Fig. 5

HHT induced fibroblast apoptosis in vitro. a In vitro, fibroblast apoptosis was detected by annexin V-FITC/PI double labeling. The result was repeated for three times. *P < 0.05 versus the control group. b In vitro, TUNEL staining was used to detect the pro-apoptotic effect of HHT. All nuclei of fibroblasts were blue, and the nuclei of TUNEL-positive fibroblasts were green. Three fields were picked to count the percentage of apoptotic fibroblasts in every group. *P < 0.05 versus the control group. c, d Western blots shown that application of HHT could induce the expression of cleaved-caspase3, cleaved-PARP, and Bax, which were known as pro-apoptotic proteins, while decreased the expression of Bcl-2, which was considered as an anti-apoptotic protein. β-actin was used as a control. e Immunofluorescence study of the anti-cleaved-caspase3 showed that the expression of cleaved-caspase3 in the cytoplasm of fibroblasts treated with 2 ug/ml HHT increased significantly 24 h later