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1.
Chem Biol Interact ; 320: 109022, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32112862

RESUMO

Epithelial mesenchymal transformation plays a crucial role in the metastasis of bladder cancer, which makes bladder cancer difficult to cure. Bladder cancer is the most common malignancy of the urinary system, and distant metastasis is the leading cause of death. Therefore, finding a bioactive drug that can specifically inhibit epithelial mesenchymal transformation may be a new direction for bladder cancer treatment in the future. Thymoquinone (TQ), the major active compound isolated from black seed oil (Nigella sativa), has been reported to exhibit anti-inflammatory and anticancer abilities. TQ can exhibit its antitumor effect by inhibiting the proliferation and metastasis of cancer cells. However, the underlying mechanism of TQ as a tumor inhibitor in bladder cancer remains poorly understood. First, in this research, we demonstrate that TQ can reverse EMT by upregulating epithelial markers, such as E-cadherin, and downregulating mesenchymal markers, such as N-cadherin and vimentin. Furthermore, we demonstrate that TQ can suppress the activation of the Wnt/ß-catenin signaling pathway and inhibit the expression of ß-catenin target genes, such as MYC, Axin-2, MMP7, CyclinD1 and MET, which play crucial roles in EMT and cancer progression. Additionally, we demonstrate that TQ can inhibit the growth of xenografts and restrict the formation of tumor metastatic foci in the lung. Taken together, our findings confirm the antimetastatic effect of TQ in bladder cancer cells for the first time and also provide new evidence for the development of TQ as a novel treatment for metastatic bladder cancer.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Benzoquinonas/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Proteínas Wnt/metabolismo , beta Catenina/metabolismo , Benzoquinonas/química , Linhagem Celular Tumoral , Ensaios de Migração Celular , Movimento Celular/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Estrutura Molecular , Proteínas Wnt/genética , beta Catenina/genética
2.
Biochemistry (Mosc) ; 85(2): 167-176, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32093593

RESUMO

Thymoquinone is one of the main active components of the essential oil from black cumin (Nigella sativa) seeds. Thymoquinone exhibits a wide range of pharmacological activities, including neuroprotective action demonstrated in the models of brain ischemia/reperfusion, Alzheimer's and Parkinson's diseases, and traumatic brain injury. The neuroprotective effect of thymoquinone is mediated via inhibition of lipid peroxidation, downregulation of proinflammatory cytokines, maintenance of mitochondrial membrane potential, and prevention of apoptosis through inhibition of caspases-3, -8, and -9. Thymoquinone-based mitochondria-targeted antioxidants are accumulated in the mitochondria and exhibit neuroprotective properties in nanomolar concentrations. Thymoquinone reduces the negative effects of acute and chronic forms of brain pathologies. The mechanisms of the pharmacological action of thymoquinone and its chemical derivatives require more comprehensive studying. In this paper, we formulated the prospects of application of thymoquinone and thymoquinone-based drugs in the therapy of neurodegenerative diseases.


Assuntos
Benzoquinonas/farmacologia , Doenças Neurodegenerativas/tratamento farmacológico , Fármacos Neuroprotetores/farmacologia , Doença Aguda , Benzoquinonas/química , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/patologia , Doença Crônica , Humanos , Doenças Neurodegenerativas/metabolismo , Doenças Neurodegenerativas/patologia , Fármacos Neuroprotetores/química
3.
Life Sci ; 244: 117299, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31953157

RESUMO

AIMS: Notch signaling is highly implicated in several cancers and chemoresistance. Therefore, Notch-targeted therapies might be beneficial in enhancing chemotherapeutic effect and cancer regression. This study aimed to investigate implication of Notch in development and progression of solid Ehrlich carcinoma (SEC) and enhancement of anticancer effect of cisplatin (CIS) by addition of thymoquinone (TQ) and pentoxifylline (PTX) through modulation of Notch. MAIN METHODS: SEC was induced in mice as model for mammary carcinoma by s.c. injection of 1 × 106 Ehrlich cells into back of the mice. On 12th day, solid tumor was developed and mice were divided into seven groups; tumor control, early CIS (ECIS), ECIS + ETQ, ECIS + ETQ + EPTX, late CIS (LCIS), LCIS + LTQ, and LCIS + LTQ + LPTX. Early treatment was started on 12th day, whereas late treatment was begun on 19th day from tumor inoculation. At the endpoint, samples were collected for detection of Notch1, Hes1, Jagged1, ß-catenin, TNF-α, IL-6, IFN-γ, IL-2, VEGF, apoptosis, CD4, and CD8. KEY FINDINGS: Adding PTX and TQ to CIS significantly reduced Notch1, Hes1, Jagged1, ß-catenin, TNF-α, IL-6, IFN-γ, and VEGF with increment in IL-2, CD4, CD8, and apoptotic cells. Moreover, early treated groups showed remarkable attenuation in tumor growth and the relevant parameters compared to their counterpart later groups. SIGNIFICANCE: Addition of PTX with TQ to CIS showed a synergistic chemotherapeutic action and induced better oncostatic effect mainly through Notch suppression. Consequently, shutting Notch could be of great interest in promoting chemosensetivity and cancer control.


Assuntos
Benzoquinonas/farmacologia , Pentoxifilina/farmacologia , Receptores Notch/metabolismo , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/metabolismo , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Apoptose/efeitos dos fármacos , Benzoquinonas/metabolismo , Carcinoma de Ehrlich/tratamento farmacológico , Carcinoma de Ehrlich/metabolismo , Cisplatino/metabolismo , Cisplatino/farmacologia , Feminino , Camundongos , Pentoxifilina/metabolismo , Receptor Notch1/metabolismo , Transdução de Sinais/efeitos dos fármacos
4.
Chem Biol Interact ; 317: 108945, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31935363

RESUMO

Liver fibrosis is a common pathological consequence of liver injury, which increases liver failure-related morbidity and mortality. Hence, anti-fibrotic treatment is urgently needed. Oxidative stress plays a pivotal role in the progression of liver fibrosis. Thus, targeting ROS may be an effective strategy for liver fibrosis treatment. In this study, we investigated four benzoquinones derivatives, including 5-isopropyl-2-methyl-1,4-benzoquinone (TQ), 2-tert-butyl-1,4-benzoquinone (tBu-Q) 2,5-dimethyl-p-benzoquinone (Dime-Q) and p-benzoquinone (Ph-Q), as well as the evaluation of their antioxidant activity and anti-fibrotic effects on activated hepatic stellate cells and TAA-induced mice. Electrochemical analysis showed that all compounds possessed antioxidant property. The result was first confirmed by in vitro experiments, which revealed potential anti-fibrotic activity of all four compounds at the cellular level. Benzoquinone derivatives act as ROS-scavenging molecules, which modulated the TLR4-CD14 signaling pathway to inhibit the expression of procaspase-1 and IL-1ß in cells, induced apoptosis via a mitochondrial pathway by upregulating the ratio of Bax/Bcl-2 and by activating caspase-3, as well as inhibited the expression of the anti-apoptotic proteins FLIP and XIAP in activated LX-2 cells. In addition, a TAA (Thioacetamide)-induced mouse model was used to further validate the results. Treatment with benzoquinone derivatives significantly decreased the levels of liver injury markers and lipid peroxidation caused by excessive ROS, including aspartate aminotransferase (AST), alanine aminotransferase (ALT), and malondialdehyde (MDA). Moreover, treatment with benzoquinone derivatives significantly inhibited extracellular matrix (ECM) deposition and downregulated the mRNA and protein expression of liver fibrosis markers, such as collagen I, alpha-smooth muscle actin (α-SMA), and TIMP-1. In summary, these results indicate that benzoquinone derivatives may act as potential therapeutic drugs against liver fibrosis.


Assuntos
Antioxidantes/farmacologia , Benzoquinonas/farmacologia , Células Estreladas do Fígado/efeitos dos fármacos , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/tratamento farmacológico , Tioacetamida/toxicidade , Actinas/genética , Actinas/metabolismo , Animais , Biomarcadores , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Colágeno Tipo I/genética , Colágeno Tipo I/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Inflamação/metabolismo , Inflamação/prevenção & controle , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Estresse Oxidativo , Inibidor Tecidual de Metaloproteinase-1/genética , Inibidor Tecidual de Metaloproteinase-1/metabolismo
5.
J Enzyme Inhib Med Chem ; 35(1): 565-573, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31969031

RESUMO

Embelin is a naturally occurring para-benzoquinone isolated from Embelia ribes (Burm. f.) of the Myrsinaceae family. It was first discovered to have potent inhibitory activity (IC50 = 4.2 µM) against α-glucosidase in this study. Then, four series of novel embelin derivatives were designed, prepared and evaluated in α-glucosidase inhibition assays. The results show that most of the embelin derivatives synthesised are effective α-glucosidase inhibitors, with IC50 values at the micromolar level, especially 10d, 12d, and 15d, the IC50 values of which are 1.8, 3.3, and 3.6 µM, respectively. Structure-activity relationship (SAR) studies suggest that hydroxyl groups in the 2/5-position of para-benzoquinone are very important, and long-chain substituents in the 3-position are highly preferred. Moreover, the inhibition mechanism and kinetics studies reveal that all of 10d, 12d, 15d, and embelin are reversible and mixed-type inhibitors. Furthermore, docking experiments were carried out to study the interactions between 10d and 15d with α-glucosidase.


Assuntos
Benzoquinonas/farmacologia , Desenho de Drogas , Inibidores de Glicosídeo Hidrolases/farmacologia , alfa-Glucosidases/metabolismo , Benzoquinonas/síntese química , Benzoquinonas/química , Relação Dose-Resposta a Droga , Embelia/química , Inibidores de Glicosídeo Hidrolases/síntese química , Inibidores de Glicosídeo Hidrolases/química , Humanos , Simulação de Acoplamento Molecular , Estrutura Molecular , Relação Estrutura-Atividade
6.
Planta Med ; 86(1): 45-54, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31663108

RESUMO

A previous study showed that the meroterpenoid-rich fraction of an ethanolic extract of Sargassum serratifolium (MES) stimulated adipose tissue browning and inhibited diet-induced obesity and metabolic syndrome. Sargaquinoic acid (SQA) is a major component in MES. We investigated the effects of SQA on the differentiation of preadipocytes to the beige adipocytes. SQA was treated in 3T3-L1 adipocytes differentiated under a special condition that has been reported to induce the browning of adipocytes. SQA at 10 µM reduced lipid accumulation by approximately 23%. SQA at 2.5 - 10 µM induced the differentiation of white adipocytes to beige adipocytes partially by increasing the mitochondrial density and the expression of beige/brown adipocyte markers. In addition, SQA activated lipid catabolic pathways, evidenced by the increased expression levels of perilipin, carnitine palmitoyltransferase 1, and acyl-CoA synthetase long-chain family member 1. As a partial mechanism, biochemical and in silico analyses indicate that SQA activated AMP-activated protein kinase signaling in adipocytes.


Assuntos
Adipócitos Marrons/efeitos dos fármacos , Adipogenia/efeitos dos fármacos , Alcenos/farmacologia , Benzoquinonas/farmacologia , Sargassum/química , Células 3T3-L1 , Proteínas Quinases Ativadas por AMP/metabolismo , Adipócitos Marrons/citologia , Alcenos/isolamento & purificação , Alcenos/toxicidade , Animais , Benzoquinonas/isolamento & purificação , Benzoquinonas/toxicidade , Camundongos , Transdução de Sinais/efeitos dos fármacos
7.
Exp Parasitol ; 209: 107810, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31801691

RESUMO

Fasciolosis is a neglected tropical disease caused by the liver fluke Fasciola gigantica. The absence of successful vaccine and emerging resistance in flukes against the drug of choice, triclabendazole, has necessitated the search for alternatives including phyto-therapeutic approaches. Curcumin and thymoquinone, the active ingredients of Curcuma longa and Nigella sativa plants respectively, were first screened for their binding affinity with Glutathione-S-transferase (GST) molecule through in silico molecular docking followed by in vitro treatment of worms with varying concentrations of the test compounds. The in silico molecular docking of curcumin and thymoquinone with sigma GST revealed strong hydrogen bonding as well as hydrophobic interactions with high fitness scores but showing inter-specific differences. The in vitro treatment of F. gigantica worms with both curcumin and thymoquinone resulted in a significant increase in the generation of reactive oxygen species (ROS) whereas the level of reduced glutathione, a primary redox regulator, was found to be significantly decreased (p < 0.05). The two compounds not only inhibited the GST activity, which is an important detoxification enzyme and also a key drug/vaccine target for the control of fasciolosis but also significantly inhibited the activity of antioxidant enzymes glutathione peroxidase and glutathione reductase that are vital in maintenance of redox homeostasis. The immunohistochemistry performed using anti sigma GST polyclonal antibodies revealed that both the compounds used in the present study significantly reduced immunofluorescence in the vitellaria, developing eggs present in the ovary and the intestinal caecae indicating inhibition of GST enzyme in these regions of the worms. Further, following treatment with curcumin and thymoquinone, chromatin condensation and DNA fragmentation was also observed in F. gigantica worms. In conclusion, both curcumin and thymoquinone generated oxidative stress in the worms by production of ROS and significantly inhibiting their antioxidant and detoxification ability. The oxidative stress along with induction of apoptotic like events would compromise the survival ability of worms within the host. However, further studies are required to establish their anthelmintic potential alone and in combination with the commonly used anthelmintic drugs under in vivo conditions.


Assuntos
Apoptose/efeitos dos fármacos , Benzoquinonas/farmacologia , Curcumina/farmacologia , Fasciola/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Animais , Benzoquinonas/química , Búfalos , Cromatina/efeitos dos fármacos , Curcumina/química , Dano ao DNA/efeitos dos fármacos , Fragmentação do DNA/efeitos dos fármacos , Eletroforese em Gel de Ágar , Inibidores Enzimáticos/farmacologia , Fasciola/citologia , Fasciola/metabolismo , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Glutationa Redutase/metabolismo , Glutationa Transferase/antagonistas & inibidores , Glutationa Transferase/química , Glutationa Transferase/metabolismo , Imuno-Histoquímica , Microscopia Confocal , Modelos Moleculares , Simulação de Acoplamento Molecular , Espécies Reativas de Oxigênio/metabolismo
8.
Toxicol Lett ; 320: 19-27, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31778773

RESUMO

The deleterious effects of glucocorticoids on glucose homeostasis limit their clinical use. There is substantial evidence demonstrating that islet function impaired by long-term glucocorticoids exposure is a core defect in the progression of impaired glucose tolerance to diabetes. The activity of heat-shock protein (Hsp) 90 is required to maintain the hormone-binding activity and stability of glucocorticoid receptor (GR). In the present study, Hsp90 inhibition by 17-DMAG counteracted dexamethasone-mediated inhibition of glucose-stimulated insulin secretion in isolated rat islets as well as expressions of neuropeptide Y (NPY) and somatostatin receptor 3 (SSTR3), two negative regulators of insulin secretion. Like 17-DMAG, both the pan-histone deacetylase (HDAC) inhibitor TSA and HDAC6 inhibitor Tubacin exhibited a similar action in protecting islet function against dexamethasone-induced injury, along with the downregulation of NPY and SSTR3 expressions. The hyperacetylation of Hsp90 by TSA and Tubacin disrupted its binding ability to GR and blocked dexamethasone-elicited nuclear translocation of GR in INS-1 ß-cell lines. In addition, Tubacin treatment triggered the GR protein degradation through the ubiquitin-proteasome pathway. These findings suggest that Hsp90 acetylation by inhibiting HDAC6 activity may be a potential strategy to prevent the development of steroid diabetes mellitus via alleviating glucocorticoid-impaired islet function.


Assuntos
Anilidas/farmacologia , Benzoquinonas/farmacologia , Dexametasona/toxicidade , Glucocorticoides/toxicidade , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Desacetilase 6 de Histona/antagonistas & inibidores , Inibidores de Histona Desacetilases/farmacologia , Ácidos Hidroxâmicos/farmacologia , Insulina/metabolismo , Ilhotas Pancreáticas/efeitos dos fármacos , Lactamas Macrocíclicas/farmacologia , Acetilação , Animais , Linhagem Celular , Proteínas de Choque Térmico HSP90/metabolismo , Desacetilase 6 de Histona/metabolismo , Ilhotas Pancreáticas/metabolismo , Masculino , Complexo de Endopeptidases do Proteassoma/metabolismo , Processamento de Proteína Pós-Traducional , Proteólise , Ratos Sprague-Dawley , Via Secretória , Técnicas de Cultura de Tecidos
9.
Chem Biodivers ; 16(12): e1900503, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31660678

RESUMO

A series of 2,5-bis(alkyl/arylamino)-1,4-benzoquinones (1-12) were investigated in vitro for their potential to inhibit the activity of jack bean urease. Compounds 1-6, 8, 9, 11 and 12 effectively inhibited the jack bean urease activity by 90.8 % when tested at 5 µm, whereas 7 and 10 had relatively little effect. The IC50 for most compounds was in the nanomolar range (31.4 nm and 36.0 nm for 2 and 8, respectively). The mechanism of enzyme inhibition shown by 2 and 8 is typical of mixed-type inhibitors, whose affinity for the active site is over 6- and 2-fold higher (Ki =30.0 and 22.8 nm, for 2 and 8, respectively) than that of an allosteric site. Molecular docking studies revealed that both 2 and 8 establish hydrogen bonds with the amino acids residues Asp494, Met588, His593 and Ala636 in the active site of jack bean urease. These results indicate that such aminoquinones are useful leads for the development of more efficient urease inhibitors of wider utility.


Assuntos
Benzoquinonas/química , Inibidores Enzimáticos/química , Urease/antagonistas & inibidores , Sítio Alostérico , Benzoquinonas/metabolismo , Benzoquinonas/farmacologia , Canavalia/enzimologia , Domínio Catalítico , Inibidores Enzimáticos/metabolismo , Inibidores Enzimáticos/farmacologia , Cinética , Simulação de Acoplamento Molecular , Relação Estrutura-Atividade , Urease/metabolismo
10.
Neurochem Res ; 44(11): 2643-2657, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31606837

RESUMO

Schwann cells (SCs) play an important role in producing myelin for rapid neurotransmission in the peripheral nervous system. Activation of the differentiation and myelination processes in SCs requires the expression of a series of transcriptional factors including Sox10, Oct6/Pou3f1, and Egr2/Krox20. However, functional interactions among several transcription factors are poorly defined and the important components of the regulatory network are still unknown. Until now, available evidence suggests that SCs require cAMP signaling to initiate the myelination program. Heat shock protein 90 (Hsp90) is known as a chaperone required to stabilize ErbB2 receptor. In recent years, it was reported that cAMP transactivated the ErbB2/ErbB3 signaling in SCs. However, the relationship between Hsp90 and cAMP-induced differentiation in SCs is undefined. Here we investigated the role of Hsp90 during cAMP-induced differentiation of SCs using Hsp90 inhibitor, geldanamycin and Hsp90 siRNA transfection. Our results showed that dibutyryl-cAMP (db-cAMP) treatment upregulated Hsp90 expression and led to nuclear translocation of Gab1/ERK, the downstream signaling pathway of the ErbB2 signaling mechanism in myelination. The expression of myelin-related genes and nuclear translocation of Gab1/ERK following db-cAMP treatment was inhibited by geldanamycin pretreatment and Hsp90 knockdown. These findings suggest that Hsp90 might play a role in cAMP-induced differentiation via stabilization of ErbB2 and nuclear translocation of Gab1/ERK in SCs.


Assuntos
Diferenciação Celular/fisiologia , Proteínas de Choque Térmico HSP90/fisiologia , Células de Schwann/fisiologia , Animais , Benzoquinonas/farmacologia , Bucladesina/farmacologia , MAP Quinases Reguladas por Sinal Extracelular/genética , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Expressão Gênica , Técnicas de Silenciamento de Genes , Proteínas de Choque Térmico HSP90/genética , Lactamas Macrocíclicas/farmacologia , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Ratos Sprague-Dawley , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Células de Schwann/citologia , Regulação para Cima
11.
Exp Eye Res ; 189: 107821, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31589841

RESUMO

Posterior capsule opacification (PCO) is a common complication of cataract surgery, resulting from a combination of proliferation, migration, epithelial-mesenchymal transition (EMT) of residual capsular epithelial cells and fibrosis of myofibroblasts. HSP90 is known to regulate the proteostasis of cells under pathophysiological conditions. The role of HSP90 in PCO formation, however, is not clear. To do this, the lens epithelial cell lines and an ex vivo cultured rat capsular bag model were used to study the role of HSP90 in PCO formation. The expression of protein and mRNA was measured by immunoblotting and quantitative RT-PCR, and cell apoptosis was measured by TUNEL(TdT-mediated dUTP nick-end labeling). The cell proliferation was measured by cell viability assays. The results showed that 17-AAG (Tanespimycin), an inhibitor of HSP90, suppresses the proliferation of immortalized lens epithelial cell lines HLE-B3, SRA01/04, and mLEC, with IC50 values of 0.27, 0.27, and 0.49 µM, respectively. In an ex vivo cultured rat capsular model, the capsular residual epithelial cells resisted the stress of the capsulorhexis surgery and took 3-6 days to completely overlay the capsular posterior wall. During this process, heat shock factor 1 and its downstream targets HSP90, HSP25, αB-crystallin, and HSP40 were upregulated. Treatment with 17-AAG inhibited the viability of capsular residual epithelial cells and induced the cells apoptosis, characterized by increases in ROS levels, apoptotic DNA injury, and the activation of caspases 9 and 3. HSP90 participated in regulating both EGF receptor (EGFR) and TGF receptor (TGFR) signaling pathways. HSP90 was found to interact with the EGFR, such that inhibition of HSP90 by 17-AAG destabilized the EGFR protein and suppressed p-ERK1/2 and p-AKT levels. 17-AAG also inhibited the TGF-ß-induced phosphorylation of SMAD2/3 and ERK1/2 and the decrease in E-cadherin and ZO-1 expression. Accordingly, these data suggest that the induction of HSP90 protects capsular residual epithelial cells against capsulorhexis-induced stress and participates in regulating the processes of proliferation, EMT and migration of rat capsular residual epithelial cells, at least partly, through the EGFR and TGFR signaling pathways. Treatment with 17-AAG suppresses PCO formation and is therefore a potential therapeutic candidate for PCO prevention.


Assuntos
Benzoquinonas/farmacologia , Opacificação da Cápsula/tratamento farmacológico , Células Epiteliais/metabolismo , Proteínas de Choque Térmico HSP90/efeitos dos fármacos , Lactamas Macrocíclicas/farmacologia , Cápsula Posterior do Cristalino/metabolismo , Animais , Western Blotting , Opacificação da Cápsula/metabolismo , Opacificação da Cápsula/patologia , Movimento Celular , Proliferação de Células , Células Cultivadas , Modelos Animais de Doenças , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/patologia , Proteínas de Choque Térmico HSP90/metabolismo , Cápsula Posterior do Cristalino/patologia , Ratos , Ratos Wistar , Transdução de Sinais
12.
Mater Sci Eng C Mater Biol Appl ; 104: 109881, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31499940

RESUMO

Thymoquinone (TQ) loaded monodispersed mesoporous silica nanoparticles (TQ-MSNPs) with size of 188 ±â€¯3 nm were prepared and characterized using DLS, TEM and FTIR. These TQ-MSNPs overcome the limitations of free TQ like hydrophobicity, low aqueous and photo stability and thus enhance its anticancer activity. In vitro release kinetics showed biphasic drug release where up to 50% was released in first 8 h and subsequently 98% released after 48 h. Enhanced cytotoxicity of TQ-MSNPs was observed against MCF-7 and HeLa cell lines as compared to free TQ. DAPI and Annexin V-FITC/PI staining confirmed the induction of apoptosis in cancer cells following treatment with TQ-MSNPs. Also, TQ-MSNPs exhibited enhanced anti-invasion properties against both cell lines as very low concentration of loaded TQ imparts similar benefits as free TQ. Both TQ and TQ-MSNPs exerted their cytotoxicity via reactive oxygen species (ROS) generation, as addition of an antioxidant NAC attenuated their killing activity.


Assuntos
Apoptose/efeitos dos fármacos , Benzoquinonas/farmacologia , Nanopartículas/química , Invasividade Neoplásica/patologia , Dióxido de Silício/química , Antioxidantes/química , Antioxidantes/farmacologia , Benzoquinonas/química , Linhagem Celular Tumoral , Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos , Células HeLa , Humanos , Células MCF-7 , Porosidade , Espécies Reativas de Oxigênio/metabolismo
13.
Mol Cell Biochem ; 462(1-2): 195-206, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31493190

RESUMO

Thymoquinone (TQ) is a highly perspective chemotherapeutic agent against gliomas and glioblastomas because of its ability to cross the blood-brain barrier and its selective cytotoxicity for glioblastoma cells compared to primary astrocytes. Here, we tested the hypothesis that TQ-induced mild oxidative stress provokes C6 glioma cell apoptosis through redox-dependent alteration of MAPK proteins. We showed that low concentrations of TQ (20-50 µM) promoted cell-cycle arrest and induced hydrogen peroxide generation as a result of NADH-quinone oxidoreductase 1-catalyzed two-electron reduction of this quinone. Similarly, low concentrations of TQ efficiently conjugated intracellular GSH disturbing redox state of glioma cells and provoking mitochondrial dysfunction. We demonstrated that high concentrations of TQ (70-100 µM) induced reactive oxygen species generation due to its one-electron reduction. TQ provoked apoptosis in C6 glioma cells through mitochondrial potential dissipation and permeability transition pore opening. The identified TQ modes of action on C6 glioma cells open up the possibility of considering it as a promising agent to enhance the sensitivity of cancer cells to standard chemotherapeutic drugs.


Assuntos
Apoptose/efeitos dos fármacos , Benzoquinonas/farmacologia , Glioma/patologia , Estresse Oxidativo/efeitos dos fármacos , Animais , Benzoquinonas/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Glioma/enzimologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Oxirredução , Fosfatidilinositol 3-Quinases/metabolismo , Ratos
14.
Biomed Pharmacother ; 118: 109360, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31545222

RESUMO

BACKGROUND/AIMS: Embelin is an active component isolated from Embelia ribes Burm. In this study, we explored the protective effects of embelin on acute liver injury. METHODS: An animal model of acute liver injury was established via administration of a single injection of thioacetamide (TAA) (300 µg/g body weight) to adult mice. Embelin was administered by intragastric gavage at 50 µg/g body weight starting 2 days before TAA administration and continuing throughout the study. Survival of the mice was analyzed by the Kaplan-Meier method using the log-rank test. The acute liver injury protocol was repeated and the remaining mice were analyzed at indicated times. Hematoxylin and eosin staining and picrosirius red staining were used to examine necrosis/inflammation and liver healing, respectively. Liver function was assessed by serum alanine aminotransferase/alkaline phosphatase activity. Hepatic cleaved caspase-3 and F4/80 expression levels were examined via immunostaining. Statistical analysis was performed with GraphPad Software. RESULTS: The survival and liver function of the mice were markedly better in the group treated with embelin prior to TAA toxication than in the TAA toxication-only group. Embelin significantly reduced TAA-induced hepatic necrosis/apoptosis. Massive inflammatory cell infiltration, which is consistent with hepatic fibrogenesis (a healing process), occurred earlier in the embelin-treated recovery group than in the spontaneous recovery group. Moreover, macrophage activities increased more rapidly with embelin treatment. CONCLUSIONS: In summary, embelin can protect against acute liver injury. Its therapeutic value warrants further exploration.


Assuntos
Benzoquinonas/farmacologia , Fígado/lesões , Substâncias Protetoras/farmacologia , Doença Aguda , Animais , Apoptose/efeitos dos fármacos , Feminino , Inflamação/patologia , Fígado/efeitos dos fármacos , Fígado/patologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Macrófagos/patologia , Camundongos Endogâmicos C57BL , Necrose , Análise de Sobrevida , Tioacetamida , Cicatrização/efeitos dos fármacos
15.
Int J Nanomedicine ; 14: 5503-5526, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31410001

RESUMO

Background and purpose: Glioma is one of the most aggressive primary brain tumors and is incurable. Surgical resection, radiation, and chemotherapies have been the standard treatments for brain tumors, however, they damage healthy tissue. Therefore, there is a need for safe anticancer drug delivery systems. This is particularly true for natural prodrugs such as thymoquinone (TQ), which has a high therapeutic potential for cancers but has poor water solubility and insufficient targeting capacity. We have tailored novel core-shell nanoformulations for TQ delivery against glioma cells using mesoporous silica nanoparticles (MSNs) as a carrier. Methods: The core-shell nanoformulations were prepared with a core of MSNs loaded with TQ (MSNTQ), and the shell consisted of whey protein and gum Arabic (MSNTQ-WA), or chitosan and stearic acid (MSNTQ-CS). Nanoformulations were characterized, studied for release kinetics and evaluated for anticancer activity on brain cancer cells (SW1088 and A172) and cortical neuronal cells-2 (HCN2) as normal cells. Furthermore, they were evaluated for caspase-3, cytochrome c, cell cycle arrest, and apoptosis to understand the possible anticancer mechanism. Results: TQ release was pH-dependent and different for core and core-shell nanoformulations. A high TQ release from MSNTQ was detected at neutral pH 7.4, while a high TQ release from MSNTQ-WA and MSNTQ-CS was obtained at acidic pH 5.5 and 6.8, respectively; thus, TQ release in acidic tumor environment was enhanced. The release kinetics fitted with the Korsmeyer-Peppas kinetic model corresponding to diffusion-controlled release. Comparative in vitro tests with cancer and normal cells indicated a high anticancer efficiency for MSNTQ-WA compared to free TQ, and low cytotoxicity in the case of normal cells. The core-shell nanoformulations significantly improved caspase-3 activation, cytochrome c triggers, cell cycle arrest at G2/M, and apoptosis induction compared to TQ. Conclusion: Use of MSNs loaded with TQ permit improved cancer targeting and opens the door to translating TQ into clinical application. Particularly good results were obtained for MSNTQ-WA.


Assuntos
Antineoplásicos/uso terapêutico , Benzoquinonas/uso terapêutico , Composição de Medicamentos , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Glioma/tratamento farmacológico , Nanopartículas/química , Dióxido de Silício/química , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Benzoquinonas/farmacologia , Materiais Biocompatíveis/química , Encéfalo/patologia , Varredura Diferencial de Calorimetria , Caspase 3/metabolismo , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Quitosana/química , Citocromos c/metabolismo , Difusão , Ativação Enzimática/efeitos dos fármacos , Humanos , Concentração de Íons de Hidrogênio , Concentração Inibidora 50 , Cinética , Nanopartículas/ultraestrutura , Porosidade , Espectroscopia de Infravermelho com Transformada de Fourier , Termogravimetria
16.
Biomed Res ; 40(4): 169-178, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31413238

RESUMO

Migration of osteoblasts to the sites resorbed by osteoclasts is an essential step in bone remodeling. However, the exact mechanism of osteoblast migration is still not known. We have shown that platelet-derived growth factor (PDGF)-BB induces the migration of osteoblast-like MC3T3-E1 cells through the activation of p38 mitogen-activated protein (MAP) kinase, c-Jun N-terminal kinase (JNK) and p44/p42 MAP kinase. Evidence is accumulating that heat shock protein 90 (HSP90) acts as a central regulator of proteostasis under stress conditions and physiological cell functions. In the present study, using transwell cell migration assay and wound-healing assay, we investigated the involvement of HSP90 in the PDGF-BB-stimulated migration of MC3T3-E1 cells, and the underlying signaling mechanism estimated by Western blot analyses. Onalespib, an HSP90 inhibitor, significantly reduced the PDGF-BB-stimulated migration evaluated by the two types of migration assays. The cell migration was also suppressed by geldanamycin, another type of HSP90 inhibitor. Onalespib markedly attenuated the PDGF-BB-elicited phosphorylation of p44/p42 MAP kinase without affecting that of p38 MAP kinase or JNK. In addition, the phosphorylation of p44/p42 MAP kinase by PDGF-BB was reduced by geldanamycin. Taken together, these results strongly suggest that HSP90 inhibitors suppress the PDGF-BB-induced osteoblast migration through the attenuation of p44/p42 MAP kinase activity.


Assuntos
Becaplermina/farmacologia , Benzamidas/farmacologia , Benzoquinonas/farmacologia , Movimento Celular/efeitos dos fármacos , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Isoindóis/farmacologia , Lactamas Macrocíclicas/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Osteoblastos/metabolismo , Animais , Linhagem Celular , Proteínas de Choque Térmico HSP90/metabolismo , Camundongos , Fosforilação/efeitos dos fármacos
17.
Chem Biol Interact ; 312: 108799, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31433961

RESUMO

Black seed (Nigella sativa) oil has been used in various dermatological applications, and its major constituent, thymoquinone (TQ) has been shown to exhibit antiproliferative activity against various cancer cells. In this study, we tried to provide a mechanistic basis of apoptosis induced by TQ. Skin squamous carcinoma A431 cells were treated with TQ to monitor the apoptosis induced by TQ. Western blot analysis was performed to detect expression of apoptotic or anti-apoptotic proteins. Cell viability and apoptosis were measured by using the MTT test and FACS analysis, respectively. The induction of intracellular reactive oxygen species (ROS) by TQ was evaluated by 2',7'-dichlorofluorescein diacetate staining. In vivo xenograft study was followed to confirm the antiproliferative effect of TQ. Treatment of A431 cells with TQ-induced apoptosis, which was associated with the induction of p53 and Bax, inhibition of Mdm2, Bcl-2, and Bcl-xl expression, and activation of caspase-9, -7, and -3. TQ inhibited the constitutive phosphorylation and DNA binding activity of signal transducer and activator of transcription-3 (STAT3) in A431 cells by blocking the phosphorylation of the upstream kinase, Src. Moreover, the expression of STAT3 target gene products, cyclin D1 and survivin, was attenuated by TQ treatment. The generation of ROS was increased during TQ-induced apoptosis, and the pretreatment of N-acetyl cysteine, a ROS scavenger, reversed the apoptotic effect of TQ. In vivo study with NOD scid gamma (NSG) mice confirmed the inhibitory effect of TQ on the growth of A431 cells. Our results provide the first demonstration that TQ induces the apoptosis of A431 cells through generation of ROS and inhibition of STAT3 signaling.


Assuntos
Antineoplásicos/farmacocinética , Apoptose/efeitos dos fármacos , Benzoquinonas/farmacologia , Regulação para Baixo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Fator de Transcrição STAT3/metabolismo , Animais , Antineoplásicos/uso terapêutico , Benzoquinonas/uso terapêutico , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Humanos , Camundongos , Camundongos Endogâmicos NOD , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Transplante Heterólogo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
18.
J Pharmacol Sci ; 140(3): 255-262, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31402210

RESUMO

Heat shock protein 90 (HSP90) antagonists are currently being evaluated as potential anticancer drugs. However, adverse effects related to these drugs, such as fatigue and pain, suggest that they affect neurons. Therefore, to understand the influence of HSP90 inhibitors on neurons, we investigated the effects of geldanamycin, an HSP90 antagonist, on nerve growth factor (NGF)-differentiated pheochromocytoma 12 (PC12) cells, particularly, on the expression and phosphorylation of proteins and kinases in the NGF pathway. Geldanamycin significantly inhibited NGF-induced neurite outgrowth and phosphorylation of Akt and extracellular signal-related kinase 1/2 in PC12 cells. Furthermore, geldanamycin inhibited the phosphorylation of collapsin response mediator protein 2 and the expression of cyclin-dependent kinase 5 in the presence of NGF, but did not significantly affect the expression of glycogen synthase kinase 3ß. These results suggest that geldanamycin influences microtubule-binding proteins and kinases relating to neurite outgrowth, thereby inducing neuronal impairment.


Assuntos
Neoplasias das Glândulas Suprarrenais/tratamento farmacológico , Benzoquinonas/farmacologia , Diferenciação Celular/efeitos dos fármacos , Lactamas Macrocíclicas/farmacologia , Fator de Crescimento Neural/metabolismo , Neuritos/efeitos dos fármacos , Crescimento Neuronal/efeitos dos fármacos , Feocromocitoma/tratamento farmacológico , Neoplasias das Glândulas Suprarrenais/metabolismo , Animais , Linhagem Celular Tumoral , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Glicogênio Sintase Quinase 3 beta/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Neuritos/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Células PC12 , Feocromocitoma/metabolismo , Fosforilação/efeitos dos fármacos , Ratos , Transdução de Sinais/efeitos dos fármacos
19.
Fitoterapia ; 138: 104297, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31404617

RESUMO

As a part of an ongoing bioprospective project, searching for potential medicinal plants from the Brazilian Atlantic Forest, Miconia willdenowii was selected for its potential leishmanicidal and antimicrobial activities. The crude ethanolic extract of M. willdenowii showed an inhibition of 99.7% of the promastigote forms of Leishmania amazonensis at the concentration of 80 µg/mL. Further investigation of its antimicrobial activity against pathogenic fungi and Gram positive and negative bacteria, revealed a significant antimicrobial activity. A bioguided study with its liquid-liquid partition fractions revealed the hexane fraction (Hex) as the most active against Leishmania, inhibiting 99.2% and 46.9% of the protozoan at concentrations of 40 and 20 µg/mL, respectively. Hex also showed significant antimicrobial activity against Staphylococcus aureus and Candida krusei with IC50 of 15.6 and 62.5 µg/mL, respectively. Purification of Hex led to the isolation of 2-methoxy-6-pentyl-benzoquinone (1, also known as primin) as the active metabolite, probably responsible for the observed antimicrobial and anti-leishmania effects. Primin (1) disclosed leishmanicidal activity (IC50 = 1.25 µM), showing higher potency than the standard drug amphotericin B (IC50 = 5.08 µM), with additional antifungal effects against all tested fungi species. Compound 1 also showed significant activity against S. aureus (IC50 = 8.94 µM), showing a comparable potency with the reference drug chloramphenicol (IC50 = 6.19 µM), but with a potential cytotoxicity towards peripheral human blood mononuclear cells (CC50 = 255.15 µM). Here in, the antimicrobial and anti-L. amazonensis effects of M. willdenowii are reported for the first time, as well as Primin (1) as its probable bioactive metabolite.


Assuntos
Antibacterianos/farmacologia , Antiprotozoários/farmacologia , Benzoquinonas/farmacologia , Melastomataceae/química , Extratos Vegetais/farmacologia , Antibacterianos/isolamento & purificação , Antiprotozoários/isolamento & purificação , Benzoquinonas/isolamento & purificação , Brasil , Humanos , Leishmania/efeitos dos fármacos , Leucócitos Mononucleares/efeitos dos fármacos , Folhas de Planta/química , Plantas Medicinais/química , Staphylococcus aureus/efeitos dos fármacos
20.
J Therm Biol ; 84: 1-7, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31466741

RESUMO

Heat can trigger testicular damage and impair fertility. Leydig cells produce testosterone in response to stimulation by luteinizing hormone (LH), which induces Ca2+ entry and K+ efflux through ion channels in their plasma membrane. Considering that mechanisms coordinating the Leydig cell responses to hyperthermic stress remain unclear; the present study analyzed the effects of heat stress (HS, 43°C, 15 min) and inhibition of Hsp90 on T-type calcium currents and voltage-dependent potassium currents (VKC) in mice Leydig cells. Results show that HS reduced the VKC steady state currents at +80 mV (45.3%) and maximum conductance (71.5%), as well as increased the activation time constant (31.7%) and the voltage for which half the channels are open (30%). Hsp90 inhibition did not change the VKC currents. T-type calcium currents were not affected by HS or Hsp90 inhibition. In conclusion, HS can slow the activation, reduce the currents and voltage dependence of the VKC, suggesting a possible role of these currents in the response to hyperthermic stress in Leydig cells.


Assuntos
Canais de Cálcio Tipo T/fisiologia , Proteínas de Choque Térmico HSP90/fisiologia , Resposta ao Choque Térmico/fisiologia , Células Intersticiais do Testículo/fisiologia , Canais de Potássio de Abertura Dependente da Tensão da Membrana/fisiologia , Animais , Benzoquinonas/farmacologia , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Temperatura Alta , Lactamas Macrocíclicas/farmacologia , Células Intersticiais do Testículo/efeitos dos fármacos , Masculino , Camundongos
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