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1.
J Appl Oral Sci ; 28: e20190519, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32348444

RESUMO

Natural products have emerged as a rich source of bioactive compounds for adjunctive treatments of many infectious and inflammatory conditions, including periodontitis. Among the monoterpenes with significant biological properties, there is the perillyl alcohol (POH), which can be found in several essential oils and has shown immunomodulatory properties in recent studies, which may be interesting in the treatment of non-neoplastic inflammatory disorders. Objective To determine the antibacterial and immune modulatory activities of the POH. Methodology The minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) of the POH for two significant Gram-negative periodontal pathogens were determined by macrodilution and subculture, respectively. Cell proliferation and cytotoxicity in RAW 264.7 macrophages were determined by Trypan Blue and mitochondrial enzymatic activity assay. The modulation of reactive oxygen species (ROS) was analyzed by flow cytometry and expression of TNF and arginase-1 by real-time PCR. Results The POH was effective against P. gingivalis (ATCC 33277) and F. nucleatum (ATCC 25586) with MIC= MBC=1600 µM. No cytotoxicity up to 100 µM was observed on macrophages. The cell proliferation was inhibited from 48 hours at 100 µM (p<0.05) and 250 µM (p<0.01). The POH increased ROS production at both 10 µM and 100 µM (p<0.05) in unstimulated cells. The PMA-induced ROS production was not affected by POH, whereas 100 µM significantly reduced lipopolysaccharide-induced (LPS-induced) ROS. The expression of TNF was not affected by POH in unstimulated cells or in cells polarized to M1 phenotype, whereas both concentrations of POH reduced (p<0.05) the expression of arginase-1 in M2-polarized macrophages. Conclusion The POH has antibacterial activity against periodontal pathogens and reduced proliferation of murine macrophages without significant cytotoxicity at concentrations up to 100 µM. In addition, the POH reduced the LPS-induced ROS and the expression of arginase-1 in M2-polarized macrophages.


Assuntos
Antibacterianos/farmacologia , Fusobacterium nucleatum/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Monoterpenos/farmacologia , Porphyromonas/efeitos dos fármacos , Espécies Reativas de Oxigênio/análise , Animais , Arginase/análise , Produtos Biológicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Citometria de Fluxo , Fusobacterium nucleatum/crescimento & desenvolvimento , Expressão Gênica , Lipopolissacarídeos/farmacologia , Macrófagos/metabolismo , Camundongos , Testes de Sensibilidade Microbiana , Porphyromonas/crescimento & desenvolvimento , Células RAW 264.7 , Espécies Reativas de Oxigênio/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Reprodutibilidade dos Testes , Fatores de Tempo , Fator de Necrose Tumoral alfa/análise
2.
Einstein (Sao Paulo) ; 18: eAO5022, 2020.
Artigo em Inglês, Português | MEDLINE | ID: mdl-32215468

RESUMO

OBJECTIVE: To evaluate the effects of oxidative stress on insulin signaling in cardiac tissue of obese mice. METHODS: Thirty Swiss mice were equally divided (n=10) into three groups: Control Group, Obese Group, and Obese Group Treated with N-acetylcysteine. After obesity and insulin resistance were established, the obese mice were treated with N-acetylcysteine at a dose of 50mg/kg daily for 15 days via oral gavage. RESULTS: Higher blood glucose levels and nitrite and carbonyl contents, and lower protein levels of glutathione peroxidase and phosphorylated protein kinase B were observed in the obese group when compared with their respective control. On the other hand, treatment with N-acetylcysteine was effective in reducing blood glucose levels and nitrite and carbonyl contents, and significantly increased protein levels of glutathione peroxidase and phosphorylated protein kinase B compared to the Obese Group. CONCLUSION: Obesity and/or a high-lipid diet may result in oxidative stress and insulin resistance in the heart tissue of obese mice, and the use of N-acetylcysteine as a methodological and therapeutic strategy suggested there is a relation between them.


Assuntos
Acetilcisteína/farmacologia , Dieta Hiperlipídica , Depuradores de Radicais Livres/farmacologia , Resistência à Insulina/fisiologia , Miocárdio/metabolismo , Obesidade/metabolismo , Estresse Oxidativo/fisiologia , Animais , Glicemia/análise , Western Blotting , Peso Corporal , Fluoresceínas/análise , Humanos , Masculino , Camundongos , Estresse Oxidativo/efeitos dos fármacos , Carbonilação Proteica , Espécies Reativas de Oxigênio/análise , Valores de Referência , Espectrofotometria
3.
Biochemistry (Mosc) ; 85(2): 205-212, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32093596

RESUMO

Thymoquinone (TQ) exhibits a wide spectrum of biological activities. Most studies on the neurotoxic action of TQ have been carried out in cancer cell lines. Here, we studied the toxic effect of TQ in primary neuronal cultures in vitro. Incubation with 0.04-0.05 mM TQ for 24 h induced the death of cultured cerebellar granule neurons (CGNs) in a dose-dependent manner. Neuronal death was preceded by an increase in the reactive oxygen species (ROS) generation, as demonstrated using CellROX Green and MitoSOX Red. Confocal and electron microscopy showed that incubation with 0.05 mM TQ for 5 h induced changes in the intracellular localization of mitochondria and mitochondria hypertrophy and cell swelling. The antioxidant N-acetyl-L-cysteine (2 mM) protected CGNs from the toxic action of TQ. Taken together, these facts suggest that TQ is toxic for normal neurons, while ROS-induced changes in the mitochondria can be one of the major causes of the TQ-induced neuronal damage and death.


Assuntos
Benzoquinonas/toxicidade , Grânulos Citoplasmáticos/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Animais , Morte Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Grânulos Citoplasmáticos/metabolismo , Relação Dose-Resposta a Droga , Mitocôndrias/metabolismo , Neurônios/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/análise , Espécies Reativas de Oxigênio/metabolismo , Relação Estrutura-Atividade
4.
Phytopathology ; 110(2): 297-308, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31483224

RESUMO

The reduction-oxidation (redox) environment of the phytobiome (i.e., the plant-microbe interface) can strongly influence the outcome of the interaction between microbial pathogens, commensals, and their host. We describe a noninvasive method using a bacterial bioreporter that responds to reactive oxygen species and redox-active chemicals to compare microenvironments perceived by microbes during their initial encounter of the plant surface. A redox-sensitive variant of green fluorescent protein (roGFP2), responsive to changes in intracellular levels of reduced and oxidized glutathione, was expressed under the constitutive SP6 and fruR promoters in the epiphytic bacterium Pantoea eucalypti 299R (Pe299R/roGFP2). Analyses of Pe299R/roGFP2 cells by ratiometric fluorometry showed concentration-dependent responses to several redox active chemicals, including hydrogen peroxide (H2O2), dithiothreitol (DTT), and menadione. Changes in intracellular redox were detected within 5 min of addition of the chemical to Pe299R/roGFP2 cells, with approximate detection limits of 25 and 6 µM for oxidation by H2O2 and menadione, respectively, and 10 µM for reduction by DTT. Caffeic acid, chlorogenic acid, and ascorbic acid mitigated the H2O2-induced oxidation of the roGFP2 bioreporter. Aqueous washes of peach and rose flower petals from young blossoms created a lower redox state in the roGFP2 bioreporter than washes from fully mature blossoms. The bioreporter also detected differences in surface washes from peach fruit at different stages of maturity and between wounded and nonwounded sites. The Pe299R/roGFP2 reporter rapidly assesses differences in redox microenvironments and provides a noninvasive tool that may complement traditional redox-sensitive chromophores and chemical analyses of cell extracts.


Assuntos
Técnicas Biossensoriais , Monitoramento Ambiental , Pantoea , Plantas , Técnicas Biossensoriais/métodos , Monitoramento Ambiental/métodos , Expressão Gênica/efeitos dos fármacos , Glutationa/farmacologia , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Peróxido de Hidrogênio/análise , Oxirredução , Pantoea/genética , Pantoea/metabolismo , Plantas/microbiologia , Espécies Reativas de Oxigênio/análise , Propriedades de Superfície , Vitamina K 3/análise
5.
Inorg Chem ; 59(1): 748-758, 2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-31808678

RESUMO

The rational design by the introduction of fluorine into a compound has achieved success in the development of organic anticancer drugs. However, the fluorine effect in metal-based anticancer complexes has rarely been reported. In this contribution, we report the synthesis, characterization, chemical reactivity, and biological activity of a series of half-sandwich zwitterionic iridium(III) complexes containing different substituents in the η5-CpR ring. The molecular structures for complexes Ir1-Ir4 and Ir7 were determined by single-crystal X-ray crystallography techniques. Notably, the asymmetrically substituted fluoro complexes Ir4 and Ir6 in solution show two conformational isomers. These complexes have sufficient stability, exhibit fluorescence emission, and show potent catalytic activity in converting NADH to NAD+. The effect of the substituents in the η5-CpR ring for these zwitterionic complexes on their anticancer activity was systematically investigated. Surprisingly, the presence of fluorinated substituents gives rise to a significant increase in the anticancer activity. The lipophilicity and cellular uptake levels of these complexes appeared to be the primary factors for their cytotoxicity in this system. A microscopic mechanism study showed that the typical complex Ir4 entered A549 cancer cells through an energy-dependent pathway and was mainly located in lysosomes. Furthermore, an increase in ROS level, apoptosis induction, and cell-cycle perturbation together contribute to the anticancer potency of these zwitterionic complexes.


Assuntos
Antineoplásicos/farmacologia , Complexos de Coordenação/farmacologia , Flúor/química , Irídio/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cisplatino/química , Cisplatino/farmacologia , Complexos de Coordenação/síntese química , Complexos de Coordenação/química , Cristalografia por Raios X , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Irídio/química , Modelos Moleculares , Estrutura Molecular , Espécies Reativas de Oxigênio/análise
6.
Eur J Med Chem ; 186: 111895, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31771825

RESUMO

A series of eight alkyl gallium complexes of general formulae [GaMe2(L)] and [Ga(Me)2L] have been synthesised, characterised and their antimicrobial activity against bacteria, cancer cells and Leishmania assessed. All eight complexes are novel, with the solid-state structures of all complexes successfully authenticated by single crystal X-ray diffraction. The dimethyl complexes all adopt a four-coordinate tetrahedral confirmation, while the monomethyl complexes are five-coordinate trigonal bipyramidal. All complexes were screened for their anti-bacterial activity either by solution state diffusion, or a solid-state stab test. The five soluble complexes underwent testing against two differing mammalian cell controls, with excellent selectivity observed against COS-7 cells, with an IC50 range of 88.5 µM to ≥100 µM. Each soluble complex was also tested for their anti-cancer capabilities, with no significant activity observed. Excellent activity was exhibited against the protozoan parasite Leishmania major (strain: V121) in both the promastigote and amastigote forms, with IC50 values ranging from 1.11 µM-13.4 µM for their anti-promastigote activity and % infection values of 3.5% ± 0.65-11.5% ± 0.65 for the more clinically relevant amastigote. Selectivity indices for each were found to be in the ranges of 6.61-64.7, with significant selectivity noted for two of the complexes. At minimum, the gallium complexes show a 3-fold enhancement in activity towards the Leishmaniaamastigotes over the parent quinolinols alone.


Assuntos
Antiprotozoários/farmacologia , Complexos de Coordenação/farmacologia , Gálio/farmacologia , Hidroxiquinolinas/farmacologia , Leishmania major/efeitos dos fármacos , Animais , Antiprotozoários/síntese química , Antiprotozoários/química , Células COS , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Complexos de Coordenação/síntese química , Complexos de Coordenação/química , Relação Dose-Resposta a Droga , Gálio/química , Células HeLa , Humanos , Hidroxiquinolinas/química , Leishmania major/metabolismo , Camundongos , Estrutura Molecular , Testes de Sensibilidade Parasitária , Espécies Reativas de Oxigênio/análise , Relação Estrutura-Atividade
7.
Chem Commun (Camb) ; 55(100): 15097-15100, 2019 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-31782429

RESUMO

We prepared a nanoprobe through self-assembly of gold nanoclusters (AuNCs) and using FITC-modified hyaluronic acid (HA) for ratiometric sensing of highly reactive oxygen species (hROS). Taking advantage of the aggregation-induced emission (AIE) properties of the self-assembled AuNCs, hROS-responsive cleavage of HA, and the ratiometric signal change of dual-emission, the nanoprobe exhibited excellent performance in imaging hROS in living cells.


Assuntos
Ouro/química , Nanopartículas Metálicas/química , Espécies Reativas de Oxigênio/análise , Espectrometria de Fluorescência/métodos , Animais , Glutationa/química , Lipopolissacarídeos/farmacologia , Macrófagos/citologia , Macrófagos/enzimologia , Macrófagos/metabolismo , Nanopartículas Metálicas/toxicidade , Camundongos , Microscopia de Fluorescência , Células RAW 264.7
8.
Chem Commun (Camb) ; 55(93): 14081-14084, 2019 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-31696872

RESUMO

Cholesterol (CHOL) is an indispensable component of liposomes. Incorporation of 7-dehydrocholesterol (7-DHC) instead of CHOL can efficiently enhance the anticancer activity of photosensitizer-encapsulated liposomes upon irradiation, yielding an IC50 value about half of that of CHOL-based controls. The photo-oxidation of 7-DHC into its endoperoxide form by singlet oxygen may account for the enhanced therapeutic effect, realizing an efficient combination of photodynamic therapy (PDT) and photoactivated chemotherapy.


Assuntos
Antineoplásicos/farmacologia , Desidrocolesteróis/farmacologia , Lipossomos/farmacologia , Fármacos Fotossensibilizantes/farmacologia , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Desidrocolesteróis/química , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Lipossomos/química , Imagem Óptica , Tamanho da Partícula , Fotoquimioterapia , Fármacos Fotossensibilizantes/química , Espécies Reativas de Oxigênio/análise , Espécies Reativas de Oxigênio/metabolismo
9.
Chem Commun (Camb) ; 55(93): 13987-13990, 2019 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-31687673

RESUMO

Polyprodrug-based delivery technique is a fast-growing and effective strategy to improve the therapeutic efficacy of small molecule drugs. We herein developed a robust mitoxantrone (MTO)-based polyprodrug nanoplatform for systemic cisplatin prodrug delivery and combination cancer therapy. Our results show that this nanoplatform can concurrently transport MTO and cisplatin to tumor cells and significantly inhibit tumor growth.


Assuntos
Antineoplásicos/farmacologia , Cisplatino/farmacologia , Sistemas de Liberação de Medicamentos , Mitoxantrona/farmacologia , Nanopartículas/química , Polímeros/farmacologia , Pró-Fármacos/farmacologia , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cisplatino/química , Terapia Combinada , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Mitoxantrona/química , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Imagem Óptica , Tamanho da Partícula , Polímeros/química , Pró-Fármacos/química , Espécies Reativas de Oxigênio/análise , Espécies Reativas de Oxigênio/metabolismo
10.
Chem Commun (Camb) ; 55(90): 13518-13521, 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31608902

RESUMO

A distyryl boron dipyrromethene based photosensitiser substituted with 1,2,4,5-tetrazine and alkyne moieties was prepared. Through site-specific bioorthogonal reactions with the complementary functional tags anchored on the membrane of A431 human epidermoid carcinoma cells, this versatile photosensitiser exhibited enhanced cellular uptake and photocytotoxicity. The bioorthogonal ligation was also demonstrated in tumour-bearing nude mice.


Assuntos
Antineoplásicos/farmacologia , Compostos de Boro/farmacologia , Fotoquimioterapia , Fármacos Fotossensibilizantes/farmacologia , Porfobilinogênio/análogos & derivados , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Compostos de Boro/síntese química , Compostos de Boro/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Camundongos , Camundongos Nus , Estrutura Molecular , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Imagem Óptica , Fármacos Fotossensibilizantes/síntese química , Fármacos Fotossensibilizantes/química , Porfobilinogênio/síntese química , Porfobilinogênio/química , Porfobilinogênio/farmacologia , Espécies Reativas de Oxigênio/análise , Espécies Reativas de Oxigênio/metabolismo , Relação Estrutura-Atividade
11.
Eur J Med Chem ; 182: 111645, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31494472

RESUMO

As our research focus on anticancer drugs, two series of novel derivatives of Flexicaulin A (FA), an ent-kaurene diterpene, condensation with amino acid trifluoroacetate were synthesized, and their anti-proliferative activity against four human cancer cell lines (TE-1, MCF-7, A549 and MGC-803) were evaluated. Compared with FA, the anticancer activity and solubility of most derivatives were significantly improved. Among them, compound 6d had the best activity, and its IC50 value against Esophageal cancer cells (TE-1) was up to 0.75 µM. Subsequent cellular mechanism studies showed that compound 6d could inhibit the proliferation of cancer cells, the formation of cell colonies, and increase the level of ROS on TE-1 cells. In addition, 6d could up-regulate the expressions of SAPK/JNK pathway-associated proteins (p-ASK1, p-MKK4 and p-JNK) and pro-apoptotic proteins (Bak, Bad and Noxa), remarkably increase the ratio of Bax to Bcl-2 and activate Cleaved Caspase-3/9/PARP. These results indicate that compound 6d induces apoptosis through the ROS/JNK/Bcl-2 pathway and holds promising potential as an anti-proliferative agent.


Assuntos
Aminoácidos/farmacologia , Antineoplásicos/farmacologia , Diterpenos de Caurano/farmacologia , Ácido Trifluoracético/farmacologia , Aminoácidos/química , Antineoplásicos/síntese química , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Diterpenos de Caurano/química , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Espécies Reativas de Oxigênio/análise , Espécies Reativas de Oxigênio/metabolismo , Relação Estrutura-Atividade , Ácido Trifluoracético/química , Células Tumorais Cultivadas
12.
Eur J Med Chem ; 182: 111659, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31491611

RESUMO

A series of C-23 modified 23-hydroxybetulinic acid (HBA) derivatives were synthesized and evaluated for their antiproliferative activity against a panel of cancer cell lines (A2780, A375, B16, MCF-7 and HepG2). The biological screening results showed that most of the derivatives exhibited more potent antiproliferative activity than HBA, and compound 6e exhibited the most potent activity with IC50 values of 2.14 µM, 2.89 µM, and 3.97 µM against A2780, B16, and MCF-7 cells, respectively. Further anticancer mechanism studies revealed that compound 6e induced the generation of intracellular reactive oxygen species (ROS) and reduction of mitochondrial membrane potential (MMP) of B16 cells in a dose-dependent manner. Moreover, western blot analysis indicated that compound 6e downregulated the expression of anti-apoptotic protein Bcl-2 and upregulated the expression of proapoptotic protein Bax, activation of caspase 3 to induce cell apoptosis. Meanwhile, compound 6e significantly inhibited the phosphorylation of MEK, ERK, and Akt without affecting the expression of MEK, ERK, and Akt. Furthermore, the in vivo anti-tumor activity of 6e was validated (tumor inhibitory ratio of 68.4% at the dose of 30 mg/kg) in mice with B16 melanoma.


Assuntos
Antineoplásicos/farmacologia , Triterpenos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Estrutura Molecular , Espécies Reativas de Oxigênio/análise , Espécies Reativas de Oxigênio/metabolismo , Relação Estrutura-Atividade , Triterpenos/síntese química , Triterpenos/química , Células Tumorais Cultivadas
13.
Molecules ; 24(18)2019 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-31500271

RESUMO

Garlic and formulations containing allicin are used widely as fungicides in modern agriculture. However, limited reports are available on the allelopathic mechanism of green garlic volatile organic compounds (VOCs) and its component allelochemicals. The aim of this study was to investigate VOCs of green garlic and their effect on scavenging of reactive oxygen species (ROS) in cucumber. In this study, green garlic VOCs were collected by HS-SPME, then analyzed by GS-MS. Their biological activity were verified by bioassays. The results showed that diallyl disulfide (DADS) is the main allelochemical of green garlic VOCs and the DADS content released from green garlic is approximately 0.08 mg/g. On this basis, the allelopathic effects of green garlic VOCs in vivo and 1 mmol/L DADS on scavenging of ROS in cucumber seedlings were further studied. Green garlic VOCs and DADS both reduce superoxide anion and increase the accumulation of hydrogen peroxide of cucumber seedlings. They can also regulate active antioxidant enzymes (SOD, CAT, POD), antioxidant substances (MDA, GSH and ASA) and genes (CscAPX, CsGPX, CsMDAR, CsSOD, CsCAT, CsPOD) responding to oxidative stress in cucumber seedlings.


Assuntos
Compostos Alílicos/farmacologia , Cucumis sativus/metabolismo , Dissulfetos/farmacologia , Alho/química , Espécies Reativas de Oxigênio/análise , Compostos Alílicos/isolamento & purificação , Cucumis sativus/efeitos dos fármacos , Cucumis sativus/genética , Dissulfetos/isolamento & purificação , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Peróxido de Hidrogênio/análise , Estresse Oxidativo/efeitos dos fármacos , Feromônios/isolamento & purificação , Feromônios/farmacologia , Proteínas de Plantas/genética , Plântula/efeitos dos fármacos , Plântula/metabolismo , Superóxidos/análise , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/isolamento & purificação
14.
J Dairy Sci ; 102(11): 10543-10553, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31495631

RESUMO

Zearalenone (ZEA) is a common mycotoxin produced by fungi within the genus Fusarium. However, few studies have examined the direct effects of the toxin on the mammary glands. In the present study, the effects of ZEA treatment on bovine mammary epithelial cells (MAC-T) from dairy cows were investigated. The cells were treated with different concentrations of ZEA to evaluate the effect of the toxin on cell viability, intracellular reactive oxygen species (ROS) concentrations, mitochondrial membrane potential, endoplasmic reticulum (ER) stress, and the expression of apoptosis-related genes. The results indicated that different concentrations (5, 10, 15, 20, 25, 30, 50, 60, or 100 µM) of ZEA were able to inhibit growth of MAC-T cells. After exposing the MAC-T cells to 30 µM ZEA, compared with the control group, ROS levels increased, mitochondrial membrane potential decreased, and mRNA expression of the ER-specific stress-related genes GRP78, HSP70, ATF6, EIF2A, ASK1, and CHOP was upregulated in the ZEA-treated group. Further, we analyzed the increase in apoptotic rate by flow cytometry. At the mRNA level, compared with the control group, the expression of the apoptosis-promoting gene BAX was increased in the ZEA-treated group, the expression of the inhibitory gene BCL2 decreased, and the expression of the gene CASP3 increased. We observed a significant increase in caspase-3 activity in ZEA-treated MAC-T cells. Furthermore, the apoptotic rate of the cells in the ZEA group treated with 4-phenylbutyric acid (ER stress inhibitor) decreased and the mRNA expression levels of ER stress markers GRP78 and CHOP decreased. Compared with the ZEA treatment group, the mRNA expression level of the apoptosis-related gene BAX was decreased and the expression level of BCL2 was increased in the ZEA + 4-phenylbutyric acid cotreatment group. These findings indicate that ZEA-induced ER stress increases apoptosis in MAC-T cells. The treatment of MAC-T cells with ZEA reduced cell viability, increased ROS content, decreased mitochondrial membrane potential, increased ER stress marker expression, and induced apoptosis.


Assuntos
Apoptose/efeitos dos fármacos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Glândulas Mamárias Animais/efeitos dos fármacos , Zearalenona/farmacologia , Animais , Apoptose/genética , Caspase 3/metabolismo , Bovinos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Estresse do Retículo Endoplasmático/genética , Estresse do Retículo Endoplasmático/fisiologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Feminino , Citometria de Fluxo , Expressão Gênica/efeitos dos fármacos , Glândulas Mamárias Animais/citologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Fenilbutiratos/farmacologia , RNA Mensageiro/metabolismo , Espécies Reativas de Oxigênio/análise , Espécies Reativas de Oxigênio/metabolismo , Reação em Cadeia da Polimerase em Tempo Real
15.
Eur J Med Chem ; 182: 111596, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31419776

RESUMO

Facing the complexity of Alzheimer's disease (AD), it is now currently admitted that a therapeutic pleiotropic intervention is needed to alter its progression. Among the major hallmarks of the disease, the amyloid pathology and the oxidative stress are closely related. We propose in this study to develop original Multi-Target Directed Ligands (MTDL) able to impact at the same time Aß protein accumulation and toxicity of Reactive Oxygen Species (ROS) in neuronal cells. Such MTDL were obtained by linking on a central piperidine two scaffolds of interest: a typical aminochlorobenzophenone present in numerous 5-HT4R agonists, and diverse antioxidant chemotypes. Interestingly, the most active compound 9g possesses a Ki of 12.7 nM towards 5-HT4R and an antioxidant activity in vitro and in cellulo.


Assuntos
Antioxidantes/farmacologia , Receptores 5-HT4 de Serotonina/metabolismo , Agonistas do Receptor 5-HT4 de Serotonina/farmacologia , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Animais , Antioxidantes/síntese química , Antioxidantes/química , Compostos de Bifenilo/antagonistas & inibidores , Compostos de Bifenilo/metabolismo , Células COS , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Ligantes , Estrutura Molecular , Picratos/antagonistas & inibidores , Picratos/metabolismo , Espécies Reativas de Oxigênio/análise , Espécies Reativas de Oxigênio/metabolismo , Agonistas do Receptor 5-HT4 de Serotonina/síntese química , Agonistas do Receptor 5-HT4 de Serotonina/química , Relação Estrutura-Atividade
16.
J Colloid Interface Sci ; 555: 470-479, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31400539

RESUMO

Ultrasmall silver nanoclusters (Ag NCs) are one of the emerging and highly efficient antibacterial agents, owing to the unique features of sub-2 nm particle size and the high abundance of the active Ag+ species. However, practical applications of Ag NCs in biological environment are often hampered by silver oxidization, which results in particle aggregation and loss of antibacterial activity. In this study, for the first time, we develop a facile method to synthesize highly dispersed Ag NCs decorated mesoporous silica nanoparticles (Ag NC-MSNs) capable of long-term and efficient release of Ag+ ions. This novel Ag NC-MSNs nanocomposite was demonstrated as an effective antibacterial agent against both Gram-positive and Gram-negative pathogenic bacteria. Compared with the counterparts Ag NCs and silver nanoparticles decorated mesoporous silica nanoparticles (Ag NP-MSNs), Ag NC-MSNs exhibit 17-fold and 27-fold enhancement in antibacterial potency, respectively. The homogeneous distribution of ultrasmall Ag NCs in the mesoporous architecture of supporting MSNs matrix is crucial for the controlled release of Ag+ ions, leading to the superior broad-spectrum antimicrobial activity. Moreover, the cytotoxicity assay indicated that the effective antibacterial concentration of Ag NC-MSNs shows minimum toxicity on mammalian cells. This new Ag nanocomposite developed in this work is promising for practical applications against various microbial infections.


Assuntos
Antibacterianos/farmacologia , Nanopartículas/química , Pseudomonas aeruginosa/efeitos dos fármacos , Dióxido de Silício/farmacologia , Prata/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Antibacterianos/química , Sobrevivência Celular/efeitos dos fármacos , Células HeLa , Humanos , Testes de Sensibilidade Microbiana , Tamanho da Partícula , Porosidade , Espécies Reativas de Oxigênio/análise , Dióxido de Silício/química , Prata/química , Propriedades de Superfície
17.
Intervirology ; 62(3-4): 116-123, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31430757

RESUMO

BACKGROUND: Pseudorabies virus (PRV) infection induces apoptosis in swine cells both in vitro and in vivo; however, the mechanism associated with host-cell signaling has not been studied. This study investigated the role of free radicals caused by cellular oxidative stress after viral infection and examined whether the DNA damage response plays an important role in PRV-induced apoptosis. METHODS: Several apoptosis assays and western blotting confirmed PRV-induced apoptosis. PRV-mediated oxidative stress was evaluated by reactive oxygen species (ROS) assay. RESULTS: Our results showed that PRV caused apoptosis in a porcine kidney cell line, PK15, and induced expressions of proapoptotic Bcl family proteins in a dose- and time-dependent manner. Expressions of specific DNA damage sensors and phosphorylation of histone H2AX were also significantly increased, which subsequently activated the expressions of checkpoint kinase 1/2 and proapoptotic p53. Caffeine, a known DNA damage inhibitor, was found to inhibit caspase-3 activation and protect cells from PRV-induced apoptosis. Additionally, the antioxidant N-acetyl-L-cysteine was shown to prevent the production of cellular ROS, protecting DNA from cleavage. CONCLUSIONS: Our results confirmed that oxidative stress and free radicals arising from PRV infection cause DNA damage, which consequently triggers apoptosis.


Assuntos
Apoptose , Dano ao DNA , Células Epiteliais/virologia , Herpesvirus Suídeo 1/crescimento & desenvolvimento , Interações Hospedeiro-Patógeno , Estresse Oxidativo , Transdução de Sinais , Animais , Western Blotting , Linhagem Celular , Células Epiteliais/patologia , Espécies Reativas de Oxigênio/análise , Suínos
18.
Sensors (Basel) ; 19(16)2019 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-31430858

RESUMO

Due to their ecological relevance, low cost, and easy maintenance, cyanobacteria have been used for bioreporter development. In this study, a battery of cyanobacterial bioreporters has been used to assess the ecotoxicity of four highly used metallic nanoparticles (NPs). The toxicity of these NPs was tested using the bioreporter Nostoc CPB4337 (Anabaena CPB4337). As oxidative stress is a primary toxic mechanism of metallic NPs, cyanobacterial reactive oxygen species (ROS)-detecting bioreporters were used. Metallic NPs release metal ions, which contribute to their toxic effect and the formation of ROS, so a metal-detecting bioreporter was also used to detect the bioavailable metals. The results confirm that ROS production by NPs was due to the NPs per se and not by released free-ions, which in fact were almost undetectable. Although the metal-detecting bioreporter could not detect the dissolved metal ions, it was able to detect the metallic NPs themselves, indicating that this bioreporter may be useful to detect them in the environment. ROS production varied depending on the growth medium or environmental matrices conditions and on the NP type. This work demonstrated the different levels of ROS production by metallic NPs and the importance of nanotoxicology studies in real matrices.


Assuntos
Cianobactérias/efeitos dos fármacos , Poluentes Ambientais/toxicidade , Medições Luminescentes/métodos , Nanopartículas Metálicas/toxicidade , Espécies Reativas de Oxigênio/análise , Cianobactérias/metabolismo , Poluentes Ambientais/química , Nanopartículas Metálicas/química , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Prata/química , Titânio/química
19.
Eur J Med Chem ; 182: 111625, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31442683

RESUMO

The endoplasmic reticulum (ER), as the largest organelle in eukaryotic cells, plays complex but pivotal roles in multiple intracellular metabolic functions, including biosynthesis, sensing, and signal transduction, especially in proteins folding and post-translation modification. The ER is regarded as a promising target for anticancer therapy. Based on previous tumor-targeted photodynamic therapy (PDT), we chemically modified the phthalocyanine-based photosensitizer molecule with the small molecular anticancer-targeting drug erlotinib and the ER-targetable moiety methyl sulfonamide to develop an advanced photosensitizer EB-ER-Pc that can specifically target the subcellular organelle ER of EGFR-overexpressing cancer cells. The in vitro experiments show that the dual-target photosensitizer EB-ER-Pc can generate ROS in situ in the ER of the tumor target region to induce ER stress, upregulate Ca2+ ion level, and decrease mitochondrial membrane potential (MMP) to mediate cancer cells death and ablation. The results suggest that EB-ER-Pc is a promising candidate for effective photodynamic cancer therapy.


Assuntos
Antineoplásicos/farmacologia , Retículo Endoplasmático/efeitos dos fármacos , Receptores ErbB/antagonistas & inibidores , Compostos de Organossilício/farmacologia , Fotoquimioterapia , Fármacos Fotossensibilizantes/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Morte Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Receptores ErbB/metabolismo , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Estrutura Molecular , Compostos de Organossilício/síntese química , Compostos de Organossilício/química , Fármacos Fotossensibilizantes/síntese química , Fármacos Fotossensibilizantes/química , Espécies Reativas de Oxigênio/análise , Espécies Reativas de Oxigênio/metabolismo , Relação Estrutura-Atividade
20.
Drug Des Devel Ther ; 13: 2153-2167, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31308628

RESUMO

Purpose: There is an urgent need for the development of novel, effective, and less toxic drugs to treat leukemia. Antimicrobial peptides (AMPs) have received much more attention as alternative chemotherapeutic agents. This study aimed to examined the cytotoxicity of a novel AMP myristoly-CM4 against chronic myeloid leukemia cells (K562/MDR) and acute lymphocytic leukemia cells (Jurkat), and further investigated its selectivity to clarify the cytotoxic mechanism. Materials and methods: In this study, the cytotoxicity and selectivity of myristoly-CM4 against K562/MDR and Jurkat cells were assessed in vitro, and the anticancer mechanism responsible for its cytotoxicity and selectivity was further investigated. Results: Myristoly-CM4 was cytotoxic to these leukemia cell lines (IC50 2-4 µM) and was less cytotoxic to normal cells (HEK-293, L02 cells, peripheral blood mononuclear cells, and erythrocytes). Myristoyl-CM4 had stronger affinity to K562/MDR and Jurkat cells than to normal cells, while the contents of phosphatidylserine and sialic acids on the cell surfaces of K562/MDR and Jurkat cells were significantly higher than that of HEK293 cells. The myristoyl group effectively mediated the internalization of myristoyl-CM4 to leukemia cells. After internalization, myristoyl-CM4 could target mitochondria and affected mitochondrial function, including disruption of Δψm, increasing the accumulation of ROS, increasing the Bax/Bcl-2 ratio, activating caspase 9 and 3, and PARP to induce mitochondria-dependent apoptosis in both K562/MDR and Jurkat cells. Myristoyl-CM4 also induced K562/MDR cell necrosis by directive membrane disruption, and significantly decreased the level of P-glycoprotein in K562/MDR cells. Conclusion: These results suggested that myristoyl-CM4 showed selective cytotoxicity to leukemia K562/MDR and Jurkat cells by apoptosis and/or necrosis pathway. Myristoyl-CM4, thus, appears to be a promising candidate for leukemia treatment, including multidrug-resistant leukemia.


Assuntos
Peptídeos Catiônicos Antimicrobianos/química , Apoptose/efeitos dos fármacos , Leucemia/patologia , Necrose/tratamento farmacológico , Peptídeos Catiônicos Antimicrobianos/síntese química , Peptídeos Catiônicos Antimicrobianos/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Células HEK293 , Humanos , Células Jurkat , Células K562 , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Espécies Reativas de Oxigênio/análise , Espécies Reativas de Oxigênio/metabolismo , Relação Estrutura-Atividade
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