title: Cytotoxicity and apoptotic effects of tea polyphenol-loaded chitosan nanoparticles on human hepatoma HepG2 cells.
abstract: Tea polyphenols have strong antioxidant and antitumor activities. However, these health benefits are limited due to their poor in vivo stability and low bioavailability. Chitosan nanoparticles as delivery systems may provide an alternative approach for enhancing bioavailability of poorly absorbed drugs. In this study, tea polyphenol-loaded chitosan nanoparticles have been prepared using two different chitosan biomaterials, and their antitumor effects were evaluated in HepG2 cells, including cell cytotoxicity comparison, cell morphology analysis, cell apoptosis and cell cycle detection. The results indicated that the tea polyphenol-loaded chitosan nanoparticles showed a branch shape and heterogeneous distribution in prepared suspension. MTT assay suggested that tea polyphenol-loaded chitosan nanoparticles could inhibit the proliferation of HepG2 cells, and the cytotoxicity rates were increased gradually and appeared an obvious dose-dependent relationship. Transmission electron microscope images showed that the HepG2 cells treated with tea polyphenol-loaded chitosan nanoparticles exhibited some typical apoptotic features, such as microvilli disappearance, margination of nuclear chromatin, intracytoplasmic vacuoles and the mitochondrial swelling. In addition, the tea polyphenol-loaded chitosan nanoparticles had relatively weak inhibitory effects on HepG2 cancer cells compared with tea polyphenols. Tea polyphenols not only induced cancer cell apoptosis, but also promoted their necrosis. However, tea polyphenol-loaded chitosan nanoparticles exhibited their antitumor effects mainly through inducing cell apoptosis. Our results revealed that the inhibition effects of tea polyphenol-loaded chitosan nanoparticles on tumor cells probably depended on their controlled drug release and effective cell delivery. The chitosan nanoparticles themselves as the delivery carrier showed limited antitumor effects compared with their encapsulated drugs.
authors.affiliation: Key Laboratory of Tea Biochemistry and Biotechnology of Ministry of Education and Ministry of Agriculture, Anhui Agricultural University, Hefei 230036, People's Republic of China; College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095, People's Republic of China.
authors.forename: Jin
authors.initials: J
authors.lastname: Liang
authors.affiliation: College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095, People's Republic of China.
authors.forename: Feng
authors.initials: F
authors.lastname: Li
authors.affiliation: College of Food Science and Engineering, Nanjing University of Finance and Economics, Nanjing 210023, People's Republic of China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Fang
authors.affiliation: College of Food Science and Engineering, Nanjing University of Finance and Economics, Nanjing 210023, People's Republic of China.
authors.forename: Wenjian
authors.initials: W
authors.lastname: Yang
authors.affiliation: College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095, People's Republic of China.
authors.forename: Xinxin
authors.initials: X
authors.lastname: An
authors.affiliation: College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095, People's Republic of China.
authors.forename: Liyan
authors.initials: L
authors.lastname: Zhao
authors.affiliation: College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095, People's Republic of China.
authors.forename: Zhihong
authors.initials: Z
authors.lastname: Xin
authors.affiliation: College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095, People's Republic of China.
authors.forename: Lin
authors.initials: L
authors.lastname: Cao
authors.affiliation: College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095, People's Republic of China; College of Food Science and Engineering, Nanjing University of Finance and Economics, Nanjing 210023, People's Republic of China. Electronic address: qiuhuihu@njau.edu.cn.
authors.forename: Qiuhui
authors.initials: Q
authors.lastname: Hu
mesh_terms: D017209:Apoptosis / Q000187:drug effects*; D006528:Carcinoma, Hepatocellular / Q000473:pathology* / Q000648:ultrastructure; D002453:Cell Cycle / Q000187:drug effects; D002467:Cell Nucleus / Q000187:drug effects; D048271:Chitosan / Q000737:chemistry*; D056945:Hep G2 Cells; D006801:Humans; D008113:Liver Neoplasms / Q000473:pathology* / Q000648:ultrastructure; D053758:Nanoparticles / Q000633:toxicity* / Q000648:ultrastructure; D010316:Particle Size; D059808:Polyphenols / Q000494:pharmacology*; D013662:Tea / Q000737:chemistry*
chemical_list: D059808:Polyphenols; D013662:Tea; D048271:Chitosan
keywords: Apoptosis; Chitosan; Hepatoma; Nanoparticles; Tea polyphenols