Role of mitochondrial dysfunction in hydrogen peroxide-induced apoptosis of intestinal epithelial cells.
OBJECTIVE
To study the role of mitochondrial dysfunction in hydrogen peroxide-induced apoptosis of intestinal epithelial cells.


METHODS
Hydrogen peroxide-induced apoptosis of human intestinal epithelial cell line SW-480 was established. Cell apoptosis was determined by Annexin-V and PI double-stained flow cytometry and DNA gel electrophoresis. Morphological changes were examined with light and electron microscopy. For other observations, mitochondrial function, cytochrome c release, mitochondrial translocation and membrane potential were determined simultaneously.


RESULTS
Percentage of apoptotic cells induced with 400 micro mol/L hydrogen peroxide increased significantly at l h or 3 h after stimulation and recovered rapidly. Meanwhile percentage of apoptotic cells induced with 4 mmol/L hydrogen peroxide increased with time. In accordance with these changes, we observed decreased mitochondrial function in 400 micro mol/L H2O2-stimualted cells at 1 h or 3 h and in 4 mmol/L H2O2-stimualted cells at times examined. Correspondingly, swelling cristae and vacuole-like mitochondria were noted. Release of cytochrome c, decreased mitochondrial membrane potential and mitochondrial translocation were also found to be the early signs of apoptosis.


CONCLUSIONS
Dysfunctional mitochondria play a role in the apoptosis of SW-480 cell line induced by hydrogen peroxide.
Li
Jian-Ming
JM
Institute of Burn Research, Southwest Hospital, Third Military Medical University, Chongqing 400038, China.
Zhou
Hong
H
Cai
Qian
Q
Xiao
Guang-Xia
GX
D017209:Apoptosis / Q000502:physiology*; D002460:Cell Line; D006801:Humans; D006861:Hydrogen Peroxide / Q000494:pharmacology*; D007413:Intestinal Mucosa / Q000187:drug effects* / Q000503:physiopathology*; D008564:Membrane Potentials; D008931:Mitochondria, Muscle / Q000502:physiology*; D016877:Oxidants / Q000494:pharmacology*
D016877:Oxidants; D006861:Hydrogen Peroxide