An adjuvant effect of Metformin as an anti-fibrotic agent when administered with the anti-schistosomal Praziquantel in Schistosoma mansoni infected mice

Schistosomiasis is the second most common parasitic disease post Malaria around the world. Praziquantel (PZQ) is known as the most efficient anti- schistosomal drug but has no anti-fibrotic effect. Metformin (Met) is a well-known drug for type 2 diabetes. This study aimed to evaluate the role of Met as anti-schistosomal and anti-fibrotic agents alone or in combination with PZQ treatment. Forty male CD1 mice were divided into four groups (n=10 mice) as following; the first group (Gp1) was served as a negative control. Gp2, Gp3, Gp4, and GpS were infected with (60-80) S. mansoni cercariae. After a month of infection, Gp3 was administered orally with PZQ (500 mg/Kg) for 2 consecutive days. Gp4 was administered orally with Met (150 mg/Kg) for 15 consecutive days, and GpS was orally administered with PZQ followed by Met for 15 consecutive days at the same doses as in Gp 3 and 4. The results showed that PZQ had potent worms and egg reduction in liver and intestine tissues with no anti-fibrotic effect of the granuloma formation. However, Met or PZQ/Met treatment post-infection led to a reduction in egg count in both liver and intestine tissues with a significant reduction in granuloma site. Treatment of S. mansoni-infected mice with Met or PZQ/Met ameliorated the hematological and biochemical alterations induced by S. mansoni infection. Collectively, Met has no anti-schistosomal activity but led to a reduction in egg deposition and showed an anti-fibrotic effect on granulomatous development either when used alone or in combination with PZQ treatment. This study shed light on the possible role of Met as an anti-fibrotic agent when administered with PZQ for S. mansoni infected humans.