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1.
J Immunol ; 207(6): 1672-1682, 2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34417259

RESUMO

NK cells are known to be developmentally blocked and functionally inhibited in patients with acute myeloid leukemia (AML), resulting in poor clinical outcomes. In this study, we demonstrate that whereas NK cells are inhibited, closely related type 1 innate lymphoid cells (ILC1s) are enriched in the bone marrow of leukemic mice and in patients with AML. Because NK cells and ILC1s share a common precursor (ILCP), we asked if AML acts on the ILCP to alter developmental potential. A combination of ex vivo and in vivo studies revealed that AML skewing of the ILCP toward ILC1s and away from NK cells represented a major mechanism of ILC1 generation. This process was driven by AML-mediated activation of the aryl hydrocarbon receptor (AHR), a key transcription factor in ILCs, as inhibition of AHR led to decreased numbers of ILC1s and increased NK cells in the presence of AML. These results demonstrate a mechanism of ILC developmental skewing in AML and support further preclinical study of AHR inhibition in restoring normal NK cell development and function in the setting of AML.


Assuntos
Diferenciação Celular/imunologia , Imunidade Inata , Células Matadoras Naturais/imunologia , Leucemia Mieloide Aguda/imunologia , Animais , Compostos Azo/farmacologia , Fatores de Transcrição Hélice-Alça-Hélice Básicos/agonistas , Fatores de Transcrição Hélice-Alça-Hélice Básicos/antagonistas & inibidores , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Medula Óssea/imunologia , Carbazóis/farmacologia , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Modelos Animais de Doenças , Feminino , Humanos , Leucemia Mieloide Aguda/sangue , Contagem de Linfócitos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pirazóis/farmacologia , Receptores de Hidrocarboneto Arílico/agonistas , Receptores de Hidrocarboneto Arílico/antagonistas & inibidores , Receptores de Hidrocarboneto Arílico/metabolismo , Transdução de Sinais/efeitos dos fármacos
2.
J Enzyme Inhib Med Chem ; 36(1): 1509-1520, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34238110

RESUMO

In the present study, a series of azo derivatives (TR-1 to TR-9) have been synthesised via the diazo-coupling approach between substituted aromatic amines with phenol or naphthol derivatives. The compounds were evaluated for their therapeutic applications against alpha-glucosidase (anti-diabetic) and pathogenic bacterial strains E. coli (gram-negative), S. aureus (gram-positive), S. aureus (gram-positive) drug-resistant strain, P. aeruginosa (gram-negative), P. aeruginosa (gram-negative) drug-resistant strain and P. vulgaris (gram-negative). The IC50 (µg/mL) of TR-1 was found to be most effective (15.70 ± 1.3 µg/mL) compared to the reference drug acarbose (21.59 ± 1.5 µg/mL), hence, it was further selected for the kinetic studies in order to illustrate the mechanism of inhibition. The enzyme inhibitory kinetics and mode of binding for the most active inhibitor (TR-1) was performed which showed that the compound is a non-competitive inhibitor and effectively inhibits the target enzyme by binding to its binuclear active site reversibly.


Assuntos
Antibacterianos/farmacologia , Compostos Azo/farmacologia , Inibidores Enzimáticos/farmacologia , Hipoglicemiantes/farmacologia , Simulação de Acoplamento Molecular , alfa-Glucosidases/metabolismo , Antibacterianos/síntese química , Antibacterianos/química , Compostos Azo/síntese química , Compostos Azo/química , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Escherichia coli/efeitos dos fármacos , Hipoglicemiantes/síntese química , Hipoglicemiantes/química , Cinética , Testes de Sensibilidade Microbiana , Estrutura Molecular , Pseudomonas aeruginosa/efeitos dos fármacos , Saccharomyces cerevisiae/enzimologia , Staphylococcus aureus/efeitos dos fármacos
3.
J Enzyme Inhib Med Chem ; 36(1): 1632-1645, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34289751

RESUMO

Nonsteroidal aromatase inhibitors (NSAIs) are well-established drugs for the therapy of breast cancer. However, they display some serious side effects, and their efficacy can be compromised by the development of chemoresistance. Previously, we have reported different indazole-based carbamates and piperidine-sulphonamides as potent aromatase inhibitors. Starting from the most promising compounds, here we have synthesised new indazole and triazole derivatives and evaluated their biological activity as potential dual agents, targeting both the aromatase and the inducible nitric oxide synthase, being this last dysregulated in breast cancer. Furthermore, selected compounds were evaluated as antiproliferative and cytotoxic agents in the MCF-7 cell line. Moreover, considering the therapeutic diversity of azole-based compounds, all the synthesized compounds were also evaluated as antifungals on different Candida strains. A docking study, as well as molecular dynamics simulation, were carried out to shed light on the binding mode of the most interesting compound into the different target enzymes catalytic sites.


Assuntos
Antifúngicos/farmacologia , Antineoplásicos/farmacologia , Inibidores da Aromatase/farmacologia , Compostos Azo/farmacologia , Neoplasias da Mama/tratamento farmacológico , Simulação de Acoplamento Molecular , Micoses/tratamento farmacológico , Antifúngicos/síntese química , Antifúngicos/química , Antineoplásicos/síntese química , Antineoplásicos/química , Inibidores da Aromatase/síntese química , Inibidores da Aromatase/química , Compostos Azo/síntese química , Compostos Azo/química , Candida/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Células MCF-7 , Estrutura Molecular , Relação Estrutura-Atividade
4.
Curr Opin Chem Biol ; 62: 119-129, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34118759

RESUMO

The ENCODE and genome-wide association projects have shown that much of the genome is transcribed into RNA and much less is translated into protein. These and other functional studies suggest that the druggable transcriptome is much larger than the druggable proteome. This review highlights approaches to define druggable RNA targets and structure-activity relationships across genomic RNA. Binding compounds can be identified and optimized into structure-specific ligands by using sequence-based design with various modes of action, for example, inhibiting translation or directing pre-mRNA splicing outcomes. In addition, strategies to direct protein activity against an RNA of interest via chemically induced proximity is a burgeoning area that has been validated both in cells and in preclinical animal models, and we describe that it may allow rapid access to new avenues to affect RNA biology. These approaches and the unique modes of action suggest that more RNAs are potentially amenable to targeting than proteins.


Assuntos
Antineoplásicos/química , Genoma/efeitos dos fármacos , RNA/metabolismo , Bibliotecas de Moléculas Pequenas/química , Transcriptoma/efeitos dos fármacos , Animais , Antineoplásicos/farmacologia , Compostos Azo/farmacologia , Sequência de Bases , Desenho de Fármacos , Regulação Neoplásica da Expressão Gênica , Genoma/genética , Estudo de Associação Genômica Ampla , Genômica , Humanos , Ligantes , Modelos Animais , Pirimidinas/farmacologia , Bibliotecas de Moléculas Pequenas/metabolismo , Relação Estrutura-Atividade , Transcriptoma/genética
5.
J Biochem Mol Toxicol ; 35(8): e22821, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34036678

RESUMO

The preservation of the redox homeostasis is critical for cell survival and functionality. Redox imbalance is an essential inducer of several pathological states. CD4+ /helper T cells are highly dependent on the redox state of their surrounding milieu. The potential of the aryl hydrocarbon receptor (AhR) engagement in controlling CD4+ T-cell fate during redox alteration is still challenging. C57BL/6 mice were treated with AhR agonist 6-formylindolo[3,2-b]carbazole (FICZ), AhR antagonist CH223191, an inhibitor of glutathione biosynthesis buthionine sulfoximine (BSO), and the antioxidant N-acetylcysteine (NAC) alone or in combination. Six days later, splenocytes were evaluated for the expression of the redox-related genes and the possible changes in T-cell subsets. FICZ like BSO significantly elevated the expression of HMOX1, GCLC, and GCLM genes but it failed to increase the expression of the Nrf2 gene. Moreover, FICZ + BSO increased while FICZ + CH223191 or NAC decreased the expression of these genes. FICZ also significantly increased Th1 cell numbers but decreased Tregs in a dose-dependent manner. Furthermore, a high dose of FICZ + CH223191 + NAC significantly enhanced Th1, Th17, and Treg cells but its low dose in such a situation increased Th2 and Th17 while decreased Treg cells. AhR engagement during redox alteration can determine the fate of CD4 + T cells, so, AhR agonists or antagonists might be useful in assessing immune responses. However, these results need further verifications in vitro and in animal models of various diseases.


Assuntos
Receptores de Hidrocarboneto Arílico , Linfócitos T Auxiliares-Indutores/metabolismo , Acetilcisteína/farmacologia , Animais , Compostos Azo/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Glutamato-Cisteína Ligase/biossíntese , Heme Oxigenase-1/biossíntese , Proteínas de Membrana/biossíntese , Camundongos , Fator 2 Relacionado a NF-E2/biossíntese , Oxirredução/efeitos dos fármacos , Pirazóis/farmacologia , Receptores de Hidrocarboneto Arílico/agonistas , Receptores de Hidrocarboneto Arílico/metabolismo
6.
J Biol Inorg Chem ; 26(4): 435-453, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33934217

RESUMO

The synthesis and characterization of four platinum(II) complexes using azobenzenes conveniently functionalized as ligands has been carried out. The characteristic photochemical behavior of the complexes due to the presence of azobenzene-type ligands and the role of the ligands in the activation of the complexes has been studied. Their promising cytotoxicity observed in HeLa cells prompted us to study the mechanism of action of these complexes as cytostatic agents. The interaction of the compounds with DNA, studied by circular dichroism, revealed a differential activity of the Pt(II) complexes upon irradiation. The intercalation abilities of the complexes as well as their reactivity with common proteins present in the blood stream allows to confirm some of the compounds obtained as good anticancer candidates.


Assuntos
Compostos Azo/farmacologia , Compostos de Platina/farmacologia , Antineoplásicos , Compostos Azo/química , Sobrevivência Celular/efeitos dos fármacos , Complexos de Coordenação , Desenho de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Células HeLa , Humanos , Espectrometria de Massas , Compostos de Platina/síntese química , Compostos de Platina/química
7.
Mol Med Rep ; 23(6)2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33899121

RESUMO

The present study evaluated indoleamine 2,3­dioxygenase 1 (IDO) kinetics and how it affects cell survival during the two distinct phases of ischemia­reperfusion (I­R) injury. Primary renal proximal tubular epithelial cells (RPTECs) were cultured under anoxia or reoxygenation with or without the IDO inhibitor 1­DL­methyltryptophan, the aryl­hydrocarbon receptor (AhR) inhibitor CH223191 or the ferroptosis inhibitor α­tocopherol. Using cell imaging, colorimetric assays, PCR and western blotting, it was demonstrated that IDO was upregulated and induced apoptosis during anoxia. The related molecular pathway entails tryptophan degradation, general control non­derepressible­2 kinase (GCN2K) activation, increased level of phosphorylated eukaryotic translation initiation factor 2α, activating transcription factor (ATF)4, ATF3, C/EBP homologous protein, phosphorylated p53, p53, Bax, death receptor­5 and eventually activated cleaved caspase­3. Reoxygenation also upregulated IDO, which, in this case, induced ferroptosis. The related molecular pathway encompasses kynurenine production, AhR activation, cytochrome p450 enzymes increase, reactive oxygen species generation and eventually ferroptosis. In conclusion, in RPTECs, both anoxia and reoxygenation upregulated IDO, which in turn induced GCN2K­mediated apoptosis and AhR­mediated ferroptosis. Since both phases of I­R injury share IDO upregulation as a common point, its inhibition may prove a useful therapeutic strategy for preventing or attenuating I­R injury.


Assuntos
Hipóxia Celular , Células Epiteliais/metabolismo , Indolamina-Pirrol 2,3,-Dioxigenase/metabolismo , Túbulos Renais Proximais/citologia , Fator 3 Ativador da Transcrição/metabolismo , Fator 4 Ativador da Transcrição/metabolismo , Animais , Apoptose , Compostos Azo/farmacologia , Proteínas Estimuladoras de Ligação a CCAAT/metabolismo , Células Cultivadas , Inibidores Enzimáticos/farmacologia , Células Epiteliais/efeitos dos fármacos , Ferroptose , Indolamina-Pirrol 2,3,-Dioxigenase/antagonistas & inibidores , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Serina-Treonina Quinases/metabolismo , Pirazóis/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Receptores de Hidrocarboneto Arílico/antagonistas & inibidores , Receptores de Hidrocarboneto Arílico/metabolismo
8.
Parasitol Res ; 120(6): 2087-2094, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33864105

RESUMO

Control and treatment of onchocerciasis, a devastating tropical filarial disease caused by Onchocerca volvulus, rely solely on the community directed treatment with ivermectin. However, ivermectin is only microfilaricidal with evidence of resistance of the parasite among other limitations, which necessitate the search for new efficacious and safe filaricides. Ten synthetic thienylazoryl dyes were screened in vitro against adult and microfilariae worm stages of Onchocerca ochengi based on worm motility and MTT formazan assay. Cytotoxicity of active compounds was assessed on monkey kidney epithelial cells (LLC-MK2) using the MTT formazan assay. Seven (7) compounds showed both macrofilaricidal activity against adult male worms and microfilaricidal activity among which three 4a, 4c and 4e recorded the highest activity (IC50 = 4.2 to 8.8µM) against adult male worms, comparable to some standard anthelmintics. Five compounds showed rapid activity against microfilariae with 100% inhibition after 24-h incubation. The active compounds were nontoxic on monkey kidney cells (CC50> 4µg/mL), but their selectivity index values were relatively low (≤ 3). The thienylazoaryls with both macrofilaricidal and microfilaricidal activities may yield molecules which could be used for eradication of onchocerciasis following further medicinal chemistry modification of their structures to enhance their selectivity.


Assuntos
Compostos Azo/farmacologia , Filaricidas/farmacologia , Microfilárias/efeitos dos fármacos , Onchocerca/efeitos dos fármacos , Tiofenos/farmacologia , Animais , Compostos Azo/química , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Concentração Inibidora 50 , Masculino , Tiofenos/química
9.
Int J Mol Sci ; 22(6)2021 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-33802075

RESUMO

The high biological activity of the chromene compounds coupled with the intriguing optical features of azo chromophores prompted our desire to construct novel derivatives of chromene incorporating azo moieties 4a-l, which have been prepared via a three-component reaction of 1-naphthalenol-4-[(4-ethoxyphenyl) azo], 1, with the benzaldehyde derivatives and malononitrile. The structural identities of the azo-chromene 4a-l were confirmed on the basis of their spectral data and elemental analysis, and a UV-visible study was performed in a Dimethylformamide (DMF) solution for these molecules. Additionally, the antimicrobial activity was investigated against four human pathogens (Gram-positive and Gram-negative bacteria) and four fungi, employing an agar well diffusion method, with their minimum inhibitory concentrations being reported. Molecules 4a, 4g, and 4h were discovered to be more efficacious against Syncephalastrum racemosum (RCMB 05922) in comparison to the reference drugs, while compounds 4b and 4h demonstrated the highest inhibitory activity against Escherichia coli (E. coli) in evaluation against the reference drugs. Moreover, their cytotoxicity was assessed against three different human cell lines, including human colon carcinoma (HCT-116), human hepatocellular carcinoma (HepG-2), and human breast adenocarcinoma (MCF-7) with a selection of molecules illustrating potency against the HCT-116 and MCF-7 cell lines. Furthermore, the molecular modeling results depicted the binding interactions of the synthesized compounds 3b and 3h in the active site of the E. coli DNA gyrase B enzyme with a clear SAR (structure-activity relationship) analysis. Lastly, the density functional theory's (DFTs) theoretical calculations were performed to quantify the energy levels of the Frontier Molecular Orbitals (FMOs) and their energy gaps, dipole moments, and molecular electrostatic potentials. These data were utilized in the chemical descriptor estimations to confirm the biological activity.


Assuntos
Anti-Infecciosos , Antineoplásicos , Compostos Azo , Benzopiranos , Proliferação de Células/efeitos dos fármacos , Simulação por Computador , Escherichia coli/crescimento & desenvolvimento , Mucorales/crescimento & desenvolvimento , Neoplasias/tratamento farmacológico , Anti-Infecciosos/síntese química , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia , Compostos Azo/síntese química , Compostos Azo/química , Compostos Azo/farmacologia , Benzopiranos/síntese química , Benzopiranos/química , Benzopiranos/farmacologia , Células HCT116 , Células Hep G2 , Humanos , Células MCF-7 , Neoplasias/metabolismo , Neoplasias/patologia
10.
ACS Appl Mater Interfaces ; 13(12): 14543-14551, 2021 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-33733728

RESUMO

Development of smart switchable surfaces to solve the inevitable bacteria attachment and colonization has attracted much attention; however, it proves very challenging to achieve on-demand regeneration for noncontaminated surfaces. We herein report a smart, host-guest interaction-mediated photo/temperature dual-controlled antibacterial surface, topologically combining stimuli-responsive polymers with nanobactericide. From the point of view of long-chain polymer design, the peculiar hydration layer generated by hydrophilic poly(2-hydroxyethyl methacrylate) (polyHEMA) segments severs the route of initial bacterial attachment and subsequent proliferation, while the synergistic effect on chain conformation transformation poly(N-isopropylacrylamide) (polyNIPAM) and guest complex dissociation azobenzene/cyclodextrin (Azo/CD) complex greatly promotes the on-demand bacterial release in response to the switch of temperature and UV light. Therefore, the resulting surface exhibits triple successive antimicrobial functions simultaneously: (i) resists ∼84.9% of initial bacterial attachment, (ii) kills ∼93.2% of inevitable bacteria attack, and (iii) releases over 94.9% of killed bacteria even after three cycles. The detailed results not only present a potential and promising strategy to develop renewable antibacterial surfaces with successive antimicrobial functions but also contribute a new antimicrobial platform to biomedical or surgical applications.


Assuntos
Antibacterianos/química , Compostos Azo/química , Materiais Biocompatíveis/química , Ciclodextrinas/química , Polímeros/química , Antibacterianos/farmacologia , Compostos Azo/farmacologia , Bactérias/efeitos dos fármacos , Infecções Bacterianas/prevenção & controle , Materiais Biocompatíveis/farmacologia , Ciclodextrinas/farmacologia , Humanos , Interações Hidrofóbicas e Hidrofílicas , Nanoestruturas/química , Poli-Hidroxietil Metacrilato/química , Poli-Hidroxietil Metacrilato/farmacologia , Polímeros/farmacologia , Temperatura , Raios Ultravioleta
11.
Front Immunol ; 12: 630427, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33659010

RESUMO

Cigarette smoke is a prevalent respiratory toxicant that remains a leading cause of death worldwide. Cigarette smoke induces inflammation in the lungs and airways that contributes to the development of diseases such as lung cancer and chronic obstructive pulmonary disease (COPD). Due to the presence of aryl hydrocarbon receptor (AhR) ligands in cigarette smoke, activation of the AhR has been implicated in driving this inflammatory response. However, we have previously shown that the AhR suppresses cigarette smoke-induced pulmonary inflammation, but the mechanism by which the AhR achieves its anti-inflammatory function is unknown. In this study, we use the AhR antagonist CH-223191 to inhibit AhR activity in mice. After an acute (3-day) cigarette smoke exposure, AhR inhibition was associated with significantly enhanced neutrophilia in the airways in response to cigarette smoke, mimicking the phenotype of AhR-deficient mice. We then used genetically-modified mouse strains which express an AhR that can bind ligand but either cannot translocate to the nucleus or bind its cognate response element, to show that these features of the AhR pathway are not required for the AhR to suppress pulmonary neutrophilia. Finally, using the non-toxic endogenous AhR ligand FICZ, we provide proof-of-concept that activation of pulmonary AhR attenuates smoke-induced inflammation. Collectively, these results support the importance of AhR activity in mediating its anti-inflammatory function in response to cigarette smoke. Further investigation of the precise mechanisms by which the AhR exerts is protective functions may lead to the development of therapeutic agents to treat people with chronic lung diseases that have an inflammatory etiology, but for which few therapeutic options exist.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/fisiologia , Dioxinas/farmacologia , Neutrófilos/patologia , Doença Pulmonar Obstrutiva Crônica/prevenção & controle , Receptores de Hidrocarboneto Arílico/fisiologia , Elementos de Resposta/fisiologia , Fumaça/efeitos adversos , Tabaco/efeitos adversos , Doença Aguda , Animais , Compostos Azo/farmacologia , Carbazóis/farmacologia , Feminino , Masculino , Camundongos , Pirazóis/farmacologia
12.
Org Biomol Chem ; 19(10): 2312-2321, 2021 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-33634812

RESUMO

Photopharmacology develops bioactive compounds whose pharmacological potency can be regulated by light. The concept relies on the introduction of molecular photoswitches, such as azobenzenes, into the structure of bioactive compounds, such as known enzyme inhibitors. Until now, the development of photocontrolled protein kinase inhibitors proved to be challenging for photopharmacology. Here, we describe a new class of heterocyclic azobenzenes based on the longdaysin scaffold, which were designed to photo-modulate the activity of casein kinase Iα (CKIα) in the context of photo-regulation of circadian rhythms. Evaluation of a set of photoswitchable longdaysin derivatives allowed for better insight into the relationship between substituents and thermal stability of the cis-isomer. Furthermore, our studies on the chemical stability of the azo group in this type of heterocyclic azobenzenes showed that they undergo a fast reduction to the corresponding hydrazines in the presence of different reducing agents. Finally, we attempted light-dependent modulation of CKIα activity together with the accompanying modulation of cellular circadian rhythms in which CKIα is directly involved. Detailed structure-activity relationship (SAR) analysis revealed a new potent reduced azopurine with a circadian period lengthening effect more pronounced than that of its parent molecule, longdaysin. Altogether, the results presented here highlight the challenges in the development of light-controlled kinase inhibitors for the photomodulation of circadian rhythms and reveal key stability issues for using the emerging class of heteroaryl azobenzenes in biological applications.


Assuntos
Compostos Azo/farmacologia , Caseína Quinase Ialfa/antagonistas & inibidores , Ritmo Circadiano/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Purinas/farmacologia , Compostos Azo/química , Compostos Azo/efeitos da radiação , Linhagem Celular Tumoral , Humanos , Isomerismo , Luz , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/efeitos da radiação , Purinas/química , Purinas/efeitos da radiação , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/farmacologia , Bibliotecas de Moléculas Pequenas/efeitos da radiação , Relação Estrutura-Atividade
13.
Chem Pharm Bull (Tokyo) ; 69(1): 67-71, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33390522

RESUMO

We examined the method of oxidative hemolysis for assessment of antioxidant activity of various compounds, especially lipophilic compounds. 2,2'-Azobis(amidinopropane) dihydrochloride (AAPH) was used as the source of free radicals for the oxidative hemolysis of horse erythrocytes. We found that absorbance at 540 nm is not appropriate for monitoring AAPH-induced hemolysis. Instead, we should use absorbance at 523 nm (an isosbestic point), because AAPH oxidizes the oxygenated hemoglobin to methemoglobin and absorbance at 540 nm does not correctly reflect the amount of released hemoglobin by AAPH-induced hemolysis. The corrected method of AAPH-induced hemolysis was applicable to assess the antioxidant activity of various hydrophilic compounds such as ascorbic acid, (-)-epicatechin, and edaravone. For the assessment of antioxidant activity of lipophilic compounds, we need appropriate dispersing agents for these lipophilic compounds. Among several agents tested, 1,2-dimiristoyl-sn-glycero-3-phosphocholine (DMPC) liposome at a concentration of 0.34 mM was found to be useful. Exogenous α-tocopherol incorporated using DMPC liposome as a dispersing agent was shown to protect erythrocytes from AAPH-induced hemolysis in a concentration-dependent manner.


Assuntos
Antioxidantes/farmacologia , Compostos Azo/farmacologia , Eritrócitos/efeitos dos fármacos , Animais , Antioxidantes/química , Compostos Azo/química , Relação Dose-Resposta a Droga , Eritrócitos/metabolismo , Hemólise/efeitos dos fármacos , Cavalos , Interações Hidrofóbicas e Hidrofílicas
14.
J Med Chem ; 64(2): 1018-1036, 2021 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-33423463

RESUMO

Tetrazanbigen (TNBG) is a novel sterol isoquinoline derivative with poor water solubility and moderate inhibitory effects on human cancer cell lines via lipoapoptosis induction. Herein, we developed a series of novel TNBG analogues with improved water solubility and antiproliferative activities. The CCK-8 assay enabled us to identify a novel compound, 14g, which strongly inhibited HepG2 and A549 cell growth with IC50 values of 0.54 and 0.47 µM, respectively. The anticancer effects might be explained by the partial activation and upregulation of PPARγ expression, as indicated by the transactivation assay and western blotting evaluation. Furthermore, the in vitro antiproliferative activity was verified in an in vivo xenograft model in which 14g strongly reduced tumor growth at a dose of 10 mg/kg. In line with these positive observations, 14g exhibited an excellent water solubility of 31.4 mg/mL, which was more than 1000-fold higher than that of TNBG (4 µg/mL). Together, these results suggest that 14g is a promising anticancer therapeutic that deserves further investigation.


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Compostos Azo/química , Compostos Azo/farmacologia , Gonanos/química , Gonanos/farmacologia , PPAR gama/agonistas , Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Desenho de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Modelos Moleculares , Solubilidade , Relação Estrutura-Atividade , Ensaio Tumoral de Célula-Tronco , Vacúolos/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
16.
Prep Biochem Biotechnol ; 51(1): 16-27, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32633607

RESUMO

The spore laccase enzyme production by B. amyloliquefaciens was optimized. It was characterized and tested for its textile dye decolorization potential. LB medium was found to be the most promising growth medium with addition of glucose (1-2%), yeast extract (0.1%), FeCl3 (0.01 mM) and MnCl2 (0.001 mM). The optimum spore laccase production was at pH 8, 30 °C, 1:5 medium to air ratio, 2% inoculum size and 7 days incubation. The characterization study of the enzyme showed the maximum activity at 60 °C and pH 6-7.5. It was induced by Ca+2, Mg+2, Fe+3, Zn+2, Cu+2 and Na+ at 1 mM concentration. Also, it was stable in the presence of methanol, ethanol, acetone and chloroform. In addition, it enhanced about 34% by 5 mM H2O2 and it was nearly stable at 10-20 mM H2O2. Furthermore, mediators such as ABTS, syrengaldazine and 2, 6 dimethyl phenol enhanced the spore laccase activity. The spore laccase enzyme efficiently decolorized direct red 81 and acid black 24 after 24 h. Phytotoxicity of the direct red 81 solution after decolorization by tested spore laccase was lower than that of the untreated dye solution. Finally, this study added a promising spore laccase candidate for ecofriendly and cost-effective dye wastewater bio-decolorization.


Assuntos
Bacillus amyloliquefaciens/enzimologia , Bacillus amyloliquefaciens/isolamento & purificação , Corantes/metabolismo , Lacase/metabolismo , Esporos Bacterianos/enzimologia , Têxteis , Águas Residuárias/microbiologia , Descoloração da Água/métodos , Poluentes Químicos da Água/metabolismo , Compostos Azo/metabolismo , Compostos Azo/farmacologia , Biodegradação Ambiental , Corantes/farmacologia , Meios de Cultura , Temperatura Alta , Peróxido de Hidrogênio/química , Concentração de Íons de Hidrogênio , Lens (Planta)/efeitos dos fármacos , Sementes/efeitos dos fármacos , Poluentes Químicos da Água/farmacologia
17.
Chemistry ; 27(7): 2439-2451, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33078454

RESUMO

Light regulation of drug molecules has gained growing interest in biochemical and pharmacological research in recent years. In addition, a serious need for novel molecular targets of antibiotics has emerged presently. Herein, the development of a photocontrollable, azobenzene-based antibiotic precursor towards tryptophan synthase (TS), an essential metabolic multienzyme complex in bacteria, is presented. The compound exhibited moderately strong inhibition of TS in its E configuration and five times lower inhibition strength in its Z configuration. A combination of biochemical, crystallographic, and computational analyses was used to characterize the inhibition mode of this compound. Remarkably, binding of the inhibitor to a hitherto-unconsidered cavity results in an unproductive conformation of TS leading to noncompetitive inhibition of tryptophan production. In conclusion, we created a promising lead compound for combatting bacterial diseases, which targets an essential metabolic enzyme, and whose inhibition strength can be controlled with light.


Assuntos
Compostos Azo/farmacologia , Inibidores Enzimáticos/farmacologia , Triptofano Sintase/antagonistas & inibidores , Inibidores Enzimáticos/efeitos da radiação
18.
Eur J Med Chem ; 209: 112920, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33049606

RESUMO

Safirinium P and Q fluorescence labels were synthesized and conjugated with spacered triterpenoic acids to access hybrid structures. While the parent safirinium compounds were not cytotoxic at all, many triterpenoid safirinium P and Q conjugates showed moderate cytotoxicity. An exception, however, was safirinium P derived compound 30 holding low EC50 = 5.4 µM (for A375 cells) to EC50 = 7.5 µM (for FaDu cells) as well as EC50 = 6.6 µM for non-malignant fibroblasts NIH 3T3. Fluorescence imaging showed that the safirinium core structures cannot enter the cells (not even after a prolonged incubation time of 24 h), while the conjugates (as exemplified for 30) are accumulating in the endoplasmic reticulum but not in the mitochondria. The development of safirinium-hybrids targeting the endoplasmic reticulum can be regarded as a promising strategy in the development of cytotoxic agents.


Assuntos
Antineoplásicos/farmacologia , Compostos Azo/farmacologia , Retículo Endoplasmático/efeitos dos fármacos , Triterpenos/farmacologia , Animais , Antineoplásicos/síntese química , Compostos Azo/síntese química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Corantes Fluorescentes/química , Humanos , Camundongos , Mitocôndrias/efeitos dos fármacos , Terapia de Alvo Molecular , Imagem Óptica , Piperazina/química , Relação Estrutura-Atividade , Triterpenos/síntese química
19.
Mol Med Rep ; 23(1)2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33179104

RESUMO

During the reperfusion phase of ischemia­reperfusion injury, reactive oxygen species (ROS) production aggravates the course of many diseases, including acute kidney injury. Among the various enzymes implicated in ROS production are the enzymes of the cytochromes P450 superfamily (CYPs). Since arylhydrocarbon receptor (AhR) controls the expression of certain CYPs, the involvement of this pathway was evaluated in reperfusion injury. Because AhR may interact with the nuclear factor erythroid 2­related factor 2 (Nrf2) and the hypoxia­inducible factor­1α (HIF­1α), whether such an interaction takes place and affects reperfusion injury was also assessed. Proximal renal proximal tubular epithelial cells were subjected to anoxia and subsequent reoxygenation. At the onset of reoxygenation, the AhR inhibitor CH223191, the HIF­1α activator roxadustat, or the ferroptosis inhibitor α­tocopherol were used. The activity of AhR, Nrf2, HIF­1α, and their transcriptional targets were assessed with western blotting. ROS production, lipid peroxidation and cell death were measured with colorimetric assays or cell imaging. Reoxygenation induced ROS production, lipid peroxidation and cell ferroptosis, whereas CH223191 prevented all. Roxadustat did not affect the above parameters. Reoxygenation activated AhR and increased CYP1A1, while CH223191 prevented both. Reoxygenation with or without CH223191 did not alter Nrf2 or HIF­1α activity. Thus, AhR is activated during reoxygenation and induces ROS production, lipid peroxidation and ferroptotic cell death. These detrimental effects may be mediated by AhR­induced CYP overexpression, while the Nrf2 or the HIF­1α pathways remain unaffected. Accordingly, the AhR pathway may represent a promising therapeutic target for the prevention of reperfusion injury.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Túbulos Renais Proximais/citologia , Oxigênio/efeitos adversos , Espécies Reativas de Oxigênio/metabolismo , Receptores de Hidrocarboneto Arílico/metabolismo , Traumatismo por Reperfusão/metabolismo , Animais , Compostos Azo/farmacologia , Hipóxia Celular , Células Cultivadas , Citocromo P-450 CYP1A1/metabolismo , Células Epiteliais/citologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Ferroptose , Glicina/análogos & derivados , Glicina/farmacologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Isoquinolinas/farmacologia , Túbulos Renais Proximais/efeitos dos fármacos , Túbulos Renais Proximais/metabolismo , Peroxidação de Lipídeos , Camundongos , Modelos Biológicos , Fator 2 Relacionado a NF-E2/metabolismo , Oxigênio/farmacologia , Pirazóis/farmacologia , Traumatismo por Reperfusão/induzido quimicamente , alfa-Tocoferol/farmacologia
20.
Int J Mol Sci ; 21(23)2020 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-33255816

RESUMO

In this study, we aimed at the application of the concept of photopharmacology to the approved vascular endothelial growth factor receptor (VEGFR)-2 kinase inhibitor axitinib. In a previous study, we found out that the photoisomerization of axitinib's stilbene-like double bond is unidirectional in aqueous solution due to a competing irreversible [2+2]-cycloaddition. Therefore, we next set out to azologize axitinib by means of incorporating azobenzenes as well as diazocine moieties as photoresponsive elements. Conceptually, diazocines (bridged azobenzenes) show favorable photoswitching properties compared to standard azobenzenes because the thermodynamically stable Z-isomer usually is bioinactive, and back isomerization from the bioactive E-isomer occurs thermally. Here, we report on the development of different sulfur-diazocines and carbon-diazocines attached to the axitinib pharmacophore that allow switching the VEGFR-2 activity reversibly. For the best sulfur-diazocine, we could verify in a VEGFR-2 kinase assay that the Z-isomer is biologically inactive (IC50 >> 10,000 nM), while significant VEGFR-2 inhibition can be observed after irradiation with blue light (405 nm), resulting in an IC50 value of 214 nM. In summary, we could successfully develop reversibly photoswitchable kinase inhibitors that exhibit more than 40-fold differences in biological activities upon irradiation. Moreover, we demonstrate the potential advantage of diazocine photoswitches over standard azobenzenes.


Assuntos
Axitinibe/química , Compostos Azo/farmacologia , Neoplasias/tratamento farmacológico , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/genética , Axitinibe/farmacologia , Compostos Azo/química , Carbono/química , Humanos , Isomerismo , Luz , Neoplasias/genética , Processos Fotoquímicos/efeitos dos fármacos , Estilbenos/química , Enxofre/química , Termodinâmica , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Água/química
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