In vitro efficacy of azithromycin against the larvae of Echinococcus multilocularis

Alveolar echinococcosis (AE) is a serious zoonotic parasitic disease caused by the larvae of Echinococcus multilocularis. Given the limitations of current medications, there is an urgent necessity for the development of novel pharmacological treatments for AE. Azithromycin, a macrolide antibiotic, exhibits both antibacterial and antiparasitic effects. This study aimed to investigate its effects on the viability of E. multilocularis larvae and to elucidate the underlying mechanisms. Ultrastructural changes were examined using scanning and transmission electron microscopy. Glucose assays, ROS assays, mitochondrial membrane potential assays, and Western blot were used to evaluate the in vitro effects of azithromycin on protoscoleces. Our results demonstrated that azithromycin treatment significantly decreased the viability of E. multilocularis protoscoleces and caused pronounced ultrastructural damage. Mechanistically, it significantly downregulated glucose transporter 1 (GLUT1) and protein kinase B (AKT) signaling, elevated ROS levels (P < 0.001), and decreased mitochondrial membrane potential. Furthermore, it downregulated the DNA damage marker γ-H2AX expression (P < 0.001) and induced ferroptosis, as evidenced by concurrent elevations in lipid peroxidation and Fe²⁺ (P < 0.001), along with reduced GSH content and diminished GPX4 and DHODH expression (P < 0.001). Collectively, azithromycin exerts multiple effects on protoscoleces, encompassing metabolic disruption, oxidative stress, and ferroptosis, thereby providing a mechanistic foundation for AE treatment.