Effect of Pterodon pubescens seeds Oil (PpO) and its hexanic fraction on humoral and cellular immune response in mice.
Rêgo,G.C.G.; Silva, T.F.; Pinto, A.C.; Sabino, K.C.C.; Coelho, M.G.P.
Biochemistry Department, University of Rio de Janeiro State, Rio de Janeiro, Brazil.
We have previously demonstrated an anti-arthritic effect for PpO using collagen induced arthritis (CIA) model in mice. CIA is characterized by inflammatory reaction in the joints and increased cellular and humoral immune response. The aim of this work is to monitor the in vivo immunomodulatory effects of PpO on its hexanic fraction (HF). We studied the antibody production and delayed type hypersensitivity (DTH) to sheep red blood cells (SRBC). Female SW mice were separated into eleven groups of 8 each: treated with 0.5%Tween 20 in 15% ethanol (vehicle), dexamethasone 5 mg/kg (dexa), PpO 0.1 mg, 1 mg, 10 mg, and 100 mg/kg b.w. and HF 0.1 mg, 1 mg, 10 mg, 100 mg and 1 mg/kg b.w.. Mice were orally and daily treated (50 mL) during 7 days. For antibody production the animals were immunized intraperitoneally with 2.5 x 108 SRBC on day 1 and sacrificed on day 8. IgM anti-SRBC was evaluated by hemagglutination titer using 0.5% SRBC final concentration. The anti-SRBC antibody titer was determined as the highest serum dilution causing visible hemagglutination. Delayed type hypersensitivity (DTH) was induced with subcutaneous (s.c) immunization in the neck with 1 x 108 SRBC/0.2ml in sterile saline on day 2 and challenged (1 x 108 SRBC/0.05ml, s.c.) in left hind paw on day 7. The paw edema was determinated by plethysmography on day 8. After anesthesia, the animals were bled and the sera obtained. SRBC immunized animals treated with vehicle presented serum anti-SRBC titer of 537±188 while the treatment with PpO 1, 10 and 100 mg/kg b.w. reduced (p<0.05) to 224±64, 325±155, 281±140, respectively. DTH response of animals treated with vehicle presented edema index of 54±14% while the treatment with PpO 0.1 and 1 mg/kg b.w. reduced (p<0.05) to 36±9 and 35±9, respectively. When PpO was fractioned, the HF did not induce suppressive effect on cellular or humoral immune response. Suppressive positive control (dexamethasone) showed anti-SRBC titer of 144±80 and paw edema index of 9±4%. PpO showed in vivo immunosuppressive effects in mice but one of its fractions, the hexânica one did not induce inhibition on humoral or cellular immune response. Supported by: UERJ, FAPERJ.
|