Evaluation of avocado/soybean unsaponifiable alone or concurrently with praziquantel in murine schistosomiasis

Aiming to study the influence of administration of avocado/soybean unsaponifiable (ASU) alone or concurrently with praziquantel (PZQ) on Schistosoma mansoni-infected mice, this study was established. ASU (300 mg/kg) was administered orally at 3 time intervals; 30 days prior to infection, 1 day post-infection (pi), 3 weeks pi and continued until week 7 pi. All the mice were sacrificed 9 weeks pi. Administration of ASU either prior to the infection or 1 day pi resulted in significant elimination of 30.2% and 19.1% of the recovered worms, respectively, and caused mild, to moderate surface, ultrastructure damage in some worms. The reduction in worm burden was proportional to the number of coupled worms, indicating a possible uncoupling nature of ASU. ASU significantly decreased the number of eggs/g of the liver and altered oogram pattern in both infected and PZQ-treated groups. The time and duration of ASU administration clearly affected the worm and egg loads. ASU significantly reduced granuloma sizes, and the levels of the cytokines, interferon-gamma (IFN-γ) and interleukin-4 (IL-4), in both infected and PZQ-treated groups indicating its anti-inflammatory activity. Taken together, these findings suggest that long term administration of ASU may result in a mild course of murine schistosomiasis and may be a promising complementary treatment to PZQ.