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1.
Anticancer Res ; 39(10): 5461-5471, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31570440

RESUMO

BACKGROUND/AIM: Multidrug resistance (MDR) is often associated with overexpression of P-glycoprotein (ABCB1) in cancer cells. Apatinib is a novel Vascular endothelial growth factor receptor-TKI (VEGFR-TKI) which inhibits the function of ABCB1 in certain cancers. This study aimed to investigate the effect of apatinib on the reversal of paclitaxel (PTX) resistance in A549 lung cancer cells (A549/PTX) and related mechanisms. MATERIALS AND METHODS: A549/PTX cells were treated with apatinib alone, PTX alone, or PTX and apatinib. Cell viability was measured by the CCK8 assay. Apoptosis rate, cell-cycle arrest, Rhodamine efflux and reactive oxygen species (ROS) generation were determined by flow cytometry. The intracellular paclitaxel concentration was measured by ultra performance liquid chromatography (UPLC). Protein levels were analyzed by western blotting. RESULTS: A549/PTX cells had significant resistance to PTX and higher expression of ABCB1 compared to A549 cells. Apatinib increased the cytotoxicity of PTX, enhanced PTX-induced apoptosis and cycle arrest, and triggered intracellular ROS generation in A549/PTX cells. In addition, apatinib treatment increased the concentration of intracellular PTX in A549/PTX cells. Apatinib-PTX combination inhibited AKT and ERK pathways. CONCLUSION: Apatinib reverses the drug resistance to PTX in A549 PTX-resistant cells through inhibiting the function of ABCB1 and resumes anti-cancer effects.


Assuntos
Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Neoplasias Pulmonares/tratamento farmacológico , Paclitaxel/farmacologia , Piridinas/farmacologia , Células A549 , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Neoplasias Pulmonares/metabolismo , Espécies Reativas de Oxigênio/metabolismo
2.
Anticancer Res ; 39(10): 5483-5494, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31570442

RESUMO

BACKGROUND/AIM: Canine mammary gland tumors (CMGTs) are the most common tumors in female dogs. Rivoceranib (also known as apatinib) is a novel anti-angiogenic tyrosine kinase inhibitor that selectively binds to vascular endothelial growth factor receptor-2 (VEGFR2). The aim of this study was to disclose the antitumor effects of rivoceranib on CMGT cell lines. MATERIALS AND METHODS: The direct effects of rivoceranib on CMGT cells in vitro were analyzed by cell proliferation and migration assays. Cell-cycle distribution and apoptotic ratio were analyzed by flow cytometry. Expression levels of phosphorylated VEGFR2 were evaluated by western blot analysis. RESULTS: Rivoceranib treatment significantly reduced the proliferation and migration of CMGT cells in a dose-dependent manner. Flow cytometry results revealed significant increases in G0/G1 phase arrest and apoptosis proportional to the drug concentration used. Rivoceranib reduced the level of phosphorylated VEGFR2. CONCLUSION: We confirm that rivoceranib exerts antitumor effects on CMGT cells by inhibiting biological functions.


Assuntos
Antineoplásicos/farmacologia , Neoplasias Mamárias Animais/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Piridinas/farmacologia , Animais , Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Cães , Feminino , Fase G1/efeitos dos fármacos , Neoplasias Mamárias Animais/metabolismo , Fosforilação/efeitos dos fármacos , Fase de Repouso do Ciclo Celular/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/metabolismo
3.
Pestic Biochem Physiol ; 159: 80-84, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31400787

RESUMO

The plastid acetyl coenzyme carboxylase (ACCase) Trp1999Leu mutation was identified in a Beckmannia syzigachne population resistant to fenoxaprop-p-ethyl. The pattern of cross-resistance for the Trp1999Leu mutation is still ambiguous. In this paper, mutant homozygote (1999Leu/Leu, RR) and wild type (1999Trp/Trp, SS) B. syzigachne plants with the same genetic background were purified from the JS-26 population using the dCAPS method. The activity of ACCase in RR and SS was determined. Then, the cross-resistance pattern to ACCase inhibiting herbicides of the Trp1999Leu mutation was determined using the whole-plant method. ACCase activity showed that the Trp1999Leu mutation decreased ACCase sensitivity to fenoxaprop-p-ethyl by 2.73-fold. A dose-response experiment indicated that the Trp1999Leu mutation conferred high resistance to quizalofop-p-ethyl (20.29-fold), metamifop (12.22-fold) and pinoxaden (18.60-fold), moderate resistance to fenoxaprop-p-ethyl (8.20-fold) and sethoxydim (6.38-fold), low resistance to cyhalofop-butyl (2.73-fold) and no resistance to clodinafop-propargyl (1.42 fold) and clethodim (1.59-fold). This is the first report of the role of Trp1999Leu in fenoxaprop-p-ethyl resistance and of the patterns of cross-resistance to ACCase-inhibiting herbicides in B. syzigachne.


Assuntos
Acetil-CoA Carboxilase/genética , Herbicidas/farmacologia , Poaceae/efeitos dos fármacos , Poaceae/genética , Anilidas/farmacologia , Benzoxazóis/farmacologia , Cicloexanonas/farmacologia , Resistência a Herbicidas/genética , Compostos Heterocíclicos com 2 Anéis/farmacologia , Mutação/genética , Propionatos/farmacologia , Piridinas/farmacologia , Quinoxalinas/farmacologia
4.
Pestic Biochem Physiol ; 158: 40-46, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31378359

RESUMO

Aphis gossypii Glover is an economically important pest of numerous crops throughout the world. Some field populations of A.gossypii in China have developed moderate level of resistance to sulfoxaflor, a newly released sulfoximine insecticide for management of sap-feeding pests. To evaluate the effect of sulfoxaflor resistance on the fitness cost of A. gossypii, the life history traits of sulfoxaflor-resistant strain (SulR) and an isogenic susceptible strain (SS) were compared using the age-stage, two-sex life table approach. The results showed that the resistant strain had a reduction in fitness (relative fitness = 0.917), along with significantly decreases in longevity, fecundity, net reproductive (R0), mean generation time (T) and gross reproductive rate (GRR). Compared to the susceptible strain, SulR strain showing a shorter developmental duration of each nymph instar stage. Moreover, the adult pre-oviposition period (APOP) and total preoviposition period (TPOP) of SulR strain were also significantly shorter than that of the susceptible strain. Investigation of six development and reproduction related genes indicated that EcR, USP and JHBP were overexpressed in the SulR strain, while the mRNA transcript level of Vg was decreased significantly compared to the susceptible strain. These results suggest that there is a fitness cost associated with sulfoxaflor resistance in A. gossypii and the different expression of EcR, USP, JHBP, and Vg may play very important role in this trade-off.


Assuntos
Afídeos/efeitos dos fármacos , Inseticidas/farmacologia , Piridinas/farmacologia , Compostos de Enxofre/farmacologia , Animais , Afídeos/genética , Afídeos/metabolismo , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Resistência a Inseticidas/genética , Ninfa/efeitos dos fármacos , Ninfa/genética , Ninfa/metabolismo
5.
Life Sci ; 234: 116792, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31465733

RESUMO

AIMS: Assisted reproductive technologies (ART) have been widely used to treat infertility, which may impact on fetuses and offspring. This study investigated the effects of in vitro fertilization-embryo transfer (IVF-ET) on angiotensin II (AII)-mediated vasoconstrictions in umbilical cord vein, and explored possible reprogrammed methylation mechanism. MATERIALS AND METHODS: Human umbilical cords were randomly divided into ordinary pregnancy and IVF-ET pregnancy. Vascular studies with AII as well as its specific receptor antagonists losartan and PD123,319 were conducted. Real-time quantitative PCR, Western blotting, and methylation analysis by bisulfite sequencing were performed with the cord vessel samples. KEY FINDINGS: In IVF-ET group, the maximal response to AII in umbilical vessels was significantly greater than that in the ordinary pregnancy. Using losartan and PD123,319, angiotensin receptor subtype 1 (AT1R) was found mainly responsible for the enhanced contraction in the umbilical vein of IVF-ET pregnancy. Decreased mRNA expression of DNMT3A was found in umbilical vein of IVF-ET group. Hypomethylation of the AGTR1 gene (gene encoding AT1R) in the umbilical veins of the IVF group was found. The data suggested that the IVF-ET treatments altered AII-mediated vasoconstrictions in umbilical veins, which could be partially attributed to the increased expression of AT1R. SIGNIFICANCE: The hypo-methylation of the AGTR1 gene caused by IVF-ET might play important roles in altered vasoconstrictions, impacting on cardiovascular systems in the long run.


Assuntos
Angiotensina II/metabolismo , Metilação de DNA , Transferência Embrionária/métodos , Fertilização In Vitro/métodos , Receptor Tipo 1 de Angiotensina/genética , Cordão Umbilical/irrigação sanguínea , Vasoconstrição , Bloqueadores do Receptor Tipo 1 de Angiotensina II/farmacologia , Bloqueadores do Receptor Tipo 2 de Angiotensina II/farmacologia , Anti-Hipertensivos/farmacologia , Transferência Embrionária/efeitos adversos , Feminino , Fertilização In Vitro/efeitos adversos , Humanos , Imidazóis/farmacologia , Losartan/farmacologia , Gravidez , Piridinas/farmacologia , Vasoconstrição/efeitos dos fármacos , Vasoconstritores/farmacologia
6.
J Agric Food Chem ; 67(37): 10498-10504, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31452369

RESUMO

Owing to the changing needs of agriculture, the exploration of new pest control agents remains as critical as ever. The analogues 3a-3v of the natural product cerbinal were synthesized from genipin by an efficient and practical method under additive-free conditions. The antiviral and insecticidal effects of cerbinal and these cyclopenta[c]pyridines (3a-3v) were evaluated systematically. Most of the synthesized compounds exhibited higher anti-TMV activities than the lead compound cerbinal. Compound 3s (2-(4-methoxyphenyl)) had the most promising inhibitory activities against TMV (inactivation effect 49.0 ± 0.8%, curative effect 41.2 ± 4.3%, and protection effect 51.5 ± 2.7% at 500 µg/mL). Among the synthesized compounds, only 3v (2-(2-chloro-4-(trifluoromethoxy)phenyl)) reached the activity level of cerbinal against Plutella xylostella. This suggested that the cyclopenta[c]pyridines obtained by modifications of cerbinal at position 2 are very significant for the anti-TMV activity, and yet were exceptionally less active for the insecticidal activities.


Assuntos
Antivirais/síntese química , Antivirais/farmacologia , Produtos Biológicos/síntese química , Produtos Biológicos/farmacologia , Indenos/química , Indenos/farmacologia , Inseticidas/química , Inseticidas/farmacologia , Animais , Antivirais/química , Produtos Biológicos/química , Descoberta de Drogas , Indenos/síntese química , Inseticidas/síntese química , Iridoides/química , Estrutura Molecular , Mariposas/efeitos dos fármacos , Mariposas/crescimento & desenvolvimento , Piridinas/síntese química , Piridinas/química , Piridinas/farmacologia , Relação Estrutura-Atividade , Vírus do Mosaico do Tabaco/efeitos dos fármacos , Vírus do Mosaico do Tabaco/crescimento & desenvolvimento
7.
J Enzyme Inhib Med Chem ; 34(1): 1426-1438, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31401883

RESUMO

Anaplastic lymphoma kinase (ALK) has been recognised as a promising molecular target of targeted therapy for NSCLC. We performed SAR study of pyrazolo[3,4-b]pyridines to override crizotinib resistance caused by ALK-L1196M mutation and identified a novel and potent L1196M inhibitor, 10g. 10g displayed exceptional enzymatic activities (<0.5 nM of IC50) against ALK-L1196M as well as against ALK-wt. In addition, 10g is an extremely potent inhibitor of ROS1 (<0.5 nM of IC50) and displays excellent selectivity over c-Met. Moreover, 10g strongly suppresses proliferation of ALK-L1196M-Ba/F3 and H2228 cells harbouring EML4-ALK via apoptosis and the ALK signalling blockade. The results of molecular docking studies reveal that, in contrast to crizotinib, 10g engages in a favourable interaction with M1196 in the kinase domain of ALK-L1196M and hydrogen bonding with K1150 and E1210. This SAR study has provided a useful insight into the design of novel and potent inhibitors against ALK gatekeeper mutant.


Assuntos
Quinase do Linfoma Anaplásico/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Pirazóis/farmacologia , Piridinas/farmacologia , Quinase do Linfoma Anaplásico/metabolismo , Apoptose/efeitos dos fármacos , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Linhagem Celular Transformada , Proliferação de Células/efeitos dos fármacos , Cromatografia Líquida , Cristalografia por Raios X , Inibidores Enzimáticos/química , Humanos , Concentração Inibidora 50 , Simulação de Acoplamento Molecular , Espectroscopia de Prótons por Ressonância Magnética , Pirazóis/química , Piridinas/química , Transdução de Sinais/efeitos dos fármacos , Espectrometria de Massas por Ionização por Electrospray , Relação Estrutura-Atividade
8.
Anticancer Res ; 39(7): 3803-3808, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31262907

RESUMO

BACKGROUND: Platinum-based therapy represents the main pharmacological treatment for ovarian carcinoma. Since molecular targeting of receptor tyrosine kinases (RTK) affects factors that may modulate drug response, the aim of this study was to examine whether downstream targets of AXL RTK could be exploited to improve cell response to cisplatin. MATERIALS AND METHODS: Inhibitors of p38 (SB203580) and of signal transducer and activator of transcription 3 (stattic) were employed in combination with cisplatin in ovarian carcinoma cell lines. Apoptosis assay and western blot analysis were performed to evaluate cell response after treatment. RESULTS: SB203580 produced a synergistic effect in combination with cisplatin in cisplatin-resistant IGROV-1/Pt1 cells. In addition, a favorable drug interaction was observed in A2780 cells when pre-incubated with cisplatin prior to stattic. The analysis of cell response after combined treatment showed down-regulation of the pro-apoptotic protein BCL2-associated agonist of cell death (BAD). CONCLUSION: Our results support the notion that downstream targets of AXL in ovarian carcinoma cells can be exploited to increase cisplatin activity in ovarian carcinoma models.


Assuntos
Antineoplásicos/farmacologia , Cisplatino/farmacologia , Imidazóis/farmacologia , Neoplasias Ovarianas/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Piridinas/farmacologia , Receptores Proteína Tirosina Quinases/antagonistas & inibidores , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Linhagem Celular Tumoral , Sinergismo Farmacológico , Feminino , Humanos , Neoplasias Ovarianas/tratamento farmacológico , Proteínas Proto-Oncogênicas/metabolismo , Receptores Proteína Tirosina Quinases/metabolismo , Fator de Transcrição STAT3
9.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 35(6): 545-551, 2019 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-31292059

RESUMO

Objective To illuminate whether IL-17 regulates receptor activator of NF-κB ligand (RANKL) and osteoprotegerin (OPG) expression in human periodontal ligament fibroblasts (HPDLFs) via p38MAPK signaling pathway. Methods HPDLFs were incubated in the presence of 20 ng/mL IL-17 for 0, 20, 40, 60 and 80 minutes. HPDLFs were divided randomly into 6 groups: control group, dimethyl sulfoxide (DMSO) group, p38MAPK pathway inhibitor SB203580 group, IL-17 group, IL-17 combined with DMSO group and IL-17 combined with SB203580 group. SB203580 (10 µmol/L) and IL-17 (20 ng/mL) were added to the corresponding groups. Real-time quantitative PCR was used to detect the expression of RANKL and OPG mRNAs in HPDLFs. The levels of phospho-p38MAPK (p-p38MAPK) and RANKL protein were measured using Western blot analysis. The protein level of OPG was detected by ELISA. Results After IL-17 stimulation, the expression level of p-p38MAPK protein gradually increased starting from 0 minute and reached its highest level at 60 minutes. It started to decline at 80 minutes. Stimulation with IL-17 could increase the mRNA and protein expression level of RANKL but decrease the mRNA and protein expression level of OPG. Nevertheless, unlike the IL-17 group, IL-17 combined with inhibitor SB203580 decreased the expression of RANKL mRNA and protein and increased OPG mRNA. Conclusion IL-17 can enhance the expression of RANKL in human periodontal fibroblasts and inhibit the expression of OPG mRNA through the p38MAPK signal transduction pathways.


Assuntos
Fibroblastos/citologia , Interleucina-17/farmacologia , Sistema de Sinalização das MAP Quinases , Osteoprotegerina/metabolismo , Ligamento Periodontal/citologia , Ligante RANK/metabolismo , Células Cultivadas , Dimetil Sulfóxido/farmacologia , Humanos , Imidazóis/farmacologia , Piridinas/farmacologia , Distribuição Aleatória , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
10.
JAMA ; 321(21): 2101-2112, 2019 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-31162568

RESUMO

Importance: Heart failure with preserved ejection fraction (HFpEF) lacks effective treatments. Based on preclinical studies, neladenoson bialanate, a first-in-class partial adenosine A1 receptor agonist, has the potential to improve several heart failure-related cardiac and noncardiac abnormalities but has not been evaluated to treat HFpEF. Objectives: To determine whether neladenoson improves exercise capacity, physical activity, cardiac biomarkers, and quality of life in patients with HFpEF and to find the optimal dose. Design, Setting, and Participants: Phase 2b randomized clinical trial conducted at 76 centers in the United States, Europe, and Japan. Patients (N = 305) with New York Heart Association class II or III HFpEF with elevated natriuretic peptide levels were enrolled between May 10, 2017, and December 7, 2017 (date of final follow-up: June 20, 2018). Interventions: Participants were randomized (1:2:2:2:2:3) to neladenoson (n = 27 [5 mg], n = 50 [10 mg], n = 51 [20 mg], n = 50 [30 mg], and n = 51 [40 mg]) or matching placebo (n = 76) for 20 weeks of treatment. Main Outcomes and Measures: The primary end point was change in 6-minute walk test distance from baseline to 20 weeks (minimal clinically important difference, 40 m). Key safety measures included bradyarrhythmias and adverse events. To evaluate the effects of varying doses of neladenoson, a multiple comparison procedure with 5 modeling techniques (linear, Emax, 2 variations of sigmoidal Emax, and quadratic) was used to evaluate diverse dose-response profiles. Results: Among 305 patients who were randomized (mean age, 74 years; 160 [53%] women; mean 6-minute walk test distance, 321.5 m), 261 (86%) completed the trial and were included in the primary analysis. After 20 weeks of treatment, the mean absolute changes from baseline in 6-minute walk test distance were 0.2 m (95% CI, -12.1 to 12.4 m) for the placebo group; 19.4 m (95% CI, -10.8 to 49.7 m) for the 5 mg of neladenoson group; 29.4 m (95% CI, 3.0 to 55.8 m) for 10 mg of neladenoson group; 13.8 m (95% CI, -2.3 to 29.8 m) for 20 mg of neladenoson group; 16.3 m (95% CI, -1.1 to 33.6 m) for 30 mg of neladenoson group; and 13.0 m (95% CI, -5.9 to 31.9 m) for 40 mg of neladenoson group. Because none of the neladenoson groups achieved the clinically relevant 40-m increase in 6-minute walk test distance from baseline, an optimal dose of neladenoson was not identified. There was no significant dose-response relationship for the change in 6-minute walk test distance among the 5 different dose-response models (P = .05 for Emax; P = .18 for quadratic; P = .21 for sigmoidal Emax 1; P = .39 for linear; and P = .52 for sigmoidal Emax 2). Serious adverse events were similar among the neladenoson groups (61/229 [26.6%]) and the placebo group (21/76 [27.6%]). Conclusions and Relevance: Among patients with HFpEF, there was no significant dose-response relationship detected for neladenoson with regard to the change in exercise capacity from baseline to 20 weeks. In light of these findings, novel approaches will be needed if further development of neladenoson for the treatment of patients with HFpEF is pursued. Trial Registration: ClinicalTrials.gov Identifier: NCT03098979.


Assuntos
Dipeptídeos/farmacologia , Tolerância ao Exercício/efeitos dos fármacos , Insuficiência Cardíaca/fisiopatologia , Piridinas/farmacologia , Idoso , Idoso de 80 Anos ou mais , Dipeptídeos/administração & dosagem , Dipeptídeos/efeitos adversos , Relação Dose-Resposta a Droga , Feminino , Insuficiência Cardíaca/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade , Consumo de Oxigênio , Piridinas/administração & dosagem , Piridinas/efeitos adversos , Qualidade de Vida , Volume Sistólico , Teste de Caminhada
11.
Nat Commun ; 10(1): 2477, 2019 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-31171770

RESUMO

Blood vessels in the central nervous system (CNS) develop unique features, but the contribution of CNS neurons to regulating those features is not fully understood. We report that inhibiting spontaneous cholinergic activity or reducing starburst amacrine cell numbers prevents invasion of endothelial cells into the deep layers of the retina and causes blood-retinal-barrier (BRB) dysfunction in mice. Vascular endothelial growth factor (VEGF), which drives angiogenesis, and Norrin, a Wnt ligand that induces BRB properties, are decreased after activity blockade. Exogenous VEGF restores vessel growth but not BRB function, whereas stabilizing beta-catenin in endothelial cells rescues BRB dysfunction but not vessel formation. We further identify that inhibiting cholinergic activity reduces angiogenesis during oxygen-induced retinopathy. Our findings demonstrate that neural activity lies upstream of VEGF and Norrin, coordinating angiogenesis and BRB formation. Neural activity originating from specific neural circuits may be a general mechanism for driving regional angiogenesis and barrier formation across CNS development.


Assuntos
Células Amácrinas/fisiologia , Barreira Hematorretiniana/crescimento & desenvolvimento , Neurônios Colinérgicos/fisiologia , Células Endoteliais/fisiologia , Neovascularização Fisiológica/fisiologia , Células Ganglionares da Retina/fisiologia , Animais , Barreira Hematorretiniana/efeitos dos fármacos , Barreira Hematorretiniana/inervação , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Neurônios Colinérgicos/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Proteínas do Olho/metabolismo , Camundongos , Proteínas do Tecido Nervoso/metabolismo , Agonistas Nicotínicos/farmacologia , Oxigênio/efeitos adversos , Piridinas/farmacologia , Doenças Retinianas , Células Ganglionares da Retina/metabolismo , Neovascularização Retiniana/etiologia , Tetrodotoxina/farmacologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , beta Catenina/metabolismo
12.
Pestic Biochem Physiol ; 157: 19-25, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31153468

RESUMO

Piericidin A (PIA), an active inhibitor of Complex I, is widely used in studies of the anti-bacterial and anti-disease competence, but its physiological and mechanistic effects have rarely been clearly defined in insect individual or insect cells. The present study reveals the considerable insecticidal activity of PIA on Mythimna separata larvae by using a comparison with Aphis craccivora adult, and the cytotoxic selectivity induced by PIA on lepidopteran Tn5B1-4 cells. We demonstrate that the viability of Tn5B1-4 cells is inhibited by PIA in a time- and concentration-dependent manner with IC50 value of 0.061 µM, whilst PIA shows slight inhibitory effect on the viability of HepG2 and Hek293 cells with IC50 value of 233.97 and 228.96 µM, respectively. The inhibitory effect of PIA on the proliferation of Tn5B1-4 cells is significant and persistent, causing a series of morphological changes including cell shrinkage, condensed and fragmented nuclei. Intracellular biochemical assays show that PIA induces apoptosis of Tn5B1-4 cells coincides with a decrease in the mitochondrial membrane potential. PIA in Tn5B1-4 cells can be chelated by EDTA, thereby losing cytotoxicity, whereas exogenous Ca2+ restores the cytotoxicity of PIA by chelating with EDTA in a competitive manner. Our findings highlight the importance of the long-lasting cytotoxicity and the cytoxic selectivity on Tn5B1-4 cells caused by PIA, which ensure the identification of insecticidal effect of PIA against insect pests.


Assuntos
Apoptose/efeitos dos fármacos , Inseticidas/farmacologia , Larva/efeitos dos fármacos , Lepidópteros/efeitos dos fármacos , Piridinas/farmacologia , Animais , Sobrevivência Celular/efeitos dos fármacos , Citometria de Fluxo , Células HEK293 , Células Hep G2 , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos
13.
Pestic Biochem Physiol ; 157: 204-210, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31153470

RESUMO

Sulfoxaflor is the first commercially available sulfoximine insecticide, which exhibits highly efficacy against many sap-feeding insect pests and has been applied as an alternative insecticide against cotton aphid in China. This study was conducted to investigate the risk of resistance development, the cross-resistance pattern and the potential resistance mechanisms of sulfoxaflor in Aphis gossypii. A colony (SulR strain) of A. gossypii with 245-fold resistance, originated from Xinjiang field population, was established by continuous selection using sulfoxaflor. The SulR strain has developed cross-resistance to imidacloprid (80.8-fold), acetamiprid (19.3-fold), thiamethoxam (10.0-fold), and flupyradifurone (107.5-fold), while no cross-resistance was detected to malathion, omethoate, bifenthrin, methomyl, and carbosulfan. Piperonyl butoxide and S, S, S-tributyl phosphorotrithioate could significantly increase the toxicity of sulfoxaflor to the SulR strain by 5.99- and 4.18-fold, respectively, whereas no synergistic effect with diethyl maleate was observed. The activities of P450s and carboxylesterase were significantly higher in the SulR strain than that in the SS strain. Further gene expression determination demonstrated that nine P450 genes were significantly increased in SulR strain and suppression the expression of CYP6CY13 and CYP6CY19 by RNAi significantly increased the susceptibility of SulR adult aphids to sulfoxaflor. These results demonstrated that the enhancing detoxification by cytochrome P450 monooxygenase may be involved in A.gossypii resistance to sulfoxaflor.


Assuntos
Afídeos/efeitos dos fármacos , Sistema Enzimático do Citocromo P-450/metabolismo , Piridinas/farmacologia , Compostos de Enxofre/farmacologia , 4-Butirolactona/análogos & derivados , 4-Butirolactona/farmacologia , Animais , Afídeos/genética , Afídeos/metabolismo , Sistema Enzimático do Citocromo P-450/genética , Resistência a Inseticidas/genética , Inseticidas/farmacologia , Neonicotinoides/farmacologia , Nitrocompostos/farmacologia , Piretrinas/farmacologia
14.
Pestic Biochem Physiol ; 157: 26-32, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31153474

RESUMO

Nitenpyram is very effective in controlling Nilaparvata lugens (brown planthopper, BPH), and its resistance has been reported in field populations; however, the resistance mechanism remains unclear. In the present study, cross-resistance and resistance mechanisms in nitenpyram-resistant BPH were investigated. A resistant strain (NR) with a high resistance level (164.18-fold) to nitenpyram was evolved through successive selection for 42 generations from a laboratory susceptible strain (NS). The bioassay results showed that the NR exhibited cross-resistance to imidacloprid (37.46-fold), thiamethoxam (71.66-fold), clothianidin (149.17-fold), dinotefuran (98.13-fold), sulfoxaflor (47.24-fold), cycloxaprid (9.33-fold), etofenprox (10.51-fold) and isoprocarb (9.97-fold) but not to triflumezopyrim, chlorpyrifos and buprofezin. The NR showed a 3.21-fold increase in cytochrome P450 monooxygenase (P450) activity compared to that in the NS, while resistance was also synergized (4.03-fold) with the inhibitor piperonyl butoxide (PBO), suggesting a role of P450. Furthermore, the mRNA expression levels of cytochrome P450 (CYP) genes by quantitative real-time PCR results indicated that twelve P450 genes were significantly overexpressed in the NR strain, especially CYP6ER1 (203.22-fold). RNA interference (RNAi) suppression of CYP6ER1 through injection of dsCYP6ER1 led to significant susceptibility in the NR strain. The current study expands our understanding of the nitenpyram resistance mechanism in N. lugens, provides an important reference for integrated pest management (IPM), and enriches the theoretical system of insect toxicology.


Assuntos
Hemípteros/efeitos dos fármacos , Neonicotinoides/farmacologia , Animais , Carbamatos/farmacologia , Guanidinas/farmacologia , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Resistência a Inseticidas , Nitrocompostos/farmacologia , Piretrinas/farmacologia , Piridinas/farmacologia , Pirimidinonas/farmacologia , Interferência de RNA , Tiazóis/farmacologia
15.
Nat Commun ; 10(1): 2746, 2019 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-31227712

RESUMO

Nicotinic acetylcholine receptors (nAChRs) mediate and modulate synaptic transmission throughout the brain, and contribute to learning, memory, and behavior. Dysregulation of α7-type nAChRs in neuropsychiatric as well as immunological and oncological diseases makes them attractive targets for pharmaceutical development. Recently, we identified NACHO as an essential chaperone for α7 nAChRs. Leveraging the robust recombinant expression of α7 nAChRs with NACHO, we utilized genome-wide cDNA library screening and discovered that several anti-apoptotic Bcl-2 family proteins further upregulate receptor assembly and cell surface expression. These effects are mediated by an intracellular motif on α7 that resembles the BH3 binding domain of pro-apoptotic Bcl-2 proteins, and can be blocked by BH3 mimetic Bcl-2 inhibitors. Overexpression of Bcl-2 member Mcl-1 in neurons enhanced surface expression of endogenous α7 nAChRs, while a combination of chemotherapeutic Bcl2-inhibitors suppressed neuronal α7 receptor assembly. These results demonstrate that Bcl-2 proteins link α7 nAChR assembly to cell survival pathways.


Assuntos
Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , Neurônios/metabolismo , Receptor Nicotínico de Acetilcolina alfa7/metabolismo , Motivos de Aminoácidos/genética , Animais , Benzotiazóis/farmacologia , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Células HEK293 , Humanos , Isoquinolinas/farmacologia , Chaperonas Moleculares/metabolismo , Mutação , Proteína de Sequência 1 de Leucemia de Células Mieloides/antagonistas & inibidores , Neurônios/efeitos dos fármacos , Agonistas Nicotínicos/farmacologia , Cultura Primária de Células , Ligação Proteica/efeitos dos fármacos , Piridinas/farmacologia , Pirimidinas/farmacologia , Ratos , Transmissão Sináptica/efeitos dos fármacos , Tiofenos/farmacologia , Regulação para Cima , Receptor Nicotínico de Acetilcolina alfa7/genética
16.
Cell Prolif ; 52(4): e12637, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31168899

RESUMO

OBJECTIVES: Chondrocyte proliferation and differentiation are crucial for endochondral ossification, but their regulatory mechanism remains unclear. The present study aimed to determine the physiological function of TGFß1 signalling in the proliferation and differentiation of antler chondrocytes and explore its relationship with Notch, Shh signalling and Foxa. MATERIALS AND METHODS: Immunofluorescence, Western blot, MTS assay, flow cytometry, RNA interference and real-time PCR were used to analyse the function and regulatory mechanisms of TGFß1 signalling in antler chondrocyte proliferation and differentiation. RESULTS: TGFß1, TGFBR1 and TGFBR2 were highly expressed in antler cartilage. TGFß1 promoted chondrocyte proliferation, increased the proportion of S-phase cells and induced the expression of hypertrophic chondrocyte markers Col X, Runx2 and Alpl. However, this induction was weakened by TGFß receptor inhibitor SB431542 and Smad3 inhibitor SIS3. Simultaneously, TGFß1 activated Notch and Shh signalling whose blockage attenuated the above effects of rTGFß1, whereas addition of rShh rescued the defects in chondrocyte proliferation and differentiation elicited by SB431542 and SIS3. Further analysis revealed that inhibition of Notch signalling impeded TGFß1 activation of the Shh pathway. Knockdown of Foxa1, Foxa2 and Foxa3 abrogated the effects of TGFß1 on chondrocyte differentiation. Notch and Shh signalling mediated the regulation of Foxa transcription factors by TGFß1. CONCLUSIONS: TGFß1 signalling could induce the proliferation and differentiation of antler chondrocytes through Notch-Shh-Foxa pathway.


Assuntos
Diferenciação Celular/fisiologia , Proliferação de Células/fisiologia , Transdução de Sinais/fisiologia , Fator de Crescimento Transformador beta1/metabolismo , Animais , Chifres de Veado , Benzamidas/farmacologia , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Condrócitos/efeitos dos fármacos , Condrócitos/metabolismo , Dioxóis/farmacologia , Proteínas Hedgehog/metabolismo , Fator 3-alfa Nuclear de Hepatócito/metabolismo , Isoquinolinas/farmacologia , Piridinas/farmacologia , Pirróis/farmacologia , Receptores Notch/metabolismo , Fase S/efeitos dos fármacos , Fase S/fisiologia , Transdução de Sinais/efeitos dos fármacos
17.
Toxicol Lett ; 313: 1-10, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31170421

RESUMO

The constitutive androstane receptor(CAR) activation is connected with mitogenic effects leading to liver hyperplasia and tumorigenesis in rodents. CAR activators, including phenobarbital, are considered rodent non-genotoxic carcinogens. Recently, trans-3,4,5,4´-tetramethoxystilbene(TMS), a potential anticancer drug (DMU-212), have been shown to alleviate N-nitrosodiethylamine/phenobarbital-induced liver carcinogenesis. We studied whether TMS inhibits mouse Car to protect from the PB-induced tumorigenesis. Unexpectedly, we identified TMS as a murine CAR agonist in reporter gene experiments, in mouse hepatocytes, and in C57BL/6 mice in vivo. TMS up-regulated Car target genes Cyp2b10, Cyp2c29 and Cyp2c55 mRNAs, but down-regulated expression of genes involved in gluconeogenesis and lipogenesis. TMS did not change or down-regulate genes involved in liver proliferation or apoptosis such as Mki67, Foxm1, Myc, Mcl1, Pcna, Bcl2, or Mdm2, which were up-regulated by another Car ligand TCPOBOP. TMS did not increase liver weight and had no significant effect on Ki67 and Pcna labeling indices in mouse liver in vivo. In murine hepatic AML12 cells, we confirmed a Car-independent proapoptotic effect of TMS. We conclude that TMS is a Car ligand with limited effects on hepatocyte proliferation, likely due to promoting apoptosis in mouse hepatic cells, while controlling Car target genes involved in xenobiotic and endobiotic metabolism.


Assuntos
Anticarcinógenos/farmacologia , Proliferação de Células/efeitos dos fármacos , Hepatócitos/efeitos dos fármacos , Neoplasias Hepáticas/prevenção & controle , Fígado/efeitos dos fármacos , Receptores Citoplasmáticos e Nucleares/agonistas , Estilbenos/farmacologia , Animais , Anticarcinógenos/metabolismo , Apoptose/efeitos dos fármacos , Hidrocarboneto de Aril Hidroxilases/genética , Hidrocarboneto de Aril Hidroxilases/metabolismo , Sítios de Ligação , Família 2 do Citocromo P450/genética , Família 2 do Citocromo P450/metabolismo , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Gluconeogênese/efeitos dos fármacos , Gluconeogênese/genética , Células Hep G2 , Hepatócitos/metabolismo , Hepatócitos/patologia , Humanos , Lipogênese/efeitos dos fármacos , Lipogênese/genética , Fígado/metabolismo , Neoplasias Hepáticas/enzimologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Masculino , Camundongos Endogâmicos C57BL , Simulação de Acoplamento Molecular , Ligação Proteica , Piridinas/farmacologia , Receptores Citoplasmáticos e Nucleares/genética , Receptores Citoplasmáticos e Nucleares/metabolismo , Transdução de Sinais/efeitos dos fármacos , Esteroide Hidroxilases/genética , Esteroide Hidroxilases/metabolismo , Estilbenos/metabolismo
18.
Cancer Sci ; 110(8): 2549-2557, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31162771

RESUMO

Cancer treatment, especially that for breast and lung cancer, has entered a new era and continues to evolve, with the development of genome analysis technology and the advent of molecular targeted drugs including tyrosine kinase inhibitors. Nevertheless, acquired drug resistance to molecular targeted drugs is unavoidable, creating a clinically challenging problem. We recently reported the antitumor effect of a pan-HER inhibitor, afatinib, against human epidermal growth factor receptor 2 (HER2)-amplified gastric cancer cells. The purpose of the present study was to identify the mechanisms of acquired afatinib resistance and to investigate the treatment strategies for HER2-amplified gastric cancer cells. Two afatinib-resistant gastric cancer cell lines were established from 2 HER2-amplified cell lines, N87 and SNU216. Subsequently, we investigated the molecular profiles of resistant cells. The activation of the HER2 pathway was downregulated in N87-derived resistant cells, whereas it was upregulated in SNU216-derived resistant cells. In the N87-derived cell line, both MET and AXL were activated, and combination treatment with afatinib and cabozantinib, a multikinase inhibitor that inhibits MET and AXL, suppressed the cell growth of cells with acquired resistance both in vitro and in vivo. In the SNU216-derived cell line, YES1, which is a member of the Src family, was remarkably activated, and dasatinib, a Src inhibitor, exerted a strong antitumor effect in these cells. In conclusion, we identified MET and AXL activation in addition to YES1 activation as novel mechanisms of afatinib resistance in HER2-driven gastric cancer. Our results also indicated that treatment strategies targeting individual mechanisms of resistance are key to overcoming such resistance.


Assuntos
Afatinib/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Receptor ErbB-2/genética , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/genética , Anilidas/farmacologia , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/genética , Camundongos , Proteínas Proto-Oncogênicas c-yes/genética , Piridinas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/genética , Ensaios Antitumorais Modelo de Xenoenxerto , Quinases da Família src/genética
19.
Eur J Med Chem ; 177: 316-337, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31158747

RESUMO

Residues in the histone substrate binding sites that differ between the KDM4 and KDM5 subfamilies were identified. Subsequently, a C8-substituted pyrido[3,4-d]pyrimidin-4(3H)-one series was designed to rationally exploit these residue differences between the histone substrate binding sites in order to improve affinity for the KDM4-subfamily over KDM5-subfamily enzymes. In particular, residues E169 and V313 (KDM4A numbering) were targeted. Additionally, conformational restriction of the flexible pyridopyrimidinone C8-substituent was investigated. These approaches yielded potent and cell-penetrant dual KDM4/5-subfamily inhibitors including 19a (KDM4A and KDM5B Ki = 0.004 and 0.007 µM, respectively). Compound cellular profiling in two orthogonal target engagement assays revealed a significant reduction from biochemical to cell-based activity across multiple analogues; this decrease was shown to be consistent with 2OG competition, and suggests that sub-nanomolar biochemical potency will be required with C8-substituted pyrido[3,4-d]pyrimidin-4(3H)-one compounds to achieve sub-micromolar target inhibition in cells.


Assuntos
Inibidores Enzimáticos/farmacologia , Histona Desmetilases com o Domínio Jumonji/antagonistas & inibidores , Piridinas/farmacologia , Pirimidinonas/farmacologia , Linhagem Celular Tumoral , Cristalografia por Raios X , Ensaios de Seleção de Medicamentos Antitumorais/métodos , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Inibidores Enzimáticos/metabolismo , Humanos , Interações Hidrofóbicas e Hidrofílicas , Histona Desmetilases com o Domínio Jumonji/química , Histona Desmetilases com o Domínio Jumonji/metabolismo , Estrutura Molecular , Ligação Proteica , Piridinas/síntese química , Piridinas/química , Piridinas/metabolismo , Pirimidinonas/síntese química , Pirimidinonas/química , Pirimidinonas/metabolismo , Relação Estrutura-Atividade
20.
Eur J Med Chem ; 178: 141-153, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31177074

RESUMO

Anaplastic lymphoma kinase (ALK) is a receptor tyrosine kinase responsible for development of various tumor types. In this study, we synthesized a series of novel 2,4-diarylaminopyrimidine derivatives possessing a unique N-(3-pyridinylmethyl)urea moiety as ALK inhibitors. The most promising analog 5m bearing a 3-methoxy-4-morpholinophenyl substituent significantly inhibited proliferation of ALK positive H3122 and Karpas-299 cells with IC50 values about 10 nM, which were comparable with positive control LDK378. Compound 5m suppressed phosphorylation of ALK and its downstream proteins, and showed low cytotoxicity on normal human primary fibroblast cells (BJ cells). The binding mode of 5m was proposed by docking simulation, which explains the important role of N-(3-pyridinylmethyl)urea moiety. Furthermore, compound 5m exhibited favorable liver microsomal stability and significant efficacy in H3122 xenograft mice model. Interestingly, compound 5m also showed broader anti-proliferative activity on other human tumor cell lines, which was different from other ALK inhibitors.


Assuntos
Quinase do Linfoma Anaplásico/antagonistas & inibidores , Antineoplásicos/uso terapêutico , Compostos de Fenilureia/uso terapêutico , Inibidores de Proteínas Quinases/uso terapêutico , Piridinas/uso terapêutico , Pirimidinas/uso terapêutico , Adenocarcinoma de Pulmão/tratamento farmacológico , Quinase do Linfoma Anaplásico/química , Animais , Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Antineoplásicos/toxicidade , Sítios de Ligação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Estabilidade de Medicamentos , Feminino , Fibroblastos/efeitos dos fármacos , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Camundongos Endogâmicos BALB C , Microssomos Hepáticos/metabolismo , Simulação de Acoplamento Molecular , Estrutura Molecular , Compostos de Fenilureia/síntese química , Compostos de Fenilureia/farmacologia , Compostos de Fenilureia/toxicidade , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/toxicidade , Piridinas/síntese química , Piridinas/farmacologia , Piridinas/toxicidade , Pirimidinas/síntese química , Pirimidinas/farmacologia , Pirimidinas/toxicidade , Relação Estrutura-Atividade , Ensaios Antitumorais Modelo de Xenoenxerto
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