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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Extra??o, caracteriza??o e prospec??o de atividades farmacol?gicas de polissacar?deos sulfatados da macroalga verde Caulerpa prolifera

C?mara, Rafael Barros Gomes da 20 August 2015 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-05-31T00:26:34Z No. of bitstreams: 1 RafaelBarrosGomesDaCamara_TESE.pdf: 5185586 bytes, checksum: ac9f52b2d0105b2f8e729ae0d148ebaa (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-06-02T23:03:58Z (GMT) No. of bitstreams: 1 RafaelBarrosGomesDaCamara_TESE.pdf: 5185586 bytes, checksum: ac9f52b2d0105b2f8e729ae0d148ebaa (MD5) / Made available in DSpace on 2016-06-02T23:03:58Z (GMT). No. of bitstreams: 1 RafaelBarrosGomesDaCamara_TESE.pdf: 5185586 bytes, checksum: ac9f52b2d0105b2f8e729ae0d148ebaa (MD5) Previous issue date: 2015-08-20 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / O presente estudo teve como objetivo extrair, caracterizar e realizar uma an?lise prospectiva de atividades farmacol?gicas de polissacar?deos sulfatados da macroalga verde Caulerpa prolifera. Sete fra??es (CP-0.3/CP-0.5/CP-0.7/CP-0.9/CP-1.1/CP-1.5/CP-2.0) foram obtidas de C. prolifera por prote?lise alcalina seguida de precipita??o sequencial em acetona. As an?lises f?sico-qu?micas indicaram que C. prolifera sintetiza diferentes popula??es de heteropolissacar?deos sulfatados. Na an?lise da atividade anticoagulante, todas as fra??es, exceto CP-0.3, apresentaram influ?ncia sobre a via intr?nseca da coagula??o. Todas as fra??es apresentaram atividade antioxidante em 6 ensaios diferentes, sendo mais pronunciadas no teste de sequestro de per?xido de hidrog?nio, com destaque para CP-0.3, CP-0.7 e CP-0.9 (quando se obteve at? 61% de sequestro), no teste de quela??o f?rrica (com destaque para CP-0.9, com 56% de quela??o) e no teste de quela??o c?prica (com destaque para CP-2.0, com quela??o de 78%). Com rela??o a a??o imunomoduladora, a presen?a de CP-0.3, CP-0.7 e CP-0.9 promoveu aumento da produ??o de ?xido n?trico (ON) em macr?fagos em at? 48, 142 e 163 vezes, respectivamente. De maneira oposta, a s?ntese de ON caiu em 73% quando macr?fagos ativados por LPS foram incubados concomitantemente com CP-2. A atividade anti-adipog?nica das fra??es tamb?m foi avaliada e o destaque ficou com CP-1.5, na presen?a desta fra??o (0,2 mg/mL) a diferencia??o de pr?-adip?citos (3T3-L1) em adip?citos foi reduzida em 60%. Vale salientar, que a viabilidade das c?lulas 3T3-L1 n?o foi afetada pela presen?a de CP-1.5. O que n?o ocorreu com c?lulas de c?ncer cervical humano (HeLa) e de adenocarcinoma renal humano (786-0), j? que a viabilidade dessas c?lulas caiu quando elas foram expostas as fra??es, o destaque foi para a redu??o da viabilidade em torno de 55% quando as c?lulas HeLa foram incubadas com CP-0.3, CP-0.5 e CP-0.9. J? com 786-0, o melhor resultado encontrado foi com o uso da fra??o CP-1.5, quando se obteve uma redu??o de ~75% da viabilidade celular. N?o se identificou atividade leishmanicida ou microbicida contra a Klebsiella pneumoniae Carbapenemase (KPC) com ao se testar as fra??es contra estes organismos. No entanto, a prolifera??o de Staphylococcus epidermidis foi diminu?da em 30% na presen?a de CP-1.5. Outro resultado relevante, foi a observa??o de que a forma??o de cristais de oxalato c?lcio na presen?a das fra??es era alterada. Destaca-se CP-0.3, CP-0.5 e CP-1.1, j? que na presen?a dessas fra??es identificou-se apenas a forma??o de cristais dihidratados e de tamanho m?dio 80% menor do que aquele verificado no grupo controle. Dados oriundos da avalia??o do potencial zeta dos cristais formados na presen?a das fra??es e da avalia??o de imagens de microscopia confocal de cristais formados na presen?a das fra??es marcadas fluorescentemente levaram a hip?tese de que os polissacar?deos presentes nas fra??es interagem com o c?lcio da rede cristalina e isso afeta o crescimento e a morfologia dos cristais formados. Os resultados aqui descritos levam a sugest?o de os principais agentes respons?veis pelas atividades observadas com as fra??es seriam os polissacar?deos sulfatados, portanto passos posteriores de purifica??o desses pol?meros, bem como a investiga??o de seus mecanismos de a??o devem ser investigados. Por fim, os dados aqui obtidos levam a observa??o de que as fra??es ricas em polissacar?deos obtidas da alga C. prolifera apresentam um potencial multiterap?utico por serem anticoagulantes, antioxidantes, imunomoduladores, citot?xicas contra c?lulas tumorais, anti-adipogenicos, antibacterianas e alterarem a forma??o de cristais de oxalato de c?lcio. / This study aimed to extract, characterize and conduct a prospective analysis of pharmacological activities of sulfated polysaccharides from green seaweed Caulerpa prolifera. Seven fractions (CP-0.3/CP-0.5/CP-0.7/CP-0.9/CP-1.1/CP-1.5/CP-2.0) were obtained from C. prolifera by alkaline proteolysis followed by sequential precipitation in acetone. The physicochemical analyzes indicated that C. prolifera synthesizes a homogalactan (CP-0.9) and different populations of sulfated heteropolysaccharides. In the analysis of anticoagulant activity, all fractions except CP-0.3, influenced the intrinsic coagulation pathway. All fractions showed antioxidant activity in six different assays being more pronounced in hydrogen peroxide scavenging assay, especially CP-0.3, CP-0.7 and CP-0.9 (which obtained 61% of hydrogen peroxide scavenging), in ferric chelation assay (especially CP-0.9 with 56% chelation) and cupric chelation assay (especially CP-2.0 with 78% chelation). With respect to immunomodulatory activity, the presence of CP-0.3, CP-0.7 and CP-0.9 showed an immunogenic potential, increasing the production of nitric oxide (NO) by 48, 142 and 163 times, respectively. Conversely, the NO synthesis fell 73% after the activation of macrophages by LPS, incubated concurrently with CP-2.0. The anti-adipogenic activity of the fractions was also evaluated and CP-1.5 was able to reduce the differentiation of pre-adipocytes (3T3-L1) into adipocytes by 60%, without affecting the cell viability. The fractions CP-0.3, CP-0.5 and CP-0.9 reduced the viability of the HeLa cells (human cervical adenocarcinoma) by 55% and CP-1.5 reduced the viability of the 786-0 cells (human renal adenocarcinoma) by 75%. Leishmanicidal activity and microbicide effect against Carbapenem-resistant Klebsiella pneumoniae (KPC) have not been identified. However, the viability of Staphylococcus epidermidis was reduced by 23.8% in the presence of CP -1.5. All fractions were able to change the formation of calcium oxalate crystals. CP-0.3, CP-0.5 and CP-1.1 only promoted the formation of COD type crystals with a very small size (1 ?m). Confocal microscopy and zeta potential data of crystals formed in the presence of the samples showed that the polysaccharides present in the fractions must interact with calcium ions present throughout the crystal lattice, affecting the growth and morphology of crystals The results described herein indicate that the fractions rich in polysaccharides obtained from the green seaweed C. prolifera present a multi therapeutic potential, and subsequent purification steps, as well as research on the mechanisms of action by which these polymers act should be investigated.

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