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1.
Molecules ; 25(18)2020 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-32899754

RESUMO

The emergence of the Coronavirus Disease 2019 (COVID-19) caused by the SARS-CoV-2 virus has led to an unprecedented pandemic, which demands urgent development of antiviral drugs and antibodies; as well as prophylactic approaches, namely vaccines. Algae biotechnology has much to offer in this scenario given the diversity of such organisms, which are a valuable source of antiviral and anti-inflammatory compounds that can also be used to produce vaccines and antibodies. Antivirals with possible activity against SARS-CoV-2 are summarized, based on previously reported activity against Coronaviruses or other enveloped or respiratory viruses. Moreover, the potential of algae-derived anti-inflammatory compounds to treat severe cases of COVID-19 is contemplated. The scenario of producing biopharmaceuticals in recombinant algae is presented and the cases of algae-made vaccines targeting viral diseases is highlighted as valuable references for the development of anti-SARS-CoV-2 vaccines. Successful cases in the production of functional antibodies are described. Perspectives on how specific algae species and genetic engineering techniques can be applied for the production of anti-viral compounds antibodies and vaccines against SARS-CoV-2 are provided.


Assuntos
Antivirais/farmacologia , Produtos Biológicos/farmacologia , Chlamydomonas reinhardtii/genética , Infecções por Coronavirus/tratamento farmacológico , Lectinas/farmacologia , Pneumonia Viral/tratamento farmacológico , Polifenóis/farmacologia , Polissacarídeos/farmacologia , Antivirais/química , Antivirais/isolamento & purificação , Betacoronavirus/efeitos dos fármacos , Betacoronavirus/patogenicidade , Produtos Biológicos/química , Produtos Biológicos/isolamento & purificação , Núcleo Celular/química , Núcleo Celular/genética , Núcleo Celular/metabolismo , Chlamydomonas reinhardtii/química , Chlamydomonas reinhardtii/metabolismo , Cloroplastos/química , Cloroplastos/genética , Cloroplastos/metabolismo , Infecções por Coronavirus/prevenção & controle , Engenharia Genética/métodos , Humanos , Lectinas/química , Lectinas/isolamento & purificação , Coronavírus da Síndrome Respiratória do Oriente Médio/efeitos dos fármacos , Coronavírus da Síndrome Respiratória do Oriente Médio/patogenicidade , Pandemias , Polifenóis/química , Polifenóis/isolamento & purificação , Polissacarídeos/química , Polissacarídeos/isolamento & purificação , Vírus da SARS/efeitos dos fármacos , Vírus da SARS/patogenicidade , Síndrome Respiratória Aguda Grave/tratamento farmacológico , Vacinas Virais/biossíntese , Vacinas Virais/farmacologia
2.
Toxicology ; 441: 152531, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32593706

RESUMO

Gene-regulatory networks reconstruction has become a very popular approach in applied biology to infer and dissect functional interactions of Transcription Factors (TFs) driving a defined phenotypic state, termed as Master Regulators (MRs). In the present work, cutting-edge bioinformatic methods were applied to re-analyze experimental data on leukemia cells (human myelogenous leukemia cell line THP-1 and acute myeloid leukemia MOLM-13 cells) treated for 6 h with two different Ribosome-Inactivating Proteins (RIPs), namely Shiga toxin type 1 (400 ng/mL) produced by Escherichia coli strains and the plant toxin stenodactylin (60 ng/mL), purified from the caudex of Adenia stenodactyla Harms. This analysis allowed us to identify the common early transcriptional response to 28S rRNA damage based on gene-regulatory network inference and Master Regulator Analysis (MRA). Both toxins induce a common response at 6 h which involves inflammatory mediators triggered by AP-1 family transcriptional factors and ATF3 in leukemia cells. We describe for the first time the involvement of MAFF, KLF2 and KLF6 in regulating RIP-induced apoptotic cell death, while receptor-mediated downstream signaling through ANXA1 and TLR4 is suggested for both toxins.


Assuntos
Redes Reguladoras de Genes/efeitos dos fármacos , Leucemia/metabolismo , Proteínas Inativadoras de Ribossomos/farmacologia , Linhagem Celular Tumoral , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Humanos , Lectinas/farmacologia , Proteínas de Membrana/efeitos dos fármacos , Proteínas de Membrana/metabolismo , N-Glicosil Hidrolases/farmacologia , Toxina Shiga I/farmacologia , Fatores de Transcrição/metabolismo
3.
Obes Facts ; 13(2): 221-236, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32252061

RESUMO

OBJECTIVES: To investigate the impact of omentin on the release of inflammation-related biomarkers and inflammatory pathways in primary human adipocytes. METHODS: Adipocytes were treated with or without omentin (500 and 2,000 ng/mL), and the supernatants were analyzed for inflammation-related biomarkers using proximity extension assay technology. Potential upstream regulators of the omentin-stimulated proteins were identified using Ingenuity Pathway Analysis. Protein levels of components of inflammatory pathways were measured using Western blotting. RESULTS: 2,000 ng/mL omentin induced the release of 30 biomarkers 97.1 ± 31.1-fold in the supernatants (all p < 0.05). Most biomarkers were proin-flammatory chemokines and cytokines. We identified the transcription factor nuclear factor "kappa-light-chain-enhancer" of activated B cells (NFĸB) and the kinases p38 and extracellular signal-regulated kinase (ERK)1/2 as potential upstream regulators in silico. On the cellular level, treatment with 2,000 ng/mL omentin for 24 h enhanced the phosphorylation levels of NFĸB 2.1 ± 0.3-fold (p < 0.05), of p38 2.6 ± 0.4-fold (p < 0.05), and of ERK1/2 1.8 ± 0.2-fold (p < 0.05). CONCLUSIONS: These data argue that omentin exerts proinflammatory effects through the activation of the inflammatory NFĸB, p38, and ERK1/2 pathways in cultured primary adipocytes.


Assuntos
Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Citocinas/farmacologia , Mediadores da Inflamação/metabolismo , Lectinas/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Adipócitos/citologia , Células Cultivadas , Citocinas/metabolismo , Relação Dose-Resposta a Droga , Proteínas Ligadas por GPI/farmacologia , Humanos , NF-kappa B/metabolismo , Cultura Primária de Células , Transdução de Sinais/efeitos dos fármacos , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
4.
PLoS One ; 15(3): e0230633, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32208440

RESUMO

Mast cells are connective tissue resident cells with morphological and functional characteristics that contribute to their role in allergic and inflammatory processes, host defense and maintenance of tissue homeostasis. Mast cell activation results in the release of pro-inflammatory mediators which are largely responsible for the physiological functions of mast cells. The lectin ArtinM, extracted from Artocarpus heterophyllus (jackfruit), binds to D-manose, thus inducing degranulation of mast cells. ArtinM has several immunomodulatory properties including acceleration of wound healing, and induction of cytokine release. The aim of the present study was to investigate the role of ArtinM in the activation and proliferation of mast cells. The rat mast cell line RBL-2H3 was used throughout this study. At a low concentration (0.25µg/mL), ArtinM induced mast cell activation and the release of IL-6 without stimulating the release of pre-formed or newly formed mediators. Additionally, when the cells were activated by ArtinM protein tyrosine phosphorylation was stimulated. The low concentration of ArtinM also activated the transcription factor NFkB, but not NFAT. ArtinM also affected the cell cycle and stimulated cell proliferation. Therefore, ArtinM may have therapeutic applications by modulating immune responses due to its ability to activate mast cells and promote the release of newly synthesized mediators. Additionally, ArtinM could have beneficial effects at low concentrations without degranulating mast cells and inducing allergic reactions.


Assuntos
Degranulação Celular/efeitos dos fármacos , Lectinas/farmacologia , Proteínas de Plantas/farmacologia , Animais , Artocarpus/metabolismo , Linhagem Celular , Membrana Celular/efeitos dos fármacos , Membrana Celular/ultraestrutura , Proliferação de Células/efeitos dos fármacos , Interleucina-6/metabolismo , Mastócitos/citologia , Mastócitos/metabolismo , Mitose/efeitos dos fármacos , NF-kappa B/metabolismo , Fosforilação/efeitos dos fármacos , Ratos
5.
Mol Immunol ; 121: 118-126, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32199211

RESUMO

Foot-and-mouth disease (FMD) is an acute, severe, and highly contagious disease that affects cloven-hoofed animals and can lead to serious economic losses and social effects. Therefore, a safe and effective subunit vaccine is required to prevent and control FMD. Dendritic cells (DCs) are a type of professional antigen presenting cell (APC). Immature DCs are typically stimulated by various adjuvants via immune receptors (e.g., toll-like receptor 4 [TLR4]), which activate DCs to induce their maturation. TLR4 has been well-established to induce both innate and adaptive immune responses to various external microbial or internal damage-related molecular patterns. In this study, the multi-epitope immunogen, HAO, of foot-and-mouth disease virus (FMDV) serotypes A and O was fused with the recombinant protein, heparin-binding hemagglutinin (HBHA), a novel TLR4 agonist, to obtain a new recombinant fusion protein, termed HAO-HBHA. HAO-HBHA was found to be highly efficient at activating murine DCs by the TLR4 pathway, both in vitro and in vivo. HAO-HBHA elicited strong specific humoral immune responses detected with an ELISA and virus neutralizing antibody test (VNT). HAO-HBHA also elevated the cellular immune responses, as indicated by intracellular cytokine (e.g., IFN-γ, TNF-α, IL-4, IL-6, IL-10, and IL-12p70) expression in Th1 and Th2 cells. As a TLR4 agonist, HBHA has significant advantages for enhancing the immune efficacy of a FMDV serotype A and O bivalent multi-epitope vaccine. These findings provide a novel strategy for the development of a safe and effective multi-epitope vaccine candidate against FMDV and further extends the application of TLR agonist-based vaccine platforms.


Assuntos
Vírus da Febre Aftosa/imunologia , Febre Aftosa/prevenção & controle , Lectinas/farmacologia , Vacinas Virais/administração & dosagem , Adjuvantes Imunológicos/farmacologia , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Células Dendríticas/imunologia , Epitopos de Linfócito B/genética , Epitopos de Linfócito B/imunologia , Epitopos de Linfócito T/genética , Epitopos de Linfócito T/imunologia , Feminino , Febre Aftosa/sangue , Febre Aftosa/imunologia , Febre Aftosa/virologia , Vírus da Febre Aftosa/genética , Imunidade Celular , Imunogenicidade da Vacina , Lectinas/imunologia , Camundongos , Mycobacterium tuberculosis/imunologia , Proteínas Recombinantes de Fusão/administração & dosagem , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/imunologia , Sorogrupo , Receptor 4 Toll-Like/agonistas , Receptor 4 Toll-Like/imunologia , Vacinas de Subunidades/administração & dosagem , Vacinas de Subunidades/genética , Vacinas de Subunidades/imunologia , Vacinas Virais/genética , Vacinas Virais/imunologia
6.
Insect Biochem Mol Biol ; 120: 103339, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32105779

RESUMO

Hemocytes, the immune cells in mosquitoes, participate in immune defenses against pathogens including malaria parasites. Mosquito hemocytes can also be infected by arthropod-borne viruses but the pro- or anti-viral nature of this interaction is unknown. Although there has been progress on hemocyte characterization during pathogen infection in mosquitoes, the specific contribution of hemocytes to immune responses and the hemocyte-specific functions of immune genes and pathways remain unresolved due to the lack of genetic tools to manipulate gene expression in these cells specifically. Here, we used the Gal4-UAS system to characterize the activity of the Drosophila hemocyte-specific hemolectin promoter in the adults of Anopheles gambiae, the malaria mosquito. We established an hml-Gal4 driver line that we further crossed to a fluorescent UAS responder line, and examined the expression pattern in the adult progeny driven by the hml promoter. We show that the hml regulatory region drives hemocyte-specific transgene expression in a subset of hemocytes, and that transgene expression is triggered after a blood meal. The hml promoter drives transgene expression in differentiating prohemocytes as well as in differentiated granulocytes. Analysis of different immune markers in hemocytes in which the hml promoter drives transgene expression revealed that this regulatory region could be used to study phagocytosis as well as melanization. Finally, the hml promoter drives transgene expression in hemocytes in which o'nyong-nyong virus replicates. Altogether, the Drosophila hml promoter constitutes a good tool to drive transgene expression in hemocyte only and to analyze the function of these cells and the genes they express during pathogen infection in Anopheles gambiae.


Assuntos
Anopheles/genética , Proteínas de Drosophila/farmacologia , Drosophila melanogaster/química , Expressão Gênica , Hemócitos/metabolismo , Lectinas/farmacologia , Animais , Anopheles/metabolismo , Linhagem Celular , Feminino
7.
Biochem Pharmacol ; 174: 113830, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32001235

RESUMO

High glucose-induced endothelial dysfunction is a critical initiating factor in the development of diabetic vascular complications. Omentin-1 has been regarded as a novel biomarker of endothelial function in subjects with type-2 diabetes (T2D); however, it is unclear whether omentin-1 has any direct effect in ameliorating high glucose-induced endothelial dysfunction. In the present study, we analyzed the effect of omentin-1 on high glucose-induced endothelial dysfunction in isolated mouse aortas and mouse aortic endothelial cells (MAECs). Vascular reactivity in aortas was measured using wire myography. The expression levels of AMP-activated protein kinase (AMPK), peroxisome proliferator-activated receptor δ (PPARδ), Akt, endothelial nitric-oxide synthase (eNOS), and endoplasmic reticulum (ER)-stress markers in MAECs were determined by Western blotting. The production of reactive oxygen species (ROS) and nitric oxide (NO) was assessed by diluted fluoroprobe, 2',7'-dichlorodihydrofluorescein diacetate (DCFH-DA) and 4-amino-5-methylamino-2',7'-difluorofluorescein (DAF-FM DA), respectively. We found that ex vivo treatment with omentin-1 reversed impaired endothelial-dependent relaxations (EDR) in mouse aortas after high-glucose insult. Elevated ER-stress markers, oxidative stress, and reduction of NO production induced by high glucose in MAECs were reversed by omentin-1 treatment. Omentin-1 also effectively reversed tunicamycin-induced ER stress responses in MAECs, as well as ameliorated impairment of endothelial-dependent relaxation in mouse aortas. Moreover, omentin-1 increased AMPK phosphorylation with a subsequent increase in PPARδ expression, while also restoring the decreased phosphorylation of Akt and eNOS. The effects of omentin-1 were abolished by cotreatment of compound C (AMPK inhibitor) and GSK0660 (PPARδ antagonist). These data indicate that omentin-1 protects against high glucose-induced vascular-endothelial dysfunction through inhibiting ER stress and oxidative stress and increasing NO production via activation of AMPK/PPARδ pathway.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Citocinas/farmacologia , Endotélio Vascular/metabolismo , Proteínas Ligadas por GPI/farmacologia , Glucose/toxicidade , Lectinas/farmacologia , PPAR delta/metabolismo , Transdução de Sinais/fisiologia , Animais , Células Cultivadas , Relação Dose-Resposta a Droga , Endotélio Vascular/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Técnicas de Cultura de Órgãos , Transdução de Sinais/efeitos dos fármacos
8.
Asian Pac J Cancer Prev ; 21(1): 99-106, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31983171

RESUMO

BACKGROUND: The effect of Aloctin, a lectin purified from Aloe vera leaves, and aloe emodin an anthraquinone glycoside purified from the leaves of the same plant, on several cancer cell lines was investigated. METHODS: Aloctin was isolated from A. vera leaf skin by ammonium sulphate precipitation and CNBr-Sepharose 4B-ovalbumin affinity chromatography. Specific new ligands for Aloctin were detected as fetuin and avidin by hemagglutination inhibition tests. The cytotoxic effect of Aloctin and aloe emodin on various human cancer cell lines was tested using MTT assay. Imatinib was tested as standard positive control. The mechanism underlying was tested by the Annexin V-FITC/PI test, with flow cytometry. RESULTS: The most sensitive cells to Aloctin and aloe emodin treatment, were identified as AGS human gastric adenocarcinoma cells. The effect was concentration dependent. It was shown that this effect does not occur by apoptosis or necrosis. In Aloctin-imatinib combinations studies, Aloctin significantly increased the cytotoxic effect of imatinib in a dose-dependent manner. It is expected that the results of this study will reveal important findings for the future use of A. vera lectin as well as aloe emodin in cancer research and contribution to lectin biochemistry.
.


Assuntos
Aloe/química , Antraquinonas/farmacologia , Antineoplásicos/farmacologia , Lectinas/farmacologia , Extratos Vegetais/farmacologia , Neoplasias Gástricas/tratamento farmacológico , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Folhas de Planta/química
9.
Arch Biochem Biophys ; 679: 108187, 2020 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-31706880

RESUMO

Macrophages play a pivotal role in the defense response against harmful pathogens and stimuli by releasing various pro-inflammatory mediators. However, overproduction of pro-inflammatory mediators will do harm to the organism and cause inflammation-associated diseases. Omentin-1, which is a newly discovered adipokine, is specifically expressed in omental adipose tissue. Recent studies have found correlations between omentin-1 and insulin resistance, diabetes, obesity, inflammation, atherosclerosis, bone metabolism, and tumor cell proliferation. Some studies have shown that the association between omentin-1, insulin resistance, and inflammation might suggest that omentin-1 plays an important role in chronic inflammatory diseases. In this study, we found that omentin-1 inhibited LPS-induced expression of inflammatory mediators and pro-inflammatory cytokines in macrophages. Furthermore, omentin-1 inhibited activation of the NF-κB pathway by suppressing both nuclear p65 accumulation and transfected NFκB promoter activity. Importantly, omentin-1 increased nuclear translocation of Nrf2. Our findings demonstrate that omentin-1 exerts anti-inflammatory effects on LPS-induced macrophages and has potential implication in the treatment of inflammation-associated diseases.


Assuntos
Lectinas/farmacologia , Lipopolissacarídeos/farmacologia , Ativação de Macrófagos/efeitos dos fármacos , Fator 88 de Diferenciação Mieloide/metabolismo , NF-kappa B/metabolismo , Transdução de Sinais/efeitos dos fármacos , Receptor 4 Toll-Like/metabolismo , Ciclo-Oxigenase 2/metabolismo , Citocinas/metabolismo , Dinoprostona/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Fator 2 Relacionado a NF-E2/metabolismo , Óxido Nítrico/biossíntese , Óxido Nítrico Sintase Tipo II/metabolismo , Células U937
10.
Arch Insect Biochem Physiol ; 103(1): e21623, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31579962

RESUMO

Cytolytic activity against invading microorganisms is one of the innate forms of immunity in invertebrates. A serine protease-associated sialic acid-specific cytolytic lectin was purified using glutaraldehyde-fixed ox erythrocytes from the larval extract of blowfly (Chrysomya megacephala). The purified lectin lysed vertebrate erythrocytes with effective haemolysis of ox red blood cells (RBCs) in an isotonic medium. The degree of haemolytic (HL) activity of the purified cytolytic lectin depended on its concentration, pH, temperature, and calcium ions. It was sensitive to ethylenediaminetetraacetic acid. The native molecular mass of the C-type lectin was 260 ± 26 kDa, comprising four different polypeptide subunits of 75 kDa (pI ~8), 69 kDa (pI ~7.0), 61 kDa (pI ~5.3), and 55 kDa (pI ~4.6). The association between the C-type lectin and serine protease was confirmed by MALDI-TOF-MS analysis that revealed its homology in the same spectral peak as well as the proteases and phenylmethylsulphonyl fluoride inhibition of HL activity. Haemolysis inhibition by N-acetylneuraminic acid and other sugars revealed the properties of the lectin. The purified lectin distorted the integrity of ox RBCs and Paenalcaligenes hermetiae. This in vitro study documents the presence of a cytolytic system in blowfly (C. megacephala) larvae for the clearance of invading microbial pathogens in their feeding niche.


Assuntos
Lectinas/química , Alcaligenaceae/efeitos dos fármacos , Animais , Bovinos , Dípteros/química , Hemólise , Proteínas de Insetos/química , Larva/química , Lectinas/farmacologia , Lectinas Tipo C/química , Serina Proteases/química
11.
Mar Drugs ; 18(1)2019 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-31877692

RESUMO

Often, even the most effective antineoplastic drugs currently used in clinic do not efficiently allow complete healing due to the related toxicity. The reason for the toxicity lies in the lack of selectivity for cancer cells of the vast majority of anticancer agents. Thus, the need for new potent anticancer compounds characterized by a better toxicological profile is compelling. Lectins belong to a particular class of non-immunogenic glycoproteins and have the characteristics to selectively bind specific sugar sequences on the surface of cells. This property is exploited to exclusively bind cancer cells and exert antitumor activity through the induction of different forms of regulated cell death and the inhibition of cancer cell proliferation. Thanks to the extraordinary biodiversity, marine environments represent a unique source of active natural compounds with anticancer potential. Several marine and freshwater organisms, ranging from the simplest alga to the most complex vertebrate, are amazingly enriched in these proteins. Remarkably, all studies gathered in this review show the impressive anticancer effect of each studied marine lectin combined with irrelevant toxicity in vitro and in vivo and pave the way to design clinical trials to assess the real antineoplastic potential of these promising proteins. It provides a concise and precise description of the experimental results, their interpretation as well as the experimental conclusions that can be drawn.


Assuntos
Antineoplásicos/farmacologia , Organismos Aquáticos , Lectinas/farmacologia , Neoplasias/tratamento farmacológico , Sequência de Aminoácidos , Animais , Produtos Biológicos/farmacologia , Água Doce , Humanos , Lectinas/química
12.
J Basic Microbiol ; 59(12): 1238-1247, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31613018

RESUMO

Penicillium griseoroseum lectin was 80-fold purified by successive DEAE Sepharose anion exchange and Sephadex G-100 gel permeation chromatography. P. griseoroseum lectin exhibited haemagglutination activity towards protease-treated rabbit erythrocytes. It showed specificity towards various carbohydrates such as d-mannose, N-acetyl-d-glucosamine, mucins, and so forth. P. griseoroseum lectin was found as a glycoprotein with glycan content of 4.33%. Purified P. griseoroseum lectin is homodimeric having a molecular mass of 57 kDa with subunit molecular mass of 28.6 kDa. Haemagglutination activity of purified P. griseoroseum lectin was completely stable from 25°C to 35°C at a pH range of 6-7.5. Lectin activity was not influenced by divalent metal ions and denaturants. P. griseoroseum lectin manifested mitogenicity towards mice splenocytes and activity reached a peak at 75 µg/ml of lectin concentration. P. griseoroseum lectin in microgram concentrations stimulated proliferation of mice splenocytes. Thus, P. griseoroseum lectin exhibits potential mitogenicity, which can be exploited for further biomedical applications.


Assuntos
Lectinas/química , Lectinas/isolamento & purificação , Mitógenos/química , Mitógenos/isolamento & purificação , Penicillium/química , Animais , Carboidratos/química , Cátions/metabolismo , Proliferação de Células/efeitos dos fármacos , Quelantes , Glicoproteínas/química , Hemaglutinação , Concentração de Íons de Hidrogênio , Lectinas/farmacologia , Masculino , Camundongos , Mitógenos/farmacologia , Peso Molecular , Multimerização Proteica , Estabilidade Proteica , Temperatura
13.
Fish Shellfish Immunol ; 94: 896-906, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31533083

RESUMO

The study is carried out to understand the antimicrobial and immunological response of a potential immune molecule lectin, MmLec isolated from haemolymph of Speckled shrimp, Metapenaeus monoceros. MmLec was purified using mannose coupled Sepharose CL-4B affinity chromatography, which was further subjected on SDS-PAGE to ascertain the distribution of their molecular weight. Sugar binding specificity assay was conducted at various pH and temperatures to investigate the binding affinity of MmLec towards the specific carbohydrate molecule. Functional analysis of immune molecule MmLec included haemagglutination assays performed using human erythrocytes and yeast agglutination activity against Saccharomyces cerevisiae which, were analyzed using light microscopy. In order to study the antimicrobial activity, two Gram-negative (Vibrio parahaemolyticus and Aeromonas hydrophila) and two Gram-positive (Staphylococcus aureus and Enterococcus faecalis) bacteria were treated with purified MmLec. Moreover, these bacterial species were also treated at different concentration of the MmLec to speculate the antibiofilm properties of MmLec which was analyzed under Light Microscopy and Confocal Laser Scanning Microscopy. In addition, other functional characterization of MmLec showed the uniqueness of MmLec in agglutination of human erythrocyte as well as the cells of yeast Saccharomyces cerevisiae. Also, the phenoloxidase activity and encapsulation assay was evaluated. MTT assay displayed that MmLec are potent in anticancer activity. The study will help to understand the immunological interference and antimicrobial nature of MmLec which would be supportive in establishing a potential therapeutic tool and to develop better and novel disease control strategies in shrimp and farmed aquaculture industries as well as in health management.


Assuntos
Biofilmes/efeitos dos fármacos , Lectinas/imunologia , Penaeidae/imunologia , Aeromonas hydrophila/fisiologia , Animais , Enterococcus faecalis/fisiologia , Hemolinfa/química , Lectinas/farmacologia , Penaeidae/fisiologia , Staphylococcus aureus/fisiologia , Vibrio parahaemolyticus/fisiologia
14.
Int J Biol Macromol ; 140: 234-244, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31400430

RESUMO

Carbohydrate-binding proteins, also known as lectins, are valuable tools for biotechnology, including pharmacological uses. Mannose lectins obtained from plant and animal sources are applied to protection and characterization of autoimmune diseases as well as defense proteins against pathogens. The presence of mannose-binding lectins in plants that also recognize glucose could be entitled Man/Glc lectins; such specificity has allowed employing these vegetal lectins for several applications. Animal mannose-binding lectins are synthesized in the liver and secreted into the blood stream where both concentration and activity are greatly affected due to gene polymorphisms; these serum proteins play important roles in the immune system by recognizing mannose-like carbohydrate ligands found exclusively on pathogenic microorganisms. Mannose lectins already showed strong binding to relevant bacteria, viruses, protozoa and helminth species, initiating potent host defense mechanisms by inducing growth inhibition or death of such organisms; the ability to prevent the formation or destruction of microbial biofilms has also been reported. Mannose-binding lectins have attracted considerable attention against carcinogenesis and atherogenesis. The aim of this review article is to approach biotechnology characteristics of these lectins from different sources and microorganism/cell surface interactions with mannose; in addition, aspects of mechanisms associated to lectin antipathogenic activities are described.


Assuntos
Anti-Infecciosos/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Lectinas/farmacologia , Lectinas de Ligação a Manose/farmacologia , Plantas/química , Animais , Anti-Infecciosos/química , Antineoplásicos Fitogênicos/química , Sítios de Ligação , Biotecnologia , Proliferação de Células/efeitos dos fármacos , Glicosilação , Lectinas/química , Manose/química , Manose/metabolismo , Lectinas de Ligação a Manose/química , Modelos Moleculares , Lectinas de Plantas/farmacologia , Ligação Proteica
15.
Mar Drugs ; 17(9)2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31466257

RESUMO

MytiLec-1, a 17 kDa lectin with ß-trefoil folding that was isolated from the Mediterranean mussel (Mytilus galloprovincialis) bound to the disaccharide melibiose, Galα(1,6) Glc, and the trisaccharide globotriose, Galα(1,4) Galß(1,4) Glc. Toxicity of the lectin was found to be low with an LC50 value of 384.53 µg/mL, determined using the Artemia nauplii lethality assay. A fluorescence assay was carried out to evaluate the glycan-dependent binding of MytiLec-1 to Artemia nauplii. The lectin strongly agglutinated Ehrlich ascites carcinoma (EAC) cells cultured in vivo in Swiss albino mice. When injected intraperitoneally to the mice at doses of 1.0 mg/kg/day and 2.0 mg/kg/day for five consecutive days, MytiLec-1 inhibited 27.62% and 48.57% of cancer cell growth, respectively. Antiproliferative activity of the lectin against U937 and HeLa cells was studied by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay in vitro in RPMI-1640 medium. MytiLec-1 internalized into U937 cells and 50 µg/mL of the lectin inhibited their growth of to 62.70% whereas 53.59% cell growth inhibition was observed against EAC cells when incubated for 24 h. Cell morphological study and expression of apoptosis-related genes (p53, Bax, Bcl-X, and NF-κB) showed that the lectin possibly triggered apoptosis in these cells.


Assuntos
Produtos Biológicos/farmacologia , Carcinoma de Ehrlich/tratamento farmacológico , Dissacarídeos/farmacologia , Lectinas/farmacologia , Mytilus/química , Trissacarídeos/farmacologia , Animais , Apoptose/efeitos dos fármacos , Artemia/efeitos dos fármacos , Produtos Biológicos/química , Produtos Biológicos/uso terapêutico , Carcinoma de Ehrlich/patologia , Proliferação de Células/efeitos dos fármacos , Dissacarídeos/química , Dissacarídeos/uso terapêutico , Ensaios de Seleção de Medicamentos Antitumorais , Células HeLa , Humanos , Injeções Intraperitoneais , Lectinas/química , Lectinas/uso terapêutico , Melibiose/química , Camundongos , Testes de Toxicidade , Trissacarídeos/química , Trissacarídeos/uso terapêutico , Células U937
16.
Ecotoxicol Environ Saf ; 183: 109583, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31446169

RESUMO

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 24 h to the water extract (0.1-1.0 mg/mL of protein) or lectin-rich fraction (0.05-0.6 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/química
17.
Curr Pharm Biotechnol ; 20(15): 1236-1243, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31333121

RESUMO

BACKGROUND: The immune system is responsible for providing protection to the body against foreign substances. The immune system divides into two types of immune responses to study its mechanisms of protection: 1) Innate and 2) Adaptive. The innate immune response represents the first protective barrier of the organism that also works as a regulator of the adaptive immune response, if evaded the mechanisms of the innate immune response by the foreign substance the adaptive immune response takes action with the consequent antigen neutralization or elimination. The adaptive immune response objective is developing a specific humoral response that consists in the production of soluble proteins known as antibodies capable of specifically recognizing the foreign agent; such protective mechanism is induced artificially through an immunization or vaccination. Unfortunately, the immunogenicity of the antigens is an intrinsic characteristic of the same antigen dependent on several factors. CONCLUSION: Vaccine adjuvants are chemical substances of very varied structure that seek to improve the immunogenicity of antigens. The main four types of adjuvants under investigation are the following: 1) Oil emulsions with an antigen in solution, 2) Pattern recognition receptors activating molecules, 3) Inflammatory stimulatory molecules or activators of the inflammasome complex, and 4) Cytokines. However, this paper addresses the biological plausibility of two phytochemical compounds as vaccine adjuvants: 5) Lectins, and 6) Plant phenolics whose characteristics, mechanisms of action and disadvantages are addressed. Finally, the immunological usefulness of these molecules is discussed through immunological data to estimate effects of plant phenolics and lectins as vaccine adjuvants, and current studies that have implanted these molecules as vaccine adjuvants, demonstrating the results of this immunization.


Assuntos
Adjuvantes Imunológicos/farmacologia , Lectinas/farmacologia , Plantas/química , Polifenóis/farmacologia , Imunidade Adaptativa/efeitos dos fármacos , Adjuvantes Imunológicos/isolamento & purificação , Animais , Antígenos/imunologia , Citocinas/imunologia , Humanos , Imunidade Inata/efeitos dos fármacos , Lectinas/imunologia , Lectinas/isolamento & purificação , Polifenóis/imunologia , Polifenóis/isolamento & purificação , Vacinação/métodos , Vacinas/imunologia
18.
PLoS One ; 14(7): e0220318, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31344098

RESUMO

Lectins are a group of ubiquitous proteins which specifically recognize and reversibly bind sugar moieties of glycoprotein and glycolipid constituents on cell surfaces. The mutagenesis approach is often employed to characterize lectin binding properties. As lectins are not enzymes, it is not easy to perform a rapid specificity screening of mutants using chromogenic substrates. It is necessary to use different binding assays such as isothermal titration calorimetry (ITC), surface plasmon resonance (SPR), microscale thermophoresis (MST), enzyme-linked lectin assays (ELLA), or glycan arrays for their characterization. These methods often require fluorescently labeled proteins (MST), highly purified proteins (SPR) or high protein concentrations (ITC). Mutant proteins may often exhibit problematic behaviour, such as poor solubility or low stability. Lectin-based cell agglutination is a simple and low-cost technique which can overcome most of these problems. In this work, a modified method of the agglutination of human erythrocytes and yeast cells with microscopy detection was successfully used for a specificity study of the newly prepared mutant lectin RS-IIL_A22S, which experimentally completed studies on sugar preferences of lectins in the PA-IIL family. Results showed that the sensitivity of this method is comparable with ITC, is able to determine subtle differences in lectin specificity, and works directly in cell lysates. The agglutination method with microscopy detection was validated by comparison of the results with results obtained by agglutination assay in standard 96-well microtiter plate format. In contrast to this assay, the microscopic method can clearly distinguish between hemagglutination and hemolysis. Therefore, this method is suitable for examination of lectins with known hemolytic activity as well as mutant or uncharacterized lectins, which could damage red blood cells. This is due to the experimental arrangement, which includes very short sample incubation time in combination with microscopic detection of agglutinates, that are easily observed by a small portable microscope.


Assuntos
Testes de Aglutinação , Proteínas de Bactérias/farmacologia , Eritrócitos/efeitos dos fármacos , Lectinas/farmacologia , Leveduras/efeitos dos fármacos , Aglutinação/efeitos dos fármacos , Testes de Aglutinação/métodos , Eritrócitos/citologia , Proteínas de Escherichia coli/farmacologia , Hemaglutinação/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Humanos , Microscopia , Saccharomyces cerevisiae/citologia , Saccharomyces cerevisiae/efeitos dos fármacos , Ressonância de Plasmônio de Superfície , Leveduras/citologia
19.
Microb Pathog ; 135: 103629, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31325571

RESUMO

Lectins have been studied in the past few years as an alternative to inhibit the development of pathogenic bacteria and gastrointestinal nematodes of small ruminants. The development of new antibacterial and anthelmintic compounds is necessary owing to the increase in drug resistance among important pathogens. Therefore, this study aimed to evaluate the capacity of a glucose/mannose-binding lectin from Parkia platycephala seeds (PPL) to inhibit the development of Haemonchus contortus and to modulate antibiotic activity against multi-resistant bacterial strains, thereby confirming its efficacy when used in combination with gentamicin. PPL at the concentration of 1.2 mg/mL did not show inhibitory activity on H. contortus in the egg hatch test or the exsheathment assay. However, it did show significant inhibition of H. contortus larval development with an IC50 of 0.31 mg/mL. The minimum inhibitory concentration (MIC) obtained for PPL against all tested bacterial strains was not clinically relevant (MIC ≥ 1024 µg/mL). However, when PPL was combined with gentamicin, a significant increase in antibiotic activity was observed against S. aureus and E.coli multi-resistant strains. The inhibition of hemagglutinating activity by gentamicin (MIC = 50 mM) revealed that it may be interacting with the carbohydrate-binding site of PPL. It is this interaction between the antibiotic and lectin carbohydrate-binding site that may be responsible for the enhanced activity of gentamicin against multi-resistant strains. It can be concluded that PPL showed selective anthelmintic effect, inhibiting the development of H. contortus larvae and that it increased the effect of the antibiotic gentamicin against multi-resistant bacterial strains, thus constituting a potential therapeutic resource against resistant bacterial strains and H. contortus.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Fabaceae/química , Haemonchus/efeitos dos fármacos , Haemonchus/crescimento & desenvolvimento , Lectinas/farmacologia , Extratos Vegetais/farmacologia , Animais , Anti-Helmínticos/farmacologia , Gentamicinas/farmacologia , Haemonchus/microbiologia , Larva/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Sementes/química , Staphylococcus aureus/efeitos dos fármacos
20.
Int J Biol Macromol ; 138: 890-902, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31344413

RESUMO

The present work aimed to evaluate the antioxidant efficacy of beta-1,3-glucan binding/recognition protein against oxidative stress-induced Saccharomyces cerevisiae. Beta-1,3-glucan binding/recognition protein was attained from the Paratelphusa hydrodromus (Phß-GBP) using laminarin coupled Sepharose CL-6B column. The structural characteristics of Phß-GBP were analyzed through circular dichroism (CD), fourier transform infrared spectroscopy (FTIR) and proton nuclear magnetic resonance spectroscopy (1H NMR) analysis. CD spectrum showed the occurrence of α-helix (4.5%), ß-sheets (23.6%), ß-turn (17.2%) and random coils (54.8%). FTIR confirms the occurrence of amide and aromatic compounds whereas 1H NMR predicts the secondary structures and presence of amino acids in the Phß-GBP. In vitro radical scavenging analysis disclose that Phß-GBP has the potential to scavenge DPPH (73%), peroxyl radicals (81%) and hydrogen peroxide (56%) at 100µg/ml concentration. Reactive oxygen species production, lipid peroxidation, cell death, and DNA damage were decreased in the Phß-GBP pretreated S. cerevisiae. In silico protein-protein interaction was performed between the ß-GBP-glutathione reductase and ß-GBP-catalase A. The interaction study reveals that glutathione reductase and catalase A interacts with ß-GBP to reduce the oxidized glutathione and remove free radicals. This finding demonstrates that Phß-GBP may act as a good antioxidant which protects from human pathologies linked with oxidative stress.


Assuntos
Amidinas/farmacologia , Antioxidantes/farmacologia , Proteínas de Transporte/farmacologia , Lectinas/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/metabolismo , Amidinas/química , Antioxidantes/química , Proteínas de Transporte/química , Dano ao DNA/efeitos dos fármacos , Depuradores de Radicais Livres/farmacologia , Lectinas/química , Peroxidação de Lipídeos/efeitos dos fármacos , Modelos Moleculares , Conformação Molecular , Mapeamento de Interação de Proteínas , Espécies Reativas de Oxigênio/metabolismo , Proteínas Recombinantes/farmacologia , Proteínas de Saccharomyces cerevisiae/metabolismo , Análise Espectral , Relação Estrutura-Atividade
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