Bioavailability,Anti-inflammatory And Antioxidant Activity Of Resveratrol-loaded Zein/Pectin Core-Shell Nanoparticles

As a plant-based polyphenol,resveratrol has a variety of functions that are beneficial to human health,but its application is limited due to factors such as water solubility and low bioavailability.Encapsulated resveratrol with nano-transport system is helpful to overcome these shortcomings.Nano-transport system based on zein is a hot research topic in recent years.Previously,resveratrol-loaded zein/pectin core/shell nanoparticles were developed and preliminary explored the antioxidant capacity in vitro by our groups.Therefore,this study is based on previous studies to explore the bioavailability of nanoparticle-encapsulated resveratrol through cell uptake,transmembrane transport in vitro,and oral absorption in vivo experiments,as well as combining post-digestion cell antioxidant tests with in vivo/vitro anti-inflammatory test to explore the intracellular antioxidant activity and anti-inflammatory ability of encapsulated resveratrol.The main findings were as follows:1.At the same dose,the absorption of encapsulated resveratrol on Caco-2 cells within 4 h was significantly higher than that of free resveratrol(pre-dissolved in DMSO)(p< 0.05).2.The amount of encapsulated resveratrol passing through the Caco-2 monolayer cell model at 4 h was nearly five times that of free resveratrol(p<0.05).3.In vitro anti-inflammatory experiments,the levels of inflammatory mediators and inflammatory factors were significantly inhibited,and the level of anti-inflammatory factor was promoted after encapsulated resveratrol treated compared with free resveratrol(p<0.05).Meanwhile,the levels of TLR4 protein and phosphorylation of MAPKs protein were inhibited by encapsulated resveratrol.4.Compared with free resveratrol,intracellular malondialdehyde(MDA)level was significantly reduced,and superoxide dismutase(SOD),glutathione peroxidase(GSH-Px)and catalase(CAT)activities were significantly increased after treatment with encapsulated resveratrol digestion solution(p<0.05),which exhibited strong ability to clear intracellular ROS level(p<0.05).5.During in vivo absorption,the content of resveratrol was not detected in the plasma given the free resveratrol aqueous dispersion solution?The maximum concentration of resveratrol in the plasma was found at 0.5 h after administration of the resveratrol PEG 400/water solution,but it was maintained until 2 h,and then decreased rapidly,and fell below the detection limit at 8 h.As for encapsulated resveratrol,the maximum concentration of resveratrol in the plasma was 4.4 times,and the half-time,average retention time and area under concentration-time curve were 3.1,7.5 and 16.5 times that of the resveratrol solution group,respectively.In vivo anti-inflammatory experiments have further confirmed that the levels of inflammatory factors and mediators were inhibited,and the release of anti-inflammatory factor was promoted by encapsulated resveratrol at low,medium and high concentrations(p<0.05),while free resveratrol had a certain anti-inflammatory effect only when given at high concentration.Meanwhile,the levels of MyD88,TRAF6,JNK,ERK1,ERK2 and p38 MAPK mRNA in the liver and lungs were more effectively inhibited after administration of encapsulated resveratrol,and it has a dose-effect relationship(p<0.05).In summary,resveratrol encapsulated in zein/pectin nanoparticles can increase the cellular uptake of resveratrol.Nanoparticle-encapsulated resveratrol improves the transmembrane transport of resveratrol by the simulated intestinal wall.At the same time,in vivo digestion and absorption experiment has proved that encapsulated resveratrol can continuously release resveratrol,which improves the bioavailability of resveratrol.Encapsulated resveratrol digestion solution has stronger cellular antioxidant capacity and ability to remove intracellular ROS than free resveratrol digestion solution.Compared with free resveratrol,encapsulated resveratrol improves its ability ofanti-inflammation in vitro/vivo,especially high concentration of encapsulated resveratrol,which can almost completely clear the inflammatory effects caused by LPS in vivo.