RESUMO
Eugenia flavescens is a species cultivated in Brazil for food purposes. Given the potential application of essential oils from plants of the genus Eugenia, this study was carried out to investigate the chemical composition, acute toxicity, antioxidant, antinociceptive, gastroprotective activities, and possible mechanisms of action of the essential oil from the leaves of E. flavescens (EOEf). The EOEf was extracted by hydrodistillation, and the chemical composition was obtained using gas chromatography-mass spectrometry. The antioxidant activity was evaluated, as well as the acute toxicity and the antinociceptive and anti-inflammatory effects in mice. In addition, the gastroprotective effect was investigated using an acute gastric lesion model, considering possible mechanisms of action. The major components found in the EOEf were guaiol (19.97%), germacrene B (12.53%), bicyclogermacrene (11.11%), and E-caryophyllene (7.53%). The EOEf did not cause signs of toxicity in the acute oral toxicity test and showed in vitro antioxidant activity with IC50 ranging from 247.29 to 472.39 µg/mL in the tests ABTS and DPPH. In the nociceptive test, EOEf showed a 72.05% reduction in nociception at a dose of 100 mg/kg. In evaluating the anti-inflammatory effect, the essential oil inhibited paw edema by 95.50% and 97.69% at doses of 50 and 100 mg/kg. The results showed that EOEf has a gastroprotective effect, acting through the sulfhydryl compounds (-SH), nitric oxide (NO), and synthesis PGE2 pathways. The results suggested that EOEf is a promising source of constituents with antioxidant, antinociceptive, anti-inflammatory, and gastroprotective properties with application in the food and pharmaceutical industries.
Assuntos
Analgésicos , Anti-Inflamatórios , Antioxidantes , Etanol , Eugenia , Inflamação , Óleos Voláteis , Dor , Folhas de Planta , Úlcera Gástrica , Animais , Úlcera Gástrica/tratamento farmacológico , Úlcera Gástrica/induzido quimicamente , Óleos Voláteis/farmacologia , Camundongos , Folhas de Planta/química , Analgésicos/farmacologia , Analgésicos/isolamento & purificação , Antioxidantes/farmacologia , Masculino , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/isolamento & purificação , Dor/tratamento farmacológico , Dor/induzido quimicamente , Eugenia/química , Inflamação/tratamento farmacológico , Brasil , Antiulcerosos/farmacologia , Antiulcerosos/isolamento & purificação , FemininoRESUMO
Syagrus coronata, a native palm tree in the Caatinga domain, produces fixed oil (ScFO) used therapeutically and dietary by Northeast Brazilian communities. This study evaluated its anti-inflammatory potential of CFA-induced arthritis and its effect on behavioral parameters. In the acute model, ScFO at 25, 50, and 100 mg/kg showed edematogenic effects similar to indomethacin at 4 mg/kg (p > 0.05). In the arthritis model, 100 mg/kg ScFO treatment was comparable to indomethacin (4 mg/kg) (p > 0.05). TNF-α and IL-1ß levels were significantly reduced in ScFO-treated groups at 25, 50, and 100 mg/kg, and the indomethacin group (4 mg/kg) versus the positive control (p > 0.05). Radiographs showed severe soft-tissue swelling and bone deformities in the control group, while the 100 mg/kg ScFO group had few alterations, similar to the indomethacin group. Histopathological analysis revealed intense lymphocytic infiltration in the control group, mild diffuse lymphocytic infiltration in the indomethacin group, and mild lymphoplasmacytic infiltration with focal polymorphonuclear infiltrates in the 100 mg/kg ScFO group. Behavioral analysis showed improved exploratory stimuli in ScFO and indomethacin-treated mice compared to the positive control (p > 0.05). ScFO demonstrated anti-inflammatory effects in both acute and chronic arthritis models, reducing edema and pro-inflammatory cytokines, and improved exploratory behavior due to its analgesic properties.
Assuntos
Anti-Inflamatórios , Artrite Experimental , Adjuvante de Freund , Animais , Artrite Experimental/tratamento farmacológico , Artrite Experimental/patologia , Camundongos , Anti-Inflamatórios/farmacologia , Masculino , Óleos de Plantas/farmacologia , Arecaceae/química , Edema/tratamento farmacológico , Fator de Necrose Tumoral alfa/metabolismo , Interleucina-1beta/metabolismo , Óleo de Palmeira/farmacologia , Indometacina/farmacologia , Brasil , Relação Dose-Resposta a DrogaRESUMO
Pseudobombax marginatum, popularly known as "embiratanha," is widely used by traditional communities as anti-inflammatory and analgesic agent. This study aimed to determine the phytochemical profile as well as cytotoxicity, acute oral toxicity, genotoxicity, and mutagenicity attributed to exposure to aqueous (AqEx) and ethanolic (EtEx) extracts of embiratanha bark. Phytochemical screening was conducted using thin-layer chromatography (TLC). Cell viability was analyzed using MTT assay with human mammary gland adenocarcinoma (MDA-MB-231) and macrophage (J774A.1) cell lines, exposed to concentrations of 12.5, 25, 50, or 100 µg/ml of either extract. For acute oral toxicity, comet assay and micronucleus (MN) tests, a single dose of 2,000 mg/kg of either extract was administered orally to Wistar rats. TLC analysis identified classes of metabolites in the extracts, including cinnamic acid derivatives, flavonoids, hydrolyzable tannins, condensed tannins, coumarins, and terpenes/steroids. In the cytotoxicity assay, the varying concentrations of extracts derived from embiratanha induced no significant alterations in the viability of MDA-MB-231 cells. The lowest concentration of EtEx significantly increased macrophage J774A.1 viability. However, the higher concentrations of AqEx markedly lowered macrophage J774A.1 viability. Animals exhibited no toxicity in the parameters analyzed in acute oral toxicity, comet assay, and MN tests. Further, EtEx promoted a significant reduction in DNA damage index and DNA damage frequency utilizing the comet assay, while the group treated with AqEx exhibited no marked differences. Thus, data demonstrated that AqEx or EtEx of embiratanha may be considered safe at a dose of 2,000 mg/kg orgally under our experimental conditions tested.
Assuntos
Extratos Vegetais , Ratos Wistar , Extratos Vegetais/toxicidade , Extratos Vegetais/química , Animais , Humanos , Ratos , Linhagem Celular Tumoral , Masculino , Ensaio Cometa , Testes para Micronúcleos , Feminino , Sobrevivência Celular/efeitos dos fármacos , Compostos Fitoquímicos/toxicidade , Compostos Fitoquímicos/análise , Camundongos , Casca de Planta/química , Mutagênicos/toxicidade , Testes de Mutagenicidade , Etanol/químicaRESUMO
One prominent aspect of Parkinson's disease (PD) is the presence of elevated levels of free radicals, including reactive oxygen species (ROS). Syagrus coronata (S. coronata), a palm tree, exhibits antioxidant activity attributed to its phytochemical composition, containing fatty acids, polyphenols, and flavonoids. The aim of this investigation was to examine the potential neuroprotective effects of S. coronata fixed oil against rotenone-induced toxicity using Drosophila melanogaster. Young Drosophila specimens (3-4 d old) were exposed to a diet supplemented with rotenone (50 µM) for 7 d with and without the inclusion of S. coronata fixed oil (0.2 mg/g diet). Data demonstrated that rotenone exposure resulted in significant locomotor impairment and increased mortality rates in flies. Further, rotenone administration reduced total thiol levels but elevated lipid peroxidation, iron (Fe) levels, and nitric oxide (NO) levels while decreasing the reduced capacity of mitochondria. Concomitant administration of S. coronata exhibited a protective effect against rotenone, as evidenced by a return to control levels of Fe, NO, and total thiols, lowered lipid peroxidation levels, reversed locomotor impairment, and enhanced % cell viability. Molecular docking of the oil lipidic components with antioxidant enzymes showed strong binding affinity to superoxide dismutase (SOD) and glutathione peroxidase (GPX1) enzymes. Overall, treatment with S. coronata fixed oil was found to prevent rotenone-induced movement disorders and oxidative stress in Drosophila melanogaster.
Assuntos
Transtornos dos Movimentos , Rotenona , Animais , Drosophila melanogaster , Simulação de Acoplamento Molecular , Estresse Oxidativo , Antioxidantes/farmacologia , Óxido Nítrico/metabolismoRESUMO
Wounds encompass physical, chemical, biological, induced damages to the skin or mucous membranes. In wound treatment, combating infections is a critical challenge due to their potential to impede recovery and inflict systemic harm on patients. Previously, the essential oil extracted from Psidium glaziovianum (PgEO) demonstrated antinociceptive and anti-inflammatory attributes, along with negligible oral toxicity. Hence, our study aimed to assess the effects of topically applying a gel formulation containing PgEO to excisional wounds in mice. Additionally, an in vitro antimicrobial assessment was conducted. The formulated gel underwent characterization and toxicological evaluation on erythrocytes, as well as a dermal irritation test. Its antimicrobial activity was tested against both gram-positive and gram-negative bacteria, as well as fungi. Subsequently, an assessment of its efficacy in excisional wound healing was conducted in mice. The findings of this investigation highlight the gel's efficacy against both gram-positive and gram-negative bacteria, as well as fungi. Moreover, this study underscores that the PgEO-gel treatment enhances skin wound healing, potentially due to its capacity to trigger antioxidant enzymes and suppress pro-inflammatory cytokines. Furthermore, the gel exhibited minimal toxicity to erythrocytes and skin irritation. These findings hold promise for prospective preclinical and clinical trials across diverse wound types. In conclusion, this study sheds light on the potential therapeutic applications of the gel formulation containing essential oil from P. glaziovianum in the context of wound healing.
Assuntos
Óleos Voláteis , Psidium , Humanos , Animais , Camundongos , Antibacterianos , Estudos Prospectivos , Bactérias Gram-Negativas , Bactérias Gram-Positivas , Cicatrização , Óleos Voláteis/farmacologiaRESUMO
Polysaccharides in plant-exuded gums are complex biopolymers consisting of a wide range of structural variability (linkages, monosaccharide composition, substituents, conformation, chain length and branching). The structural features of polysaccharides confer the ability to be exploited in different industrial sectors and applications involving biological systems. Moreover, these characteristics are attributed to a direct relationship in the process of polysaccharide enzymatic degradation by the fermentative action in the gut microbiota, through intrinsic interactions connecting bacterial metabolism and the production of various metabolites that are associated with regulatory effects on the host homeostasis system. Molecular docking analysis between bacterial target proteins and arabinogalactan-type polysaccharide obtained from gum arabic allowed the identification of intermolecular interactions provided bacterial enzymatic mechanism for the degradation of several arabinogalactan monosaccharide chains, as a model for the study and prediction of potential fermentable polysaccharide. This review discusses the main structural characteristics of polysaccharides from exudate gums of plants and their interactions with the intestinal microbiota.
Assuntos
Microbioma Gastrointestinal , Prebióticos , Simulação de Acoplamento Molecular , Polissacarídeos/química , Gomas Vegetais/química , Plantas/metabolismo , MonossacarídeosRESUMO
Myrciaria floribunda is a plant that is distributed across different Brazilian biomes such as the Amazon, Caatinga, Cerrado, and Atlantic Forest, and it possesses antioxidant, antimicrobial, and anticancer properties. The antinociceptive and anti-inflammatory properties of the essential oil from M. floribunda leaves (MfEO) were examined in this study using mouse models. Gas chromatography-mass spectrometry was employed to describe the oil, and the results revealed that δ-cadinene, bicyclogermacrene, α-cadinol, and epi-α-muurolol predominated in the chemical profile. The oil stimulated a decrease in nociception in the chemical and thermal models used to evaluate acute antinociceptive activity. Findings from the use of pain pathway blockers to study the presumed underlying mechanism indicated opioid pathway activity. The anti-edematogenic effect, decreased cell migration, and generation of pro-inflammatory cytokines provided evidence of the anti-inflammatory potential of the essential oil from M. floribunda. According to this research, the essential oil from M. floribunda can effectively alleviate acute pain and inflammation.
Assuntos
Anti-Infecciosos , Óleos Voláteis , Camundongos , Animais , Óleos Voláteis/farmacologia , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química , Antioxidantes/farmacologia , Anti-Infecciosos/farmacologia , Extratos Vegetais/química , Analgésicos/farmacologia , Analgésicos/química , Folhas de Planta/químicaRESUMO
This study aimed to characterize the phytochemical profile of bark and leaves aqueous extract Commiphora leptophloeos, and conduct in vivo and in vitro assays to determine the presence of any toxicological consequences due to exposure. The phytochemical analysis was carried out using high-performance liquid chromatography (HPLC). The antioxidant activity was estimated utilizing DPPH free radical scavenging and phosphomolybdenum assays. Cell viability was measured by the MTT method on J774 and human adenocarcinoma cells, which were treated with concentrations of 12,5, 25, 50, 100 or 200 µg/ml of both extracts. Acute oral toxicity, genotoxicity, and mutagenicity assays were determined using a single oral dose of 2000 g/kg in male Swiss albino mice (Mus musculus). Biochemical analysis of the blood and histological analyses of the kidneys, liver, spleen, pylorus, duodenum and jejunum were undertaken. Genotoxicity and mutagenicity were determined utilizing blood samples. Gallic acid, catechin, and epicatechin were identified in the bark and chlorogenic acid in leaves. Data demonstrated a high content of phenolic compounds and flavonoids associated with significant antioxidant potential. No significant signs in damage or symptoms of toxicity were detected. No marked reduction in cell viability was found at lower concentrations tested. On histomorphometry, only the gastrointestinal organs exhibited significant difference. Renal hepatic and blood parameters were within the normal range. No apparent signs of toxicity, genotoxicity, mutagenicity or cytotoxicity were found in vivo and in vitro experiments.
Assuntos
Antioxidantes , Catequina , Camundongos , Animais , Masculino , Humanos , Antioxidantes/química , Extratos Vegetais/toxicidade , Extratos Vegetais/química , Commiphora , Casca de Planta/química , Compostos Fitoquímicos/toxicidade , Folhas de Planta/químicaRESUMO
The current trichomoniasis treatment is restrict to 5-nitroimidazole drugs and the emergence of resistant isolates points the need for new therapeutical alternatives. In this study the anti-Trichomonas vaginalis activity of essential oils obtained from Myrtaceae occurring in Caatinga, a plant family with potential antiparasitic activity, was showed. The essential oils varied in their capacity to kill ATCC and fresh clinical T. vaginalis isolates, which was associated with heterogeneity and different patterns of endosymbiosis. Essential oils caused moderate to strong cytotoxicity against mammalian cells, but essential oil of Eugenia pohliana (EOEp) exhibited promising selectivity index towards vaginal epithelial cells. A checkerboard assay revealed a synergistic effect when EOEp and metronidazole were associated, indicating different mechanisms of action. The GC/MS analysis demonstrated the volatile composition of EOEp, with δ-cadinene as majoritary component. This molecule seems to contribute to the trichomonacidal effect and shows potential for the prospection of new antiparasitic compounds.
Assuntos
Eugenia , Myrtaceae , Óleos Voláteis , Trichomonas vaginalis , Animais , Feminino , Óleos Voláteis/química , Antiparasitários/farmacologia , Metronidazol/farmacologia , MamíferosRESUMO
Biosensors are small devices known for their selectivity, high specificity and sensitivity to the respective analyte, at low concentrations. We developed an electrochemical biosensor using the crystalline polymer MOF-[Cu3 (BTC)2 (H2 O)2 ]n to characterize Cratylia mollis seed lectin (Cramoll) and its interaction with free carbohydrate (glucose) and carbohydrates on the surface of rabbit erythrocytes. The electrochemical potentials presented by the exponential curves that vary from 96 to 142â mV in relation to concentrations of 10 to 20â mM of glucose are decisive for the use of the system containing gold electrode/MOF/Cramoll for the characterization of biological models due to its high sensitivity. As well as the kinetic behavior presented in the cyclic voltammograms, with a cathodic current response of 0.000 3â A for a glucose concentration of 15â mM. These results were due to the high specificity of Cramoll under these conditions, promoting stability of surface charges at the Cramoll/electrode interface. This phenomenon facilitates the monitoring of the interaction with free glucose present in the electrolyte medium by potentiometric and amperometric methods and with carbohydrates present on the surface of rabbit erythrocytes through the potentiometric method. Through scanning electron microscopy (SEM) it was possible to observe Cramoll immobilized on the MOF surface, proving the specificity of the ligand (glucose-lectin) through the morphological lectin changes in this process. This electrochemical model, Cramoll/MOF biosensor, is effective for evaluating free lectin/carbohydrate or in the erythrocyte membrane.
Assuntos
Técnicas Biossensoriais , Fabaceae , Animais , Coelhos , Carboidratos/análise , Carboidratos/química , Fabaceae/química , Glucose , Lectinas/química , Sementes/químicaRESUMO
The purpose of this study was to analyses the influence of seasonal variation on the chemical composition and antimicrobial, antioxidant and cytotoxicity activities of the essential oil (EO) extracted from the leaves of Eugenia pohliana. Chemical characterization of the samples - by gas chromatography-mass spectrometry - found 35 and 38 components for summer and winter, respectively, of the EO from E.â pohliana leaves, totaling 47 different compounds. Analysis of antioxidant capacity (DPPH, ABTS and TAC) revealed that the summer EO showed greater free radical scavenging capacity than the winter. Similarly, the summer EO exhibited superior antimicrobial potential (MIC=128-512 µg/mL and MMC=128-1024â µg/mL, compared to the winter EO (128-2048 µg/mL and 256-2048â µg/mL, respectively). Results showed that both oils had a low potential to cause hemolysis. This study provides new scientific evidence on the influence of seasonality on the pharmacological properties of E.â pohliana leaves and its potential for the development of herbal medicines.
Assuntos
Anti-Infecciosos , Eugenia , Óleos Voláteis , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Antioxidantes/química , Radicais Livres , Testes de Sensibilidade Microbiana , Óleos Voláteis/química , Folhas de Planta/química , Estações do AnoRESUMO
Plants of the genus Psidium have been employed in "in natura" consumption and agroindustry, and owing to the diversity of phytochemicals, the development of new pharmaceutical forms has received remarkable research interest. In this study, the essential oil obtained from Psidium glaziovianum (PgEO) leaves were evaluated antinociceptive and anti-inflammatory activities were evaluated in mouse models. Initially, PgEO was characterized by gas chromatography-mass spectrometry and gas chromatography with flame ionization detection, and the profile was dominated by sesquiterpene compounds. In the evaluation of acute antinociceptive activity (abdominal contortions induced by acetic acid, formalin, tail immersion, and hot plate tests), PgEO promoted a reduction in nociception in the chemical and thermal models. Additionally, the potential underlying mechanism was investigated using pain pathway blockers, and the results revealed a combined action of opioidergic and muscarinic pathways. The anti-inflammatory potential was confirmed by anti-edematogenic action, reduced cell migration, pro-inflammatory cytokine production, and granuloma formation in chronic processes. This study provides evidence that PgEO can be effective for the treatment of pain and acute and chronic inflammation.
Assuntos
Óleos Voláteis , Psidium , Administração Oral , Analgésicos , Animais , Edema/induzido quimicamente , Edema/tratamento farmacológico , Inflamação/tratamento farmacológico , Camundongos , Óleos Voláteis/farmacologia , Dor/tratamento farmacológico , Extratos Vegetais , Folhas de Planta/química , Psidium/químicaRESUMO
Polysaccharides are macromolecules with important inherent properties and potential biotechnological applications. These complex carbohydrates exist throughout nature, especially in plants, from which they can be obtained with high yields. Different extraction and purification methods may affect the structure of polysaccharides and, due to the close relationship between structure and function, modify their biological activities. One of the possible applications of these polysaccharides is acting on the skin, which is the largest organ in the human body and can be aged by intrinsic and extrinsic processes. Skincare has been gaining worldwide attention not only to prevent diseases but also to promote rejuvenation in aesthetic treatments. In this review, we discussed the polysaccharides obtained from plants and their innovative potential for skin applications, for example as wound-healing, antimicrobial, antioxidant and anti-inflammatory, antitumoral, and anti-aging compounds.
Assuntos
Antibacterianos/farmacologia , Anti-Inflamatórios/farmacologia , Antineoplásicos/farmacologia , Antioxidantes/farmacologia , Neoplasias/tratamento farmacológico , Polissacarídeos/farmacologia , Envelhecimento/efeitos dos fármacos , Antibacterianos/química , Antibacterianos/isolamento & purificação , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Antioxidantes/química , Antioxidantes/isolamento & purificação , Bactérias/efeitos dos fármacos , Humanos , Plantas Medicinais/química , Polissacarídeos/química , Polissacarídeos/isolamento & purificação , Higiene da Pele , Cicatrização/efeitos dos fármacosRESUMO
Cutaneous Leishmaniasis (CL) is a neglected disease characterized by highest morbidity rates worldwide. The available treatment for CL has several limitations including serious side effects and resistance to the treatment. Herein we aimed to evaluate the activity of essential oil from the peel of Myrciaria floribunda fruits (MfEO) on Leishmania amazonensis. The cytotoxic potential of MfEO on host mammalian cells was evaluated by MTT. The in vitro leishmanicidal effects of MfEO were investigated on the promastigote and intracellular amastigote forms. The ultrastructural changes induced by MfEO were evaluated by Scanning Electron Microscopy (SEM). The molecular docking of the major compounds δ-Cadinene, γ-Cadinene, γ-Muurolene, α-Selinene, α-Muurolene and (E)-Caryophyllene onto the enzymes trypanothione reductase (TreR) and sterol 14-alpha demethylase (C14DM) were performed. Our results showed that MfEO presented moderate cytotoxicity for Vero cells and macrophages. The MfEO inhibited the growth of promastigote and the survival of intracellular amastigotes, in a dose- and time- dependent way. The MfEO presented high selectivity towards amastigote forms, being 44.1 times more toxic for this form than to macrophages. Molecular docking analysis showed that the major compounds of MfEO interact with Leishmania enzymes and that δ-Cadinene (δ-CAD) presented favorable affinity energy values over TreR and C14DM enzymes, when compared with the other major constituents. Molecular dynamics (MD) simulation studies revealed a stable binding of δ-CAD with lowest binding free energy values in MMGBSA assay. Our results suggested that δ-CAD may be a potent inhibitor of TreR and C14DM enzymes. Communicated by Ramaswamy H. Sarma.
Assuntos
Antiprotozoários , Leishmania , Óleos Voláteis , Animais , Chlorocebus aethiops , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Óleos Voláteis/farmacologia , Óleos Voláteis/química , Frutas , Células Vero , Antiprotozoários/química , MamíferosRESUMO
Neglected tropical diseases (NTDs) are a group of pathologies caused by infectious agents or parasites, including the protozoa Leishmania sp. and Trypanosoma cruzi, which cause leishmaniasis and Chagas disease, respectively. The complications of the treatment regimen indicate the urgent need to search for new strategies and therapeutic agents. Among these is the essential oil of Psidium myrsinites DC. The essential oil of the leaves (PMEO) was evaluated in vitro, and cytotoxic activity was analysed against promastigotes of Leishmania braziliensis and Leishmania infantum and epimastigotes of Trypanosoma cruzi, as well as mammalian cells. The results showed that the PMEO had relevant activity against L. braziliensis, low cytotoxicity and a high selectivity index SI = 6.6. These results suggest that PMEO has antiparasitic potential against L. braziliensis, making this species is a possible alternative therapeutic source, given its effectiveness in the in vitro tests performed, opening the possibility of new biological studies in vivo.
Assuntos
Antiprotozoários , Doença de Chagas , Leishmania infantum , Óleos Voláteis , Psidium , Tripanossomicidas , Trypanosoma cruzi , Animais , Antiprotozoários/farmacologia , Doença de Chagas/tratamento farmacológico , Óleos Voláteis/farmacologia , Óleos Voláteis/uso terapêutico , Tripanossomicidas/uso terapêuticoRESUMO
This study reports the development of conjugates based on quantum dots (QD)s and lectins from Schinus terebinthifolia leaves (SteLL) and Punica granatum sarcotesta (PgTeL). Cryptococcus neoformans cells were chosen to evaluate the efficiency of the conjugates. Lectins were conjugated to QDs via adsorption, and the optical parameters (emission and absorption) were monitored. Lectin stability in the conjugates towards denaturing agents was investigated via fluorometry. The conjugation was evaluated using fluorescence microplate (FMA) and hemagglutination (HA) assays. The labeling of the C. neoformans cell surface was quantified using flow cytometry and observed via fluorescence microscopy. The QDs-SteLL and QDs-PgTeL conjugates, obtained at pH 7.0 and 8.0, respectively, showed the maintenance of colloidal and optical properties. FMA confirmed the conjugation, and the HA assay indicated that the lectin carbohydrate-binding ability was preserved after conjugation. SteLL and PgTeL showed stability towards high urea concentrations and heating. Conjugates labeled over 90% of C. neoformans cells as observed via flow cytometry and confirmed through fluorescence microscopy. C. neoformans labeling by conjugates was inhibited by glycoproteins, suggesting specific interactions through the lectin carbohydrate-binding site. Thus, an effective protocol for the conjugation of SteLL or PgTeL with QDs was proposed, yielding new nanoprobes useful for glycobiological studies.
Assuntos
Anacardiaceae/química , Corantes Fluorescentes/química , Lectinas/química , Punica granatum/química , Pontos Quânticos/química , Cryptococcus neoformans , Hemaglutinação , Microscopia de Fluorescência , Nanopartículas/química , Extratos Vegetais/química , Folhas de Planta/químicaRESUMO
The emergence of a new human coronavirus severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has imposed great pressure on the health system worldwide. The presence of glycoproteins on the viral envelope opens a wide range of possibilities for the application of lectins to address some urgent problems involved in this pandemic. In this work, we discuss the potential contributions of lectins from nonmammalian sources in the development of several fields associated with viral infections, most notably COVID-19. We review the literature on the use of nonmammalian lectins as a therapeutic approach against members of the Coronaviridae family, including recent advances in strategies of protein engineering to improve their efficacy. The applications of lectins as adjuvants for antiviral vaccines are also discussed. Finally, we present some emerging strategies employing lectins for the development of biosensors, microarrays, immunoassays and tools for purification of viruses from whole blood. Altogether, the data compiled in this review highlight the importance of structural studies aiming to improve our knowledge about the basis of glycan recognition by lectins and its repercussions in several fields, providing potential solutions for complex aspects that are emerging from different health challenges.
Assuntos
Antivirais/farmacologia , Tratamento Farmacológico da COVID-19 , Metabolismo dos Carboidratos/efeitos dos fármacos , Lectinas/metabolismo , Polissacarídeos/metabolismo , SARS-CoV-2/efeitos dos fármacos , COVID-19/virologia , HumanosRESUMO
This work aimed to investigate the chemical composition, antimicrobial activity, synergistic effect, and structure changes of the essential oil of Hymenaea rubriflora (EOHr). Forty-five constituents were identified in the essential oil, corresponding to 94.43% of the compounds present, being the main components E-Caryophyllene (36.72 ± 1.05%), Germacrene D (16.13 ± 0.31%), α-Humulene (6.06 ± 0.16%), ß-elemene (5.61 ± 0.14%) and δ-Cadinene (3.76 ± 0.07%). Antimicrobial activity was evaluated, presenting antibacterial and antifungal activity with MIC ranging from 0.62 to 40 µL/mL. The essential oil had a synergistic effect when combined with gentamicin and fluconazole. Structural changes were also evaluated and it was possible to observe that EOHr action was related to changes in membrane permeability. The findings obtained here suggest that the use of the essential oil of H. rubriflora in the treatment of infectious diseases presents a potential for the future development of pharmaceutical products.
Assuntos
Anti-Infecciosos , Fabaceae , Hymenaea , Óleos Voláteis , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Testes de Sensibilidade Microbiana , Óleos Voláteis/farmacologiaRESUMO
Egletes viscosa is a plant with therapeutic value due to its antibacterial, antinociceptive and gastroprotective properties. This study aimed to purify, characterize, and evaluate the cytotoxicity of a lectin (EgviL) from the floral capitula of E. viscosa. The lectin was isolated from saline extract through precipitation with ammonium sulfate followed by Sephadex G-75 chromatography. The molecular mass and isoelectric point (pI) of EgviL were determined as well as its temperature and pH stability. Physical-chemical parameters of interaction between EgviL and carbohydrates were investigated by fluorescence quenching and 1H nuclear magnetic resonance (NMR). Cytotoxicity was investigated against human peripheral blood mononuclear cells (PBMCs) and neoplastic cells. EgviL (28.8 kDa, pI 5.4) showed hemagglutinating activity stable towards heating until 60 °C and at the pH range 5.0-7.0. This lectin is able to interact through hydrophobic and electrostatic bonds with galactose and glucose, respectively. EgviL reduced the viability of PBMCs only at the highest concentration tested (100 µg/mL) while was toxic to Jurkat E6-1 cells with IC50 of 24.1 µg/mL,inducing apoptosis. In summary, EgviL is a galactose/glucose-binding protein with acidic character, stable to heating and with cytotoxic effect on leukemic cells.
Assuntos
Antineoplásicos Fitogênicos/farmacologia , Asteraceae/química , Leucócitos Mononucleares/citologia , Lectinas de Plantas/farmacologia , Antineoplásicos Fitogênicos/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Precipitação Química , Estabilidade de Medicamentos , Galactose/metabolismo , Glucose/metabolismo , Testes de Hemaglutinação , Humanos , Interações Hidrofóbicas e Hidrofílicas , Concentração Inibidora 50 , Ponto Isoelétrico , Células Jurkat , Leucócitos Mononucleares/efeitos dos fármacos , Células MCF-7 , Lectinas de Plantas/químicaRESUMO
The partitioning and purification of lectins from the crude extract of Cratylia mollis seeds (Cramoll 1,4) was investigated in aqueous two-phase systems (ATPS). A factorial design model (24) was used to evaluate the influence of polyethylene glycol (PEG) molar mass (1500-8000 g/mol), PEG concentration (12.5-17.5% w/w), phosphate (10-15% w/w) concentration, and pH (6-8) on the differential partitioning, purification factor, and yield of the lectin. Polymer and salt concentration were the most important variables affecting partition of lectin and used to find optimum purification factor by experimental Box-Behnken design together with the response surface methodology (RSM). ATPS showed best conditions composed by 13.9% PEG1500, 15.3% phosphate buffer at pH 6, which ensured purification factor of 4.70. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed a single band of protein with 26.1 kDa. Furthermore, results demonstrated a thermostable lectin presenting activity until 60 °C and lost hemagglutinating activity at 80 °C. According to the obtained data it can be inferred that the ATPS optimization using RSM approach can be applied for recovery and purification of lectins.