RESUMO
Every food source contains both edible and inedible waste components. Millions of tonnes of trash from the food business are made from fruits, and these wastes are containing higher-value medicinal components, such as alkaloids, flavonoids, phenolic contents, a huge amount of proteins and secondary metabolites. These bioactive phytoconstituents are being used for the treatment of many serious fatal diseases. So, utilizing the recovered bioactive molecules from food wastes as functional ingredients offers a long-term alternative source of therapeutically active components that will lead to the discovery of novel phytoconstituents or novel treatment approaches. The goal of this systematic study is to provide an overview of the jackfruit (Artocarpus heterophyllus Lam, Moraceae) edible byproducts, such as jackfruit seeds that are largely neglected. This seed contains numerous bioactive lead molecules, such as carbohydrate-binding protein jacalin, which exhibits potent anticancer activity against colon cancer, blood cancer and breast cancer as well as can enlighten the new possible treatment approaches in targeted therapy and photodynamic chemotherapy. Moreover, jackfruit waste seed can be taken as a dietary food, which is having property to prevent and treat cancer and other lifestyle diseases. The works that have been carried out to utilize jackfruit waste other than the juicy edible bulbs have been reviewed in this article.
Assuntos
Artocarpus , Lectinas , Humanos , Lectinas/análise , Lectinas/química , Artocarpus/química , Lectinas de Plantas/análise , Sementes/químicaRESUMO
The highly glycosylated spike protein of SARS-CoV-2 is essential for infection and constitutes a prime target for antiviral agents and vaccines. The pineapple-derived jacalin-related lectin AcmJRL is present in the medication bromelain in significant quantities and has previously been described to bind mannosides. Here, we performed a large ligand screening of AcmJRL by glycan array analysis, quantified the interaction with carbohydrates and validated high-mannose glycans as preferred ligands. Because the SARS-CoV-2 spike protein was previously reported to carry a high proportion of high-mannose N-glycans, we tested the binding of AcmJRL to the recombinantly produced extraviral domain of spike protein. We could demonstrate that AcmJRL binds the spike protein with a low-micromolar KD in a carbohydrate-dependent fashion.
Assuntos
Ananas , Lectinas , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Ananas/química , Carboidratos , Lectinas/química , Manose/química , Polissacarídeos/química , Ligação Proteica , Glicoproteína da Espícula de Coronavírus/químicaRESUMO
This study evaluated the effects of acute exposure of Aedes aegypti third instar (L3 ) larvae to the saline extract of Opuntia ficus-indica cladodes on the biological cycle and fertility of the emerging adults. For this, larvae were treated for 24 h with the extract at » LC50 (lethal concentration to kill 50% of larvae), ½ LC50 or LC50 ; the development and reproduction of the emerged adults were evaluated after a recovery period of 9 days. The resistance of proteins in the extract to hydrolysis by L3 digestive enzymes and histomorphological alterations in the larval midgut were also investigated. The extract contained lectin, flavonoids, cinnamic derivatives, terpenes, steroids, and reducing sugars. It showed a LC50 of 3.71% for 48 h. The data indicated mean survival times similar in control and extract treatments. It was observed development delay in extract-treated groups, with a lower number of adults than in control. However, the females that emerged laid similar number of eggs in control and treatments. Histological evaluation revealed absence of bacterial and fungal microorganisms in the food content in midguts from larvae treated with cladode extract. Electrophoresis revealed that three polypeptides in the extract resisted to hydrolysis by L3 digestive proteases for 90 min. The lectin activity was not altered even after 24-h incubation with the enzymes. In conclusion, the extract from O. ficus-indica can delay the development of Ae. aegypti larvae, which may be linked to induction of an axenic environment at larval midgut and permanence of lectin activity even after proteolysis.
Assuntos
Aedes , Inseticidas , Opuntia , Feminino , Animais , Lectinas/química , Larva , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Inseticidas/farmacologiaRESUMO
The ability to reversibly bind carbohydrates is an incredible property from lectins. Such characteristic has led these molecules to be employed in several applications involving medical research and biotechnology. Generally, these proteins follow several steps towards purification. Here, the synthesis, physical characterization, and use of levan-coated magnetite nanoparticles (MNPs-levan) for lectin isolation is described. Canavalia ensiformis and Cratylia mollis were used as sources of Concanavalin A and Cramoll, respectively, that were purified by using MNPs-levan. Mass spectrometry, SDS-PAGE, and hemagglutinating activity were employed to assess the efficiency of the process. Moreover, by using mass spectrometry approaches, a novel lectin, similar to Canavalin, was also identified for C. mollis, corroborating the advantages of using nanoparticles over microparticles. MNPs-levan could also be recycled, making this a low-cost, scalable process that can be efficiently employed over crude samples.
Assuntos
Fabaceae , Nanopartículas de Magnetita , Fabaceae/química , Óxido Ferroso-Férrico , Frutanos , Lectinas/análise , Lectinas/química , Extratos Vegetais/análise , Lectinas de Plantas/química , Plantas/metabolismo , Sementes/químicaRESUMO
A glycoprotein (MGP2) from mountain-cultivated ginseng (MCG) was purified by Tris-HCl extraction followed by DEAE-52 ion exchange chromatography and Sephadex G-100 gel filtration chromatography. The approximate molecular weight (27.0 kDa) and monomeric nature were determined by reduced and non-reduced SDS-PAGE. The structure of MGP2 was characterized by a practical and reliable "protein-polysaccharide analyzed by spectroscopy combined with chemical analysis" strategy. The results showed that MGP2 belonged to Arabinogalactan proteins (AGPs) which contained high amount of Glc (35.1 %). The hemagglutination test concluded that MGP2 was not a lectin. In addition, the MGP2 exhibited antioxidant activity by scavenging radical capacity tests and the ability to protect human erythrocytes and RAW264.7 cells from oxidative damage induced by AAPH. Therefore, these results suggested that glycoprotein MGP2 could be used as a natural antioxidant in drug and food industry.
Assuntos
Panax , Antioxidantes/farmacologia , Cromatografia por Troca Iônica , Glicoproteínas/farmacologia , Humanos , Lectinas/química , Peso Molecular , Panax/químicaRESUMO
Lectins are proteins with a remarkably high affinity and specificity for carbohydrates. Many organisms naturally produce them, including animals, plants, fungi, protists, bacteria, archaea, and viruses. The present report focuses on lectins produced by marine or freshwater organisms, in particular algae and cyanobacteria. We explore their structure, function, classification, and antimicrobial properties. Furthermore, we look at the expression of lectins in heterologous systems and the current research on the preclinical and clinical evaluation of these fascinating molecules. The further development of these molecules might positively impact human health, particularly the prevention or treatment of diseases caused by pathogens such as human immunodeficiency virus, influenza, and severe acute respiratory coronaviruses, among others.
Assuntos
Antibacterianos/farmacologia , Cianobactérias , Lectinas/farmacologia , Microalgas , Extratos Vegetais/farmacologia , Animais , Antibacterianos/química , Organismos Aquáticos , Lectinas/química , Extratos Vegetais/química , Relação Estrutura-AtividadeRESUMO
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
Lectin-glycan interactions facilitate inter- and intracellular communication in many processes including protein trafficking, host-pathogen recognition, and tumorigenesis promotion. Specific recognition of glycans by lectins is also the basis for a wide range of applications in areas including glycobiology research, cancer screening, and antiviral therapeutics. To provide a better understanding of the determinants of lectin-glycan interaction specificity and support such applications, this study comprehensively investigates specificity-conferring features of all available lectin-glycan complex structures. Systematic characterization, comparison, and predictive modeling of a set of 221 complementary physicochemical and geometric features representing these interactions highlighted specificity-conferring features with potential mechanistic insight. Univariable comparative analyses with weighted Wilcoxon-Mann-Whitney tests revealed strong statistical associations between binding site features and specificity that are conserved across unrelated lectin binding sites. Multivariable modeling with random forests demonstrated the utility of these features for predicting the identity of bound glycans based on generalized patterns learned from non-homologous lectins. These analyses revealed global determinants of lectin specificity, such as sialic acid glycan recognition in deep, concave binding sites enriched for positively charged residues, in contrast to high mannose glycan recognition in fairly shallow but well-defined pockets enriched for non-polar residues. Focused fine specificity analysis of hemagglutinin interactions with human-like and avian-like glycans uncovered features representing both known and novel mutations related to shifts in influenza tropism from avian to human tissues. As the approach presented here relies on co-crystallized lectin-glycan pairs for studying specificity, it is limited in its inferences by the quantity, quality, and diversity of the structural data available. Regardless, the systematic characterization of lectin binding sites presented here provides a novel approach to studying lectin specificity and is a step towards confidently predicting new lectin-glycan interactions.
Assuntos
Lectinas , Polissacarídeos , Aminoácidos/química , Sítios de Ligação , Glicoproteínas de Hemaglutininação de Vírus da Influenza/química , Glicoproteínas de Hemaglutininação de Vírus da Influenza/metabolismo , Humanos , Lectinas/química , Lectinas/metabolismo , Polissacarídeos/química , Polissacarídeos/metabolismo , Ligação ProteicaRESUMO
In this manuscript the ability of selenium carbohydrates to undergo chalcogen bonding (ChB) interactions with protein residues has been studied at the RI-MP2/def2-TZVP level of theory. An inspection of the Protein Data Bank (PDB) revealed SeA (A = O, C and S) intermolecular contacts involving Se-pyranose ligands and ASP, TYR, SER and MET residues. Theoretical models were built to analyse the strength and directionality of the interaction together with "Atoms in Molecules" (AIM), Natural Bonding Orbital (NBO) and Non Covalent Interactions plot (NCIplot) analyses, which further assisted in the characterization of the ChBs described herein. We expect that the results from this study will be useful to expand the current knowledge regarding biological ChBs as well as to increase the visibility of the interaction among the carbohydrate chemistry community.
Assuntos
Lectinas/metabolismo , Monossacarídeos/metabolismo , Compostos Organosselênicos/metabolismo , Agaricales/química , Aspergillus oryzae/química , Bases de Dados de Proteínas , Escherichia coli/química , Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/metabolismo , Proteínas Fúngicas/química , Proteínas Fúngicas/metabolismo , Ligação de Hidrogênio , Lectinas/química , Modelos Moleculares , Monossacarídeos/química , Compostos Organosselênicos/química , Ligação Proteica , Selênio/química , Eletricidade Estática , TermodinâmicaRESUMO
BACKGROUND: Altered expression of N-glycans such as polylactosamine is observed in colon cancer. AHL, a polylactosamine specific lectin from Adenia hondala from a medicinal plant from the Passifloraceae family has been reported earlier. OBJECTIVE: The aim of the present study is to study the interaction of AHL with human colon cancer epithelial HT-29 cells and colon cancer tissues. METHODS: Cell viability was determined by MTT [3-[4, 5- dimethylthiazol-2-yl]-2, 5-diphenyltetrazolium bromide] assay, while cell surface binding, apoptosis by Annexin-V-PI assay and ROS production using DCFDA [2',7' - dichlorofluorescindiacetate] kit method were analysed by flowcytometry, immunohistochemistry was performed using biotinylated AHL, protein purification by affinity chromatography using asialofetuin-coupled Sepharose -4B column. RESULTS: AHL strongly binds to HT-29 cells with a Mean Fluorescence Intensity of 12.4, which could be blocked by competing glycoprotein asialofetuin. AHL inhibits HT-29 cell growth in a dose and time-dependent manner with IC50 of 2.5 µg/mL and differentially binds to human normal and cancerous tissues. AHL induces apoptosis and slight necrosis in HT-29 cells with an increase in the early apoptotic population of 25.1 and 36% for 24 h and 48 h respectively and necrotic population of 1.5 and 4.6% at 24 h and 48 h respectively as revealed by Annexin-V-PI assay. AHL induces the release of Reactive Oxygen Species in HT-29 cells in a dose-dependent manner. CONCLUSION: To the best of knowledge, this is the first report on lectin from Adenia hondala which is not a RIP with apoptotic and necrotic effects. These findings support the promising potential of AHL in cancer research.
Assuntos
Amino Açúcares/química , Neoplasias do Colo/tratamento farmacológico , Lectinas/química , Necrose/tratamento farmacológico , Passifloraceae/química , Extratos Vegetais/química , Polissacarídeos/química , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células HT29 , Humanos , Lectinas/farmacologia , Extratos Vegetais/farmacologia , Espécies Reativas de OxigênioRESUMO
Cancer notably carcinoma represents a prominent health challenge worldwide. A variety of chemotherapeutic agents are being used to deal with a variety of carcinomas. However, these delivering agents not only enter the targeted site but also affect normal tissues yielding poor therapeutic outcomes. Chemotherapeutic-associated problems are being attributed to drug non-specificity resulting from poor drug delivery systems. These problems are now being solved using nanomedicine, which entails using nanoparticles as drug delivery systems or nanocarriers. This nanoparticle-based drug delivery system enhances clinical outcomes by enabling targeted delivery, improving drug internalization, enhanced permeability, easy biodistribution, prolonged circulation and enhanced permeability rate, thereby improving the therapeutic effectiveness of several anticancer agents. Natural Protein-based Nanoparticles (PNPs) such as ferritin, lipoprotein, and lectins from natural sources have gained extensive importance at a scientific community level as nanovehicle for effective drug delivery and photo acoustic labeling replacing several synthetic nanocarriers that have shown limited therapeutic outcomes. The bioavailability of PNP, the chance of genetic engineering techniques to modify their biological properties made them one of the important raw material sources for drug delivery research. This current review highlighted different chemotherapeutic agents used in the treatment of some carcinomas. It also focused on the wide variety of natural protein sources derived nanoparticles (NPs) as anticancer delivery of agents for cancer therapy.
Assuntos
Antineoplásicos/uso terapêutico , Produtos Biológicos/química , Ferritinas/química , Lectinas/química , Lipoproteínas/química , Nanopartículas/química , Neoplasias/tratamento farmacológico , Antineoplásicos/química , Sistemas de Liberação de Medicamentos , HumanosRESUMO
Previous studies have characterized a saline extract from Microgramma vacciniifolia rhizome and its lectin (MvRL)-rich fraction with low acute toxicity. In the present study, we evaluated these preparations for acute toxicity (1,000â mg/kg) and antinociceptive and anti-inflammatory activities (100-400â mg/kg for the extract and 25-50â mg/kg for the fraction). No signs of toxicity were observed. Both the extract and fraction increased the latency period for nociception in the hot plate assay, decreased writhing induced by acetic acid, and promoted analgesic effects in phases 1 and 2 of the formalin test. The antinociceptive mechanism was attributed to interactions with opioid receptors and K+ ATPase channels. The extract and fraction decreased carrageenan-induced paw edema in 46.15 % and 77.22 %, respectively, at the highest doses evaluated. Furthermore, the fraction was shown to act on the bradykinin pathway. The ability to decrease leukocyte migration after treatment was also verified in the peritonitis and air pouch models. In exudates collected from air pouches, decreased tumor necrosis factor (TNF)-α and increased interleukin (IL)-10 levels were noted. Both the extract and fraction also effectively inhibited the development of granulomatous tissue. In conclusion, the substances investigated in this study can be used for the development of novel therapeutic options for pain and inflammatory processes.
Assuntos
Analgésicos/farmacologia , Anti-Inflamatórios/farmacologia , Edema/tratamento farmacológico , Lectinas/química , Extratos Vegetais/farmacologia , Rizoma/química , Analgésicos/química , Analgésicos/isolamento & purificação , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Carragenina , Movimento Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Edema/induzido quimicamente , Leucócitos/efeitos dos fármacos , Camundongos , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Receptores Opioides/metabolismo , Salinidade , ATPase Trocadora de Sódio-Potássio/antagonistas & inibidores , ATPase Trocadora de Sódio-Potássio/metabolismoRESUMO
Legumes are endowed with an opulent class of proteins called lectins that can detect tenuous variations in carbohydrate structures and bind them reversibly with high affinity and specificity. The genus Canavalia, in the family of Leguminosae, is considered to be an affluent source of lectin. An effort has been made to analyse the sequences encoded by the lectin gene and its carbohydrate binding pockets from three species of Canavalia, including C. virosa, C. rosea, and C. pubescens. Crude seed extract showed highest haemagglutination titer against buffalo RBCs and has high affinity to mannose and trehalose. Amplification of the lectin gene by gene-specific primers showed the presence of an 870 bp amplicon. Physicochemical characterization using various bioinformatic tools showed that the isoelectric point was below 7, suggesting that lectin molecules were acidic. A high aliphatic index and high instability index were observed, which indicated that lectin molecules were stable towards a wide range of temperatures. The occurrence of N-glycosylation sites at two sites was also identified in all three species. Prediction of secondary structure showed that approximately 59.05 %, 56.76 % and 54.88 % of the elements were random coils in the case of C. virosa, C. pubescens and C. rosea, respectively. Comparative modelling of the proteins and docking of hypothetical models with sugar moieties that inhibited the agglutination activity suggested that asparagine, serine, alanine, valine, tyrosine and threonine were the major residues involved in hydrogen bonding and other stacking interactions. This can further provide insights on its prospective antibiosis property.
Assuntos
Canavalia/genética , Carboidratos/química , Lectinas/química , Extratos Vegetais/química , Animais , Sítios de Ligação , Búfalos , Canavalia/classificação , Bovinos , Cabras , Lectinas/genética , Lectinas/isolamento & purificação , Extratos Vegetais/genética , Extratos Vegetais/isolamento & purificação , OvinosRESUMO
The red alga Kappaphycus striatus is economically important food species and extensively cultivated throughout most tropical parts of the world as a source of carrageenan. In this note, the primary structure of a new lectin KSL from this alga was elucidated by the rapid amplification method of complementary DNA (cDNA) ends, which consists of 267 amino acid residues distributed in four tandem-repeated domains of about 67 amino acids and sharing 43% of identity. The calculated molecular mass from the deduced sequence was consistent with that of natural KSL (27,826 Da) determined by electron spray ionization-mass spectrometry. The primary structure of KSL showed high similarity to those of the high mannose N-glycan specific lectins from marine red algae, ESA-2 from Eucheuma serra, EDA-2 from Eucheuma denticulatum, KSA-2 from Kappaphycus striatum, KAAs from Kappaphycus alvarezii and SfLs from Solieria filiformis, and from microorganisms, BOA from Burkholderia oklahomensis, MBHA from Myxococcus xanthus, OAA from Oscillatoria agardhii and PFL from Pseudomonas fluorescens. Furthermore, KSL showed anticancer effects against five carcinoma cell lines, HT29, Hela, MCF-7, SK-LU-1 and AGS, in a dose-dependent manner with the IC50 values of 0.80-1.94 µM, whereas its inhibition activities on cancer cells were not detected in the presence of yeast mannan, an inhibitor against lectin KSL. The cultivated red alga K. striatus could also be a good source of functional lectin(s) for application as anticancer agents.
Assuntos
Antineoplásicos/uso terapêutico , Lectinas/química , Rodófitas/química , Antineoplásicos/farmacologia , Humanos , Estrutura MolecularRESUMO
This work reports the effects of the water-soluble lectin from Moringa oleifera seeds (WSMoL) on growth and survival of Candida species. In addition, cellular alterations linked to the antifungal effect were investigated. The minimal inhibitory (MIC) and fungicidal (MFC) concentrations were determined and 24-h growth curves in absence and presence of lectin were established. Flow cytometry was used to evaluate the induction of apoptosis/necrosis, alterations in mitochondrial membrane potential (ΔΨm), and occurrence of lysosomal damage. WSMoL inhibited the growth of C. albicans, C. glabrata, C. krusei and C. parapsilosis with MIC of 20µg/mL. The lowest MFC (20µg/mL) was detected for C. glabrata and the highest (80µg/mL) for C. albicans and C. parapsilosis. The inhibitory effect started from the ninth to nineteenth hour of incubation depending on the fungal species. Incubation with the lectin at the MIC for 24h increased the number of cells undergoing apoptosis and necrosis. Hyperpolarization of the mitochondrial membrane was detected after 12-h treatment, followed by reduction of ΔΨm or depolarization after 24h. No lysosomal damage was detected in treated cells. In conclusion, WSMoL is a fungistatic and fungicide agent against Candida with differential effects depending on the species.
Assuntos
Antifúngicos/farmacologia , Candida/efeitos dos fármacos , Lectinas/farmacologia , Moringa oleifera/química , Extratos Vegetais/farmacologia , Sementes/química , Animais , Apoptose/efeitos dos fármacos , Candida/classificação , Candida/patogenicidade , Lectinas/química , Testes de Sensibilidade Microbiana , Necrose , Solubilidade , ÁguaRESUMO
The measures currently used to minimize the spread of arboviruses, comprising dengue, Chikungunya, and Zika virus, involve controlling the size of population of the mosquito Aedes aegypti. However, the search for formulations containing new insecticides is gaining pace due to reports of mosquito populations showing resistance to commonly used compounds. In this study, tablets containing a protein fraction of Moringa oleifera seeds enriched in the WSMoL lectin, known to show larvicidal and ovicidal activities against A. aegypti, were developed. The compatibility between the fraction and the excipients used in obtaining the tablets was evaluated by thermogravimetry (TG), differential scanning calorimetry (DSC), and Fourier transform infrared (FTIR) absorption spectroscopy. The larvicidal and ovicidal activities of the resulting tablets [5%, 10%, and 15% (w/w) of the fraction] were evaluated, as well as their effect on mosquito oviposition. Assays were also performed using a placebo tablet. According to the TG, DSC, and FTIR results, the protein composition of the fraction did not change when mixed with the components of the formulation. Tablets containing 10% and 15% WSMoL-rich fraction caused mortality of 42.5% and 95% of the larvae after 48 h, respectively, with larvae incubated with these tablets showing reduced acetylcholinesterase activity. All tablets inhibited egg hatching after 72 h (36-74%), and tablets containing 15% fraction were found to exert a repellent effect on oviposition. Our results show that the formulation developed in this study interfered with the life cycle of A. aegypti, and thus show potential for use in the control of this mosquito.
Assuntos
Aedes/efeitos dos fármacos , Inseticidas/farmacologia , Lectinas/farmacologia , Moringa oleifera/química , Extratos Vegetais/farmacologia , Sementes/química , Animais , Feminino , Inseticidas/química , Larva/efeitos dos fármacos , Lectinas/química , Oviposição/efeitos dos fármacos , Extratos Vegetais/químicaRESUMO
At present, specific therapies for COVID-19 are not well established, being certain only that the immune system plays a decisive role in the initiation and progression of the disease. Plants have given and continue to give compounds with great efficiency and low toxicity, some of them being a starting point for extremely effective synthetic substances. Although herbal remedies are used mainly for preventive purposes, there are also guidelines issued by some countries that indicate the use of traditional remedies for different stages of COVID-19 disease.Europe has a long and strong tradition of using medicinal plants for therapeutic purposes, but clinical trials for this type of approach are scarce, compared to Asia. In this regard, a bridge between tradition and science, would have a strong impact on the capacity for prevention and treatment of COVID-19. The paper reviews compounds of plant origin that have previously proven effective in counteracting some coronaviruses but also some of their major effects - direct action on virus replicative apparatus (viral entry or replication, action on the viral enzymatic system), collateral action of natural compounds on the immune system and also the contribution of herbal medicine as vaccine adjuvants are tackled.
Assuntos
Tratamento Farmacológico da COVID-19 , COVID-19/terapia , Extratos Vegetais/uso terapêutico , Preparações de Plantas/uso terapêutico , Plantas Medicinais/química , SARS-CoV-2/efeitos dos fármacos , Ensaios Clínicos como Assunto , Europa (Continente) , Humanos , Sistema Imunitário/efeitos dos fármacos , Lectinas/química , Óleos Voláteis/química , Fenóis/química , Fitoterapia , SARS-CoV-2/fisiologia , Saponinas/química , Internalização do Vírus/efeitos dos fármacos , Replicação Viral/efeitos dos fármacosRESUMO
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.
Assuntos
Lectinas/química , Lectinas/isolamento & purificação , Phaseolus/química , Extratos Vegetais/química , Eletroforese em Gel de Poliacrilamida , Hemaglutininas/química , Concentração de Íons de Hidrogênio , Fosfatos/química , Polietilenoglicóis/química , Proteínas/química , Sementes/química , Espectrofotometria , Propriedades de Superfície , TemperaturaRESUMO
Aedes aegypti control is a key component of the prophylaxis of dengue fever and other diseases. Moringa oleifera seeds contain a water-soluble lectin (WSMoL) with larvicidal and ovicidal activities against this insect. In this study, A. aegypti individuals were exposed at the third larval instar for 24â¯h to the water extract (0.1-1.0â¯mg/mL of protein) or lectin-rich fraction (0.05-0.6â¯mg/mL of protein) containing WSMoL, and then their survival and development were followed for 9 days post-exposure. The feeding capacity of adult females that developed from the treated larvae and the hatching success of eggs laid by them were also evaluated. Further, any alterations to the midgut histology of treated larvae, pupae, and adults were investigated. The extract and fraction induced the death of A. aegypti larvae along the post-exposure period. Both preparations also delayed the developmental cycle. The midguts of treated larvae and pupae showed disorganization and epithelial vacuolization, while in treated adults, the epithelium was underdeveloped compared to control. Unlike in control mosquitos, proliferating cells were not detected in treated larvae, and appeared in lower numbers in treated pupae than in control pupae. Adult females that developed from larvae treated with the fraction gained less weight after a blood meal compared with control. The amount of eggs laid by females that developed from larvae treated with both the extract and fraction was significantly lower than in control. In addition, the eggs showed lower hatching rates. In conclusion, females that developed from larvae treated with both the water extract and lectin-rich fraction showed reduced engorgement after a blood meal, with the consequent impairment of their fertility and fecundity. These results were probably due to the damage to midgut organization and impairment of the remodeling process during metamorphosis.
Assuntos
Aedes/efeitos dos fármacos , Lectinas/farmacologia , Moringa oleifera/química , Extratos Vegetais/farmacologia , Aedes/crescimento & desenvolvimento , Aedes/fisiologia , Animais , Feminino , Fertilidade/efeitos dos fármacos , Inseticidas/química , Inseticidas/farmacologia , Intestinos/efeitos dos fármacos , Intestinos/crescimento & desenvolvimento , Intestinos/patologia , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Larva/fisiologia , Lectinas/química , Controle de Mosquitos , Extratos Vegetais/química , Pupa/efeitos dos fármacos , Pupa/crescimento & desenvolvimento , Pupa/fisiologia , Sementes/química , Água/químicaRESUMO
In the present study, chitin specific lectin was purified from fruit exudates of Praecitrullus fistulosus. The lectin was purified and analyzed using affinity chromatography, RP-HPLC and electrophoretic studies. Furthermore, protein was identified by MALDI-MS/MS and peptide mass fingerprinting. Purified lectin (PfL) effectively agglutinates RBC, lymphocytes and displayed strong cytotoxicity against colon cancer (line HT29) cells among screened cells. PfL induced apoptosis by altering the expression of apoptotic proteins via caspadse-3 dependent pathway. In vivo studies using EAC mice model proves the efficacy of PfL by activating apoptosis and inhibiting the tumor neovasculature by targeting the MVD, VEGF and MMP's secretion. More importantly, the PfL treatment leads to effective inhibition of tumor growth and a â¼2.71 fold increase in the lifespan of EAC mice. Collectively, our study provides comprehensive evidence that the role of dietary lectins with significant cytotoxic potential by targeting tumor angiogenesis and activating apoptosis in cancer study models.