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71.
Yasmin Silva Rizk Alice Fischer Marillin de Castro Cunha Patrik Oening Rodrigues Maria Carolina Silva Marques Maria de Fátima Cepa Matos M?nica Cristina Toffoli Kadri Carlos Alexandre Carollo Carla Cardozo Pinto de Arruda 《Memórias do Instituto Oswaldo Cruz》2014,109(8):1050-1056
This study is the first phytochemical investigation of Selaginella sellowii
and demonstrates the antileishmanial activity of the hydroethanolic extract
from this plant (SSHE), as well as of the biflavonoids amentoflavone and
robustaflavone, isolated from this species. The effects of these substances were
evaluated on intracellular amastigotes of Leishmania (Leishmania)
amazonensis, an aetiological agent of American cutaneous leishmaniasis.
SSHE was highly active against intracellular amastigotes [the half maximum inhibitory
concentration (IC50) = 20.2 µg/mL]. Fractionation of the extract led to the isolation
of the two bioflavonoids with the highest activity: amentoflavone, which was about
200 times more active (IC50 = 0.1 μg/mL) and less cytotoxic than SSHE (IC50 = 2.2 and
3 μg/mL, respectively on NIH/3T3 and J774.A1 cells), with a high selectivity index
(SI) (22 and 30), robustaflavone, which was also active against L.
amazonensis (IC50 = 2.8 µg/mL), but more cytotoxic, with IC50 = 25.5
µg/mL (SI = 9.1) on NIH/3T3 cells and IC50 = 3.1 µg/mL (SI = 1.1) on J774.A1 cells.
The production of nitric oxide (NO) was lower in cells treated with amentoflavone
(suggesting that NO does not contribute to the leishmanicidal mechanism in this
case), while NO release was higher after treatment with robustaflavone. S.
sellowii may be a potential source of biflavonoids that could provide
promising compounds for the treatment of cutaneous leishmaniasis. 相似文献
72.
Bezerra EH Rocha BA Nagano CS Bezerra Gde A Moura TR Bezerra MJ Benevides RG Sampaio AH Assreuy AM Delatorre P Cavada BS 《Biochemical and biophysical research communications》2011,(4):566-570
Diocleinae lectins are highly homologous in their primary structure which features metal binding sites and a carbohydrate recognition domain (CRD). Differences in the biological activity of legume lectins have been widely investigated using hemagglutination inhibition assays, isothermal titration microcalorimetry and co-crystallization with mono- and oligosaccharides. Here we report a new lectin crystal structure (ConBr) extracted from seeds of Canavalia brasiliensis, predict dimannoside binding by docking, identify the α-aminobutyric acid (Abu) binding pocket and compare the CRD of ConBr to that of homologous lectins. Based on the hypothesis that the carbohydrate affinity of lectins depends on CRD configuration, the relationship between tridimensional structure and endothelial NO synthase activation was used to clarify differences in biological activity. Our study established a correlation between the position of CRD amino acid side chains and the stimulation of NO release from endothelium. 相似文献
73.
Moustacas VS Zaffalon FG Lagares MA Loaiza-Eccheverri AM Varago FC Neves MM Heneine LG Arruda RP Henry M 《Theriogenology》2011,75(2):300-307
The objective was to evaluate the suitability of using natural or lyophilized low density lipoproteins (LDL), in lieu of whole egg yolk, in extenders for cryopreserving ram semen. Once extragonadal sperm reserves were depleted in 10 fertile Santa Inês cross rams, two ejaculates per ram were collected for cryopreservation. Nine extenders were used: Tris-16% egg yolk extender with 5% glycerol as a control (T1), and substitution of whole egg yolk with 8, 12, 16 or 20% natural LDL (T2-T5, respectively), or with 8, 12, 16, or 20% lyophilized LDL (T6-T9). Semen was diluted to 100 × 106 sperm/mL, packaged into 0.25 mL straws, cooled, held at 5 °C for 3 h, and then frozen in liquid nitrogen vapor. Immediately after thawing (37 °C for 30 s), sperm total and progressive motility, and kinetic parameters were analyzed with computer assisted semen analysis (CASA). Percentage of sperm with plasma membrane functional integrity was assessed by the hypoosmotic swelling test (HOST), sperm membrane physical integrity with propidium iodide (PI), and acrosome integrity with FITC-PSA using an epifluorescent microscope. For all sperm end points, there was no difference between the control and natural LDL treatments (P > 0.05): total motility (T1: 20.9 ± 11.9 and average of T2-T5: 25.9 ± 13.6%; mean ± SD), progressive motility (T1: 6.6 ± 4.2 and average of T2-T5: 11.7 ± 7.5%), HOST+ (T1: 23.7 ± 6.9 and average of T2-T5: 23.2 ± 8.7 %) and PI−/PSA− (T1: 13.8 ± 7.8 and average of T2-T5: 18.1 ± 7.8%). However, lyophilization was apparently unable to preserve the protective function of LDL; every sperm end point was significantly worse than in the control and natural LDL groups. We concluded that natural LDL was appropriate for cryopreserving ram semen, as it yielded results similar to those obtained with whole egg yolk. 相似文献
74.
Simões PS Perosa SR Arganãraz GA Yacubian EM Carrete H Centeno RS Varella PP Santiago JF Canzian M Silva JA Mortara RA Amado D Cavalheiro EA Mazzacoratti Mda G 《Neurochemistry international》2011,58(4):477-482
Kallikrein 1 (hK1) is a tissue enzyme responsible for kinin release in inflammatory cascade. This study was delineated to study the distribution and the co-localization of hK1 and kinin B1 and B2 receptors with glial and/or neuronal proteins markers, in the hippocampus of patients with refractory temporal lobe epilepsy, associated with hippocampal sclerosis (TLE-HS), comparing with control tissues. Hippocampal levels of KLK1 mRNA were also measured. hK1, kinin B1 and B2 receptors, NeuN and GFAP were analyzed using immunohistochemistry and confocal microscopy and KLK1 mRNA was quantified with real time PCR. Increased expression of hK1 by astrocytes co-localized with GFAP was found, contrasting with kinin B1 and B2 receptors, which were co-localized with NeuN in the sclerotic hippocampus. In addition, KLK1 mRNA was also up-regulated in same tissues. These data suggest an overexpression of kallikrein-kinin system and a neuron-glia interaction in the inflammatory process present in refractory TLE-HS. 相似文献
75.
G M Nardi R Felippi S DalBó J M Siqueira-Junior D C Arruda F Delle Monache A K Timbola M G Pizzolatti K Ckless R M Ribeiro-do-valle 《Phytomedicine》2003,10(2-3):176-184
Croton celtidifolius Baill commonly known as "sangue-de-adave" is a tree found in the Atlantic Forest of south of Brazil, mainly in Santa Catarina. The bark and leaf infusions of this medicinal plant have been popularly used for the treatment of inflammatory diseases. In this study we evaluated the anti-inflammatory and antioxidant properties of crude extract (CE), aqueous fraction (AqF), ethyl acetate fraction (EAF), butanolic fraction (BuF) and catechin, gallocatechin and sub-fractions, 19SF, 35SF and 63SF that contained a mixture of proanthocyanidins and were derived from the EAF fraction. The CE, AqF, EAF, BuF, catechin and sub-fractions 35SF and 63SF reduced paw edema induced by carrageenan. The CE, fractions, sub-fractions and isolated compounds showed antioxidant properties in vitro, all were able to scavenge superoxide anions at a concentration of 100 microg ml(-1). The EAF, catechin and gallocatechin were most effective in the deoxyribose assay, IC50 0.69 (0.44-1.06), 0.20 (0.11-0.39), 0.55 (0.28-1.08) microg x ml(-1) respectively. The CE and other fractions and sub-fractions inhibited deoxyribose degradation up to 1 microg x ml(-1). In the hydrophobic system only AqF did not show lipid peroxidation inhibition. The CE, other fractions, sub-fractions and isolated compounds inhibited lipidid peroxidation only at a concentration of 100 microg x ml(-1). In summary, this study demonstrates that Croton celtidifolius bark has significant anti-inflammatory and antioxidant activity. 相似文献
76.
Rogério Fraga Troian Andrei Stecca Steindorff Marcelo Henrique Soller Ramada Walquiria Arruda Cirano José Ulhoa 《Biotechnology letters》2014,36(10):2095-2101
Trichoderma spp. are known for their biocontrol activity against several plant pathogens. A specific isolate of Trichoderma harzianum, 303/02, has the potential to inhibit the growth of Sclerotinia sclerotiorum, an important agent involved in several crop diseases. In this study, the interaction between T. harzianum 303/02 and mycelia, sclerotia and apothecia of S. sclerotiorum was studied by scanning electron microscopy. RT-qPCR was used to examine the expression of 11 genes potentially involved in biocontrol. T. harzianum 303/02 parasitizes S. sclerotiorum by forming branches that coil around the hyphae. The fungus multiplied abundantly at the sclerotia and apothecia surface, forming a dense mycelium that penetrated the inner surface of these structures. The levels of gene expression varied according to the type of structure with which T. harzianum was interacting. The data also showed the presence of synergistic action between the cell-wall degrading enzymes. 相似文献
77.
Purification,characterization and partial sequence of a pro‐inflammatory lectin from seeds of Canavalia oxyphylla Standl. & L. O. Williams 下载免费PDF全文
Mayara Q. Santiago Cintia C. F. Leitão Francisco N. Pereira‐Junior Vanir R. Pinto‐Junior Vinicius J. S. Osterne Claudia F. Lossio João B. Cajazeiras Helton C. Silva Francisco V. S. Arruda Livia P. Pereira Ana M. S. Assreuy Kyria S. Nascimento Celso S. Nagano Benildo S. Cavada 《Journal of molecular recognition : JMR》2014,27(3):117-123
Recent studies have shown that lectins are promising tools for use in various biotechnological processes, as well as studies of various pathological mechanisms, isolation, and characterization of glycoconjugates and understanding the mechanisms underlying pathological mechanisms conditions, including the inflammatory response. This study aimed to purify, characterize physicochemically, and predict the biological activity of Canavalia oxyphylla lectin (CoxyL) in vitro and in vivo. CoxyL was purified by a single‐step affinity chromatography in Sephadex® G‐50 column. Sodium dodecyl sulfate polyacrylamide gel electrophoresis showed that the pure lectin consists of a major band of 30 kDa (α‐chain) and two minor components (β‐chain and γ‐chain) of 16 and 13 kDa, respectively. These data were further confirmed by electrospray ionization mass spectrometry, suggesting that CoxyL is a typical ConA‐like lectin. In comparison with the average molecular mass of α‐chain, the partial amino acid sequence obtained corresponds to approximately 45% of the total CoxyL sequence. CoxyL presented hemagglutinating activity that was specifically inhibited by monosaccharides (D‐glucose, D‐mannose, and α‐methyl‐D‐mannoside) and glycoproteins (ovalbumin and fetuin). Moreover, CoxyL was shown to be thermostable, exhibiting full hemagglutinating activity up to 60°C, and it was pH‐sensitive for 1 h, exhibiting maximal activity at pH 7.0. CoxyL caused toxicity to Artemia nauplii and induced paw edema in rats. This biological activity highlights the importance of lectins as important tools to better understand the mechanisms underlying inflammatory responses. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
78.
Alexandre Medeiros do Carmo Fabiana Maria Santos Carmen Lucia Ortiz-Agostinho Iêda Nishitokukado Cintia S. Frota Flavia Ubeda Gomes André Zonetti de Arruda Leite Claudio Sérgio Pannuti Lucy Santos Vilas Boas Magaly Gemio Teixeira Aytan Miranda Sipahi 《PloS one》2014,9(11)
Background
Cytomegalovirus is highly prevalent virus and usually occurs in immunocompromised patients. The pathophysiology and treatment of inflammatory bowel disease often induce a state of immunosuppression. Because this, there are still doubts and controversies about the relationship between inflammatory bowel disease and cytomegalovirus.Aim
Evaluate the frequency of cytomegalovirus in patients with inflammatory bowel disease and identify correlations.Methods
Patients with inflammatory bowel disease underwent an interview, review of records and collection of blood and fecal samples. The search for cytomegalovirus was performed by IgG and IgM blood serology, by real-time PCR in the blood and by qualitative PCR in feces. Results were correlated with red blood cell levels, C-reactive protein levels, erythrocyte sedimentation rates and fecal calprotectin levels for each patient.Results
Among the 400 eligible patients, 249 had Crohn''s disease, and 151 had ulcerative colitis. In the group of Crohn''s disease, 67 of the patients had moderate or severe disease, but 126 patients presented with active disease, based on the evaluation of the fecal calprotectin. In patients with ulcerative colitis, only 21 patients had moderate disease, but 76 patients presented with active disease, based on the evaluation of the fecal calprotectin. A large majority of patients had positive CMV IgG. Overall, 10 patients had positive CMV IgM, and 9 patients had a positive qualitative detection of CMV DNA by PCR in the feces. All 400 patients returned negative results after the quantitative detection of CMV DNA in blood by real-time PCR. Analyzing the 19 patients with active infections, we only found that such an association occurred with the use of combined therapy (anti-TNF-alpha + azathioprine)Conclusion
The findings show that latent cytomegalovirus infections are frequent and active cytomegalovirus infection is rare. We did not find any association between an active infection of CMV and inflammatory bowel disease activity. 相似文献79.
M Green O S Ruiz F Kear J A Arruda 《Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine (New York, N.Y.)》1991,198(3):846-851
The Na-H antiporter of renal-brush border membranes is inhibited by cyclic AMP and stimulated by protein kinase C. The proximal tubule contains guanylate cyclase and is capable of cyclic GMP production. The effect of cGMP on renal Na-H antiporter activity was analyzed in phosphorylated brush border membranes by 22Na uptake in the presence or absence of 1 mM amiloride. 8-Bromo cyclic GMP (1 microM) increased the amiloride-sensitive 22Na uptake in control from 1.26 +/- 0.13 to 1.54 +/- 0.12 nmol/mg/protein/10 sec, P less than 0.01, without altering the amiloride-insensitive component. In the absence of exogenous ATP, cGMP also stimulated the amiloride-sensitive 22Na uptake, which can be explained by the presence of endogenous ATP in concentrations of up to 50 microM in the membranes. In ATP-depleted membrane vesicles, however, cGMP inhibited the amiloride-sensitive 22Na uptake. These data indicate that cGMP acts on the Na-H antiporter by at least two different mechanisms, one of which is ATP dependent. It is likely that cGMP-dependent protein kinase mediates the stimulatory effects seen in the presence of ATP, and the inhibition seen in ATP-depleted membranes results from cGMP direct action on the Na-H antiporter. 相似文献
80.
Distal urinary acidification is thought to be mediated by an H+-ATPase sensitive to N-ethylmaleimide and dicyclohexyl-carbodiimide. We have studied the effect of chronic metabolic acidosis (NH4Cl for 3 days) or respiratory acidosis (inhalation of 10% CO2 for 2 days) on the H+-ATPase of plasma membranes prepared from the medulla. The enzymatic assay for the H+-ATPase was performed in the presence of ouabain and oligomycin and in the absence of Ca. H+-transport activity was assessed by the quenching of acridine orange in the presence of ATP. The 15-25% sucrose gradient fraction was enriched 40-fold in enzymatic activity over the homogenate, and 8-fold in enzymatic activity and 4-fold in H+-transport activity over the fluffy fraction (38,000 X g). Metabolic acidosis (pH less than 7.31) or chronic hypercapnia (PCO2 greater than 66 mmHg; 1 mmHg = 133.3 Pa) was induced for 2-3 days. Both groups showed the same enrichment factor in enzymatic and H+-transport assays as the control rabbits. Enzymatic and H+-transport activities, however, were not different between animals with respiratory acidosis and controls. Kinetic studies failed to disclose an increase in Vmax (673 vs. 702 mumol/(mg protein.min] or a decrease in Km (0.43 vs. 0.48 mM) in chronic hypercapnia as compared with controls. Metabolic acidosis also failed to increase H+-ATPase activity. These data demonstrate that the H+-ATPase of renal medulla does not display the expected increase in activity during acidosis. The role of this H+-ATPase in the adaptation to acidosis remains to be determined. 相似文献