Your browser doesn't support javascript.
loading
Montrer: 20 | 50 | 100
Résultats 1 - 20 de 946
Filtrer
1.
Molecules ; 29(8)2024 Apr 13.
Article de Anglais | MEDLINE | ID: mdl-38675599

RÉSUMÉ

We introduced a terminal alkyne into the core structure of dolutegravir, resulting in the synthesis of 34 novel dolutegravir-1,2,3-triazole compounds through click chemistry. These compounds exhibited remarkable inhibitory activities against two hepatocellular carcinoma cell lines, Huh7 and HepG2. Notably, compounds 5e and 5p demonstrated exceptional efficacy, particularly against Huh7 cells, with IC50 values of 2.64 and 5.42 µM. Additionally, both compounds induced apoptosis in Huh7 cells, suppressed tumor cell clone formation, and elevated reactive oxygen species (ROS) levels, further promoting tumor cell apoptosis. Furthermore, compounds 5e and 5p activated the LC3 signaling pathway, inducing autophagy, and triggered the γ-H2AX signaling pathway, resulting in DNA damage in tumor cells. Compound 5e exhibited low toxicity, highlighting its potential as a promising anti-tumor drug.


Sujet(s)
Antinéoplasiques , Apoptose , Autophagie , Altération de l'ADN , Composés hétérocycliques 3 noyaux , Tumeurs du foie , Oxazines , Pipérazines , Pyridones , Espèces réactives de l'oxygène , Humains , Pyridones/pharmacologie , Pyridones/composition chimique , Autophagie/effets des médicaments et des substances chimiques , Altération de l'ADN/effets des médicaments et des substances chimiques , Tumeurs du foie/traitement médicamenteux , Tumeurs du foie/métabolisme , Tumeurs du foie/anatomopathologie , Pipérazines/pharmacologie , Pipérazines/composition chimique , Oxazines/pharmacologie , Oxazines/composition chimique , Composés hétérocycliques 3 noyaux/pharmacologie , Composés hétérocycliques 3 noyaux/composition chimique , Antinéoplasiques/pharmacologie , Antinéoplasiques/composition chimique , Apoptose/effets des médicaments et des substances chimiques , Lignée cellulaire tumorale , Espèces réactives de l'oxygène/métabolisme , Cellules HepG2 , Carcinome hépatocellulaire/traitement médicamenteux , Carcinome hépatocellulaire/métabolisme , Carcinome hépatocellulaire/anatomopathologie , Transduction du signal/effets des médicaments et des substances chimiques , Prolifération cellulaire/effets des médicaments et des substances chimiques , Découverte de médicament
2.
Chem Biodivers ; 20(12): e202301512, 2023 Dec.
Article de Anglais | MEDLINE | ID: mdl-37921566

RÉSUMÉ

Four new phomalones A-D (1-4), together with five known analogues (5-9) were isolated from the deep-sea-derived fungus Trichobotrys effuse FS522. Their structures of the new compounds established by analysis of their NMR and HR-ESI-MS spectroscopic data, and the absolute configurations of 2 was determined by electronic circular dichroism (ECD) calculations. compounds 4, 6 and 8 substantially inhibited the production of nitric oxide (NO) with IC50 values of 4.64, 13.90, and 34.07 µM.


Sujet(s)
Ascomycota , Anti-inflammatoires/pharmacologie , Spectroscopie par résonance magnétique/méthodes , Structure moléculaire , Pyrannes/composition chimique , Pyrannes/pharmacologie , Composés hétérocycliques 3 noyaux/composition chimique , Composés hétérocycliques 3 noyaux/pharmacologie
3.
J Chem Inf Model ; 62(7): 1712-1722, 2022 04 11.
Article de Anglais | MEDLINE | ID: mdl-35192364

RÉSUMÉ

Parasitic weeds such as Striga have led to significant losses in agricultural productivity worldwide. These weeds use the plant hormone strigolactone as a germination stimulant. Strigolactone signaling involves substrate hydrolysis followed by a conformational change of the receptor to a "closed" or "active" state that associates with a signaling partner, MAX2/D3. Crystal structures of active and inactive AtD14 receptors have helped elucidate the structural changes involved in activation. However, the mechanism by which the receptor activates remains unknown. The ligand dependence of AtD14 activation has been disputed by mutagenesis studies showing that enzymatically inactive receptors are able to associate with MAX2 proteins. Furthermore, activation differences between strigolactone receptor in Striga, ShHTL7, and AtD14 could contribute to the high sensitivity to strigolactones exhibited by parasitic plants. Using molecular dynamics simulations, we demonstrate that both AtD14 and ShHTL7 could adopt an active conformation in the absence of ligand. However, ShHTL7 exhibits a higher population in the inactive apo state as compared to the AtD14 receptor. We demonstrate that this difference in inactive state population is caused by sequence differences between their D-loops and interactions with the catalytic histidine that prevent full binding pocket closure in ShHTL7. These results indicate that ligand hydrolysis would enhance the active state population by destabilizing the inactive state in ShHTL7 as compared to AtD14. We also show that the mechanism of activation is more concerted in AtD14 than in ShHTL7 and that the main barrier to activation in ShHTL7 is closing of the binding pocket.


Sujet(s)
Striga , Protéines de transport/métabolisme , Composés hétérocycliques 3 noyaux/composition chimique , Composés hétérocycliques 3 noyaux/métabolisme , Lactones/composition chimique , Lactones/métabolisme , Lactones/pharmacologie , Ligands , Mauvaises herbes/composition chimique , Mauvaises herbes/métabolisme , Striga/composition chimique , Striga/métabolisme
4.
J Med Chem ; 65(3): 2238-2261, 2022 02 10.
Article de Anglais | MEDLINE | ID: mdl-35104137

RÉSUMÉ

A series of latonduine and indoloquinoline derivatives HL1-HL8 and their copper(II) complexes (1-8) were synthesized and comprehensively characterized. The structures of five compounds (HL6, [CuCl(L1)(DMF)]·DMF, [CuCl(L2)(CH3OH)], [CuCl(L3)]·0.5H2O, and [CuCl2(H2L5)]Cl·2DMF) were elucidated by single crystal X-ray diffraction. The copper(II) complexes revealed low micro- to sub-micromolar IC50 values with promising selectivity toward human colon adenocarcinoma multidrug-resistant Colo320 cancer cells as compared to the doxorubicin-sensitive Colo205 cell line. The lead compounds HL4 and 4 as well as HL8 and 8 induced apoptosis efficiently in Colo320 cells. In addition, the copper(II) complexes had higher affinity to DNA than their metal-free ligands. HL8 showed selective inhibition for the PIM-1 enzyme, while 8 revealed strong inhibition of five other enzymes, i.e., SGK-1, PKA, CaMK-1, GSK3ß, and MSK1, from a panel of 50 kinases. Furthermore, molecular modeling of the ligands and complexes showed a good fit to the binding pockets of these targets.


Sujet(s)
Complexes de coordination/composition chimique , Cuivre/composition chimique , Composés hétérocycliques 3 noyaux/composition chimique , Inhibiteurs de protéines kinases/composition chimique , Quinoléines/composition chimique , Animaux , Antinéoplasiques/composition chimique , Antinéoplasiques/métabolisme , Antinéoplasiques/pharmacologie , Antinéoplasiques/usage thérapeutique , Sites de fixation , Bovins , Lignée cellulaire tumorale , Prolifération cellulaire/effets des médicaments et des substances chimiques , Complexes de coordination/métabolisme , Complexes de coordination/pharmacologie , Complexes de coordination/usage thérapeutique , Cristallographie aux rayons X , ADN/composition chimique , ADN/métabolisme , Humains , Indoles/composition chimique , Conformation moléculaire , Simulation de docking moléculaire , Inhibiteurs de protéines kinases/métabolisme , Inhibiteurs de protéines kinases/pharmacologie , Inhibiteurs de protéines kinases/usage thérapeutique , Protein kinases/composition chimique , Protein kinases/métabolisme , Solubilité , Relation structure-activité
5.
Inorg Chem ; 61(3): 1456-1470, 2022 Jan 24.
Article de Anglais | MEDLINE | ID: mdl-34995063

RÉSUMÉ

Indolo[2,3-d]benzazepines (indololatonduines) are rarely discussed in the literature. In this project, we prepared a series of novel indololatonduine derivatives and their RuII and OsII complexes and investigated their microtubule-targeting properties in comparison with paclitaxel and colchicine. Compounds were fully characterized by spectroscopic techniques (1H NMR and UV-vis), ESI mass-spectrometry, and X-ray crystallography, and their purity was confirmed by elemental analysis. The stabilities of the compounds in DMSO and water were confirmed by 1H and 13C NMR and UV-vis spectroscopy. Novel indololatonduines demonstrated anticancer activity in vitro in a low micromolar concentration range, while their coordination to metal centers resulted in a decrease of cytotoxicity. The preliminary in vivo activity of the RuII complex was investigated. Fluorescence staining and in vitro tubulin polymerization assays revealed the prepared compounds to have excellent microtubule-destabilizing activities, even more potent than the well-known microtubule-destabilizing agent colchicine.


Sujet(s)
Antinéoplasiques/pharmacologie , Complexes de coordination/pharmacologie , Composés hétérocycliques 3 noyaux/pharmacologie , Indoles/pharmacologie , Microtubules/effets des médicaments et des substances chimiques , Animaux , Antinéoplasiques/synthèse chimique , Antinéoplasiques/composition chimique , Survie cellulaire/effets des médicaments et des substances chimiques , Complexes de coordination/synthèse chimique , Complexes de coordination/composition chimique , Cristallographie aux rayons X , Tests de criblage d'agents antitumoraux , Composés hétérocycliques 3 noyaux/composition chimique , Humains , Indoles/composition chimique , Tumeurs expérimentales de la mamelle/traitement médicamenteux , Tumeurs expérimentales de la mamelle/métabolisme , Tumeurs expérimentales de la mamelle/anatomopathologie , Souris , Souris nude , Microscopie de fluorescence , Microtubules/métabolisme , Modèles moléculaires , Structure moléculaire , Polymérisation/effets des médicaments et des substances chimiques , Tubuline/métabolisme , Cellules cancéreuses en culture
6.
Sci Rep ; 12(1): 1429, 2022 01 26.
Article de Anglais | MEDLINE | ID: mdl-35082341

RÉSUMÉ

The passive transport of glucose and related hexoses in human cells is facilitated by members of the glucose transporter family (GLUT, SLC2 gene family). GLUT3 is a high-affinity glucose transporter primarily responsible for glucose entry in neurons. Changes in its expression have been implicated in neurodegenerative diseases and cancer. GLUT3 inhibitors can provide new ways to probe the pathophysiological role of GLUT3 and tackle GLUT3-dependent cancers. Through in silico screening of an ~ 8 million compounds library against the inward- and outward-facing models of GLUT3, we selected ~ 200 ligand candidates. These were tested for in vivo inhibition of GLUT3 expressed in hexose transporter-deficient yeast cells, resulting in six new GLUT3 inhibitors. Examining their specificity for GLUT1-5 revealed that the most potent GLUT3 inhibitor (G3iA, IC50 ~ 7 µM) was most selective for GLUT3, inhibiting less strongly only GLUT2 (IC50 ~ 29 µM). None of the GLUT3 inhibitors affected GLUT5, three inhibited GLUT1 with equal or twofold lower potency, and four showed comparable or two- to fivefold better inhibition of GLUT4. G3iD was a pan-Class 1 GLUT inhibitor with the highest preference for GLUT4 (IC50 ~ 3.9 µM). Given the prevalence of GLUT1 and GLUT3 overexpression in many cancers and multiple myeloma's reliance on GLUT4, these GLUT3 inhibitors may discriminately hinder glucose entry into various cancer cells, promising novel therapeutic avenues in oncology.


Sujet(s)
Découverte de médicament , Transporteur de glucose de type 3/composition chimique , Composés hétérocycliques 3 noyaux/pharmacologie , Protéines de Saccharomyces cerevisiae/composition chimique , Saccharomyces cerevisiae/effets des médicaments et des substances chimiques , Bibliothèques de petites molécules/pharmacologie , Sites de fixation , Transport biologique/effets des médicaments et des substances chimiques , Lignée cellulaire tumorale , Survie cellulaire/effets des médicaments et des substances chimiques , Transporteur de glucose de type 1/antagonistes et inhibiteurs , Transporteur de glucose de type 1/composition chimique , Transporteur de glucose de type 1/génétique , Transporteur de glucose de type 1/métabolisme , Transporteur de glucose de type 2/antagonistes et inhibiteurs , Transporteur de glucose de type 2/composition chimique , Transporteur de glucose de type 2/génétique , Transporteur de glucose de type 2/métabolisme , Transporteur de glucose de type 3/antagonistes et inhibiteurs , Transporteur de glucose de type 3/génétique , Transporteur de glucose de type 3/métabolisme , Transporteur de glucose de type 4/antagonistes et inhibiteurs , Transporteur de glucose de type 4/composition chimique , Transporteur de glucose de type 4/génétique , Transporteur de glucose de type 4/métabolisme , Transporteur de glucose de type 5/antagonistes et inhibiteurs , Transporteur de glucose de type 5/composition chimique , Transporteur de glucose de type 5/génétique , Transporteur de glucose de type 5/métabolisme , Composés hétérocycliques 3 noyaux/composition chimique , Tests de criblage à haut débit , Humains , Modèles moléculaires , Tumeurs/traitement médicamenteux , Liaison aux protéines , Structure en hélice alpha , Structure en brin bêta , Motifs et domaines d'intéraction protéique , Saccharomyces cerevisiae/génétique , Saccharomyces cerevisiae/métabolisme , Protéines de Saccharomyces cerevisiae/antagonistes et inhibiteurs , Protéines de Saccharomyces cerevisiae/génétique , Protéines de Saccharomyces cerevisiae/métabolisme , Bibliothèques de petites molécules/composition chimique
7.
Article de Anglais | MEDLINE | ID: mdl-34875493

RÉSUMÉ

Upadacitinib, as a selective and reversible Janus kinase (JAK) inhibitor, has been widely used in the treatment of atopic dermatitis, ulcerative colitis and other inflammatory bowel diseases and other immune-mediated diseases. The combination of methotrexate and upadacitinib is a common clinical treatment strategy for rheumatoid arthritis (RA) in recent years. In this study, we established an ultra performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) assay for quantitative measurement of upadacitinib and methotrexate, by which we successfully determined pharmacokinetic parameters of them in rat plasma. In order to pretreat the samples, we used acetonitrile as the precipitant, and for the internal standard (IS), we chose tofacitinib. The Acquity BEHC18 (2.1 mm × 50 mm, 1.7 µm) column, with acetonitrile and 0.1% formic acid aqueous solution composed mobile phases, was used to separate upadacitinib, methotrexate and tofacitinib. A Xevo TQ-S triple quadrupole tandem mass spectrometer was used as the detecting instrument in the positive ion mode. For upadacitinib, excellent linearity was shown of this assay in the calibration range with 0.1-200 ng/mL, and as for methotrexate, the range was 0.05-100 ng/mL. As the results indicated, the lower limit of quantification (LLOQ) was respectively 0.1 and 0.05 ng/mL for upadacitinib and methotrexate, the intra- and inter-day precision were ≤ 13.3%, and the accuracy of all the analytes ranged from -4.1% to 12.7%. The recovery of each analyte was > 80.2% in this experiment, and matrix effects we observed were unobvious. The establishment of this method and its successful application in rat plasma can provide a theoretical and technical support for the deeper study of pharmacodynamics and the clinical medication strategies.


Sujet(s)
Chromatographie en phase liquide à haute performance/méthodes , Composés hétérocycliques 3 noyaux/sang , Méthotrexate/sang , Spectrométrie de masse en tandem/méthodes , Animaux , Composés hétérocycliques 3 noyaux/composition chimique , Composés hétérocycliques 3 noyaux/pharmacocinétique , Limite de détection , Modèles linéaires , Mâle , Méthotrexate/composition chimique , Méthotrexate/pharmacocinétique , Rats , Rat Sprague-Dawley , Reproductibilité des résultats
8.
J Ethnopharmacol ; 285: 114883, 2022 Mar 01.
Article de Anglais | MEDLINE | ID: mdl-34861363

RÉSUMÉ

ETHNOPHARMACOLOGICAL RELEVANCE: Medicinal plants have been used by the people of developing countries to treat various diseases. WHO also recommends the use of medicines from plants source. In that, diabetes also one of the diseases that have been treated traditionally by several people all over the world. In India, Toddalia asiatica (L.) Lam. (Rutaceae) is also a medicinal plant used traditionally for the treatment of diabetes in Ayurveda. Moreover, T. asiatica is also used in a polyherbal formulation to treat diabetes. AIM OF THE STUDY: This study examined the antidiabetic with antilipidemic and antioxidant effects of flindersine isolated from T. asiatica leaves. MATERIALS AND METHODS: Diabetes was induced in Wistar rats by feeding a high-fat diet (HFD) for 15 days and injecting a single dose of 40 mg/kg b. wt. of Streptozotocin (STZ). Five days post-injection, the grouped diabetic rats were treated with 20 and 40 mg/kg of flindersine. RESULTS: Flindersine resulted in a clear decline of blood glucose levels during 28 days of treatment in two different doses. Flindersine also significantly (P ≤ 0.05; P ≤ 0.005) reduced the body weight gain, plasma insulin concentration, urea, creatinine, total cholesterol (TC), triglycerides (TG) and free fatty acids (FFA) levels and significantly increased (P ≤ 0.05; P ≤ 0.005) the total protein level, superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) activities compared to the standard drug, pioglitazone. Additionally, flindersine restored the glucose transporter protein 4 (GLUT4), adenosine monophosphate protein kinase (AMPK) and peroxisome proliferator-activated receptor γ (PPARγ) expressions in adipose tissues and skeletal muscles. CONCLUSION: It has been found that flindersine has potent antilipidemic and antidiabetic activities by improving insulin sensitivity by enhancing the phosphorylation of AMPK, GLUT4 translocation, and PPARγ agonism on adipose tissue and skeletal muscles of diabetic rats.


Sujet(s)
Diabète de type 2/induit chimiquement , Diabète de type 2/traitement médicamenteux , Transporteur de glucose de type 4/métabolisme , Composés hétérocycliques 3 noyaux/pharmacologie , Hypoglycémiants/pharmacologie , Récepteur PPAR gamma/agonistes , Animaux , Antioxydants/composition chimique , Antioxydants/pharmacologie , Glycémie/effets des médicaments et des substances chimiques , Catalase , Diabète expérimental , Alimentation riche en graisse/effets indésirables , Relation dose-effet des médicaments , Régulation de l'expression des gènes/effets des médicaments et des substances chimiques , Glucose/métabolisme , Transporteur de glucose de type 4/génétique , Glutathione peroxidase , Composés hétérocycliques 3 noyaux/administration et posologie , Composés hétérocycliques 3 noyaux/composition chimique , Hypoglycémiants/composition chimique , Hypolipémiants/composition chimique , Hypolipémiants/pharmacologie , Mâle , Structure moléculaire , Récepteur PPAR gamma/génétique , Récepteur PPAR gamma/métabolisme , Phytothérapie , Extraits de plantes/composition chimique , Extraits de plantes/pharmacologie , Rats , Rat Wistar , Rutaceae/composition chimique , Superoxide dismutase
9.
J Mater Chem B ; 9(48): 9885-9892, 2021 12 15.
Article de Anglais | MEDLINE | ID: mdl-34821904

RÉSUMÉ

Fluorescent probes for the detection of intracellular nitric oxide (NO) are abundant, but those targeted to the mitochondria are scarce. Among those molecules targeting mitochondrial NO (mNO), the majority use a triphenylphosphonium (TPP) cation as a vector to reach such organelles. Here we describe a simple molecule (mtNOpy) based on the pyrylium structure, made in a few synthetic steps, capable of detecting selectively NO (aerated medium) over other reactive species. The calculated detection limit for mtNOpy is 88 nM. The main novelty of this probe is that it has a simple molecular architecture and can act both as a fluorogenic and as a mitochondriotropic agent, without using TPP. mtNOpy has been tested in two different scenarios: (a) in a controlled environment of cell line cultures (human colon carcinoma HT-29 cells and mouse macrophage RAW 264.7 cells), using confocal laser scanning microscopy, and (b) on a much more complex sample of peripheral blood, using flow cytometry. In the first context, mtNOpy has been found to be responsive (turn-on fluorescence) to exogenous and endogenous NO stimuli (via SNAP donor and LPS stimulation, respectively). In the second area, mtNOpy has been able to discriminate between NO-generating phagocytes (neutrophils and monocytes) from other leukocytes (NK, B and T cells).


Sujet(s)
Colorants fluorescents/composition chimique , Composés hétérocycliques 3 noyaux/composition chimique , Mitochondries/composition chimique , Monoxyde d'azote/analyse , Animaux , Cellules cultivées , Colorants fluorescents/synthèse chimique , Colorants fluorescents/métabolisme , Composés hétérocycliques 3 noyaux/sang , Composés hétérocycliques 3 noyaux/synthèse chimique , Humains , Lipopolysaccharides/pharmacologie , Test de matériaux , Souris , Microscopie confocale , Mitochondries/effets des médicaments et des substances chimiques , Mitochondries/métabolisme , Structure moléculaire , Monoxyde d'azote/métabolisme
10.
Org Lett ; 23(19): 7550-7554, 2021 10 01.
Article de Anglais | MEDLINE | ID: mdl-34543031

RÉSUMÉ

Here we describe the use of the hexadehydro-Diels-Alder (HDDA) reaction for the de novo construction of the isoindolinone scaffold and its application to the synthesis of the title natural products. The key isoindolinone-forming HDDA reaction involved an unprecedented substrate motif in which an amide carbonyl group was conjugated to the 4π 1,3-diyne component. In addition, a dimethylsilyl (-SiMe2H) substituent was exploited to trigger a Fleming-Tamao-Kumada oxidation for the installation of an essential phenolic hydroxyl group.


Sujet(s)
Composés hétérocycliques 3 noyaux/synthèse chimique , Indoles/synthèse chimique , Phtalimides/synthèse chimique , Produits biologiques , Réaction de cycloaddition , Composés hétérocycliques 3 noyaux/composition chimique , Indoles/composition chimique , Structure moléculaire , Oxydoréduction , Phtalimides/composition chimique
11.
Molecules ; 26(18)2021 Sep 09.
Article de Anglais | MEDLINE | ID: mdl-34576952

RÉSUMÉ

Several sesquiterpene lactones (STLs) have been tested as lead drugs in cancer clinical trials. Salograviolide-A (Sal-A) and salograviolide-B (Sal-B) are two STLs that have been isolated from Centaurea ainetensis, an indigenous medicinal plant of the Middle Eastern region. The parent compounds Sal-A and Sal-B were modified and successfully prepared into eight novel guaianolide-type STLs (compounds 1-8) bearing ester groups of different geometries. Sal-A, Sal-B, and compounds 1-8 were tested against a human colorectal cancer cell line model with differing p53 status; HCT116 with wild-type p53 and HCT116 p53-/- null for p53, and the normal-like human colon mucosa cells with wild-type p53, NCM460. IC50 values indicated that derivatization of Sal-A and Sal-B resulted in potentiation of HCT116 cell growth inhibition by 97% and 66%, respectively. The effects of the different molecules on cancer cell growth were independent of p53 status. Interestingly, the derivatization of Sal-A and Sal-B molecules enhanced their anti-growth properties versus 5-Fluorouracil (5-FU), which is the drug of choice in colorectal cancer. Structure-activity analysis revealed that the enhanced molecule potencies were mainly attributed to the position and number of the hydroxy groups, the lipophilicity, and the superiority of ester groups over hydroxy substituents in terms of their branching and chain lengths. The favorable cytotoxicity and selectivity of the potent molecules, to cancer cells versus their normal counterparts, pointed them out as promising leads for anti-cancer drug design.


Sujet(s)
Antinéoplasiques d'origine végétale/composition chimique , Antinéoplasiques d'origine végétale/pharmacologie , Tumeurs colorectales/traitement médicamenteux , Composés hétérocycliques 3 noyaux/composition chimique , Antinéoplasiques d'origine végétale/synthèse chimique , Centaurea/composition chimique , Tumeurs colorectales/anatomopathologie , Cystéine/composition chimique , Tests de criblage d'agents antitumoraux , Cellules HCT116 , Humains , Plantes médicinales/composition chimique , Relation structure-activité
12.
J Biol Chem ; 297(4): 101092, 2021 10.
Article de Anglais | MEDLINE | ID: mdl-34437903

RÉSUMÉ

Witchweed, or Striga hermonthica, is a parasitic weed that destroys billions of dollars' worth of crops globally every year. Its germination is stimulated by strigolactones exuded by its host plants. Despite high sequence, structure, and ligand-binding site conservation across different plant species, one strigolactone receptor in witchweed, ShHTL7, uniquely exhibits a picomolar EC50 for downstream signaling. Previous biochemical and structural analyses have hypothesized that this unique ligand sensitivity can be attributed to a large binding pocket volume in ShHTL7 resulting in enhanced ability to bind substrates, but additional structural details of the substrate-binding process would help explain its role in modulating the ligand selectivity. Using long-timescale molecular dynamics simulations, we demonstrate that mutations at the entrance of the binding pocket facilitate a more direct ligand-binding pathway to ShHTL7, whereas hydrophobicity at the binding pocket entrance results in a stable "anchored" state. We also demonstrate that several residues on the D-loop of AtD14 stabilize catalytically inactive conformations. Finally, we show that strigolactone selectivity is not modulated by binding pocket volume. Our results indicate that while ligand binding is not the sole modulator of strigolactone receptor selectivity, it is a significant contributing factor. These results can be used to inform the design of selective antagonists for strigolactone receptors in witchweed.


Sujet(s)
Composés hétérocycliques 3 noyaux/composition chimique , Lactones/composition chimique , Simulation de dynamique moléculaire , Protéines végétales/composition chimique , Striga/composition chimique , Sites de fixation , Composés hétérocycliques 3 noyaux/métabolisme , Lactones/métabolisme , Protéines végétales/génétique , Protéines végétales/métabolisme , Striga/génétique , Striga/métabolisme
13.
Molecules ; 26(16)2021 Aug 22.
Article de Anglais | MEDLINE | ID: mdl-34443671

RÉSUMÉ

Functional organic dyes play a key role in many fields, namely in biotechnology and medical diagnosis. Herein, we report two novel 2,3- and 3,4-dihydroxyphenyl substituted rosamines (3 and 4, respectively) that were successfully synthesized through a microwave-assisted protocol. The best reaction yields were obtained for rosamine 4, which also showed the most interesting photophysical properties, specially toward biogenic amines (BAs). Several amines including n- and t-butylamine, cadaverine, and putrescine cause spectral changes of 4, in UV-Vis and fluorescence spectra, which are indicative of their potential application as an effective tool to detect amines in acetonitrile solutions. In the gas phase, the probe response is more expressive for spermine and putrescine. Additionally, we found that methanolic solutions of rosamine 4 and n-butylamine undergo a pink to yellow color change over time, which has been attributed to the formation of a new compound. The latter was isolated and identified as 5 (9-aminopyronin), whose solutions exhibit a remarkable increase in fluorescence intensity together with a shift toward more energetic wavelengths. Other 9-aminopyronins 6a, 6b, 7a, and 7b were obtained from methanolic solutions of 4 with putrescine and cadaverine, demonstrating the potential of this new xanthene entity to react with primary amines.


Sujet(s)
Amines biogènes/composition chimique , Catéchols/composition chimique , Agents colorants/synthèse chimique , Composés hétérocycliques 3 noyaux/synthèse chimique , Rhodamines/synthèse chimique , Agents colorants/composition chimique , Fluorescence , Composés hétérocycliques 3 noyaux/composition chimique , Rhodamines/composition chimique , Analyse spectrale
14.
J Med Chem ; 64(16): 12003-12021, 2021 08 26.
Article de Anglais | MEDLINE | ID: mdl-34351166

RÉSUMÉ

The expanded polyglutamine-containing mutant huntingtin (mHTT) protein is implicated in neuronal degeneration of medium spiny neurons in Huntington's disease (HD) for which multiple therapeutic approaches are currently being evaluated to eliminate or reduce mHTT. Development of effective and orthogonal biomarkers will ensure accurate assessment of the safety and efficacy of pharmacologic interventions. We have identified and optimized a class of ligands that bind to oligomerized/aggregated mHTT, which is a hallmark in the HD postmortem brain. These ligands are potentially useful imaging biomarkers for HD therapeutic development in both preclinical and clinical settings. We describe here the optimization of the benzo[4,5]imidazo[1,2-a]pyrimidine series that show selective binding to mHTT aggregates over Aß- and/or tau-aggregates associated with Alzheimer's disease pathology. Compound [11C]-2 was selected as a clinical candidate based on its high free fraction in the brain, specific binding in the HD mouse model, and rapid brain uptake/washout in nonhuman primate positron emission tomography imaging studies.


Sujet(s)
Encéphale/imagerie diagnostique , Composés hétérocycliques 3 noyaux/composition chimique , Protéine huntingtine/métabolisme , Agrégats de protéines/physiologie , Pyridines/composition chimique , Radiopharmaceutiques/composition chimique , Maladie d'Alzheimer , Animaux , Marqueurs biologiques/métabolisme , Encéphale/métabolisme , Radio-isotopes du carbone/composition chimique , Femelle , Composés hétérocycliques 3 noyaux/synthèse chimique , Composés hétérocycliques 3 noyaux/pharmacocinétique , Humains , Macaca fascicularis , Mâle , Souris de lignée C57BL , Structure moléculaire , Tomographie par émission de positons , Pyridines/synthèse chimique , Pyridines/pharmacocinétique , Radiopharmaceutiques/synthèse chimique , Radiopharmaceutiques/pharmacocinétique , Rat Sprague-Dawley , Relation structure-activité
15.
Chem Pharm Bull (Tokyo) ; 69(8): 760-767, 2021.
Article de Anglais | MEDLINE | ID: mdl-34334519

RÉSUMÉ

Daldinins are a novel type of naturally occurring tricyclic heterocycles isolated from Daldinia concentrica. In this study, four daldinin A derivatives with different alkyl side chains were synthesized using the same synthetic protocol. Bioactivity tests first indicated that the daldinin A derivatives showed significant protection for endothelial cells against damage caused by high glucose. The derivative compound with three carbon atoms on the alkyl side exhibited the best effect.


Sujet(s)
Découverte de médicament , Cellules endothéliales/effets des médicaments et des substances chimiques , Composés hétérocycliques 3 noyaux/pharmacologie , Hyperglycémie/traitement médicamenteux , Ascomycota/composition chimique , Mort cellulaire/effets des médicaments et des substances chimiques , Cellules endothéliales/métabolisme , Composés hétérocycliques 3 noyaux/synthèse chimique , Composés hétérocycliques 3 noyaux/composition chimique , Humains , Hyperglycémie/métabolisme , Structure moléculaire
16.
Molecules ; 26(13)2021 Jun 24.
Article de Anglais | MEDLINE | ID: mdl-34202721

RÉSUMÉ

Marine natural products are abundant resources for antioxidants, but the antioxidant property of the soft corals-derived sinularin and dihydrosinularin were unknown. This study aimed to assess antioxidant potential and antiproliferation effects of above compounds on cancer cells, and to investigate the possible relationships between them. Results show that sinularin and dihydrosinularin promptly reacted with 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2-azinobis (3-ethyl-benzothiazoline-6-sulfonic acid) (ABTS), and hydroxyl (•OH), demonstrating a general radical scavenger activity. Sinularin and dihydrosinularin also show an induction for Fe+3-reduction and Fe+2-chelating capacity which both strengthen their antioxidant activities. Importantly, sinularin shows higher antioxidant properties than dihydrosinularin. Moreover, 24 h ATP assays show that sinularin leads to higher antiproliferation of breast, lung, and liver cancer cells than dihydrosinularin. Therefore, the differential antioxidant properties of sinularin and dihydrosinularin may contribute to their differential anti-proliferation of different cancer cells.


Sujet(s)
Anthozoa/composition chimique , Antinéoplasiques , Antioxydants , Diterpènes , Composés hétérocycliques 3 noyaux , Tumeurs/traitement médicamenteux , Animaux , Antinéoplasiques/composition chimique , Antinéoplasiques/isolement et purification , Antinéoplasiques/pharmacologie , Antioxydants/composition chimique , Antioxydants/isolement et purification , Antioxydants/pharmacologie , Lignée cellulaire tumorale , Diterpènes/composition chimique , Diterpènes/isolement et purification , Diterpènes/pharmacologie , Composés hétérocycliques 3 noyaux/composition chimique , Composés hétérocycliques 3 noyaux/isolement et purification , Composés hétérocycliques 3 noyaux/pharmacologie , Humains , Tumeurs/métabolisme , Tumeurs/anatomopathologie
17.
Molecules ; 26(10)2021 May 11.
Article de Anglais | MEDLINE | ID: mdl-34064812

RÉSUMÉ

A novel approach for synthesizing the key dolutegravir intermediate is described via MgBr2-promoted intramolecular cyclization. Condensation of commercially available methyl oxalyl chloride and ethyl 3-(N,N-dimethylamino)acrylate afforded the vinylogous amide in an excellent yield. Subsequent substitution by aminoacetaldehyde dimethyl acetal and methyl bromoacetate gave rise to the expected precursor for cyclization, which was promoted by MgBr2 to highly selectively convert into pyridinone diester. The key dolutegravir intermediate was finally prepared by the selective hydrolysis of the corresponding diester via LiOH.


Sujet(s)
Bromures/composition chimique , Composés hétérocycliques 3 noyaux/composition chimique , Composés du magnésium/composition chimique , Oxazines/composition chimique , Pipérazines/composition chimique , Pyridones/composition chimique , Cyclisation , Composés hétérocycliques 3 noyaux/synthèse chimique , Hydrolyse , Oxazines/synthèse chimique , Pipérazines/synthèse chimique , Pyridones/synthèse chimique , Température
18.
Mikrochim Acta ; 188(6): 211, 2021 05 28.
Article de Anglais | MEDLINE | ID: mdl-34050442

RÉSUMÉ

A porous nanostructured covalent-organic framework (COF) has been prepared via condensation polymerization between the two building blocks of melem and hexaketocyclohexane octahydrate (represented as M-HO-COF). Basic characterizations revealed that the M-HO-COF network was composed of C=N and highly conjugated aromatic moieties, along with a high surface area, large pore size, remarkable electrochemical activity, and strong bioaffinity toward aptamer strands. Given that the vascular endothelial growth factor 165 (VEGF165)-targeted aptamer was stably anchored over M-HO-COF via weak intermolecular forces, the prepared M-HO-COF network exhibited great potential as a sensitive and selective platform for the impedimetric VEGF165 aptasensor. Consequently, the M-HO-COF-based aptasensor displayed an ultralow limit of detection of 0.18 fg mL-1 within a wide range of VEGF165 concentrations from 1 fg mL-1 to 10 ng mL-1. Considering its strong fluorescence performance, excellent biocompatibility, and small nanosheet-like structure, the obtained COF-based aptasensor showed a superior sensing performance and regeneration capability after 7 regeneration cycles for the detection of osteosarcoma cells (K7M2 cells), which overexpressed with VEGF165, with a low limit of detection of 49 cells mL-1. For real f human serum samples, the obtained COF-based aptasensor exhibits acceptable mean apparent recoveries of 97.41% with a relative standard deviation of 4.60%. Furthermore, the proposed bifunctional aptasensor for the detection VEGF165 and K7M2 cells exhibited good stability, appropriate selectivity toward other biomarkers or normal cells, acceptable reproducibility, and applicability. A bifunctional sensing system was constructed for detecting osteosarcoma cells (K7M2 cells) and VEGF165 based on the a porous nanostructured covalent-organic framework (M-HO-COF) via condensation polymerization between melem and hexaketocyclohexane octahydrate. The M-HO-COF-based aptasensor displayed ultralow detection limit of 0.18 fg mL-1 toward VEGF165 and 49 cell mL-1 for K7M2 cells with high selectivity, acceptable reproducibility, and good stability.


Sujet(s)
Aptamères nucléotidiques/composition chimique , Techniques électrochimiques/méthodes , Réseaux organométalliques/composition chimique , Facteur de croissance endothéliale vasculaire de type A/analyse , Aptamères nucléotidiques/métabolisme , Marqueurs biologiques tumoraux/sang , Lignée cellulaire tumorale , Cyclohexanes/composition chimique , Composés hétérocycliques 3 noyaux/composition chimique , Humains , Limite de détection , Triazines/composition chimique , Facteur de croissance endothéliale vasculaire de type A/sang
19.
Food Funct ; 12(8): 3692-3704, 2021 Apr 21.
Article de Anglais | MEDLINE | ID: mdl-33900309

RÉSUMÉ

Monascin (MS) and ankaflavin (AK), as typical yellow lipid-soluble pigments identified from Monascus-fermented products, have been confirmed to possess diverse biological activities such as anti-oxidation, reversing diabetes, and anti-atherosclerosis, and have received increasing attention in recent years. Certainly Monascus-fermented product with a high content of MS/AK is also a concern. The current work explored interactions between MS/AK and human serum albumin (HSA) as well as their influence on the anti-oxidant properties of MS/AK. Moreover, the anti-glycation potential of Monascus-fermented products rich in MS and AK (denoted as Mps) was assessed. The results showed that the fluorescence emission of HSA was quenched by MS/AK through a static quenching mechanism, and MS-HSA and AK-HSA complexes were mainly formed by van der Waals forces and hydrophobic interactions, but AK showed a higher binding affinity than MS. Although the DPPH radical-scavenging abilities of MS-HSA and AK-HSA complexes declined, Mps significantly reduced the formation of fructosamine, α-dicarbonyl compounds and advanced glycation end products (AGEs) in the in vitro glycation model (HSA-glucose). Notably, approximately 80% of fluorescent-AGEs were suppressed by Mps at a concentration of 0.95 mg mL-1, while aminoguanidine (AG, a reference standard) caused only 65% decrease at the same concentration. Although radical scavenging and metal chelating activities could justify the observed anti-glycation activity of Mps, in-depth research on the structures of other functional compounds present in Mps except MS/AK and reaction mechanisms should be performed. Overall, the present study proved that Mps would be promising sources of food-based anti-glycation agents because of their superior inhibitory effect on AGEs.


Sujet(s)
Antioxydants/pharmacologie , Flavines/pharmacologie , Composés hétérocycliques 3 noyaux/pharmacologie , Monascus , Antioxydants/composition chimique , Flavines/composition chimique , Glycosylation/effets des médicaments et des substances chimiques , Composés hétérocycliques 3 noyaux/composition chimique , Humains , Sérum-albumine humaine/effets des médicaments et des substances chimiques
20.
BMC Infect Dis ; 21(1): 379, 2021 Apr 23.
Article de Anglais | MEDLINE | ID: mdl-33892628

RÉSUMÉ

BACKGROUND: The Integrase (IN) strand transfer inhibitor (INSTI), Dolutegravir (DTG), has been given the green light to form part of first-line combination antiretroviral therapy (cART) by the World Health Organization (WHO). DTG containing regimens have shown a high genetic barrier against HIV-1 isolates carrying specific resistance mutations when compared with other class of regimens. METHODS: We evaluated the HIV-1 CRF02_AG IN gene sequences from Cameroon for the presence of resistance-associated mutations (RAMs) against INSTIs and naturally occurring polymorphisms (NOPs), using study sequences (n = 20) and (n = 287) sequences data derived from HIV Los Alamos National Laboratory database. The possible impact of NOPs on protein structure caused by HIV-1 CRF02_AG variations was addressed within the context of a 3D model of the HIV-1 IN complex and interaction analysis was performed using PyMol to validate DTG binding to the Wild type and seven mutant structures. RESULTS: We observed 12.8% (37/287) sequences to contain RAMs, with only 1.0% (3/287) of the sequences having major INSTI RAMs: T66A, Q148H, R263K and N155H. Of these,11.8% (34/287) of the sequences contained five different IN accessory mutations; namely Q95K, T97A, G149A, E157Q and D232N. NOPs occurred at a frequency of 66% on the central core domain (CCD) position, 44% on the C-terminal domain (CTD) position and 35% of the N-terminal domain (NTD) position. The interaction analysis revealed that DTG bound to DNA, 2MG ions and DDE motif residues for T66A, T97A, Q148H, N155H and R263K comparable to the WT structure. Except for accessory mutant structure E157Q, only one MG contact was made with DTG, while DTG had no MG ion contacts and no DDE motif residue contacts for structure D232N. CONCLUSIONS: Our analysis indicated that all RAM's that resulted in a change in the number of interactions with encompassing residues does not affect DTG binding, while accessory mutations E157Q and D232N could affect DTG binding leading to possible DTG resistance. However, further experimental validation is required to validate the in silico findings of our study.


Sujet(s)
Résistance virale aux médicaments/génétique , Infections à VIH/traitement médicamenteux , Inhibiteurs de l'intégrase du VIH/usage thérapeutique , Intégrase du VIH/génétique , VIH-1 (Virus de l'Immunodéficience Humaine de type 1)/enzymologie , Composés hétérocycliques 3 noyaux/usage thérapeutique , Modèles moléculaires , Mutation , Oxazines/usage thérapeutique , Pipérazines/usage thérapeutique , Pyridones/usage thérapeutique , Cameroun/épidémiologie , Infections à VIH/épidémiologie , Infections à VIH/virologie , Intégrase du VIH/composition chimique , Inhibiteurs de l'intégrase du VIH/composition chimique , Composés hétérocycliques 3 noyaux/composition chimique , Humains , Oxazines/composition chimique , Phylogenèse , Pipérazines/composition chimique , Polymorphisme génétique , Pyridones/composition chimique
SÉLECTION CITATIONS
DÉTAIL DE RECHERCHE