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1.
J Am Chem Soc ; 146(27): 18626-18638, 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-38918178

RESUMEN

Metals are important cofactors in the metabolic processes of cyanobacteria, including photosynthesis, cellular respiration, DNA replication, and the biosynthesis of primary and secondary metabolites. In adaptation to the marine environment, cyanobacteria use metallophores to acquire trace metals when necessary as well as to reduce potential toxicity from excessive metal concentrations. Leptochelins A-C were identified as structurally novel metallophores from three geographically dispersed cyanobacteria of the genus Leptothoe. Determination of the complex structures of these metabolites presented numerous challenges, but they were ultimately solved using integrated data from NMR, mass spectrometry and deductions from the biosynthetic gene cluster. The leptochelins are comprised of halogenated linear NRPS-PKS hybrid products with multiple heterocycles that have potential for hexadentate and tetradentate coordination with metal ions. The genomes of the three leptochelin producers were sequenced, and retrobiosynthetic analysis revealed one candidate biosynthetic gene cluster (BGC) consistent with the structure of leptochelin. The putative BGC is highly homologous in all three Leptothoe strains, and all possess genetic signatures associated with metallophores. Postcolumn infusion of metals using an LC-MS metabolomics workflow performed with leptochelins A and B revealed promiscuous binding of iron, copper, cobalt, and zinc, with greatest preference for copper. Iron depletion and copper toxicity experiments support the hypothesis that leptochelin metallophores may play key ecological roles in iron acquisition and in copper detoxification. In addition, the leptochelins possess significant cytotoxicity against several cancer cell lines.


Asunto(s)
Cianobacterias , Cianobacterias/metabolismo , Cianobacterias/química , Cianobacterias/genética , Humanos , Familia de Multigenes , Línea Celular Tumoral , Antineoplásicos/química , Antineoplásicos/farmacología , Antineoplásicos/metabolismo
2.
Neuropathology ; 2024 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-38736183

RESUMEN

Medulloblastoma (MB) is the most prevalent malignant brain tumor in children, known for its heterogeneity and treatment-associated toxicity, and there is a critical need for new therapeutic targets. We analyzed the somatic mutation profile of 15 driver genes in 69 Latin-Iberian molecularly characterized medulloblastomas using the Illumina TruSight Tumor 15 panel. We classified the variants based on their clinical impact and oncogenicity. Among the patients, 66.7% were MBSHH, 13.0% MBWNT, 7.3% MBGrp3, and 13.0% MBGrp4. Among the 63 variants found, 54% were classified as Tier I/II and 31.7% as oncogenic/likely oncogenic. We observed 33.3% of cases harboring at least one mutation. TP53 (23.2%, 16/69) was the most mutated gene, followed by PIK3CA (5.8%, 4/69), KIT (4.3%, 3/69), PDGFRA (2.9%, 2/69), EGFR (1.4%, 1/69), ERBB2 (1.4%, 1/69), and NRAS (1.4%, 1/69). Approximately 41% of MBSHH tumors exhibited mutations, TP53 (32.6%) being the most frequently mutated gene. Tier I/II and oncogenic/likely oncogenic TP53 variants were associated with relapse, progression, and lower survival rates. Potentially actionable variants in the PIK3CA and KIT genes were identified. Latin-Iberian medulloblastomas, particularly the MBSHH, exhibit higher mutation frequencies than other populations. We corroborate the TP53 mutation status as an important prognostic factor, while PIK3CA and KIT are potential therapeutic targets.

3.
Mol Ecol ; 32(23): 6507-6522, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36541038

RESUMEN

Coccolithophores have global ecological and biogeochemical significance as the most important calcifying marine phytoplankton group. The structure and selection of prokaryotic communities associated with the most abundant coccolithophore and bloom-forming species, Emiliania huxleyi, are still poorly known. In this study, we assessed the diversity of bacterial communities associated with an E. huxleyi bloom in the Celtic Sea (Eastern North Atlantic), exposed axenic E. huxleyi cultures to prokaryotic communities derived from bloom and non-bloom conditions, and followed the dynamics of their microbiome composition over one year. Bloom-associated prokaryotic communities were dominated by SAR11, Marine group II Euryarchaeota and Rhodobacterales and contained substantial proportions of known indicators of phytoplankton bloom demises such as Flavobacteriaceae and Pseudoalteromonadaceae. The taxonomic richness of bacteria derived from natural communities associated with axenic E. huxleyi rapidly shifted and then stabilized over time. The succession of microorganisms recruited from the environment was consistently dependent on the composition of the initial bacterioplankton community. Phycosphere-associated communities derived from the E. huxleyi bloom were highly similar to one another, suggesting deterministic processes, whereas cultures from non-bloom conditions show an effect of stochasticity. Overall, this work sheds new light on the importance of the initial inoculum composition in microbiome recruitment and elucidates the temporal dynamics of its composition and long-term stability.


Asunto(s)
Haptophyta , Microbiota , Haptophyta/genética , Fitoplancton/genética , Organismos Acuáticos , Bacterias , Microbiota/genética
4.
Molecules ; 28(14)2023 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-37513486

RESUMEN

Alzheimer's disease (AD) is well-known among neurodegenerative diseases for the decline of cognitive functions, making overall daily tasks difficult or impossible. The disease prevails as the most common form of dementia and remains without a well-defined etiology. Being considered a disease of multifactorial origin, current targeted treatments have only managed to reduce or control symptoms, and to date, only two drugs are close to being able to halt its progression. For decades, natural compounds produced by living organisms have been at the forefront of research for new therapies. Mushrooms, which are well-known for their nutritional and medicinal properties, have also been studied for their potential use in the treatment of AD. Natural products derived from mushrooms have shown to be beneficial in several AD-related mechanisms, including the inhibition of acetylcholinesterase (AChE) and ß-secretase (BACE 1); the prevention of amyloid beta (Aß) aggregation and neurotoxicity; and the prevention of Tau expression and aggregation, as well as antioxidant and anti-inflammatory potential. Several studies in the literature relate mushrooms to neurodegenerative diseases. However, to the best of our knowledge, there is no publication that summarizes only AD data. In this context, this review aims to link the therapeutic potential of mushrooms to AD by compiling the anti-AD potential of different mushroom extracts or isolated compounds, targeting known AD-related mechanisms.


Asunto(s)
Agaricales , Enfermedad de Alzheimer , Enfermedades Neurodegenerativas , Humanos , Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/metabolismo , Péptidos beta-Amiloides/metabolismo , Agaricales/metabolismo , Acetilcolinesterasa/metabolismo
5.
Dev Biol ; 476: 79-87, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33753080

RESUMEN

Recent advances in rapid medical detection and diagnostic technology have extended both human health and life expectancy. However, ageing remains one of the critical risk factors in contributing to major incapacitating and fatal conditions, including cancer and neurodegeneration. Therefore, it is vital to study how ageing attributes to (or participates in) endangering human health via infliction of age-related diseases and what must be done to tackle this intractable process. This review encompasses the most recent literature elaborating the role of cell competition (CC) during ageing. CC is a process that occurs between two heterogeneous populations, where the cells with higher fitness levels have a competitive advantage over the neighbouring cells that have comparatively lower fitness levels. This interaction results in the selection of the fit cells, within a population, and elimination of the viable yet suboptimal cells. Therefore, it is tempting to speculate that, if this quality control mechanism works efficiently throughout life, can it ultimately lead to a healthier ageing and extended lifespan. Furthermore, the review aims to collate all the important state of the art publications that provides evidence of the relevance of CC in dietary restriction, stem cell dynamics, and cell senescence, thus, prompting us to advocate its contribution and in exploring new avenues and opportunities in fighting age-related conditions.


Asunto(s)
Envejecimiento/fisiología , Competencia Celular/fisiología , Senescencia Celular/fisiología , Envejecimiento/metabolismo , Animales , Comunicación Celular , Humanos , Neoplasias
6.
Pathobiology ; 89(3): 178-185, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35034013

RESUMEN

Herein, we present a rare case of a nine-month-old boy diagnosed with infant-type hemispheric glioma (gliosarcoma subtype) at the left frontal lobe. Following subtotal resection, the patient started chemotherapy with the BABY POG protocol. We describe the clinical diagnosis, histological characteristics, radiological features, molecular aspects, and management of this tumor. A comprehensive molecular analysis on the tumor tissue showed a TPR-NTRK1 gene fusion. The patient was treated with a TRK inhibitor, larotrectinib, and exhibited a stable disease with residual lesion following 8 months of target therapy. The present study is the first report of an infantile gliosarcoma harboring NTRK1 rearrangement treated with larotrectinib.


Asunto(s)
Astrocitoma , Glioma , Gliosarcoma , Glioma/tratamiento farmacológico , Glioma/genética , Gliosarcoma/tratamiento farmacológico , Humanos , Lactante , Masculino , Pirazoles/uso terapéutico , Pirimidinas , Receptor trkA/genética
7.
Mol Biol Rep ; 49(9): 9079-9087, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35708863

RESUMEN

BACKGROUND: There is an ongoing search for molecular markers that are specific, sensitive, and able to predict the stage of prostate cancer (PCa), which is the second most prevalent type of cancer in men worldwide. This study examined whether different single nucleotide polymorphisms (SNPs) were reliable markers of susceptibility to and prognosis of PCa in a sample of Brazilian patients. METHODS AND RESULTS: DNA samples were extracted from peripheral blood cells of 283 PCa patients and matched with samples from healthy controls. Single nucleotide polymorphisms (SNPs in four genes (BCL-2-rs2279115, CASP3-rs4647603, CASP9-rs1052571, and NKX3-1-rs11781886) were genotyped by real-time PCR using the TaqMan® probe. Odds Ratios with 95% confidence intervals were calculated for allelic and genotypic frequencies. The association between polymorphic variants, risk of developing PCa, and clinicopathological characteristics was analyzed by univariate and multivariate logistic regression analysis. SNPs in CASP3, CASP9, and NKX3-1 genes, either alone or in combination (BCL-2+NKX3-1 and CASP3+NKX3-1) were associated with the risk of developing PCa. Genotypes and tumor histopathological data indicated that the BCL-2, NKX3-1, and CASP3 allelic variants, either alone or combined in pairs, were associated with a poor prognosis of PCa. CONCLUSIONS: Genetic polymorphisms in CASP3, NKX3-1, and BCL-2 genes were associated with susceptibility to PCa. The SNPs in the three genes alone and the SNP in the BCL-2 gene combined with the other two genes were strongly associated with adverse outcomes in PCa patients and are promising candidates for molecular markers for PCa prognosis.


Asunto(s)
Genes bcl-2 , Neoplasias de la Próstata , Estudios de Casos y Controles , Caspasa 3/genética , Caspasa 9/genética , Predisposición Genética a la Enfermedad , Proteínas de Homeodominio/genética , Humanos , Masculino , Polimorfismo de Nucleótido Simple/genética , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/patología , Proteínas Proto-Oncogénicas c-bcl-2/genética , Factores de Transcripción/genética
8.
J Nat Prod ; 85(2): 391-404, 2022 02 25.
Artículo en Inglés | MEDLINE | ID: mdl-35107279

RESUMEN

To enable the further exploration of structure-activity relationships (SARs) of proanthocyanidins (PACs) with dentin biomodification abilities, Cinnamomum verum was selected for scaled-up purification of mixed A-/B-type, medium-size PAC oligomers. Sequential purification by centrifugal partition chromatography (CPC), Sephadex LH-20, and semiprep HPLC chromatography yielded four underivatized tetrameric (5-8) and two pentameric (9-10) PACs. Their unambiguous structural characterization involved extensive spectral and chemical degradation approaches to show that epicatechin units are connected by plant-specific combinations of doubly linked A- and singly linked B-type interflavanyl bonds. The biomechanical properties (via dynamic mechanical analysis) and physicochemical structure (via infrared spectroscopy) were assessed to evaluate the biomodification potency of PAC-treated collagen in a preclinical dentin model. This study revealed that (4→8) versus (4→6) bonds in PAC interflavan linkages have limited influence on biomechanical outcomes of dentin. By exhibiting a 25-fold increase in the complex modulus of treated dentin compared to control, aesculitannin E (5) was found to be the most potent PAC known to date for enhancing the mechanical properties of dentin in this preclinical model.


Asunto(s)
Catequina , Proantocianidinas , Catequina/análisis , Cinnamomum zeylanicum/química , Dentina/química , Corteza de la Planta/química , Proantocianidinas/química
9.
J Nat Prod ; 85(12): 2753-2768, 2022 12 23.
Artículo en Inglés | MEDLINE | ID: mdl-36382951

RESUMEN

Investigation of a pine bark extract for bioactive proanthocyanidin oligomers resulted in the isolation of structurally related dimeric seco B-type procyanidin derivatives, 1-5. This includes scalemic mixtures of gambiriin A1 (1a) and A2 (2a) and their newly described optical antipodes, ent-gambiriin A1 (1b) and ent-gambiriin A2 (2b), respectively, as well as a racemic mixture of the newly described (ent-)gambiriin A5 (3a/3b). Furthermore, the study now fully characterizes the previously reported optically pure dimers gambiriin B1 (4) and gambirflavan D1 (5), and characterized the novel seco B-type procyanidin trimer, 6 (gambirifuran C1). Thermal conversion of catechin in aqueous solution provided further evidence for the structures of 1-6 and led to the purification of semisynthetic 1a and 2a as well as additional dimers 7-10. Elucidating the structures of the natural dimers, 1-5, from comprehensive NMR and ECD data and synthetic evidence provided crucial reference points for establishing the structure of the seco B-type procyanidin trimer, 6. Serving as assigned building blocks, data from the dimers supported the 3D structural assignment of 6 based on NMR substituent chemical shift differences (s.c.s., syn. ΔδC) and component-based empirical ECD calculations. Within the newly characterized series of PAC-related molecules, 5 exhibited high dentin biomodification potential. In addition, considering the nomenclature issues and plausible biosynthetic pathways of this group of compounds led to a consolidated nomenclature of all currently known seco B-type procyanidins. These findings, thereby, expand the chemical space of bioactive catechin oligomers, which have promise as agents for the natural enhancement of dental biomaterials. Finally, the current knowledge of the chemical space of seco B-type procyanidin derivatives was compiled to the level of absolute configuration.


Asunto(s)
Biflavonoides , Catequina , Pinus , Proantocianidinas , Proantocianidinas/química , Catequina/química , Biflavonoides/química
10.
Phytother Res ; 36(6): 2416-2433, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35583746

RESUMEN

Endometriosis, a gynecological disease that affects reproductive age women is difficultly controlled in the long term by currently available treatments, prompting patients to adopt self-controlled interventions including dietary changes. The aim of this review is to provide evidence of how curcumin, quercetin, and resveratrol can act as natural interventions to control endometriosis. The review followed PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. A comprehensive search was carried out in PubMed, Scopus, and Web of Science to gather together all the articles that study the specific actions of curcumin, resveratrol, or quercetin in endometriosis pathophysiology. All types of study designs including experimental data were considered. Thirty articles, including a clinical trial, were included. For the assessment of the quality of the selected studies that globally have "good quality", the GRADE (Grading of Recommendations Assessment, Development and Evaluation) and the SYRCLE ROB tool criteria were used. By acting on mechanisms of inflammation, oxidative stress, cell proliferation, invasion and adhesion, apoptosis, angiogenesis and glucose and lipid metabolism, curcumin, quercetin, and resveratrol showed to have beneficial effects, evidencing their potential application in the endometriosis treatment. However, future clinical studies are necessary to determine the real efficacy of these compounds in human endometriosis.


Asunto(s)
Curcumina , Endometriosis , Antioxidantes/farmacología , Antioxidantes/uso terapéutico , Curcumina/farmacología , Curcumina/uso terapéutico , Endometriosis/tratamiento farmacológico , Femenino , Humanos , Quercetina/farmacología , Quercetina/uso terapéutico , Resveratrol/farmacología , Resveratrol/uso terapéutico
11.
J Neurooncol ; 151(2): 135-144, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33400009

RESUMEN

INTRODUCTION: Glioblastoma (GBM) is the deadliest primary brain tumor. The standard treatment consists of surgery, radiotherapy, and temozolomide (TMZ). TMZ response is heterogeneous, and MGMT promoter (MGMTp) methylation has been the major predictive biomarker. We aimed to describe the clinical and molecular data of GBMs treated with TMZ, compare MGMT methylation with MGMT expression, and further associate with patient's outcome. METHODS: We evaluate 112 FFPE adult GBM cases. IDH1 and ATRX expression was analyzed by immunohistochemistry, hotspot TERT promoter (TERTp) mutations were evaluated by Sanger or pyrosequencing, and MGMTp methylation was assessed by pyrosequencing and MGMT mRNA expression using the nCounter® Vantage 3D™ DNA damage and repair panel. RESULTS: Of the 112 GBMs, 96 were IDH1WT, and 16 were IDH1MUT. Positive ATRX expression was found in 91.6% (88/96) of IDHWT and 43.7% (7/16) of IDHMUT. TERTp mutations were detected in 70.4% (50/71) of IDHWT. MGMTp methylation was found in 55.5% (35/63) of IDHWT and 84.6% (11/13) of IDHMUT, and as expected, MGMTp methylation was significantly associated with a better response to TMZ. MGMT expression was inversely correlated with MGMTp methylation levels (- 0.506, p < 0.0001), and MGMT low expression were significantly associated with better patient survival. It was also observed that integrating MGMTp methylation and expression, significantly improved the prognostication value. CONCLUSIONS: MGMT mRNA levels evaluated by digital expression were associated with the outcome of TMZ-treated GBM patients. The combination of MGMT methylation and mRNA expression may provide a more accurate prediction of TMZ response in GBM patients.


Asunto(s)
Neoplasias Encefálicas/mortalidad , Metilasas de Modificación del ADN/metabolismo , Enzimas Reparadoras del ADN/metabolismo , Glioblastoma/mortalidad , Isocitrato Deshidrogenasa/genética , Mutación , Temozolomida/uso terapéutico , Proteínas Supresoras de Tumor/metabolismo , Adulto , Anciano , Antineoplásicos Alquilantes/uso terapéutico , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Femenino , Estudios de Seguimiento , Glioblastoma/tratamiento farmacológico , Glioblastoma/genética , Glioblastoma/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos , Tasa de Supervivencia
12.
Biofouling ; 37(2): 246-256, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33730946

RESUMEN

Microfouling, ie biofilm formation on surfaces, can have an economic impact and requires costly maintenance in water-powered energy generation systems. In this study, the microbiota of a cooling system (filter and heat exchanger) in the Irapé hydroelectric power plant in Brazil was examined. The goal was to identify bacteria that could be targeted to more efficiently reduce biofilm formation. Two sampling campaigns were made corresponding to two well-defined seasons of the Brazilian Cerrado biome: the dry (campaign 1) and the wet (campaign 2). Microfouling communities varied considerably over time in samples obtained at different times after the last clearance of the heat exchanger. The thermophilic bacteria Meiothermus, Thermomonas and Symbiobacterium were exclusive and abundant in the microfouling of the heat exchanger in campaign 2, while methanotrophs and iron-reducing bacteria were abundant only in filter sediments. These findings could help to guide strategies for ecofriendly measures to reduce biofilm fouling in hydroelectric power plants, minimizing environmental and economic losses.


Asunto(s)
Bacterias , Agua , Archaea , Bacterias/genética , Biopelículas , Brasil
13.
Mar Drugs ; 19(11)2021 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-34822504

RESUMEN

The Blue Biotechnology and Ecotoxicology Culture Collection (LEGE-CC) holds a vast number of cyanobacteria whose chemical richness is still largely unknown. To expedite its bioactivity screening we developed a natural products library. Sixty strains and four environmental samples were chromatographed, using a semiautomatic HPLC system, yielding 512 fractions that were tested for their cytotoxic activity against 2D and 3D models of human colon carcinoma (HCT 116), and non-cancerous cell line hCMEC/D3. Six fractions showed high cytotoxicity against 2D and 3D cell models (group A), and six other fractions were selected by their effects on 3D cells (group B). The metabolome of each group was organized and characterized using the MolNetEnhancer workflow, and its processing with MetaboAnalyst allowed discrimination of the mass features with the highest fold change, and thus the ones that might be bioactive. Of those, mass features without precedented identification were mostly found in group A, indicating seven possible novel bioactive molecules, alongside in silico putative annotation of five cytotoxic compounds. Manual dereplication of group B tentatively identified nine pheophytin and pheophorbide derivatives. Our approach enabled the selection of 7 out of 60 cyanobacterial strains for anticancer drug discovery, providing new data concerning the chemical composition of these cyanobacteria.


Asunto(s)
Antineoplásicos/farmacología , Cianobacterias , Animales , Antineoplásicos/química , Organismos Acuáticos , Productos Biológicos , Línea Celular Tumoral/efectos de los fármacos , Descubrimiento de Drogas , Humanos , Metabolómica
14.
Mar Drugs ; 19(8)2021 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-34436254

RESUMEN

Grateloupia turuturu Yamada, 1941, is a red seaweed widely used for food in Japan and Korea which was recorded on the Atlantic Coast of Europe about twenty years ago. This seaweed presents eicosapentaenoic acid (EPA) and other polyunsaturated fatty acids (PUFAs) in its lipid fraction, a feature that sparked the interest on its potential applications. In seaweeds, PUFAs are mostly esterified to polar lipids, emerging as healthy phytochemicals. However, to date, these biomolecules are still unknown for G. turuturu. The present work aimed to identify the polar lipid profile of G. turuturu, using modern lipidomics approaches based on high performance liquid chromatography coupled to high resolution mass spectrometry (LC-MS) and gas chromatography coupled to mass spectrometry (GC-MS). The health benefits of polar lipids were identified by health lipid indices and the assessment of antioxidant and anti-inflammatory activities. The polar lipids profile identified from G. turuturu included 205 lipid species distributed over glycolipids, phospholipids, betaine lipids and phosphosphingolipids, which featured a high number of lipid species with EPA and PUFAs. The nutritional value of G. turuturu has been shown by its protein content, fatty acyl composition and health lipid indices, thus confirming G. turuturu as an alternative source of protein and lipids. Some of the lipid species assigned were associated to biological activity, as polar lipid extracts showed antioxidant activity evidenced by free radical scavenging potential for the 2,2'-azino-bis-3-ethyl benzothiazoline-6-sulfonic acid (ABTS●+) radical (IC50 ca. 130.4 µg mL-1) and for the 2,2-diphenyl-1-picrylhydrazyl (DPPH●) radical (IC25 ca. 129.1 µg mL-1) and anti-inflammatory activity by inhibition of the COX-2 enzyme (IC50 ca. 33 µg mL-1). Both antioxidant and anti-inflammatory activities were detected using a low concentration of extracts. This integrative approach contributes to increase the knowledge of G. turuturu as a species capable of providing nutrients and bioactive molecules with potential applications in the nutraceutical, pharmaceutical and cosmeceutical industries.


Asunto(s)
Antioxidantes/farmacología , Extractos Vegetales/farmacología , Algas Marinas , Compuestos de Bifenilo , Cromatografía Líquida de Alta Presión , Cromatografía Liquida , Ácidos Grasos Insaturados/farmacología , Humanos , Lipidómica , Espectrometría de Masas , Fosfolípidos/farmacología , Picratos , Relación Estructura-Actividad
15.
Mar Drugs ; 19(12)2021 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-34940674

RESUMEN

Lipids are one of the primary metabolites of microalgae and cyanobacteria, which enrich their utility in the pharmaceutical, feed, cosmetic, and chemistry sectors. This work describes the isolation, structural elucidation, and the antibiotic and antibiofilm activities of diverse lipids produced by different microalgae and cyanobacteria strains from two European collections (ACOI and LEGE-CC). Three microalgae strains and one cyanobacteria strain were selected for their antibacterial and/or antibiofilm activity after the screening of about 600 strains carried out under the NoMorFilm European project. The total organic extracts were firstly fractionated using solid phase extraction methods, and the minimum inhibitory concentration and minimal biofilm inhibitory concentration against an array of human pathogens were determined. The isolation was carried out by bioassay-guided HPLC-DAD purification, and the structure of the isolated molecules responsible for the observed activities was determined by HPLC-HRESIMS and NMR methods. Sulfoquinovosyldiacylglycerol, monogalactosylmonoacylglycerol, sulfoquinovosylmonoacylglycerol, α-linolenic acid, hexadeca-4,7,10,13-tetraenoic acid (HDTA), palmitoleic acid, and lysophosphatidylcholine were found among the different active sub-fractions selected. In conclusion, cyanobacteria and microalgae produce a great variety of lipids with antibiotic and antibiofilm activity against the most important pathogens causing severe infections in humans. The use of these lipids in clinical treatments alone or in combination with antibiotics may provide an alternative to the current treatments.


Asunto(s)
Antibacterianos/farmacología , Biopelículas/efectos de los fármacos , Cianobacterias , Lípidos/farmacología , Microalgas , Animales , Antibacterianos/química , Organismos Acuáticos , Lípidos/química , Pruebas de Sensibilidad Microbiana , Staphylococcus aureus/efectos de los fármacos
16.
J Org Chem ; 85(13): 8462-8479, 2020 07 02.
Artículo en Inglés | MEDLINE | ID: mdl-32551610

RESUMEN

Guided by dentin biomechanical bioactivity, this phytochemical study led to the elucidation of an extended set of structurally demanding proanthocyanidins (PACs). Unambiguous structure determination involved detailed spectroscopic and chemical characterization of four A-type dimers (2 and 4-6), seven trimers (10-16), and six tetramers (17-22). New outcomes confirm the feasibility of determining the absolute configuration of the catechol monomers in oligomeric PACs by one-dimensional (1D) and two-dimensional (2D) NMR. Electronic circular dichroism as well as phloroglucinolysis followed by mass spectrometry and chiral phase high-performance liquid chromatography (HPLC) analysis generated the necessary chiral reference data. In the context of previously reported dentin-bioactive PACs, accurately and precisely assigned 13C NMR resonances enabled absolute stereochemical assignments of PAC monomers via (i) inclusion of the 13C NMR γ-gauche effect and (ii) determination of differential 13C chemical shift values (ΔδC) in comparison with those of the terminal monomer (unit II) in the dimers 2 and 4-6. Among the 13 fully elucidated PACs, eight were identified as new, and one structure (11) was revised based on new knowledge gained regarding the subtle, stereospecific spectroscopic properties of PACs.


Asunto(s)
Pinus , Proantocianidinas , Cromatografía Líquida de Alta Presión , Dentina , Espectrometría de Masas
17.
J Nat Prod ; 83(6): 1885-1890, 2020 06 26.
Artículo en Inglés | MEDLINE | ID: mdl-32479093

RESUMEN

Four natural lactylates of chlorinated fatty acids, chlorosphaerolactylates A-D (1-4), were isolated from the methanolic extract of the cyanobacterium Sphaerospermopsis sp. LEGE 00249 through a combination of bioassay-guided and MS-guided approaches. Compounds 1-4 are esters of (mono-, di-, or tri)chlorinated lauric acid and lactic acid, whose structures were assigned on the basis of spectrometric and spectroscopic methods inclusive of 1D and 2D NMR experiments. High-resolution mass-spectrometry data sets also demonstrated the existence of other minor components that were identified as chlorosphaero(bis)lactylate analogues. The chlorosphaerolactylates were tested for potential antibacterial, antifungal, and antibiofilm properties using bacterial and fungal clinical isolates. Compounds 1-4 showed a weak inhibitory effect on the growth of Staphylococcus aureus S54F9 and Candida parapsilosis SMI416, as well as on the biofilm formation of coagulase-negative Staphylococcus hominis FI31.


Asunto(s)
Antiinfecciosos/química , Cianobacterias/química , Ácidos Grasos/química , Antibacterianos/farmacología , Antiinfecciosos/aislamiento & purificación , Antiinfecciosos/farmacología , Antifúngicos/farmacología , Biopelículas/efectos de los fármacos , Candida/efectos de los fármacos , Ácidos Grasos/aislamiento & purificación , Ácidos Grasos/farmacología , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Staphylococcus aureus/efectos de los fármacos , Staphylococcus hominis/efectos de los fármacos
18.
Mar Drugs ; 18(2)2020 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-32013082

RESUMEN

Marine organisms, including seagrasses, are important sources of biologically active molecules for the treatment of human diseases. In this study, organic extracts of the marine seagrass Halophila stipulacea obtained by different polarities from leaves (L) and stems (S) (hexane [HL, HS], ethyl acetate [EL, ES], and methanol [ML, MS]) were tested for different bioactivities. The screening comprehended the cytotoxicity activity against cancer cell lines grown as a monolayer culture or as multicellular spheroids (cancer), glucose uptake in cells (diabetes), reduction of lipid content in fatty acid-overloaded liver cells (steatosis), and lipid-reducing activity in zebrafish larvae (obesity), as well as the antifouling activity against marine bacteria (microfouling) and mussel larval settlement (macrofouling). HL, EL, HS, and ES extracts showed statistically significant cytotoxicity against cancer cell lines. The extracts did not have any significant effect on glucose uptake and on the reduction of lipids in liver cells. The EL and ML extracts reduced neutral lipid contents on the larvae of zebrafish with EC50 values of 2.2 µg/mL for EL and 1.2 µg/mL for ML. For the antifouling activity, the HS and ML extracts showed a significant inhibitory effect (p < 0.05) against the settlement of Mytilus galloprovincialis plantigrade larvae. The metabolite profiling using HR-LC-MS/MS and GNPS (The Global Natural Product Social Molecular Networking) analyses identified a variety of known primary and secondary metabolites in the extracts, along with some unreported molecules. Various compounds were detected with known activities on cancer (polyphenols: Luteolin, apeginin, matairesinol), on metabolic diseases (polyphenols: cirsimarin, spiraeoside, 2,4-dihydroxyheptadec-16-ynyl acetate; amino acids: N-acetyl-L-tyrosine), or on antifouling (fatty acids: 13-decosenamide; cinnamic acids: 3-hydroxy-4-methoxycinnamic acid, alpha-cyano-4-hydroxycinnamic), which could be, in part, responsible for the observed bioactivities. In summary, this study revealed that Halophila stipulacea is a rich source of metabolites with promising activities against obesity and biofouling and suggests that this seagrass could be useful for drug discovery in the future.


Asunto(s)
Antibacterianos/farmacología , Hydrocharitaceae , Obesidad , Extractos Vegetales/farmacología , Incrustaciones Biológicas/prevención & control , Productos Biológicos
19.
Microb Ecol ; 78(3): 575-588, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30706113

RESUMEN

Water hyacinth (WH), a large floating plant, plays an important role in the biogeochemistry and ecology of many freshwaters globally. Its biogeochemical impact on wetland functioning is strongly mediated by the microbiome associated with its roots. However, little is known about the structure and function of this WH rhizobiome and its relation to wetland ecosystem functioning. Here, we unveil the core and transient rhizobiomes of WH and their key biogeochemical functions in two of the world's largest wetlands: the Amazon and the Pantanal. WH hosts a highly diverse microbial community shaped by spatiotemporal changes. Proteobacteria lineages were most common, followed by Actinobacteria and Planctomycetes. Deltaproteobacteria and Sphingobacteriia predominated in the core microbiome, potentially associated with polysaccharide degradation and fermentation of plant-derived carbon. Conversely, a plethora of lineages were transient, including highly abundant Acinetobacter, Acidobacteria subgroup 6, and methanotrophs, thus assuring diverse taxonomic signatures in the two different wetlands. Our findings point out that methanogenesis is a key driver of, and proxy for, community structure, especially during seasonal plant decline. We provide ecologically relevant insights into the WH microbiome, which is a key element linking plant-associated carbon turnover with other biogeochemical fluxes in tropical wetlands.


Asunto(s)
Bacterias/aislamiento & purificación , Bacterias/metabolismo , Carbono/metabolismo , Eichhornia/microbiología , Microbiota , Bacterias/clasificación , Bacterias/genética , ADN Bacteriano/genética , Ecosistema , Nutrientes/metabolismo , Filogenia , ARN Ribosómico 16S/genética
20.
Ear Hear ; 40(6): 1445-1456, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30998544

RESUMEN

OBJECTIVES: The aims of this study were as follows: (a) to describe audiologists' practices toward auditory training (AT) for adult cochlear implant (CI) users with a postlingual hearing loss; and (b) to assess the cost of different AT methods for clients and service providers in comparison with no AT delivery. DESIGN: A survey was distributed to approximately 230 Australian CI audiologists to investigate the range, magnitude, and rationale of AT practices adopted as part of rehabilitation services with adult CI users. The cost of these different AT practices was then estimated from the perspectives of both clients and service providers, and compared against no AT delivery. RESULTS: Seventy-eight audiologists responded to at least one section of the survey (16% to 33% response rate), of which 85.5% reported that they viewed AT as a necessary component of rehabilitation. Home-based and face-to-face were the methods most frequently adopted to deliver AT. Methods used during training, such as stimuli type, feedback, and encouragement for training adherence, varied across respondents. The cost analysis indicated that home-based training resulted in the lowest program costs, whereas face-to-face AT (when delivered independently from routine appointments) was the method with highest cost for clients and service providers. CONCLUSIONS: The type of AT, recommended frequency of sessions, and overall duration of programs varied widely across respondents. Costs incurred by clients depended mainly on whether the AT was home-based or clinician-led (i.e., face-to-face, group-based), program fees, and travel arrangements made by clients, as well as clinicians' wages and the method chosen to deliver AT.


Asunto(s)
Audiólogos/estadística & datos numéricos , Implantes Cocleares , Corrección de Deficiencia Auditiva/estadística & datos numéricos , Adulto , Anciano , Actitud del Personal de Salud , Australia , Implantación Coclear , Corrección de Deficiencia Auditiva/economía , Costos y Análisis de Costo , Atención a la Salud/economía , Atención a la Salud/estadística & datos numéricos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Encuestas y Cuestionarios , Adulto Joven
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