title: Identification and anti-human glioblastoma activity of tagitinin C from Tithonia diversifolia methanolic extract.
abstract: The Tithonia diversifolia methanolic extract (TDM), which showed antiproliferative activity against human glioblastoma U373 cells, with an IC50 value of 59.2±3.7 μg mL(-1), was passed through silica gel chromatography and successively eluted with different percentages of EtOAc/hexane. The 10-60% EtOAc/hexane subfractions, which exhibited a comparatively higher antiproliferative activity, were isolated, and then structural identification was proceeded with 1H nuclear magnetic resonance. The isolated compound was tagitinin C, a kind of sesquiterpenoid. The IC50 value was 6.1±0.1 μg mL(-1) in U373 treated with tagitinin C. In flow cytometric analysis and inhibition of pan-caspase, the results showed that the anti-glioblastoma effect was apoptosis-independent. In PARP, p-p38, ULK1, and LC3-II expression, the anti-glioblastoma induced by tagitinin C was likely via autophagy. In the ULK1 siRNA transfection experiment, autophagy blockade counteracted the suppression induced by tagitinin C. The result suggested that tagitinin C induces U373 cell death dependent upon autophagy under certain conditions.
authors.affiliation: Department of Nutrition and Health Sciences, Chang Gung Institute of Technology, Taoyuan 333, Taiwan.
authors.forename: Ming-Yi
authors.initials: MY
authors.lastname: Lee
authors.forename: May-Hua
authors.initials: MH
authors.lastname: Liao
authors.forename: Yung-Nuan
authors.initials: YN
authors.lastname: Tsai
authors.forename: Kong-Hwa
authors.initials: KH
authors.lastname: Chiu
authors.forename: Hsiao-Chuan
authors.initials: HC
authors.lastname: Wen
mesh_terms: D000972:Antineoplastic Agents, Phytogenic / Q000737:chemistry* / Q000494:pharmacology; D017209:Apoptosis / Q000187:drug effects; D019659:Asteraceae / Q000737:chemistry*; D001343:Autophagy / Q000187:drug effects; D045744:Cell Line, Tumor; D005909:Glioblastoma / Q000188:drug therapy / Q000503:physiopathology*; D006801:Humans; D000432:Methanol; D010936:Plant Extracts / Q000737:chemistry* / Q000494:pharmacology; D012717:Sesquiterpenes / Q000737:chemistry* / Q000494:pharmacology
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D010936:Plant Extracts; D012717:Sesquiterpenes; C012565:tagitinin; D000432:Methanol