title: Induction of autophagy and apoptosis by the extract of Solanum nigrum Linn in HepG2 cells.
abstract: Solanum nigrum L. (SN) has been used in traditional folk medicine to treat different cancers. It is also used as a hepatoprotective and anti-inflammatory agent. In this study, we demonstrated that the extract of SN (SNE) induced a strong cytotoxic effect toward HepG2 cells but much less to Chang liver and WRL-68 cells. The mechanisms of the cytotoxic effect were concentration-dependent. High doses of SNE (2 and 5 mg/mL) induced apoptotic cell death in HepG2 cells, as evidenced by increases in the expressions of p-JNK and Bax, mitochodrial release of cytochrome c, and caspase activation. On the other hand, cells treated with low concentrations of SNE (50-1000 microg/mL) revealed morphological and ultrastructural changes of autophagocytic death under electron microscopic observation. Furthermore, these cells showed increased levels of autophagic vacuoles and LC3-I and LC3-II proteins, specific markers of autophagy. The levels of Bcl-2 and Akt that have been implicated in the down-regulation of autophagy were decreased upon SNE treatment. Taken together, these findings indicate that SNE induced cell death in hepatoma cells via two distinct antineoplastic activities of SNE, the ability to induce apoptosis and autophagocytosis, therefore suggesting that it may provide leverage to treat liver cancer.
authors.affiliation: Institute of Biochemistry and Biotechnology, College of Medicine, Chung Shan Medical University, Taichung, Taiwan
authors.forename: Hui-Mei
authors.initials: HM
authors.lastname: Lin
authors.forename: Hsien-Chun
authors.initials: HC
authors.lastname: Tseng
authors.forename: Chau-Jong
authors.initials: CJ
authors.lastname: Wang
authors.forename: Charng-Cherng
authors.initials: CC
authors.lastname: Chyau
authors.forename: Ko-Kaung
authors.initials: KK
authors.lastname: Liao
authors.forename: Pei-Ling
authors.initials: PL
authors.lastname: Peng
authors.forename: Fen-Pi
authors.initials: FP
authors.lastname: Chou
mesh_terms: D017209:Apoptosis / Q000187:drug effects*; D001343:Autophagy / Q000187:drug effects*; D053148:Caspase 3 / Q000378:metabolism; D002460:Cell Line; D045744:Cell Line, Tumor; D045304:Cytochromes c / Q000378:metabolism; D005333:Fetus; D006801:Humans; D008099:Liver; D008113:Liver Neoplasms; D010936:Plant Extracts / Q000494:pharmacology*; D032324:Solanum nigrum / Q000737:chemistry*; D013274:Stomach Neoplasms
chemical_list: D010936:Plant Extracts; D045304:Cytochromes c; D053148:Caspase 3