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1.
Antiviral Res ; 195: 105193, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34687820

RESUMO

Transient receptor potential mucolipin 2 and 3 (TRPML2 and TRPML3), as key channels in the endosomal-lysosomal system, are associated with many different cellular processes, including ion release, membrane trafficking and autophagy. In particular, they can also facilitate viral entry into host cells and enhance viral infection. We previously identified that two selective TRPML agonists, ML-SA1 and SN-2, that showed antiviral activities against dengue virus type 2 (DENV2) and Zika virus (ZIKV) in vitro, but their antiviral mechanisms are still elusive. Here, we reported that ML-SA1 could inhibit DENV2 replication by downregulating the expression of both TRPML2 and TRPML3, while the other TRPML activator, SN-2, suppressed DENV2 infection by reducing only TRPML3 expression. Consistently, the channel activities of both TRPML2 and TRPML3 were also found to be associated with the antiviral activity of ML-SA1 on DENV2 and ZIKV, but SN-2 relied only on TRPML3 channel activity. Further mechanistic experiments revealed that ML-SA1 and SN-2 decreased the expression of the late endosomal marker Rab7, dependent on TRPML2 and TRPML3, indicating that these two compounds likely inhibit viral infection by promoting vesicular trafficking from late endosomes to lysosomes and then accelerating lysosomal degradation of the virus. As expected, neither ML-SA1 nor SN-2 inhibited herpes simplex virus type I (HSV-1), whose entry is independent of the endolysosomal network. Together, our work reveals the antiviral mechanisms of ML-SA1 and SN-2 in targeting TRPML channels, possibly leading to the discovery of new drug candidates to inhibit endocytosed viruses.

2.
Toxins (Basel) ; 13(9)2021 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-34564614

RESUMO

Thermally processed Buthus martensii Karsch scorpions are a traditional Chinese medical material for treating various diseases. However, their pharmacological foundation remains unclear. Here, a new degraded peptide of scorpion toxin was identified in Chinese scorpion medicinal material by proteomics. It was named BmK86-P1 and has six conserved cysteine residues. Homology modeling and circular dichroism spectra experiments revealed that BmK86-P1 not only contained representative disulfide bond-stabilized α-helical and ß-sheet motifs but also showed remarkable stability at test temperatures from 20-95 °C. Electrophysiology experiments indicated that BmK86-P1 was a highly potent and selective inhibitor of the hKv1.2 channel with IC50 values of 28.5 ± 6.3 nM. Structural and functional dissection revealed that two residues of BmK86-P1 (i.e., Lys19 and Ile21) were the key residues that interacted with the hKv1.2 channel. In addition, channel chimeras and mutagenesis experiments revealed that three amino acids (i.e., Gln357, Val381 and Thr383) of the hKv1.2 channel were responsible for BmK86-P1 selectivity. This research uncovered a new bioactive peptide from traditional Chinese scorpion medicinal material that has desirable thermostability and Kv1.2 channel-specific activity, which strongly suggests that thermally processed scorpions are novel peptide resources for new drug discovery for the Kv1.2 channel-related ataxia and epilepsy diseases.

3.
FEBS Lett ; 595(19): 2447-2462, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34387860

RESUMO

The NLRP3 inflammasome, a critical component of the innate immune system, induces caspase-1 activation and interleukin-1ß maturation and drives cell fate toward pyroptosis. However, the mechanism of NLRP3 inflammasome activation still remains elusive. Here we provide evidence that AKT regulates NLRP3 inflammasome activation. Upon NLRP3 activation, AKT activity is inhibited by second stimulus-induced reactive oxygen species. In contrast, AKT activation leads to NLRP3 inhibition and improved mitochondrial fitness. Mechanistically, AKT induces the phosphorylation of the DDX3X (DEAD-box helicase 3, X-linked), a recently identified NLRP3 inflammasome component, and impairs the interaction between DDX3X and NLRP3. Furthermore, an AKT agonist reduces NLRP3-dependent inflammation in two in vivo models of LPS-induced sepsis and Alum-induced peritonitis. Altogether, our study highlights an important role of AKT in controlling NLRP3 inflammasome activation.


Assuntos
RNA Helicases DEAD-box/metabolismo , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , Linhagem Celular , Gliceraldeído-3-Fosfato Desidrogenase (Fosforiladora) , Humanos , Camundongos
4.
Toxicon ; 200: 198-202, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34390711

RESUMO

The scorpion venom system plays a critical role in capturing prey and defending against predators. In this study, the rapid developmental process of the first instar telson was first presented. The small amount of venom in the first instar could be stored well by the distorted and blocked venom ducts, which disappeared in the older scorpions. This special developmental process of the first instar telson revealed the notable survival ability of scorpions.


Assuntos
Venenos de Escorpião , Escorpiões , Animais , Venenos de Escorpião/toxicidade
5.
Int J Biol Sci ; 17(9): 2348-2355, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34239361

RESUMO

Coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has led to more than 150 million infections and about 3.1 million deaths up to date. Currently, drugs screened are urgently aiming to block the infection of SARS-CoV-2. Here, we explored the interaction networks of kinase and COVID-19 crosstalk, and identified phosphoinositide 3-kinase (PI3K)/AKT pathway as the most important kinase signal pathway involving COVID-19. Further, we found a PI3K/AKT signal pathway inhibitor capivasertib restricted the entry of SARS-CoV-2 into cells under non-cytotoxic concentrations. Lastly, the signal axis PI3K/AKT/FYVE finger-containing phosphoinositide kinase (PIKfyve)/PtdIns(3,5)P2 was revealed to play a key role during the cellular entry of viruses including SARS-CoV-2, possibly providing potential antiviral targets. Altogether, our study suggests that the PI3K/AKT kinase inhibitor drugs may be a promising anti-SARS-CoV-2 strategy for clinical application, especially for managing cancer patients with COVID-19 in the pandemic era.


Assuntos
COVID-19/tratamento farmacológico , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Pirimidinas/uso terapêutico , Pirróis/uso terapêutico , SARS-CoV-2/efeitos dos fármacos , Internalização do Vírus/efeitos dos fármacos , Animais , COVID-19/enzimologia , Chlorocebus aethiops , Simulação por Computador , Humanos , Neoplasias/enzimologia , Neoplasias/mortalidade , Proteínas Proto-Oncogênicas c-akt/metabolismo , Pirimidinas/farmacologia , Pirróis/farmacologia , Receptor Cross-Talk , Células Vero
6.
J Biochem Mol Toxicol ; 35(8): e22831, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34155709

RESUMO

Hepatocellular carcinoma (HCC) is considered one of the most common primary liver cancers and the second leading cause of cancer-associated mortality around the world annually. Therefore, it is urgent to develop novel drugs for HCC therapy. We synthesized a novel 4-substituted-methoxybenzoyl-aryl-thiazole (SMART) analog, (5-(4-aminopiperidin-1-yl)-2-phenyl-2H-1,2,3-triazol-4-yl) (3,4,5-trimethoxyphenyl) methanone (W436), with higher solubility, stability, and antitumor activity than SMART against HCC cells in vivo. The purpose of this study was to investigate the mechanisms by which W436 inhibited cell growth in HCC cells. We observed that W436 inhibited the proliferation of HepG2 and Hep3B cells in a dose-dependent manner. Importantly, the anticancer activity of W436 against HCC cells was even higher than that of SMART in vivo. In addition, the antiproliferative effects of W436 on HCC cells were associated with G2/M cell cycle arrest and apoptosis via the activation of reactive oxygen species-mediated mitochondrial apoptotic pathway. W436 also induced protective autophagy by inhibiting the protein kinase B/mammalian target of rapamycin pathway. At the same time, W436 treatment inhibited the cell adhesion and invasion as well as the process of epithelial-to-mesenchymal transition Taken together, our results showed that W436 had the promising potential for the therapeutic treatment of HCC with improved solubility, stability, and bioavailability.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Carcinoma Hepatocelular , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Neoplasias Hepáticas , Pontos de Checagem da Fase M do Ciclo Celular/efeitos dos fármacos , Antineoplásicos/síntese química , Antineoplásicos/química , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia
7.
Int J Biol Macromol ; 178: 143-153, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33636268

RESUMO

Novel degraded potassium channel-modulatory peptides were recently found in thermally processed scorpions, but their pharmacological properties remain unclear. Here, we identified a full-length scorpion toxin (i.e., BmKcug2) and its four truncated analogs (i.e., BmKcug2-P1, BmKcug2-P2, BmKcug2-P3 and BmKcug2-P4) with three conserved disulfide bonds in processed scorpion medicinal material by mass spectrometry. The pharmacological experiments revealed that the recombinant BmKcug2 and BmKcug2-P1 could selectively inhibit the human Kv1.2 and human Kv1.3 potassium channels, while the other three analogs showed a much weaker inhibitory effect on potassium channels. BmKcug2 inhibited hKv1.2 and hKv1.3 channels, with IC50 values of 45.6 ± 5.8 nM and 215.2 ± 39.7 nM, respectively, and BmKcug2-P1 inhibited hKv1.2 and hKv1.3, with IC50 values of 89.9 ± 9.6 nM and 1142.4 ± 64.5 nM, respectively. The chromatographic analysis and pharmacological properties of BmKcug2 and BmKcug2-P1 boiled in water for different times further strongly supported their good thermal stability. Structural and functional dissection indicated that one amino acid, i.e., Tyr36, determined the differential affinities of BmKcug2 and four BmKcug2 analogs. Altogether, this research investigated the different pharmacological properties of BmKcug2 and its truncated analogs, and the findings highlighted the diversity of K+ channel blockers from various scorpion species through thermal processing.


Assuntos
Canal de Potássio Kv1.2/metabolismo , Canal de Potássio Kv1.3/metabolismo , Bloqueadores dos Canais de Potássio/farmacologia , Venenos de Escorpião/farmacologia , Animais , Células HEK293 , Humanos , Escorpiões
8.
J Enzyme Inhib Med Chem ; 36(1): 549-560, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33522315

RESUMO

A series of 1-aryl-5-(4-arylpiperazine-1-carbonyl)-1H-tetrazols as microtubule destabilizers were designed, synthesised and evaluated for anticancer activity. Based on bioisosterism, we introduced the tetrazole moiety containing the hydrogen-bond acceptors as B-ring of XRP44X analogues. The key intermediates ethyl 1-aryl-1H-tetrazole-5-carboxylates 10 can be simply and efficiently prepared via a microwave-assisted continuous operation process. Among the compounds synthesised, compound 6-31 showed noteworthy potency against SGC-7901, A549 and HeLa cell lines. In mechanism studies, compound 6-31 inhibited tubulin polymerisation and disorganised microtubule in SGC-7901 cells by binding to tubulin. Moreover, compound 6-31 arrested SGC-7901cells in G2/M phase. This study provided a new perspective for development of antitumor agents that target tubulin.


Assuntos
Antineoplásicos/farmacologia , Desenho de Fármacos , Microtúbulos/efeitos dos fármacos , Tetrazóis/farmacologia , Moduladores de Tubulina/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Microtúbulos/metabolismo , Micro-Ondas , Modelos Moleculares , Estrutura Molecular , Polimerização/efeitos dos fármacos , Relação Estrutura-Atividade , Tetrazóis/síntese química , Tetrazóis/química , Tubulina (Proteína)/metabolismo , Moduladores de Tubulina/síntese química , Moduladores de Tubulina/química , Células Tumorais Cultivadas
9.
Eur J Pharmacol ; 895: 173867, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33460617

RESUMO

Over the past decade, there has been sustained research activity on programmed death-1/programmed death-ligand 1 (PD-1/PD-L1) immune checkpoint inhibitors for breast cancer (BC) immunotherapy. Several clinical studies have demonstrated the anti-tumor efficacy of monotherapy drugs targeting PD-1 and PD-L1 checkpoint signaling in BC. Besides, the combination of anti-PD-1/PD-L1 agents with other inhibitors, including poly-adenosine diphosphate-ribose polymerase (PARP) inhibitors, vaccines, mitogen-activated protein kinase (MEK) inhibitors, and cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) inhibitors are being investigated to improve drug efficacy. These trials have performed well and have shown better and more sustainable therapeutic responses. As follows, the purpose of this review is to discuss the recent advances in BC immunotherapy targeting the inhibition of PD-1/PD-L1 immune checkpoint signaling, when recommended as a monotherapy or in conjunction with other treatments. We look forward to providing new insights into the current state of BC research and the future direction of PD-1/PD-L1 immune checkpoint signaling.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Antígeno B7-H1/antagonistas & inibidores , Neoplasias da Mama/tratamento farmacológico , Inibidores de Checkpoint Imunológico/uso terapêutico , Imunoterapia , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Antígeno B7-H1/metabolismo , Neoplasias da Mama/imunologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Feminino , Humanos , Inibidores de Checkpoint Imunológico/efeitos adversos , Imunoterapia/efeitos adversos , Terapia de Alvo Molecular , Receptor de Morte Celular Programada 1/metabolismo , Transdução de Sinais , Resultado do Tratamento , Microambiente Tumoral
10.
FASEB J ; 35(2): e20995, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32910509

RESUMO

Virus entry into cells is the initial stage of infection and involves multiple steps, and interfering viral entry represents potential antiviral approaches. Ion channels are pore-forming membrane proteins controlling cellular ion homeostasis and regulating many physiological processes, but their roles during viral infection have rarely been explored. Here, the functional Kv1.3 ion channel was found to be expressed in human hepatic cells and tissues. The Kv1.3 was then revealed to restrict HCV entry via inhibiting endosome acidification-mediated viral membrane fusion. The Kv1.3 was also demonstrated to inhibit DENV and ZIKV with an endosome acidification-dependent entry, but have no effect on SeV with a neutral pH penetration. A Kv1.3 antagonist PAP-1 treatment accelerated animal death in ZIKV-infected Ifnar1-/- mice. Moreover, Kv1.3-deletion was found to promote weight loss and reduce survival rate in ZIKV-infected Kv1.3-/- mice. Altogether, the Kv1.3 ion channel behaves as a host factor restricting viral entry. These findings broaden understanding about ion channel biology.


Assuntos
Vírus da Dengue/fisiologia , Dengue/metabolismo , Hepacivirus/fisiologia , Hepatite C/metabolismo , Canal de Potássio Kv1.3/metabolismo , Infecções por Respirovirus/metabolismo , Vírus Sendai/fisiologia , Internalização do Vírus , Infecção por Zika virus/metabolismo , Zika virus/fisiologia , Animais , Chlorocebus aethiops , Dengue/virologia , Endossomos/metabolismo , Ficusina/farmacologia , Células HEK293 , Hepatite C/virologia , Humanos , Concentração de Íons de Hidrogênio , Canal de Potássio Kv1.3/antagonistas & inibidores , Canal de Potássio Kv1.3/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Infecções por Respirovirus/virologia , Transfecção , Células Vero , Internalização do Vírus/efeitos dos fármacos , Infecção por Zika virus/virologia
11.
J Biochem Mol Toxicol ; 35(3): e22666, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33140567

RESUMO

It is a well-known fact that 60%-85% of anaplastic large cell lymphoma (ALCL) is mainly driven by the anaplastic lymphoma kinase (ALK) fusion protein. Although ALK-positive ALCL patients respond significantly to ALK inhibitors, the development of resistance is inevitable, which requires the development of new therapeutic strategies for ALK-positive ALCL. Here, we investigated the anticancer activities of N-(2((5-chloro-2-((2-methoxy-6-(4-methylpiperazin-1-yl)pyridin-3yl)amino)pyrimidin-4-yl)amino)phenyl)methanesulfonamide (ZX-29), a newly synthesized ALK inhibitor, against nucleophosmin-ALK-positive cell line Karpas299. We demonstrated that ZX-29 decreased Karpas299 cells growth and had better cytotoxicity than ceritinib, which was mediated through downregulating the expression of ALK and related proteins, inducing cell cycle arrest, and promoting cell apoptosis. Moreover, ZX-29-induced cell apoptosis by inducing endoplasmic reticulum stress (ERS). In addition, ZX-29 increased the generation of reactive oxygen species (ROS), and cells pretreatment with N-acetyl- l-cysteine could attenuate ZX-29-induced cell apoptosis and ERS. Taken together, ZX-29 inhibited Karpas299 cell proliferation and induced apoptosis through inhibiting ALK and its downstream protein expression and inducing ROS-mediated ERS. Therefore, our results provide evidence for a novel antitumor candidate for the further investigation.


Assuntos
Quinase do Linfoma Anaplásico/antagonistas & inibidores , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Linfoma Anaplásico de Células Grandes/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Células A549 , Quinase do Linfoma Anaplásico/metabolismo , Células HEK293 , Humanos , Linfoma Anaplásico de Células Grandes/metabolismo , Linfoma Anaplásico de Células Grandes/patologia
13.
J Allergy Clin Immunol ; 147(6): 2236-2248.e16, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33358893

RESUMO

BACKGROUND: Tick bites severely threaten human health because they allow the transmission of many deadly pathogens, including viruses, bacteria, protozoa, and helminths. Pruritus is a leading symptom of tick bites, but its molecular and neural bases remain elusive. OBJECTIVES: This study sought to discover potent drugs and targets for the specific prevention and treatment of tick bite-induced pruritus and arthropod-related itch. METHODS: We used live-cell calcium imaging, patch-clamp recordings, and genetic ablation and evaluated mouse behavior to investigate the molecular and neural bases of tick bite-induced pruritus. RESULTS: We found that 2 tick salivary peptides, IP defensin 1 (IPDef1) and IR defensin 2 (IRDef2), induced itch in mice. IPDef1 was further revealed to have a stronger pruritogenic potential than IRDef2 and to induce pruritus in a histamine-independent manner. IPDef1 evoked itch by activating mouse MrgprC11 and human MRGPRX1 on dorsal root ganglion neurons. IPDef1-activated MrgprC11/X1 signaling sensitized downstream ion channel TRPV1 on dorsal root ganglion neurons. Moreover, IPDef1 also activated mouse MrgprB2 and its ortholog human MRGPRX2 selectively expressed on mast cells, inducing the release of inflammatory cytokines and driving acute inflammation in mice, although mast cell activation did not contribute to oxidated IPDef1-induced itch. CONCLUSIONS: Our study identifies tick salivary peptides as a new class of pruritogens that initiate itch through MrgprC11/X1-TRPV1 signaling in pruritoceptors. Our work will provide potential drug targets for the prevention and treatment of pruritus induced by the bites or stings of tick and maybe other arthropods.


Assuntos
Peptídeos/imunologia , Receptores Acoplados a Proteínas G/metabolismo , Canais de Cátion TRPV/metabolismo , Carrapatos/imunologia , Alérgenos/imunologia , Animais , Suscetibilidade a Doenças , Humanos , Camundongos , Prurido/imunologia , Prurido/metabolismo
14.
Bioorg Chem ; 106: 104199, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33317837

RESUMO

Hereby, we report our efforts on discovery and optimization of a new series of 5-aryl-4-(4-arylpiperazine-1-carbonyl)-1,2,3-thiadiazoles as new microtubule-destabilizing agents along our previous study. Guided by docking model analysis, we introduced the 1,2,3-thiadiazole moiety containing the hydrogen-bond acceptors as B-ring of XRP44X analogues. Extensive structure modifications were performed to investigate the detailed structure and activity relationships (SARs). Some compounds exhibited potent antiproliferative activities against three human cancer cell lines (SGC-7901, A549 and HeLa). The compound 5m exhibited the highest potency against the three cancer cell lines. The tubulin polymerization experiments indicated that compound 5m effectively inhibited the tubulin polymerization, and immunostaining assay revealed that it significantly disrupted microtubule dynamics. Moreover, cell cycle studies revealed that compound 5m dramatically arrested cell cycle progression at G2/M phase.


Assuntos
Antineoplásicos/farmacologia , Piperazinas/farmacologia , Tiadiazóis/farmacologia , Moduladores de Tubulina/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Desenho de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Humanos , Simulação de Acoplamento Molecular , Estrutura Molecular , Piperazinas/síntese química , Piperazinas/metabolismo , Polimerização/efeitos dos fármacos , Ligação Proteica , Relação Estrutura-Atividade , Tiadiazóis/síntese química , Tiadiazóis/metabolismo , Tubulina (Proteína)/efeitos dos fármacos , Tubulina (Proteína)/metabolismo , Moduladores de Tubulina/síntese química , Moduladores de Tubulina/metabolismo
15.
Bioorg Chem ; 104: 103909, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33142419

RESUMO

A series of novel 5-methyl-4-aryl-3-(4-arylpiperazine-1-carbonyl)-4H-1,2,4-triazoles possessing 1,2,4-triazole as the hydrogen-bond acceptor were designed, synthesized and evaluated for their antiproliferative and tubulin polymerization inhibitory activities. Some of them exhibited moderate activities in vitro against the three cancer cell lines including SGC-7901, A549 and HeLa. Compound 6e exhibited the highest potency against the three cancer cell lines. Moreover, the tubulin polymerization experiments indicated that compound 6e could inhibit the tubulin polymerization. Immunofluorescence study and cell cycle analysis clearly revealed compound 6e could disrupt intracellular microtubule organization, arrest cell cycle at the G2/M phase. In addition, molecular docking analysis demonstrated the interaction of compound 6e at the colchicine-binding site of tubulin. These preliminary results suggested that compound 6e is a new colchicine binding site inhibitor and worthy of further investigation.


Assuntos
Antineoplásicos/farmacologia , Desenho de Fármacos , Triazóis/farmacologia , Moduladores de Tubulina/farmacologia , Tubulina (Proteína)/metabolismo , Antineoplásicos/síntese química , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Modelos Moleculares , Estrutura Molecular , Relação Estrutura-Atividade , Triazóis/síntese química , Triazóis/química , Moduladores de Tubulina/síntese química , Moduladores de Tubulina/química , Células Tumorais Cultivadas
16.
Int Immunopharmacol ; 88: 106971, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33182029

RESUMO

Melanoma is a highly invasive malignant tumor, metastasis can occur in the early stage of the tumor, and the prognosis of patients in the late stage is extremely poor. Programmed cell death protein 1/programmed death-ligand 1 (PD-1/PD-L1) immune checkpoint inhibitors have made a major breakthrough in cancer treatment, which makes the treatment of melanoma enter a new period. The expression of PD-L1 in melanoma is an important biomarker to predict the inhibitory response to the immune checkpoint and is considered to be an independent prognostic indicator of melanoma. Although the related immune checkpoint inhibitors have achieved some good results, the regulation of PD-L1 expression in melanoma is complex and contains multiple types, and few detailed summaries have been done on all types of regulation, so it is very important to explore the complicated regulation mechanism of PD-L1 in melanoma. In this review, we systematically summarize the latest progress on the mechanism of PD-L1 expression regulation in melanoma. The regulatory factors positively related to PD-L1 include internal factors, external induction, signal pathway, transcription factors, epigenetics (Hypomethylation, HDAC6), translation and post-translation levels, while factors negatively related to PD-L1 include microRNA and epigenetics (HDAC8). In addition, the regulation of PD-L1 on the exosome surface is mediated by IFN-γ and there is a positive correlation between them. We hope this review will lay a foundation for the development of more effective and less toxic drugs for immunotherapy of melanoma.


Assuntos
Antineoplásicos/farmacologia , Antígeno B7-H1/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Melanoma/metabolismo , Antígeno B7-H1/genética , Sistemas de Liberação de Medicamentos , Humanos
17.
Theranostics ; 10(26): 12223-12240, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33204339

RESUMO

Rationale: Many viral infections are known to activate the p38 mitogen-activated protein kinase (MAPK) signaling pathway. However, the role of p38 activation in viral infection and the underlying mechanism remain unclear. The role of virus-hijacked p38 MAPK activation in viral infection was investigated in this study. Methods: The correlation of hepatitis C virus (HCV) infection and p38 activation was studied in patient tissues and primary human hepatocytes (PHHs) by immunohistochemistry and western blotting. Coimmunoprecipitation, GST pulldown and confocal microscopy were used to investigate the interaction of p38α and the HCV core protein. In vitro kinase assays and mass spectrometry were used to analyze the phosphorylation of the HCV core protein. Plaque assays, quantitative real time PCR (qRT-PCR), western blotting, siRNA and CRISPR/Cas9 were used to determine the effect of p38 activation on viral replication. Results: HCV infection was associated with p38 activation in clinical samples. HCV infection increased p38 phosphorylation by triggering the interaction of p38α and TGF-ß activated kinase 1 (MAP3K7) binding protein 1 (TAB1). TAB1-mediated p38α activation facilitated HCV replication, and pharmaceutical inhibition of p38α activation by SB203580 suppressed HCV infection at the viral assembly step. Activated p38α interacted with the N-terminal region of the HCV core protein and subsequently phosphorylated the HCV core protein, which promoted HCV core protein oligomerization, an essential step for viral assembly. As expected, SB203580 or the HCV core protein N-terminal peptide (CN-peptide) disrupted the p38α-HCV core protein interaction, efficiently impaired HCV assembly and impeded normal HCV replication in both cultured cells and primary human hepatocytes. Similarly, severe fever with thrombocytopenia syndrome virus (SFTSV), herpes simplex virus type 1 (HSV-1) or severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection also activated p38 MAPK. Most importantly, pharmacological blockage of p38 activation by SB203580 effectively inhibited SFTSV, HSV-1 and SARS-CoV-2. Conclusion: Our study shows that virus-hijacked p38 activation is a key event for viral replication and that pharmacological blockage of p38 activation is an antiviral strategy.


Assuntos
COVID-19/metabolismo , Hepacivirus/metabolismo , Hepatite C/metabolismo , Proteína Quinase 14 Ativada por Mitógeno/metabolismo , SARS-CoV-2/metabolismo , Glicoproteína da Espícula de Coronavírus/metabolismo , Células A549 , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , COVID-19/virologia , Chlorocebus aethiops , Ativação Enzimática , Células HEK293 , Hepatite C/patologia , Hepatite C/virologia , Hepatócitos/metabolismo , Humanos , Imidazóis/farmacologia , MAP Quinase Quinase Quinases/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Proteína Quinase 14 Ativada por Mitógeno/antagonistas & inibidores , Fosforilação , Piridinas/farmacologia , Células Vero , Proteínas do Core Viral/metabolismo , Replicação Viral/efeitos dos fármacos
18.
FASEB J ; 34(11): 15093-15107, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32918769

RESUMO

Clinical fungal infections always cause a negative impact on human health. Moreover, during the interaction of pathogenic fungi with the environment and host, many biologically active substances are produced. Here, we report a new toxin-like defensin of purlisin derived from a clinical pathogenic isolate of Purpureocillium lilacinum. The analysis of its genomic and mRNA sequences revealed an open reading frame of 444 bp without introns. The deduced precursor peptide was composed of 147 amino acids, and the mature peptide were identified at protein level by LC-ESI-Q-TOF-MS/MS. After posttranslational processing, the precursor peptide of purlisin was split into two independent peptides. The two mature defensins, purlisin-NT and purlisin-CT, are consisting of 36 and 38 amino acid residues, which can form three and four intramolecular disulfide bonds, respectively. The results of circular dichroism and homology modeling revealed that they adopted a representative cysteine-stabilized α-helical and ß-sheet motif. The purlisin-NT showed a dose-dependent selective inhibition of immune-related hKv1.3 target channel with IC50 value of 0.2 ± 0.04 µM but no obvious antibacterial activity, while the purlisin-CT displayed antimicrobial activities against gram-positive bacteria as well as clinical isolates of MRSA and low affinities for potassium channels. Our findings suggest that purlisin-NT with immunosuppressive effects and purlisin-CT possessing antibacterial activities are adapted to the survival and pathogenicity of clinical P lilacinumis. Moreover, they can also be used as templates for the design of novel antibacterial peptide and immunosuppressive agents.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Defensinas/farmacologia , Proteínas Fúngicas/metabolismo , Hypocreales/química , Fragmentos de Peptídeos/farmacologia , Bloqueadores dos Canais de Potássio/farmacologia , Sequência de Aminoácidos , Sequência de Bases , Proteínas Fúngicas/genética , Humanos , Canais de Potássio/química , Homologia de Sequência
19.
Biochem Biophys Res Commun ; 532(2): 265-270, 2020 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-32863001

RESUMO

Methotrexate (MTX) has been widely used for the treatment of many types of autoimmune diseases, such as rheumatoid arthritis, psoriasis and dermatomyositis. However, its pharmacological mechanism is still unclear completely. In this study, we found that MTX is a potent and selective inhibitor of the Kv1.3 channel, a class of potassium channels highly associated with autoimmune diseases. Electrophysiological experiments showed that MTX inhibited human Kv1.3 channel with an IC50 of 41.5 ± 24.9 nM, and 1 µM MTX inhibited 32.6 ± 1.3% and 25.6 ± 2.2% of human Kv1.1 and Kv1.2 channel currents, respectively. These data implied the unique selectivity of MTX towards the Kv1.3 channel. Excitingly, using channel activation and chimeric experiments, we found that MTX bound to the outer pore region of Kv1.3 channel. Mutagenesis experiments in the Kv.3 channel extracellular pore region further showed that the Dsp371, Thr373 and His399 residues of outer pore region of Kv1.3 channel played important roles in MTX inhibiting activities. In conclusion, MTX inhibited Kv1.3 channel by targeting extracellular pore region, which is different form all the report small molecules, such as PAP-1 and 4-AP, but similar with many natural animal toxin peptides, such as ChTX, ShK and BmKTX. To the best of our knowledge, MTX is the first small molecular scaffold targeting the Kv1.3 channel extracellular pore region, suggesting its potential applications for designing novel Kv1.3 lead drugs and treating Kv1.3 channel-associated autoimmune diseases.


Assuntos
Canal de Potássio Kv1.3/antagonistas & inibidores , Canal de Potássio Kv1.3/metabolismo , Metotrexato/química , Metotrexato/farmacologia , Bloqueadores dos Canais de Potássio/farmacologia , Sítios de Ligação , Relação Dose-Resposta a Droga , Canal de Potássio ERG1/antagonistas & inibidores , Canal de Potássio ERG1/metabolismo , Células HEK293 , Humanos , Canal de Potássio Kv1.3/genética , Metotrexato/administração & dosagem , Mutagênese , Técnicas de Patch-Clamp , Bloqueadores dos Canais de Potássio/administração & dosagem , Bloqueadores dos Canais de Potássio/química
20.
Toxicol In Vitro ; 69: 104971, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32805372

RESUMO

Lung cancer is the most common cause of cancer-related death worldwide. The occurrence of multidrug resistance (MDR) affects the therapeutic efficacy of chemotherapeutics. Therefore, to develop new anticarcinogen which can overcome MDR is urgent. Here, the novel microtubule inhibitor 5-(4-ethoxyphenyl)-1-(3,4,5-trimethoxyphenyl)-1H-1,2,4-triazol-3-amine (YAN) exhibited strong cytotoxicity towards A549 and MDR-phenotype A549/Taxol cells. We demonstrated that YAN was a poor substrate of P-glycoprotein (P-gp) and multidrug resistance-associated protein 1 (MRP1) which were over-expressed in A549/Taxol cells, and YAN inhibited their expression and function. Moreover, YAN arrested cells at mitosis phase by inhibiting microtubule polymerization. Further, YAN induced caspase-dependent apoptosis in A549 cells via mitochondria-mediated intrinsic pathway. In contrast, the multinucleation of A549/Taxol cells after YAN-treatment indicated the occurrence of mitotic catastrophe, and the subsequent apoptosis was mediated by apoptosis-inducing factor (AIF) nuclear translocation instead of p53- and caspase-dependent manner. Moreover, the inhibitory effect of YAN on PI3K/Akt activity was involved in the regulation of P-gp, MRP1 and AIF in A549/Taxol cells. Taken together, our finding indicates that YAN is a novel microtubule inhibitor and overcomes MDR by suppressing P-gp and MRP1 function and inducing cell death independent of p53 and caspase in A549/Taxol cells. Therefore, YAN possesses great potential for future development into an effective anticarcinogen especially for drug-resistant cancer.


Assuntos
Antineoplásicos/farmacologia , Moduladores de Tubulina/farmacologia , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Humanos , Camundongos , Mitose/efeitos dos fármacos , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Paclitaxel/farmacologia
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