The Mechanism Of Apoptosis Induced By A Novel Acetophenone Derivative In Human Leukemia HL-60Cells

In recent years,acetophenone derivatives has a unique position in thepharmaceutical formulation. Acetophenone derivatives showed good biologicalactivity in pharmaceuticals, and already became one of the hot spots for bio-chemicalindustry and academic research.In this study, HL-60cells was employed to assess the toxicity of1-(4-(allyloxy)-3-hydroxyphenyl)-2-chloroethanone, and the mechanism of cellapoptosis induced were further explored. The results are shown as follows:(1) The MTT assay results exhibited,1-(4-(allyloxy)-3-hydroxyphenyl)-2-chloroethanone showed high cytotoxicity to HL-60cells, and in dose-andtime-dependent manners, with IC5010.96and7.01μmol/L treated in24and48h,respectively. When stained by Giemsa or Hoechst33258,the cell displaied thatchromatin condensation, nuclei fragmentation and multi-core state clearly, exhibitedthe morphologyical features of apoptosis.(2) Flow cytometry assay stained by propidium iodide (PI) displayed that lowerlevels (10μmol/L) compound mainly caused HL-60cells arrest in G2/M phase incell cycle and induced a small amount cell apoptosis.When the concentrationincreased to20μmol/L, G2/M phase cells decreased and the apoptosis cells wereincrease significantly.The G2/M phase arrest is the result of activated checkpoint bycell DNA damage, so the cycle arrest of G2/M may be one of the ways to causeapoptosis in HL-60cells by this chemical.(3)The increase of ROS and the decrease of GSH content in HL-60cells weredetected by flow cytometry assay with DCFH-DA staining and detection kit, and theyare corresponding under the same compound concentrations and the treatment time,indicating that the compound caused the increase oxidative stress in HL-60cells.(4) The MTT assay of survival rate showed NAC owed obvious protectiveeffect to HL-60treated by1-(4-(allyloxy)-3-hydroxyphenyl)-2-chloroethanone. Celldensity rebound, cell debris reduction and cell body became round under the invertedmicroscope. Intracellular ROS content decreased obviously in the combined treatmentgroup.The above data showed that NAC inhibited the oxidative damage by thiscompounds on HL-60cells through reducing ROS content, demonstrated that the increase of ROS content play an important role in HL-60cells apoptosis induced bythe compound.(5) The GSH content of the combined group did not rise significantly, comparedwith1-(4-(allyloxy)-3-hydroxyphenyl)-2-chloroethanone treatment alone in24h.Thatmay means NAC have no effect on intracellular GSH content, which probablyrelated to the antioxidant activity of NAC action mode.All the above results suggested that the mechanism of HL-60cells apoptosisinduced by1-(4-allyloxy-3-hydroxy)-2-chloroacetophenone may be increasingintracellular ROS content.