RESUMO
AIM: To examine whether lipoxin A_4 (LXA_4) induces apoptosis of rat renal interstitial fibroblasts and explore the mechanisms. METHODS: Rat renal interstitial fibroblasts (NRK-49F cells) were incubated in RPMI-1640 medium supplemented with 5% fetal calf serum and exposed to LXA_4 at the concentration of 10 nmol/L, 100 nmol/L or 1 ?mol/L for 24 hours. Prior to experiment, some cells were transfected with calpain 10 antisense oligodeoxynucleotide. Apoptosis of cells was recognized by double staining using fluorescent dye acridine orange and ethidium bromide, observed under laser scanning confocal microscopy and counted by flow cytometry following propidium iodide and annexin staining. Activity of caspase-3 was measured by colorimetric assay. The expression of calpain 10 mRNA was determined by RT-PCR. RESULTS: LXA_4 at the concentration of 100 nmol/L or 1 ?mol/L induced 9.83% or 33.82% apoptosis of cells, respectively. Treatment of cells with LXA_4 up-regulated the expression of calpain 10 mRNA and increased the activity of caspase-3. The transfection of the cells with calpain 10 antisense oligodeoxynucleotide inhibited the LXA_4-induced apoptosis, activity of caspase-3 and expression of calpain 10. CONCLUSION: LXA_4 at high concentration induceds apoptosis in rat renal interstitial fibroblasts via up-regulating of calpain 10 mRNA expression.