Navegando por Autor "Melo, Karoline Rachel Teodosio"
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Artigo Antioxidant sulfated polysaccharide from edible red seaweed Gracilaria birdiae is an inhibitor of calcium oxalate crystal formation(MDPI, 2020-04-28) Oliveira, Leticia Castelo Branco Peroba; Queiroz, Moacir Fernandes; Fidelis, Gabriel Pereira; Melo, Karoline Rachel Teodosio; Câmara, Rafael Barros Gomes da; Alves, Monique Gabriela das Chagas Faustino; Costa, Leandro Silva; Teixeira, Dárlio Inácio Alves; Melo-Silveira, Raniere Fagundes; Rocha, Hugo Alexandre de OliveiraThe genus Gracilaria synthesizes sulfated polysaccharides (SPs). Many of these SPs, including those synthesized by the edible seaweed Gracilaria birdiae, have not yet been adequately investigated for their use as potential pharmaceutical compounds. Previous studies have demonstrated the immunomodulatory effects of sulfated galactans from G. birdiae. In this study, a galactan (GB) was extracted from G. birdiae and evaluated by cell proliferation and antioxidant tests. GB showed no radical hydroxyl (OH) and superoxide (O2−) scavenging ability. However, GB was able to donate electrons in two further different assays and presented iron- and copper-chelating activity. Urolithiasis affects approximately 10% of the world’s population and is strongly associated with calcium oxalate (CaOx) crystals. No efficient compound is currently available for the treatment of this disease. GB appeared to interact with and stabilize calcium oxalate dihydrate crystals, leading to the modification of their morphology, size, and surface charge. These crystals then acquired the same characteristics as those found in healthy individuals. In addition, GB showed no cytotoxic effect against human kidney cells (HEK-293). Taken together, our current findings highlight the potential application of GB as an antiurolithic agentArtigo Commercial fucoidans from Fucus vesiculosus can be grouped into antiadipogenic and adipogenic agents(MDPI, 2018-06-04) Oliveira, Ruth Medeiros; Câmara, Rafael Barros Gomes da; Monte, Jessyka Fernanda Santiago; Viana, Rony Lucas Silva; Melo, Karoline Rachel Teodosio; Queiroz, Moacir Fernandes; Filgueira, Luciana Guimarães Alves; Oyama, Lila Missae; Rocha, Hugo Alexandre de OliveiraFucus vesiculosus is a brown seaweed used in the treatment of obesity. This seaweed synthesizes various bioactive molecules, one of them being a sulfated polysaccharide known as fucoidan (FF). This polymer can easily be found commercially, and has antiadipogenic and lipolytic activity. Using differential precipitation with acetone, we obtained four fucoidan-rich fractions (F0.5/F0.9/F1.1/F2.0) from FF. These fractions contain different proportions of fucose:glucuronic acid:galactose:xylose:sulfate, and also showed different electrophoretic mobility and antioxidant activity. Using 3T3-L1 adipocytes, we found that all samples had lipolytic action, especially F2.0, which tripled the amount of glycerol in the cellular medium. Moreover, we observed that FF, F1.0, and F2.0 have antiadipogenic activity, as they inhibited the oil red staining by cells at 40%, 40%, and 50%, respectively. In addition, they decreased the expression of key proteins of adipogenic differentiation (C/EBPα, C/EBPβ, and PPARγ). However, F0.5 and F0.9 stimulated the oil red staining at 80% and increased the expression of these proteins. Therefore, these fucoidan fractions have an adipogenic effect. Overall, the data show that F2.0 has great potential to be used as an agent against obesity as it displays better antioxidant, lipolytic and antiadipogenic activities than the other fucoidan fractions that we testedArtigo 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 OliveiraUrolithiasis 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 stonesArtigo 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 OliveiraThe 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