Core–shell structural PLGA nanoparticle of astaxanthin fabricated via micelle template for sustained release in vitro and long-term hepatoprotective effect in vivo

This study aimed to prepare core–shell structural PLGA nanoparticles of astaxanthin (ASTA-PLGA@M) via micelle template for sustained release in vitro and long-term hepatoprotective effects in vivo. The morphology, mean particle size, zeta potential, polydispersity index (PDI), and drug loading efficiency of optimized formulation were investigated. Meanwhile, the physicochemical characterizations including X-ray diffraction (XRD) and attenuated total reflectance-Fourier transform infrared (ATR-FTIR) of ASTA-PLGA@M were evaluated to prove the successful encapsulation of astaxanthin. The in vitro release of astaxanthin from ASTA-PLGA@M in four different media was sustained slowly for 120 h. An in vivo release study also demonstrated that ASTA-PLGA@M nanoparticles enhanced oral bioavailability significantly. In addition, the hepatoprotective effects of astaxanthin on oxidative stress (OS) accompanied by apoptosis in acute hepatic damage caused by carbon tetrachloride (CCl₄) in mice were investigated. ASTA-PLGA@M nanoparticles provide a clear elevating effect on the activity of SOD and inhibit the increase of MDA during acute liver damage caused by CCl4. Moreover, histopathological analysis was conducted to study the long-term hepatoprotective effects of ASTA-PLGA@M for further application of astaxanthin in functional food or clinical use.