title: The renal effects of alginates isolated from brown seaweed Sargassum vulgare.
abstract: Alginates isolated from Sargassum vulgare, present a strong antitumor activity, associated with kidney reversible damage, as analysed by histopathology of treated animals. In the present study, the renal alteration mechanisms of S. vulgare alginates were investigated using the isolated perfused rat kidney and the isolated perfused rat mesenteric blood vessel methods. The results showed that the effects of Sargassum vulgare low viscosity (SVLV) alginate were more potent than those of Sargassum vulgare high viscosity (SVHV) alginate in the isolated rat kidney. The SVLV alginate caused considerable changes in renal physiology, as shown by an increase in parameters such as perfusion pressure, renal vascular resistance, glomerular filtration rate, urinary flow and sodium, potassium and chloride excretion and by reduction of chloride tubular transport. The effects of SVHV were weaker than those of SVLV. The effects of SVLV on kidney could be related to direct vascular action as demonstrated with SVLV alginate on mesenteric blood vessels. In conclusion, the Sargassum vulgare alginate altered the renal function parameters evaluated. S. vulgare low viscosity alginate renal effects were more potent than S. vulgare high viscosity alginate. It is suggested that physicochemical differences between SVHV and SVLV could explain the differences found in the results.
authors.affiliation: Departamento de Fisiologia e Farmacologia, Faculdade de Medicina, Universidade Federal do Ceará, P.O. Box-3157, 60430-270, Fortaleza, Ceará, Brasil.
authors.forename: Alessandra
authors.initials: A
authors.lastname: de Paula Alves Sousa
authors.forename: Paulo Sergio Ferreira
authors.initials: PS
authors.lastname: Barbosa
authors.forename: Márcia Rocha
authors.initials: MR
authors.lastname: Torres
authors.forename: Alice Maria Costa
authors.initials: AM
authors.lastname: Martins
authors.forename: René Duarte
authors.initials: RD
authors.lastname: Martins
authors.forename: Renata
authors.initials: R
authors.lastname: de Sousa Alves
authors.forename: Daniel Freire
authors.initials: DF
authors.lastname: de Sousa
authors.forename: Claudênio Diógenes
authors.initials: CD
authors.lastname: Alves
authors.forename: Letícia Veras
authors.initials: LV
authors.lastname: Costa-Lotufo
authors.forename: Helena Serra Azul
authors.initials: HS
authors.lastname: Monteiro
mesh_terms: D000284:Administration, Oral; D000464:Alginates / Q000737:chemistry / Q000633:toxicity*; D000818:Animals; D066298:In Vitro Techniques; D007668:Kidney / Q000187:drug effects* / Q000378:metabolism / Q000503:physiopathology; D007677:Kidney Function Tests; D010477:Perfusion; D010936:Plant Extracts / Q000633:toxicity; D051381:Rats; D017208:Rats, Wistar; D044647:Sargassum / Q000737:chemistry*; D013152:Splanchnic Circulation / Q000187:drug effects / Q000502:physiology; D014783:Viscosity
chemical_list: D000464:Alginates; D010936:Plant Extracts