dc.contributor | Leite, Edda Lisboa | |
dc.contributor | | |
dc.contributor | http://lattes.cnpq.br/2279068301048550 | |
dc.contributor | | |
dc.contributor | http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4783254U6&dataRevisao=null | |
dc.contributor | Cruz, Ana Katarina Menezes da | |
dc.contributor | | |
dc.contributor | http://lattes.cnpq.br/9810605697247961 | |
dc.contributor | Farias, Eduardo Henrique Cunha de | |
dc.contributor | | |
dc.contributor | http://lattes.cnpq.br/0933304924768138 | |
dc.contributor | Filgueira, Luciana Guimarães Alves | |
dc.contributor | | |
dc.contributor | http://lattes.cnpq.br/9951316929526841 | |
dc.contributor | Carvalho, Maria Goretti Freire de | |
dc.contributor | | |
dc.contributor | http://lattes.cnpq.br/8934375314306198 | |
dc.creator | Dore, Celina Maria Pinto Guerra | |
dc.date.accessioned | 2013-04-15 | |
dc.date.accessioned | 2014-12-17T14:03:35Z | |
dc.date.accessioned | 2022-10-06T13:07:01Z | |
dc.date.available | 2013-04-15 | |
dc.date.available | 2014-12-17T14:03:35Z | |
dc.date.available | 2022-10-06T13:07:01Z | |
dc.date.created | 2013-04-15 | |
dc.date.created | 2014-12-17T14:03:35Z | |
dc.date.issued | 2012-10-15 | |
dc.identifier | DORE, Celina Maria Pinto Guerra. Aspectos estruturais, farmacológicos e biológicos de fucanas da alga marrom sargassum vulgare. 2012. 112 f. Tese (Doutorado em Bioquímica; Biologia Molecular) - Universidade Federal do Rio Grande do Norte, Natal, 2012. | |
dc.identifier | https://repositorio.ufrn.br/jspui/handle/123456789/12570 | |
dc.identifier.uri | http://repositorioslatinoamericanos.uchile.cl/handle/2250/3964111 | |
dc.description.abstract | The present study examines the chemical composition and their effects on free
radicals, inflammation, angiogenesis, coagulation, VEGF effects and cellular
proliferation of a polysaccharides from alga Sargassum vulgare. The sulfated
polysaccharide was extracted from brown seaweed by proteolysis with enzymes
maxataze. The presence of proteins and sugars were observed in crude
polysaccharides. Fractionation of this crude extract was made with growing
concentration of acetone (0.3-1.5 v) and produced four groups of polysaccharides.
Anionic polysaccharides from brown seaweed Sargassum vulgare, SV1and PSV1
were fractionated (SV1) and purified (PSV1), and displayed with high total sugars
and sulfate content and very low level of protein. This fucan SV1 contains low levels
of protein and high carbohydrate and sulfate content. This polysaccharides prolonged
activated partial thromboplastin time (aPTT) at 50 μg (>240 s). SV1 was found to
have no effect on prothrombin time (PT), corresponding to the extrinsic pathway of
coagulation. SV1 exhibits high antithrombotic action in vivo, with a concentration ten
times higher than heparin. Polysaccharides from S. vulgare promoted direct inhibition
enzymatic activity of thrombin and stimulated enzymatic activity of FXa. SV1 showed
optimal inhibitory activity of thrombin (50.2±0.28%) at a concentration of 25 μg/mL.
Its antioxidant action on scavenging radicals by DPPH was (22%), indicating the
polymer has no cytotoxic action (hemolytic) on ABO and Rh blood types in different
erythrocyte groups and displays strong anti-inflammatory action on all concentrations
tested in the carrageenan-induced paw edema model, demonstrated by reduced
edema and cellular infiltration. Angiogenesis is a dynamic process of proliferation and
differentiation. It requires endothelial proliferation, migration, and tube formation. In
this context, endothelial cells are a preferred target for several studies and therapies.
The antiangiogenic efficacy of polysaccharides was examined in vivo in the chick
chorioallantoic membrane (CAM) model by using fertilized eggs. Decreases in the
density of the capillaries were assessed and scored. The results showed that SV1
and PSV1 have an inhibitory effect on angiogenesis. These results were also
confirmed by inhibition tubulogenesis in rabbit aorta endothelial cell (RAEC) in
matrigel. These compounds were assessed in Apoptosis assay (Annexin V - FITC /
PI) and cell viability by MTT assay of RAEC. These polysaccharides do not affect the
viability and do not have apoptotic or necrotic action. RAEC cell when incubated with
SV1 and PSV1showed inhibition of VEGF secretion, observed when compounds
were incubated at 25, 50 and 100 μg/μL. The VEGF secretion with the RAEC cell line
for 24 h, was more effective for PSV1 at 50 μg/μL(71.4%) than SV1 100 μg/μL
(75.9%). SV1 and PSV1 had an antiproliferative action (47%) against tumor cell line
HeLa. Our results indicate that these sulfated polysaccharides have antiangiogenic
and antitumoral actions | |
dc.publisher | Universidade Federal do Rio Grande do Norte | |
dc.publisher | BR | |
dc.publisher | UFRN | |
dc.publisher | Programa de Pós-Graduação em Bioquímica | |
dc.publisher | Bioquímica; Biologia Molecular | |
dc.rights | Acesso Aberto | |
dc.subject | Alga marrom. Fucana. Hemostasia. Angiogênese | |
dc.subject | Brown seaweed. Fucan. Hemostasis. Angiogenesis | |
dc.title | Aspectos estruturais, farmacológicos e biológicos de fucanas da alga marrom sargassum vulgare | |
dc.type | doctoralThesis | |