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1.
Front Microbiol ; 15: 1432475, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39282555

RESUMO

A considerable number of antibacterial agents are derived from bacterial metabolites. Similarly, numerous known compounds that impede bacterial virulence stem from bacterial metabolites. Enteropathogenic Escherichia coli (EPEC) is a notable human pathogen causing intestinal infections, particularly affecting infant mortality in developing regions. These infections are characterized by microvilli effacement and intestinal epithelial lesions linked with aberrant actin polymerization. This study aimed to identify potential antivirulence compounds for EPEC infections among bacterial metabolites harvested from marine actinobacteria (Kocuria sp. and Rhodococcus spp.) from the Arctic Sea by the application of virulence-based screening assays. Moreover, we demonstrate the suitability of these antivirulence assays to screen actinobacteria extract fractions for the bioassay-guided identification of metabolites. We discovered a compound in the fifth fraction of a Kocuria strain that interferes with EPEC-induced actin polymerization without affecting growth. Furthermore, a growth-inhibiting compound was identified in the fifth fraction of a Rhodococcus strain. Our findings include the bioassay-guided identification, HPLC-MS-based dereplication, and isolation of a large phospholipid and a likely antimicrobial peptide, demonstrating the usefulness of this approach in screening for compounds capable of inhibiting EPEC virulence.

2.
Rheumatology (Oxford) ; 63(7): 1772-1778, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38949781

RESUMO

SLE presents significant challenges for patients and health-care professionals (HCPs), both across Europe and worldwide. Improving health-care outcomes for patients with SLE requires a comprehensive understanding of patient disease pathways. In particular, the geographical distance between SLE patients and specialized care centres, combined with the scarcity of rheumatologists, exacerbates delays in diagnosis and management. Also, the initial SLE symptoms can often be non-specific, and providing guidelines for primary HCPs and other non-specialists is extremely important. Improvement in access to treatment is also important, with several recently approved therapies for SLE not being available in several European countries and many low- and middle-income countries (LMICs). Furthermore, in the LMICs in which these treatments are available, they are not always covered by the health-care system, making their access almost impossible for those of lower socio-economic status. A number of provisions are already in place within the European Union, to improve access to care for patients with rare and complex diseases, including those with SLE. In particular, European Reference Networks (ERNs), such the ERN for Autoimmune Diseases ReCONNET, are virtual networks involving HCPs across Europe with the aim of improving the care of patients with rare and complex diseases that require highly specialized treatment and a concentration of knowledge and resources. In addition, lupus patient organizations such as Lupus Europe play a crucial role in raising awareness of SLE and advocating for improved access to care. Together, we can work towards a future where all people living with lupus receive the comprehensive and timely care they deserve.


Assuntos
Acessibilidade aos Serviços de Saúde , Lúpus Eritematoso Sistêmico , Humanos , Lúpus Eritematoso Sistêmico/terapia , Europa (Continente) , Saúde Global
3.
Lancet Rheumatol ; 6(8): e573-e586, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38876127

RESUMO

Maternal autoimmune rheumatic diseases can influence the outcomes of children through several life stages. During pregnancy, maternal inflammation and autoantibodies can hinder fetal development and lead to growth restriction, preterm birth, and low birth weight; prematurity, especially at extreme gestational ages, can in turn impair future child health. Treatment with compatible immunomodulatory drugs and preventive medications aims to keep maternal disease under control and minimise the risk of adverse pregnancy outcomes. However, concerns have been raised about the effects of immunomodulatory drugs on neonatal conditions (ie, the risk of serious infections, inadequate responses to vaccinations, and organ toxicity) and long-term outcomes (metabolic and cardiovascular problems and neurodevelopmental disorders). Among the unmet needs of parents with autoimmune rheumatic diseases, there is the estimation of risk for the children to develop autoimmune disorders and the need for reassurance about parenting capacity while living with a chronic condition. This Series paper provides a comprehensive overview of the literature and guidance on discussing these topics with patients.


Assuntos
Doenças Autoimunes , Complicações na Gravidez , Doenças Reumáticas , Humanos , Doenças Reumáticas/imunologia , Doenças Reumáticas/tratamento farmacológico , Gravidez , Feminino , Doenças Autoimunes/imunologia , Recém-Nascido , Complicações na Gravidez/imunologia , Complicações na Gravidez/tratamento farmacológico , Resultado da Gravidez/epidemiologia , Efeitos Tardios da Exposição Pré-Natal/imunologia , Criança , Nascimento Prematuro
4.
Sci Rep ; 14(1): 10237, 2024 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-38702505

RESUMO

Enzymatic degradation of algae cell wall carbohydrates by microorganisms is under increasing investigation as marine organic matter gains more value as a sustainable resource. The fate of carbon in the marine ecosystem is in part driven by these degradation processes. In this study, we observe the microbiome dynamics of the macroalga Fucus vesiculosus in 25-day-enrichment cultures resulting in partial degradation of the brown algae. Microbial community analyses revealed the phylum Pseudomonadota as the main bacterial fraction dominated by the genera Marinomonas and Vibrio. More importantly, a metagenome-based Hidden Markov model for specific glycosyl hydrolyses and sulphatases identified Bacteroidota as the phylum with the highest potential for cell wall degradation, contrary to their low abundance. For experimental verification, we cloned, expressed, and biochemically characterised two α-L-fucosidases, FUJM18 and FUJM20. While protein structure predictions suggest the highest similarity to a Bacillota origin, protein-protein blasts solely showed weak similarities to defined Bacteroidota proteins. Both enzymes were remarkably active at elevated temperatures and are the basis for a potential synthetic enzyme cocktail for large-scale algal destruction.


Assuntos
Parede Celular , Fucus , Metagenômica , Parede Celular/metabolismo , Fucus/metabolismo , Fucus/genética , Fucus/microbiologia , Metagenômica/métodos , Bacteroidetes/genética , Bacteroidetes/enzimologia , Metagenoma , Microbiota , Filogenia
5.
Ann Rheum Dis ; 83(1): 15-29, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-37827694

RESUMO

OBJECTIVES: To update the EULAR recommendations for the management of systemic lupus erythematosus (SLE) based on emerging new evidence. METHODS: An international Task Force formed the questions for the systematic literature reviews (January 2018-December 2022), followed by formulation and finalisation of the statements after a series of meetings. A predefined voting process was applied to each overarching principle and recommendation. Levels of evidence and strengths of recommendation were assigned, and participants finally provided their level of agreement with each item. RESULTS: The Task Force agreed on 5 overarching principles and 13 recommendations, concerning the use of hydroxychloroquine (HCQ), glucocorticoids (GC), immunosuppressive drugs (ISDs) (including methotrexate, mycophenolate, azathioprine, cyclophosphamide (CYC)), calcineurin inhibitors (CNIs, cyclosporine, tacrolimus, voclosporin) and biologics (belimumab, anifrolumab, rituximab). Advice is also provided on treatment strategies and targets of therapy, assessment of response, combination and sequential therapies, and tapering of therapy. HCQ is recommended for all patients with lupus at a target dose 5 mg/kg real body weight/day, considering the individual's risk for flares and retinal toxicity. GC are used as 'bridging therapy' during periods of disease activity; for maintenance treatment, they should be minimised to equal or less than 5 mg/day (prednisone equivalent) and, when possible, withdrawn. Prompt initiation of ISDs (methotrexate, azathioprine, mycophenolate) and/or biological agents (anifrolumab, belimumab) should be considered to control the disease and facilitate GC tapering/discontinuation. CYC and rituximab should be considered in organ-threatening and refractory disease, respectively. For active lupus nephritis, GC, mycophenolate or low-dose intravenous CYC are recommended as anchor drugs, and add-on therapy with belimumab or CNIs (voclosporin or tacrolimus) should be considered. Updated specific recommendations are also provided for cutaneous, neuropsychiatric and haematological disease, SLE-associated antiphospholipid syndrome, kidney protection, as well as preventative measures for infections, osteoporosis, cardiovascular disease. CONCLUSION: The updated recommendations provide consensus guidance on the management of SLE, combining evidence and expert opinion.


Assuntos
Azatioprina , Lúpus Eritematoso Sistêmico , Humanos , Azatioprina/uso terapêutico , Tacrolimo/uso terapêutico , Rituximab/uso terapêutico , Metotrexato/uso terapêutico , Lúpus Eritematoso Sistêmico/complicações , Imunossupressores/uso terapêutico , Ciclofosfamida/uso terapêutico , Hidroxicloroquina/uso terapêutico , Glucocorticoides/uso terapêutico , Inibidores Enzimáticos/uso terapêutico
6.
Adv Simul (Lond) ; 8(1): 30, 2023 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-38098131

RESUMO

BACKGROUND: Simulation in healthcare attempts to create relevant representations of patient encounters. It provides experiential learning, bridging typical classroom activities and clinical practice. This study aims to investigate whether the principle of Peer-Assisted Learning can be used in simulation by letting simulation-experienced paramedic students prepare, deliver, and debrief their own simulations, with minimal faculty assistance. This could be a way to support student learning by being involved in teaching, and it might at the same time optimise the cost-effectiveness of simulation-based training. METHODS: This observational non-inferiority study compared reflection levels between facilitator-led and student-led simulation and debriefing, between scenario types, and compared the number of turns in which students are involved in both settings. Third-year Bachelor in Paramedic Science students' debriefings were filmed and transcribed. The degree of reflection in students' statements was rated according to a modified version of Fleck's analytical framework of reflection levels, assigning scores from lowest (R0 description) to highest (R4 critical reflection). Facilitator-led and student-led debriefings were compared using chi-square tests. Scenarios were also analysed according to type (paediatric emergencies and complex assessments) regardless of who led the simulation. RESULTS: Ten facilitator-led and 12 student-led debriefings were analysed. Students gave 682 (49%) contributions in the facilitator-led debriefings, and 702 (51%) contributions in student-led debriefings. Comparison of reflection levels between facilitator-led and student-led debriefings was respectively: R0-level 32.7% vs 33.8%, R1-level 44.0% vs 44.3%, R2-level 14.7% vs 17.1%, R3-level 0.1% vs 1.3%, and R4-level 0.1% vs 0.1%. There were no statistically significant differences in reflection levels between facilitator-led and student-led debriefings (p = 0.178). Comparing the reflection levels between the scenarios on "paediatric emergencies" and "complex assessments", the results were respectively: R0-level 35.4% vs. 31.7%-level, R1-level 45.3% vs. 43.3%-level, R2-level 13.4% vs. 17.8%, R3-level 0.5% vs. 0.9%, and R4-level 0.0% vs. 0.3%. These differences were statistically significant (p = 0.010). No significant differences in engagement were found between debriefings led by a student or a facilitator, when measuring the number of turns in the conversations. CONCLUSIONS: Facilitator-led and student-led debriefings resulted in equivalent reflection levels amongst students. Student-led simulation is potentially a cost-effective supplement to regular simulation within a healthcare degree program. Since complex scenarios provided higher reflection levels than paediatric, scenario design might influence reflection levels.

7.
Nat Rev Rheumatol ; 19(9): 592-602, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37433880

RESUMO

Systemic lupus erythematosus (SLE) is a disease of high unmet therapeutic need. The challenge of accurately measuring clinically meaningful responses to treatment has hindered progress towards positive outcomes in SLE trials, impeding the approval of potential new therapies. Current primary end points used in SLE trials are based on legacy disease activity measures that were neither specifically designed for the clinical trial context, nor developed according to contemporary recommendations for clinical outcome assessments (COAs), such as that substantial patient input should be incorporated into their design. The Treatment Response Measure for SLE (TRM-SLE) Taskforce is a global collaboration of SLE clinician-academics, patients and patient representatives, industry partners and regulatory experts, established to realize the goal of developing a new COA for SLE clinical trials. The aim of this project is a novel COA designed specifically to measure treatment effects that are clinically meaningful to patients and clinicians, and intended for implementation in a trial end point that supports regulatory approval of novel therapeutic agents in SLE. This Consensus Statement reports the first outcomes of the TRM-SLE project, including a structured process for TRM-SLE development.


Assuntos
Lúpus Eritematoso Sistêmico , Humanos , Lúpus Eritematoso Sistêmico/diagnóstico , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Consenso , Avaliação de Resultados em Cuidados de Saúde
9.
Front Microbiol ; 14: 1130018, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37152725

RESUMO

The suomilide and the banyasides are highly modified and functionalized non-ribosomal peptides produced by cyanobacteria of the order Nostocales. These compound classes share several substructures, including a complex azabicyclononane core, which was previously assumed to be derived from the amino acid tyrosine. In our study we were able to isolate and determine the structures of four suomilides, named suomilide B - E (1-4). The compounds differ from the previously isolated suomilide A by the functionalization of the glycosyl group. Compounds 1-4 were assayed for anti-proliferative, anti-biofilm and anti-bacterial activities, but no significant activity was detected. The sequenced genome of the producer organism Nostoc sp. KVJ20 enabled us to propose a biosynthetic gene cluster for suomilides. Our findings indicated that the azabicyclononane core of the suomilides is derived from prephenate and is most likely incorporated by a proline specific non-ribosomal peptide synthetase-unit.

10.
Clin Exp Rheumatol ; 41(3): 543-553, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36916322

RESUMO

Recent studies have shown that people who are immunocompromised may inadvertently play a role in spurring the mutations of the virus that create new variants. This is because some immunocompromised individuals remain at risk of getting COVID-19 despite vaccination, experience more severe disease, are susceptible to being chronically infected and remain contagious for longer if they become infected and considering that immunocompromised individuals represent approximately 2% of the overall population, this aspect should be carefully considered. So far, some autoimmune rheumatic disease (ARD) patients with COVID-19 have been treated with antiviral therapies or anti-SARS-CoV-2 antibody products. However, there is no homogeneous approach to these treatment strategies. This issue was addressed within the European Reference Network (ERN) on Rare and Complex Connective Tissue and Musculoskeletal Diseases (ReCONNET) in a discussion among experts and patient's representatives in the context of the rare and complex connective tissue diseases (rCTDs) covered by the Network. ERN ReCONNET is one of the 24 ERNs launched by the European Commission in 2017 with the aim of tackling low prevalence and rare diseases that require highly specialised treatment and promoting concentration of knowledge and resources through virtual networks involving healthcare providers (HCPs) across the European Union (EU). Considering the urgent need to provide guidance not only to the rCTDs community, but also to the whole ARDs community, a multidisciplinary Task Force, including expert clinicians and European Patient Advocacy Group (ePAG) Advocates, was created in the framework of ERN ReCONNET with the aim of developing overarching principles (OP) and points-to-consider (PtC) on a homogenous approach to treat immunocompromised patients with ARDs (with a particular focus on CTDs) affected by COVID-19 using antiviral therapies and anti-SARS-CoV-2 antibody products. The present work reports the final OP and PtC agreed by the Task Force.


Assuntos
Doenças Autoimunes , COVID-19 , Síndrome do Desconforto Respiratório , Doenças Reumáticas , Humanos , Doenças Autoimunes/tratamento farmacológico , Doenças Reumáticas/tratamento farmacológico , Doenças Reumáticas/epidemiologia , Antivirais/uso terapêutico
12.
Best Pract Res Clin Rheumatol ; 37(4): 101939, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-38485601

RESUMO

Systemic Lupus Erythematosus (SLE) imposes a great burden on the lives of patients. Patients' and physicians' concerns about the disease diverge considerably. Physicians focus on controlling disease activity to prevent damage accrual, while patients focus on symptoms that impact on Health-Related Quality of Life (HRQoL). We explored the physicians' and patients' perspective and the potential role of Patient Reported Outcomes (PROs). Physicians are aware of the theoretical usefulness of PROs to collect information deriving from the patients' perspective. However, they often do not know how to interpret and use these questionnaires in a real shared therapeutic strategy. For the patients, it's important to be seen as a whole person with a true consideration of how they feel and function. Strategies to help bridge the communication gap could include: better use of time during visits, preparing for the consultation, a more understandable lay language used by the doctor, a dedicated nurse.


Assuntos
Comunicação , Lúpus Eritematoso Sistêmico , Medidas de Resultados Relatados pelo Paciente , Relações Médico-Paciente , Qualidade de Vida , Humanos , Lúpus Eritematoso Sistêmico/terapia , Lúpus Eritematoso Sistêmico/psicologia , Lúpus Eritematoso Sistêmico/fisiopatologia , Inquéritos e Questionários
14.
Front Microbiol ; 13: 1005625, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36478870

RESUMO

Actinobacteria are among the most prolific producers of bioactive secondary metabolites. In order to collect Arctic marine bacteria for the discovery of new bioactive metabolites, actinobacteria were selectively isolated during a research cruise in the Greenland Sea, Norwegian Sea and the Barents Sea. In the frame of the isolation campaign, it was investigated how different sample treatments, isolation media and sample-sources, such as animals and sediments, affected the yield of actinobacterial isolates to aid further isolation campaigns. Special attention was given to sediments, where we expected spores of spore forming bacteria to enrich. Beside actinobacteria a high share of bacilli was obtained which was not desired. An experimental protocol for down-scaled cultivation and extraction was tested and compared with an established low-throughput cultivation and extraction protocol. The heat-shock method proved suitable to enrich spore-, or endospore forming bacteria such as bacilli. Finally, a group bioactive compounds could be tentatively identified using UHPLC-MS/MS analysis of the active fractions.

15.
Mar Drugs ; 20(5)2022 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-35621928

RESUMO

Treatment options for infections caused by antimicrobial-resistant bacteria are rendered ineffective, and drug alternatives are needed-either from new chemical classes or drugs with new modes of action. Historically, natural products have been important contributors to drug discovery. In a recent study, the dimeric naphthopyrone lulworthinone produced by an obligate marine fungus in the family Lulworthiaceae was discovered. The observed potent antibacterial activity against Gram-positive bacteria, including several clinical methicillin-resistant Staphylococcus aureus (MRSA) isolates, prompted this follow-up mode of action investigation. This paper aimed to characterize the antibacterial mode of action (MOA) of lulworthinone by combining in vitro assays, NMR experiments and microscopy. The results point to a MOA targeting the bacterial membrane, leading to improper cell division. Treatment with lulworthinone induced an upregulation of genes responding to cell envelope stress in Bacillus subtilis. Analysis of the membrane integrity and membrane potential indicated that lulworthinone targets the bacterial membrane without destroying it. This was supported by NMR experiments using artificial lipid bilayers. Fluorescence microscopy revealed that lulworthinone affects cell morphology and impedes the localization of the cell division protein FtsZ. Surface plasmon resonance and dynamic light scattering assays showed that this activity is linked with the compound's ability to form colloidal aggregates. Antibacterial agents acting at cell membranes are of special interest, as the development of bacterial resistance to such compounds is deemed more difficult to occur.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Antibacterianos/química , Bactérias , Fungos , Bactérias Gram-Positivas , Testes de Sensibilidade Microbiana , Polímeros/farmacologia
16.
Lupus Sci Med ; 9(1)2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35568437

RESUMO

OBJECTIVE: Previous research on coping strategies of patients with SLE showed that there are no absolute adaptive or maladaptive strategies and that the range of potential coping strategies is large and heterogeneous. In this paper, we aimed to identify, in a large sample of patients with SLE (N=3222), the most frequent words used by patients to describe their coping strategies, to group them into significant themes and to test their possible association with specific patient characteristics. METHODS: Our analyses were based on the data set of the European survey 'Living with Lupus in 2020' (N=3222). Through the T-LAB software, we analysed the answers that adult participants gave to an open-ended question about how they cope with the disease. We identified the most frequent words, and with hierarchical cluster analysis we grouped them into semantic clusters (ie, themes) that were characterised by specific patterns of words. Finally, we tested the possible association between clusters and illustrative variables (sociodemographics, disease characteristics, quality of life). RESULTS: Five coping strategies were identified, each of them constituting an important percentage of the total word occurrences: positive attitude (22.58%), social support (25.46%), medical treatments (10.77%), healthy habits (20.74%) and avoid stress (20.45%). Each strategy was statistically associated with specific patient characteristics, such as age and organ involvement. CONCLUSIONS: Learning to adapt to a lifetime of having SLE may require replacing old coping strategies with more effective ones. Investigating patients' coping strategies in relation to different patient characteristics represents a useful starting point for developing more targeted and efficacious interventions.


Assuntos
Lúpus Eritematoso Sistêmico , Adaptação Psicológica , Adulto , Humanos , Lúpus Eritematoso Sistêmico/complicações , Qualidade de Vida , Inquéritos e Questionários
17.
Mar Drugs ; 21(1)2022 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-36662175

RESUMO

Bacterial symbionts of marine invertebrates are rich sources of novel, pharmaceutically relevant natural products that could become leads in combatting multidrug-resistant pathogens and treating disease. In this study, the bioactive potential of the marine invertebrate symbiont Thalassomonas actiniarum was investigated. Bioactivity screening of the strain revealed Gram-positive specific antibacterial activity as well as cytotoxic activity against a human melanoma cell line (A2058). The dereplication of the active fraction using HPLC-MS led to the isolation and structural elucidation of cholic acid and 3-oxo cholic acid. T. actiniarum is one of three type species belonging to the genus Thalassomonas. The ability to generate cholic acid was assessed for all three species using thin-layer chromatography and was confirmed by LC-MS. The re-sequencing of all three Thalassomonas type species using long-read Oxford Nanopore Technology (ONT) and Illumina data produced complete genomes, enabling the bioinformatic assessment of the ability of the strains to produce cholic acid. Although a complete biosynthetic pathway for cholic acid synthesis in this genus could not be determined based on sequence-based homology searches, the identification of putative penicillin or homoserine lactone acylases in all three species suggests a mechanism for the hydrolysis of conjugated bile acids present in the growth medium, resulting in the generation of cholic acid and 3-oxo cholic acid. With little known currently about the bioactivities of this genus, this study serves as the foundation for future investigations into their bioactive potential as well as the potential ecological role of bile acid transformation, sterol modification and quorum quenching by Thalassomonas sp. in the marine environment.


Assuntos
Antibacterianos , Humanos , Ácido Cólico , Filogenia , DNA Bacteriano , Antibacterianos/farmacologia , Análise de Sequência de DNA
18.
Molecules ; 26(24)2021 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-34946641

RESUMO

As part of our search for bioactive metabolites from understudied marine microorganisms, the new chlorinated metabolite chlovalicin B (1) was isolated from liquid cultures of the marine basidiomycete Digitatispora marina, which was collected and isolated from driftwood found at Vannøya, Norway. The structure of the novel compound was elucidated by spectroscopic methods including 1D and 2D NMR and analysis of HRMS data, revealing that 1 shares its molecular scaffold with a previously isolated compound, chlovalicin. This represents the first compound isolated from the Digitatispora genus, and the first reported fumagillin/ovalicin-like compound isolated from Basidiomycota. Compound 1 was evaluated for antibacterial activities against a panel of five bacteria, its ability to inhibit bacterial biofilm formation, for antifungal activity against Candida albicans, and for cytotoxic activities against malignant and non-malignant human cell lines. Compound 1 displayed weak cytotoxic activity against the human melanoma cell line A2058 (~50% survival at 50 µM). No activity was detected against biofilm formation or C. albicans at 50 µM, or against bacterial growth at 100 µM nor against the production of cytokines by the human acute monocytic leukemia cell line THP-1 at 50 µM.


Assuntos
Antibacterianos , Antifúngicos , Bactérias/crescimento & desenvolvimento , Basidiomycota/química , Candida albicans/crescimento & desenvolvimento , Sesquiterpenos , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Antifúngicos/química , Antifúngicos/isolamento & purificação , Antifúngicos/farmacologia , Cicloexanonas/química , Cicloexanonas/isolamento & purificação , Cicloexanonas/farmacologia , Compostos de Epóxi/química , Compostos de Epóxi/isolamento & purificação , Compostos de Epóxi/farmacologia , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação , Sesquiterpenos/farmacologia
19.
Mar Drugs ; 19(11)2021 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-34822511

RESUMO

The marine environment is potentially a prolific source of small molecules with significant biological activities. In recent years, the development of new chromatographic phases and the progress in cell and molecular techniques have facilitated the search for marine natural products (MNPs) as novel pharmacophores and enhanced the success rate in the selection of new potential drug candidates. However, most of this exploration has so far been driven by anticancer research and has been limited to a reduced number of taxonomic groups. In this article, we report a test study on the screening potential of an in-house library of natural small molecules composed of 285 samples derived from 57 marine organisms that were chosen from among the major eukaryotic phyla so far represented in studies on bioactive MNPs. Both the extracts and SPE fractions of these organisms were simultaneously submitted to three different bioassays-two phenotypic and one enzymatic-for cytotoxic, antidiabetic, and antibacterial activity. On the whole, the screening of the MNP library selected 11 potential hits, but the distribution of the biological results showed that SPE fractionation increased the positive score regardless of the taxonomic group. In many cases, activity could be detected only in the enriched fractions after the elimination of the bulky effect due to salts. On a statistical basis, sponges and molluscs were confirmed to be the most significant source of cytotoxic and antimicrobial products, but other phyla were found to be effective with the other therapeutic targets.


Assuntos
Antineoplásicos/farmacologia , Organismos Aquáticos , Animais , Antineoplásicos/química , Fracionamento Químico , Descoberta de Drogas , Moluscos , Poríferos
20.
Front Microbiol ; 12: 730740, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34659158

RESUMO

The emergence of drug-resistant bacteria is increasing rapidly in all parts of the world, and the need for new antibiotics is urgent. In our continuous search for new antimicrobial molecules from under-investigated Arctic marine microorganisms, a marine fungus belonging to the family Lulworthiaceae (Lulworthiales, Sordariomycetes, and Ascomycota) was studied. The fungus was isolated from driftwood, cultivated in liquid medium, and studied for its potential for producing antibacterial compounds. Through bioactivity-guided isolation, a novel sulfated biarylic naphtho-α-pyrone dimer was isolated, and its structure was elucidated by spectroscopic methods, including 1D and 2D NMR and HRMS. The compound, named lulworthinone (1), showed antibacterial activity against reference strains of Staphylococcus aureus and Streptococcus agalactiae, as well as several clinical MRSA isolates with MICs in the 1.56-6.25 µg/ml range. The compound also had antiproliferative activity against human melanoma, hepatocellular carcinoma, and non-malignant lung fibroblast cell lines, with IC50 values of 15.5, 27, and 32 µg/ml, respectively. Inhibition of bacterial biofilm formation was observed, but no eradication of established biofilm could be detected. No antifungal activity was observed against Candida albicans. During the isolation of 1, the compound was observed to convert into a structural isomer, 2, under acidic conditions. As 1 and 2 have high structural similarity, NMR data acquired for 2 were used to aid in the structure elucidation of 1. To the best of our knowledge, lulworthinone (1) represents the first new bioactive secondary metabolite isolated from the marine fungal order Lulworthiales.

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