Peripheral antinociception and anti-edematogenic effect of a sulfated polysaccharide from Acanthophora muscoides.

BACKGROUND: Sulfated polysaccharides from red marine algae have presented a variety of potentially therapeutic biological effects, however, their antinocicpetive and anti-inflammatory properties are not well understood. METHODS: Male Swiss mice were pretreated with a sulfated polysaccharidic fraction obtained from the marine alga Acanthophora muscoides (AmII) (1, 3 or 9 mg/kg, iv) 30 min prior to either receiving an injection of 0.8% acetic acid or 1% formalin or prior to a thermal stimulus. AmII (1, 3 or 9 mg/kg, sc) was evaluated on carrageenan-, dextran- bradykinin-, histamine- and serotonin-induced rat paw edema models. AmII (500 µg, sc) was also injected into the paw. Additionally, mice were treated with the total sulfated polysaccharides from A. muscoides (Am-TSP) (20 mg/kg, ip) for 14 days. RESULTS: AmII reduced the number of acetic acid-induced writhes and licking time in the second phase of the formalin test, but it did not alter the response latency in the hot plate test, suggesting that its antinociceptive action occurs through a peripheral mechanism. AmII did not reduce carrageenan-induced paw edema and MPO activity. However, it reduced dextran-, histamine- and serotonin-induced paw edemas, but not bradykinin-induced edema, suggesting that histamine is the major target of AmII anti-edematogenic activity. AmII injected into the paw did not evoke local edema. Furthermore, Am-TSP induced no consistent signs of systemic damage, as revealed by body mass, organs wet weight and by biochemical, hematological and histopathological analyses. CONCLUSION: AmII has important antinociceptive and anti-inflammatory properties and represents an important therapeutic agent warranting future studies.

Antinociceptive and anti-inflammatory activities of a sulfated polysaccharide isolated from the green seaweed Caulerpa cupressoides.

BACKGROUND: Red and brown algae sulfated polysaccharides (SPs) have been widely investigated as antinociceptive and/or anti-inflammatory agents; however, no description of these biological properties concerning green algae SPs have been reported. Caulerpa curpressoides (Chlorophyta) presents three SPs fractions (Cc-SP1, Cc-SP2, and Cc-SP3). Anticoagulant (in vitro) and anti- and pro-thrombotic (in vivo) effects of Cc-SP2 had been recently reported. We evaluated the effects of Cc-SP2 using models of nociception and acute inflammation in vivo. METHODS: Male Swiss mice received Cc-SP2 (iv) 30 min prior to receiving 0.6% acetic acid (10 ml/kg, ip), 1% formalin (20 µl, sc) or were subjected to thermal stimuli (51 ± 1 °C). Cc-SP2 was injected sc to male Wistar rats in a peritonitis model or a paw edema model using carrageenan (ip or ipl, 500 µg). To analyze the systemic effects, Cc-SP2 (27 mg/kg, sc) was administrated to both genders mice before waiting for 14 days. RESULTS: Cc-SP2 (3, 9 or 27 mg/kg) reduced (p < 0.05) the number of writhes induced by acetic acid by 57, 89.9 and 90.6%, respectively, the licking time in the first (9 or 27 mg/kg with 42.47 and 52.1%, respectively) and the second (3, 9 or 27 mg/kg with 68.95, 82.34 and 84.61%, respectively) phases. In the hot-plate test, the antinociceptive effect of Cc-SP2 (9 mg/kg) was primarily observed at 60 min (26.7 ± 1.2 s), with its effect reversed by naloxone (8.6 ± 1.3 s), suggesting the involvement of the opioid system. Cc-SP2 (3, 9 or 27 mg/kg, sc, p < 0.05) showed anti-inflammatory effects by decreasing neutrophils migration by 64, 69 and 73%, respectively, and potently reduced the paw edema, especially at the second (0.16 ± 0.02, 0.16 ± 0.03 and 0.12 ± 0.05 ml) and third (0.16 ± 0.03, 0.18 ± 0.02 and 0.14 ± 0.04 ml) hours, respectively. Cc-SP2 did not cause hepatic or renal alterations or affect body mass or the macroscopy of the organs examined (p > 0.05). Histopathological analyses of the liver and kidney showed that both organs were affected by Cc-SP2 treatment, but these effects were considered reversible. CONCLUSION: The results indicate that the analgesic and anti-inflammatory effects of Cc-SP2 could be of biomedical applicability as a new, natural tool in pain and acute inflammatory conditions.

Antinociceptive and anti-inflammatory activities of sulphated polysaccharides from the red seaweed Gracilaria cornea.

Seaweeds have attracted special interest as good sources of sulphated polysaccharides (SP) for use in pharmaceutical industries and biotechnology. In this study, we evaluated the effects of SP from the red seaweed Gracilaria cornea (Gc-TSP) in nociceptive and inflammatory models. In mice, Gc-TSP (3, 9 or 27 mg/kg) significantly reduced nociceptive responses, as measured by the number of writhes, at all tested doses. In a formalin test, Gc-TSP significantly reduced licking time in both phases of the test at a dose of 27 mg/kg. In a hot-plate test, the antinociceptive effect was observed only in animals treated with 27 mg/kg of Gc-TSP, suggesting that the analgesic effect occurs through a central action mechanism at the highest dose. Gc-TSP (3, 9 or 27 mg/kg) caused only a slight reduction in neutrophil migration in the rat peritoneal cavity. However, lower doses of Gc-TSP (3 and 9 mg/kg) significantly inhibited paw oedema induced by carrageenan, especially at 3 hr after treatment. Reduction in oedema was confirmed by myeloperoxidase activity in the affected paw tissue. In addition, treatment (s.c.) of animals with different doses of Gc-TSP inhibited paw oedema induced by dextran within the first hour in all doses tested. After 14 consecutive days of intraperitoneal administration of Gc-TSP (9 mg/kg), we measured the wet weight of the liver, kidney, heart, spleen and thymus and performed biochemical, haematological and histopathological evaluations. No systemic damage was found. These results indicate that Gc-TSP possesses analgesic and anti-inflammatory effects and is a potentially important tool worthy of further study.