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1.
Antonie Van Leeuwenhoek ; 117(1): 26, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38261060

RESUMO

An appealing strategy for finding novel bioactive molecules in Nature consists in exploring underrepresented and -studied microorganisms. Here, we investigated the antimicrobial and tumoral anti-proliferative bioactivities of twenty-three marine and estuarine bacteria of the fascinating phylum Planctomycetota. This was achieved through extraction of compounds produced by the Planctomycetota cultured in oligotrophic medium followed by an antimicrobial screening against ten relevant human pathogens including Gram-positive and Gram-negative bacteria, and fungi. Cytotoxic effects of the extracts were also evaluated against five tumoral cell lines. Moderate to potent activities were obtained against Enterococcus faecalis, methicillin-sensitive and methicillin-resistant Staphylococcus aureus and vancomycin-sensitive and vancomycin-resistant Enterococcus faecium. Anti-fungal effects were observed against Trichophyton rubrum, Candida albicans and Aspergillus fumigatus. The highest cytotoxic effects were observed against human breast, pancreas and melanoma tumoral cell lines. Novipirellula caenicola and Rhodopirellula spp. strains displayed the widest spectrum of bioactivities while Rubinisphaera margarita ICM_H10T affected all Gram-positive bacteria tested. LC-HRMS analysis of the extracts did not reveal the presence of any known bioactive natural product, suggesting that the observed activities are most likely caused by novel molecules, that need identification. In summary, we expanded the scope of planctomycetal species investigated for bioactivities and demonstrated that various strains are promising sources of novel bioactive compounds, which reenforces the potential biotechnological prospects offered by Planctomycetota.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Planctomicetos , Humanos , Bactérias Gram-Negativas , Antibacterianos/farmacologia , Vancomicina , Bactérias Gram-Positivas
2.
Molecules ; 29(2)2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38257340

RESUMO

Cancer is one of the leading causes of death worldwide, with breast cancer being the second cause of cancer-related mortality among women. Natural Products (NPs) are one of the main sources for drug discovery. During a screening campaign focused on the identification of extracts from Fundación MEDINA's library inhibiting the proliferation of cancer cell lines, a significant bioactivity was observed in extracts from cultures of the fungus Angustimassarina populi CF-097565. Bioassay-guided fractionation of this extract led to the identification and isolation of herbarin (1), 1-hydroxydehydroherbarin (4) plus other three naphthoquinone derivatives of which 3 and 5 are new natural products and 2 is herein described from a natural source for the first time. Four of these compounds (1, 3, 4 and 5) confirmed a specific cytotoxic effect against the human breast cancer cell line MCF-7. To evaluate the therapeutic potential of the compounds isolated, their efficacy was validated in 3D cultures, a cancer model of higher functionality. Additionally, an in-depth study was carried out to test the effect of the compounds in terms of cell mortality, sphere disaggregation, shrinkage, and morphology. The cell profile of the compounds was also compared to that of known cytotoxic compounds with the aim to distinguish the drug mode of action (MoA). The profiles of 1, 3 and 4 showed more biosimilarity between them, different to 5, and even more different to other known cytotoxic agents, suggesting an alternative MoA responsible for their cytotoxicity in 3D cultures.


Assuntos
Ascomicetos , Medicamentos Biossimilares , Neoplasias da Mama , Feminino , Humanos , Neoplasias da Mama/tratamento farmacológico , Bioensaio
3.
Mar Drugs ; 21(8)2023 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-37623724

RESUMO

Antimicrobial resistance can be considered a hidden global pandemic and research must be reinforced for the discovery of new antibiotics. The spirotetronate class of polyketides, with more than 100 bioactive compounds described to date, has recently grown with the discovery of phocoenamicins, compounds displaying different antibiotic activities. Three marine Micromonospora strains (CA-214671, CA-214658 and CA-218877), identified as phocoenamicins producers, were chosen to scale up their production and LC/HRMS analyses proved that EtOAc extracts from their culture broths produce several structurally related compounds not disclosed before. Herein, we report the production, isolation and structural elucidation of two new phocoenamicins, phocoenamicins D and E (1-2), along with the known phocoenamicin, phocoenamicins B and C (3-5), as well as maklamicin (7) and maklamicin B (6), the latter being reported for the first time as a natural product. All the isolated compounds were tested against various human pathogens and revealed diverse strong to negligible activity against methicillin-resistant Staphylococcus aureus, Mycobacterium tuberculosis H37Ra, Enterococcus faecium and Enterococcus faecalis. Their cell viability was also evaluated against the human liver adenocarcinoma cell line (Hep G2), demonstrating weak or no cytotoxicity. Lastly, the safety of the major compounds obtained, phocoenamicin (3), phocoenamicin B (4) and maklamicin (7), was tested against zebrafish eleuthero embryos and all of them displayed no toxicity up to a concentration of 25 µM.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Micromonospora , Humanos , Animais , Peixe-Zebra , Macrolídeos/farmacologia , Antibacterianos/farmacologia
4.
Mar Drugs ; 21(12)2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-38132955

RESUMO

The fungal strain BC17 was isolated from sediments collected in the intertidal zone of the inner Bay of Cadiz and characterized as Emericellopsis maritima. On the basis of the one strain-many compounds (OSMAC) approach, four new eremophilane-type sesquiterpenes (1-4), together with thirteen known derivatives (5-17) and two reported diketopiperazines (18, 19), were isolated from this strain. The chemical structures and absolute configurations of the new compounds were determined through extensive NMR and HRESIMS spectroscopic studies and ECD calculation. Thirteen of the isolated eremophilanes were examined for cytotoxic and antimicrobial activities. PR toxin (16) exhibited cytotoxic activity against HepG2, MCF-7, A549, A2058, and Mia PaCa-2 human cancer cell lines with IC50 values ranging from 3.75 to 33.44 µM. (+)-Aristolochene (10) exhibited selective activity against the fungal strains Aspergillus fumigatus ATCC46645 and Candida albicans ATCC64124 at 471 µM.


Assuntos
Anti-Infecciosos , Antineoplásicos , Hypocreales , Sesquiterpenos , Humanos , Sesquiterpenos Policíclicos , Sesquiterpenos/química , Antineoplásicos/química , Sedimentos Geológicos/microbiologia , Anti-Infecciosos/química , Estrutura Molecular
5.
Org Biomol Chem ; 20(5): 1031-1040, 2022 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-35018938

RESUMO

An abundant sponge of the order Bubarida was selected for further chemical investigation following biological and chemical screening of sponges collected from Futuna Islands in the Indo-Pacific. Ten new nitrogenous bisabolene derivatives were isolated and identified: the monomeric theonellin formamide analogues named bubaridins A-F (1-6) with unusual oxidised linear chains, and the first isocyanide/formamide dimeric and cyclised bisabolenes 7-9. The structure elucidation of these nitrogenous bisabolenes involved HRESIMS, NMR, and ECD analyses, and the chiral compounds were found to be racemates. A biosynthetic hypothesis for the production of these metabolites is proposed and some chemotaxonomic considerations are discussed. Furthermore, the antimicrobial and antitumoral activity were evalutated and the trans-dimer theonellin isocyanide (7) was shown to exhibit potent and selective antifungal activity.


Assuntos
Antifúngicos/farmacologia , Cicloexilaminas/farmacologia , Sesquiterpenos Monocíclicos/farmacologia , Poríferos/química , Animais , Antifúngicos/química , Antifúngicos/isolamento & purificação , Candida/efeitos dos fármacos , Linhagem Celular Tumoral , Cicloexilaminas/síntese química , Cicloexilaminas/isolamento & purificação , Humanos , Ilhas , Testes de Sensibilidade Microbiana , Estrutura Molecular , Sesquiterpenos Monocíclicos/química , Sesquiterpenos Monocíclicos/isolamento & purificação , Oceano Pacífico
6.
J Nat Prod ; 85(1): 25-33, 2022 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-35045259

RESUMO

The number of species in Aspergillus section Flavi has recently increased to 36 and includes some of the most important and well-known species in the genus Aspergillus. Numerous secondary metabolites, especially mycotoxins, have been reported from species such as A. flavus; however many of the more recently described species are less studied from a chemical point of view. This paper describes the use of MS/MS-based molecular networking to investigate the metabolome of A. caelatus leading to the discovery of several new diketopiperazine dimers and aspergillicins. An MS-guided isolation procedure yielded six new compounds, including asperazines D-H (1-5) and aspergillicin H (6). Asperazines G and H are artifacts derived from asperazines E and F formed during the separation process by formic acid. Two known compounds, aspergillicins A and C (7 and 8), were isolated from the same strain. Structures were elucidated by analyzing their HR-MS/MS and NMR spectroscopic data. The absolute configuration of asperazines D-F and aspergillicin H were deduced from the combination of NMR, Marfey's method, and ECD analyses.


Assuntos
Aspergillus/química , Depsipeptídeos/química , Dicetopiperazinas/química , Dimerização , Micotoxinas/química , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Espectroscopia de Prótons por Ressonância Magnética , Espectrometria de Massas em Tandem
7.
Molecules ; 27(19)2022 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-36234892

RESUMO

Current needs in finding new antibiotics against emerging multidrug-resistant superbugs are pushing the scientific community into coming back to Nature for the discovery of novel active structures. Recently, a survey of halophilic actinomyectes from saline substrates of El Saladar del Margen, in the Cúllar-Baza depression (Granada, Spain), led us to the isolation and identification of 108 strains from the rhizosphere of the endemic plant Limonium majus. Evaluation of the potential of these strains to produce new anti-infective agents against superbug pathogens was performed through fermentation in 10 different culture media using an OSMAC approach and assessment of the antibacterial and antifungal properties of their acetone extracts. The study allowed the isolation of two novel antibiotic compounds, kribbellichelin A (1) and B (2), along with the known metabolites sandramycin (3), coproporphyrin III (4), and kribelloside C (5) from a bioassay-guided fractionation of scaled-up active extracts of the Kribbella sp. CA-293567 strain. The structures of the new molecules were elucidated by ESI-qTOF-MS/MS, 1D and 2D NMR, and Marfey's analysis for the determination of the absolute configuration of their amino acid residues. Compounds 1-3 and 5 were assayed against a panel of relevant antibiotic-resistant pathogenic strains and evaluated for cytotoxicity versus the human hepatoma cell line HepG2 (ATCC HB-8065). Kribbellichelins A (1) and B (2) showed antimicrobial activity versus Candida albicans ATCC-64124, weak potency against Acinetobacter baumannii MB-5973 and Pseudomonas aeruginosa MB-5919, and an atypical dose-dependent concentration profile against Aspergillus fumigatus ATCC-46645. Sandramycin (3) confirmed previously reported excellent growth inhibition activity against MRSA MB-5393 but also presented clear antifungal activity against C. albicans ATCC-64124 and A. fumigatus ATCC-46645 associated with lower cytotoxicity observed in HepG2, whereas Kribelloside C (5) displayed high antifungal activity only against A. fumigatus ATCC-46645. Herein, we describe the processes followed for the isolation, structure elucidation, and potency evaluation of these two new active compounds against a panel of human pathogens as well as, for the first time, the characterization of the antifungal activities of sandramycin (3).


Assuntos
Actinomycetales , Anti-Infecciosos , Acetona , Aminoácidos , Antibacterianos/química , Anti-Infecciosos/farmacologia , Antifúngicos/química , Candida albicans , Meios de Cultura , Humanos , Testes de Sensibilidade Microbiana , Espectrometria de Massas em Tandem
8.
Molecules ; 27(17)2022 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-36080182

RESUMO

Forkhead box O (FOXO) proteins are transcription factors involved in cancer and aging and their pharmacological manipulation could be beneficial for the treatment of cancer and healthy aging. FOXO proteins are mainly regulated by post-translational modifications including phosphorylation, acetylation and ubiquitination. As these modifications are reversible, activation and inactivation of FOXO factors is attainable through pharmacological treatment. One major regulatory input of FOXO signaling is mediated by protein kinases. Here, we use specific inhibitors against different kinases including PI3K, mTOR, MEK and ALK, and other receptor tyrosine kinases (RTKs) to determine their effect on FOXO3 activity. While we show that inhibition of PI3K efficiently drives FOXO3 into the cell nucleus, the dual PI3K/mTOR inhibitors dactolisib and PI-103 induce nuclear FOXO translocation more potently than the PI3Kδ inhibitor idelalisib. Furthermore, specific inhibition of mTOR kinase activity affecting both mTORC1 and mTORC2 potently induced nuclear translocation of FOXO3, while rapamycin, which specifically inhibits the mTORC1, failed to affect FOXO3. Interestingly, inhibition of the MAPK pathway had no effect on the localization of FOXO3 and upstream RTK inhibition only weakly induced nuclear FOXO3. We also measured the effect of the test compounds on the phosphorylation status of AKT, FOXO3 and ERK, on FOXO-dependent transcriptional activity and on the subcellular localization of other FOXO isoforms. We conclude that mTORC2 is the most important second layer kinase negatively regulating FOXO activity.


Assuntos
Fatores de Transcrição Forkhead , Serina-Treonina Quinases TOR , Proteína Forkhead Box O3/genética , Proteína Forkhead Box O3/metabolismo , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina , Alvo Mecanístico do Complexo 2 de Rapamicina , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo
9.
J Nat Prod ; 84(4): 979-985, 2021 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-33656895

RESUMO

Five new polyketides were isolated from the rare filamentous fungus Aspergillus californicus IBT 16748 including calidiol A (1); three phthalide derivatives califuranones A1, A2, and B (2-4); and a pair of enantiomers (-)-calitetralintriol A (-5) and (+)-calitetralintriol A (+5) together with four known metabolites (6-9). The structures of the new products were established by extensive spectroscopic analyses including HRMS and 1D and 2D NMR. The absolute configurations of two diastereomers 2 and 3 and the enantiomers (-5) and (+5) were assigned by comparing their experimental and calculated ECD data, whereas the absolute configuration of 4 was proposed by analogy. Compound 1 showed moderate activity against methicillin-resistant Staphylococcus aureus.


Assuntos
Antibacterianos/farmacologia , Aspergillus/química , Policetídeos/farmacologia , Antibacterianos/isolamento & purificação , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Policetídeos/isolamento & purificação
10.
Mar Drugs ; 19(2)2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-33573261

RESUMO

Marine sponges harbor diverse microbial communities that represent a significant source of natural products. In the present study, extracts of 21 sponge-associated bacteria were screened for their antimicrobial and anticancer activity, and their genomes were mined for secondary metabolite biosynthetic gene clusters (BGCs). Phylogenetic analysis assigned the strains to four major phyla in the sponge microbiome, namely Proteobacteria, Actinobacteria, Bacteroidetes, and Firmicutes. Bioassays identified one extract with anti-methicillin-resistant Staphylococcus aureus (MRSA) activity, and more than 70% of the total extracts had a moderate to high cytotoxicity. The most active extracts were derived from the Proteobacteria and Actinobacteria, prominent for producing bioactive substances. The strong bioactivity potential of the aforementioned strains was also evident in the abundance of BGCs, which encoded mainly beta-lactones, bacteriocins, non-ribosomal peptide synthetases (NRPS), terpenes, and siderophores. Gene-trait matching was performed for the most active strains, aiming at linking their biosynthetic potential with the experimental results. Genetic associations were established for the anti-MRSA and cytotoxic phenotypes based on the similarity of the detected BGCs with BGCs encoding natural products with known bioactivity. Overall, our study highlights the significance of combining in vitro and in silico approaches in the search of novel natural products of pharmaceutical interest.


Assuntos
Anti-Infecciosos/farmacologia , Antineoplásicos/farmacologia , Bactérias/metabolismo , Avaliação Pré-Clínica de Medicamentos , Família Multigênica , Poríferos/microbiologia , Animais , Bactérias/genética , Genoma Bacteriano , Filogenia
11.
Bioorg Med Chem Lett ; 30(6): 126952, 2020 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-32005414

RESUMO

In the course of a primary screening of 614 microbial actinomycete extracts for the discovery of tyrosinase inhibitors, the EtOAc extract of the fermentation broth of the strain Streptomyces sp. CA-129531 isolated from a Martinique sample, exhibited in cell free and cell-based assays the most promising activity (IC50 value of 63 µg/mL). Scaled-up production in a bioreactor led to the isolation of one new trichostatic acid analogue, namely trichostatic acid B (1), along with six known trichostatin derivatives (2-7), four diketopiperazines (8-11), two butyrolactones (12-13) and one hydroxamic acid siderophore (14). Among them, trichostatin A (4) showed a Ki value of 6.1 µM and six times stronger anti-tyrosinase activity (IC50 2.18 µΜ) than kojic acid (IC50 14.07 µΜ) used as a positive control. Deoxytrichostatin A (6) displayed also strong inhibitory activity against tyrosinase (IC50 19.18 µΜ). Trichostatin A production in bioreactor started together with the exponential phase of growth (day 4) and the maximum concentration was reached at day 9 (2.67 ± 0.13 µg/mL). Despite the cytotoxicity of some individual components, the EtOAc extract showed no cytotoxic effect on HepG2, A2058, A549, MCF-7 and MIA PaCa-2 cell lines, (IC50 >2.84 mg/mL) and against BG fibroblasts at the concentrations where the whitening effect was exerted, reassuring its safety and great tyrosinase inhibitory potential.


Assuntos
Actinobacteria/química , Misturas Complexas/química , Inibidores Enzimáticos/química , Ácidos Hidroxâmicos/química , Monofenol Mono-Oxigenase/antagonistas & inibidores , Streptomyces/química , Reatores Biológicos , Sobrevivência Celular/efeitos dos fármacos , Misturas Complexas/metabolismo , Dicetopiperazinas/química , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/metabolismo , Fermentação , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Humanos , Ácidos Hidroxâmicos/metabolismo , Lactonas/química , Programas de Rastreamento , Pironas/química , Metabolismo Secundário/efeitos dos fármacos
12.
Circulation ; 135(9): e122-e137, 2017 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-28126839

RESUMO

BACKGROUND: In 2008, the National Heart, Lung, and Blood Institute convened an Implementation Science Work Group to assess evidence-based strategies for effectively implementing clinical practice guidelines. This was part of a larger effort to update existing clinical practice guidelines on cholesterol, blood pressure, and overweight/obesity. OBJECTIVES: Review evidence from the published implementation science literature and identify effective or promising strategies to enhance the adoption and implementation of clinical practice guidelines. METHODS: This systematic review was conducted on 4 critical questions, each focusing on the adoption and effectiveness of 4 intervention strategies: (1) reminders, (2) educational outreach visits, (3) audit and feedback, and (4) provider incentives. A scoping review of the Rx for Change database of systematic reviews was used to identify promising guideline implementation interventions aimed at providers. Inclusion and exclusion criteria were developed a priori for each question, and the published literature was initially searched up to 2012, and then updated with a supplemental search to 2015. Two independent reviewers screened the returned citations to identify relevant reviews and rated the quality of each included review. RESULTS: Audit and feedback and educational outreach visits were generally effective in improving both process of care (15 of 21 reviews and 12 of 13 reviews, respectively) and clinical outcomes (7 of 12 reviews and 3 of 5 reviews, respectively). Provider incentives showed mixed effectiveness for improving both process of care (3 of 4 reviews) and clinical outcomes (3 reviews equally distributed between generally effective, mixed, and generally ineffective). Reminders showed mixed effectiveness for improving process of care outcomes (27 reviews with 11 mixed and 3 generally ineffective results) and were generally ineffective for clinical outcomes (18 reviews with 6 mixed and 9 generally ineffective results). Educational outreach visits (2 of 2 reviews), reminders (3 of 4 reviews), and provider incentives (1 of 1 review) were generally effective for cost reduction. Educational outreach visits (1 of 1 review) and provider incentives (1 of 1 review) were also generally effective for cost-effectiveness outcomes. Barriers to clinician adoption or adherence to guidelines included time constraints (8 reviews/overviews); limited staffing resources (2 overviews); timing (5 reviews/overviews); clinician skepticism (5 reviews/overviews); clinician knowledge of guidelines (4 reviews/overviews); and higher age of the clinician (1 overview). Facilitating factors included guideline characteristics such as format, resources, and end-user involvement (6 reviews/overviews); involving stakeholders (5 reviews/overviews); leadership support (5 reviews/overviews); scope of implementation (5 reviews/overviews); organizational culture such as multidisciplinary teams and low-baseline adherence (9 reviews/overviews); and electronic guidelines systems (3 reviews). CONCLUSION: The strategies of audit and feedback and educational outreach visits were generally effective in improving both process of care and clinical outcomes. Reminders and provider incentives showed mixed effectiveness, or were generally ineffective. No general conclusion could be reached about cost effectiveness, because of limitations in the evidence. Important gaps exist in the evidence on effectiveness of implementation interventions, especially regarding clinical outcomes, cost effectiveness and contextual issues affecting successful implementation.


Assuntos
Doenças Cardiovasculares/prevenção & controle , Doenças Hematológicas/prevenção & controle , Pneumopatias/prevenção & controle , American Heart Association , Doenças Cardiovasculares/diagnóstico , Doenças Hematológicas/diagnóstico , Humanos , Pneumopatias/diagnóstico , National Heart, Lung, and Blood Institute (U.S.) , Estados Unidos
13.
J Nat Prod ; 81(6): 1488-1492, 2018 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-29792325

RESUMO

Two new epimeric dihalogenated diaporthins, (9 R *)-8-methyl-9,11-dichlorodiaporthin (2) and (9 S *)-8-methyl-9,11-dichlorodiaporthin (3), have been isolated from the soil fungus Hamigera fusca NRRL 35721 alongside the known regioisomeric isocoumarin 8-methyl-11,11-dichlorodiaporthin (1). Their structures were elucidated by high-resolution mass spectrometry and NMR spectroscopy combined with molecular modeling. Compounds 1-3 are the first isocoumarins and the first halogenated metabolites ever reported from the Hamigera genus. The new compounds 2 and 3 display a non-geminal aliphatic dichlorination pattern unprecedented among known fungal dihalogenated aromatic polyketides. A bifunctional methyltransferase/aliphatic halogenase flavoenzyme is proposed to be involved in the biosynthesis of dichlorinated diaporthins 1-3. These metabolites are weakly cytotoxic.


Assuntos
Fungos/química , Pironas/química , Halogenação , Isocumarinas/química , Espectroscopia de Ressonância Magnética/métodos , Policetídeos/química
14.
JAMA ; 311(5): 507-20, 2014 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-24352797

RESUMO

Hypertension is the most common condition seen in primary care and leads to myocardial infarction, stroke, renal failure, and death if not detected early and treated appropriately. Patients want to be assured that blood pressure (BP) treatment will reduce their disease burden, while clinicians want guidance on hypertension management using the best scientific evidence. This report takes a rigorous, evidence-based approach to recommend treatment thresholds, goals, and medications in the management of hypertension in adults. Evidence was drawn from randomized controlled trials, which represent the gold standard for determining efficacy and effectiveness. Evidence quality and recommendations were graded based on their effect on important outcomes. There is strong evidence to support treating hypertensive persons aged 60 years or older to a BP goal of less than 150/90 mm Hg and hypertensive persons 30 through 59 years of age to a diastolic goal of less than 90 mm Hg; however, there is insufficient evidence in hypertensive persons younger than 60 years for a systolic goal, or in those younger than 30 years for a diastolic goal, so the panel recommends a BP of less than 140/90 mm Hg for those groups based on expert opinion. The same thresholds and goals are recommended for hypertensive adults with diabetes or nondiabetic chronic kidney disease (CKD) as for the general hypertensive population younger than 60 years. There is moderate evidence to support initiating drug treatment with an angiotensin-converting enzyme inhibitor, angiotensin receptor blocker, calcium channel blocker, or thiazide-type diuretic in the nonblack hypertensive population, including those with diabetes. In the black hypertensive population, including those with diabetes, a calcium channel blocker or thiazide-type diuretic is recommended as initial therapy. There is moderate evidence to support initial or add-on antihypertensive therapy with an angiotensin-converting enzyme inhibitor or angiotensin receptor blocker in persons with CKD to improve kidney outcomes. Although this guideline provides evidence-based recommendations for the management of high BP and should meet the clinical needs of most patients, these recommendations are not a substitute for clinical judgment, and decisions about care must carefully consider and incorporate the clinical characteristics and circumstances of each individual patient.


Assuntos
Anti-Hipertensivos/uso terapêutico , Hipertensão/tratamento farmacológico , Idoso , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Pressão Sanguínea , Bloqueadores dos Canais de Cálcio/uso terapêutico , Medicina Baseada em Evidências , Humanos , Hipertensão/complicações , Pessoa de Meia-Idade , Ensaios Clínicos Controlados Aleatórios como Assunto , Valores de Referência
15.
J Agric Food Chem ; 72(27): 15256-15264, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38935555

RESUMO

A study targeting novel antifungal metabolites identified potent in vitro antifungal activity against key plant pathogens in acetone extracts of Streptomyces sp. strain CA-296093. Feature-based molecular networking revealed the presence in this extract of antimycin-related compounds, leading to the isolation of four new compounds: escuzarmycins A-D (1-4). Extensive structural elucidation, employing 1D and 2D NMR, high-resolution mass spectrometry, Marfey's analysis, and NOESY correlations, confirmed their structures. The bioactivity of these compounds was tested against six fungal phytopathogens, and compounds 3 and 4 demonstrated strong efficacy, particularly against Zymoseptoria tritici, with compound 3 exhibiting the highest potency (EC50: 11 nM). Both compounds also displayed significant antifungal activity against Botrytis cinerea and Colletotrichum acutatum, with compound 4 proving to be the most potent. Despite moderate cytotoxicity against the human cancer cell line HepG2, compounds 3 and 4 emerge as promising fungicides for combating Septoria tritici blotch, anthracnose, and gray mold.


Assuntos
Ascomicetos , Colletotrichum , Fungicidas Industriais , Doenças das Plantas , Streptomyces , Fungicidas Industriais/farmacologia , Fungicidas Industriais/química , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Ascomicetos/efeitos dos fármacos , Ascomicetos/química , Streptomyces/química , Streptomyces/metabolismo , Humanos , Colletotrichum/efeitos dos fármacos , Botrytis/efeitos dos fármacos , Estrutura Molecular
16.
Microbiol Spectr ; 12(1): e0167923, 2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38009959

RESUMO

IMPORTANCE: The COVID-19 pandemic has revealed the lack of effective treatments against betacoronaviruses and the urgent need for new broad-spectrum antivirals. Natural products are a valuable source of bioactive compounds with pharmaceutical potential that may lead to the discovery of new antiviral agents. Specifically, compared to conventional synthetic molecules, microbial natural extracts possess a unique and vast chemical diversity and are amenable to large-scale production. The implementation of a high-throughput screening platform using the betacoronavirus OC43 in a human cell line infection model has provided proof of concept of the approach and has allowed for the rapid and efficient evaluation of 1,280 microbial extracts. The identification of several active compounds validates the potential of the platform for the search for new compounds with antiviral capacity.


Assuntos
Produtos Biológicos , Coronavirus Humano OC43 , Humanos , Produtos Biológicos/farmacologia , Produtos Biológicos/metabolismo , Pandemias , Linhagem Celular , Antivirais/farmacologia
17.
Int J Biol Macromol ; 264(Pt 1): 130458, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38423421

RESUMO

The PD-1/PD-L1 protein-protein interaction (PPI) controls an adaptive immune resistance mechanism exerted by tumor cells to evade immune responses. The large-molecule nature of current commercial monoclonal antibodies against this PPI hampers their effectiveness by limiting tumor penetration and inducing severe immune-related side effects. Synthetic small-molecule inhibitors may overcome such limitations and have demonstrated promising clinical translation, but their design is challenging. Microbial natural products (NPs) are a source of small molecules with vast chemical diversity that have proved anti-tumoral activities, but which immunotherapeutic properties as PD-1/PD-L1 inhibitors had remained uncharacterized so far. Here, we have developed the first cell-based PD-1/PD-L1 blockade reporter assay to screen NPs libraries. In this study, 6000 microbial extracts of maximum biosynthetic diversity were screened. A secondary metabolite called alpha-cyclopiazonic acid (α-CPA) of a bioactive fungal extract was confirmed as a new PD-1/PD-L1 inhibitor with low micromolar range in the cellular assay and in an additional cell-free competitive assay. Thermal denaturation experiments with PD-1 confirmed that the mechanism of inhibition is based on its stabilization upon binding to α-CPA. The identification of α-CPA as a novel PD-1 stabilizer proves the unprecedented resolution of this methodology at capturing specific PD-1/PD-L1 PPI inhibitors from chemically diverse NP libraries.


Assuntos
Antígeno B7-H1 , Neoplasias , Humanos , Antígeno B7-H1/metabolismo , Receptor de Morte Celular Programada 1/metabolismo , Anticorpos Monoclonais
18.
SLAS Technol ; 2023 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-37898289

RESUMO

Natural Products (NPs) are one of the main sources for drug discovery. Many clinical drugs are NPs or NP-inspired compounds, and recently discovered New Chemical Entities (NCEs) of NPs are emerging as promising new drugs. High-Throughput Screening (HTS) of large sample sets or libraries has grown to be vital for the drug discovery field. Industrial-scale HTS of NP libraries can be limited due to the difficulties entailed in working with tiny extract volumes and the variability in viscosity of NP extracts. For these reasons, the implementation of new technologies to miniaturize different reagent volumes grows to be fundamental. Since Acoustic Droplet Ejection (ADE) emerged as a helpful tool in HTS campaigns for the transference of compound libraries. The aim of this work was to test the effectiveness of ADE for the dispensation of NP extract libraries in cell-based HTS assays.

19.
J Fungi (Basel) ; 9(9)2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37754995

RESUMO

In a survey to evaluate the potential of lichens associated with gypsum areas as sources of new antifungal metabolites, six species of lichens were collected in the gypsum outcrops of the Sorbas Desert (Diploschistes ocellatus and Seirophora lacunosa) and the Tabernas Desert (Cladonia foliacea, Acarospora placodiformis, Squamarina lentigera and Xanthoparmelia pokornyi) in southern Spain. Raw lichen acetone extracts were tested against a panel of seven phytopathogenic fungi, including Botrytis cinerea, Colletotrichum acutatum, Fusarium oxysporum f.sp cubense TR4, Fusarium ploriferaum, Magnaporthe grisea, Verticillium dahliae and Zymoseptoria tritici. Active extracts of Cladonia foliacea, Xanthoparmelia pokornyi and Squamarina lentigera were analyzed by HPLC-MS/MS and Molecular Networking to identify possible metabolites responsible for the antifungal activity. A total of ten depside-like metabolites were identified by MS/MS dereplication and NMR experiments, of which one was a new derivative of fumaroprotocetraric acid. The compounds without previously described biological activity were purified and tested against the panel of fungal phytopathogens. Herein, the antifungal activity against fungal phytopathogens of 4'-O-methylpaludosic acid, divaricatic acid and stenosporic acid is reported for the first time. Stenosporic and divaricatic acids displayed a broad antifungal spectrum against seven relevant fungal phytopathogens in a micromolar range, including the extremely resistant fungus F. oxysporum f. sp. cubense Tropical Race 4 (TR4). 4'-O-methylpaludosic acid exhibited specific antifungal activity against the wheat pathogen Z. tritici, with an IC50 of 38.87 µg/mL (87.1 µM) in the absorbance-based assay and 24.88 µg/mL (55.52 µM) in the fluorescence-based assay.

20.
Pharmaceutics ; 15(2)2023 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-36839814

RESUMO

Memnoniella is a fungal genus from which a wide range of diverse biologically active compounds have been isolated. A Memnoniella dichroa CF-080171 extract was identified to exhibit potent activity against Plasmodium falciparum 3D7 and Trypanosoma cruzi Tulahuen whole parasites in a high-throughput screening (HTS) campaign of microbial extracts from the Fundación MEDINA's collection. Bioassay-guided isolation of the active metabolites from this extract afforded eight new meroterpenoids of varying potencies, namely, memnobotrins C-E (1-3), a glycosylated isobenzofuranone (4), a tricyclic isobenzofuranone (5), a tetracyclic benzopyrane (6), a tetracyclic isobenzofuranone (7), and a pentacyclic isobenzofuranone (8). The structures of the isolated compounds were established by (+)-ESI-TOF high-resolution mass spectrometry and nuclear magnetic resonance spectroscopy. Compounds 1, 2, and 4 exhibited potent antiparasitic activity against P. falciparum 3D7 (EC50 0.04-0.243 µM) and T. cruzi Tulahuen (EC50 0.266-1.37 µM) parasites, as well as cytotoxic activity against HepG2 tumoral liver cells (EC50 1.20-4.84 µM). The remaining compounds (3, 5-8) showed moderate or no activity against the above-mentioned parasites and cells.

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