Effects of indoleª²3ª²acetic acid oxidated by horseradish peroxidase on proliferation and MDA level of HeLa cells

    ZHOU Fuª²Ling, HUANG Chen, SONG Tuª²Sheng, NI Lei, WANG Aiª²Ying, NIU Yueª²Ying, LI Mingª²Zhong

    1Department of Oncologic Radiotherapy, First Hospital, 2Department of Biology, Xi¡¯an Jiaotong University, Xi¡¯an 710061, China

    ¡¾Abstract¡¿ AIM: To evaluate the effects of indoleª²3ª²acetic acid (IAA) oxidated by horseradish peroxidase (HRP) on the proliferation and malondialdehyde (MDA) level of HeLa cells. METHODS: HeLa cells were incubated by HRP/IAA(IAA 20, 40, 60, 80, 100 ¦Ìmol/L and HRP 1.2 mg/L) at various time points. The inhibition of proliferation activity, colonyª²forming rate, proliferation index, apoptosis rate, MDA level and morphological change of HeLa cells were detected by means of trypan blue dye, MTT reduction assay, colonyª²forming assay, flow cytometry, TBA test and QWin550CW microscope. RESULTS: HRP/IAA had a significant timeª²effect and doseª²effect reliance on the inhibition of proliferation and degradation of MTT in HeLa cells. The cell cycle of HeLa cells affected by HRP/IAA was investigated at 6 h, 24 h, 48 h and 72 h, respectively. It was showed that, with the increase of IAA concentration, HRP/IAA accelerated apoptosis and decreased the number of the HeLa cells in G0/G1 stages while increased the number of the HeLa cells slightly in S and G2/M stages. Colonyª²forming rate and protein reduced remarkably when IAA concentration increased, but MDA level rose. The changes of cell morphology were obvious after 72 h incubation with HRP/IAA. CONCLUSION: IAA oxidised by HRP has a rapid cytostatic effect on HeLa cells and enhances the lipid peroxidation. ......