Journal: Frontiers in Cellular and Infection Microbiology
Article Title: Repurposing approved drugs targeting Leishmania infantum 5-Methylthioadenosine Phosphorylase as anti-leishmanial candidates
doi: 10.3389/fcimb.2026.1787791
Figure Lengend Snippet: In vitro evaluation of the effect of the active FDA-approved drugs against extracellular and intracellular L. major parasites, and against THP-1-derived macrophages. (A) In vitro evaluation of the effect of active FDA-approved drugs against L. major (Empa-12) promastigotes. Promastigotes in the stationary growth phase were seeded in 96-well plates at a cell density of 5x10 5 parasites/well and incubated with increasing compound concentrations of 1.56–200 µg/mL for Flupiritine, Indapamide, Leflunomide, Pentamidine, Dobutamine, and Labetalol; and 1.03–66 µg/mL for Halofuginone. After 24h of incubation, parasite viability was evaluated with an MTT assay except for Dobutamine, which was assessed by manual cell counting using a Malassez hemocytometer due to its interference with the MTT reagent. Dobutamine, Pentamidine and Labetalol showed a dose response effect on promastigotes parasites viability. The results were expressed as the percentage of promastigote viability treated with compounds relative to parasites treated with 1% DMSO. Data are shown as the mean values ± SD of three independent biological replicates, each carried out in technical duplicates. (B) In vitro viability and cytotoxicity effects of Labetalol, an Li MTAP inhibitor with anti-promastigote activity, against THP-1-derived macrophages. THP-1-derived macrophages were exposed to increasing concentrations of labetalol (1.56–200 µg/mL) for 24 (h) Cell viability was determined using the MTT assay, while cytotoxicity was assessed by measuring lactate dehydrogenase (LDH) release. Results are expressed as the percentage of viable cells relative to the 1% DMSO vehicle control, and LDH release as the percentage relative to the maximum LDH release (positive control). Data represent the mean ± SD of three independent experiments. (C) In vitro activity of Labetalol against Leishmania major (Empa-12) intracellular amastigotes. THP-1-derived macrophages were infected with the (L) major Empa-12 strain for 24 hours, then incubated for an additional 24 hours with increasing concentrations of Labetalol (0, 6.25, 9.37, 18.75, 25, 37.5, and 50 µg/mL). After treatment, cells were fixed and stained using the RAL 555 rapid stain kit. The number of intracellular amastigotes per 100 infected macrophages was counted for each condition (1% DMSO or compound-treated). Parasite viability was expressed as the percentage of parasites in treated cells relative to the DMSO control. Data represent the mean ± standard deviation (SD) from three independent experiments.
Article Snippet: MTAPase biochemical screening assays were performed using 96-well microplates (Greiner, UV-STAR ® MICROPLATTE, 96 WELL, COC, F-BODEN BIO-ONE, KAMINFORM, TRANSP.).
Techniques: In Vitro, Derivative Assay, Incubation, MTT Assay, Cell Counting, Activity Assay, Control, Positive Control, Infection, Staining, Standard Deviation
Greiner Bio is a verified supplier 
