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1.
J Ethnopharmacol ; 268: 113607, 2021 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-33242625

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Since drugs currently used to manage pain and inflammatory conditions present several side effects, the investigation of new anti-inflammatory and antinociceptive agents from folk-medicine plants is an important approach. Costus spiralis (Costaceae) has been used in Brazilian medicinal teas to treat urinary infection, cough, inflammation, arthritis, among others. AIM OF THE STUDY: The current study focused on investigating anti-inflammatory and antinociceptive effects of fractions from C. spiralis leaves using animal models. MATERIALS AND METHODS: Adults Swiss mice were used in the following experimental models: acetic acid-induced abdominal writhing, formalin-induced nociception, hot plate, zymosan-induced peritonitis, and arthritis induced by complete Freund's adjuvant. RESULTS: The presence of steroids was confirmed in all fractions. Flavonoids, condensed tannins and saponins were observed in EFL. In methanolic fraction leaves (MFL), the presence of flavonoids and pentacyclic triterpenoids was confirmed. Orally administered leaf fractions significantly reduced abdominal writhing. Fractions were ineffective in the neurogenic stage of the formalin test, but in the inflammatory stage, ethyl acetate fraction levaes (AcFL), ethanolic fraction leaves (EFL), and MFL significantly reduced paw licking time by 69.6 ± 11.9%, 58.2 ± 9.4%, and 79.6 ± 8.3%, respectively. In the hot plate test, the reaction latency was similar for treated animals and controls. However, in the peritonitis test, cell migration was significantly reduced in animals treated with chloroform fractions leaves ClFL (61.8 ± 11.4%), AcFL (58.7 ± 8.3%), EFL (39.2 ± 5.0%), and MFL (64.8 ± 4.4%). This was similar to the result observed in the chronic inflammation model, this time only the chloroform fraction was able to reduce paw edema. CONCLUSION: Our results show that leaf fractions of Costus spiralis are capable of modulating peripheral nociceptive and inflammatory responses without effects on central nervous system being potential substrates for phytochemical purification, structural and mechanistic studies.


Assuntos
Analgésicos/uso terapêutico , Anti-Inflamatórios/uso terapêutico , Artrite Experimental/tratamento farmacológico , Costus , Medição da Dor/efeitos dos fármacos , Extratos Vegetais/uso terapêutico , Analgésicos/isolamento & purificação , Analgésicos/farmacologia , Animais , Anti-Inflamatórios/isolamento & purificação , Anti-Inflamatórios/farmacologia , Artrite Experimental/induzido quimicamente , Artrite Experimental/metabolismo , Feminino , Masculino , Camundongos , Medição da Dor/métodos , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Folhas de Planta
2.
Asian Pac J Cancer Prev ; 21(1): 25-29, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31983159

RESUMO

OBJECTIVE: Perform genotyping of SNPs in the promoter region of the SMO gene in BCC samples from patients from northeastern Brazil, and to determine if there is an association of these SNPs of the gene in question with the susceptibility to the development of the BCC. METHODS: 100 samples of paraffined tissue from patients with histopathological diagnosis of BCC and 100 control samples were analyzed for each polymorphism by a newly developed genotyping method, the Dideoxy Single Allele Specific - PCR. The software Bioestat - version 5.3 and Haploview 4.2 were used for the statistical analysis. For all tests a P-value.


Assuntos
Carcinoma Basocelular/genética , Ilhas de CpG/genética , Metilação de DNA/genética , Polimorfismo de Nucleotídeo Único/genética , Regiões Promotoras Genéticas/genética , Neoplasias Cutâneas/genética , Receptor Smoothened/genética , Alelos , Biomarcadores Tumorais/genética , Brasil , Predisposição Genética para Doença/genética , Humanos , Estudos Retrospectivos
3.
Arch Biochem Biophys ; 664: 149-156, 2019 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-30772259

RESUMO

A new mannose/N-acetyl-dglucosamine-specific lectin, named MaL, was purified from seeds of Machaerium acutifolium by precipitation with ammonium sulfate, followed by affinity and ion-exchange chromatography. MaL haemagglutinates either native rabbit erythrocytes or those treated with proteolytic enzymes. MaL is highly stable by the ability to maintain its haemagglutinating activity after exposure to temperatures up to 50 °C. The lectin haemagglutinating activity was optimum between pH 6.0 and 7.0 and inhibited after incubation with d-mannose and N-acetyl-d-glucosamine and α-methyl-d-mannopyranoside. MaL is a glycoprotein with relative molecular mass of 29 kDa (α-chain), 13 kDa (ß-chain) and 8 kDa (γ-chain) with secondary structure composed of 3% α-helix, 44% ß-sheet, 21% ß-turn, and 32% coil. The orofacial antinociceptive activity of the lectin was also evaluated. MaL (0.03 mg mL-1) reduced orofacial nociception induced by capsaicin, an effect that occurred via carbohydrate recognition domain interaction, suggesting an interaction of MaL with the transient receptor potential cation channel subfamily V member 1 (TRPV1) receptor. Our results confirm the potential pharmacological relevance of MaL as an inhibitor of acute orofacial mediated by TRPV1.


Assuntos
Acetilglucosamina/química , Fabaceae/química , Dor Facial/tratamento farmacológico , Lectinas/isolamento & purificação , Lectinas/uso terapêutico , Manose/química , Canais de Cátion TRPV/metabolismo , Sequência de Aminoácidos , Animais , Fenômenos Biofísicos , Cromatografia de Afinidade , Eletroforese em Gel de Poliacrilamida , Feminino , Lectinas/química , Masculino , Estrutura Secundária de Proteína , Coelhos , Espectrometria de Massas em Tandem , Peixe-Zebra
4.
Mol Biochem Parasitol ; 225: 67-72, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30217772

RESUMO

Haemonchus contortus is one of the most economically important parasites infecting small ruminants worldwide. This nematode has shown a great ability to develop resistance to anthelmintic drugs, calling for the development of alternative control approaches. Because lectins recognize and bind to specific carbohydrates and glycan structures present in parasites, they can be considered as an alternative to develop new antiparasitic drugs. Accordingly, this work aimed to investigate the anthelmintic effect of Canavalia brasiliensis (ConBr) lectin against H. contortus and to evaluate a possible interaction of ConBr with glycans of this parasite by molecular docking. ConBr showed significant inhibition of H. contortus larval development with an IC50 of 0.26 mg mL-1. Molecular docking assays revealed that glycans containing the core trimannoside [Man(α1-3)Man(α1-6)Man] of H. contortus interact in the carbohydrate recognition domain of ConBr with an interaction value of MDS = -248.77. Our findings suggest that the inhibition of H. contortus larval development is directly related to the recognition of the core trimannoside present in the glycans of these parasites. This work is the first to report on the structure-function relationships of the anthelmintic activity of plant lectins.


Assuntos
Anti-Helmínticos/química , Anti-Helmínticos/metabolismo , Haemonchus/efeitos dos fármacos , Manosídeos/metabolismo , Lectinas de Plantas/química , Lectinas de Plantas/metabolismo , Animais , Anti-Helmínticos/isolamento & purificação , Sítios de Ligação , Canavalia/química , Haemonchus/crescimento & desenvolvimento , Concentração Inibidora 50 , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Simulação de Acoplamento Molecular , Lectinas de Plantas/isolamento & purificação , Ligação Proteica
6.
Pathol Oncol Res ; 24(3): 489-496, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28667494

RESUMO

Basal cell carcinoma - BCC is considered a multifactorial neoplasm involving genetic, epigenetic and environmental factors. Where UVB radiation is considered the main physical agent involved in BCC carcinogenesis. The Brazil and state of Paraíba are exposed to high levels of UVB rays. The mismatch repair - MMR is important DNA repair mechanisms to maintain replication fidelity. Therefore, single nucleotide polymorphisms (SNPs) in genes encoding proteins involved in MMR may be potential molecular markers of susceptibility to BCC. The objective of this study was to evaluate and describe for the first time the SNPs rs560246973, rs2303425 and rs565410865 and risk of developing BCC. The present study analyzed 100 samples of paraffin-embedded tissue from patients with histopathological diagnosis of BCC and 100 control samples. The results were obtained by genotyping method, Dideoxy Unique Allele Specific - PCR (DSASP). The SNPs rs2303425 were not associated with Basal Cell Carcinoma. However, the SNPs rs560246973 and rs565410865 was shown to be associated with the development of BCC when compared to control samples (P < 0.0001). The SNPs rs565410865 was also statistical significance between the genotypes of and the age group (p = 0.0027) and tumor location (p = 0,0191). The result suggests that SNPs rs2303425 and rs565410865 are associated with susceptibility to the development of BCC in the Brazilian population and may be considered as potential molecular markers for BCC.


Assuntos
Biomarcadores Tumorais/genética , Carcinoma Basocelular/genética , Proteína 1 Homóloga a MutL/genética , Proteína 2 Homóloga a MutS/genética , Polimorfismo de Nucleotídeo Único , Neoplasias Cutâneas/genética , Brasil/epidemiologia , Carcinoma Basocelular/epidemiologia , Carcinoma Basocelular/patologia , Estudos de Casos e Controles , Predisposição Genética para Doença , Humanos , Prognóstico , Estudos Retrospectivos , Neoplasias Cutâneas/epidemiologia , Neoplasias Cutâneas/patologia
7.
Front Physiol ; 8: 196, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28408889

RESUMO

Nutritional intervention with antioxidants rich foods has been considered a strategy to minimize the effects of overtraining in athletes. This experimental, randomized, and placebo-controlled study evaluated the effects of consumption of sesame (Sesamum indicum L.) on muscle damage markers, oxidative stress, systemic inflammation, and aerobic performance in male semi-professional soccer players. Twenty athletes were randomly assigned to groups that received 40 g (two tablespoons) per day of sesame or a placebo during 28 days of regular training (exposed to routine training that includes loads of heavy training in the final half of the season). Before and after intervention, creatine kinase (CK), lactate dehydrogenase (LDH), malondialdehyde (MDA), superoxide dismutase (SOD), C-reactive protein (hs-CRP), and aerobic capacity were evaluated. Before intervention, a physiologic imbalance was noted in both groups related to CK and LDH levels. Sesame intake caused a reduction of CK (19%, p < 0.05), LDH (37%, p < 0.05), MDA (55%, p < 0.05) and hs-CRP (53%, p < 0.05) and increased SOD (14%, p < 0.05), vitamin A (25%, p < 0.05), and vitamin E (65%, p < 0.05) in the experimental group. These phenomena were accompanied by increased aerobic capacity (17%, p < 0.05). The placebo group showed an increase in CK (5%, p < 0.05) and no significant change in LDH, SOD or vitamin A. MDA levels decreased (21%, p < 0.05) and vitamin E increased (14%, p < 0.05) in the placebo group, but to a much lesser extent than in the experimental group. These results show that sesame consumption may reduce muscle damage and oxidative stress while improving the aerobic capacity in soccer players.

8.
Int J Biol Macromol ; 94(Pt A): 271-282, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27737777

RESUMO

A lectin from Canavalia virosa, Diocleinae subtribe, was purified by affinity chromatography with Sephadex G-50 matrix and named ConV. The primary structure of ConV was obtained by mass spectrometry and crystals were obtained by the vapor diffusion method at 293K and belonged to orthorhombic space group P21221 with two molecules in its asymmetric unit. The structure obtained presented Rfactor and Rfree of 18.91% and 24.92% respectively, with no residues in nonallowed regions of Ramachandran plot. The crystal structure was solved at 2.53Å and was demonstrated to be very similar to other lectins from the same subtribe. In inflammatory tests, ConV elicited paw edema, but incubation of lectin with glucose beforehand was able to reduce the edematogenic effect, indicating the involvement of the carbohydrate recognition domain in this process. The lectin also showed toxicity to rat C6 glioma cells, disrupting the mitochondrial membrane potential (ΔYm) and decreasing cell viability, indicating an anticancer potential for ConV. In silico studies confirmed that ConV interacts strongly with carbohydrates that comprise the N-glycans of glycoproteins. This finding corroborates the hypothesis which holds that the lectin domain interacts with glycans in molecular targets and that this contributes to the effects observed in biological activities.


Assuntos
Anti-Inflamatórios/química , Antineoplásicos Fitogênicos/química , Extratos Vegetais/química , Sequência de Aminoácidos , Animais , Anti-Inflamatórios/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Sítios de Ligação , Canavalia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sequência Conservada , Cristalografia por Raios X , Ensaios de Seleção de Medicamentos Antitumorais , Ligação de Hidrogênio , Masculino , Manosídeos/química , Camundongos , Simulação de Acoplamento Molecular , Extratos Vegetais/farmacologia , Lectinas de Plantas/química , Ligação Proteica , Conformação Proteica em Folha beta , Estrutura Quaternária de Proteína , Ratos , Sementes/química
9.
Int J Biol Macromol ; 92: 194-201, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27411295

RESUMO

The relation structure-activity of the Mimosoideae lectins of Parkia platycephala (PPL) and Parkia biglobosa (PBL) was analyzed in this study. PBL was solved by X-ray crystallography at a resolution of 2.1Å, and the crystal structure belonged to the C2221 space group. Structural organization and binding sites were also characterized. Specifically, PBL monomer consists of three ß-prism domains tandemly arranged with each one presenting a different carbohydrate recognition domain (CRD). PPL showed antinociceptive activity in the mouse model of acetic acid-induced writhes with maximal inhibitory effect by 74% at 1mg/mL. PPL also demonstrated anti-inflammatory effect causing inhibition of leukocyte migration induced by both direct and indirect chemoattractants. These PPL activities were compared to that of PBL described previously. Molecular docking of both PBL and PPL demonstrated some differences in carbohydrate-lectin interaction energy. Comparing structure and biological effects of the two lectins provided new data about their structure and the relation with its biological activities.


Assuntos
Fabaceae/química , Lectinas/química , Lectinas/farmacologia , Sequência de Aminoácidos , Analgésicos/farmacologia , Animais , Anti-Inflamatórios/farmacologia , Sítios de Ligação , Movimento Celular/efeitos dos fármacos , Leucócitos/citologia , Camundongos , Simulação de Acoplamento Molecular , Domínios Proteicos , Estrutura Secundária de Proteína , Alinhamento de Sequência , Eletricidade Estática
10.
Arch Biochem Biophys ; 596: 73-83, 2016 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-26946944

RESUMO

A glycosylated lectin (CTL) with specificity for mannose and glucose has been detected and purified from seeds of Centrolobium tomentosum, a legume plant from Dalbergieae tribe. It was isolated by mannose-sepharose affinity chromatography. The primary structure was determined by tandem mass spectrometry and consists of 245 amino acids, similar to other Dalbergieae lectins. CTL structures were solved from two crystal forms, a monoclinic and a tetragonal, diffracted at 2.25 and 1.9 Å, respectively. The carbohydrate recognition domain (CRD), metal-binding site and glycosylation site were characterized, and the structural basis for mannose/glucose-binding was elucidated. The lectin adopts the canonical dimeric organization of legume lectins. CTL showed acute inflammatory effect in paw edema model. The protein was subjected to ligand screening (dimannosides and trimannoside) by molecular docking, and interactions were compared with similar lectins possessing the same ligand specificity. This is the first crystal structure of mannose/glucose native seed lectin with proinflammatory activity isolated from the Centrolobium genus.


Assuntos
Edema/induzido quimicamente , Fabaceae/química , Lectina de Ligação a Manose , Simulação de Acoplamento Molecular , Lectinas de Plantas , Sementes/química , Sequência de Aminoácidos , Animais , Modelos Animais de Doenças , Edema/patologia , Feminino , Glicosilação , Inflamação/induzido quimicamente , Inflamação/patologia , Lectina de Ligação a Manose/química , Lectina de Ligação a Manose/toxicidade , Espectrometria de Massas , Lectinas de Plantas/química , Lectinas de Plantas/toxicidade , Pegadas de Proteínas , Ratos , Ratos Wistar , Relação Estrutura-Atividade
11.
Int J Biochem Cell Biol ; 72: 27-39, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26751394

RESUMO

Legume lectins are the most thoroughly studied group of lectins and have been widely linked to many pathological processes. Their use as immunohistochemistry markers for cell profiling and cancer diagnosis have made these molecules important tools for immunological studies and have stimulated the prospection and characterization of new lectins. The crystal structures of a recombinant seed lectin from Vatairea macrocarpa (rVML) and its complexes with GalNAcα1-O-Ser, GalNAc and α-lactose, have been determined at 1.90, 1.97, 2.70 and 1.83Å resolution, respectively. Small angle X-ray scattering and calorimetry assays have confirmed the same pH stable oligomerization pattern and binding profiles proposed for its wild-type counterpart. In silico analyzes have explored the potential of this recombinant lectin as new tool for cancer research through a comparative profile with other legume lectins widely used for cancer diagnosis and prognosis. The results suggest the recognition of specific epitopes exhibited on different cancer cells as a process that relies on the disposition of hydrophobic clusters and charged regions around the lectin carbohydrate-binding site, favouring the anchorage of different groups in the antigen boundaries, highlighting the different potential of each analyzed lectin. In conclusion, the experimental results and comparative analysis show that rVML is as a promising tool for cancer research, able to bind with high affinity specific tumor-associated antigens, highly stable and easily produced.


Assuntos
Antígenos Glicosídicos Associados a Tumores/metabolismo , Fabaceae/química , Neoplasias/metabolismo , Lectinas de Plantas/química , Lectinas de Plantas/metabolismo , Acetilgalactosamina/metabolismo , Lactose/metabolismo , Simulação de Acoplamento Molecular , Ligação Proteica , Conformação Proteica
12.
Int J Biol Macromol ; 82: 464-70, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26499084

RESUMO

Lectins are proteins that show a variety of biological activities. However, they share in common at least one domain capable of recognizing specific carbohydrates reversibly without changing its structure. The legume lectins family is the most studied family of plant lectins, in particular the Diocleinae subtribe, which possesses high degree of structural similarity, but variable biological activities. This variability lies in small differences that can be analyzed in studies based on structures. In particular, Dioclea sclerocarpa seed lectin (DSL) presents low ability to relax endothelialized rat aorta in comparison with other Dioclea lectins such as Dioclea violacea (DVL), Dioclea virgata (DvirL) and Dioclea rostrata (DRL). The DSL relaxation mechanism relies on nitric oxide production and carbohydrate recognition domain (CRD). This feature can be explained by structural differences, since DSL has a carbohydrate recognition domain design less favorable. In addition, the presence of a glutamate residue at position 205 proved to be a decisive factor for the low relaxant effect of Dioclea lectins.


Assuntos
Dioclea/química , Lectinas de Plantas/química , Lectinas de Plantas/farmacologia , Vasodilatadores/química , Vasodilatadores/farmacologia , Animais , Aorta/efeitos dos fármacos , Sítios de Ligação , Carboidratos/química , Modelos Moleculares , Lectinas de Plantas/isolamento & purificação , Ligação Proteica , Conformação Proteica , Ratos , Relação Estrutura-Atividade , Vasodilatadores/isolamento & purificação
13.
J Mol Recognit ; 29(4): 134-41, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26464029

RESUMO

A novel lectin present in Dioclea reflexa seeds (DrfL) was discovered and described in this study. DrfL was purified in a single step by affinity chromatography in a Sephadex G-50 column. The lectin strongly agglutinated rabbit erythrocytes and was inhibited by α-methyl-D-mannoside, D-mannose, and D-glucose. The hemagglutinating activity of DrfL is optimum at pH 5.0-7.0, stable up to 50 °C, and dependent on divalent cations. Similar to other lectins of the subtribe Diocleinae, the analysis by mass spectrometry indicated that DrfL has three chains (α, ß, and γ) with masses of 25,562, 12,874, and 12,706 Da, respectively, with no disulfide bonds or glycosylation. DrfL showed inflammatory activity in the paw edema model and exhibited low cytotoxicity against Artemia sp.


Assuntos
Dioclea/química , Edema/induzido quimicamente , Manose/farmacologia , Lectinas de Plantas/isolamento & purificação , Lectinas de Plantas/farmacologia , Animais , Cromatografia de Afinidade , Eritrócitos/efeitos dos fármacos , Hemaglutinação/efeitos dos fármacos , Mediadores da Inflamação/isolamento & purificação , Mediadores da Inflamação/farmacologia , Camundongos , Lectinas de Plantas/química , Estrutura Secundária de Proteína , Coelhos
14.
Arch Biochem Biophys ; 588: 33-40, 2015 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-26545483

RESUMO

A novel lectin from seeds of Clathrotropis nitida (CNA) was purified and characterized. CNA is a glycoprotein containing approximately 3.3% carbohydrates in its structure. CNA promoted intense agglutination of rabbit erythrocytes, which was inhibited by galactosides and porcine stomach mucin (PSM). The lectin maintained its hemagglutinating activity after incubation in a wide range of temperatures (30-60 °C) and pH (6.0-7.0), and its binding activity was dependent on divalent cations (Ca(+2) and Mg(+2)). SDS-PAGE showed an electrophoretic profile consisting of a single band of 28 kDa, as confirmed by electrospray ionization mass spectrometry, which indicated an average molecular mass of 27,406 ± 2 Da and the possible presence of isoforms and glycoforms. In addition, CNA exhibited no toxicity to Artemia sp. nauplii and elicited reversible and dose-dependent vasorelaxation in precontracted aortic rings. CNA was successfully immobilized on chitosan beads and was able to capture PSM in solution. This study demonstrated that CNA is a lectin that has potential as a biotechnological tool in glycomics and glycoproteomics applications.


Assuntos
Fabaceae/química , Lectinas de Plantas/isolamento & purificação , Lectinas de Plantas/farmacologia , Vasodilatadores/isolamento & purificação , Vasodilatadores/farmacologia , Sequência de Aminoácidos , Animais , Aorta Torácica/efeitos dos fármacos , Aorta Torácica/fisiologia , Artemia/efeitos dos fármacos , Quitosana , Fabaceae/genética , Hemaglutinação/efeitos dos fármacos , Humanos , Proteínas Imobilizadas/química , Técnicas In Vitro , Masculino , Dados de Sequência Molecular , Peso Molecular , Lectinas de Plantas/genética , Plantas Medicinais/química , Plantas Medicinais/genética , Coelhos , Ratos , Ratos Wistar , Sementes/química , Homologia de Sequência de Aminoácidos , Vasodilatadores/química
15.
Braz. arch. biol. technol ; 58(3): 414-420, May-Jun/2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-748210

RESUMO

Gastric cancer (GC) is a multifactorial disease with a high mortality rate in Brazil and worldwide. This work aimed to evaluate single nucleotide polymorphisms (SNP) rs1695, in the Glutathione S-Transferase Pi (GSTP1) gene in GC samples by comparative analysis Specific PCR - ASP and Dideoxy Single Allele-Specific PCR - DSASP methods. The DSASP is the proposed new method for allelic discrimination. This work analyzed 60 GC samples, 26 diffuse and 34 intestinal types. The SNP rs1695 of the GSTP1 gene was significantly associated with GC analyzed by DSASP method (χ2 = 9.7, P < 0.05). A comparative analysis of the data obtained from both methods did not differ significantly (χ2 = 0.08, P > 0.05). These results suggest that the SNP rs1695 of the GSTP1 gene was a risk factor associated with gastric carcinogens is and the DSASP method was a new successfully low-cost strategy to study allelic discrimination.

16.
An Acad Bras Cienc ; 87(2): 973-84, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25993359

RESUMO

Twenty species of marine invertebrates from the Brazilian coast were screened for hemagglutinating/hemolytic activity. In at least twelve tested species, hemagglutinating activity was different for different blood types, suggesting the presence of lectins. Extracts from four species showed hemolytic activity. Two new lectins were purified from the marine sponge Cliona varians (CvL-2) and sea cucumber Holothuria grisea (HGL). CvL-2 was able to agglutinate rabbit erythrocytes and was inhibited by galactosides. The hemagglutinating activity was optimal in pH neutral and temperatures below 70 °C. CvL-2 is a trimeric protein with subunits of 175 kDa. On the other hand, HGL showed both hemagglutinating and hemolytic activity in human and rabbit erythrocytes, but hemolysis could be inhibited by osmotic protection, and agglutination was inhibited by mucin. HGL was stable in pH values ranging from 4 to 10 and temperatures up to 90 °C. In electrophoresis and gel filtration, HGL was a monomeric protein with 15 kDa. CvL-2 and HGL showed different levels of toxicity to Artemia naplii. CvL-2 showed LC50 of 850.1 µg/mL, whereas HGL showed LC50 of 9.5 µg/mL.


Assuntos
Eritrócitos/efeitos dos fármacos , Hemaglutinação/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Lectinas/farmacologia , Poríferos/química , Pepinos-do-Mar/química , Animais , Artemia/efeitos dos fármacos , Brasil , Testes de Hemaglutinação , Humanos , Lectinas/classificação , Lectinas/isolamento & purificação , Poríferos/classificação , Coelhos , Pepinos-do-Mar/classificação
17.
J Mol Recognit ; 28(5): 285-92, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25706245

RESUMO

In this study, the amino acid sequence and anti-inflammatory effect of Bauhinia bauhinioides (BBL) lectin were evaluated. Tandem mass spectrometry revealed that BBL possesses 86 amino acid residues. BBL (1 mg/kg) intravenously injected in rats 30 min prior to inflammatory stimuli inhibited the cellular edema induced by carrageenan in only the second phase (21% - 3 h, 19% - 4 h) and did not alter the osmotic edema induced by dextran. BBL also inhibited carrageenan peritoneal neutrophil migration (51%), leukocyte rolling (58%) and adhesion (68%) and the neutrophil migration induced by TNF-α (64%). These effects were reversed by the association of BBL with galactose, demonstrating that the carbohydrate-binding domain is essential for lectin activity. In addition, BBL reduced myeloperoxidase activity (84%) and TNF-α (68%) and IL1-ß (47%) levels. In conclusion, the present investigation demonstrated that BBL contains highly homologous isolectins, resulting in a total of 86 amino acid residues, and exhibits anti-inflammatory activity by inhibiting neutrophil migration by reducing TNF-α and IL1-ß levels via the lectin domain.


Assuntos
Anti-Inflamatórios/farmacologia , Bauhinia/química , Galectinas/farmacologia , Neutrófilos/fisiologia , Extratos Vegetais/farmacologia , Lectinas de Plantas/farmacologia , Sequência de Aminoácidos , Animais , Anti-Inflamatórios/química , Adesão Celular , Citocinas/fisiologia , Avaliação Pré-Clínica de Medicamentos , Galectinas/química , Migração e Rolagem de Leucócitos , Dados de Sequência Molecular , Neutrófilos/efeitos dos fármacos , Peritonite/imunologia , Extratos Vegetais/química , Lectinas de Plantas/química , Ratos Wistar , Sementes/química
18.
Arch Biochem Biophys ; 565: 32-9, 2015 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-25444858

RESUMO

Lectins are proteins able to recognize carbohydrates, without modifying their structure, via the carbohydrate-recognition domain (CRD). Here, the three-dimensional structure of the mannose-binding lectin isolated from Cymbosema roseum (CRLI) was determined with X-man molecule modeled into the carbohydrate recognition domain. CRLI relaxant activity in thoracic rat aorta was also investigated, and based on the results, a molecular docking of CRLI with heparan sulfate was performed to investigate the possible interaction with mechanoreceptors involved in vasorelaxation. CRLI (IC50=12.4 µg mL(-)(1)) elicited vasorelaxant response (96%) in endothelialized rat aorta contracted with phenylephrine. Endothelium-derived relaxant factors, extracellular calcium (Ca(2+)e) and muscarinic receptors were also evaluated as putative participants in the CRLI relaxant effect. CRLI relaxant effect was blocked by L-NAME, a nonselective inhibitor of nitric oxide synthase (NOS), and partially inhibited in a calcium-free solution (0Ca) and by atropine, but it remained unchanged in the presence of indomethacin and TEA. In summary, our data suggest interaction between CRLI and muscarinic receptors located in vascular endothelial cells leading to NOS activation triggered by a mechanism that involves Ca(2+)e along with the ability of CRLI to interact with heparan sulfate, a highly rated mechanoreceptor involved in eNOS activation.


Assuntos
Fabaceae/química , Lectina de Ligação a Manose/farmacologia , Relaxamento Muscular/efeitos dos fármacos , Músculo Liso Vascular/enzimologia , Óxido Nítrico Sintase Tipo III/metabolismo , Proteínas de Plantas/farmacologia , Receptores Muscarínicos/metabolismo , Animais , Anti-Inflamatórios não Esteroides/farmacologia , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Humanos , Indometacina/farmacologia , Masculino , Lectina de Ligação a Manose/química , Músculo Liso Vascular/citologia , NG-Nitroarginina Metil Éster/farmacologia , Óxido Nítrico/biossíntese , Óxido Nítrico Sintase Tipo III/antagonistas & inibidores , Proteínas de Plantas/química , Ratos , Ratos Wistar
19.
Int J Biol Macromol ; 72: 1368-75, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25312602

RESUMO

A new chromophore-containing agglutinin (Haliclona manglaris agglutinin (HMA)) was isolated from the tropical sponge H. manglaris. HMA was purified by a combination of hydrophobic interaction chromatography and ion exchange chromatography. Native HMA is a heterotrimer formed by two ß-chains (15 kDa) and one α-chain (22 kDa). HMA is a glycoprotein and possesses three intrachain disulfide bonds. Hemagglutinating activity of HMA was stable at neutral pH and temperatures up to 60 °C. HMA was only inhibited by thyroglobulin. Mass spectrometry sequencing and Edman degradation revealed a unique amino acid sequence of about 30%. Moreover, HMA has an organic chromophore of 581 Da, and this characteristic seems to be important to its antioxidant activity. Interestingly, while HMA showed no toxicity against Artemia nauplii and was unable to agglutinate bacterial cells, it did show a high capacity to protect ß-carotene against oxidation. Thus, our findings suggest the putative involvement of HMA in the protection of the sponge against oxidation.


Assuntos
Aglutininas/química , Aglutininas/isolamento & purificação , Corantes Fluorescentes/química , Haliclona/química , Sequência de Aminoácidos , Animais , Antioxidantes/farmacologia , Artemia/efeitos dos fármacos , Carboidratos/análise , Cátions Bivalentes/farmacologia , Cromatografia em Gel , Cromatografia de Fase Reversa , Eletroforese em Gel de Poliacrilamida , Hemaglutinação/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Dados de Sequência Molecular , Peso Molecular , Peptídeos/química , Coelhos , Análise de Sequência de Proteína , Compostos de Sulfidrila/química , Espectrometria de Massas em Tandem , Temperatura
20.
Int J Biol Macromol ; 72: 1136-42, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25192853

RESUMO

Resveratrol can also inhibit the activation of proinflammatory mediators and cytokines at the early gene expression stage. It is well known that lectins are sugar-binding proteins that act as both pro- and anti-inflammatory molecules. Thus, the objective of this work was to verify the binding of a polyphenol compound with a lectin of Canavalia maritima (ConM) based on their ability to inhibit pro-inflammatory processes. To accomplish this, ConM was purified and crystallized, and resveratrol was soaked at 5mM for 2h of incubation. The crystal belongs to the monoclinic space group C2, the final refinement resulted in an Rfactor of 16.0% and an Rfree of 25.5%. Resveratrol binds in the rigid ß-sheet through H-bonds and hydrophobic interaction with amino acids that compose the fifth and sixth ß-strands of the rigid ß-sheet of ConM. The ConM and resveratrol inhibited DPPH oxidation, showing synergic activity with the most effective ratio of 2:3 and carbohydrate binding site is not directly related to antioxidant activity. It is the interaction between ConM and resveratrol that indicates the synergism of these two molecules in acting as free radicals scavengers and in reducing the inflammatory process through the inhibition of many pro-inflammatory events.


Assuntos
Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Lectinas de Plantas/química , Lectinas de Plantas/metabolismo , Polifenóis/química , Polifenóis/metabolismo , Estilbenos/química , Estilbenos/metabolismo , Sítios de Ligação , Compostos de Bifenilo/química , Canavalia , Cristalografia por Raios X , Sequestradores de Radicais Livres/farmacologia , Glicosilação/efeitos dos fármacos , Ligação de Hidrogênio/efeitos dos fármacos , Interações Hidrofóbicas e Hidrofílicas/efeitos dos fármacos , Simulação de Acoplamento Molecular , Picratos/química , Ligação Proteica/efeitos dos fármacos , Estrutura Secundária de Proteína , Quercetina/farmacologia , Resveratrol
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