DENV-2 induces apoptosis of EA.hy926 cells through mitochondrial pathway

AIM：To explore the effect of dengue virus type 2 (DENV-2) infection on the change of mitochondrial membrane potential (Δψm) in EA.hy926 cells. METHODS：The inhibitory effect of DENV-2 infection on EA.hy926 cell growth was examined by MTT assay. The changes of Δψm were analyzed by flow cytometry or observed under fluorescence microscope with JC-1 staining. The activity of caspase-9 was measured by a colorimetric kit. RESULTS：Infection of DENV-2 for 24 h, 36 h and 48 h inhibited the viability of EA.hy926 cells. After DENV-2 infection, the changes of Δψm in EA.hy926 cells were observed. Compared with the normal control cells, Δψm in DENV-2-infected EA.hy926 cells was notably decreased. The activity of caspase-9 increased at early stage after infection of DENV-2 and maintained at a high level at least to 48 h. CONCLUSION：DENV-2 infection decreases the mitochondrial membrane potential and increases the activity of caspase-9 in EA.hy926 cells in the early stage of proliferation, thus promoting the process of apoptosis.