ABSTRACT
Lecithin:retinol acyltransferase (LRAT) is the main enzyme catalysing the esterification of retinol to retinyl esters and, hence, is of central importance for retinol homeostasis. As retinol, by its metabolite retinoic acid, stimulates fibroblasts to synthesize collagen fibres and inhibits collagen-degrading enzymes, the inhibition of LRAT presents an intriguing strategy for anti-ageing ingredients by increasing the available retinol in the skin. Here, we synthesized several derivatives mimicking natural lecithin substrates as potential LRAT inhibitors. By exploring various chemical modifications of the core scaffold consisting of a central amino acid and an N-terminal acylsulfone, we explored 10 different compounds in a biochemical assay, resulting in two compounds with IC50 values of 21.1 and 32.7 µM (compounds 1 and 2), along with a simpler arginine derivative with comparative inhibitory potency. Supported by computational methods, we investigated their structure-activity relationship, resulting in the identification of several structural features associated with high inhibition of LRAT. Ultimately, we conducted an ex vivo study with human skin, demonstrating an increase of collagen III associated with a reduction of the skin ageing process. In conclusion, the reported compounds offer a promising approach to boost retinol abundance in human skin and might present a new generation of anti-ageing ingredients for cosmetic application.
La lécithine/rétinol acyltransférase (LRAT) est la principale enzyme qui catalyse l'estérification du rétinol en esters de rétinyle et, par conséquent, est d'une importance centrale pour l'homéostasie du rétinol. Étant donné que le rétinol, par son métabolite l'acide rétinoïque, stimule les fibroblastes pour synthétiser les fibres de collagène et inhibe les enzymes de dégradation du collagène, l'inhibition de la LRAT constitue une stratégie intéressante pour les ingrédients antiâge en augmentant le rétinol disponible dans la peau. Ici, nous avons synthétisé plusieurs dérivés imitant les substrats naturels de la lécithine comme inhibiteurs de LRAT potentiels. En étudiant différentes modifications chimiques du noyau composé d'un acide aminé central et d'un acylsulfone Nterminal, nous avons étudié dix composés différents dans le cadre d'un essai biochimique; il en est résulté deux composés avec des valeurs de CI50 de 21.1 et 32.7 µm (composés 1 et 2), ainsi qu'un dérivé d'arginine plus simple avec une puissance inhibitrice comparative. Avec le soutien de méthodes computationnelles, nous avons étudié leur relation structureactivité, ce qui a permis d'identifier plusieurs caractéristiques structurelles associées à une inhibition élevée de la LRAT. Enfin, nous avons mené une étude ex vivo sur la peau humaine, démontrant une augmentation du collagène III associée à une réduction du processus de vieillissement de la peau. En conclusion, les composés rapportés offrent une approche prometteuse pour stimuler l'abondance du rétinol dans la peau humaine et pourraient aboutir à une nouvelle génération d'ingrédients antiâge pour des applications cosmétiques.
Subject(s)
Acyltransferases , Enzyme Inhibitors , Vitamin A , Vitamin A/pharmacology , Acyltransferases/antagonists & inhibitors , Humans , Enzyme Inhibitors/pharmacology , Enzyme Inhibitors/chemistry , Structure-Activity Relationship , Skin/drug effects , Skin/metabolismABSTRACT
Researchers are increasingly interested in discovering new pancreatic lipase inhibitors as anti-obesity ingredients. Medicine-and-food homology plants contain a diverse set of natural bioactive compounds with promising development potential. This study screened and identified potent pancreatic lipase inhibitors from 20 commonly consumed medicine-and-food homology plants using affinity ultrafiltration combined with spectroscopy and docking simulations. The results showed that turmeric exhibited the highest pancreatic lipase-inhibitory activity, and curcumin, demethoxycurcumin, and bisdemethoxycurcumin were discovered to be potent pancreatic lipase inhibitors within the turmeric extract, with IC50 values of 0.52 ± 0.04, 1.12 ± 0.05, and 3.30 ± 0.08 mg/mL, respectively. In addition, the enzymatic kinetics analyses demonstrated that the inhibition type of the three curcuminoids was the reversible competitive model, and curcumin exhibited a higher binding affinity and greater impact on the secondary structure of pancreatic lipase than found with demethoxycurcumin or bisdemethoxycurcumin, as observed through fluorescence spectroscopy and circular dichroism. Furthermore, docking simulations supported the above experimental findings, and revealed that the three curcuminoids might interact with amino acid residues in the binding pocket of pancreatic lipase through non-covalent actions, such as hydrogen bonding and π-π stacking, thereby inhibiting the pancreatic lipase. Collectively, these findings suggest that the bioactive compounds of turmeric, in particular curcumin, can be promising dietary pancreatic lipase inhibitors for the prevention and management of obesity.
Subject(s)
Curcuma , Curcumin , Diarylheptanoids , Enzyme Inhibitors , Lipase , Molecular Docking Simulation , Pancreas , Lipase/antagonists & inhibitors , Curcumin/pharmacology , Curcumin/analogs & derivatives , Curcumin/chemistry , Curcuma/chemistry , Diarylheptanoids/pharmacology , Pancreas/enzymology , Enzyme Inhibitors/pharmacology , Enzyme Inhibitors/chemistry , Plant Extracts/pharmacology , Plant Extracts/chemistry , Humans , Plants, Medicinal/chemistryABSTRACT
The benzofuran core inhibitors HCV-796, BMS-929075, MK-8876, compound 2, and compound 9B exhibit good pan-genotypic activity against various genotypes of NS5B polymerase. To elucidate their mechanism of action, multiple molecular simulation methods were used to investigate the complex systems of these inhibitors binding to GT1a, 1b, 2a, and 2b NS5B polymerases. The calculation results indicated that these five inhibitors can not only interact with the residues in the palm II subdomain of NS5B polymerase, but also with the residues in the palm I subdomain or the palm I/III overlap region. Interestingly, the binding of inhibitors with longer substituents at the C5 position (BMS-929075, MK-8876, compound 2, and compound 9B) to the GT1a and 2b NS5B polymerases exhibits different binding patterns compared to the binding to the GT1b and 2a NS5B polymerases. The interactions between the para-fluorophenyl groups at the C2 positions of the inhibitors and the residues at the binding pockets, together with the interactions between the substituents at the C5 positions and the residues at the reverse ß-fold (residues 441-456), play a key role in recognition and the induction of the binding. The relevant studies could provide valuable information for further research and development of novel anti-HCV benzofuran core pan-genotypic inhibitors.
Subject(s)
Antiviral Agents , Benzofurans , Genotype , Hepacivirus , Viral Nonstructural Proteins , Viral Nonstructural Proteins/antagonists & inhibitors , Viral Nonstructural Proteins/metabolism , Viral Nonstructural Proteins/chemistry , Benzofurans/chemistry , Benzofurans/pharmacology , Hepacivirus/drug effects , Hepacivirus/enzymology , Hepacivirus/genetics , Antiviral Agents/pharmacology , Antiviral Agents/chemistry , Molecular Dynamics Simulation , Molecular Docking Simulation , Binding Sites , Protein Binding , Humans , Enzyme Inhibitors/pharmacology , Enzyme Inhibitors/chemistry , RNA-Dependent RNA PolymeraseABSTRACT
DNA polymerase theta (Polθ) is a DNA helicase-polymerase protein that facilitates DNA repair and is synthetic lethal with homology-directed repair (HDR) factors. Thus, Polθ is a promising precision oncology drug-target in HDR-deficient cancers. Here, we characterize the binding and mechanism of action of a Polθ helicase (Polθ-hel) small-molecule inhibitor (AB25583) using cryo-EM. AB25583 exhibits 6 nM IC50 against Polθ-hel, selectively kills BRCA1/2-deficient cells, and acts synergistically with olaparib in cancer cells harboring pathogenic BRCA1/2 mutations. Cryo-EM uncovers predominantly dimeric Polθ-hel:AB25583 complex structures at 3.0-3.2 Å. The structures reveal a binding-pocket deep inside the helicase central-channel, which underscores the high specificity and potency of AB25583. The cryo-EM structures in conjunction with biochemical data indicate that AB25583 inhibits the ATPase activity of Polθ-hel helicase via an allosteric mechanism. These detailed structural data and insights about AB25583 inhibition pave the way for accelerating drug development targeting Polθ-hel in HDR-deficient cancers.
Subject(s)
Cryoelectron Microscopy , DNA Helicases , DNA Polymerase theta , DNA-Directed DNA Polymerase , Humans , DNA Helicases/metabolism , DNA Helicases/chemistry , DNA Helicases/genetics , DNA Helicases/antagonists & inhibitors , DNA-Directed DNA Polymerase/metabolism , DNA-Directed DNA Polymerase/chemistry , DNA-Directed DNA Polymerase/genetics , BRCA2 Protein/metabolism , BRCA2 Protein/genetics , BRCA2 Protein/chemistry , BRCA1 Protein/metabolism , BRCA1 Protein/genetics , BRCA1 Protein/chemistry , Piperazines/pharmacology , Piperazines/chemistry , Cell Line, Tumor , Phthalazines/pharmacology , Phthalazines/chemistry , Enzyme Inhibitors/pharmacology , Enzyme Inhibitors/chemistry , Models, Molecular , Adenosine Triphosphatases/metabolism , Adenosine Triphosphatases/antagonists & inhibitors , Protein BindingABSTRACT
Lactate dehydrogenase A (LDHA) is highly expressed in many tumor cells and promotes the conversion of pyruvate to lactic acid in the glucose pathway, providing energy and synthetic precursors for rapid proliferation of tumor cells. Therefore, inhibition of LDHA has become a widely concerned tumor treatment strategy. However, the research and development of highly efficient and low toxic LDHA small molecule inhibitors still faces challenges. To discover potential inhibitors against LDHA, virtual screening based on molecular docking techniques was performed from Specs database of more than 260,000 compounds and Chemdiv-smart database of more than 1,000 compounds. Through molecular dynamics (MD) simulation studies, we identified 12 potential LDHA inhibitors, all of which can stably bind to human LDHA protein and form multiple interactions with its active central residues. In order to verify the inhibitory activities of these compounds, we established an enzyme activity assay system and measured their inhibitory effects on recombinant human LDHA. The results showed that Compound 6 could inhibit the catalytic effect of LDHA on pyruvate in a dose-dependent manner with an EC50 value of 14.54 ± 0.83 µM. Further in vitro experiments showed that Compound 6 could significantly inhibit the proliferation of various tumor cell lines such as pancreatic cancer cells and lung cancer cells, reduce intracellular lactic acid content and increase intracellular reactive oxygen species (ROS) level. In summary, through virtual screening and in vitro validation, we found that Compound 6 is a small molecule inhibitor for LDHA, providing a good lead compound for the research and development of LDHA related targeted anti-tumor drugs.
Subject(s)
Enzyme Inhibitors , High-Throughput Screening Assays , Molecular Docking Simulation , Molecular Dynamics Simulation , Humans , Enzyme Inhibitors/pharmacology , Enzyme Inhibitors/chemistry , High-Throughput Screening Assays/methods , Cell Proliferation/drug effects , Antineoplastic Agents/pharmacology , Antineoplastic Agents/chemistry , L-Lactate Dehydrogenase/antagonists & inhibitors , L-Lactate Dehydrogenase/metabolism , L-Lactate Dehydrogenase/chemistry , Cell Line, TumorABSTRACT
Synergistic interactions between chemical inhibitors, whilst informative, can be difficult to interpret, as chemical inhibitors can often have multiple targets, many of which can be unknown. Here, using multiplexed transcriptional repression, we have validated that the simultaneous repression of glutamate racemase and alanine racemase has a synergistic interaction in Mycobacterium tuberculosis. This confirms prior observations from chemical interaction studies and highlights the potential of targeting multiple enzymes involved in mycobacterial cell wall synthesis.
Subject(s)
Alanine Racemase , Amino Acid Isomerases , Mycobacterium tuberculosis , Mycobacterium tuberculosis/genetics , Mycobacterium tuberculosis/enzymology , Mycobacterium tuberculosis/drug effects , Amino Acid Isomerases/genetics , Amino Acid Isomerases/metabolism , Alanine Racemase/genetics , Alanine Racemase/metabolism , Gene Expression Regulation, Bacterial , Transcription, Genetic , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Enzyme Inhibitors/pharmacology , Cell Wall/metabolism , Cell Wall/geneticsABSTRACT
Eleutherococcus divaricatus (Siebold and Zucc.) S. Y. Hu. has been used in Traditional Chinese Medicine (TCM) due to its anticancer, immunostimulant, and anti-inflammatory activities. However, its mechanism of action and chemical composition are still insufficiently understood and require more advanced research, especially for cases in which anti-inflammatory properties are beneficial. The aim of this study was to evaluate the impact of E. divaricatus root extracts and fractions on proinflammatory serum hyaluronidase and tyrosinase in children diagnosed with acute lymphoblastic leukemia. Antioxidant and anti-melanoma activities were also examined and correlated with metabolomic data. For the first time, we discovered that the ethyl acetate fraction significantly inhibits hyaluronidase activity, with mean group values of 55.82% and 63.8% for aescin used as a control. However, interestingly, the fraction showed no activity against human tyrosinase, and in A375 melanoma cells treated with a doxorubicin fraction, doxorubicin activity decreased. This fraction exhibited the most potent antioxidant activity, which can be attributed to high contents of polyphenols, especially caffeic acid (24 mg/g). The findings suggest an important role of the ethyl acetate fraction in hyaluronidase inhibition, which may additionally indicate its anti-inflammatory property. The results suggest that this fraction can be used in inflammatory-related diseases, although with precautions in cases of patients undergoing chemotherapy.
Subject(s)
Acetates , Antioxidants , Eleutherococcus , Hyaluronoglucosaminidase , Melanoma , Monophenol Monooxygenase , Plant Extracts , Plant Roots , Hyaluronoglucosaminidase/antagonists & inhibitors , Hyaluronoglucosaminidase/metabolism , Monophenol Monooxygenase/antagonists & inhibitors , Monophenol Monooxygenase/metabolism , Humans , Antioxidants/pharmacology , Antioxidants/chemistry , Plant Roots/chemistry , Plant Extracts/chemistry , Plant Extracts/pharmacology , Melanoma/drug therapy , Melanoma/metabolism , Acetates/chemistry , Eleutherococcus/chemistry , Cell Line, Tumor , Enzyme Inhibitors/pharmacology , Enzyme Inhibitors/chemistryABSTRACT
4-Hydroxyphenylpyruvate dioxygenase inhibiting herbicides (HIHs) represent a recent class (HRAC group 27) of herbicides that offer many advantages, such as broad-spectrum activity, crop selectivity, and low resistance rates. However, emerging studies have highlighted the potential toxicity of HIHs in the environment. This review aims to provide a comprehensive summary of the toxicity of HIHs toward nontarget organisms, including plants, microorganisms, animals, and humans. Furthermore, the present work discusses the ecological roles of these organisms in the environment and their significance in agriculture. By shedding light on the toxicity of HIHs, this study seeks to raise awareness among end users, including environmentalists, researchers, and farmers, regarding the potential ecological implications of these herbicides. Hopefully, this knowledge can contribute to informed decision-making and sustainable practices in green agriculture and environmental management.
Subject(s)
4-Hydroxyphenylpyruvate Dioxygenase , Herbicides , Herbicides/toxicity , 4-Hydroxyphenylpyruvate Dioxygenase/antagonists & inhibitors , 4-Hydroxyphenylpyruvate Dioxygenase/metabolism , Humans , Animals , Enzyme Inhibitors/toxicity , Plants/drug effectsABSTRACT
Melanin biosynthesis in different organisms is performed by a tyrosinase action. Excessive enzyme activity and pigment accumulation result in different diseases and disorders including skin cancers, blemishes, and darkening. In fruits and vegetables, it causes unwanted browning of these products and reduces their appearance quality and economic value. Inhibiting enzyme activity and finding novel powerful and safe inhibitors are highly important in agriculture, food, medical, and pharmaceutical industries. In this regard, in the present study, some novel synthetic pyridine-based compounds including 2,6-bis (tosyloxymethyl) pyridine (compound 3), 2,6-bis (butylthiomethyl) pyridine (compound 4), and 2,6-bis (phenylthiomethyl) pyridine (compound 5) were synthesized for the first time, and their inhibitory potencies were assessed on mushroom tyrosinase diphenolase activity. The results showed that while all tested compounds significantly decreased the enzyme activity, compounds 4 and 5 had the highest inhibitory effects (respectively, 80 and 89% inhibition with the IC50 values of 17.0 and 9.0 µmol L-1), and the inhibition mechanism was mixed-type for both compounds. Ligand-binding studies were carried out by fluorescence quenching and molecular docking methods to investigate the enzyme-compound interactions. Fluorescence quenching results revealed that the compounds can form nonfluorescent complexes with the enzyme and result in quenching of its intrinsic emission by the static process. Molecular docking analyses predicted the binding positions and the amino acid residues involved in the interactions. These compounds appear to be suitable candidates for more studies on tyrosinase inhibition.
Subject(s)
Agaricales , Enzyme Inhibitors , Molecular Docking Simulation , Monophenol Monooxygenase , Pyridines , Monophenol Monooxygenase/antagonists & inhibitors , Monophenol Monooxygenase/chemistry , Monophenol Monooxygenase/metabolism , Agaricales/enzymology , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/pharmacology , Pyridines/chemistry , Pyridines/pharmacology , Spectrometry, Fluorescence , Fungal Proteins/antagonists & inhibitors , Fungal Proteins/chemistry , Fungal Proteins/metabolismABSTRACT
Chikungunya virus (CHIKV), transmitted by mosquitoes, poses a significant global health threat. Presently, no effective treatment options are available to reduce the disease burden. The lack of approved therapeutics against CHIKV and the complex spectrum of chronic musculoskeletal and neurological manifestations raise significant concerns, and repurposing drugs could offer swift avenues in the development of effective treatment strategies. RNA capping is a crucial step meditated by non-structural protein 1 (nsP1) in CHIKV replication. In this study, FDA-approved antivirals targeting CHIKV nsP1 methyltransferase (MTase) have been identified by structure-based virtual screening. Berbamine Hydrochloride (BH), ABT199/Venetoclax (ABT), and Ponatinib (PT) were the top-hits, which exhibited robust binding energies. Tryptophan fluorescence spectroscopy-based assay confirmed binding of BH-, ABT-, and PT to purified nsP1 with KD values â¼5.45 µM, â¼161.3 µM, and â¼3.83 µM, respectively. In a capillary electrophoresis-based assay, a decrease in CHIKV nsP1 MTase activity was observed in a dose-dependent manner. Treatment with BH, ABT, and PT lead to a dose-dependent reduction in the virus titer with IC50 < 100, â¼6.75, and <3.9 nM, respectively, and reduced viral mRNA levels. The nsP1 MTases are highly conserved among alphaviruses; therefore, BH, ABT, and PT, as expected, inhibited replication machinery in Sindbis virus (SINV) replicon assay with IC50 â¼1.94, â¼0.23, and >1.25 µM, respectively. These results highlight the potential of repurposing drugs as rapid and effective antiviral therapeutics against CHIKV.
Subject(s)
Antiviral Agents , Chikungunya virus , Methyltransferases , Antiviral Agents/pharmacology , Antiviral Agents/chemistry , Methyltransferases/antagonists & inhibitors , Methyltransferases/metabolism , Chikungunya virus/drug effects , Animals , Sulfonamides/pharmacology , Sulfonamides/chemistry , Humans , Pyridazines/pharmacology , Pyridazines/chemistry , Enzyme Inhibitors/pharmacology , Enzyme Inhibitors/chemistry , Bridged Bicyclo Compounds, Heterocyclic/pharmacology , Bridged Bicyclo Compounds, Heterocyclic/chemistry , Virus Replication/drug effects , Imidazoles/pharmacology , Imidazoles/chemistry , BenzylisoquinolinesABSTRACT
The current therapies against gastric pathogen Helicobacter pylori are ineffective in over 20% of patients. Enzymes belonging to the purine salvage pathway are considered as novel drug targets in this pathogen. Therefore, the main aim of the current study was to determine the antibacterial activity of pyridoxal 5'-phosphate (PLP), an active form of vitamin B6, against reference and clinical strains of H. pylori. Using a broad set of microbiological, physicochemical (UV absorption, LC-MS, X-ray analysis) and in silico experiments, we were able to prove that PLP inhibits adenylosuccinate synthetase (AdSS) from H. pylori by the competition with GTP (IC50eq â¼30 nM). This behaviour was attributed to formation of a Schiff base with a lysine residue (a covalent bond with Lys322 in the GTP binding site of AdSS) and was potentiated by the presence of vitamin C. This antibacterial activity of PLP gives hope for its future use against H. pylori.
Subject(s)
Adenylosuccinate Synthase , Anti-Bacterial Agents , Dose-Response Relationship, Drug , Helicobacter pylori , Microbial Sensitivity Tests , Vitamin B 6 , Helicobacter pylori/drug effects , Helicobacter pylori/enzymology , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/chemical synthesis , Vitamin B 6/pharmacology , Vitamin B 6/chemistry , Vitamin B 6/chemical synthesis , Structure-Activity Relationship , Adenylosuccinate Synthase/metabolism , Adenylosuccinate Synthase/chemistry , Adenylosuccinate Synthase/antagonists & inhibitors , Adenylosuccinate Synthase/pharmacology , Molecular Structure , Enzyme Inhibitors/pharmacology , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/chemical synthesis , Drug Resistance, Bacterial/drug effects , Pyridoxal Phosphate/pharmacology , Pyridoxal Phosphate/chemistry , Models, MolecularABSTRACT
The present work reports on the preparation of the hitherto unknown title compounds 5, with various synthetic routes described. The initially pursued concept of S-N exchange with varioius 1-substituted 3-methylsulfanyl-5,6,7,8-tetrahydro-1 H -[1,2,4]triazolo[1,2- a ]pyridazines 4 by using nitrogen nucleophiles was only marginally successful. The reactions proceeded slowly and the yields were low, mainly because of the pronounced formation of 5,6,7,8-tetrahydro-[1,2,4]triazolo[1,2- a ]pyridazin-1-imines 7 by oxidation of the heterocyclic amines 5 initially formed. The integration of the synthesis of 3-acylsulfanyl analogues with the more reactive leaving groups also failed. On the other hand, the cyclization of the hydrohalides of hexahydropyridazine-1-carboximidamide with aromatic aldehydes and some low molecular weight ketones gives significantly better results in the synthesis of the title compounds 5. The use of the hydrochloride 6b proved to be advantageous in comparison to the hydroiodide 6a because the yields were significantly better and the imines 7 formed at the same time only to a small extent. In addition, the starting compound 6b can be prepared in a single-step synthesis in very good yield from hexahydropyridazine hydrochloride 1 and cyanamide. The cyclization of N' -phenylhexahydropyridazine-1-carboximidamide hydrochloride 6c with substituted benzaldehydes gives the 3-aryl-substituted 2-phenyl-2,3,5,6,7,8-hexahydro -1H -[1,2,4]triazolo[1,2- a ] pyridazin-1-imines 8. In the context with the study of the reaction of hexahydropyridazine-1-carboximidamide hydroiodide 6a with cyclohexanone, the hexahydropyridazine-1-carboxamide 9 was specifically synthesized. This can be reacted with aromatic aldehydes to give the 5,6,7,8-tetrahydro-1 H -[1,2,4]triazolo[1,2- a ]pyridazin-1-ones 10 in very good yields. The results of the biological testing of representatives of the synthesized 5,6,7,8-tetrahydro-[1,2,4] triazolo[1,2-a]pyridazine-1-amines 5 show, in comparison to the already examined thions 3 and 3-methylsulfanyl derivatives 4, significantly less inducible nitric oxide synthase (iNOS) inhibitory activity.
Subject(s)
Nitric Oxide Synthase Type II , Pyridazines , Pyridazines/chemical synthesis , Pyridazines/chemistry , Pyridazines/pharmacology , Nitric Oxide Synthase Type II/antagonists & inhibitors , Triazoles/chemical synthesis , Triazoles/chemistry , Triazoles/pharmacology , Enzyme Inhibitors/chemical synthesis , Enzyme Inhibitors/pharmacology , Enzyme Inhibitors/chemistry , Structure-Activity Relationship , Amines/chemistry , Amines/chemical synthesis , Magnetic Resonance SpectroscopyABSTRACT
This study examined the suppressive effects of 16 selected plant-based foods on α-glucosidase and pancreatic lipase and their antioxidant properties. Among these, the bark of Cinnamomum cassia (Cinnamon, WLN-FM 15) showed the highest inhibitory activity against α-glucosidase and the highest antioxidant activity. Additionally, WLN-FM 15 showed promising results in the other tests. To further identify the bioactive constituents of WLN-FM 15, a multi-bioactivity-labeled molecular networking approach was used through a combination of GNPS-based molecular networking, DPPH-HPLC, and affinity-based ultrafiltration-HPLC. A total of nine procyanidins were identified as antioxidants and inhibitors of α-glucosidase and pancreatic lipase in WLN-FM 15. Subsequently, procyanidins A1, A2, B1, and C1 were isolated, and their efficacy was confirmed through functional assays. In summary, WLN-FM 15 has the potential to serve as a functional food ingredient with the procyanidins as its bioactive constituents. These results also suggest that the multi-bioactivity-labeled molecular networking approach is reliable for identifying bioactive constituents in plant-based foods.
Subject(s)
Antioxidants , Biflavonoids , Catechin , Cinnamomum aromaticum , Glycoside Hydrolase Inhibitors , Lipase , Plant Bark , Proanthocyanidins , Proanthocyanidins/pharmacology , Proanthocyanidins/chemistry , Proanthocyanidins/analysis , Lipase/antagonists & inhibitors , Lipase/metabolism , Antioxidants/pharmacology , Antioxidants/chemistry , Antioxidants/analysis , Glycoside Hydrolase Inhibitors/pharmacology , Glycoside Hydrolase Inhibitors/chemistry , Plant Bark/chemistry , Cinnamomum aromaticum/chemistry , Biflavonoids/pharmacology , Biflavonoids/analysis , Biflavonoids/chemistry , Catechin/analysis , Catechin/chemistry , Catechin/pharmacology , Plant Extracts/chemistry , Plant Extracts/pharmacology , Chromatography, High Pressure Liquid , Pancreas/enzymology , alpha-Glucosidases/metabolism , Network Pharmacology , Enzyme Inhibitors/pharmacology , Enzyme Inhibitors/chemistryABSTRACT
Δ1-pyrroline-5-carboxylate reductase isoform 1 (PYCR1) is the last enzyme of proline biosynthesis and catalyzes the NAD(P)H-dependent reduction of Δ1-pyrroline-5-carboxylate to L-proline. High PYCR1 gene expression is observed in many cancers and linked to poor patient outcomes and tumor aggressiveness. The knockdown of the PYCR1 gene or the inhibition of PYCR1 enzyme has been shown to inhibit tumorigenesis in cancer cells and animal models of cancer, motivating inhibitor discovery. We screened a library of 71 low molecular weight compounds (average MW of 131 Da) against PYCR1 using an enzyme activity assay. Hit compounds were validated with X-ray crystallography and kinetic assays to determine affinity parameters. The library was counter-screened against human Δ1-pyrroline-5-carboxylate reductase isoform 3 and proline dehydrogenase (PRODH) to assess specificity/promiscuity. Twelve PYCR1 and one PRODH inhibitor crystal structures were determined. Three compounds inhibit PYCR1 with competitive inhibition parameter of 100 µM or lower. Among these, (S)-tetrahydro-2H-pyran-2-carboxylic acid (70 µM) has higher affinity than the current best tool compound N-formyl-l-proline, is 30 times more specific for PYCR1 over human Δ1-pyrroline-5-carboxylate reductase isoform 3, and negligibly inhibits PRODH. Structure-affinity relationships suggest that hydrogen bonding of the heteroatom of this compound is important for binding to PYCR1. The structures of PYCR1 and PRODH complexed with 1-hydroxyethane-1-sulfonate demonstrate that the sulfonate group is a suitable replacement for the carboxylate anchor. This result suggests that the exploration of carboxylic acid isosteres may be a promising strategy for discovering new classes of PYCR1 and PRODH inhibitors. The structure of PYCR1 complexed with l-pipecolate and NADH supports the hypothesis that PYCR1 has an alternative function in lysine metabolism.
Subject(s)
Enzyme Inhibitors , Proline , Pyrroline Carboxylate Reductases , delta-1-Pyrroline-5-Carboxylate Reductase , Pyrroline Carboxylate Reductases/metabolism , Pyrroline Carboxylate Reductases/antagonists & inhibitors , Pyrroline Carboxylate Reductases/chemistry , Pyrroline Carboxylate Reductases/genetics , Humans , Crystallography, X-Ray , Proline/chemistry , Proline/analogs & derivatives , Proline/metabolism , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/pharmacology , Small Molecule Libraries/chemistry , Small Molecule Libraries/pharmacology , Molecular Weight , Proline Oxidase/metabolism , Proline Oxidase/chemistry , Proline Oxidase/antagonists & inhibitors , Proline Oxidase/genetics , Models, MolecularABSTRACT
EcGUS has drawn considerable attention for its role as a target in alleviating serious GIAEs. In this study, a series of 72 (thio)urea derivatives were designed, synthesised, and biologically assayed. The bioassay results revealed that E-9 (IC50 = 2.68 µM) exhibited a promising inhibitory effect on EcGUS, surpassing EcGUS inhibitor D-saccharic acid-1,4-lactone (DSL, IC50 = 45.8 µM). Additionally, the inhibitory kinetic study indicated that E-9 (Ki = 1.64 µM) acted as an uncompetitive inhibitor against EcGUS. The structure-activity relationship revealed that introducing an electron-withdrawing group into the benzene ring at the para-position is beneficial for enhancing inhibitory activity against EcGUS. Furthermore, molecular docking analysis indicated that E-9 has a strong affinity to EcGUS by forming interactions with residues Asp 163, Tyr 472, and Glu 504. Overall, these results suggested that E-9 could be a potent EcGUS inhibitor, providing valuable insights and guidelines for the development of future inhibitors targeting EcGUS.
Subject(s)
Dose-Response Relationship, Drug , Drug Design , Enzyme Inhibitors , Escherichia coli , Glucuronidase , Structure-Activity Relationship , Molecular Structure , Escherichia coli/drug effects , Escherichia coli/enzymology , Enzyme Inhibitors/pharmacology , Enzyme Inhibitors/chemical synthesis , Enzyme Inhibitors/chemistry , Glucuronidase/antagonists & inhibitors , Glucuronidase/metabolism , Molecular Docking Simulation , Thiourea/pharmacology , Thiourea/chemistry , Thiourea/chemical synthesis , GlycoproteinsABSTRACT
The crystallographic structure of the FolB enzyme from Mycobacterium tuberculosis (MtFolB), complexed with its inhibitor 8-mercaptoguanine (8-MG), was elucidated at a resolution of 1.95 Å. A novel series of S8-functionalized 8-MG derivatives were synthesised and evaluated as in vitro inhibitors of dihydroneopterin aldolase (DHNA, EC 4.1.2.25) activity of MtFolB. These compounds exhibited IC50 values in the submicromolar range. Evaluation of the activity for five compounds indicated their inhibition mode and inhibition constants. Molecular docking analyses were performed to determine the enzyme-inhibitor intermolecular interactions and ligand conformations upon complex formation. The inhibitory activities of all compounds against the M. tuberculosis H37Rv strain were evaluated. Compound 3e exhibited a minimum inhibitory concentration in the micromolar range. Finally, Compound 3e showed no apparent toxicity in both HepG2 and Vero cells. The findings presented herein will advance the quest for novel, specific inhibitors targeting MtFolB, an attractive molecular target for TB drug development.
Subject(s)
Aldehyde-Lyases , Antitubercular Agents , Dose-Response Relationship, Drug , Enzyme Inhibitors , Microbial Sensitivity Tests , Mycobacterium tuberculosis , Mycobacterium tuberculosis/drug effects , Mycobacterium tuberculosis/enzymology , Antitubercular Agents/pharmacology , Antitubercular Agents/chemical synthesis , Antitubercular Agents/chemistry , Enzyme Inhibitors/pharmacology , Enzyme Inhibitors/chemical synthesis , Enzyme Inhibitors/chemistry , Humans , Structure-Activity Relationship , Aldehyde-Lyases/antagonists & inhibitors , Aldehyde-Lyases/metabolism , Aldehyde-Lyases/chemistry , Vero Cells , Molecular Structure , Crystallography, X-Ray , Chlorocebus aethiops , Animals , Guanine/pharmacology , Guanine/chemistry , Guanine/analogs & derivatives , Guanine/chemical synthesis , Molecular Docking Simulation , Hep G2 Cells , Models, MolecularABSTRACT
Dysregulation of the mineralocorticoid hormone aldosterone is an increasingly prevalent cause of hypertension. Aldosterone synthase (CYP11B2) shares 93% homology to 11ß-hydroxylase (CYP11B1), which produces cortisol. Lorundrostat, a highly selective inhibitor of CYP11B2, is a potential safe and effective treatment for aldosterone-dependent, uncontrolled hypertension, including treatment-resistant hypertension. Lorundrostat showed highly selective inhibition of CYP11B2 in vitro, with 374-fold selectivity for CYP11B2 vs. CYP11B1. A first-in-human study of single ascending doses ranging from 5 to 800 mg and multiple ascending doses ranging from 40 to 360 mg once daily was conducted in healthy participants. After single- and multiple-dose administration, lorundrostat plasma levels peaked 1-3 h after administration with a t1/2 of 10-12 h. Plasma aldosterone decreased up to 40% with single 100-mg to 200-mg doses and up to 70% with single 400 to 800-mg doses. Plasma aldosterone returned to baseline within 16 h after single 100-mg doses and multiple once-daily 120-mg doses. Lorundrostat demonstrated a favorable safety profile in healthy participants. Dose- and exposure-dependent inhibition of renal tubular sodium reabsorption was observed across a clinically relevant dose range with no suppression of basal or cosyntropin-stimulated cortisol production and only a modest increase in mean serum potassium.
Subject(s)
Aldosterone , Cytochrome P-450 CYP11B2 , Dose-Response Relationship, Drug , Humans , Cytochrome P-450 CYP11B2/antagonists & inhibitors , Male , Adult , Aldosterone/blood , Female , Middle Aged , Young Adult , Healthy Volunteers , Enzyme Inhibitors/pharmacokinetics , Enzyme Inhibitors/administration & dosage , Enzyme Inhibitors/pharmacology , Enzyme Inhibitors/adverse effects , Double-Blind Method , AdolescentABSTRACT
Bacteria are known to be constantly adapting to become resistant to antibiotics. Currently, efficient antibacterial compounds are still available; however, it is only a matter of time until these compounds also become inefficient. Ribonucleases are the enzymes responsible for the maturation and degradation of RNA molecules, and many of them are essential for microbial survival. Members of the PNPase and RNase II families of exoribonucleases have been implicated in virulence in many pathogens and, as such, are valid targets for the development of new antibacterials. In this paper, we describe the use of virtual high-throughput screening (vHTS) to identify chemical compounds predicted to bind to the active sites within the known structures of RNase II and PNPase from Escherichia coli. The subsequent in vitro screening identified compounds that inhibited the activity of these exoribonucleases, with some also affecting cell viability, thereby providing proof of principle for utilizing the known structures of these enzymes in the pursuit of new antibacterials.
Subject(s)
Anti-Bacterial Agents , Enzyme Inhibitors , Escherichia coli , Exoribonucleases , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Exoribonucleases/antagonists & inhibitors , Exoribonucleases/metabolism , Enzyme Inhibitors/pharmacology , Enzyme Inhibitors/chemistry , Escherichia coli/drug effects , Escherichia coli/enzymology , Catalytic Domain , High-Throughput Screening Assays/methods , Escherichia coli Proteins/metabolism , Escherichia coli Proteins/antagonists & inhibitors , Bacteria/drug effects , Bacteria/enzymologyABSTRACT
Nitric oxide (NO) has been defined as the "miracle molecule" due to its essential pleiotropic role in living systems. Besides its implications in physiologic functions, it is also involved in the development of several disease states, and understanding this ambivalence is crucial for medicinal chemists to develop therapeutic strategies that regulate NO production without compromising its beneficial functions in cell physiology. Although nitric oxide synthase (NOS), i.e., the enzyme deputed to the NO biosynthesis, is a well-recognized druggable target to regulate NO bioavailability, some issues have emerged during the past decades, limiting the progress of NOS modulators in clinical trials. In the present review, we discuss the most promising advancements in the research of small molecules that are able to regulate NOS activity with improved pharmacodynamic and pharmacokinetic profiles, providing an updated framework of this research field that could be useful for the design and development of new NOS modulators.