In vitro and in vivo evaluation of kinase and protease inhibitors against Trypanosoma evansi

Trypanosoma evansi is a causative agent of chronic wasting and fatal disease of livestock and wild animals known as surra. In this study, repurposing approach based on drug target was used to investigate the efficacy of kinase inhibitors (Barasertib-HQPA, BAR and Palbociclib isethionate, PAL) and protease inhibitors (Z-pro-prolinal, Z-PRO and Leupeptin hemisulphate, LEU) against T. evansi in HMI-9 medium. BAR, PAL and Z-PRO exhibited IC50 values of 13.52 mu M, 0.6375 mu M and 63.20 mu M against T. evansi in terms of growth inhibition, in the contrary, LEU failed to exhibit a significant growth inhibition at any time interval. Furthermore, oligopeptidase B and aurora kinase genes of T. evansi were targeted to determine the effect of these drugs on quantitative mRNA expression, which showed significant (p < 0.01) up-regulation of both genes in the BAR and PAL-exposed population at 12 h of exposure, whereas, Z-PRO showed only significant (p < 0.05) up-regulation of aurora kinase gene at 12 h interval. In cytotoxicity assay, BAR exhibited 52% and 41% cytotoxicity at 50 mu M concentration (about five folds the IC50 value()) on equine PBMC's and Vero cell line, respectively. Similarly, the cytotoxicity of 25% and 24% were recorded at 10 mu M concentration (about ten folds to the IC50 value) of PAL in equine PBMC's and Vero cell line, respectively. Of these, BAR and PAL, which were found effective under in vitro trials, raised the longevity of mice at higher doses during in vivo trials. Data generated showed that kinase inhibitors have higher potential to explore therapeutic molecules against surra organism. Graphical abstract

Automated summary

This study investigated the efficacy of kinase inhibitors and protease inhibitors against Trypanosoma evansi, the causative agent of surra. The results showed that kinase inhibitors BAR and PAL, as well as protease inhibitor Z-PRO, exhibited significant growth inhibition against T. evansi. They also influenced the mRNA expression of certain genes in T. evansi. Furthermore, BAR and PAL showed cytotoxicity in equine PBMC's and Vero cell line. In vivo trials also showed the efficacy of BAR and PAL. These findings suggest that kinase inhibitors have potential as therapeutic molecules against surra.