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1.
Int J Mol Sci ; 25(1)2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-38203318

RESUMO

Euphorbia species are important sources of polycyclic and macrocyclic diterpenes, which have been the focus of natural-product-based drug research due to their relevant biological properties, including anticancer, multidrug resistance reversal, antiviral, and anti-inflammatory activities. Premyrsinane, cyclomyrsinane, and myrsinane diterpenes are generally and collectively designated as myrsinane-type diterpenes. These compounds are derived from the macrocyclic lathyrane structure and are characterized by having highly oxygenated rearranged polycyclic systems. This review aims to describe and summarize the distribution and diversity of 220 myrsinane-type diterpenes isolated in the last four decades from about 20 Euphorbia species. Some myrsinane diterpenes obtained from Jatropha curcas are also described. Discussion on their plausible biosynthetic pathways is presented, as well as isolation procedures and structural elucidation using nuclear magnetic resonance spectroscopy. Furthermore, the most important biological activities are highlighted, which include cytotoxic and immunomodulatory activities, the modulation of efflux pumps, the neuroprotective effects, and the inhibition of enzymes such as urease, HIV-1 reverse transcriptase, and prolyl endopeptidase, among other biological effects.


Assuntos
Diterpenos , Euphorbia , Jatropha , Diterpenos/farmacologia , Imunomodulação , Prolil Oligopeptidases
2.
Phytochem Rev ; 21(2): 617-646, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35153639

RESUMO

Momordica balsamina L. (Cucurbitaceae), frequently named balsam apple, southern balsam pear or African pumpkin, is a vegetable with high nutritional value, being mostly used as food in sub-Saharan Africa. It has also been largely used in traditional medicine to treat several diseases, such as malaria fevers and diabetes. As a member of the Cucurbitaceae family, the main constituents are cucurbitane-type triterpenoids, with different oxidation patterns, named cucurbitacins. This review aims at summarizing our contribution to the phytochemical study of M. balsamina and the evaluation of the isolated cucurbitacins and derivatives as multidrug resistance reversers in cancer cells and bacteria. In this way, the selective antiproliferative activity against multidrug resistant cancer cells of cucurbitacins obtained from M. balsamina, their ability as P-glycoprotein inhibitors in cancer cells overexpressing this ABC transporter, as well as efflux pump inhibitors in resistant bacteria strains are reviewed. Moreover, the in vitro antimalarial activity of cucurbitacins and acyl derivatives against the blood and liver-stages of Plasmodium strains, and the in vivo activity of selected compounds is also reviewed. Besides our work, edible and medicinal uses, and other studies mainly reporting the biological activities of M. balsamina extracts, such as antidiabetic, antibacterial, anti-inflammatory, and antioxidant properties are also addressed.

3.
Molecules ; 27(9)2022 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-35566076

RESUMO

Broa is a Portuguese maize bread with characteristic sensory attributes that can only be achieved using traditional maize varieties. This study intends to disclose the volatile compounds that are mainly associated with the baking process of broas, which can be important contributors to their aroma. Twelve broas were prepared from twelve maize flours (eleven traditional maize varieties and one commercial hybrid). Their volatile compounds were analyzed by GC×GC-ToFMS (two-dimensional gas chromatography coupled with time-of-flight mass spectrometry) for an untargeted screening of the chemical compounds mainly formed during baking. It was possible to identify 128 volatiles that belonged to the main chemical families formed during this stage. Among these, only 16 had been previously detected in broas. The most abundant were furans, furanones, and pyranones, but the most relevant for the aroma of broas were ascribed to sulfur-containing compounds, in particular dimethyl trisulfide and methanethiol. Pyrazines might contribute negatively to the aroma of broas since they were present in higher amounts in the commercial broa. This work constitutes the most detailed study of the characterization of broas volatile compounds, particularly those formed during the Maillard reaction. These findings may contribute to the characterization of other maize-based foodstuffs, ultimately improving the production of foods with better sensory features.


Assuntos
Compostos Orgânicos Voláteis , Pão/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Humanos , Odorantes/análise , Compostos de Enxofre/análise , Compostos Orgânicos Voláteis/análise , Zea mays/química
4.
J Sci Food Agric ; 102(4): 1422-1429, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-34388265

RESUMO

BACKGROUND: Portugal is one of the main producers of industrial tomato and tomato paste, an important intermediate ingredient used in many added-value foods. The tomato processing industry rigorously selects the fruits by colour during mechanical harvest, picking only completely ripe fruits to produce high quality tomato paste. The latest available data shows that about 1.12 × 108 kg yr-1 of non-red/not-ripe tomatoes are left in the field, representing a major side product/field residue with great impact on the environment and for tomato producers. RESULTS: The aim of the work was to use fermentation by a consortium of yeast and lactic acid bacteria to improve the nutritional quality of unripe tomato paste. A consortium of Lactobacillus plantarum, Leuconostoc mesenteroides and Kluyveromyces marxianus was selected, producing an acidic paste with olive-like flavours after 4 days of fermentation. Nutritional characterization revealed a significant improvement (P < 0.05) in the content of ascorbic acid and antioxidant potential. In addition, ultrahigh-performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) analysis showed that the fermented green tomato paste content in glycoalkaloid α-tomatine represents no hazard to the consumer. CONCLUSION: Therefore, the obtained fermented green tomato paste can be further used to produce new food products, such as salad dressings and sauces. © 2021 Society of Chemical Industry.


Assuntos
Lactobacillales , Solanum lycopersicum , Fermentação , Microbiologia de Alimentos , Valor Nutritivo , Espectrometria de Massas em Tandem
5.
Molecules ; 25(18)2020 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-32947912

RESUMO

The antimicrobial evaluation of twelve natural and hemisynthetic isopimarane diterpenes are reported. The compounds were evaluated against a panel of Gram-positive bacteria, including two methicillin-resistant Staphylococcus aureus (MRSA) strains and one vancomycin-resistant Enterococcus (VRE) strain. Only natural compounds 7,15-isopimaradien-19-ol (1) and 19-acetoxy-7,15-isopimaradien-3ß-ol (6) showed promising results. Isopimarane (1) was the most active, showing MIC values between 6.76 µM against S. aureus (ATCC 43866) and 216.62 µM against E. faecalis (FFHB 427483) and E. flavescens (ATCC 49996). Compound (6) showed moderated activity against all tested microorganisms (MIC between value 22.54 and 45.07 µM). These compounds were found to be active against the methicillin-sensitive strains of S. aureus (CIP 106760 and FFHB 29593), showing MIC values of 13.55 (1) and 22.54 (6) µM. Both compounds were also active against vancomycin-resistant E. faecalis (ATCC 51299) (MIC values of 54.14 and 45.07 µM, respectively). In addition, the cytotoxicity of nine compounds 7,15-isopimaradien-3ß,19-diol (2); mixture: 15-isopimarene-8ß-isobutyryloxy-19-ol and 15-isopimarene-8ß-butyryloxy-19-ol (3); 3ß-acetoxy-7,15-isopimaradiene-19-ol (5); 19-acetoxy-7,15-isopimaradiene-3ß-ol (6); 3ß,19-diacetoxy-7,15-isopimaradiene (8); 15-isopimarene-8ß,19-diol (9); 19-O-ß-d-glucopyranoside-7,15-isopimaradiene (10); lagascatriol-16-O-ß-d-glucopyranoside (11) and lagascatriol-16-O-α-d-mannopyranoside (12) was evaluated in the human breast cancer cell line MDA-MB-231. Isopimarane (2) was the only compound showing some cytotoxicity. The IC50 value of compound (2) was 15 µM, suggesting a mild antiproliferative activity against these breast cancer cells.


Assuntos
Abietanos/química , Anti-Infecciosos/química , Diterpenos/química , Anti-Infecciosos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Diterpenos/farmacologia , Enterococcus faecalis/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Humanos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Relação Estrutura-Atividade , Resistência a Vancomicina/efeitos dos fármacos
6.
Phytochem Anal ; 30(5): 498-511, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31218764

RESUMO

INTRODUCTION: Macrocyclic diterpenes from Euphorbia species were found to be promising modulators of multidrug resistance (MDR), a complex phenomenon that hampers the effectiveness of cancer therapy. OBJECTIVE: To find new effective MDR reversers through the phytochemical study of E. boetica, including isolation and molecular derivatisation. MATERIAL AND METHODS: The phytochemical study of E. boetica was performed through chromatographic techniques. Preliminary analysis of crude chromatographic fractions from the methanol extract was carried out by 1 H-NMR in order to prioritise the study of those having macrocyclic diterpenes. Polyamide resin was used to remove chlorophylls. Molecular derivatisation of isolated compounds comprised hydrolysis, reduction and acylation reactions. The structural identification of compounds was performed through analysis of spectroscopic data, mainly one-dimensional- and two-dimensional-NMR. The MDR reversing activity was assessed using a combination of transport and chemosensitivity assays, in mouse lymphoma (L5178Y-MDR) and Colo320 cell models. RESULTS: The 1 H-NMR study of crude fractions and application of a straightforward method to remove chlorophylls, allowed the effortless isolation of two lathyrane-type diterpenes in large amounts, including the new polyester, euphoboetirane B (1). Taking advantage of the chemical functions of 1, 13 new derivatives were prepared. Several compounds showed to be promising modulators of P-glycoprotein (P-gp), in resistant cancer cells. Most of the compounds tested revealed to interact synergistically with doxorubicin. CONCLUSION: These results corroborate the importance of macrocyclic lathyrane diterpenes as effective lead compounds for the reversal of MDR.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Euphorbia/química , Extratos Vegetais/farmacologia , Animais , Linhagem Celular Tumoral , Humanos , Camundongos , Estrutura Molecular , Extratos Vegetais/química , Análise Espectral/métodos , Relação Estrutura-Atividade
7.
Biofouling ; 34(8): 880-892, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30362371

RESUMO

Glycyrrhiza glabra L. is considered an important source of bioactive compounds. This study aimed at the development of an efficient solution for the treatment of oral candidiasis. Several extracts of Glycyrrhiza glabra L. were prepared using different solvents and their potential in vitro antifungal activity was assessed. Ethanolic extracts showed the most promising results against C. albicans. This extract was incorporated into mucoadhesive nanoparticles (PLA, PLGA and alginate), which were further included in an oral gel, an oral film and a toothpaste, respectively. The results showed that nanoparticles were successfully produced, presenting a mean size among 100-900 nm with high encapsulation efficiency. In vitro studies showed that the most bioadhesive formulation was the oral film with extract-loaded PLGA nanoparticles, followed by the toothpaste with extract-loaded alginate nanoparticles and the oral gel with extract-loaded PLA nanoparticles.


Assuntos
Antifúngicos/farmacologia , Candida albicans/efeitos dos fármacos , Glycyrrhiza/química , Nanoestruturas/química , Extratos Vegetais/farmacologia , Antioxidantes/farmacologia , Formas de Dosagem , Fenômenos Mecânicos , Mucosa Bucal/efeitos dos fármacos , Extratos Vegetais/química
8.
Bioorg Med Chem ; 25(13): 3278-3284, 2017 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-28479022

RESUMO

Macrocyclic diterpenes were previously found to be able to modulate the efflux pump activity of Candida albicans multidrug transporters. Most of these compounds were jatrophanes, but only a few number of lathyrane-type diterpenes was evaluated. Therefore, the aim of this study was to evaluate the ability of nineteen structurally-related lathyrane diterpenes (1-19) to overcome the drug-efflux activity of Cdr1p and Mdr1p transporters of C. albicans, and get some insights on their structure-activity relationships. The transport assay was performed by monitoring Nile Red (NR) efflux in a Saccharomyces cerevisiae strain overexpressing the referred efflux pumps from C. albicans. Moreover, a chemosensitization assay was performed in order to evaluate the type of interaction between the inhibitory compounds and the antifungal drug fluconazole. Compounds 1-13 were previously isolated from Euphorbia boetica or obtained by derivatization, and compounds 14-19 were prepared by chemical transformations of compound 4. In the transport assays, compounds 14-19 revealed the strongest inhibitory activity of the Cdr1p efflux pump, ranging from 65 to 85%. Concerning Mdr1p efflux pump, the most active compounds were 1, 3, 6, 8, and 12 (75-85%). When used in combination with fluconazole, epoxyboetirane K (2) and euphoboetirane N (18) revealed synergistic effects in the AD-CDR1 yeast strain, overexpressing the Cdr1p transporter, through their ability to reduce the effective concentration of the antifungal drug by 23- and 52-fold, respectively.


Assuntos
Antifúngicos/farmacologia , Candida albicans/efeitos dos fármacos , Diterpenos/farmacologia , Proteínas Fúngicas/antagonistas & inibidores , Modelos Biológicos , Saccharomyces cerevisiae/metabolismo , Fatores de Transcrição/antagonistas & inibidores , Antifúngicos/síntese química , Antifúngicos/química , Transporte Biológico/efeitos dos fármacos , Candida albicans/metabolismo , Diterpenos/síntese química , Diterpenos/química , Relação Dose-Resposta a Droga , Proteínas Fúngicas/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Testes de Sensibilidade Microbiana , Estrutura Molecular , Relação Estrutura-Atividade , Fatores de Transcrição/metabolismo
9.
Planta Med ; 82(13): 1180-5, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27145238

RESUMO

Thirteen macrocyclic diterpenes (1-13) of the jatrophane and lathyrane types, either isolated from Euphorbia species or obtained by chemical derivatization, were evaluated for their ability to inhibit the drug efflux activity of Candida albicans CaCdr1p and CaMdr1p multidrug transporters overexpressed in a Saccharomyces cerevisiae strain. Their inhibitory potential was assessed through a functional assay of Nile Red accumulation monitored by flow cytometry. A chemosensitization assay, using the checkerboard method, was also performed with the active compounds in order to evaluate their type of interaction with fluconazole.In the transport assay, most compounds were found to inhibit both transporters, most likely as non-substrates, as shown by relative resistance indices close to unity. In contrast, the jatrophanes euphopubescenol (10) and euphomelliferene A (11) were selective for CaMdr1p and CaCdr1p, respectively. Moreover, when used in combination with fluconazole, compounds 12 and 13 displayed strong synergistic interactions (FICI = 0.071) against the yeast strain overexpressing CaMdr1p, decreasing the MIC80 of the antifungal agent 13-fold. Both compounds were also able to reduce the effective concentration of this antifungal agent by 4- to 8-fold against an azole-resistant clinical isolate of C. albicans (F5).


Assuntos
Antifúngicos/farmacologia , Candida albicans/efeitos dos fármacos , Diterpenos/farmacologia , Farmacorresistência Fúngica Múltipla , Euphorbia/química , Proteínas de Membrana Transportadoras/efeitos dos fármacos , Extratos Vegetais/farmacologia , Antifúngicos/isolamento & purificação , Diterpenos/isolamento & purificação , Testes de Sensibilidade Microbiana
10.
J Nat Prod ; 78(9): 2215-28, 2015 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-26331763

RESUMO

Epoxyboetirane A (1), a macrocyclic diterpene that was found to be inactive as an ABCB1 modulator, was submitted to several chemical transformations, aimed at generating a series of compounds with improved multidrug resistance (MDR)-modifying activity. Overall, 23 new derivatives were prepared, in addition to the already reported epoxylathyrol (2) and methoxyboetirol (3). Their anti-MDR potential was assessed through both functional and chemosensitivity assays on resistant human colon adenocarcinoma and human ABCB1-gene transfected L5178Y mouse lymphoma cells. Structure-activity relationship analysis showed that different substitution patterns led to distinct ABCB1 inhibitory activities, although intrinsic cellular characteristics seemed to influence the modulatory behavior. A considerable enhancement in MDR-modifying activity was observed for aromatic compounds in both cell lines, particularly in 3,17-disubstituted esters derived from 3, a Payne-rearranged Michael adduct of 2. All compounds tested were revealed to interact synergistically with doxorubicin, and ATPase inhibition by three representative MDR-modifying compounds was also investigated. On account of its outstanding ABCB1 inhibitory activity at 0.2 µM and overall remarkable bioactive profile, methoxyboetirane B (22) was found to be a new promising lead for MDR-reversing anticancer drug development.


Assuntos
Antineoplásicos/isolamento & purificação , Diterpenos/isolamento & purificação , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Euphorbia/química , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Adenocarcinoma , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Neoplasias do Colo/patologia , Técnicas de Química Combinatória , Diterpenos/química , Diterpenos/farmacologia , Doxorrubicina/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Humanos , Linfoma de Células T , Camundongos , Estrutura Molecular , Relação Estrutura-Atividade
11.
Bioorg Med Chem ; 22(22): 6392-400, 2014 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-25438763

RESUMO

Aiming to optimize macrocyclic lathyrane-type diterpenes as effective Pgp modulators, the phytochemical study of the methanolic extract of Euphorbia boetica aerial parts was carried out. Two new macrocyclic 6,17-epoxylathyrane-type diterpenes, named epoxyboetiranes A (1) and B (2), along with three known analogues (3-5) were isolated. Epoxyboetirane A (1), a triacetate isolated in large amounts, was hydrolyzed to give epoxylathyrol (6). In order to study the effect of the substitution pattern of the macrocyclic scaffold on MDR reversal, 6 was acylated with aroyl, phenylacetyl, cinnamoyl and alkanoyl chlorides/anhydrides, yielding eight new esters, epoxyboetiranes C-J (7-14). The ability of compounds 1-14 as P-glycoprotein (Pgp, ABCB1) modulators was evaluated through combination of transport and chemosensitivity assays, using L5178Y mouse T lymphoma cell line transfected with the human MDR1 gene. In the transport assay, excepting 1, 3 and 6, the compounds, at non-cytotoxic concentrations, displayed strong MDR reversing activity in a dose-dependent mode, exhibiting all the new acyl derivatives (7-14) a many fold increase in the activity when compared with 1. Apart from 11 and 12, all compounds exhibited remarkable synergistic effects in combination with doxorubicin. An ATPase assay, using membrane vesicles from mammalian cells overexpressing Pgp, was also performed with two representatives of the modulators (4 and 5). The results suggest that both compounds compete with substrates for the Pgp drug-binding sites.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Diterpenos/química , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/química , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Animais , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Diterpenos/isolamento & purificação , Diterpenos/farmacologia , Euphorbia/química , Euphorbia/metabolismo , Humanos , Camundongos , Componentes Aéreos da Planta/química , Componentes Aéreos da Planta/metabolismo , Rodaminas/química , Rodaminas/metabolismo
12.
Life (Basel) ; 13(7)2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37511889

RESUMO

Rheumatoid arthritis (RA) is a chronic autoimmune inflammatory disease characterized by joint inflammation, swelling and pain. Although RA mainly affects the joints, the disease can also have systemic implications. The presence of autoantibodies, such as anti-cyclic citrullinated peptide antibodies and rheumatoid factors, is a hallmark of the disease. RA is a significant cause of disability worldwide associated with advancing age, genetic predisposition, infectious agents, obesity and smoking, among other risk factors. Currently, RA treatment depends on anti-inflammatory and disease-modifying anti-rheumatic drugs intended to reduce joint inflammation and chronic pain, preventing or slowing down joint damage and disease progression. However, these drugs are associated with severe side effects upon long-term use, including immunosuppression and development of opportunistic infections. Natural products, namely triterpenes with anti-inflammatory properties, have shown relevant anti-arthritic activity in several animal models of RA without undesirable side effects. Therefore, this review covers the recent studies (2017-2022) on triterpenes as safe and promising drug candidates for the treatment of RA. These bioactive compounds were able to produce a reduction in several RA activity indices and immunological markers. Celastrol, betulinic acid, nimbolide and some ginsenosides stand out as the most relevant drug candidates for RA treatment.

13.
Pharmaceuticals (Basel) ; 17(1)2023 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-38256888

RESUMO

Arthritis is a major cause of disability. Currently available anti-arthritic drugs, such as disease-modifying anti-rheumatic drugs (DMARDs), have serious side-effects associated with long-term use. Triterpenoids are natural products with known anti-inflammatory properties, and many have revealed efficiency against arthritis both in vitro and in vivo in several animal models, with negligible cytotoxicity. However, poor bioavailability due to low water solubility and extensive metabolism upon oral administration hinder the therapeutic use of anti-arthritic triterpenoids. Therefore, drug delivery systems (DDSs) able to improve the pharmacokinetic profile of triterpenoids and achieve sustained drug release are useful alternatives for targeted delivery in arthritis treatment. Several DDSs have been described in the literature for triterpenoid delivery, including microparticulate and nanoparticulate DDSs, such as polymeric micro and nanoparticles (NPs), polymeric micelles, liposomes, micro and nanoemulsions, and hydrogels. These systems have shown superior therapeutic effects in arthritis compared to the free drugs and are similar to currently available anti-arthritic drugs without significant side-effects. This review focuses on nanocarriers for triterpenoid delivery in arthritis therapy, including osteoarthritis (OA), rheumatoid arthritis (RA) and gout that appeared in the literature in the last ten years.

14.
Animals (Basel) ; 13(17)2023 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-37684980

RESUMO

A placebo-controlled study evaluated the clinical efficacy and safety of a commercially available cannabidiol (CBD) oral formulation as an adjunctive treatment for pain management for feline chronic gingivostomatitis (FCGS). CBD was included in a multimodal treatment routinely performed on client-owned cats with FCGS that were submitted to dental extractions. Twenty-two cats were consecutively included in the study. The first group was treated using a fixed dosage of 4 mg per cat every 12 h for 15 consecutive days, and the second received a placebo of similar features. Treatments began 2 h before dental extractions. Pain and disease severity were assessed at days 0 and 15 using the Composite Oral Pain Scale (COPS-C/F) and the Stomatitis Disease Activity Index score (SDAI). Weight, vital and biochemistry parameters, and analgesic reinforcement needs were also registered at the same time points. In the treated cats, blood was collected after 4, 8, and 12 h to determine CBD serum concentrations using ultra-high-performance liquid chromatography-mass spectrometry (UHPLC-MS/MS). After data analysis using mixed models, a significant improvement in the SDAI scores of cats medicated with CBD was found. The protocol is safe since severe adverse effects and biochemical changes were not observed during the treatment period. This study suggests that the cats benefited from this treatment.

15.
Colloids Surf B Biointerfaces ; 230: 113486, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37572399

RESUMO

Infections associated with the surfaces of medical devices represent a critical problem due to biofilm formation and the growing resistance towards antibacterial drugs. This is particularly relevant in commonly used invasive devices such as silicone-based ones where a demand for alternative antibiofilm surfaces is increasing. In this work, an antimicrobial chitosan-biosurfactant hydrogel mesh was produced by 3D-printing. The 3D structure was designed to coat polydimethylsiloxane-based medical devices for infection prevention. Additionally, the porous 3D structure allows the incorporation of customized bioactive components. For this purpose, two biosurfactants (surfactin and sophorolipids) were biosynthesized and tested for their antimicrobial activity. In addition, the printing of surfactant-chitosan-based coatings was optimized, and the resulting 3D structures were characterized (i.e., wettability, FTIR-ATR, antimicrobial activity, and biocompatibility). Compared with surfactin, the results showed a better yield and higher antibacterial activity against Gram-positive bacteria for sophorolipids (SLs). Thus, SLs were used to produce chitosan-based 3D-printed coatings. Overall, the SLs-impregnated coatings showed the best antibacterial activity against Staphylococcus aureus planktonic bacteria (61 % of growth inhibition) and antibiofilm activity (2 log units reduction) when compared to control. Furthermore, concerning biocompatibility, the coatings were cytocompatible towards human dermal fibroblasts. Finally, the coating presented a mesh suitable to be filled with a model bioactive compound (i.e., hyaluronic acid), paving the way to be used for customized therapeutics.


Assuntos
Anti-Infecciosos , Quitosana , Humanos , Silicones/química , Quitosana/farmacologia , Quitosana/química , Antibacterianos/farmacologia , Antibacterianos/química , Staphylococcus aureus , Impressão Tridimensional , Materiais Revestidos Biocompatíveis/química , Biofilmes
16.
J Nat Prod ; 75(11): 1915-21, 2012 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-23098168

RESUMO

Three new macrocyclic jatrophane diterpenes, named euphomelliferine (1) and euphomelliferenes A (2) and B (3), and one new tetracyclic triterpene, 19(10→9)-abeo-8α,9ß,10α-tirucalla-5,25-diene-3ß,24-diol (6, C-24 epimers), were isolated from the methanolic extract of Euphorbia mellifera. A known ingenane (7) and two jatrophane diterpenes (4 and 5) were also isolated. Their structures were elucidated by extensive spectroscopic methods, including 1D and 2D homo- and heteronuclear NMR experiments. Jatrophane diterpenes 1-3 and 5 were evaluated for their effects on the reversion of multidrug resistance (MDR) mediated by P-glycoprotein, by using the rhodamine-123 exclusion test, on human MDR1 gene-transfected mouse lymphoma cells (L5178Y MDR) and on human colon adenocarcinoma cells (COLO 320). The apoptosis-inducing activity of these compounds was also tested on COLO 320 cells, using the annexin-V/propidium iodide assay. Diterpenes 1 and 2 displayed significant MDR reversing activity, in a dose-dependent manner, on both cancer cell models. The tested compounds did not induce apoptosis in the COLO 320 cells.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/farmacologia , Neoplasias do Colo/tratamento farmacológico , Diterpenos/isolamento & purificação , Diterpenos/farmacologia , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Euphorbia/química , Triterpenos/isolamento & purificação , Triterpenos/farmacologia , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/efeitos dos fármacos , Algoritmos , Animais , Apoptose/efeitos dos fármacos , Diterpenos/química , Humanos , Camundongos , Estrutura Molecular , Portugal , Triterpenos/química , Células Tumorais Cultivadas
17.
J Nat Prod ; 75(11): 1896-902, 2012 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-23137376

RESUMO

Multidrug resistance (MDR) of cancer cells constitutes one of the main reasons for chemotherapy failure. The search for nontoxic modulators that reduce MDR is a task of great importance. An ability to enhance apoptosis of resistant cells would also be beneficial. In the present study, the MDR reversal and apoptosis-inducing potency of three flavonoids produced by Citrus plants, namely, naringenin (1a), aromadendrin (2), and tangeretin (3), and the methylated naringenin derivatives (1b, 1c), have been studied in sensitive (LoVo) and multidrug-resistant (LoVo/Dx) human colon adenocarcinoma cells. Cytotoxicity of methoxylated flavonoids was higher as compared to hydroxylated analogues. Only 3 turned out to inhibit P-glycoprotein, as demonstrated by a rhodamine 123 accumulation assay. It also increased doxorubicin accumulation in LoVo/Dx cells and enabled doxorubicin to enter cellular nuclei. In addition, 3 was found to be an effective MDR modulator in resistant cells by sensitizing them to doxorubicin. Tangeretin-induced caspase-3 activation and elevated surface phosphatidylserine exposure demonstrated its apoptosis-inducing activity in LoVo/Dx cells, while the other flavonoids evaluated were not active. Additionally, 3 was more toxic to resistant rather than to sensitive cancer cells. Its apoptosis-inducing activity was also higher in LoVo/Dx than in LoVo cells. It was concluded that the activity of 3 against multidrug-resistant cancer cells may be enhanced by its apoptosis-inducing activity.


Assuntos
Apoptose/efeitos dos fármacos , Citrus/química , Neoplasias do Colo/tratamento farmacológico , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Flavonoides/isolamento & purificação , Flavonoides/farmacologia , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/efeitos dos fármacos , Algoritmos , Caspase 3/efeitos dos fármacos , Caspase 3/metabolismo , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Flavanonas/química , Flavanonas/uso terapêutico , Flavonas/química , Flavonas/uso terapêutico , Flavonoides/química , Flavonoides/uso terapêutico , Humanos , Estrutura Molecular , Rodamina 123/análise
18.
Planta Med ; 78(2): 148-53, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22002848

RESUMO

Two new 2-arylbenzofuran neolignans and a new benzophenanthridine alkaloid, together with six known benzophenanthridine alkaloids, namely, decarine, norchelerythrine, dihydrochelerythrine, 6-acetonyldihydrochelerythrine, tridecanonchelerythrine, and 6-acetonyldihydronitidine, have been isolated from the MeOH extract of the roots of Zanthoxylum capense. Their structures were elucidated by means of spectroscopic techniques including 2D NMR experiments. All the isolated compounds were evaluated for their in vitro antibacterial activity against gram-positive and gram-negative bacteria. Some compounds showed significant inhibitory activity against Staphylococcus aureus ATCC 6538 with MIC values ranging from 12.5 to 50 µg/mL.


Assuntos
Alcaloides/farmacologia , Antibacterianos/farmacologia , Benzofenantridinas/farmacologia , Extratos Vegetais/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Zanthoxylum/química , Alcaloides/isolamento & purificação , Antibacterianos/química , Antibacterianos/isolamento & purificação , Bactérias/efeitos dos fármacos , Benzofenantridinas/isolamento & purificação , Testes de Sensibilidade Microbiana , Estrutura Molecular , Extratos Vegetais/química , Raízes de Plantas/química
19.
Pharmaceuticals (Basel) ; 15(10)2022 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-36297361

RESUMO

For centuries, nature has been an inspirational source for the discovery of traditional remedies and drugs used in modern medicine [...].

20.
Pharmaceuticals (Basel) ; 15(3)2022 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-35337138

RESUMO

Human African trypanosomiasis (sleeping sickness) and American trypanosomiasis (Chagas disease) are vector-borne neglected tropical diseases, caused by the protozoan parasites Trypanosoma brucei and Trypanosoma cruzi, respectively. These diseases were circumscribed to South American and African countries in the past. However, human migration, military interventions, and climate changes have had an important effect on their worldwide propagation, particularly Chagas disease. Currently, the treatment of trypanosomiasis is not ideal, becoming a challenge in poor populations with limited resources. Exploring natural products from higher plants remains a valuable approach to find new hits and enlarge the pipeline of new drugs against protozoal human infections. This review covers the recent studies (2016-2021) on plant terpenoids, and their semi-synthetic derivatives, which have shown promising in vitro and in vivo activities against Trypanosoma parasites.

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