N-acetyltransferase is involved in baicalein-induced N-acetylation of 2-aminofluorene and DNA-2-aminofluorene adduct formation in human leukemia HL-60 cells.
Many arylamine and hydrazine drugs are acetylated by cytosolic N-acetyltransferase (NAT). The human promyelocytic leukemia cell line (HL-60) has been shown to acetylate arylamine and contain NAT activity. The purpose of this study was to determine whether or not baicalein could affect N-acetylation of 2-aminofluorene (AF) in HL-60 cells. Acetylated and nonacetylated AF were determined by using high performance liquid chromatography. Baicalein displayed a dose-dependent inhibition of cytosolic and intact cells' NAT activity and reduced the number of viable cells. Time-course experiments showed that N-acetylation of AF, measured from intact HL-60 cells, was inhibited by baicalein for up to 48 h. Baicalein also decreased AF-DNA adduct formation in the examined cells. The effects of baicalein on NAT were examined by flow cytometry and NAT gene expression was examined by polymerase chain reaction. The results demonstrated that baicalein inhibited NAT1 mRNA gene expression and reduced the level of NAT in HL-60 cells. These results show that baicalein can affect the NAT activity of human leukemia cells in vitro.
Li
Yu-Ching
YC
Department of Medical Technology, Chungtai Institute of Health Sciences and Technology, Taichung 406, ROC.
Tyan
Yu-Sheng
YS
Lee
Yih-Min
YM
Tsao
Tang-Yi
TY
Chuang
Jing-Yuan
JY
Kuo
Hsiu-Maan
HM
Hsia
Te-Chun
TC
Yang
Jen-Hung
JH
Chung
Jing-Gung
JG
D000107:Acetylation; D001191:Arylamine N-Acetyltransferase / Q000037:antagonists & inhibitors / Q000096:biosynthesis*; D002851:Chromatography, High Pressure Liquid; D018736:DNA Adducts / Q000096:biosynthesis*; D015536:Down-Regulation; D044950:Flavanones / Q000494:pharmacology*; D005449:Fluorenes / Q000378:metabolism*; D018922:HL-60 Cells; D006801:Humans; D007527:Isoenzymes; D012333:RNA, Messenger / Q000096:biosynthesis
C052668:2-aminofluorene-DNA complex; D018736:DNA Adducts; D044950:Flavanones; D005449:Fluorenes; D007527:Isoenzymes; D012333:RNA, Messenger; C012177:2-aminofluorene; C006680:baicalein; D001191:Arylamine N-Acetyltransferase; C089384:N-acetyltransferase 1