Genotoxic and Protoscolicidal Effects of Gallic Acid and its Nanoformulation against Echinococcus granulosus Protoscoleces: In Vitro and Ex Vivo Insights from Egypt.

Cystic echinococcosis poses significant treatment challenges, as both medical and surgical options carry considerable risks. Gallic acid (GA), a naturally occurring polyphenol present in fruits, vegetables, and beverages, has demonstrated antimicrobial and antiparasitic effects. This study evaluated the protoscolicidal activity of GA, both in its free form and when encapsulated in mesoporous silica nanoparticles (MSNs-GA), against Echinococcus granulosus hydatid cyst protoscoleces under in vitro and ex vivo conditions. Albendazole sulfoxide (ABZ-SO) served as the positive control, while normal saline was the negative control. MSNs were synthesized, loaded with GA, and characterized for physicochemical properties. Protoscoleces were exposed to GA and MSNs-GA at concentrations of 25, 30, and 35 mg/ml for varying durations (3-60 min), and viability was assessed by eosin exclusion. Morphological alterations were examined using light and scanning electron microscopy, alongside DNA fragmentation analysis. MSNs-GA displayed spherical morphology (112.59 ± 5.81 nm), high encapsulation efficiency (99.13%), and controlled release behavior (9% over 48 h). Both free GA and MSNs-GA produced concentration- and time-dependent protoscolicidal effects, with maximum efficacy at 35 mg/ml after 60 min. In vitro, free GA achieved 89.72% mortality (IC₅₀ = 18.32 mg/ml), while MSNs-GA reached 74.72% (IC₅₀ = 21.51 mg/ml). Ex vivo, free GA and MSNs-GA achieved 68% and 61% mortality, respectively. Overall, free GA showed higher protoscolicidal efficacy than MSNs-GA under both in vitro and ex vivo conditions. Control groups showed minimal mortality: normal saline induced only 0.5% in vitro and 0.4% ex vivo, while DMSO caused 4% and 3%, respectively. The positive control ABZ-SO produced 68% mortality in vitro and 31% ex vivo after 60 min. SEM confirmed severe structural damage, including hook loss, tegument disruption, and soma body contraction, while DNA fragmentation supported significant genomic damage. These findings suggest GA, particularly in MSN formulations, shows promise as a controlled-release system for future in vivo evaluation in hydatid cyst disease.