Investigation of potential ascorbate peroxidase inhibitors for anti-leishmaniasis therapy

L eishmaniasis is a prevalent disease that impacts 98 countries and territories, mainly in Africa, Asia, and South America. It can cause substantial illness and death, particularly in its visceral manifestation that can be specifically targeted in the development of medications to combat leishmaniasis. This study has found natural compounds with possible inhibitory activity against APX using a reliable and accurate QSAR model. Despite the severe side effects of current treatments and the absence of an effective vaccination, these compounds show promise as a potential treatment for the disease. Nine hit compounds were found, and subsequent molecular docking was performed. Estradiol cypionate showed the lowest binding energy (- 10.5 kcal/mol), thus showing the strongest binding, and also had the strongest binding affinity, with a ΔG_Total of - 26.31 ± 3.01 kcal/mol, second only to the control molecule. Additionally, three hits viz. cloxacillin-sodium (- 16.57 ± 2.89 kcal/mol), cinchonidine (- 16.04 ± 3.27 kcal/mol), and quinine hydrochloride dihydrate (13.38 ± 1.06 kcal/mol) also showed significant binding affinity. Multiple interactions between drugs and active site residues demonstrated a substantial binding affinity with the target protein. The identified compounds exhibited drug-like effects and were orally bioavailable based on their ADME-toxicology features. Overall, estradiol cypionate, cloxacillin sodium, cinchonidine, and quinine hydrochloride dihydrate all exhibited inhibitory effects on the APX enzyme of Leishmania donovani. These results suggest that further investigation is needed to explore the potential of developing novel anti-leishmaniasis drugs using these compounds.