SUMMARYCyclophilins are target molecules for cyclosporin A (CsA), an immunosuppressive antimicrobial drug. We have previously reported thein vitroanti-Trypanosoma cruziactivity of H-7-94 and F-7-62 non-immunosuppressive CsA analogues. In this work, we continue the study of the parasiticidal effect of H-7-94 and F-7-62 CsA analoguesin vitroandin vivoand we analyse 3 new CsA derivatives: MeIle-4-CsA (NIM 811), MeVal-4-CsA (MeVal-4) and D-MeAla-3-EtVal-4-CsA, (EtVal-4). The most efficient anti-T. cruzieffect was observed with H-7-94, F-7-62 and MeVal-4 CsA analogues evidenced as inhibition of epimastigote proliferation, trypomastigote penetration, intracellular amastigote development andin vivo T. cruziinfection. This trypanocidal activity could be due to inhibition of the peptidyl prolylcis-transisomerase activity on theT. cruzirecombinant cyclophilins tested. Furthermore, CsA and F-7-62 derivative inhibited the efflux of rhodamine 123 fromT. cruziepimastigotes, suggesting an interference with a P-glycoprotein activity. Moreover, H-7-94 and F-7-62 CsA analogues were not toxic as shown by cell viability and by aminopyrine-N-demethylase activity on mammalian cells. Our results show that H-7-94, F-7-62 and MeVal-4 CsA analogues expressed the highest inhibiting effects onT. cruzi, being promissory parasiticidal drugs worthy of further studies.
In Vivo Effects of Cyclosporin A and Ketoconazole on the Pharmacokinetics of Representative Substrates for P-Glycoprotein and Cytochrome P450 (CYP) 3A in Rats