMO

A precise ricin A-chain (RTA) delivery system was constructed by coupling RTA to carbon dots (CDs) with a distinctive capacity for Golgi targeting. The rational design shows efficient internalization and an exact pathway to the cytoplasm for RTA to exert its real toxic action since it could avoid lysosome degradation.


Assuntos
Carbono/química , Sistemas de Liberação de Medicamentos , Complexo de Golgi/química , Pontos Quânticos/química , Ricina/química , Citoplasma/química , Citoplasma/metabolismo , Complexo de Golgi/efeitos dos fármacos , Lisossomos/efeitos dos fármacos , Lisossomos/metabolismo , Ricina/toxicidade
16.
Aquat Toxicol ; 212: 28-36, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31048143

RESUMO

Titanium dioxide nanoparticles (TiO2 NPs) are widely used in various products and inevitably released with different sizes and forms into aquatic environment. The purpose of this study was to assess the differential immune toxicity of TiO2 NPs with size difference on mussel hemocytes using flow cytometry (FCM) assays. Hemocyte parameters, including total hemocyte count (THC), hemocyte mortality (HM), phagocytosis activity (PA), lysosomal content (LC), esterase activity (EA), mitochondrial number (MN), mitochondrial membrane potential (MMP) and reactive oxygen species content (ROS) were evaluated in the mussels Mytilus coruscus exposed to two types of TiO2 NPs (25nm & 100nm: 0.1, 1, 10 mg/L, respectively). In general, size- and concentration-dependent toxicity was pronounced with 25nm-NP and highest concentration (10mg/L) being the most toxic. Alhough a slight recovery from the TiO2 exposure was observed, significant carry-over effects were still detected. These results highlight the importance of differential size effects of metal oxide NPs on toxicity mechanisms in aquatic animals.


Assuntos
Hemócitos/efeitos dos fármacos , Mytilus/efeitos dos fármacos , Nanopartículas/toxicidade , Tamanho da Partícula , Titânio/toxicidade , Análise de Variância , Animais , Contagem de Células , Esterases/metabolismo , Hemócitos/citologia , Lisossomos/efeitos dos fármacos , Nanopartículas/ultraestrutura , Análise de Componente Principal , Poluentes Químicos da Água/toxicidade
17.
Aquat Toxicol ; 211: 46-56, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30946994

RESUMO

The incorporation of silver nanoparticles (AgNPs) in commercial products is increasing rapidly. The consequent release of AgNPs into domestic and industrial wastewater raises environmental concerns due to their anti-microbial properties and toxicity to non-target aquatic organisms. The aim of the present study was to investigate the effects of nanArgen™ (Nanotek S.A.), a AgNP-enabled consumer product, in the marine bivalve Mytilus galloprovincialis. Two environmentally relevant concentrations of nanArgen™ (1 and 10 µg/L) were tested in vivo for 96 h, and Ag was quantified in mussel soft tissue and natural seawater (NSW). nanArgen™ suspensions were characterized via TEM, SEM, EDS, DLS, and UV-vis optical analysis. Several molecular and biochemical responses were investigated in exposed mussels: lysosomal membrane stability by Neutral Red Retention Time (NRRT) assay; micronucleus (MN) frequency in hemocytes; metallothionein (MT) protein content and gene expression (mt10 and mt20); catalase (CAT) and glutathione-S-transferase (GST) activities; malondialdehyde (MDA) accumulation in digestive glands; and efflux activity of ATP-binding cassette transport proteins (ABC) in gill biopsies. SEM, TEM and DLS analyses confirmed the presence of well-defined AgNPs in nanArgen™ which were roughly spherical with an average particle size of approx. 30 ± 10 nm. DLS analysis revealed the formation of AgNP aggregates in nanArgen™ suspension in NSW (Z-average of 547.80 ± 90.23 nm; PDI of 0.044). A significant concentration-dependent accumulation of Ag was found in mussels' whole soft tissue in agreement with a concentration-dependent decrease in NRRT and an increase of MN frequency in hemocytes and GST activities in digestive glands. A significant increase in MDA levels and MT via both molecular and biochemical tests, were also observed but only at the highest nanArgen™ concentration (10 µg/L). No changes were observed in CAT activities. ABC efflux activities in gill biopsies showed a significant decrease (p < 0.05) only at the lowest concentration (1 µg/L). On such basis, nanArgen™ is shown to be able to induce toxicity and Ag accumulation in marine mussels similarly to AgNPs and in short-term exposure conditions at environmentally relevant concentrations. AgNP-enabled products, instead of pristine AgNPs, should be the focus of future ecotoxicity studies in order to address any risks associated to their widespread use, disposal and uncontrolled release into the aquatic environment for non target species.


Assuntos
Nanopartículas Metálicas/toxicidade , Mytilus/efeitos dos fármacos , Prata/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Catalase/metabolismo , Relação Dose-Resposta a Droga , Brânquias/química , Brânquias/efeitos dos fármacos , Brânquias/metabolismo , Hemócitos/efeitos dos fármacos , Hemócitos/patologia , Lisossomos/efeitos dos fármacos , Nanopartículas Metálicas/análise , Metalotioneína/metabolismo , Micronúcleos com Defeito Cromossômico/induzido quimicamente , Mytilus/química , Mytilus/metabolismo , Água do Mar/química , Prata/análise , Poluentes Químicos da Água/análise
18.
Cell Prolif ; 52(3): e12609, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31033054

RESUMO

OBJECTIVES: The genotoxicity of cisplatin towards nuclear DNA is not sufficient to explain the cisplatin resistance of hepatocellular carcinoma (HCC) cells; cisplatin interacts with many organelles, which can influence the sensitivity. Here, we explored the role of mitochondrial-lysosomal crosstalk in the cisplatin resistance of HCC cells. MATERIALS AND METHODS: Huh7 and HepG2 cells were subjected to different treatments. Flow cytometry was conducted to detect mitochondrial reactive oxygen species, mitochondrial mass, lysosomal function, mitochondrial membrane potential and apoptosis. Western blotting was performed to evaluate protein levels. The oxygen consumption rate was measured to evaluate mitochondrial function. RESULTS: Cisplatin activated mitophagy and lysosomal biogenesis, resulting in crosstalk between mitochondria and lysosomes and cisplatin resistance in HCC cells. Furthermore, a combination of cisplatin with the phosphatidylinositol-3-kinase/mammalian target of rapamycin (PI3K/mTOR) inhibitor PKI-402 induced lysosomal membrane permeabilization. This effect changed the role of the lysosome from a protective one to that of a cell death promoter, completely destroying the mitochondrial-lysosomal crosstalk and significantly enhancing the sensitivity of HCC cells to cisplatin. CONCLUSIONS: This is the first evidence of the importance of mitochondrial-lysosomal crosstalk in the cisplatin resistance of HCC cells and of the destruction of this crosstalk by a PI3K/mTOR inhibitor to increase the sensitivity of HCC cells to cisplatin. This mechanism could be developed as a novel target for treatment of HCC in the future.


Assuntos
Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/metabolismo , Cisplatino/farmacologia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/metabolismo , Fosfatidilinositol 3-Quinase/antagonistas & inibidores , Serina-Treonina Quinases TOR/antagonistas & inibidores , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos , Células Hep G2 , Humanos , Lisossomos/efeitos dos fármacos , Lisossomos/metabolismo , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Degradação Mitocondrial/efeitos dos fármacos , Dinâmica Mitocondrial/efeitos dos fármacos , Compostos de Fenilureia/farmacologia , Pirimidinas/farmacologia , Espécies Reativas de Oxigênio/metabolismo
19.
Biotechnol Appl Biochem ; 66(4): 555-563, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30994947

RESUMO

Although cilostazol was proved to have antitumor biological effects, its function in myocardial ischemia and reperfusion (I/R) injury and the underlying mechanisms were not fully illustrated yet. In this study, a rat model of I/R injury was constructed and quantitative real-time PCR, Western blot, and immunofluorescence (IF) assay were performed. Our results showed that cilostazol increased LC3 II/LC3 I ratio, reduced p62 abundance, and promoted the expressions of LAMP1, LAMP2, cathepsin B, and cathepsin D, indicating that cilostazol could activate autophagy and elevated lysosome activation. Following analysis showed that cilostazol enhanced nuclear protein expression of transcription factor EB (TFEB), an important regulator of autophagy-lysosome pathway. Furthermore, CCI-779, an inhibitor of TFEB, could reverse the effects of cilostazol on autophagic activity and lysosome activation. Importantly, cilostazol suppressed I/R injury-induced apoptosis by decreasing the cleavage of caspase 3 and PARP. Enzyme-linked immunosorbent assay showed that cilostazol reduced the serum levels of CTn1 and CK-MB and decreased infract size caused by I/R injuries. Altogether this study suggested that cilostazol protects against I/R injury by regulating autophagy, lysosome, and apoptosis in a rat model of I/R injury. The protective mechanism of cilostazol was partially through increasing the transcriptional activity of TFEB.


Assuntos
Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/biossíntese , Cilostazol/farmacologia , Traumatismo por Reperfusão Miocárdica/genética , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Animais , Autofagia/efeitos dos fármacos , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/antagonistas & inibidores , Modelos Animais de Doenças , Lisossomos/efeitos dos fármacos , Traumatismo por Reperfusão Miocárdica/cirurgia , Ratos , Ratos Sprague-Dawley , Sirolimo/análogos & derivados , Sirolimo/farmacologia
20.
Environ Sci Pollut Res Int ; 26(15): 15354-15372, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30929178

RESUMO

There is increasing evidence that titanium dioxide (TiO2) nanoparticles (NPs) present in water or diet can be taken up by fish and accumulate in internal organs including the liver. However, their further fate in the organ is unknown. This study provides new insights into the interaction, uptake mechanism, intracellular trafficking, and fate of TiO2 NPs (Aeroxide® P25) in fish liver parenchymal cells (RTL-W1) in vitro using high-resolution transmission electron microscopy (TEM) and single particle inductively coupled plasma mass spectrometry (spICP-MS) as complementary analytical techniques. The results demonstrate that following their uptake via caveolae-mediated endocytosis, TiO2 NPs were trafficked through different intracellular compartments including early endosomes, multivesicular bodies, and late endosomes/endo-lysosomes, and eventually concentrated inside multilamellar vesicles. TEM and spICP-MS results provide evidence that uptake was nano-specific. Only NPs/NP agglomerates of a specific size range (~ 30-100 nm) were endocytosed; larger agglomerates were excluded from uptake and remained located in the extracellular space/exposure medium. NP number and mass inside cells increased linearly with time and was associated with an increase in particle diameter suggesting intracellular agglomeration/aggregation. No alterations in the expression of genes regulated by the redox balance-sensitive transcription factor Nrf-2 including superoxide dismutase, glutamyl cysteine ligase, glutathione synthetase, glutathione peroxidase, and glutathione S-transferase were observed. This shows that, despite the high intracellular NP burden (~ 3.9 × 102 ng Ti/mg protein after 24 h) and NP-interaction with mitochondria, cellular redox homeostasis was not significantly affected. This study contributes to a better mechanistic understanding of in vitro particokinetics as well as the potential fate and effects of TiO2 NPs in fish liver cells.


Assuntos
Fígado/efeitos dos fármacos , Nanopartículas/metabolismo , Oncorhynchus mykiss , Titânio/farmacocinética , Poluentes Químicos da Água/farmacocinética , Animais , Linhagem Celular , Ecotoxicologia/métodos , Endocitose/efeitos dos fármacos , Proteínas de Peixes/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Fígado/citologia , Lisossomos/efeitos dos fármacos , Lisossomos/metabolismo , Espectrometria de Massas/métodos , Microscopia Eletrônica de Transmissão , Mitocôndrias Hepáticas/efeitos dos fármacos , Mitocôndrias Hepáticas/metabolismo , Fator 2 Relacionado a NF-E2/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
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