RESUMO
Pathological mutations in the LRRK2 gene are the major genetic cause of Parkinson's disease (PD). Although several animal models with either LRRK2 down- or over-expression have been developed, the physiological function of LRRK2 remains elusive. LRRK2 is constitutively expressed in various tissues including neurons and glial cells, but importantly, it is expressed at low levels in dopaminergic neurons, further contributing to the cryptic function of LRRK2. Significant levels of LRRK2 protein and mRNA have been detected in peripheral blood mononuclear cells, lymph nodes, the spleen, and primary microglia, strongly suggesting the contribution of inflammatory cells to neuronal degeneration. In this research article, using Drosophila LRRK2 models, we were able to demonstrate a significant contribution of glial cells to the LRRK2 pathological phenotype. Furthermore, in Drosophila, neurodegeneration is associated with a significant and important increase in specific inflammatory peptides. Finally, levetiracetam, a compound widely used in human therapy to treat epilepsy, was able to rescue both neuronal degeneration and neuroinflammation.
RESUMO
In this report, we demonstrate a novel plastic boat capable of selectively and efficiently collecting spilled oils while floating on water. The boat has macroscopic openings in its vertical and curved sidewalls. It is easily, quickly, and inexpensively fabricated using an environmentally friendly polymer via a three-dimensional printing technique. Its surface is sequentially coated with nano-ceramic coating liquid and oil, which imparts favorable hydrophobic, oleophilic, and high oil-wettability properties. Using the boat prototype, a small pump system, and an oil boom-like device, we demonstrate that spilled oils with a wide range of viscosities (2.0-1000 cSt at 25-40 °C) are rapidly collected from the surface of both pure water and seawater. Remarkably, it efficiently collects oil spills on seawater under wavy conditions, and the retrieved oil does not mix with any drop of water. Moreover, the boat can be scaled up to a large size easily and has a long-term usage. By exhibiting these characteristics, our developed boat is a prominent potential device for practical oil retrieval applications.
Assuntos
Poluição por Petróleo , Água , Água/química , Navios , Plásticos , Poluição por Petróleo/análise , Óleos/químicaRESUMO
This paper describes the effective fabrication of an inverse opal (IO) structure for plasmon-induced hyperthermia applications using silver nanoparticles (AgNPs) doped in a conducting polymer of poly(3,4-ethylene dioxythiophene) (PEDOT). Indium tin oxide (ITO) substrates were firstly modified electrochemically by a layer of the inverse opal structure of PEDOT (IO-PEDOT). These as-prepared electrodes were subsequently used as working electrodes for electrodepositing AgNPs. The presence of plasmonic AgNPs doped inside a polymer network caused the hybrid of IO-PEDOT and AgNPs to generate significantly more heat than thin-film PEDOT, thin-film PEDOT/AgNPs, and IO-PEDOT under 532 nm laser irradiation. This is attributed to the synergistic effect of the large active area inverse opal structure and doped AgNPs, which exhibit more thermal energy and heat faster than the individual component structures. These findings point to a wide range of potential applications for hybrid IO-PEDOT/AgNPs in hyperthermia treatment.
RESUMO
Modern fluorescent microscopy imaging is still limited by the optical aberrations and the photon budget available in the specimen. A direct consequence is the necessity to develop flexible and "off-road" algorithms in order to recover structural details and improve spatial resolution, which is critical when restraining the illumination to low levels in order to limit photo-damages. Here, we report SPITFIR(e) a flexible method designed to accurately and quickly restore 2D-3D fluorescence microscopy images and videos (4D images). We designed a generic sparse-promoting regularizer to subtract undesirable out-of-focus background and we developed a primal-dual algorithm for fast optimization. SPITFIR(e) is a "swiss-knife" method for practitioners as it adapts to any microscopy techniques, to various sources of signal degradation (noise, blur), to variable image contents, as well as to low signal-to-noise ratios. Our method outperforms existing state-of-the-art algorithms, and is more flexible than supervised deep-learning methods requiring ground truth datasets. The performance, the flexibility, and the ability to push the spatiotemporal resolution limit of sub-diffracted fluorescence microscopy techniques are demonstrated on experimental datasets acquired with various microscopy techniques from 3D spinning-disk confocal up to lattice light sheet microscopy.
RESUMO
Using various chromatographic separations, two new cembranoids, ehrenbergols F and G (1 and 2), along with three known analogs ehrenbergol D (3), (+)-isosarcophine (4) and sinulariol Z2 (5) were isolated from the soft coral Sarcophyton ehrenbergi. The structural elucidation was done by extensive analysis of the 1 D and 2 D NMR, HR-ESI-QTOF-MS as well as CD experiments. In addition, compounds 1 (IC50 of 38.38 ± 2.89 µM), 3 (IC50 of 37.14 ± 3.22 µM) and 4 (IC50 of 45.01 ± 2.49 µM) revealed moderate inhibitory activity on LPS-induced NO production in RAW264.7 cells, whereas 2 (IC50 of 73.32 ± 1.95 µM) and 5 (IC50 of 64.48 ± 4.93 µM) exhibited weak effect.
Assuntos
Antozoários , Diterpenos , Animais , Antozoários/química , Diterpenos/farmacologia , Diterpenos/química , Espectroscopia de Ressonância Magnética , Estrutura MolecularRESUMO
In our search for cytotoxic constituents from Vietnamese plants, the methanolic extract of Isotrema tadungense was found to exhibit significant cytotoxic effect. Subsequent phytochemical investigation of ethyl acetate fractions of this plant led to isolation of 11 compounds including one new arylbenzofuran rhamnoside namely aristolochiaside (1), two aristololactams (2 and 3), three lignanamides (4-6) and five phenolic amides (7-11). Their structures were elucidated by 1 D and 2 D NMR and HR-QTOF-MS experiments. Among the isolated compounds, aristolochiaside (1), aristolactam AIIIa (2) and N-trans-sinapoyltyramine (10) exhibited strong and selective cytotoxicity on the HeLa human cancer cell line with IC50 values of 7.59 ± 1.03, 8.51 ± 1.73 and 9.77 ± 1.25 µM, respectively.[Formula: see text].
Assuntos
Antineoplásicos , Amidas , Antineoplásicos/farmacologia , Células HeLa , Humanos , Estrutura Molecular , Extratos VegetaisRESUMO
Background and Objectives:Chlamydia spp. are potential zoonotic pathogens that can infect a wide range of animal hosts. In reptiles, Chlamydia can cause hepatitis, pneumonitis, and conjunctivitis and it can cause high mortality in young animals. The objectives of this study were to estimate the pooled prevalence of chlamydial infections in reptiles and to assess the trend of these infections over time. Materials and Methods: The study followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Relevant studies were retrieved from PubMed, Scopus, and Web of Science. The retrieved studies were screened for eligibility. Then, important data were extracted from the included studies. A random effects model was used for all analyses. Subgroup analysis was used to assess heterogeneity for orders of reptiles, continents where the studies were conducted, and types of specimens. Cumulative meta-analysis and meta-regression were used to determine the trend of the prevalence over time. The quality of each included study was evaluated. Results: Of 106 studies (with a total of 2607 samples), 20 met the inclusion criteria and were included in the meta-analysis. The pooled prevalence of chlamydial infections in reptiles was 23.5% (95% confidence interval [CI]: 15.4-34.0). The trend of chlamydial infections increased from 1990 to 2008; thereafter, it was almost stable at slightly over 20%. The most commonly reported Chlamydia spp. were Chlamydia psittaci, Chlamydia pneumoniae, Chlamydia pecorum, and Chlamydia caviae. Among reptiles, the prevalence of chlamydial infections was highest in crocodiles (57.3% [95% CI: 32.5-78.9]). Among continents, the prevalence of chlamydial infections was highest in Australia (68.6% [95% CI: 36.8-89.1]). Conclusions: Based on the included studies, the prevalence of chlamydial infections in reptiles was high, especially in crocodiles. Because C. psittaci and C. pneumoniae are commonly found in reptiles and are well-known zoonotic pathogens, they should be of concern for human health.
Assuntos
Infecções por Chlamydia/veterinária , Chlamydia , Répteis/microbiologia , Animais , Infecções por Chlamydia/epidemiologia , PrevalênciaRESUMO
Aim: Causes, clinical features, and diagnostic approaches for small bowel (SB) bleeding were analyzed to derive recommendations in dealing with this clinical condition. Methods: We included 54 patients undergoing surgical treatment for SB bleeding, from January 2009 to December 2019. Detailed clinical data, diagnosis procedures, and causes of bleeding were collected. Results: Among 54 cases with SB bleeding, the most common causes were tumors (64.8%), followed by angiopathy (14.8%), ulcers (9.3%), diverticula (5.6%), tuberculosis (3.7%), and enteritis (1.9%). Most tumors (32/35 cases, 91.4%) and vascular lesions (8/8 cases, 100%) were located in the jejunum. The incidence of tumors was higher in the older (30/41 cases, 73.1%) than that in patients younger than 40 years of age (5/13 cases, 38.5%, P < 0.01). Common initial findings were melena (68.5%) and hematochezia (31.5%). The overall diagnostic yield of computed tomographic enterography (CTE) was 57.4% (31/54 cases), with the figures for tumors, vascular lesions, and inflammatory lesions being 71.4% (25/35 cases), 62.5% (5/8 cases), and 12.5% (1/8 cases), respectively. Double-balloon enteroscopy (DBE) definitively identified SB bleeding sources in 16/22 (72.7%) patients. Conclusion: Tumors, angiopathy, ulcers, and diverticula were the most common causes of SB bleeding in Northern Vietnamese population. CTE has a high detection rate for tumors in patients with SB bleeding. CTE as a triage tool may identify patients before double-balloon enteroscopy because of the high prevalence of SB tumors.
Assuntos
Enteroscopia de Duplo Balão , Intestino Delgado , Hemorragia Gastrointestinal/epidemiologia , Hemorragia Gastrointestinal/etiologia , Humanos , Intestino Delgado/diagnóstico por imagem , Estudos Retrospectivos , Tomografia Computadorizada por Raios X , VietnãRESUMO
From the MeOH extract of the Vietnamese sea cucumber Holothuria edulis, eight triterpene glycosides (1-8), including one new compound namely holothurin A5 (1), were isolated by using various chromatographic separations. Their structures were established by spectroscopic experiments including 1D, 2D NMR and HR-ESI-MS. Holothurin A5 (1) has a hydroperoxy group at C-25. To the best of our knowledge, this is the first report of this group in triterpene saponins obtained from sea cucumbers to date. In addition, the in vitro cytotoxicity against five human cancer cell lines (HepG2, KB, LNCaP, MCF7 and SK-Mel2) of all isolated compounds was also evaluated using SRB assays.
Assuntos
Glicosídeos/isolamento & purificação , Holothuria/química , Pepinos-do-Mar/química , Triterpenos/isolamento & purificação , Animais , Linhagem Celular Tumoral , Citotoxinas/química , Citotoxinas/isolamento & purificação , Citotoxinas/farmacologia , Glicosídeos/química , Humanos , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Saponinas/química , Saponinas/isolamento & purificação , Triterpenos/química , VietnãRESUMO
Ten briarane-type diterpenoids (1-10), including one new stereoisomer 17-epi-junceellolide B (1), were isolated from the MeOH extract of the Vietnamese gorgonian Junceella fragilis. Their structures were elucidated by spectroscopic experiments including 1D and 2D NMR, and HR-QTOF-MS. In addition, the in vitro cytotoxic activity against eight human cancer cell lines (LNCaP, HepG2, KB, MCF-7, SK-Mel2, HL-60, LU-1 and SW480) of all isolated compounds was evaluated by SRB assays.
Assuntos
Antozoários/química , Antineoplásicos/isolamento & purificação , Diterpenos/isolamento & purificação , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Citotoxinas/química , Citotoxinas/isolamento & purificação , Citotoxinas/farmacologia , Diterpenos/química , Humanos , Estrutura Molecular , Análise Espectral/métodos , VietnãRESUMO
BACKGROUND: Over the last two decades, an innovative technology called Tissue Microarray (TMA), which combines multi-tissue and DNA microarray concepts, has been widely used in the field of histology. It consists of a collection of several (up to 1000 or more) tissue samples that are assembled onto a single support - typically a glass slide - according to a design grid (array) layout, in order to allow multiplex analysis by treating numerous samples under identical and standardized conditions. However, during the TMA manufacturing process, the sample positions can be highly distorted from the design grid due to the imprecision when assembling tissue samples and the deformation of the embedding waxes. Consequently, these distortions may lead to severe errors of (histological) assay results when the sample identities are mismatched between the design and its manufactured output. The development of a robust method for de-arraying TMA, which localizes and matches TMA samples with their design grid, is therefore crucial to overcome the bottleneck of this prominent technology. RESULTS: In this paper, we propose an Automatic, fast and robust TMA De-arraying (ATMAD) approach dedicated to images acquired with brightfield and fluorescence microscopes (or scanners). First, tissue samples are localized in the large image by applying a locally adaptive thresholding on the isotropic wavelet transform of the input TMA image. To reduce false detections, a parametric shape model is considered for segmenting ellipse-shaped objects at each detected position. Segmented objects that do not meet the size and the roundness criteria are discarded from the list of tissue samples before being matched with the design grid. Sample matching is performed by estimating the TMA grid deformation under the thin-plate model. Finally, thanks to the estimated deformation, the true tissue samples that were preliminary rejected in the early image processing step are recognized by running a second segmentation step. CONCLUSIONS: We developed a novel de-arraying approach for TMA analysis. By combining wavelet-based detection, active contour segmentation, and thin-plate spline interpolation, our approach is able to handle TMA images with high dynamic, poor signal-to-noise ratio, complex background and non-linear deformation of TMA grid. In addition, the deformation estimation produces quantitative information to asset the manufacturing quality of TMAs.
Assuntos
Processamento de Imagem Assistida por Computador , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Software , Análise Serial de Tecidos/métodos , Algoritmos , Automação , Simulação por Computador , Bases de Dados Genéticas , Humanos , Microscopia de Fluorescência , Fluxo de TrabalhoRESUMO
Six pregnane steroids including one new compound namely 15ß-hydroxypregna-4,20-dien-3-one (1), were isolated and structurally elucidated from the octocoral Carijoa riisei. The cytotoxic activity against a panel of eight human cancer cell lines of isolated compounds was also evaluated by SRB method. As the results, 18-acetoxypregna-1,4,20-trien-3-one (5) showed significant cytotoxicity against all the tested cell lines with the IC50 values from 22.29 ± 1.47 to 48.73 ± 3.93 µM, whereas 15ß-acetoxypregna-1,4,20-trien-3-one (3) and 20R-acetoxypregna-1,4-dien-3-one (6) only exhibited weak effect on KB cell line with IC50 values of 93.62 ± 7.32 and 71.38 ± 5.45 µM, respectively.
Assuntos
17-alfa-Hidroxipregnenolona/isolamento & purificação , Antozoários/química , Pregnanos/química , Esteroides/química , 17-alfa-Hidroxipregnenolona/química , Animais , Linhagem Celular Tumoral , Humanos , Estrutura Molecular , Pregnanos/isolamento & purificação , Esteroides/isolamento & purificação , VietnãRESUMO
Using various chromatographic separations, six ergostane-type steroids, including one new compound sinubrassione (1), and two pregnene-type steroid glycosides, including one new compound sinubrassioside (7), were isolated from methanol extract of the Vietnamese soft coral Sinularia brassica. The structure elucidation was confirmed by spectroscopic methods including 1D, 2D NMR and HR-ESI-MS. The cytotoxic activities of all the isolated compounds against three human cancer cell lines were also evaluated using MTT-based colorimetric assays.
Assuntos
Antozoários/química , Antineoplásicos , Ergosterol , Glicosídeos/isolamento & purificação , Glicosídeos/farmacologia , Animais , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Ergosterol/análogos & derivados , Ergosterol/química , Ergosterol/isolamento & purificação , Ergosterol/farmacologia , Glicosídeos/química , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , VietnãRESUMO
Eurycoma longifolia is an herbal medicinal plant popularly used in Southeast Asian countries. In the present study, we show that 7-methoxy-(9H-ß-carbolin-1-il)-(E)-1-propenoic acid (7-MCPA), a ß-carboline alkaloid isolated from E. longifolia, exerted anti-inflammatory effects by activating the nuclear factor-E2-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) pathway. 7-MCPA inhibited lipopolysaccharide (LPS)-induced production of nitric oxide (NO), prostaglandin E2 (PGE2 ), and interleukin-6 (IL-6) in RAW264.7 cells and rescued C57BL/6 mice from LPS-induced lethality in vivo. LPS-induced expression of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and IL-6 was also significantly suppressed by treatment of 7-MCPA in RAW264.7 cells. 7-MCPA induced nuclear translocation of Nrf2 and increased transcription of its target genes, such as HO-1. Treating RAW264.7 cells with 7-MCPA increased the intracellular level of reactive oxygen species (ROS) and the phosphorylation level of p38 mitogen-activated protein kinase (MAPK); however, co-treatment with the antioxidant N-acetyl-cysteine (NAC) blocked 7-MCPA-induced p38 MAPK phosphorylation. Moreover, NAC or SB203580 (p38 MAPK inhibitor) blocked 7-MCPA-induced nuclear translocation of Nrf2, suggesting that 7-MCPA activated Nrf2 via a ROS-dependent p38 pathway. 7-MCPA induced HO-1 protein and mRNA expression and knockdown of Nrf2 with siRNA or SB203580 blocked 7-MCPA-mediated induction of HO-1 expression. Inhibiting Nrf2 or HO-1 abrogated the anti-inflammatory effects of 7-MCPA in LPS-stimulated RAW264.7 cells. We also demonstrated that 7-MCPA suppressed LPS-induced nuclear factor κB (NF-κB) activation. These results provide the first evidence that 7-MCPA exerts its anti-inflammatory effect by modulating the Nrf2 and NF-κB pathways and may be a potential Nrf2 activator to prevent or treat inflammatory diseases.
Assuntos
Acrilatos/farmacologia , Anti-Inflamatórios/farmacologia , Carbolinas/farmacologia , Heme Oxigenase-1/metabolismo , Proteínas de Membrana/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Extratos Vegetais/farmacologia , Animais , Sobrevivência Celular/efeitos dos fármacos , Ciclo-Oxigenase 2/metabolismo , Dinoprostona/metabolismo , Avaliação Pré-Clínica de Medicamentos , Eurycoma/química , Interleucina-6/metabolismo , Lipopolissacarídeos/farmacologia , Sistema de Sinalização das MAP Quinases , Camundongos , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Células RAW 264.7 , Transdução de Sinais/imunologiaRESUMO
This study performed phytochemical and bioactive assessments of the mangrove Lumnitzera racemosa Willd. leaves. Bioassay-guided fractionation of the methanolic extracts led to the identification of thirty-six compounds (1-36), their structures were elucidated using detailed NMR spectroscopic and MS analysis. The extracts, fractions, and the isolated compounds were screened for potential antioxidant and cytotoxic activities. Antioxidant assays were performed using peroxyl radical-scavenging and reducing assays, whereas cytotoxicity was measured using MTT assays in HL-60 and Hel-299 cell lines. The methanolic extract, CH2Cl2 and n-BuOH fractions (10.0 µg/mL) exhibited potent antioxidant activity, with Trolox equivalent (TE) values of 24.94 ± 0.59, 28.34 ± 0.20, and 27.09 ± 0.37 (µM), respectively. In addition, the isolated compounds exerted cytotoxic effects in a dose-dependent manner; compounds 1 and 14 exhibited the most potent cytotoxicity in HL-60 cells, with IC50 values of 0.15 ± 0.29 and 0.60 ± 0.16 µM, respectively. To clarify the mechanism(s) behind these cytotoxic effects, we measured the time-dependent changes in apoptotic markers including the condensation and fragmentation of nuclear chromatin, and the downregulation of p-ERK1/2, p-AKT, and c-Myc levels.
Assuntos
Antioxidantes/farmacologia , Combretaceae , Citotoxinas/farmacologia , Extratos Vegetais/farmacologia , Antioxidantes/química , Antioxidantes/isolamento & purificação , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Citotoxinas/química , Citotoxinas/isolamento & purificação , Avaliação Pré-Clínica de Medicamentos/métodos , Células HL-60 , Humanos , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Folhas de PlantaRESUMO
Phytochemical investigation of Kandelia candel resulted in the isolation of six triterpenes (1 - 5) and two glyceryl glycosides (6 and 7) and their structures were determined by comparing the spectroscopic data with those of reported values. In present study, we described the inhibitory effects of fractions and isolated compounds from K. candel on pro-inflammatory cytokines (IL-12 p40, IL-6, and TNF-alpha) production in lipopolysaccharide (LPS) stimulated bone marrow-derived dendritic cells (BMDCs). Results indicated that compounds 3, 6, and 7 showed potent inhibition on IL-6 production (IC50 values at less than 0.5 microM, respectively). Meanwhile, compounds 6 and 7 exhibited strong inhibitory effects on the production of TNF-alpha (IC50 values of 1.7 +/- 0.1 and 5.5 +/- 0.2 microM). Compounds 1 and 3 were also showed the inhibitory effects on IL-12 p40 production (IC50 values of 8.9 +/- 0.4 and 3.3 +/- 0.1 microM, respectively).
Assuntos
Citocinas , Células Dendríticas , Glicosídeos , Interleucina-12 , Interleucina-6 , Rhizophoraceae , Triterpenos , Fator de Necrose Tumoral alfaRESUMO
CONTEXT: A methanol extract of Cyperus rotundus L. (Cyperaceae) rhizomes showed inhibitory activity against α-glucosidase and α-amylase, two enzymes involve in carbohydrate digestion. OBJECTIVE: Identification of compounds from C. rotundus rhizomes responsible for the inhibition of α-glucosidase and α-amylase. MATERIALS AND METHODS: Compounds were identified by a phytochemical investigation using combined chromatographic and spectroscopic methods. α-glucosidase and α-amylase inhibitory activities were evaluated by in vitro enzyme inhibition assays. RESULTS: A new (2RS,3SR)-3,4',5,6,7,8-hexahydroxyflavane (1), together with three known stilbene dimers cassigarol E (2), scirpusin A (3) and B (4) were isolated. Compound 2 inhibited both α-glucosidase and α-amylase activities while the flavane 1 only showed effect on α-amylase, and compounds 3 and 4 were active on α-glucosidase. All four compounds showed significant 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging activity. DISCUSSION: The inhibitory activities against α-amylase and α-glucosidase of the C. rotundus rhizomes were reported for the first time. Stilbene dimers are considered as potent inhibitors of α-glucosidase and promising antihyperglycemic agents. CONCLUSION: The isolated compounds may contribute to the antidiabetic property of C. rotundus.
Assuntos
Cyperus/química , Inibidores de Glicosídeo Hidrolases , Extratos Vegetais/farmacologia , alfa-Amilases/antagonistas & inibidores , Compostos de Bifenilo/química , Inibidores Enzimáticos/química , Inibidores Enzimáticos/isolamento & purificação , Inibidores Enzimáticos/farmacologia , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/isolamento & purificação , Sequestradores de Radicais Livres/farmacologia , Hipoglicemiantes/química , Hipoglicemiantes/isolamento & purificação , Hipoglicemiantes/farmacologia , Picratos/química , Extratos Vegetais/química , RizomaRESUMO
Three new C29 sterols with a cyclopropane ring cyclized between C-26 and C-27 of the side chain, aragusterol I (1), 21-O-octadecanoyl-xestokerol A (4), and 7ß-hydroxypetrosterol (5b), were isolated from the Vietnamese marine sponge Xestospongia testudinaria, along with the known compounds, aragusterol B (2), xestokerol A (3), 7α-hydroxypetrosterol (5a), 7-oxopetrosterol (6), and petrosterol (7). The structures of the new compounds were established by analysis of spectroscopic data including 1D and 2D NMR, and high-resolution electrospray ionization mass spectrometry (HRESIMS). Their capacity to inhibit the adhesion of isolated bacteria from marine biofilms was evaluated against the bacterial strains Pseudoalteromonas sp. D41, Pseudoalteromonas sp. TC8, and Polaribacter sp. TC5. Aragusterol B (2) and 21-O-octadecanoyl-xestokerol A (4) exhibited the most potent antifouling activity with EC50 values close to these reported in the literature for tributyltin oxide, a marine anti-biofouling agent now considered to be a severe marine pollutant. Due to its comparable activity to tributyltin oxide and its absence of toxicity, the new 26,27-cyclosterol, 21-O-octadecanoyl-xestokerol A (4) constitutes a promising scaffold for further investigations.
Assuntos
Incrustação Biológica/prevenção & controle , Esteróis/isolamento & purificação , Esteróis/farmacologia , Xestospongia/química , Animais , Biologia Marinha , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Pseudoalteromonas/efeitos dos fármacos , Esteróis/química , VietnãRESUMO
Two new diterpenes, lobocompactols A (1) and B (2), and five known compounds (3-7) were isolated from the methanol extract of the soft coral Lobophytum compactum using combined chromatographic methods and identified based on NMR and MS data. Each compound was evaluated for cytotoxic activity against A549 (lung) and HL-60 (acute promyelocytic leukemia) human cancer cell lines. Among them, compound 5 exhibited strong cytotoxic activity against the A549 cell line with an IC(50) of 4.97 ± 0.06 µM. Compounds 3, 4, and 7 showed moderate activity with IC(50) values of 23.03 ± 0.76, 31.13 ± 0.08, and 36.45 ± 0.01 µM, respectively. The cytotoxicity of 5 on the A549 cells was comparable to that of the positive control, mitoxantrone (MX). All compounds exhibited moderate cytotoxicity against the HL-60 cell line, with IC(50) values ranging from 17.80 ± 1.43 to 59.06 ± 2.31 µM. Their antioxidant activity was also measured using oxygen radical absorbance capacity method, compounds 1 and 2 exhibiting moderate peroxyl radical scavenging activity of 1.4 and 1.3 µM Trolox equivalents, respectively, at a concentration of 5 µM.