[An experimental study on photosensitization of cultured human cells with hypocrellin A]

The photosensitive effects of hypocrellin A on cultured HeLa cells were studied by the methods of immunofluorescence cytochemistry, flow cytometry and others. The results showed that, in the presence of 3.66 mumol/L hypocrellin A, illumination of HeLa cells with visible light, the morphology was changed and the microvilli on the cells were disappeared; the proliferation of the cells decreased with increasing irradiated dose and this effect seemed more sensitive in tumor cells than in normal cells; the increased population of cycle cells at S phase but decreased at G1 phase were observed by FCM; the photodamage effect of hypocrellin A induced the sparse distribution of cytoplasmic microtubles and almost disappearance of the fluorescence intensity of MTOC, they were observed in HeLa cells as shown by immunofluoresent microscopy. All the aforesaid results indicated that photosensitization of hypocrellin A inhibits cells growth, resulting from the damage in cell membrane and cytoskeleton and S phase delay of the cell cycle.