<title>Initiation of apoptosis by photosensitization with hypocrellin A and the repression of Vitamin E</title>

Abstract

PDT-induced HeLa cells apoptosis was evidenced by morphological changes, DNA fragmentation and decrease of mitochondria dehydrogenase activity. Apoptosis was associated with the formation of 1P3 of photosensitized cells and rapid release of Ca2 from intracellular pools. Vitamin E , which was added before irradiation, could significantly protect cells against cell death, indicating that reactive oxygen species (ROS) play an important role in apoptotic cell death.