Antinociceptive and anti-inflammatory activities of Sargassum wightii and Halophila ovalis sulfated polysaccharides in experimental animal models.

The present study investigated the effects of sulfated polysaccharides from brown seaweed Sargassum wightii (Sw-SP) and seagrass Halophila ovalis (Ho-SP) in nociceptive and inflammatory models. In the formalin test, Sw-SP and Ho-SP significantly reduced licking time in both phases of the test at a dose of 10 mg/kg. In the hot plate test, the antinociceptive effect was observed only in animals treated with 10 mg/kg of Sw-SP and 5, 10 mg/kg of Ho-SP, suggesting that the analgesic effect occurs through a central action mechanism at the higher dose. Sw-SP and Ho-SP (10 mg/kg) significantly inhibited paw edema induced by carrageenan, especially at 3 h after treatment and potentially decreased neutrophil migration by 53% and 52%, respectively. In Freund's adjuvant-induced arthritic rats, there was a significant increase in the rat paw volume and decrease in body weight, but in Sw-SP- and Ho-SP-treated groups (10 mg/kg), a significant reduction in paw volume and a normal gain in body weight were observed. The present results indicate that Sw-SP and Ho-SP possess antinociceptive and anti-inflammatory effects and have potential usefulness for development as therapeutic agents.