It was investigated the effect of hydroalcoholic extract (HEP) of propolis from Scaptotrigona aff. postica on the solid Ehrlich tumor, on the tumor-bearing mice lymphoid organs and on the nitric oxide (NO) production. Swiss mice were divided in 4 groups: control, HEP 0.5; HEP 5 and HEP 50 that was treated by intraperitoneal route with a single dose of saline solution (NaCl 0.9%) or 0.5 or 5 or 50 mg of HEP/kg body weight, respectively. After 48 h of treatment, the animals were inoculated with 10(5) tumor cells in their footpad. The results showed that the treatment with HEP in the doses of 5 and 50 mg/kg inhibited the development of the tumor from the 6th day post inoculums when compared to the control and to the HEP 0.5 groups. Besides, there was an increase of spleen and bone marrow cell number in HEP 0.5 and HEP 5 as compared to the control. Concanavalin A (ConA)-stimulated NO production was decreased in all HEP-treated groups when compared to the control. In conclusion, the treatment with HEP had an anti-tumor effect what may be related to its chemical composition and to the inhibition of NO production.
propolis; Scaptotrigona aff. postica; Ehrlich tumor; stingless bee; Meliponinae