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1.
Chem Biol Interact ; 308: 101-109, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31100281

RESUMO

Eight derivatives of 4-aminoquinolines differing in the substituents attached to the C(4)-amino group and C(7) were synthesised and tested as inhibitors of human acetylcholinesterase (AChE) and butyrylcholinesterase (BChE). Both enzymes were inhibited by all of the compounds with inhibition constants (Ki) ranging from 0.50 to 50 µM exhibiting slight selectivity toward AChE over BChE. The most potent inhibitors of AChE were compounds with an n-octylamino chain or adamantyl group. The shortening of the chain length resulted in a decrease in AChE inhibition by 5-20 times. Docking studies revealed that the quinoline group within the AChE active site was positioned in the choline binding site, while the C(4)-amino group substituents, depending on their lipophilicity, could establish hydrogen bonds or π-interactions with residues of the peripheral anionic site. The most potent inhibitors of BChE were compounds with the most voluminous substituent on C(4)-amino group (adamantyl) or those with a stronger electron withdrawing substituent on C(7) (trifluormethyl group). Based on AChE inhibition, compounds with an n-octylamino chain or adamantyl substituent were shown to possess the capacity for further development as potential drugs for treatment of neurodegenerative diseases.


Assuntos
Acetilcolinesterase/química , Aminoquinolinas/química , Butirilcolinesterase/química , Inibidores da Colinesterase/química , Acetilcolinesterase/genética , Acetilcolinesterase/metabolismo , Aminoquinolinas/metabolismo , Sítios de Ligação , Barreira Hematoencefálica/metabolismo , Butirilcolinesterase/genética , Butirilcolinesterase/metabolismo , Domínio Catalítico , Inibidores da Colinesterase/metabolismo , Humanos , Cinética , Simulação de Acoplamento Molecular , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/isolamento & purificação
2.
Benef Microbes ; 10(4): 449-461, 2019 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-30957533

RESUMO

Anti-genotoxic or anti-mutagenic activity has been described for a number of Gram-positive probiotic bacterial species. Here we present evidence that Gram-negative Escherichia coli Nissle 1917 (EcN) also displays anti-genotoxic/anti-mutagenic activity, as assessed in vitro by the Comet Assay and the Ames Test, respectively. This activity was demonstrated by use of the mutagens 4-nitroquinoline-1-oxide (NQO), hydrogen peroxide (H2O2) and benzo(a) pyrene (B[a]P). For both assays and all three test agents the anti-genotoxic/anti-mutagenic activity of EcN was shown to be concentration dependent. By the use of extracts of bacteria that were inactivated by various procedures (heat treatment, ultrasound sonication or ultraviolet light irradiation), mechanistic explanations could be put forward. The proposed mechanisms were enforced by treating the bacterial material with proteinase K prior to testing. The mutagen H2O2 is most likely inactivated by enzymic activity, with catalase a likely candidate, while several explanations can be put forward for inactivation of B[a]P. NQO is most likely inactivated by metabolising enzymes, since the formation of the metabolite 4-aminoquinoline could be demonstrated. In conclusion, the in vitro results presented here make a strong case for antimutagenic properties of EcN.


Assuntos
Antimutagênicos/metabolismo , Escherichia coli/metabolismo , Mutagênicos/metabolismo , 4-Nitroquinolina-1-Óxido/metabolismo , 4-Nitroquinolina-1-Óxido/farmacologia , Aminoquinolinas/metabolismo , Benzo(a)pireno/metabolismo , Benzo(a)pireno/farmacologia , Células CACO-2 , Meios de Cultivo Condicionados , Endopeptidase K/farmacologia , Escherichia coli/efeitos dos fármacos , Humanos , Peróxido de Hidrogênio/metabolismo , Peróxido de Hidrogênio/farmacologia , Testes de Mutagenicidade , Mutagênicos/farmacologia
3.
Biochemistry ; 58(4): 245-249, 2019 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-30350580

RESUMO

Numerous studies have been published stressing the importance of finding ligands that can bind specifically to DNA secondary structures. Several have identified ligands that are presented as having specific binding to the G-quadruplex; however, these were not originally tested on the complementary i-motif structure. The i-motif was overlooked and presumed to be irrelevant due to the belief that the hemiprotonated (cytosine+-cytosine) base pair at the core of the structure required acidic pH. The pathophysiological relevance of i-motifs has since been documented, as well as the discovery of several genomic sequences, which can form i-motif at neutral pH. Using different biophysical methodologies, we provide experimental evidence to show that widely used G-quadruplex ligands interact with i-motif structures at neutral pH, generally leading to their destabilization. Crucially, this has implications both for the search for quadruplex binding compounds as well as for the effects of compounds reported to have G-quadruplex specificity without examining their effects on i-motif.


Assuntos
Quadruplex G , Motivos de Nucleotídeos , Acridinas/química , Acridinas/metabolismo , Aminoquinolinas/química , Aminoquinolinas/metabolismo , Proteínas Reguladoras de Apoptose/genética , Berberina/química , Berberina/metabolismo , Dicroísmo Circular , Concentração de Íons de Hidrogênio , Ligantes , Mitoxantrona/química , Mitoxantrona/metabolismo , Proteínas do Tecido Nervoso/genética , Ácidos Picolínicos/química , Ácidos Picolínicos/metabolismo , Porfirinas/química , Porfirinas/metabolismo , Temperatura de Transição
4.
Acta Pharmacol Sin ; 40(7): 980-988, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30382184

RESUMO

Pyrotinib is a novel irreversible EGFR/HER2 dual tyrosine kinase inhibitor that is used to treat HER2-positive breast cancer. In this study we investigated the metabolism and disposition of pyrotinib in six healthy Chinese men after a single oral dose of 402 mg of [14C]pyrotinib. At 240 h postdose, the mean cumulative excretion of the dose radioactivity was 92.6%, including 1.7% in urine and 90.9% in feces. In feces, oxidative metabolites were detected as major drug-related materials and the primary metabolic pathways were O-depicoline (M1), oxidation of pyrrolidine (M5), and oxidation of pyridine (M6-1, M6-2, M6-3, and M6-4). In plasma, the major circulating entities identified were pyrotinib, SHR150980 (M1), SHR151468 (M2), and SHR151136 (M5), accounting for 10.9%, 1.9%, 1.0%, and 3.0%, respectively, of the total plasma radioactivity based on the AUC0-∞ ratios. Approximately 58.3% of the total plasma radioactivity AUC0-∞ was attributed to covalently bound materials. After incubation of human plasma with [14C]pyrotinib at 37 °C for 2, 5, 8, and 24 h, the recovery of radioactivity by extraction was 97.4%, 91.8%, 69.6%, and 46.7%, respectively, revealing covalent binding occurred independently of enzymes. A group of pyrotinib adducts, including pyrotinib-lysine and pyrotinib adducts of the peptides Gly-Lys, Lys-Ala, Gly-Lys-Ala, and Lys-Ala-Ser, was identified after HCl hydrolysis of the incubated plasma. Therefore, the amino acid residue Lys190 of human serum albumin was proposed to covalently bind to pyrotinib via Michael addition. Finally, the covalently bound pyrotinib could dissociate from the human plasma protein and be metabolized by oxidation and excreted via feces.


Assuntos
Acrilamidas/metabolismo , Aminoquinolinas/metabolismo , Antineoplásicos/metabolismo , Inibidores de Proteínas Quinases/metabolismo , Albumina Sérica Humana/metabolismo , Acrilamidas/química , Acrilamidas/farmacocinética , Adulto , Aminoquinolinas/química , Aminoquinolinas/farmacocinética , Antineoplásicos/química , Antineoplásicos/farmacocinética , Análise Química do Sangue , Radioisótopos de Carbono , Fezes/química , Humanos , Masculino , Orosomucoide/metabolismo , Ligação Proteica , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacocinética , Albumina Sérica Humana/química , Urina/química
5.
Cell Chem Biol ; 26(2): 213-222.e6, 2019 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-30527998

RESUMO

Diabetes is a hyperglycemic condition characterized by pancreatic ß-cell dysfunction and depletion. Whereas methods for monitoring ß-cell function in vivo exist, methods to deliver therapeutics to ß cells are lacking. We leveraged the rare ability of ß cells to concentrate zinc to preferentially trap zinc-binding molecules within ß cells, resulting in ß-cell-targeted compound delivery. We determined that zinc-rich ß cells and islets preferentially accumulated TSQ (6-methoxy-8-p-toluenesulfonamido-quinoline) in a zinc-dependent manner compared with exocrine pancreas. Next, we asked whether appending a zinc-chelating moiety onto a ß-cell replication-inducing compound was sufficient to confer preferential ß-cell accumulation and activity. Indeed, the hybrid compound preferentially accumulated within rodent and human islets in a zinc-dependent manner and increased the selectivity of replication-promoting activity toward ß cells. These data resolve the fundamental question of whether intracellular accumulation of zinc-chelating compounds is influenced by zinc content. Furthermore, application of this principle yielded a proof-of-concept method for ß-cell-targeted drug delivery and bioactivity.


Assuntos
Quelantes/química , Células Secretoras de Insulina/metabolismo , Zinco/química , Aminoquinolinas/análise , Aminoquinolinas/química , Aminoquinolinas/metabolismo , Animais , Quelantes/metabolismo , Cromatografia Líquida de Alta Pressão , Ditizona/química , Ditizona/metabolismo , Etilenodiaminas/análise , Etilenodiaminas/química , Etilenodiaminas/metabolismo , Humanos , Células Secretoras de Insulina/citologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/metabolismo , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Tirosina Quinases/antagonistas & inibidores , Proteínas Tirosina Quinases/metabolismo , Espectrometria de Massas em Tandem , Compostos de Tosil/análise , Compostos de Tosil/química , Compostos de Tosil/metabolismo
6.
Chem Biol Drug Des ; 93(4): 638-646, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30570823

RESUMO

Traditional antimalarial drugs based on 4-aminoquinolines have exhibited good antiproliferative activities against human tumor cells; however, their low relative efficacy has limited their corresponding clinical uses. In order to identify new potent anticancer agents based on 4-aminoquinoline, we evaluated the antiproliferative activity of a series of dehydroxy isoquines and isotebuquines against five human cancer lines. HeLa and SKBr3 were significantly more sensitive to the action of tested quinolines than the A549, MCF-7, and PC-3 cancer lines. Compound 2h was by far the most potent derivative against four of the tested lines (except to PC3 line), exhibiting low micromolar or nanomolar IC50 values superior to adriamycin reference, low toxicities on dermis human fibroblasts (LD50  > 250 µM), and excellent selectivity indexes against the mentioned cancer cells. A structure-activity relationship analysis put in evidence that a pyrrolidine or morpholine moiety as N-alkyl terminal substitution and the incorporation of the extra phenyl attached to aniline ring are pharmacophore essentials for improvement the anticancer activity of the studied dehydroxy isoquines and isotebuquines. From the results, compound 2h emerged as a promising anticancer candidate for further in vitro assays against resistant-strain and in vivo studies as well as pharmacokinetic and genotoxicity studies. Mechanistic assays suggested that the most active quinoline 2h act as calcium-activated potassium channel activator.


Assuntos
Aminoquinolinas/química , Antineoplásicos/química , Canais de Potássio/química , Potenciais de Ação/efeitos dos fármacos , Aminoquinolinas/metabolismo , Aminoquinolinas/farmacologia , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Desenho de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Canais de Potássio/metabolismo , Relação Estrutura-Atividade
7.
Sci Rep ; 8(1): 14029, 2018 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-30232344

RESUMO

EP0 is an important early gene that modulates the life cycle of pseudorabies virus (PRV). A guanine-rich sequence overlapping with three Sp1 binding sites is located upstream of the transcription start site (TSS) in the EP0 promoter. Using native polyacrylamide gel electrophoresis (PAGE) and circular dichroism (CD), we verified that the G-rich region in the EP0 promoter forms an intramolecular parallel G-quadruplex (G4) in the presence of K+ ions. Further dimethyl sulphate (DMS) footprinting and Taq polymerase stop assays indicates the potential polymorphic folding of G4. In addition, a small chemical ligand, pyridostatin (PDS), promotes and stabilizes the formation of G4. Interestingly, based on the results of electrophoretic mobility shift assays (EMSA), the Sp1 protein bound to G4-bearing DNA with more affinity than DNA lacking the G4 structure. According to the luciferase reporter assay, G4 negatively regulates the EP0 promoter activity. These results demonstrate that Sp1 and G4 cooperate to regulate EP0 promoter activity.


Assuntos
Herpesvirus Suídeo 1/genética , Regiões Promotoras Genéticas , Proteínas Virais/metabolismo , Aminoquinolinas/metabolismo , Sítios de Ligação , Dicroísmo Circular , Conformação de Ácido Nucleico , Ácidos Picolínicos/metabolismo , Potássio/metabolismo , Proteínas Virais/química , Proteínas Virais/genética
8.
J Med Chem ; 61(15): 6546-6573, 2018 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-29890830

RESUMO

Epigenetic regulators that exhibit aberrant enzymatic activities or expression profiles are potential therapeutic targets for cancers. Specifically, enzymes responsible for methylation at histone-3 lysine-9 (like G9a) and aberrant DNA hypermethylation (DNMTs) have been implicated in a number of cancers. Recently, molecules bearing a 4-aminoquinoline scaffold were reported as dual inhibitors of these targets and showed a significant in vivo efficacy in animal models of hematological malignancies. Here, we report a detailed exploration around three growing vectors born by this chemotype. Exploring this chemical space led to the identification of features to navigate G9a and DNMT1 biological spaces: not only their corresponding exclusive areas, selective compounds, but also common spaces. Thus, we identified from selective G9a and first-in-class DNMT1 inhibitors, >1 log unit between their IC50 values, with IC50 < 25 nM (e.g., 43 and 26, respectively) to equipotent inhibitors with IC50 < 50 nM for both targets (e.g., 13). Their ADME/Tox profiling and antiproliferative efficacies, versus some cancer cell lines, are also reported.


Assuntos
Aminoquinolinas/química , Aminoquinolinas/farmacologia , Metilases de Modificação do DNA/antagonistas & inibidores , Desenho de Fármacos , Histona-Lisina N-Metiltransferase/antagonistas & inibidores , Aminoquinolinas/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Metilases de Modificação do DNA/química , Metilases de Modificação do DNA/metabolismo , Antígenos de Histocompatibilidade/química , Antígenos de Histocompatibilidade/metabolismo , Histona-Lisina N-Metiltransferase/química , Histona-Lisina N-Metiltransferase/metabolismo , Humanos , Concentração Inibidora 50 , Simulação de Acoplamento Molecular , Conformação Proteica
9.
Eur J Med Chem ; 149: 69-78, 2018 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-29499488

RESUMO

Hybrid compounds may play a critical role in the context of the malaria eradication agenda, which will benefit from therapeutic tools active against the symptomatic erythrocytic stage of Plasmodium infection, and also capable of eliminating liver stage parasites. To address the need for efficient multistage antiplasmodial compounds, a small library of 1,2,4,5-tetraoxane-8- aminoquinoline hybrids, with the metabolically labile C-5 position of the 8-aminoquinoline moiety blocked with aryl groups, was synthesized and screened for antiplasmodial activity and metabolic stability. The hybrid compounds inhibited development of intra-erythrocytic forms of the multidrug-resistant Plasmodium falciparum W2 strain, with EC50 values in the nM range, and with low cytotoxicity against mammalian cells. The compounds also inhibited the development of P. berghei liver stage parasites, with the most potent compounds displaying EC50 values in the low µM range. SAR analysis revealed that unbranched linkers between the endoperoxide and 8-aminoquinoline pharmacophores are most beneficial for dual antiplasmodial activity. Importantly, hybrids were significantly more potent than a 1:1 mixture of 8-aminoquinoline-tetraoxane, highlighting the superiority of the hybrid approach over the combination therapy. Furthermore, aryl substituents at C-5 of the 8-aminoquinoline moiety improve the compounds' metabolic stability when compared with their primaquine (i.e. C-5 unsubstituted) counterparts. Overall, this study reveals that blocking the quinoline C-5 position does not result in loss of dual-stage antimalarial activity, and that tetraoxane-8- aminoquinoline hybrids are an attractive approach to achieve elimination of exo- and intraerythrocytic parasites, thus with the potential to be used in malaria eradication campaigns.


Assuntos
Aminoquinolinas/química , Aminoquinolinas/uso terapêutico , Antimaláricos/síntese química , Aminoquinolinas/metabolismo , Animais , Antimaláricos/metabolismo , Antimaláricos/farmacologia , Avaliação Pré-Clínica de Medicamentos , Estabilidade de Medicamentos , Eritrócitos/parasitologia , Humanos , Fígado/parasitologia , Peróxidos/química , Peróxidos/metabolismo , Plasmodium berghei/efeitos dos fármacos , Plasmodium falciparum/efeitos dos fármacos , Bibliotecas de Moléculas Pequenas/síntese química , Relação Estrutura-Atividade
10.
Int Immunopharmacol ; 56: 339-348, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29454234

RESUMO

BACKGROUND AND OBJECT: Dendritic cells (DCs) are critical for initiating the activation and differentiation of T cells in inflammatory diseases including psoriasis. Curcuma kwangsiensis S.G. Lee & C.F. Liang is a herb for treating psoriasis and we previously found Diarylheptanoid from rhizomes of Curcuma kwangsiensis (DCK) inhibited keratinocytes proliferation. However, it is unknown whether DCK influences DC functions. Thus we aimed to explore whether DCK affect the major immunological functions of DCs. MATERIALS AND METHODS: Primary DCs derived from mouse bone marrow cells and spleen were used for examining their general immunological functions, and OVA-specific T cells from OT-II mice were used for examining the DC-mediated T-helper (Th) 1 and Th17 cells differentiation and effect. RESULTS: We demonstrated DCK suppressed DC uptake of FITC-labeled ovalbumin (OVA) and DC maturation characterized by decreased MHCII, CD80 and CD86 following imiquimod (IMQ) stimulation. DCK also reduced DC expression of the lymphoid-homing chemokine receptor CCR7, and DC migration towards CCL21, the ligand for CCR7. Importantly, DCK significantly reduced the production of proinflammatory cytokines including IL-12, IL-6 and IL-1ß by IMQ-stimulated DCs. Moreover, in the coculture of OVA323-339 peptide-pulsed DCs and OVA-specific T cells from OT-II mice, DCK significantly inhibited T cell proliferation and the differentiation of Th1 and Th17 cells. Furthermore, DCK treatment greatly reduced phosphorylation of p65-associated cell signaling pathway in IMQ-stimulated DCs. CONCLUSION: These data together demonstrate a potential role of DCK in suppressing the biological function of DCs, and provide a possible mechanism for understanding the effects of herb Curcuma kwangsiensis in treating psoriasis.


Assuntos
Anti-Inflamatórios/farmacologia , Células Dendríticas/imunologia , Diarileptanoides/farmacologia , Células Th1/imunologia , Células Th17/imunologia , Aminoquinolinas/metabolismo , Animais , Diferenciação Celular , Células Cultivadas , Curcuma/imunologia , Imiquimode , Ativação Linfocitária , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Rizoma
11.
Biomed Chromatogr ; 32(6): e4207, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29430676

RESUMO

Naphthoquine (NQ) is one of important partner drugs of artemisinin-based combination therapy (ACT), which is recommended for the treatment of uncomplicated Plasmodium falciparum. NQ shows a high cure rate after a single oral administration. It is absorbed quickly (time to peak concentration 2-4 h) and has a long elimination half-life (255 h). However, the metabolism of NQ has not been clarified. In this work, the metabolite profiling of NQ was studied in six liver microsomal incubates (human, cynomolgus monkey, beagle dog, mini pig, rat and CD1 mouse), seven recombinant CYP enzymes (1A2, 2B6, 2C8, 2C9, 2C19, 2D6 and 3A4) and rat (plasma, urine, bile and feces) using liquid chromatography tandem high-resolution LTQ-Orbitrap mass spectrometry (HRMSn ) in conjunction with online hydrogen/deuterium exchange. The biological samples were pretreated by protein precipitation and solid-phase extraction. For data processing, multiple data-mining tools were applied in tandem, i.e. background subtraction and followed by mass defect filter. NQ metabolites were characterized by accurate MS/MS fragmentation characteristics, the hydrogen/deuterium exchange data and cLogP simulation. As a result, five phase I metabolites (M1-M5) of NQ were characterized for the first time. Two metabolic pathways were involved: hydroxylation and N-oxidation. This study demonstrates that LC-HRMSn in combination with multiple data-mining tools in tandem can be a valuable analytical strategy for rapid metabolite profiling of drugs.


Assuntos
1-Naftilamina/análogos & derivados , Aminoquinolinas/metabolismo , Antimaláricos/metabolismo , Cromatografia Líquida/métodos , Espectrometria de Massas em Tandem/métodos , 1-Naftilamina/análise , 1-Naftilamina/metabolismo , Aminoquinolinas/análise , Animais , Antimaláricos/análise , Biologia Computacional , Mineração de Dados , Medição da Troca de Deutério , Feminino , Masculino , Ratos Wistar
12.
J Low Genit Tract Dis ; 22(1): 52-57, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29271858

RESUMO

OBJECTIVES: Localized provoked vulvodynia (LPV) afflicts approximately 8% of women in the United States and represents a huge financial, physical, and psychological burden. Women with LPV experience intense pain localized to the vulvar vestibule (area immediately surrounding vaginal opening). We have identified mechanisms involved in the development of LPV whereby vulvar fibroblasts respond to proinflammatory stimuli to perpetuate an inflammatory response that causes pain. However, these mechanisms are not fully elucidated. Therefore, we explored the role of toll-like receptors (TLRs), a class of innate immune receptors that rapidly respond to microbial assaults. MATERIALS AND METHODS: To determine whether TLRs are expressed by vulvar fibroblasts and whether these contribute to proinflammatory mediator production and pain in LPV, we examined TLR expression and innate immune responses in fibroblasts derived from painful vestibular regions compared with nonpainful external vulvar regions. RESULTS: Human vulvar fibroblasts express functional TLRs that trigger production of inflammatory mediators associated with chronic pain. We focused on the TLR-7-imiquimod proinflammatory interaction, because imiquimod, a ligand of TLR-7, may exacerbate pain in women during treatment of human papillomavirus-associated disease. CONCLUSIONS: Human vulvar fibroblasts express a broad spectrum of TLRs (a new finding). A significantly higher TLR-mediated proinflammatory response was observed in LPV case vestibular fibroblasts, and with respect to the imiquimod-TLR 7 interaction, development of chronic vestibular pain and inflammation may be a possible sequelae of treatment of vulvar human papillomavirus-associated disease. Suppressing enhanced TLR-associated innate immune responses to a spectrum of pathogen-associated molecular patterns may represent a new/effective therapeutic approach for vulvodynia.


Assuntos
Aminoquinolinas/metabolismo , Fibroblastos/imunologia , Imunidade Inata , Mediadores da Inflamação/metabolismo , Transdução de Sinais , Receptor 7 Toll-Like/análise , Vulvodinia/induzido quimicamente , Células Cultivadas , Feminino , Fibroblastos/metabolismo , Perfilação da Expressão Gênica , Humanos , Imiquimode , Receptor 7 Toll-Like/genética , Vulvodinia/patologia
13.
Sci Rep ; 7(1): 17444, 2017 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-29234104

RESUMO

Hepatocyte nuclear factor 4-alpha (HNF4α) is a well established master regulator of liver development and function. We identified the in vitro presence of a stable secondary structure, G-quadruplex (G4) in the 5' UTR of P1-HNF4A, the predominant HNF4α isoform(s) in adult liver. Our data suggest that the cooperation of G4 and the adjacent putative protein-binding sites within the 5' UTR was necessary and sufficient to mediate a strong translational repression. This was supported by analysis of deleted/mutated 5'UTRs and two native regulatory single-nucleotide polymorphisms in the 5'UTR. Additional results indicated that G4 motifs in the 5' UTRs of other liver-enriched transcription factors also inhibited protein expression. Moreover, pyridostatin, a G4 ligand, specifically potentiated the translational suppressing effect of P1-HNF4A-5' UTR. In summary, the present study provides the first evidence of the presence of G4 in human P1-HNF4A-5' UTR in vitro, and establishes a novel working model of strong inhibition of protein translation via interactions of G4 with potential RNA-binding proteins (RBPs). The protein expression of the tumor suppressor HNF4α may be inhibited by interactions of RBPs with the G4 motif in the 5' UTR to promote cell proliferation during liver development and carcinogenesis.


Assuntos
Regiões 5' não Traduzidas , Quadruplex G , Fator 4 Nuclear de Hepatócito/genética , Fator 4 Nuclear de Hepatócito/metabolismo , Biossíntese de Proteínas/fisiologia , Aminoquinolinas/metabolismo , Sítios de Ligação , Regulação Leucêmica da Expressão Gênica , Células HEK293 , Células Hep G2 , Humanos , Mutação , Ácidos Picolínicos/metabolismo , Polimorfismo de Nucleotídeo Único , Biossíntese de Proteínas/genética
14.
Biochim Biophys Acta Gen Subj ; 1861(5 Pt B): 1353-1361, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28087374

RESUMO

G-quadruplexes (G4s) have become important drug targets to regulate gene expression and telomere maintenance. Many studies on G4 ligand binding focus on determining the ligand binding affinities and selectivities. Ligands, however, can also affect the G4 conformation. Here we explain how to use electrospray ionization mass spectrometry (ESI-MS) to monitor simultaneously ligand binding and cation binding stoichiometries. The changes in potassium binding stoichiometry upon ligand binding hint at ligand-induced conformational changes involving a modification of the number of G-quartets. We investigated the interaction of three quadruplex ligands (PhenDC3, 360A and Pyridostatin) with a variety of G4s. Electrospray mass spectrometry makes it easy to detect K+ displacement (interpreted as quartet disruption) upon ligand binding, and to determine how many ligand molecules must be bound for the quartet opening to occur. The reasons for ligand-induced conversion to antiparallel structures with fewer quartets are discussed. Conversely, K+ intake (hence quartet formation) was detected upon ligand binding to G-rich sequences that did not form quadruplexes in 1mM K+ alone. This demonstrates the value of mass spectrometry for assessing not only ligand binding, but also ligand-induced rearrangements in the target sequence. This article is part of a Special Issue entitled "G-quadruplex" Guest Editor: Dr. Concetta Giancola and Dr. Daniela Montesarchio.


Assuntos
Aminoquinolinas/metabolismo , Quadruplex G , Guanosina/metabolismo , Oligonucleotídeos/metabolismo , Ácidos Picolínicos/metabolismo , Piridinas/metabolismo , Quinolinas/metabolismo , Espectrometria de Massas por Ionização por Electrospray , Aminoquinolinas/química , Sítios de Ligação , Dicroísmo Circular , Guanosina/química , Ligantes , Modelos Moleculares , Oligonucleotídeos/química , Ácidos Picolínicos/química , Potássio/química , Potássio/metabolismo , Piridinas/química , Quinolinas/química , Relação Estrutura-Atividade
15.
Mol Ther ; 24(12): 2078-2089, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27731313

RESUMO

Phosphodiesterase 4 (PDE4) inhibitors are approved for the treatment of some moderate to severe inflammatory conditions. However, dose-limiting side effects in the central nervous system and gastrointestinal tract, including nausea, emesis, headache, and diarrhea, have impeded the broader therapeutic application of PDE4 inhibitors. We sought to exploit the wealth of validation surrounding PDE4 inhibition by improving the therapeutic index through generation of an antibody-drug conjugate (ADC) that selectively targets immune cells through the CD11a antigen. The resulting ADC consisted of a human αCD11a antibody (based on efalizumab clone hu1124) conjugated to an analog of the highly potent PDE4 inhibitor GSK256066. Both the human αCD11a ADC and a mouse surrogate αCD11a ADC (based on the M17 clone) rapidly internalized into immune cells and suppressed lipololysaccharide (LPS)-induced TNFα secretion in primary human monocytes and mouse peritoneal cells, respectively. In a carrageenan-induced air pouch inflammation mouse model, treatment with the ADC significantly reduced inflammatory cytokine production in the air pouch exudate. Overall, these results provide compelling evidence for the feasibility of delivering drugs with anti-inflammatory activity selectively to the immune compartment via CD11a and the development of tissue-targeted PDE4 inhibitors as a promising therapeutic modality for treating inflammatory diseases.


Assuntos
Aminoquinolinas/metabolismo , Antígenos CD11/metabolismo , Imunoconjugados/administração & dosagem , Inflamação/imunologia , Inibidores da Fosfodiesterase 4/metabolismo , Sulfonas/metabolismo , Animais , Células Cultivadas , Modelos Animais de Doenças , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Imunoconjugados/farmacologia , Lipopolissacarídeos/efeitos adversos , Camundongos , Monócitos/efeitos dos fármacos , Monócitos/imunologia , Peritônio/efeitos dos fármacos , Peritônio/imunologia , Fator de Necrose Tumoral alfa/metabolismo
16.
J Chromatogr B Analyt Technol Biomed Life Sci ; 1033-1034: 117-127, 2016 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-27541626

RESUMO

Pyrotinib is a novel irreversible tyrosine kinase inhibitor developed for the treatment of human epidermal growth factor receptor 2 (HER2)-positive breast cancer. The results of phase I clinical trial demonstrated that pyrotinib was well tolerated and exhibited potent antitumor activity. As a promising therapeutic agent for HER2-positive breast cancer, it is of great importance to investigate the biotransformation of pyrotinib in humans and identify the major enzymes involved in its metabolism during its early stage of development for safety consideration. For this purpose, a robust analytical method based on ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry (UPLC/Q-TOF MS) was established to characterize the metabolites of pyrotinib in human plasma, feces, and urine, and identify the primary enzymes responsible for its metabolism. As a result, a total of 24 metabolites were identified, including 16 phase I metabolites resulting from dealkylation, oxidation, dehydrogenation, and carbonylation, and 8 phase II metabolites originating from cysteine and N-acetylcysteine conjugation. Pyrotinib was absorbed into blood by 1h, reached its peak level at 4h, and afterwards underwent slow elimination. The principal metabolites detected in humans (M1, M2, and M5) were products resulting from O-depicoline and pyrrolidine lactam formation, whose structures have been confirmed by the synthetic references. In addition, fecal clearance was the major route of excretion for pyrotinib. Further phenotyping experiment proved that CYP3A4 was the most active enzyme responsible for the biotransformation of pyrotinib, implying the vital necessity of the assessment of the potential CYP3A-mediated drug-drug interactions in humans. Taken together, this study provided valuable metabolic data to explicate the dynamic process of pyrotinib in humans, and important reference basis for its safety evaluation and rational clinical application. The results will also benefit the assessment of the contributions to the overall activity or toxicity from the key metabolites.


Assuntos
Acrilamidas/sangue , Acrilamidas/metabolismo , Aminoquinolinas/sangue , Aminoquinolinas/metabolismo , Antineoplásicos/sangue , Antineoplásicos/metabolismo , Cromatografia Líquida de Alta Pressão/métodos , Inibidores de Proteínas Quinases/sangue , Inibidores de Proteínas Quinases/metabolismo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Acrilamidas/química , Acrilamidas/farmacocinética , Aminoquinolinas/química , Aminoquinolinas/farmacocinética , Antineoplásicos/química , Antineoplásicos/farmacocinética , Humanos , Redes e Vias Metabólicas , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacocinética
17.
Toxins (Basel) ; 8(8)2016 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-27517960

RESUMO

C2-toxin from Clostridium botulinum and Iota-toxin from Clostridium perfringens belong both to the binary A-B-type of toxins consisting of two separately secreted components, an enzymatic subunit A and a binding component B that facilitates the entry of the corresponding enzymatic subunit into the target cells. The enzymatic subunits are in both cases actin ADP-ribosyltransferases that modify R177 of globular actin finally leading to cell death. Following their binding to host cells' receptors and internalization, the two binding components form heptameric channels in endosomal membranes which mediate the translocation of the enzymatic components Iota a and C2I from endosomes into the cytosol of the target cells. The binding components form ion-permeable channels in artificial and biological membranes. Chloroquine and related 4-aminoquinolines were able to block channel formation in vitro and intoxication of living cells. In this study, we extended our previous work to the use of different chloroquine analogs and demonstrate that positively charged aminoquinolinium salts are able to block channels formed in lipid bilayer membranes by the binding components of C2- and Iota-toxin. Similarly, these molecules protect cultured mammalian cells from intoxication with C2- and Iota-toxin. The aminoquinolinium salts did presumably not interfere with actin ADP-ribosylation or receptor binding but blocked the pores formed by C2IIa and Iota b in living cells and in vitro. The blocking efficiency of pores formed by Iota b and C2IIa by the chloroquine analogs showed interesting differences indicating structural variations between the types of protein-conducting nanochannels formed by Iota b and C2IIa.


Assuntos
ADP Ribose Transferases/antagonistas & inibidores , Aminoquinolinas/farmacologia , Toxinas Bacterianas/antagonistas & inibidores , Toxinas Botulínicas/antagonistas & inibidores , Membrana Celular/efeitos dos fármacos , Cloroquina/farmacologia , ADP Ribose Transferases/metabolismo , Aminoquinolinas/química , Aminoquinolinas/metabolismo , Animais , Toxinas Bacterianas/metabolismo , Sítios de Ligação , Transporte Biológico , Toxinas Botulínicas/metabolismo , Membrana Celular/metabolismo , Cloroquina/análogos & derivados , Cloroquina/química , Cloroquina/metabolismo , Bicamadas Lipídicas , Camundongos , Estrutura Molecular , Ligação Proteica , Relação Estrutura-Atividade , Células Vero
18.
Int J Pharm ; 511(1): 516-523, 2016 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-27452419

RESUMO

Imiquimod (IMQ) ia an immunostimulating drug used for the treatment of neoplastic skin diseases, such as actinic keratosis (AK) and superficial basal cell carcinoma (sBCC), and as adjuvant for vaccination. Imiquimod formulation and skin delivery is highly challenging because of its very low solubility in most pharmaceutical excipients and poor penetration properties. Objectives of the work were: (1) to evaluate IMQ solubility in different solvents and pharmaceutical excipients; (2) to evaluate IMQ skin retention after the application of simple saturated solutions; (3) to evaluate the role of stratum corneum and solvent uptake on IMQ skin retention and (4) to formulate IMQ in microemulsions - prepared using previously investigated components - and compare them with the commercial formulation. The results show that IMQ solubility is not related to the solubility parameter of the solvents considered. The highest solubility was found with oleic acid (74mg/ml); in the case of PEGs, the solubility increased linearly with MW (PEG 200: 1.9mg/ml; PEG 400 7.3mg/ml, PEG 600 12.8mg/ml). Imiquimod skin retention from saturated solutions (Tween 80, oleic acid, propylene glycol, PEG 200, PEG 400, PEG 600, Transcutol, 2-pyrrolidone, DMSO) resulted relatively similar, being 1.6µg/cm(2) in case of oleic acid (solubility 74mg/ml) and 0.18µg/cm(2) in case of propylene glycol (solubility 0.60mg/ml). Permeation experiments on stripped skin (no stratum corneum) and isolated dermis as well as uptake experiments on isolated stratum corneum sheets demonstrated that IMQ accumulation is related to skin solvent uptake. Finally, microemulsions (MEs) prepared with the above-studied components demonstrated a very good performance. In particular, a ME composed of 10% oleic acid, 35% Transcutol, 35% Tween 80 and 20% water is able to accumulate the same amount of drug as the commercial formulation but with far more efficiency, since its concentration was 12 times lower.


Assuntos
Aminoquinolinas/administração & dosagem , Aminoquinolinas/metabolismo , Antineoplásicos/administração & dosagem , Antineoplásicos/metabolismo , Epiderme/metabolismo , Absorção Cutânea/fisiologia , Administração Cutânea , Animais , Epiderme/efeitos dos fármacos , Imiquimode , Absorção Cutânea/efeitos dos fármacos , Suínos
19.
Eur J Med Chem ; 122: 394-407, 2016 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-27394399

RESUMO

Synthetic quinoline derivatives continue to be considered as candidates for new drug discovery if they act against CQ-resistant strains of malaria even after the widespread emergence of resistance to CQ. In this study, we explored the activities of two series of new 4-aminoquinoline derivatives and found them to be effective against Plasmodium falciparum under in vitro conditions. Further, we selected four most active derivatives 1m, 1o, 2c and 2j and evaluated their antimalarial potential against Plasmodium berghei in vivo. These 4-aminoquinolines cured BALB/c mice infected with P. berghei. The ED50 values were calculated to be 2.062, 2.231, 1.431, 1.623 and 1.18 mg/kg of body weight for each of the compounds 1m, 1o, 2c, 2j and amodiaquine, respectively. Total doses of 500 mg/kg of body weight were well received. The study suggests that these new 4-aminoquinolines should be used for structure activity relationship to find lead molecules for treating multidrug-resistant Plasmodium falciparum and Plasmodium vivax.


Assuntos
Aminoquinolinas/síntese química , Aminoquinolinas/farmacologia , Antimaláricos/síntese química , Antimaláricos/farmacologia , Cloroquina/farmacologia , Resistência a Medicamentos/efeitos dos fármacos , Aminoquinolinas/química , Aminoquinolinas/metabolismo , Animais , Antimaláricos/química , Antimaláricos/metabolismo , Linhagem Celular Tumoral , Técnicas de Química Sintética , Análise Custo-Benefício , L-Lactato Desidrogenase/química , L-Lactato Desidrogenase/metabolismo , Masculino , Camundongos , Simulação de Acoplamento Molecular , Plasmodium falciparum/efeitos dos fármacos , Plasmodium falciparum/enzimologia , Plasmodium vivax/enzimologia , Relação Estrutura-Atividade
20.
J Med Chem ; 59(1): 264-81, 2016 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-26640981

RESUMO

The syntheses and antiplasmodial activities of various substituted aminoquinolines coupled to an adamantane carrier are described. The compounds exhibited pronounced in vitro and in vivo activity against Plasmodium berghei in the Thompson test. Tethering a fluorine atom to the aminoquinoline C(3) position afforded fluoroaminoquinolines that act as intrahepatocytic parasite inhibitors, with compound 25 having an IC50 = 0.31 µM and reducing the liver load in mice by up to 92% at 80 mg/kg dose. Screening our peroxides as inhibitors of liver stage infection revealed that the tetraoxane pharmacophore itself is also an excellent liver stage P. berghei inhibitor (78: IC50 = 0.33 µM). Up to 91% reduction of the parasite liver load in mice was achieved at 100 mg/kg. Examination of tetraoxane 78 against the transgenic 3D7 strain expressing luciferase under a gametocyte-specific promoter revealed its activity against stage IV-V Plasmodium falciparum gametocytes (IC50 = 1.16 ± 0.37 µM). To the best of our knowledge, compounds 25 and 78 are the first examples of either an 4-aminoquinoline or a tetraoxane liver stage inhibitors.


Assuntos
Aminoquinolinas/síntese química , Aminoquinolinas/farmacologia , Antimaláricos/síntese química , Antimaláricos/farmacologia , Tetraoxanos/síntese química , Tetraoxanos/farmacologia , Aminoquinolinas/metabolismo , Animais , Antimaláricos/metabolismo , Avaliação Pré-Clínica de Medicamentos , Canais de Potássio Éter-A-Go-Go/efeitos dos fármacos , Hemina/antagonistas & inibidores , Hepatócitos/metabolismo , Humanos , Técnicas In Vitro , Fígado/parasitologia , Camundongos , Microssomos Hepáticos/metabolismo , Carga Parasitária , Plasmodium berghei/efeitos dos fármacos , Plasmodium falciparum/efeitos dos fármacos , Relação Estrutura-Atividade , Tetraoxanos/metabolismo
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