Curcumin Inhibits Replication of Human Parainfluenza Virus Type 3 by Affecting Viral Inclusion Body Formation

Figure 3

Curcumin inhibits the formation of viral IBs. (a) HeLa cells were incubated with curcumin or DMSO for 48 h, and the cell viability was examined as described above. There was no significant toxicity when cells were treated with 20 μM curcumin. (b, c) HeLa cells were cotransfected with plasmids encoding N-Flag and HA-P jointly by lipo3000 as per the manufacturer’s instruction. DMSO or curcumin were added at 12 h before sample collection. At 24 h posttransfection, cells were collected and fixed, mouse HA primary antibody and goat anti-mouse AF568 were used to stain P protein to visualize IBs, and nuclei were counterstained with DAPI. . The yellow arrow indicates IBs. Quantification for IBs is defined as the average number of IBs in each cell (IBs/cells), and IBs in at least 50 cells were calculated for each group. The histogram shows IBs/cells of the curcumin treatment group relative to the DMSO treatment group. Data are from three experiments. Student’s test: . (d, e) HeLa cells were infected with HPIV3_HA-P at an MOI of 1.0, curcumin were added at 24 h after infection, and samples were collected at 30, 36, 42, and 48 h postinfection. Then, the cells were fixed as described above, HA-P was immunostained to visualize IBs, and nuclei were counterstained with DAPI. . The yellow arrow indicates IBs. Quantification for IBs was calculated as described above. Data are from three experiments. Student’s test: .

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