The recombinant protein of scorpion venom phospholipase A2 exhibits potential anti-leishmanial activity

The venom of scorpions contains a diverse array of bioactive compounds, including mucoproteins, nucleotides, and enzymes. Among these, phospholipase A₂ (PLA₂) plays a critical role in hydrolyzing plasma membrane phospholipids, leading to the release of fatty acids and lysophospholipids. In this study, characterized Maurolipin was selected as a candidate for recombinant protein production and evaluation of its anti-leishmanial activity. The recombinant protein was expressed in Escherichia coli strain Origami (DE3) and purified using a Ni-NTA resin column. The anti-parasitic activity of Maurolipin was tested against Leishmania major promastigotes, the causative agent of zoonotic cutaneous leishmaniasis (ZCL). The growth inhibitory effect was assessed across a range of concentrations (40 to 0.07 μg/ml). Leishmanicidal activity was determined by propidium iodide (PI) staining and flow cytometry, while cytotoxicity to RAW 264.7 macrophages was evaluated using an MTT assay. Maurolipin exhibited potent anti-leishmanial effects, with a 24-hour growth inhibition IC₅₀ of 6.5 μg/ml and a leishmanicidal LC₅₀ of 9.06 μg/ml after 3 hours of exposure. Cytotoxic effects on macrophages were dose- and time-dependent. These findings suggest that recombinant Maurolipin possesses growth-inhibitory and apoptosis-inducing properties, highlighting its potential as a novel therapeutic agent for leishmaniasis.