Evaluation of the antischistosomal activity of sulfated α-D-glucan from the lichen Ramalina celastri free and encapsulated into liposomes

• Published in: Brazilian journal of medical and biological research Vol. 44; no. 4; pp. 311 - 318
• Main Authors: Araújo, R V S, Melo-Júnior, M R, Beltrão, E I C, Mello, L A, Iacomini, M, Carneiro-Leão, A M A, Carvalho, Jr, L B, Santos-Magalhães, N S
• Format: Journal Article
• Language: English
• Published: Brazil Associação Brasileira de Divulgação Científica 01-04-2011
• Subjects: Animals; Anthelmintics - administration & dosage; Anthelmintics - pharmacology; BIOLOGY; Feces - parasitology; Female; Glucans - administration & dosage; Glucans - isolation & purification; Glucans - pharmacology; Immunohistochemistry; Intestines - parasitology; Intestines - pathology; Lectin histochemistry; Lichens - chemistry; Liposomes; Liver - parasitology; Liver - pathology; Male; MEDICINE, RESEARCH & EXPERIMENTAL; Mice; Plant Extracts - administration & dosage; Plant Extracts - pharmacology; Polysaccharide; Ramalina celastri; Schistosoma mansoni; Schistosoma mansoni - drug effects; Schistosomiasis mansoni - drug therapy; α-D-glucan; Schistosoma mansoni; Lectin histochemistry; α-D-glucan; Ramalina celastri; Liposomes; Polysaccharide
• ISSN: 1414-431X; 0100-879X; 1414-431X
• DOI: 10.1590/s0100-879x2011000400007

The antischistosomal activity of the sulfated polysaccharide α-D-glucan (Glu.SO(4)) extracted from Ramalina celastri was evaluated after encapsulation into liposomes (Glu.SO(4)-LIPO) in Schistosoma mansoni-infected mice. The effect of treatment with Glu.SO(4) and Glu.SO(4)-LIPO (10 mg/kg) on egg elimination, worm burden and hepatic granuloma formation was assessed using female albino Swiss mice, 35-40 days of age, weighing 25 ± 2 g, infected with 150 cercariae/animal (Biomphalaria glabrata, BH strain). Four groups (N = 10) were studied, two controls (empty liposomes and NaCl) and two treated groups (Glu.SO(4)-LIPO and Glu.SO(4)) using a single dose. Parasitological analysis revealed that Glu.SO(4)-LIPO was as efficient as Glu.SO(4) in reducing egg elimination and worm burden. Treatment with free Glu.SO(4) and Glu.SO(4)-LIPO induced a statistically significant reduction in the number of granulomas (62 and 63%, respectively). Lectin histochemistry showed that wheat germ agglutinin intensely stained the egg-granuloma system in all treated groups. On the other hand, peanut agglutinin stained cells in the control groups, but not in the treated groups. The present results suggest a correlation between the decreasing number of hepatic egg-granulomas and the glycosylation profile of the egg-granuloma system in animals treated with free Glu.SO(4) or Glu.SO(4)-LIPO.