Effect of a soluble α- d-glucan from the lichenized fungus Ramalina celastri on macrophage activity

• Published in: International immunopharmacology Vol. 2; no. 5; pp. 691 - 698
• Main Authors: Stuelp-Campelo, Patrı́cia Ma, de Oliveira, Maria Benigna M, Leão, Ana M.A.C, Carbonero, Elaine R, Gorin, Philip A.J, Iacomini, Marcello
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01-04-2002; Elsevier
• Subjects: Animals; Antineoplastic agents; Ascomycota - chemistry; Biological and medical sciences; Chemotherapy; Female; glucans; Glucans - chemistry; Glucans - isolation & purification; Glucans - pharmacology; Glucans - therapeutic use; Hydrogen peroxide; Lichens - chemistry; Lichens - isolation & purification; Macrophage; Macrophages - drug effects; Macrophages - immunology; Macrophages - metabolism; Medical sciences; Mice; Phagocytosis; Pharmacology. Drug treatments; Plant Extracts - chemistry; Plant Extracts - isolation & purification; Plant Extracts - pharmacology; Plant Extracts - therapeutic use; polysaccharides; Ramalina celastri; Sarcoma 180 - drug therapy; Sarcoma 180 - metabolism; Sarcoma-180 cells; Solubility; α-Glucan; PBS; α-Glucan; Hydrogen peroxide; PMA; Sarcoma-180 cells; HBSS; Phagocytosis; VTM; Macrophage; PEC; Antineoplastic agent; Intraperitoneal administration; Sarcoma; Immunomodulation; Rodentia; Extract; Malignant tumor; Soluble form; Fungi; Glucan; Vertebrata; Chemotherapy; Mammalia; Treatment; Mouse; Animal; Lichenes; Mechanism of action; Thallophyta
• ISSN: 1567-5769; 1878-1705
• DOI: 10.1016/S1567-5769(02)00003-6

An α-glucan from the lichen
Ramalina celastri has previously been demonstrated to have cytotoxic effects against HeLa cells. This polysaccharide was studied using Sarcoma-180 cells as tumoral model, and its effects on peritoneal exudate cells, namely, hydrogen peroxide production, phagocytic activity and cell eliciting activity are evaluated. Tumors developing in animals treated with the glucan at a dose of 200 mg kg
−1, had a tumor size ∼80% smaller than that of the control group, showing an impairment of tumor establishment. The polysaccharide was injected into mice not bearing a tumor and after 7, 15 and 30 days the cells were collected from the peritonea. The number of peritoneal cells increased ∼130% 7 days after inoculation, and then gradually decreased. Hydrogen peroxide production was 75% greater 7 and 15 days after inoculation, on in vitro phorbol myristate acetate (PMA) triggering. Without PMA, the difference in hydrogen peroxide production was not significant. Phagocytic assays using fluorescent beads showed that the uptake increased 7 and 15 days after inoculation, when compared with the control. These results thus suggest a possible role of the
R. celastri glucan as a biological response modifier (BRM).