RESUMO
This study aims to evaluate the activity of AFAL in the models of paw edema and chemical nociception. AFAL was injected s.c. or i.v before s.c. injection of carrageenan or dextran in rats to evaluate its pro- or anti-edematogenic effect. The antinociceptive activity was investigated by AFAL i.v. administration in mice in the writhing and formalin tests. Results were expressed as Mean ± SEM and considered significant for p <0.05 (ANOVA). AFAL (0.1 and 1 mg/kg; s.c.) induced paw edema in 30 min, remained constant until the 3rd h, increasing paw volume by 2.9x and 3.4x, respectively, compared to saline. However, the lectin did not change the edema induced by carrageenan, dextran or formalin. AFAL reduced the number of writhes by 53% (0.1 mg/kg) 60% (1 mg/kg) and 74% (10 mg/kg), but had no effect at any phases of the formalin test. In conclusion, AFAL presents pro-inflammatory and antinociceptive activity.
Assuntos
Animais , Camundongos , Acacia , Lectinas de Plantas , Nociceptividade , InflamaçãoRESUMO
This study aims to evaluate the activity of AFAL in the models of paw edema and chemical nociception. AFAL was injected s.c. or i.v before s.c. injection of carrageenan or dextran in rats to evaluate its pro- or anti-edematogenic effect. The antinociceptive activity was investigated by AFAL i.v. administration in mice in the writhing and formalin tests. Results were expressed as Mean ± SEM and considered significant for p <0.05 (ANOVA). AFAL (0.1 and 1 mg/kg; s.c.) induced paw edema in 30 min, remained constant until the 3rd h, increasing paw volume by 2.9x and 3.4x, respectively, compared to saline. However, the lectin did not change the edema induced by carrageenan, dextran or formalin. AFAL reduced the number of writhes by 53% (0.1 mg/kg) 60% (1 mg/kg) and 74% (10 mg/kg), but had no effect at any phases of the formalin test. In conclusion, AFAL presents pro-inflammatory and antinociceptive activity.(AU)
Assuntos
Animais , Camundongos , Nociceptividade , Lectinas de Plantas , Acacia , InflamaçãoRESUMO
Lectins have been described as glycoproteins that reversibly and specifically bind to carbohydrates. Legume lectins isolated from the subtribe Diocleinae (Canavalia, Dioclea andCratylia) are structurally homologous with respect to their primary structures. The Diocleinae lectins of Canavalia brasiliensis, Dioclea guianensis andCanavalia ensiformis have been shown to distinctly alter physiological parameters in isolated rat kidneys. Thus, the aim of this study was to investigate the effect of Cratylia floribunda lectin (CFL) on renal hemodynamics and ion transport in rats. In isolated perfused kidneys, CFL (10 mg/mL, n=5) increased RPP, RVR and decreased %TK+, but did not change urinary flow, glomerular filtration rate, sodium or chloride tubular transport. In isolated perfused mesenteric bed, CFL (3 and 10 mg/mL/min; n=4) did not alter tissue basal tonus or tissue contraction by phenylephrine (1 mM/mL/min). In conclusion, the seed lectin of Cratylia floribunda increased renal hemodynamic parameters showing a kaliuretic effect. This effect could be of tubular origin, rather than a result from haemodynamic alterations.
As lectinas são descritas como (glico)proteínas que se ligam, especificamente e reversivelmente, a carboidratos. Lectinas de leguminosas isoladas da subtribo Diocleinae (Canavalia, Dioclea eCratylia) são estruturalmente homólogas em relação às suas estruturas primárias. Demonstrou-se que as lectinas de DiocleinaeCanavalia brasiliensis, Dioclea guianensis eCanavalia ensiformis alteram diferentemente parâmetros fisiológicos em rins isolados de ratos. Dessa maneira, o objetivo deste estudo foi investigar o papel da lectina de Cratylia floribunda (CFL) na hemodinâmica renal e no transporte de íons em ratos. Em rins isolados perfundidos, CFL (10 mg/mL, n=5) aumentou a pressão de perfusão renal, a resistência vascular renal e reduziu o percentual do transporte tubular de K+, mas não alterou o fluxo urinário, a taxa de filtração glomerular e o percentual de transporte tubular dos íons sódio e cloreto. No leito mesentérico isolado perfundido, CFL (3 e 10 mg/mL/min, n=4) não alterou o tônus basal ou a contração do tecido induzida por fenilefrina (1 mM/mL/min). Em conclusão, a lectina de sementes de Cratylia floribunda altera parâmetros hemodinâmicos renais, provavelmente de origem tubular, e não por alterações hemodinâmicas.
Assuntos
Ratos , Transporte de Íons , Lectinas de Plantas/análise , Dioclea , Hemodinâmica , Amilorida/análiseRESUMO
A novel lectin, HGA-2, was isolated from the sea cucumber Holothuria grisea. The protein was isolated by a single chromatographic step using a column of Guar Gum as affinity. HGA-2 showed an apparent molecular mass of 17 kDa and 34 kDa under reducing and nonreducing conditions, respectively. The hemagglutinating activity was specific for rabbit erythrocytes, showing no activity for human blood A, B and O. Its hemagglutinating activity was inhibited by carbohydrates containing galactose, with higher affinity for GalNAc and glycoprotein porcine stomach mucin (PSM). HGA-2 was stable at pH 6-10, significantly declining at pH 5 and a temperature of 40°C, with its activity being abolished at 100 °C. The HGA-2 protein was found to be Ca(2+)-dependent; it was highly toxic against Artemia nauplii and able to recognize and agglutinate cells of Escherichia coli. Amino acid sequences of tryptic peptides of HGA-2 strongly suggest that HGA-2 is a member of the C-type lectin family.
Assuntos
Aglutininas/química , Aglutininas/metabolismo , Escherichia coli/metabolismo , Galactosídeos/metabolismo , Holothuria/química , Lectinas/química , Lectinas/metabolismo , Aglutininas/isolamento & purificação , Aglutininas/toxicidade , Sequência de Aminoácidos , Animais , Hemaglutinação , Testes de Hemaglutinação , Humanos , Concentração de Íons de Hidrogênio , Íons , Lectinas/isolamento & purificação , Lectinas/toxicidade , Lectinas Tipo C , Dados de Sequência Molecular , Coelhos , Alinhamento de Sequência , TemperaturaRESUMO
Two new lectins named Halilectin 1 (H-1) and Halilectin 2 (H-2) were isolated from the marine sponge Haliclona caerulea using a combination of affinity chromatography on stroma fixed onto Sephadex G-25 and cation and anion exchange chromatography. H-1 is a monomeric protein with a molecular mass of 40 kDa estimated using sodium dodecyl sulfate polyacrylamide gel electrophoresis and 15 kDa estimated using a TSK gel. Conversely, H-2 is a homodimeric protein with 15 kDa monomers linked via weak interactions. H-1 more effectively agglutinates trypsinized rabbit erythrocytes, whereas H-2 more effectively agglutinates native rabbit erythrocytes. The hemagglutinating activity of H-1 could be not inhibited by any tested sugars, but H-2 was inhibited by orosomucoid and porcine stomach mucin. Neither lectin was dependent on divalent ions. H-1 was stable at basic pH range and temperatures up to 50 °C, whereas H-2 was stable at acid pH range and temperatures up to 80 °C. The H. caerulea lectins exhibited dose-dependent toxicity against Artemia nauplii. Additionally, 76% of the primary structure of H-2 was determined using tandem mass spectrometry to contain a unique amino acid sequence with no similarity to any members of the animal lectin family.
Assuntos
Haliclona/química , Lectinas/química , Lectinas/farmacologia , Poríferos/química , Sequência de Aminoácidos , Animais , Artemia/efeitos dos fármacos , Sequência de Bases , Cromatografia/métodos , Eritrócitos/efeitos dos fármacos , Hemaglutinação/efeitos dos fármacos , Testes de Hemaglutinação/métodos , Concentração de Íons de Hidrogênio , Dados de Sequência Molecular , Peso Molecular , Coelhos , Espectrometria de Massas em Tandem/métodos , TemperaturaRESUMO
Lectins are carbohydrate-binding proteins of non-imune origin. This group of proteins is distributed widely in nature and they have been found in viruses, microorganisms, plants and animals. Lectins of plants have been isolated and characterized according to their chemical, physical-chemical, structural and biological properties. Among their biological activities, we can stress its fungicidal action. It has been previously described the effect of the lectins Dviol, DRL, ConBr and LSL obtained from the seeds of leguminous plants on the growth of yeasts isolated from vaginal secretions. In the present work the experiments were carried out in microtiter plates and the results interpreted by both methods: visual observations and a microplate reader at 530nm. The lectin concentrations varied from 0.5 to 256µg/mL, and the inoculum was established between 65-70% of trammitance. All yeast samples isolated from vaginal secretion were evaluated taxonomically, where were observed macroscopic and microscopic characteristics to each species. The LSL lectin did not demonstrate any antifungal activity to any isolate studied. The other lectins DRL, ConBr and DvioL, showed antifungal potential against yeast isolated from vaginal secretion. These findings offering offer a promising field of investigation to develop new therapeutic strategies against vaginal yeast infections, collaborating to improve women's health.
Assuntos
Humanos , Feminino , Antifúngicos/análise , Antifúngicos/isolamento & purificação , Secreções Corporais , Lectinas de Plantas/análise , Lectinas de Plantas/isolamento & purificação , Lectinas/análise , Lectinas/isolamento & purificação , Leveduras/crescimento & desenvolvimento , Leveduras/isolamento & purificação , Vaginose Bacteriana , Métodos , PacientesRESUMO
Lectins are proteins that have the ability to bind specifically and reversibly to carbohydrates and glycoconjugates, without altering the structure of the glycosyl ligand. They are found in organisms such as viruses, plants and humans, and they have been shown to possess important biological activities. The objective of this study was to purify and characterize lectins in the seeds of Clitoria fairchildiana, as well as to verify their biological activities. The results indicated the presence of a lectin (CFAL) in the glutelin acid protein fraction, which agglutinated native rabbit erythrocytes. CFAL was purified by column chromatography ion-exchange, DEAE-Sephacel, which was obtained from a peak of protein retained in the matrix by applying 0.5 M NaCl using the step-wise method. Electrophoretic analysis of this lectin in SDS-PAGE indicated a two band pattern protein molecular mass of approximately 100 and 116 kDa. CFAL proved to be unspecific to all carbohydrates/glycoconjugates in common use for the sugar inhibition test. This lectin showed no significant cytotoxicity to human red blood cells. It was observed that CFAL has anti-inflammatory activity in the paw edema induced by carrageenan model, in which a 64% diminution in edema was observed. Antinociceptive effects were observed for CFAL in the abdominal writhing test (induced by acetic acid), in which increasing doses of the lectin caused reduction in the number of contortions by up to 72%. It was concluded that the purified and characterized lectin from the seeds of Clitoria fairchildiana has anti-inflammatory and antinociceptive activity, and is not cytotoxic to human erythrocytes.
Assuntos
Analgésicos/farmacologia , Anti-Inflamatórios/farmacologia , Clitoria/química , Extratos Vegetais/farmacologia , Lectinas de Plantas/farmacologia , Sementes/química , Analgésicos/isolamento & purificação , Animais , Anti-Inflamatórios/isolamento & purificação , Carragenina , Eritrócitos/efeitos dos fármacos , Hemaglutinação , Humanos , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Camundongos , Nociceptividade/efeitos dos fármacos , Extratos Vegetais/isolamento & purificação , Lectinas de Plantas/isolamento & purificação , Coelhos , Ratos WistarRESUMO
DwL, a lectin extracted from the seeds of Dioclea wilsonii, is a metalloprotein with strong agglutinating activity against rabbit and ABO erythrocytes, inhibited by glucose and mannose. DwL was purified by affinity chromatography on a Sephadex G-50 column and ion exchange chromatography on a HiTrap SP XL column. SDS-PAGE revealed three electrophoretic bands corresponding to the α (25,634 ± 2 Da), ß (12,873 ± 2 Da) and γ (12,779 ± 2 Da) chains. Protein sequencing was done by Tandem Mass Spectrometry. The primary sequence featured 237 amino acids and was highly homologous to other reported Diocleinae lectins. A complete X-ray dataset was collected at 2.0 Å for X-Man-complexed DWL crystals produced by the vapor diffusion method. The crystals were orthorhombic and belonged to the space group I222, with the unit-cell parameters a = 59.6, b = 67.9 and c = 109.0 Å. DWL differed in potency from other ConA-like lectins and was found to induce neutrophil migration in rats, making it particularly useful in structural/functional studies of this class of proteins.