spirulina platensis as a natural antileishmanial candidate: effective inhibition of lrv2+ and lrv2− leishmania major isolates in vitro

Background: drug resistance and treatment failure in leishmania infections are major concerns. leishmania rna virus 2 (lrv2) enhances host inflammation, indirectly favoring the parasite. thus, alternative treatments are needed. spirulina platensis has shown antimicrobial potential.methods: the alcoholic extract of s. platensis was tested against l. major with or without lrv2. anti-promastigote activity was evaluated directly on parasites, cytotoxicity on j774.a1 macrophages, and anti-amastigote effects using the mtt assay.results: the extract showed significant, dose-dependent anti-leishmanial activity against both lrv2+ and lrv2− promastigotes (ic₅₀ = 62.5 μg/ml). j774.a1 cells remained viable at 62.5–2000 μg/ml (p = 0.0005). amastigote growth was inhibited at 1000 and 2000 μg/ml in both strains.conclusion: s. platensis extract exhibits strong anti-leishmanial activity and low cytotoxicity, suggesting its potential as a natural therapeutic candidate against l. major, irrespective of lrv2 status. further in vivo studies are warranted.