Light emitting diode irradiation protect against the amyloid beta 25–35 induced apoptosis of PC12 cell in vitro

BACKGROUND AND OBJECTIVES: Whether light emitting diode (LED) irradiation has effects on "beta-amyloid (A beta) induced apoptosis," a leading hypothesis of the cause of Alzheimer's disease (AD), or not? STUDY DESIGN/MATERIALS AND METHODS: Monolayer cell cultures of PC12 were subjected to A beta or/and LED irradiation at various intensity. Cell apoptosis was confirmed by morphological criteria, DNA fragmentation assay, and FAScan flow cytometer assay. RESULTS: Treatment of the cells with LED irradiation significantly diminished A beta induced apoptosis within 24 hours. CONCLUSIONS: The LED irradiation, when utilized at power of 0.9 W/m(2) and 60 minutes has significantly diminished A beta induced apoptosis of PC12 cells.