RESUMO
Natural products have always served as an important source of drugs for treating various diseases. Among various privileged natural product scaffolds, the benzopyrone class of compounds has a substantial presence among biologically active compounds. One of the pioneering anticoagulant drugs, warfarin approved in 1954 bears a benzo-α-pyrone (coumarin) nucleus. The widely investigated psoriasis drugs, methoxsalen, and trioxsalen, also contain a benzo-α-pyrone nucleus. Benzo-γ-pyrone (chromone) containing drugs, cromoglic acid, and pranlukast were approved as treatments for asthma in 1982 and 2007, respectively. Numerous other small molecules with a benzopyrone core are under clinical investigation. The present review discusses the discovery, absorption, distribution, metabolism, excretion properties, and synthetic approaches for the Food and Drug Administration-approved and clinical-stage benzopyrone class of compounds. The role of the pyrone core in biological activity has also been discussed. The present review unravels the potential of benzopyrone core in medicinal chemistry and drug development.
Assuntos
Aprovação de Drogas , Descoberta de Drogas , United States Food and Drug Administration , Humanos , Estados Unidos , Animais , Pironas/química , Pironas/farmacologiaRESUMO
Many viruses utilize the host endo-lysosomal network for infection. Tracing the endocytic itinerary of SARS-CoV-2 can provide insights into viral trafficking and aid in designing new therapeutic strategies. Here, we demonstrate that the receptor binding domain (RBD) of SARS-CoV-2 spike protein is internalized via the pH-dependent CLIC/GEEC (CG) endocytic pathway in human gastric-adenocarcinoma (AGS) cells expressing undetectable levels of ACE2. Ectopic expression of ACE2 (AGS-ACE2) results in RBD traffic via both CG and clathrin-mediated endocytosis. Endosomal acidification inhibitors like BafilomycinA1 and NH4Cl, which inhibit the CG pathway, reduce the uptake of RBD and impede Spike-pseudoviral infection in both AGS and AGS-ACE2 cells. The inhibition by BafilomycinA1 was found to be distinct from Chloroquine which neither affects RBD uptake nor alters endosomal pH, yet attenuates Spike-pseudovirus entry. By screening a subset of FDA-approved inhibitors for functionality similar to BafilomycinA1, we identified Niclosamide as a SARS-CoV-2 entry inhibitor. Further validation using a clinical isolate of SARS-CoV-2 in AGS-ACE2 and Vero cells confirmed its antiviral effect. We propose that Niclosamide, and other drugs which neutralize endosomal pH as well as inhibit the endocytic uptake, could provide broader applicability in subverting infection of viruses entering host cells via a pH-dependent endocytic pathway.
Assuntos
Tratamento Farmacológico da COVID-19 , COVID-19/virologia , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/patogenicidade , Internalização do Vírus/efeitos dos fármacos , Cloreto de Amônio/farmacologia , Enzima de Conversão de Angiotensina 2/genética , Enzima de Conversão de Angiotensina 2/fisiologia , Animais , Antivirais/administração & dosagem , Antivirais/farmacologia , Linhagem Celular , Chlorocebus aethiops , Cloroquina/farmacologia , Clatrina/metabolismo , Sinergismo Farmacológico , Endocitose/efeitos dos fármacos , Endocitose/fisiologia , Endossomos/efeitos dos fármacos , Endossomos/metabolismo , Humanos , Concentração de Íons de Hidrogênio/efeitos dos fármacos , Hidroxicloroquina/administração & dosagem , Macrolídeos/farmacologia , Niclosamida/administração & dosagem , Niclosamida/farmacologia , Ligação Proteica/efeitos dos fármacos , Domínios Proteicos , SARS-CoV-2/fisiologia , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/fisiologia , Células VeroRESUMO
Caffeine is one of the privileged natural products that shows numerous effects on the central nervous system. Herein, thirty-one caffeine-based amide derivatives were synthesized and evaluated in vitro for their anticholinesterase activity. The introduction of the amide group to the caffeine core augmented its anticholinesterase activity from an IC50 value of 128 to 1.32 µM (derivative, 6i). The SAR study revealed that N7 substitution on caffeine core is favorable over N1, and the presence of amide 'carbonyl' as a part of the linker contributes to the biological activity. The caffeine core of 6i exhibits interactions with the peripheral anionic site, whereas the N-benzyl ring fits nicely inside the catalytic anionic site. Analog 6i inhibits AChE in a mixed-type mode (Ki 4.58 µM) and crosses the BBB in an in-vitro PAMPA assay. Compound 6i has a descent metabolic stability in MLM (>70% remaining after 30 min) and favorable oral pharmacokinetics in Swiss albino mice.
Assuntos
Doença de Alzheimer , Inibidores da Colinesterase , Camundongos , Animais , Inibidores da Colinesterase/farmacologia , Inibidores da Colinesterase/metabolismo , Cafeína/farmacologia , Acetilcolinesterase/metabolismo , Barreira Hematoencefálica , Amidas/farmacologia , Amidas/metabolismo , Simulação de Acoplamento Molecular , Doença de Alzheimer/metabolismo , Relação Estrutura-AtividadeRESUMO
Berberrubine is a naturally occurring isoquinoline alkaloid and a bioactive metabolite of berberine. Berberine exhibits a wide range of pharmacological activities, including cholinesterase inhibition. The cholinesterase inhibitors provide symptomatic treatment for Alzheimer's disease; however, multitarget-directed ligands have the potential as disease-modifying therapeutics. Herein, we prepared a series of C9-substituted berberrubine derivatives intending to discover dual cholinesterase and beta-site amyloid-precursor protein cleaving enzyme 1 (BACE-1) inhibitors. Most synthesized derivatives possessed balanced dual inhibition (AChE and BChE) activity in the submicromolar range and a moderate inhibition against BACE-1. Two most active ester derivatives, 12a and 11d, display inhibition of AChE, BChE, and BACE-1. The 3-methoxybenzoyl ester derivative, 12a, inhibits electric eel acetylcholinesterase (EeAChE), equine serum butyrylcholinesterase (eqBChE), and human hBACE-1 with IC50 values of 0.5, 4.3, and 11.9 µM, respectively and excellent BBB permeability (Pe = 8 × 10-6 cm/s). The ester derivative 12a is metabolically unstable; however, its ether analog 13 is stable in HLM and exhibits inhibition of AChE, BChE, and BACE-1 with IC50 values of 0.44, 3.8, and 17.9 µM, respectively. The ether analog also inhibits self-aggregation of Aß and crosses BBB (Pe = 7.3 × 10-6 cm/s). Administration of 13 at 5 mg/kg (iv) in Wistar rats showed excellent plasma exposure with AUC0-∞ of 28,834 ng min/ml. In conclusion, the multitargeted berberrubine ether derivative 13 is CNS permeable and has good ADME properties.
Assuntos
Doença de Alzheimer , Berberina , Ratos , Animais , Cavalos , Humanos , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Butirilcolinesterase/metabolismo , Acetilcolinesterase/metabolismo , Berberina/farmacologia , Relação Estrutura-Atividade , Éter/uso terapêutico , Simulação de Acoplamento Molecular , Ratos Wistar , Inibidores da Colinesterase , Etil-Éteres/uso terapêutico , Éteres/uso terapêutico , Estrutura MolecularRESUMO
Kinases have gained an important place in the list of vital therapeutic targets because of their overwhelming clinical success in the last two decades. Among various clinically validated kinases, the cyclin-dependent kinases (CDK) are one of the extensively studied drug targets for clinical development. Food and Drug Administration has approved three CDK inhibitors for therapeutic use, and at least 27 inhibitors are under active clinical development. In the last decade, research and development in this area took a rapid pace, and thus the analysis of scaffold diversity is essential for future drug design. Available reviews lack the systematic study and discussion on the scaffold diversity of CDK inhibitors. Herein we have reviewed and critically analyzed the chemical diversity present in the preclinical and clinical pipeline of CDK inhibitors. Our analysis has shown that although several scaffolds represent CDK inhibitors, only the amino-pyrimidine is a well-represented scaffold. The three-nitrogen framework of amino-pyrimidine is a fundamental hinge-binding unit. Further, we have discussed the selectivity aspects among CDKs, the clinical trial dose-limiting toxicities, and highlighted the most advanced clinical candidates. We also discuss the changing paradigm towards selective inhibitors and an overview of ATP-binding pockets of all druggable CDKs. We carefully analyzed the clinical pipeline to unravel the candidates that are currently under active clinical development. In addition to the plenty of dual CDK4/6 inhibitors, there are many selective CDK7, CDK9, and CDK8/19 inhibitors in the clinical pipeline.
Assuntos
Quinases Ciclina-Dependentes , Inibidores de Proteínas Quinases , Quinases Ciclina-Dependentes/metabolismo , Desenho de Fármacos , Humanos , Fosforilação , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêuticoRESUMO
Rice (Oryza sativa L.) is one of the most important staple foods consumed in many countries of the world. It is mostly consumed in developing countries where different chemical fertilizers are used to improve the productivity of the crop plant. In the present study, endophytic actinomycetes isolated from Rumex dentatus were identified morphologically and by scanning electron microscopy. Butyl isobutyl phthalate (BIBP) was isolated from the root endophyte Streptomyces sp. JR9 using column chromatography and HPLC methods. The compound was tested for its effect on rice seed germination. BIBP, extracts, and isolates were evaluated for their plant growth effect on rice in a growth chamber. Isolates were also screened in vitro for phosphate solubilization activity and enzyme production. Indole-3-acetic acid (IAA) and BIBP produced in extracts were quantified and detected using high performance liquid chromatography (HPLC) and liquid chromatography-mass spectrometry (LC-MS) methods, respectively. BIBP was found to increase the germination of rice seeds by 6 to 12% in treated samples and displayed potent effect at lowest concentration (0.437 µM). Both the compound and the extract depicted significant increases in almost all growth parameters at lowest concentration of 0.125 µg/mL and 62.5 µg/mL, respectively. BIBP also increased significantly shoot length, fresh root, fresh shoot, and dried shoot weight at high concentrations and was more potent than the standard phytohormone IAA. HPLC quantification showed 7.952 µg/mg and 0.371 µg/mg of IAA in extracts of Streptomyces sp. JR9 and the stem endophyte Streptomyces sp. KS3, respectively. IAA containing extract of JR9 increased significantly most growth parameters at lowest concentration (125 µg/mL). The extract of KS3 depicted significant increases in almost all growth parameters at high concentration (500 µg/mL). Our investigation showed that streptomycetes isolated from R. dentatus and BIBP are potent growth promoting agents and can be used in agriculture as bio-fertilizer to improve the growth and productivity of rice. KEY POINTS: ⢠Butyl isobutyl phthalate (BIBP) isolated from endophytic Streptomyces sp. JR9 is a potent rice seed germination activator and promotes significantly the growth of rice ⢠Isolated endophytes showed the ability to produce enzymes and phytohormone IAA ⢠Isolates enhanced significantly the growth of rice.
Assuntos
Oryza , Rumex , Streptomyces , Endófitos , Ácidos Ftálicos , Extratos Vegetais , Reguladores de Crescimento de PlantasRESUMO
Rumex abyssinicus Jacq. is a perennial medicinal herb widely used in traditional medicine to treat many diseases. Phytochemicals of the plant were isolated using column chromatography and thin layer chromatography techniques. Extract, fractions and pure compounds were screened for antimicrobial activity against sensitive and multi-drug resistant microbes and their cytotoxicity was performed on different cancer cell lines. The mechanism of action of purified helminthosporin as well as the potent fraction containing a mixture of two compounds was assessed. Fraction R7C3 was the most potent antibacterial with the lowest MIC value of 0.12 µg/mL. Helminthosporin was the most potent compound with the lowest MIC value of 1.95 µg/mL. The compound was more potent than the antibiotic chloramphenicol against multi-drug resistant (MDR) bacteria with MIC equal to 16 µg/mL. The fraction and helminthosporin were shown to destroy the cell wall of the yeast and bacteria, and DNA fragmentation effect on the genome of Candida albicans and Bacillus cereus. Helminthosporin was the most cytotoxic compound with IC50 Ë 10 µM. Fraction R7C3 showed the most potent cytotoxic effects on all cancer cell lines, with IC50 ranging from Ë1 to 4.35 ng/mL. Our study is the first report on the mechanism of action of helminthosporin, a potent candidate in the development of new drugs against multi-resistant bacteria and cancer cells. In addition, this study uncovered Rumex abyssinicus as a new source of syringic acid and bis(2-ethyloctyl) phthalate.
Assuntos
Anti-Infecciosos , Antineoplásicos , Rumex , Anti-Infecciosos/farmacologia , AntibacterianosRESUMO
Alzheimer's disease (AD) is a multifaceted neurodegenerative disorder involving various pathological events. The existing options for managing the disease utterly rely on cholinesterase (ChE) inhibitors. In recent years, the dual inhibition of ChEs as a potential AD therapeutics has substantially attracted the attention of medicinal chemists. Recently, we reported benzyl piperidinyl-linked methoxy-naphthamides as dual ChE inhibitors. Herein, we investigated the peripheral anionic binding site-binding methoxy-naphthamide fragment that yielded benzyl piperidinyl-linked benzyl aminobenzamide as another class of dual ChE inhibitors. The 3,5-dimethoxy benzyl aminobenzamide, 8c1, exhibits inhibition of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) with half-maximal inhibitory concentration values of 0.61 and 2.04 µM, respectively. The enzyme kinetics and molecular modeling study indicated the noncompetitive and mixed-type mode of inhibition for AChE and BChE with ki values of 0.14 and 0.46 µM, respectively. The derivative 8c1 crosses the blood-brain barrier as indicated by the Pe value of 14.34 × 10-6 cm/s in the parallel artificial membrane permeability assay. Besides this, it also inhibits the self-aggregation of amyloid-ß. The results presented herein indicate the potential of benzamide 8c1 for further investigation in preclinical models of AD.
Assuntos
Doença de Alzheimer , Inibidores da Colinesterase , Humanos , Inibidores da Colinesterase/farmacologia , Inibidores da Colinesterase/química , Butirilcolinesterase/metabolismo , Acetilcolinesterase/metabolismo , Barreira Hematoencefálica/metabolismo , Simulação de Acoplamento Molecular , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Relação Estrutura-AtividadeRESUMO
Natural products have significantly contributed to drug discovery for neurodegenerative diseases. Caffeine is one of the well-known central nervous system(CNS)-active natural products. Besides its CNS stimulant properties, it is a mild inhibitor of acetylcholinesterase (AChE) and possesses memory-enhancing properties. The present work aimed to improve the AChE inhibition activity of the caffeine. The rationally designed caffeine-based triazoles were synthesized and evaluated in vitro for cholinesterase and ß-site amyloid precursor protein cleaving enzyme-1 (BACE-1) inhibitory activities. The attachment of triazole to the caffeine enhances its AChE inhibition activity from half-maximal inhibitory concentration (IC50 ) of 129 µM to 0.49 µM (derivative, 6l). The caffeine core interacts with the peripheral anionic site, whereas the benzyl triazole occupies the catalytic anionic site located at the bottom of the active site gorge. The structure-activity relationship revealed that the four-atom ester linker is superior to shorter linkers for connecting the caffeine core to the triazole. The 2,6-difluorobenzyl triazole-linked caffeine derivative, 6d, exhibits dual inhibition of AChE and BACE-1 with IC50 values of 1.43 and 10.9 µM, respectively. The derivative 6d inhibits AChE via a mixed-type mode with an inhibition rate constant (Ki ) value of 2.35 µM, which was corroborated by docking studies. The triazole 6d has an acceptable stability profile in human liver microsomes (t1/2 = 54 min) and was found to possess CNS permeability when evaluated using the parallel artificial membrane permeability blood-brain barrier assay. The results presented herein warrant investigating caffeine-based triazoles in preclinical models of Alzheimer's disease.
Assuntos
Doença de Alzheimer , Produtos Biológicos , Humanos , Acetilcolinesterase/metabolismo , Cafeína/farmacologia , Inibidores da Colinesterase/química , Triazóis/farmacologia , Estrutura Molecular , Relação Estrutura-Atividade , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Simulação de Acoplamento MolecularRESUMO
Rohitukine, a chromone alkaloid extracted from Dysoxylum binectariferum, has a propitious anticancer activity. Our previous study shows that a new Rohitukine derivative IIIM-290 restricts the growth of pancreatic cancer in vivo and in vitro. In the present findings, we report the mechanism of cell death induced by IIIM-290 in MOLT-4 cells (acute lymphoblastic leukemia) and its anticancer potential against various murine leukemic tumor models in vivo. We found that IIIM-290 induced apoptosis through upregulation of different apoptotic proteins like PUMA, BAX, cytochrome c, cleaved (active) caspase-3, and cleaved PARP in MOLT-4 cells. Moreover, IIIM-290 abated mitochondrial membrane potential, elevated calcium levels, reactive oxygen species, and arrested growth of MOLT-4 cells in the synthesis (S) phase of the cell cycle. Interestingly, the elevation in proapoptotic markers was p53 dependent-the silencing of p53 abrogated apoptosis (programmed cell death) triggered by IIIM-290 in MOLT-4 cells. Furthermore, IIIM-290 significantly enhanced the survival of animals with P388 and L1210 leukemia. Thus, our results put IIIM-290 as a potential candidate for the anticancer lead.
Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Cromonas/farmacologia , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Piperidinas/farmacologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Animais , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Linhagem Celular Tumoral , Cromonas/química , Modelos Animais de Doenças , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , Piperidinas/química , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Proteína Supressora de Tumor p53/metabolismo , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
NLRP3 inflammasome is involved in several chronic inflammatory diseases. The inflammatory effect of the NLRP3 inflammasome is executed through IL-1ß and IL-18. Therefore, IL-1ß is one of the primary targets in chronic inflammatory conditions. However, current treatment regimens are dependent on anti- IL-1ß biologicals. The therapies targeting IL-1ß through inhibition of NLRP3 inflammasome are thus being actively explored. We identified safranal, a small molecule responsible for the essence of saffron as a potential inhibitor of the NLRP3 inflammasome. Safranal significantly suppressed the release of IL-1ß from ATP stimulated J774A.1 and bone marrow-derived macrophages (BMDMs) by regulating CASP1 and CASP8 dependent cleavage of pro-IL-1ß. Safranal markedly suppressed the expression of NLRP3 and its ATPase activity. Safranal treatment enhanced the expression of NRF2, whereas, si-RNA mediated silencing of Nrf2 abrogated the anti-NLRP3 effect of safranal. Furthermore, safranal inhibited ASC oligomerization and formation of ASC specks. Safranal also displayed anti-NLRP3 activity in multiple mice models. Treatment of animals with safranal reduced the production of IL-1ß in ATP elicited peritoneal inflammation, MSU induced air pouch inflammation, and MSU injected foot paw edema in mice. Thus, our data projects safranal as a potential preclinical drug candidate against NLRP3 inflammasome triggered chronic inflammation.
Assuntos
Proteínas Adaptadoras de Sinalização CARD/antagonistas & inibidores , Proteínas Adaptadoras de Sinalização CARD/metabolismo , Cicloexenos/farmacologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/antagonistas & inibidores , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Terpenos/farmacologia , Animais , Linhagem Celular , Células Cultivadas , Cicloexenos/uso terapêutico , Relação Dose-Resposta a Droga , Feminino , Humanos , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Terpenos/uso terapêuticoRESUMO
Aplysinopsins are a group of marine-derived indole alkaloids that display diverse array of pharmacological effects. However, their effect on anti-Alzheimer targets has not been reported. Herein, we report the synthesis of aplysinopsin (1) and its effect on cholinesterases and beta-site amyloid-precursor protein cleaving enzyme 1 (BACE-1). It inhibits electric eel acetylcholinesterase (AChE), equine serum butyrylcholinesterase (BChE), and human BACE-1 with IC50 values of 33.9, 30.3, and 33.7 µM, respectively, and excellent BBB permeability (Pe 8.92 × 10-6 cm/s). To optimize its sub-micromolar activity, the first-generation analogs were prepared and screened. Two most active analogs 5b and (Z)-8g were found to effectively permeate the BBB (Pe > 5 × 10-6 cm/s). The N-sulphonamide derivative 5b display better cholinesterase inhibition, whereas the other analog (Z)-8g strongly inhibits BACE-1 (IC50 0.78 µM) activity. The analog 5b interacts primarily with PAS of AChE, and thus exhibit a mixed-type of inhibition. In addition, aplysinopsin along with new analogs inhibited the self-induced Aß1-42 aggregation. The data presented herein indicate that the aplysinopsin-scaffold holds a potential for further investigation as a multi-targeted anti-Alzheimer agent.
Assuntos
Acetilcolinesterase/química , Secretases da Proteína Precursora do Amiloide/antagonistas & inibidores , Ácido Aspártico Endopeptidases/antagonistas & inibidores , Barreira Hematoencefálica/efeitos dos fármacos , Butirilcolinesterase/química , Inibidores da Colinesterase/farmacologia , Triptofano/análogos & derivados , Acetilcolinesterase/metabolismo , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/patologia , Secretases da Proteína Precursora do Amiloide/metabolismo , Peptídeos beta-Amiloides/metabolismo , Ácido Aspártico Endopeptidases/metabolismo , Sítios de Ligação , Barreira Hematoencefálica/metabolismo , Butirilcolinesterase/metabolismo , Inibidores da Colinesterase/química , Inibidores da Colinesterase/metabolismo , Humanos , Cinética , Simulação de Acoplamento Molecular , Fragmentos de Peptídeos/metabolismo , Agregados Proteicos/efeitos dos fármacos , Relação Estrutura-Atividade , Triptofano/química , Triptofano/metabolismo , Triptofano/uso terapêuticoRESUMO
The structure-guided virtual screening (VS) has proved to be successful strategy in identification of new scaffolds for biological targets. The overactivity of NLRP3 inflammasome has been implicated in variety of inflammatory diseases including Alzheimer's disease. The up-regulation of estrogen-receptor ß (ER-ß) activity has been directly linked with inhibition of NLRP3 inflammasome activity. In the present study, we report discovery of new NLRP3 inflammasome inhibitors via ER-ß crystal structure (PDB: 5TOA) guided virtual screening of 20,000 compound library. For experimental validation, top 10 ligands were selected based on structure novelty, docking score, prime MMGB/SA binding affinity and interaction pattern analysis. Amongst the tested compounds, three thiazolidin-4-ones IIIM-1268, IIIM-1269 and IIIM-1270 and benzo[cd]indol-2-one IIIM-1266 have shown 73, 69, 75 and 77% suppression of IL-1ß release in mouse macrophages (J774A.1 cells) at 10 µM. Benzylidene-thiazolidine-2,4-diones IIIM-1268 and IIIM-1270 inhibited IL-1ß release with IC50 of 2.3 and 3.5 µM and also significantly decreased the protein expression level of mature form of IL-1ß in western-blot analysis. IIIM-1266 and IIIM-1270 displayed bidentate H-bonding with Arg 346 and Glu 305 residues in the active site of ER-ß; and they also strongly occupied the ADP-binding site of NLRP3 protein. The results presented herein, indicate that ER-ß guided VS can be successfully used to identify new NLRP3 inflammasome inhibitors, which may have potential in the development of novel anti-Alzheimer agents.
Assuntos
Compostos de Benzilideno/farmacologia , Descoberta de Drogas , Receptor beta de Estrogênio/antagonistas & inibidores , Inflamassomos/efeitos dos fármacos , Proteína 3 que Contém Domínio de Pirina da Família NLR/antagonistas & inibidores , Tiazolidinedionas/farmacologia , Animais , Compostos de Benzilideno/síntese química , Compostos de Benzilideno/química , Linhagem Celular , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Receptor beta de Estrogênio/metabolismo , Inflamassomos/metabolismo , Camundongos , Estrutura Molecular , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Relação Estrutura-Atividade , Tiazolidinedionas/síntese química , Tiazolidinedionas/químicaRESUMO
NLRP3 inflammasome is an important therapeutic target for a number of human diseases. Herein, computationally designed series of quinazolin-4(3 H)-ones were synthesized using iodine-catalyzed coupling of arylalkynes (or styrenes) with O-aminobenzamides. The key event in this transformation involves the oxidative cleavage of the C-C triple/double bond and the release of formaldehyde. The reaction relies on the C-N bond formation along with the C-C bond cleavage under metal-free conditions. The nitro-substituted quinazolin-4(3 H)-one 2k inhibited NLRP3 inflammasome (IC50 5 µM) via the suppression of IL-1ß release from ATP-stimulated J774A.1 cells.
Assuntos
Desenho de Fármacos , Inflamassomos/antagonistas & inibidores , Proteína 3 que Contém Domínio de Pirina da Família NLR/antagonistas & inibidores , Quinazolinas/síntese química , Quinazolinas/farmacologia , Técnicas de Química Sintética , Inflamassomos/química , Modelos Moleculares , Proteína 3 que Contém Domínio de Pirina da Família NLR/química , Conformação Proteica , Quinazolinas/químicaRESUMO
Herein, we have identified yeast Sec22p (ySec22p), a SNARE protein essential for endoplasmic reticulum to Golgi trafficking, as a suppressor of Bax-induced yeast apoptosis and corroborated published observations that ySec22p suppresses α-synuclein's toxicity in yeast. It has been suggested that compounds which enhance expression, in neurons, of human homologues of ySec22p (Sec22Bp/Sec22p/Sec22A) would prevent synucleinopathies, such as Parkinson's disease. With the aim of finding a small molecule that would mimic ySec22p, a library of natural products consisting of 394-compounds was screened using yeast cells that express either human α-synuclein or human Bax. The antioxidant aegeline, an alkaloid-amide occurring in the leaves of the plant Aegle marmelos Correa, was the only molecule that overcame apoptosis induced by both α-synuclein and Bax in yeast. Besides, aegeline also prevented growth block in cells expressing the more toxic A53T α-synuclein mutant. Restoration of cell growth occurred through inhibition of increased ROS levels, mitochondrial membrane potential loss and nuclear DNA fragmentation, characteristics of apoptosis manifested in α-synuclein or Bax-expressing cells. These results highlight the importance of yeast systems to identify rapidly molecules that may prevent the onset of apoptosis that occurs in Parkinson's disease.
Assuntos
Aegle/química , Amidas/farmacologia , Antioxidantes/farmacologia , Produtos Biológicos/farmacologia , Proteínas R-SNARE/antagonistas & inibidores , Proteínas de Saccharomyces cerevisiae/antagonistas & inibidores , Saccharomyces cerevisiae/efeitos dos fármacos , Amidas/química , Amidas/isolamento & purificação , Antioxidantes/química , Antioxidantes/isolamento & purificação , Apoptose/efeitos dos fármacos , Produtos Biológicos/química , Produtos Biológicos/isolamento & purificação , Relação Dose-Resposta a Droga , Estrutura Molecular , Proteínas R-SNARE/metabolismo , Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/citologia , Proteínas de Saccharomyces cerevisiae/metabolismo , Relação Estrutura-Atividade , alfa-Sinucleína/metabolismo , Proteína X Associada a bcl-2/metabolismoRESUMO
Alkaloids have always been a great source of cholinesterase inhibitors. Numerous studies have shown that inhibiting acetylcholinesterase as well as butyrylcholinetserase is advantageous, and have better chances of success in preclinical/ clinical settings. With the objective to discover dual cholinesterase inhibitors, herein we report synthesis and biological evaluation of indoloquinoline alkaloid cryptolepine (1) and its bromo-derivative 2. Our study has shown that cryptolepine (1) and its 2-bromo-derivative 2 are dual inhibitors of acetylcholinesterase and butyrylcholinesterase, the enzymes which are involved in blocking the process of neurotransmission. Cryptolepine inhibits Electrophorus electricus acetylcholinesterase, recombinant human acetylcholinesterase and equine serum butyrylcholinesterase with IC50 values of 267, 485 and 699â¯nM, respectively. The 2-bromo-derivative of cryptolepine also showed inhibition of these enzymes, with IC50 values of 415, 868 and 770â¯nM, respectively. The kinetic studies revealed that cryptolepine inhibits human acetylcholinesterase in a non-competitive manner, with ki value of 0.88⯵M. Additionally, these alkaloids were also tested against two other important pathological events of Alzheimer's disease viz. stopping the formation of toxic amyloid-ß oligomers (via inhibition of BACE-1), and increasing the amyloid-ß clearance (via P-gp induction). Cryptolepine displayed potent P-gp induction activity at 100â¯nM, in P-gp overexpressing adenocarcinoma LS-180 cells and excellent toxicity window in LS-180 as well as in human neuroblastoma SH-SY5Y cell line. The molecular modeling studies with AChE and BChE have shown that both alkaloids were tightly packed inside the active site gorge (site 1) via multiple π-π and cation-π interactions. Both inhibitors have shown interaction with the allosteric "peripheral anionic site" via hydrophobic interactions. The ADME properties including the BBB permeability were computed for these alkaloids, and were found within the acceptable range.
Assuntos
Acetilcolinesterase/química , Antimaláricos/farmacologia , Butirilcolinesterase/química , Inibidores da Colinesterase/síntese química , Inibidores da Colinesterase/farmacologia , Alcaloides Indólicos/síntese química , Alcaloides Indólicos/farmacologia , Indóis/síntese química , Indóis/farmacologia , Quinolinas/síntese química , Quinolinas/farmacologia , Antimaláricos/síntese química , Proliferação de Células , Humanos , Modelos Moleculares , Simulação de Acoplamento Molecular , Estrutura Molecular , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Conformação Proteica , Relação Estrutura-Atividade , Células Tumorais CultivadasRESUMO
Aggregation/misfolding of α-synuclein and ßA4 proteins cause neuronal cell death (NCD) associated with Parkinson's and Alzheimer's disease. It has been suggested that a heat shock protein-90 (Hsp90) inhibitor can prevent NCD by activating the heat shock transcription factor-1 which, in turn, upregulates molecular chaperones such as Hsp70 that targets aggregated/misfolded proteins for refolding/degradation. We have isolated radicicol, an Hsp90 inhibitor, from a fungus occurring in the crevices of marble rocks of Central India. Radicicol, which was found to be a strong antioxidant, was tested for its ability to rescue yeast cells from death induced by expression of wild-type α-synuclein, its more toxic A53T mutant, and ßA4. It effectively overcomes wild-type/mutant α-synuclein mediated yeast cell death, concomitantly diminishes ROS levels, reverses mitochondrial dysfunction and prevents nuclear DNA-fragmentation, a hallmark of apoptosis. Surprisingly however, radicicol is unable to rescue yeast cells from death triggered by expression of secreted ßA4. Moreover, although radicicol acts as an antioxidant it fails to prevent yeast cell death inflicted by the proapoptotic protein, Bax. Our results indicate that radicicol specifically targets aggregated/misfolded α-synuclein's toxicity and opens up the possibility of using multiple yeast assays to screen natural product libraries for compounds that would unambiguously target α-synuclein aggregation/misfolding.
Assuntos
Peptídeos beta-Amiloides/metabolismo , Apoptose/efeitos dos fármacos , Sequestradores de Radicais Livres/farmacologia , Macrolídeos/farmacologia , alfa-Sinucleína/metabolismo , Proteína X Associada a bcl-2/metabolismo , Peptídeos beta-Amiloides/genética , Sequestradores de Radicais Livres/isolamento & purificação , Sequestradores de Radicais Livres/metabolismo , Humanos , Macrolídeos/isolamento & purificação , Macrolídeos/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/metabolismo , Simulação de Acoplamento Molecular , Mutação , Ligação Proteica , Espécies Reativas de Oxigênio/metabolismo , Saccharomyces cerevisiae/genética , Sordariales/química , alfa-Sinucleína/genética , Proteína X Associada a bcl-2/genéticaRESUMO
Beta-secreatse (BACE-1) and cholinesterases are clinically validated targets of Alzheimer's disease (AD), for which natural products have provided immense contribution. The multifaceted nature of AD signifies the need of multitargeted agents to tackle this disease. In the search of new natural products as dual BACE-1/cholinesterase inhibitors, a library of pure natural products was screened for inhibition of acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and BACE-1. The screening efforts have identified 1,4-benzoquinone "embelin," a natural product derived from Embelia ribes displaying inhibition of all three enzymes, with IC50 values of 2.5, 5.4, and 2.1 µM, respectively. This screen has also identified isoquinoline alkaloids papaverine and L-tetrahydropalmatine as AChE inhibitors. Kinetic study has shown that embelin inhibits EeAChE and EqBChE with ki values of 4.59 and 0.57 µM, in an uncompetitive and noncompetitive manner, respectively. The interactions of embelin with allosteric peripheral anionic site of cholinesterases, has further supported the results of kinetic study. Embelin has also enhanced the activity of P-gp in LS-180 cells, the efflux pump which is involved in the clearance of amyloid-ß from AD brain. Further, the cell viability study in neuronal cell line has indicated the excellent therapeutic window of embelin. These results are indicative of the fact that embelin is a multitargeted agent playing role in stopping the formation of amyloid-ß oligomers (via inhibition of BACE-1), improves cholinergic-transmission (via inhibition of AChE/BChE) and increases amyloid-ß clearance (via P-gp induction).
Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/química , Acetilcolinesterase/química , Doença de Alzheimer/metabolismo , Secretases da Proteína Precursora do Amiloide/química , Ácido Aspártico Endopeptidases/química , Benzoquinonas/farmacologia , Butirilcolinesterase/química , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/antagonistas & inibidores , Doença de Alzheimer/tratamento farmacológico , Secretases da Proteína Precursora do Amiloide/antagonistas & inibidores , Ácido Aspártico Endopeptidases/antagonistas & inibidores , Benzoquinonas/química , Butirilcolinesterase/metabolismo , Linhagem Celular , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Embelia/química , Proteínas Ligadas por GPI/antagonistas & inibidores , Proteínas Ligadas por GPI/química , Humanos , Modelos Moleculares , Simulação de Acoplamento Molecular , Estrutura MolecularRESUMO
Expression of cytochrome P450-1A1 (CYP1A1) is suppressed under physiologic conditions but is induced (a) by polycyclic aromatic hydrocarbons (PAHs) which can be metabolized by CYP1A1 to carcinogens, and (b) in majority of breast cancers. Hence, phytochemicals or dietary flavonoids, if identified as CYP1A1 inhibitors, may help in preventing PAH-mediated carcinogenesis and breast cancer. Herein, we have investigated the cancer chemopreventive potential of a flavonoid-rich Indian medicinal plant, Pongamia pinnata (L.) Pierre. Methanolic extract of its seeds inhibits CYP1A1 in CYP1A1-overexpressing normal human HEK293 cells, with IC50 of 0.6⯵g/mL. Its secondary metabolites, the furanoflavonoids pongapin/lanceolatin B, inhibit CYP1A1 with IC50 of 20â¯nM. Although the furanochalcone pongamol inhibits CYP1A1 with IC50 of only 4.4⯵M, a semisynthetic pyrazole-derivative P5b, has â¼10-fold improved potency (IC50, 0.49⯵M). Pongapin/lanceolatin B and the methanolic extract of P. pinnata seeds protect CYP1A1-overexpressing HEK293 cells from B[a]P-mediated toxicity. Remarkably, they also block the cell cycle of CYP1A1-overexpressing MCF-7 breast cancer cells, at the G0-G1 phase, repress cyclin D1 levels and induce cellular-senescence. Molecular modeling studies demonstrate the interaction pattern of pongapin/lanceolatin B with CYP1A1. The results strongly indicate the potential of methanolic seed-extract and pongapin/lanceolatin B for further development as cancer chemopreventive agents.
Assuntos
Antineoplásicos/farmacologia , Benzopiranos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Citocromo P-450 CYP1A1/antagonistas & inibidores , Flavonas/farmacologia , Furanos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Benzopiranos/síntese química , Benzopiranos/química , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Senescência Celular/efeitos dos fármacos , Citocromo P-450 CYP1A1/biossíntese , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Flavonas/síntese química , Flavonas/química , Citometria de Fluxo , Furanos/síntese química , Furanos/química , Células HEK293 , Humanos , Células MCF-7 , Modelos Moleculares , Estrutura Molecular , Relação Estrutura-AtividadeRESUMO
Oxidant controlled ionic liquid mediated cross-dehydrogenative coupling (CDC) of benzylamines with N-heterocycles having sp2 or sp3 carbon resulted in the formation of C-benzoylated or alkenylated products. Benzoylation of N-heterocycles occurs via (NH4)2S2O8 catalyzed benzoyl radical formation. An oxidative alkenylation of N-heterocycles having C-sp3 carbon (2-methylaza-arenes) occurs via deamination of benzylamine followed by C-sp3-H bond activation in high stereoselectivity. Both benzoylation and alkenylation protocols are metal-free, green, simple, efficient, and tolerate a wide variety of functional groups.