Wogonin, an active compound in Scutellaria baicalensis, induces apoptosis and reduces telomerase activity in the HL-60 leukemia cells

Phytomedicine. 2010 Jan;17(1):47-54. doi: 10.1016/j.phymed.2009.06.005. Epub 2009 Jul 3.

Abstract

Crude extract of Scutellaria baicalensis (S. baicalensis) has cytotoxic effect on human myelogenous leukemia cells (HL-60). We invesigated which compound from the crude extract is responsible for the cytotoxic effect on HL-60 cells. We identified 29 compounds from the crude extract using high performance liquid chromatography mass spectrometry (HPLC/MS). Two of the compounds, baicalin and wogonoside, are converted to baicalein and wogonin, respectively, after treatment with beta-glucuronidase. We observed a dose-dependent reduction in cell viability when cells with either wogonin or aqueous extract of S. baicalensis. Several of the apoptotic features including deoxyribonucleic acid (DNA) fragmentation and increased caspase-3 activity were found in cells treated with wogonin and aqueous extract. The changes were associated with down-regulation of Bcl-2, and not Bax. Furthermore, treatment of HL-60 cells with wogonin or S. baicalensis led to the inhibition of human telomerase reverse transcriptase (hTERT), human telomerase-associated protein 1 (hTP1) and c-myc messenger ribonucleic acid (m-RNA) expression. Wogonin and S. baicaleisis down-regulated the telomerase activity. Our findings suggest that wogonin may be the major compound in S. baicalensis responsible for HL-60 growth inhibition in vitro. The inhibition of HL-60 cell growth is mediated partly through the induction of Bax/Bcl-2 apoptosis and by telomerase inhibition through suppression of c-myc, which is a promoter of hTERT.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antineoplastic Agents, Phytogenic / pharmacology
  • Antineoplastic Agents, Phytogenic / therapeutic use*
  • Apoptosis / drug effects*
  • Cell Line, Tumor
  • Cell Survival / drug effects
  • DNA-Binding Proteins / genetics
  • DNA-Binding Proteins / metabolism
  • Dose-Response Relationship, Drug
  • Down-Regulation
  • Flavanones / pharmacology
  • Flavanones / therapeutic use*
  • HL-60 Cells
  • Humans
  • Leukemia, Promyelocytic, Acute / drug therapy*
  • Membrane Transport Proteins / genetics
  • Membrane Transport Proteins / metabolism
  • Plant Extracts / chemistry
  • Plant Extracts / pharmacology
  • Plant Extracts / therapeutic use*
  • RNA, Messenger / metabolism
  • Scutellaria baicalensis / chemistry
  • Telomerase / antagonists & inhibitors*
  • Telomerase / genetics
  • Transcription Factors / genetics
  • Transcription Factors / metabolism
  • bcl-2-Associated X Protein / antagonists & inhibitors

Substances

  • Antineoplastic Agents, Phytogenic
  • DNA-Binding Proteins
  • Flavanones
  • MYCBP protein, human
  • Membrane Transport Proteins
  • Plant Extracts
  • RNA, Messenger
  • SEC62 protein, human
  • Scutellaria baicalensis extract
  • Transcription Factors
  • bcl-2-Associated X Protein
  • Telomerase
  • wogonin