Berberine-loaded chitosan nanoparticles protect against radiation-induced premature ovarian failure through modulation of PI3K-PTEN-Akt-FOXO3 pathway and autophagy-inflammasome signaling

Abstract

Premature ovarian failure (POF) is a common and clinically significant adverse effect of radiotherapy that lacks effective fertility-preserving pharmacological interventions. It is characterized by depletion of the primordial follicle pool driven by DNA damage, oxidative stress, and inflammation. Berberine (BBR) is a natural alkaloid with potent antioxidant and anti-inflammatory properties; however, its therapeutic application is limited by poor bioavailability. Nanoencapsulation within chitosan nanoparticles offers a promising strategy to enhance its bioavailability and therapeutic efficacy. This study evaluated the protective effects of BBR and berberine-loaded chitosan nanoparticles (BBR-CS-NPs) against γ-irradiation-induced POF in rats. Immature female Sprague-Dawley rats exposed to 3.2 Gy γ-irradiation received either free BBR or BBR-CS-NPs (10 mg/kg, i.p.). Ovarian protection was evaluated by histopathological, immunohistochemical, biochemical, and gene expression analyses, together with serum FSH, E2, and AMH measurements. Molecular docking was performed to investigate the interactions of BBR with HO-1, NLRP3, and Nrf2. γ-Irradiation induced the hallmark features of POF, including hormonal disturbances, follicular depletion, increased oxidative stress, granulosa cell apoptosis, upregulation of BAX, PI3K, Akt1, and NLRP3, and downregulation of Bcl2, FOXO3, PTEN, and LC3. Treatment with BBR-CS-NPs significantly improved ovarian indices, modulated the PI3K-PTEN-Akt-FOXO3 pathway, restored LC3-mediated autophagy, and suppressed NLRP3 inflammasome activation. Collectively, these findings support a protective role for BBR-CS-NPs against radiation-induced POF through modulation of the PI3K-PTEN-Akt-FOXO3 pathway and the autophagy-inflammasome axis.