Navegando por Autor "Almeida-Lima, Jailma"

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Heterofucan from Sargassum filipendula induces apoptosis in HeLa cells
(MDPI, 2011-04-14) Costa, Leandro Silva; Telles, Cinthia Beatrice Silva; Oliveira, Ruth Medeiros; Nobre, Leonardo Thiago Duarte Barreto; Dantas-Santos, Nednaldo; Câmara, Rafael Barros Gomes da; Costa, Mariana Santana Santos Pereira; Almeida-Lima, Jailma; Melo-Silveira, Raniere Fagundes; Albuquerque, Ivan Rui Lopes; Leite, Edda Lisboa; Rocha, Hugo Alexandre de Oliveira
Fucan is a term used to denominate a family of sulfated polysaccharides rich in sulfated L-fucose. Heterofucan SF-1.5v was extracted from the brown seaweed Sargassum filipendula by proteolytic digestion followed by sequential acetone precipitation. This fucan showed antiproliferative activity on Hela cells and induced apoptosis. However, SF-1.5v was not able to activate caspases. Moreover, SF-1.5v induced glycogen synthase kinase (GSK) activation, but this protein is not involved in the heterofucan SF-1.5v induced apoptosis mechanism. In addition, ERK, p38, p53, pAKT and NFκB were not affected by the presence of SF-1.5v. We determined that SF-1.5v induces apoptosis in HeLa mainly by mitochondrial release of apoptosis-inducing factor (AIF) into cytosol. In addition, SF-1.5v decreases the expression of anti-apoptotic protein Bcl-2 and increased expression of apoptogenic protein Bax. These results are significant in that they provide a mechanistic framework for further exploring the use of SF-1.5v as a novel chemotherapeutics against human cervical cancer
In vitro studies reveal antiurolithic effect of antioxidant sulfated polysaccharides from the green seaweed Caulerpa cupressoides var flabellata
(MDPI, 2019-06-01) Gomes, Dayanne Lopes; Melo, Karoline Rachel Teodosio; Queiroz, Moacir Fernandes; Batista, Lucas Alighieri Neves Costa; Santos, Pablo Castro; Costa, Mariana Santana Santos Pereira; Almeida-Lima, Jailma; Câmara, Rafael Barros Gomes da; Costa, Leandro Silva; Rocha, Hugo Alexandre de Oliveira
Urolithiasis affects approximately 10% of the world population and is strongly associated with calcium oxalate (CaOx) crystals. Currently, there is no efficient compound that can be used to prevent this disease. However, seaweeds’ sulfated polysaccharides (SPs) can change the CaOx crystals surface’s charge and thus modify the crystallization dynamics, due to the interaction of the negative charges of these polymers with the crystal surface during their synthesis. We observed that the SPs of Caulerpa cupressoides modified the morphology, size and surface charge of CaOx crystals. Thus, these crystals became similar to those found in healthy persons. In the presence of SPs, dihydrate CaOx crystals showed rounded or dumbbell morphology. Infrared analysis, fluorescence microscopy, flow cytometry (FITC-conjugated SPs) and atomic composition analysis (EDS) allowed us to propose the mode of action between the Caulerpa’s SPs and the CaOx crystals. This study is the first step in understanding the interactions between SPs, which are promising molecules for the treatment of urolithiasis, and CaOx crystals, which are the main cause of kidney stones
In Vivo evaluation of the antioxidant activity and protective action of the seaweed Gracilaria birdiae
(Hindawi, 2018-08-01) Barros-Gomes, Joanna Angelis Costa; Nascimento, Daiany Laise Araújo; Silveira, Ana Cristina Rodrigues; Silva, Rayanne Kelly; Gomes, Dayane Lopes; Melo, Karoline Rachel Teodosio; Almeida-Lima, Jailma; Câmara, Rafael Barros Gomes da; Silva, Naisandra Bezerra; Rocha, Hugo Alexandre de Oliveira
The red seaweed Gracilaria birdiae (GB) is farmed and used as food in northeast Brazil. However, the economic potential of this seaweed has been explored little. To enable direct consumption and/or product diversification from GB, it is necessary to evaluate its effect in vivo. In this study, the food of mice was improved with the addition of GB. After 21 days, the consumption of seaweed reduced the weight gain and blood glucose levels in mice. In addition, it increased the trolox equivalent antioxidant capacity and glutathione reductase and catalase levels compared to those of the control group. In addition, some mice also received carbon tetrachloride (CCl4). In this case, histological, enzymatic, and antioxidant tests showed that the seaweed could protect animals from damage caused by this toxic agent. In addition, GB aqueous extract (AE) inhibited 50% of 3T3-L1 cell differentiation into adipocytes, whereas GB ethanolic extract was not effective. AE is composed mainly of sulfated polysaccharides. The results of the present study indicate that the alga GB protected the mice from CCl4-induced damage, indicating that the seaweed exhibits protective action in vivo. In addition, GB decreased the animal weight gain, which was mainly due to the action of the sulfated polysaccharides synthesized by this seaweed
A low-molecular-weight galactofucan from the seaweed, Spatoglossum schröederi, binds fibronectin and inhibits capillary-like tube formation in vitro
(Elsevier, 2018-05) Menezes, Maira Maria; Nobre, Leonardo Thiago Duarte Barreto; Rossi, Gustavo Rodrigues; Almeida-Lima, Jailma; Melo-Silveira, Raniere Fagundes; Franco, Celia Regina Cavichiolo; Trindade, Edvaldo Silva; Nader, Helena Bonciani; Rocha, Hugo Alexandre de Oliveira
A low-molecular-weight (LMW) heterofucan (designated fucan B) was obtained from the brown seaweed, Spatoglossum schröederi, and its activity as an inhibitor of capillary-like tube formation by endothelial cells (ECs) was analyzed. Chemical, infrared and electrophoretic analyses confirmed the identity of fucan B. In contrast to other LMW fucans, fucan B (0.012–0.1 mg/mL) inhibited ECs capillary-like tube formation in a concentrationdependent manner. In addition, fucan B (0.01–0.05 mg/mL) did not affect ECs proliferation. Fucan B also inhibited ECs migration on a fibronectin-coated surface, but not on laminin- or collagen-coated surfaces. Biotinylated fucan B was used as a probe to identify its localization. Confocal microscopy experiments revealed that biotinylated fucan did not bind to the cell surface, but rather only to fibronectin. Our findings suggest that fucan B inhibits ECs capillary-like tube formation and migration by binding directly to fibronectin and blocking fibronectin sites recognized by cell surface ligands. However, further studies are needed to evaluate the in vivo effects of fucan B

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Navegando por Autor "Almeida-Lima, Jailma"