Investigation of the Antiparasitic Potential of Luteolin: in vitro Activity and Comparison with Standard Therapeutics.

OBJECTIVE

Due to the limitations of current therapeutic approaches in treating parasitic diseases, there is a growing need for new and effective products, prompting interest in alternative approaches such as medicinal plants. Flavonoids, including luteolin, have shown promise in the treatment of many diseases due to their natural properties and pharmacological effects. This study aimed to investigate the in vitro activity of luteolin against Acanthamoeba castellanii (A. castellanii), Entamoeba histolytica (E. histolytica), and Leishmania tropica (L. tropica).

METHODS

The reference parasite strains were tested for antiparasitic activity using luteolin concentrations ranging from 200 to 1.5 μg/mL. Positive controls included chlorhexidine, metronidazole, and glucantime, while dimethyl sulfoxide and parasite specific culture medium served as negative controls. Parasite mortality was assessed XTT [2,3-bis (2-methoxy-4-nitro-5-sulphenyl)-(2H)-tetrazolium-5-carboxanilide] and trypan blue dye exclusion assays. Minimum inhibitory concentration (MIC) and median lethal dose (LD₅₀) values were determined via non-linear regression analysis.

RESULTS

Luteolin exhibited significant activity, with MIC values of 100 μg/mL for A. castellanii and E. histolytica, and 12.5 μg/mL for L. tropica. LD₅₀ analysis revealed effective concentrations of 3.125 μg/mL for E. histolytica and 1.5 μg/mL for A. castellanii, while L. tropica displayed an LD₅₀ below 1.5 μg/mL, indicating the highest sensitivity.

CONCLUSION

Luteolin demonstrated potent antiprotozoal effects in vitro, with L. tropica being the most susceptible, followed by A. castellanii and E. histolytica. Notably, luteolin's anti-leishmanial activity was comparable to glucantime. In conclusion, luteolin demonstrates significant potential as a broad-spectrum antiparasitic agent, and comprehensive in vivo studies are recommended to further evaluate its therapeutic efficacy.