RESUMEN
Platensilin, platensimycin, and platencin are potent inhibitors of ß-ketoacyl-acyl carrier protein synthase (FabF) in the bacterial and mammalian fatty acid synthesis system, presenting promising drug leads for both antibacterial and antidiabetic therapies. Herein, a bioinspired skeleton reconstruction approach is reported, which enables the unified synthesis of these three natural FabF inhibitors and their skeletally diverse analogs, all stemming from a common ent-pimarane core. The synthesis features a diastereoselective biocatalytic reduction and an intermolecular Diels-Alder reaction to prepare the common ent-pimarane core. From this intermediate, stereoselective Mn-catalyzed hydrogen atom-transfer hydrogenation and subsequent Cu-catalyzed carbenoid C-H insertion afford platensilin. Furthermore, the intramolecular Diels-Alder reaction succeeded by regioselective ring opening of the newly formed cyclopropane enables the construction of the bicyclo[3.2.1]-octane and bicyclo[2.2.2]-octane ring systems of platensimycin and platencin, respectively. This skeletal reconstruction approach of the ent-pimarane core facilitates the preparation of analogs bearing different polycyclic scaffolds. Among these analogs, the previously unexplored cyclopropyl analog 47 exhibits improved antibacterial activity (MIC80 = 0.0625 µg/mL) against S. aureus compared to platensimycin.
Asunto(s)
Adamantano , Aminobenzoatos , Aminofenoles , Anilidas , Compuestos Policíclicos , Aminofenoles/química , Aminofenoles/farmacología , Aminofenoles/síntesis química , Compuestos Policíclicos/química , Compuestos Policíclicos/farmacología , Compuestos Policíclicos/síntesis química , Adamantano/química , Adamantano/farmacología , Adamantano/síntesis química , Adamantano/análogos & derivados , Anilidas/farmacología , Anilidas/química , Anilidas/síntesis química , Aminobenzoatos/farmacología , Aminobenzoatos/química , Aminobenzoatos/síntesis química , Antibacterianos/farmacología , Antibacterianos/síntesis química , Antibacterianos/química , Staphylococcus aureus/efectos de los fármacos , Estructura Molecular , Reacción de Cicloadición , Pruebas de Sensibilidad Microbiana , Estereoisomerismo , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/químicaRESUMEN
Interfering with sterol biosynthesis is an important strategy for developing safe and effective antifungal drugs. We previously identified compound H55 as an allosteric inhibitor of the fungal-specific C-24 sterol methyltransferase Erg6 for treating Candida albicans infections. Herein, 62 derivatives of H55 were designed and synthesized based on target-ligand interactions to identify more active candidates. Among them, d28 displayed the most potent antivirulence ability (MHIC50 = 0.25 µg/mL) by targeting Erg6, exhibiting an 8-fold increase in potency compared with H55. Moreover, d28 significantly outperformed H55 in inhibiting cell adhesion and biofilm formation, and exhibited minimal cytotoxicity and negligible potential to induce drug resistance. Of note, the coadministration of d28 and other sterol biosynthesis inhibitors, such as tridemorph or terbinafine, demonstrated a strong synergistic antifungal action in vitro and in vivo in a murine skin infection model. These results support the potential application of d28 in the treatment of C. albicans infections.
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Antifúngicos , Candida albicans , Candidiasis , Metiltransferasas , Candida albicans/efectos de los fármacos , Antifúngicos/farmacología , Antifúngicos/síntesis química , Antifúngicos/química , Antifúngicos/uso terapéutico , Animales , Relación Estructura-Actividad , Ratones , Candidiasis/tratamiento farmacológico , Metiltransferasas/antagonistas & inhibidores , Metiltransferasas/metabolismo , Pruebas de Sensibilidad Microbiana , Biopelículas/efectos de los fármacos , Humanos , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/uso terapéutico , FemeninoRESUMEN
Four new monomeric sorbicillinoids, trichillinoids A - D (1-4), along with two known dimeric sorbicillinoids (5 and 6), and five known monomeric sorbicillinoids (7-11), were obtained from the marine-fish-derived fungus Trichoderma sp. G13. They were structurally characterized on the basis of comprehensive spectroscopic investigations (NMR, HRESIMS, and ECD). Compounds 1-4 displayed moderate anti-inflammatory activities, according to inhibiting the production of NO in RAW264.7 cells activated with IC50 values ranging from 14 to 20 µM.
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Antiinflamatorios , Trichoderma , Ratones , Animales , Células RAW 264.7 , Estructura Molecular , Antiinflamatorios/farmacología , Antiinflamatorios/aislamiento & purificación , Trichoderma/química , Óxido Nítrico/metabolismo , Peces/microbiología , ChinaRESUMEN
Three isocoumarins, ascoisocoumarin A (1), embeurekol (2), and sclerotinin A (3), and five biosynthetically related derivatives, ascospinols A-C (4, 6, and 7), and talaflavuols C and B (5 and 8), together with twelve polyketides or terpenes (9-20) were isolated from the fungus Aspergillus sp. LY-1-2 inhabited in a sample of Cordyceps sp. Most of them belong to the family of oxygen-containing aromatic compounds and compounds 1, 4, 6, and 7 are previously undescribed compounds. Their planar structures were established by a combined spectroscopic analysis of HRESIMS and NMR, and their stereochemistry was determined by 13C NMR calculations with sorted training set (STS) protocol analysis, and ECD calculations. New compounds 1 and 6 displayed potential anti-inflammatory effects in lipopolysaccharide (LPS)-induced BV2 microglia cells.
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The global expansion of rapeseed seed quality has been focused on maintaining glucosinolate (GSL) and erucic acid (EA) contents. However, the influence of seed GSL and EA contents on the germination process under drought stress remains poorly understood. Herein, 114 rapeseed accessions were divided into four groups based on GSL and EA contents to investigate their performance during seed imbibition under drought stress. Our results revealed significant variations in seed germination-related traits, particularly with higher GSL and EA, which exhibited higher germination % (G%) and lower mean germination time (MGT) under drought stress conditions. Moreover, osmoregulation, enzymatic system and hormonal regulation were improved in high GSL and high EA (HGHE) versus low GSL and low EA (LGLE) seeds, indicating the essential protective role of GSL and EA during the germination process in response to drought stress. The transcriptional regulation mechanism for coordinating GSL-EA-related pathways in response to drought stress during seed imbibition was found to involve the differential expression of sugar metabolism-, antioxidant-, and hormone-related genes with higher enrichment in HGHE compared to LGLE seeds. GO enrichment analysis showed higher variations in transcription regulator activity and DNA-binding transcription factors, as well as ATP and microtubule motor activity in GSL-EA-related pathways. Furthermore, KEGG analysis identified cellular processes, environmental information processing, and metabolism categories, with varied gene participation between GSL, EA and GSL-EA-related pathways. For further clarification, QY7 (LGLE) seeds were primed with different concentrations of GSL and EA under drought stress conditions. The results showed that 200 µmol/L of GSL and 400 µmol/L of EA significantly improved G%, MGT, and seedling fresh weight, besides regulating stress and fatty acid responsive genes during the seed germination process under drought stress conditions. Conclusively, exogenous application of GSL and EA is considered a promising method for enhancing the drought tolerance of LGLE seeds. Furthermore, the current investigation could provide a theoretical basis of GSL and EA roles and their underlying mechanisms in stress tolerance during the germination process.
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Brassica napus , Brassica rapa , Ácidos Erucicos , Germinación/genética , Brassica napus/genética , Glucosinolatos/metabolismo , Sequías , Semillas/genética , Semillas/metabolismo , Brassica rapa/genética , Perfilación de la Expresión GénicaRESUMEN
Lichens are some of the most unique fungi and are naturally encountered as symbiotic biological organisms that usually consist of fungal partners (mycobionts) and photosynthetic organisms (green algae and cyanobacteria). Due to their distinctive growth environments, including hot deserts, rocky coasts, Arctic tundra, toxic slag piles, etc., they produce a variety of biologically meaningful and structurally novel secondary metabolites to resist external environmental stresses. The endofungi that live in and coevolve with lichens can also generate abundant secondary metabolites with novel structures, diverse skeletons, and intriguing bioactivities due to their mutualistic symbiosis with hosts, and they have been considered as strategically significant medicinal microresources for the discovery of pharmaceutical lead compounds in the medicinal industry. They are also of great importance in the fundamental research field of natural product chemistry. In this work, we conducted a comprehensive review and systematic evaluation of the secondary metabolites of endolichenic fungi regarding their origin, distribution, structural characteristics, and biological activity, as well as recent advances in their medicinal applications, by summarizing research achievements since 2015. Moreover, the current research status and future research trends regarding their chemical components are discussed and predicted. A systematic review covering the fundamental chemical research advances and pharmaceutical potential of the secondary metabolites from endolichenic fungi is urgently required to facilitate our better understanding, and this review could also serve as a critical reference to provide valuable insights for the future research and promotion of natural products from endolichenic fungi.
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Seven new terpenoids, including six sacculatane diterpenoids plagiochilarins A-F (1-6), and one ent-2,3-seco-aromandrane sesquiterpenoid plagiochilarin H (8) with a 6/7/3/5 tetracyclic scaffold, alongside three known compounds, were obtained from the Chinese liverwort Plagiochila nitens Inoue. Plagiochilarin B (2) was unpredictably converted to the more stable artifact 7 under acid catalysis through cyclic ether formation. The reaction mechanism was reasonably deduced and experimentally verified. The structures of these terpenoids were determined by analysis of MS and NMR spectroscopic data and single-crystal X-ray diffraction. The inhibitory effect of all of the isolates was evaluated on the growth of two C. albicans strains, wild strain SC5314 and efflux pump-deficient strain DSY654. However, only plagiochilarin H (8) showed a MIC value of 16 µg/mL against C. albicans DSY654.
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Candida albicans , Diterpenos , Hepatophyta , Hepatophyta/química , Diterpenos/química , Diterpenos/farmacología , Diterpenos/aislamiento & purificación , China , Candida albicans/efectos de los fármacos , Estructura Molecular , Pruebas de Sensibilidad Microbiana , Antifúngicos/farmacología , Antifúngicos/química , Cristalografía por Rayos XRESUMEN
As a model liverwort, Marchantia polymorpha contains various flavone glucuronides with cardiovascular-promoting effects and anti-inflammatory properties. However, the related glucuronosyltransferases have not yet been reported. In this study, two bifunctional UDP-glucuronic acid/UDP-glucose:flavonoid glucuronosyltransferases/glucosyltransferases, MpUGT742A1 and MpUGT736B1, were identified from M. polymorpha. Extensive enzymatic assays found that MpUGT742A1 and MpUGT736B1 exhibited efficient glucuronidation activity for flavones, flavonols, and flavanones and showed promiscuous regioselectivity at positions 3, 6, 7, 3', and 4'. These enzymes catalyzed the production of a variety of flavonoid glucuronides with medicinal value, including apigenin-7-O-glucuronide and scutellarein-7-O-glucuronide. With the use of MpUGT736B1, apigenin-4'-O-glucuronide and apigenin-7,4'-di-O-glucuronide were prepared by scaled-up enzymatic catalysis and structurally identified by NMR spectroscopy. MpUGT742A1 also displayed glucosyltransferase activity on the 7-OH position of the flavanones using UDP-glucose as the sugar donor. Furthermore, we constructed four recombinant strains by combining the pathway for increasing the UDP-glucuronic acid supply with the two novel UGTs MpUGT742A1 and MpUGT736B1. When apigenin was used as a substrate, the extracellular apigenin-4'-O-glucuronide and apigenin-7,4'-di-O-glucuronide production obtained from the Escherichia coli strain BB2 reached 598 and 81 mg/L, respectively. Our study provides new candidate genes and strategies for the biosynthesis of flavonoid glucuronides.
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Flavanonas , Marchantia , Flavonoides/química , Apigenina , Glucurónidos/metabolismo , Marchantia/metabolismo , Glucuronosiltransferasa/química , Glucuronosiltransferasa/metabolismo , Escherichia coli/metabolismo , Glucosa , Ácido Glucurónico , Uridina DifosfatoRESUMEN
Infertility is a major reproductive health problem. Approximately 50% of all documented cases of infertility are attributable to male factors, such as poor testicular function and semen quality. The recent significant global decline in sperm counts has serious implications for male fertility, but the armamentarium for improving testicular function and semen quality is limited. Natural products have a wide range of activities and are a major source of drugs for disease prevention and treatment. To provide ideas and a theoretical basis for the research and development of therapeutic drugs for male infertility, this review summarizes natural products (mostly monomers) that have been shown to improve testicular function and semen quality and their possible mechanisms of action. These natural products primarily improve testicular function and semen quality via antioxidant, antiapoptotic, and anti-inflammatory effects, in addition to increasing serum testosterone and reducing DNA damage in spermatozoa and testicular cells. Prospects for the application of natural products in the treatment of male infertility are discussed.
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Productos Biológicos , Infertilidad Masculina , Masculino , Humanos , Infertilidad Masculina/tratamiento farmacológico , Productos Biológicos/uso terapéutico , Testículo/efectos de los fármacos , Testículo/metabolismo , Animales , Análisis de Semen , Espermatozoides/efectos de los fármacosRESUMEN
Phenylpropanoids play important roles in plant physiology and the enzyme 4-coumarate: coenzyme A ligase (4CL) catalyzes the formation of thioesters. Despite extensive characterization in various plants, the functions of 4CLs in the liverwort Marchantia paleacea remain unknown. Here, four 4CLs from M. paleacea were isolated and functionally analyzed. Heterologous expression in Escherichia coli indicated the presence of different enzymatic activities in the four enzymes. Mp4CL1 and Mp4CL2 were able to convert caffeic, p-coumaric, cinnamic, ferulic, dihydro-p-coumaric, and 5-hydroxyferulic acids to their corresponding CoA esters, while Mp4CL3 and Mp4CL4 catalyzed none. Mp4CL1 transcription was induced when M. paleacea thalli were treated with methyl jasmonate (MeJA). The overexpression of Mp4CL1 increased the levels of lignin in transgenic Arabidopsis. In addition, we reconstructed the flavanone biosynthetic pathway in E. coli. The pathway comprised Mp4CL1, co-expressed with chalcone synthase (CHS) from different plant species, and the efficiency of biosynthesis was optimal when both the 4CL and CHS were obtained from the same species M. paleacea.
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Arabidopsis , Flavanonas , Marchantia , Ligasas , Marchantia/genética , Lignina , Escherichia coli/genética , Clonación MolecularRESUMEN
Oligomycins are potent antifungal and antitumor agents. Mass spectrometry (MS)- and nuclear magnetic resonance (NMR)-based metabolomic fingerprinting analysis of marine-derived actinomycetes in our in-house library provided an oligomycin-producing strain, Streptomyces sp. FXY-T5. Chemical investigation led to the discovery of five new oligomycins, 24-lumooligomycin B (1), 4-lumooligomycin B (2), 6-lumooligomycin B (3), 40-homooligomycin B (4), and 15-hydroxy-oligomycin B (5), together with seven biosynthetically related known derivatives. Their structures were assigned by MS, NMR, electronic circular dichroism (ECD), and single-crystal X-ray diffraction analyses. The biosynthesis pathway of oligomycins was first proposed based on the analysis of a type I modular polyketide synthase (PKS) system and targeted gene disruption. As expected, the isolated oligomycins showed significant antiagricultural fungal pathogen activity and antiproliferative properties from which the possible structure-activity relationships were first suggested. More importantly, oligomycins induced significant G1-phase cell cycle arrest on cancer cells and significantly attenuated their Cyclin D1 and PCNA expression through a ß-catenin signaling pathway.
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Antineoplásicos , Streptomyces , Streptomyces/química , Oligomicinas/farmacología , Oligomicinas/química , Antineoplásicos/farmacología , Antineoplásicos/metabolismo , Relación Estructura-Actividad , Antifúngicos/farmacologíaRESUMEN
Triptolide has a significant antitumor activity, but its toxicity limits its clinical application. As the mitochondrion-targeting strategy showed an advantage in selective antitumor effect based on the higher mitochondrial membrane potential (MMP) in tumor cells than normal cells, the lipophilic cations triphenylphosphonium and E-4-(1H-indol-3-yl vinyl)-N-methylpyridinium iodide (F16) were selected as targeting carriers for structural modification of triptolide. The derivatives bearing F16 generally retained most antitumor activities, overcame its inhibition plateau phenomena, and enhanced its selective antitumor effect in lung cancer. The representative derivative F9 could accumulate in the mitochondria of NCI-H1975 cells, inducing apoptosis and a dose-dependent increase in intracellular reactive oxygen species and reducing MMP. Moreover, no effects were observed in normal cells BEAS-2B. In vivo studies showed that the developmental, renal, and liver toxicities of F9 to zebrafish were significantly lower than those of triptolide. This study provides a promising idea to relieve the toxicity problem of triptolide.
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Diterpenos , Compuestos Organofosforados , Fenantrenos , Animales , Pez Cebra , Mitocondrias , Apoptosis , Diterpenos/toxicidad , Diterpenos/química , Fenantrenos/toxicidad , Fenantrenos/química , Línea Celular Tumoral , Compuestos EpoxiRESUMEN
Mitochondria, responsible for ATP production and apoptosis regulation, play a key role in cancer cells. Honokiol regulates apoptosis through the endogenous mitochondrial pathway but does not specifically target tumor cells. We designed 28 novel derivatives of honokiol using triple-function delocalized lipophilic cations such as berberine and F16 as mitochondrion-targeting carriers. While all derivatives exhibited enhanced cytotoxicity toward tumor cells compared to honokiol, the derivative 2E-3-F16 exhibited a substantial tumor cell selectivity between NCI-H446 cancer cells and HBE cells by one order of magnitude and enhanced the sensitivity of A549 cells to cisplatin. Mechanistically, it targeted mitochondria and induced apoptosis by preventing tumor cells from entering the G0/G1 phases as well as inducing an abnormal elevation of reactive oxygen species, thereby decreasing the mitochondrial membrane potential level. It also showed lower toxicity toward Caenorhabditis elegans than honokiol. This study provides a possible method for developing mitochondrion-targeting antitumor drugs with high efficiency and low toxicity based on natural products.
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Antineoplásicos , Lignanos , Animales , Caenorhabditis elegans , Antineoplásicos/farmacología , Apoptosis , Lignanos/farmacología , Compuestos de Bifenilo/farmacología , Línea Celular TumoralRESUMEN
Mylnudones A-G (1-7), unprecedented 1,10-seco-aromadendrane-benzoquinone-type heterodimers, and a highly rearranged aromadendrane-type sesquiterpenoid (8), along with four known analogs (9-12), were isolated from the liverwort Mylia nuda. Compounds 1-6 and 7, bearing tricyclo[6.2.1.02,7] undecane and tricyclo[5.3.1.02,6] undecane backbones, likely formed via a Diels-Alder reaction and radical cyclization, respectively. Their structures were determined by spectroscopic analysis, computational calculation, and single-crystal X-ray diffraction analysis. Dimeric compounds displayed cytoprotective effects against glutamic acid-induced neurological deficits.
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Alcanos , Hepatophyta , Sesquiterpenos de Guayano , Sesquiterpenos , Hepatophyta/química , Estructura Molecular , Sesquiterpenos/farmacología , Sesquiterpenos/química , ChinaRESUMEN
Liverworts provide valuable ecological services to improve the sustainability of agriculture, encompassing soil health maintenance and natural pest management. Some liverworts have potential applications in medicine and as food additives. Twenty-two novel diterpenoids (anajoerins A-V), of which anajoerins B-G are rearranged labdanes featuring an unprecedented 6/5 fused ring system, were isolated from the Chinese liverwort Anastrophyllum joergensenii Schiffn. The absolute configurations of all compounds were identified based on high-resolution electrospray ionization mass spectroscopy data, NMR spectra, and ECD calculations. Plausible biogenetic pathways for unprecedented rearranged labdanes were proposed. Seven diterpenoids exhibited anti-inflammatory activity by reducing nitric oxide production in LPS-stimulated RAW264.7 murine macrophages in a dose-dependent manner with IC50s between 9.71 and 56.56 µM. All tested compounds showed no cytotoxicity at the tested concentrations. Western blot analyses of NF-κB p65 downregulation showed that anajoerin L could inhibit the NF-κB signaling pathway. Furthermore, anajoerin L also suppressed the secretion of the ConA-induced proinflammatory cytokines IFN-γ, TNF-α, and IL-6.
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Diterpenos , Hepatophyta , Animales , Ratones , FN-kappa B/metabolismo , Hepatophyta/metabolismo , Células RAW 264.7 , Antiinflamatorios/farmacología , Citocinas/metabolismo , China , Lipopolisacáridos/farmacología , Óxido Nítrico/metabolismoRESUMEN
Fungal infections present a growing global public health concern, necessitating the development of novel antifungal drugs. However, many potential antifungals, particularly the expelled potential active agents (EPAAs), are often underestimated owing to their limitations in cellular entry or expulsion by efflux pumps. Herein, we identified 68 EPAAs out of 2322 candidates with activity against a Candida albicans efflux pump-deficient strain and no inhibitory activity against the wild-type strain. Using a novel conjugation strategy involving benzamidine (BM) as a mitochondrion-targeting warhead, we successfully converted EPAAs into potent antifungals against various urgent-threat azole-resistantCandida strains. Among the obtained EPAA-BM conjugates, IS-2-BM (11) exhibited excellent antifungal activities and induced negligible drug resistance. Furthermore, IS-2-BM prevented biofilm formation, eradicated mature biofilms, and exhibited excellent therapeutic effects in a murine model of systemic candidiasis. These findings provide a promising strategy for increasing the possibilities of discovering more antifungals.
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Candidiasis , Micosis , Animales , Ratones , Humanos , Antifúngicos/farmacología , Antifúngicos/uso terapéutico , Candidiasis/tratamiento farmacológico , Candidiasis/microbiología , Candida albicans , Micosis/tratamiento farmacológico , Biopelículas , Pruebas de Sensibilidad Microbiana , Farmacorresistencia FúngicaRESUMEN
Nitrogen is one of the most essential macronutrients for plant growth and its availability in soil is vital for agricultural sustainability and productivity. However, excessive nitrogen application could reduce the nitrogen use efficiency and produce environmental pollution. Here, we systematically determined the response in lipidome and metabolome in rapeseed during nitrogen starvation. Plant growth was severely retarded during nitrogen deficiency, while the levels of most amino acids was significantly decreased. The levels of monogalactosyl diacyglycerol (MGDG) in leaves and roots was significantly decreased, while the level of digalactosyl diacylglycerol (DGDG) was significantly decreased in roots, resulting in significant reduction of MGDG/DGDG ratio during nitrogen starvation. Meanwhile, the levels of sulfoquinovosyl diacylglycerol, phosphatidylglycerol and glucuronosyl diacylglycerol was reduced to varying extents. Moreover, the levels of metabolites in the tricarboxylic acid cycle, Calvin cycle, and energy metabolism was changed during nitrogen deficiency. These findings show that nitrogen deprivation alters the membrane lipid metabolism and carbon metabolism, and our study provides valuable information to further understand the response of rapeseed to nitrogen deficiency at metabolism level.
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Shading significantly affects rapeseed yield, while reasonable nitrogen (N) application has efficiency gains. However, the functions and mechanisms of N are not fully established for shaded rapeseed plants. Therefore, we conducted a 2-year field experiment to study the effect of N on pod wall morphology and carbon metabolism of shaded rapeseed. Two varieties, three N rates (120 [N1], 240 [N2], and 360 [N3] kg hm-2 ) and two light intensities (100 and 70% light transmission) from 10 to 35 days after the end of flowering were set as experimental parameters. Shading decreased the pod wall chlorophyll content, ribulose 1,5-bisphosphate carboxylase (Rubisco) activity and glucose content at 25 and 35 days after flowering (DAF). Decreased sucrose synthase (SuSy) and sucrose phosphate synthase activity caused by shading reduced sucrose and fructose content. They are responsible for the decline in the 1000-seed weight and a 22.1-37.6% decline in seed yield. More N under shading promoted pod elongation and pigment content, improved chloroplast ultrastructure, increased Rubisco and SuSy activity at 35 DAF, thus contributing to pod wall photosynthesis and fructose and glucose levels in shaded rapeseed plants. Similar trends were observed in pod number, pod weight, and seed weight, while the greatest increase in seed/wall ratio was observed under N2 for shaded rapeseed plants. The results indicated that N can reduce the yield difference between different light conditions and balance partitioning and conversion of photoassimilates in pod wall, but avoid applying an excessive amount of nitrogen.