title: Protective role of intestinal bacterial metabolism against baicalin-induced toxicity in HepG2 cell cultures.
abstract: Baicalin, a glycoside present in Scutellaria baicalensis Georgi, is metabolized to its aglycone, baicalein, in intestine. In the present study, possible role of metabolism of baicalin by intestinal bacteria to baicalein in baicalin-induced toxicity was investigated in HepG2 cell cultures. As an intestinal bacterial metabolic system for baicalin, human fecal preparation containing intestinal microflora (fecalase) was employed. Initially, when cytotoxic effects of baicalin and baicalein were compared, baicalin was more cytotoxic than baicalein in HepG2 cells. When baicalin was incubated with fecalase, it was metabolized to baicalein. In addition, baicalin-incubated with fecalase reduced cytotoxicity of HepG2 cells in a concentration-dependent manner. Moreover, baicalin-incubated with fecalase significantly caused an increase in Bcl-2 expression together with a decrease in Bax expression and cleaved Caspase-3. Furthermore, anti-apoptotic effect by the incubation of baicalin with fecalase was also confirmed by the terminal deoxynucleotidyltransferase-mediated dUTP-biotin nick-end labeling assay. Taken all together, the findings suggested that metabolism of baicalin by human fecalase to baicalein might have protective effects against baicalin-induced toxicity in HepG2 cells.
authors.affiliation: Department of Toxicology, College of Pharmacy, Chungnam National University, Daejeon, South Korea.
authors.forename: Tilak
authors.initials: T
authors.lastname: Khanal
authors.forename: Hyung Gyun
authors.initials: HG
authors.lastname: Kim
authors.forename: Jae Ho
authors.initials: JH
authors.lastname: Choi
authors.forename: Bong Hwan
authors.initials: BH
authors.lastname: Park
authors.forename: Minh Truong
authors.initials: MT
authors.lastname: Do
authors.forename: Mi Jeong
authors.initials: MJ
authors.lastname: Kang
authors.forename: Hee Kyung
authors.initials: HK
authors.lastname: Yeo
authors.forename: Dong Hyun
authors.initials: DH
authors.lastname: Kim
authors.forename: Wonku
authors.initials: W
authors.lastname: Kang
authors.forename: Tae Cheon
authors.initials: TC
authors.lastname: Jeong
authors.forename: Hye Gwang
authors.initials: HG
authors.lastname: Jeong
mesh_terms: D017209:Apoptosis; D001419:Bacteria / Q000378:metabolism*; D053148:Caspase 3 / Q000235:genetics; D002470:Cell Survival; D005243:Feces / Q000382:microbiology*; D044950:Flavanones / Q000633:toxicity*; D005419:Flavonoids / Q000633:toxicity*; D056945:Hep G2 Cells; D006801:Humans; D007422:Intestines / Q000382:microbiology; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000235:genetics; D012333:RNA, Messenger / Q000378:metabolism; D051028:bcl-2-Associated X Protein / Q000235:genetics
chemical_list: C494826:BAX protein, human; D044950:Flavanones; D005419:Flavonoids; D019253:Proto-Oncogene Proteins c-bcl-2; D012333:RNA, Messenger; D051028:bcl-2-Associated X Protein; C038044:baicalin; C006680:baicalein; D053148:Caspase 3