ACUTE A SUB-CHRONIC TOXICITY AND IMMUNOMODULATORY ACTIVITY OF AN AQUEOUS EXTRACT OF EUPHORBIA RESINIFERA IN RODENTS

Euphorbia resinifera Berg. (ER) an endemic Moroccan plant has been used to treat different diseases. In spite of its toxicological potential, no scientific report until now was made to evaluate in-vivo neither the toxic effect nor its immunomodulatory activity. The objective was to evaluate the safety of an aqueous extract (AE) of ER in-vivo and its effect on the biochemical, immunological and histopathological parameters. The AE was administrated in single oral dose (5g/kgbw) for the acute toxicity tests given daily by gavages at 0.1, 0.5, 1, 2.5, or 5 g/kg for 28 consecutive days. Serum was analyzed for creatinine, urea, alanine aminotransferase, and aspartate aminotransferase. Histopathological examination of liver, kidneys, and spleen was done at the end of the study. The immunological effect was tested by the evaluation of antibodies production and the level of the delayed type hypersensitivity reaction. No signs of toxicity or deaths were observed in mice treated by a single dose. In the sub-acute toxicity tests, no visible toxic effects were observed at 0.1-1 g/kg doses. However, at 2.5 and 5 g/kg doses, the mice showed some behavioral signs of toxicity. This was confirmed by the histological and biochemical evaluations. When tested against SRBC, there was a significant increase of “haemagglutinating antibody titer” and in “delayed-type hypersensitivity” response in mice treated by ER at 1 g/kg bw (4 and 1.5 times respectively p<0.05). Higher than 2.5 g/kg, the ER can cause liver and kidney toxicity. The immune-stimulatory effect was induced by an inflammatory reaction.