Induction of apoptosis in mouse fibroblast cell line L929 by arachidonic acid

AIM: To observe whether arachidonic acid (AA) could induce apoptosis in mouse fibroblast cell line L929 and the potential mechanism involved. METHODS: The viability and damaged degree of L929 was monitored by MTT and the release of lactate dehydrogenase (LDH). Lipid peroxidation in L929 was measured as malondialdehyde (MDA) content by colorimetric assay. Hoechst 33258 staining was used to observe AA-induced morphological changes. Agarose gel electrophoresis was used to detect DNA fragmentation. RESULTS: Treatment of L929 cell with AA for 24 h, in the range of 40-160 μmol/L, caused a great decrease in cell survival and increased MDA contents and the release of LDH simultaneously (P＜0.01). Cells treated by 160 μmol/L AA showed typical morphological changes of apoptosis. A "ladder" pattern representing fragmentation of DNA into oligonucleosome length fragments was observed 24 h after AA treatment. CONCLUSION: Higher concentration of arachidonic acid (80-160 μmol/L) induced apoptosis in mouse fibroblast cell line L929. The mechanism of its action might be related to lipid peroxidation.