Polissacarídeo sulfatado extraído da alga gracilaria domingensis: atividade anti-inflamatória e antinociceptiva

Abstract

Marine algae are natural sources of sulfated polysaccharides (PLS), extracellular matrix biopolymers that have pharmacological properties. PLSs from red algae of the genus Gracilaria have biological actions capable of attenuating components of the inflammatory process including edema, cytokines, cell migration and pain. For this reason, these

bioproducts found in regional biodiversity constitute an alternative to the conventional anti- inflammatory therapeutic approach. Thus, the present study aimed to evaluate the anti- inflammatory and antinociceptive potential of PLS extracted from the Gracilaria domingensis

species in an animal model. Initially, the seaweed was collected and the PLS extracted with subsequent registration in the genetic heritage with the number A00BA4D. The work was also approved by the Committee on Ethics in Animal Use (CEUA) under number 480/018. Subsequently, pharmacological studies were carried out in female Swiss mice (25-30 g), divided into groups of 6 animals. The animals were treated with G. domingensis PLS at doses of 2.5; 5 or 10 mg/Kg intraperitoneally and subjected to carrageenan edema in order to obtain the best dose with an anti-inflammatory effect. Then, histamine, serotonin, bradykinin, prostaglandin E2 (PGE2) and compound 48/80 edemas were induced, as well as peritonitis in mice and the peritoneal fluid was evaluated for leukocyte migration, measurement of myeloperoxidase activity (MPO) and glutathione (GSH) and malondialdehyde (MDA) levels. The animals were also submitted to nociceptive tests by chemical agents (0.6% acetic acid and 2.5% formalin). As results obtained, the dose of 10 mg/kg demonstrated a significant reduction (p<0.05) of the paw edema induced by carrageenan in relation to the other tested doses, as well as significantly attenuated (p<0.05) edema from the inflammatory agents histamine, serotonin, bradykinin, PGE2, compound 48/80. In addition, PLS showed the ability to significantly decrease (p<0.05) leukocyte migration, MPO and MDA levels, and preserved GSH levels in the peritoneal exudate of animals that suffered peritonitis. The best dose of PLS showed antinociceptive action in the abdominal writhing test and in the formalin test. Thus, the results obtained allow us to infer that PLS extracted from G. domingensis at a dose of 10 mg/kg has an anti-inflammatory and antinociceptive effect.