Optical Microscopic Imaging Of Breast Cancer Cells Apoptosis Induced By Curcumin Nanoparticles

Mitochondria are important organelle to maintain normal cell function. The change of mitochondrial morphology and function is often related to apoptosis of events closely. Living cell fluorescence microscopy imaging is common and effective tool to study cell dynamics events in the field of biology for its rapid, non-destructive, high resolution. Curcumin is a natural anti-cancer drug and fewer side effect that attracts extensive attention worldwide. However, Curcumin is hardly soluble in water, fast in metabolism and decomposition, so as to restrict its bioavailbility and effectiveness. This paper adopted the method of laser confocal microscopy imaging to study the breast cancer cell apoptosis induced by curcumin and its related mechanism. First of all, we used nanomaterials of polyethylene glycol and poly has lactone (MPEG-PCL) wrap curcumin to form a new type of curcumin nanoparticles. We observed the nanoparticles morphology, studied the curcumin nanoparticles photophysical property and calculated the nanoparticles coating ratio and load ratio. Then, curcumin nanoparticles were incubated into two breast cancer cell lines with different estrogen receptor expression. We used optical imaging to study the cellular uptake, uptake process and location in organelles to curcumin and curcumin nanoparticles, and evaluated their effect on antitumor activity. Finally, curcumin nanoparticles were incubated into two breast cancer cell lines to induce apoptosis. We used the high resolution imaging system to observe and detect breast cancer cells’mitochondrial morphology, mitochondrial membrane potential and active oxygen content. The study showed that curcumin nanoparticles can effectively improve the cellular uptake of curcumin in breast cancer cells to increase the anti-cancer effects of curcumin. Curcumin nanoparticles are uptake by endocytosis mechanism, located in the mitochondria and lysosomes. Futhermore, in the process of cell apoptosis, mitochondrial morphological changed obviously, mitochondrial membrane potential decreased obviously, and cell active oxygen increased transiently. This suggests that curcumin could damage mitochondrial function to lead to apoptosis. The results of the study will be helpful for making mitochondrial dynamic behavior and function visual in process of apoptosis, and providing new ideas for targeting mitochondrial breast cancer treatment.