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Artigos

2016

Maia, L. F.; Gonzaga, T. A.; Carvalho, R. G.; Leite, C. M.; Lobo-Hajdu, G.; Aguiar, J.A.K.; Edwards, H. G.; Oliveira, L. F. C. . Monitoring Of Sulfated Polysaccharide Content In Marine Sponges By Raman Spectroscopy. Vibrational Spectroscopy (Print), V. 87, P. 149-156, 2016. https://doi.org/10.1016/j.vibspec.2016.10.002 (Arquivo PDF 1-s2.0-S0924203116302843-main)

Abstract

In this work sulfated polyssacharides from the marine sponges Polymastia janeirensis, Echinodictyum dendroides and Dragmacidon reticulatum have been analyzed by Raman spectroscopy as well as by biochemical analysis. The results showed that Raman spectroscopy can be applied as a screening method in monitoring the separation of ionic compounds such as sulfated polysaccharides in marine biological systems. The technique has been proven to be suitable in identifying sulfated polysaccharides rather than glycosaminoglycans from sponge tissues.

2015

– Cunha, A. L.; Oliveira, L. G.; Maia, L. F.; Oliveira, L. F. C.; Michelacci, Y. M.; Aguiar, J. A. K.. . Pharmaceutical Grade Chondroitin Sulfate: Structural Analysis And Identification Of Contaminants In Different Commercial Preparations. Carbohydrate Polymers, V. 134, P. 300-308, 2015. https://doi.org/10.1016/j.carbpol.2015.08.006 (Arquivo PDF 1-s2.0-S014486171500747X-main)

Abstract

The aim of the present study was to characterize 16 pharmaceutical grade chondroitin sulfate (CS) samples, concerning the structure and presence of contaminants, in comparison to USP and analytical grade CS. Agarose gel electrophoresis has shown that only 5 samples were >90% CS, while 11 contained less than 15% CS. FACE (fluorophore-assisted carbohydrate electrophoresis) revealed that maltodextrin was the main contaminant in nine of them, and lactose in two. Raman spectroscopy corroborated these results. Concerning the structure of the CS present in the five CS-rich samples, the ratios 4-sulfated:6-sulfated disaccharides varied from 0.9 to 1.7, and their modal molecular weight was 20–29 kDa. Also, they were all contaminated by small amounts of keratan sulfate (<1%). In conclusion, our findings indicate that the composition of CS preparations not always corresponds to the manufacturers’ descriptions, and indicate that further characterization should be required for the registry and license of pharmaceutical grade CS.

Keywords: Chondroitin sulfate, FACE, Raman spectroscopy, Contaminants, Maltodextrin, Lactose

Da Silva, J. M.; Conegundes, J. L. M.; Mendes, R. F.; Pinto, N. C. C.; Gualberto, A. C. M.; Ribeiro, A.; Gameiro, J.; Aguiar, J. A. K.; Castañon, M. C. M. N.; Scio, E. . Topical Application Of The Hexane Fraction Of L Acistema Pubescens Reduces Skin Inflammation And Cytokine Production In Animal Model. Journal Of Pharmacy And Pharmacology, V. 67, P. 1613-1622, 2015. DOI: 10.1111/jphp.12463 (Arquivo PDF Silva_et_al-2015-Journal_of_Pharmacy_and_Pharmacology)

Abstract

Objectives The aim of this study was to investigate the acute topical anti-inflammatory effect of the hexane fraction (HLP) of Lacistema pubescens in mice. Methods Ear oedema models induced by croton oil, arachidonic acid, phenol, histamine, ethyl phenyl propiolate and capsaicin. Histopathological analyses of eartissue samples sensitized with croton oil were performed. Myeloperoxidase activity (MPO), the pro-inflammatory cytokine-inhibitory effect and dermatoxicity were also evaluated. Key findings HLP (1, 0.5 and 0.1 mg/ear) resulted in a substantial reduction in skin thickness or tissue weight on all models tested, except for capsaicin-induced ear oedema, similar to dexamethasone (0.1 mg/ear) and/or indomethacin (0.5 mg/ear). Histopathological analyses and neutrophil-mediated MPO activity confirmed the topical anti-inflammatory effect of HLP. In addition, HLP reduced IL-1β, IL-6 and tumour necrosis factorα cytokine levels. Sitosterol-rich fraction (SRF), obtained from HLP fractionation, reduced ear oedema on croton oil and phenol models at the same dose of dexamethasone (0.1 mg/ear). No dermotoxicity was observed. Conclusions The mechanism of action of HLP was associated with the inhibition of several pro-inflammatory mediators, including cytokines, arachidonic acid metabolites and histamine, which suggested a glucocorticoid-like effect, reinforced by the presence of the steroid sitosterol. This is the first report on anti-inflammatory activity of L. pubescens leaves.

2014

Peres,G. B. ; Juliano, M. A. ; Aguiar, J. A. K. ; Michelacci, Y M . Streptozotocin-Induced Diabetes Mellitus Affects Lysosomal Enzymes In Rat Liver. Brazilian Journal Of Medical And Biological Research, V. 47, P. 452-460, 2014. http://dx.doi.org/10.1590/1414-431X20143386 (Arquivo PDF1414-431X-bjmbr-1414-431X20143386)

Abstract

It has been previously shown that dextran sulfate administered to diabetic rats accumulates in the liver and kidney, and this could be due to a malfunction of the lysosomal digestive pathway. The aim of the present study was to evaluate the expression and activities of lysosomal enzymes that act upon proteins and sulfated polysaccharides in the livers of diabetic rats. Diabetes mellitus was induced by streptozotocin in 26 male Wistar rats (12 weeks old), while 26 age-matched controls received only vehicle. The livers were removed on either the 10th or the 30th day of the disease, weighed, and used to evaluate the activity, expression, and localization of lysosomal enzymes. A 50-60% decrease in the specific activities of cysteine proteases, especially cathepsin B, was observed in streptozotocin-induced diabetes mellitus. Expression (mRNA) of cathepsins B and L was also decreased on the 10th, but not on the 30th day. Sulfatase decreased 30% on the 30th day, while glycosidases did not vary (or presented a transitory and slight decrease). There were no apparent changes in liver morphology, and immunohistochemistry revealed the presence of cathepsin B in hepatocyte granules. The decrease in sulfatase could be responsible for the dextran sulfate build-up in the diabetic liver, since the action of sulfatase precedes glycosidases in the digestive pathway of sulfated polysaccharides. Our findings suggest that the decreased activities of cathepsins resulted from decreased expression of their genes, and not from general lysosomal failure, because the levels of glycosidases were normal in the diabetic liver.

 – Oliveira, L. G. ; Cunha, A. L. ; Duarte, A. C. ; Castañon, M. C. M. N. ; Chebli, J. M. F. ; Aguiar, J. A. K.  . Positive Correlation Between Disease Activity Index And Matrix Metalloproteinases Activity In A Rat Model Of Colitis. Arquivos de Gastroenterologia (Impresso), V. 51, P. 107-112, 2014. http://dx.doi.org/10.1590/S0004-28032014000200007 (Arquivo PDF 0004-2803-ag-51-02-107)

Abstract

Context: Inflammatory bowel disease, including ulcerative colitis and Crohn’s disease, comprising a broad spectrum of diseases those have in common chronic inflammation of the gastrointestinal tract, histological alterations and an increased activity levels of certain enzymes, such as, metalloproteinases. Objectives: Evaluate a possible correlation of disease activity index with the severity of colonic mucosal damage and increased activity of metalloproteinases in a model of ulcerative colitis induced by dextran sulfate sodium. Methods: Colitis was induced by oral administration of 5% dextran sulfate sodium for seven days in this group (n=10), whereas control group (n=16) received water. Effects were analyzed daily by disease activity index. In the seventh day, animals were euthanized and hematological measurements, histological changes (hematoxylin and eosin and Alcian Blue staining), myeloperoxidase and metalloproteinase activities (MMP-2 and MMP-9) were determined. Results: Dextran sulfate sodium group showed elevated disease activity index and reduced hematological parameters. Induction of colitis caused tissue injury with loss of mucin and increased myeloperoxidase (P<0.001) and MMP-9 activities (45 fold) compared to the control group. Conclusions: In this study, we observed a disease activity index correlation with the degree of histopathological changes after induction of colitis, and this result may be related mainly to the increased activity of MMP-9 and mieloperoxidase.

Key words: Colitis; Crohn disease; Metalloproteinases

 – Guedes, P.L.R. ; Castanon, M. C. M. N. ; Nagaoka, M. R. ; Aguiar, J.A.K. . Increase Of Glycosaminoglycans And Metalloproteinases 2 And 9 In Liver Extracellular Matrix On Early Stages Of Extrahepatic Cholestasis. Arquivos de Gastroenterologia (Impresso), V. 51, P. 309-315, 2014. http://dx.doi.org/10.1590/S0004-28032014000400008 (Arquivo PDF 0004-2803-ag-51-04-309)

Abstract

Context: Cholestasis produces hepatocellular injury, leukocyte infiltration, ductular cells proliferation and fibrosis of liver parenchyma by extracellular matrix replacement. Objective: Analyze bile duct ligation effect upon glycosaminoglycans content and matrix metalloproteinase (MMPs) activities. Methods: Animals (6-8 weeks; n = 40) were euthanized 2, 7 or 14 days after bile duct ligation or Sham-surgery. Disease evolution was analyzed by body and liver weight, seric direct bilirubin, globulins, gamma glutamyl transpeptidase (GGT), alkaline phosphatase (Alk-P), alanine and aspartate aminotransferases (ALT and AST), tissue myeloperoxidase and MMP-9, pro MMP-2 and MMP-2 activities, histopathology and glycosaminoglycans content. Results: Cholestasis caused cellular damage with elevation of globulins, GGT, Alk-P, ALT, AST. There was neutrophil infiltration observed by the increasing of myeloperoxidase activity on 7 (P = 0.0064) and 14 (P = 0.0002) groups which leads to the magnification of tissue injuries. Bile duct ligation increased pro-MMP-2 (P = 0.0667), MMP-2 (P = 0.0003) and MMP-9 (P<0.0001) activities on 14 days indicating matrix remodeling and establishment of inflammatory process. Bile duct ligation animals showed an increasing on dermatan sulfate and/or heparan sulfate content reflecting extracellular matrix production and growing mitosis due to parenchyma depletion. Conclusions: Cholestasis led to many changes on rats’ liver parenchyma, as so as on its extracellular matrix, with major alterations on MMPs activities and glycosaminoglycans content.

Key words: Extrahepatic cholestasis; Glycosaminoglycans; Matrix metalloproteinases

 – Fabri, R. L.; Garcia, R. A.; Florêncio, J. R.; Pinto, N. C. C.  ; Oliveira, L. G. ; Aguiar, J. A. K.; Ribeiro, A. ; Scio, E. . Anti-Inflammatory And Antioxidative Effects Of The Methanolic Extract Of The Aerial Parts Of Mitracarpus Frigidus In Established Animal Models. Journal of Pharmacy and Pharmacology, V. 66, p. 722–732, 2014. DOI: 10.1111/jphp.12189 (Arquivo PDF Fabri_et_al-2014-Journal_of_Pharmacy_and_Pharmacology )

Abstract

Objectives: This study reports the in vivo anti-inflammatory and antioxidative effects of the methanolic extract of the aerial parts of Mitracarpus frigidus (MFM) and its chemical fingerprint. Methods: The acute anti-inflammatory activity was performed using the carrageenan-induced paw oedema and peritonitis, ear oedema induced by croton oil and ethyl phenylpropiolate methods. Total COX, COX-1 and COX-2 expression was also evaluated. Chronic activity was determined by cotton pellet granuloma model. The antioxidative activity was assessed using liver tissue malondialdehyde, catalase and myeloperoxidase activities. Key findings: M. frigidus showed an intense acute anti-inflammatory action (100 and 300 mg/kg) in a nondose-dependent manner with selective inhibition of COX-2 expression. This activity may be also related to the strong antioxidative effect observed. By the other side, the chronic anti-inflammatory activity of MFM was not expressive. Kaempferol, kaempferol-O-rutenoside, rutin, ursolic acid and psychorubrin were identified in MFM. Conclusions: The anti-inflammatory activity of MFM was probably due to inhibition of COX expression in a selective manner for COX-2. Other mechanisms, such as inhibition of inflammatory mediators and of the oxidative stress were possibly involved in the effects observed. To the best of our knowledge, it is the first time those activities are reported for M. frigidus.