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Blue LED exposure caused corneal epithelial cell damage and ROS production. (A) Measurement of ROS production and (B) measurement of cell death rate. Date are expressed as meanS.E.M. (n6 to 8). ## p0.01 vs. Control, ** p0.01, * p0.05 vs. Blue LED exposed blank group (Students t-test).
Source publication
Blue light emitting diode (LED) light is being used various devices for recent decades. Blue LED light has the 450–500 nm wavelengths, and high photon energy compared with green or red LED light. It is known that the exposure to blue LED light causes retinal photoreceptor cells damage. It is unknown whether the blue LED light cut particle containin...
Citations
... Intracellular ROS were evaluated by a ROS indicator, CM-H 2 DCFDA (Thermo Fisher Scientific) as described previously [13]. CM-H 2 DCFDA was added to 661W cell cultures at a final concentration of 10 µM following blue light exposure for 8 h, then the fluorescence intensity (λex = 495 nm, λem = 527 nm) was measured using a microplate reader (Varioskan Flash 2.4; Thermo Fisher Scientific) immediately to obtain the signal of the background. ...
Background
Blue light exposure is known to induce reactive oxygen species (ROS) production and increased endoplasmic reticulum stress, leading to apoptosis of photoreceptors. Maqui berry (Aristotelia chilensis) is a fruit enriched in anthocyanins, known for beneficial biological activities such as antioxidation. In this study, we investigated the effects of Maqui berry extract (MBE) and its constituents on the subcellular damage induced by blue light irradiation in mouse retina-derived 661W cells.
Methods
We evaluated the effects of MBE and its main delphinidins, delphinidin 3-O-sambubioside-5-O-glucoside (D3S5G) and delphinidin 3,5-O-diglucoside (D3G5G), on blue light-induced damage on retinal cell line 661W cells. We investigated cell death, the production of ROS, and changes in organelle morphology using fluorescence microscopy. The signaling pathway linked to stress response was evaluated by immunoblotting in the whole cell lysates or nuclear fractions. We also examined the effects of MBE and delphinidins against rotenone-induced mitochondrial dysfunction.
Results
Blue light-induced cell death, increased intracellular ROS generation and mitochondrial fragmentation, decreased ATP-production coupled respiration, caused lysosomal membrane permeabilization, and increased ATF4 protein level. Treatment with MBE and its main constituents, delphinidin 3-O-sambubioside-5-O-glucoside and delphinidin 3,5-O-diglucoside, prevented these defects. Furthermore, MBE and delphinidins also protected 661W cells from rotenone-induced cell death.
Conclusions
Maqui berry may be a useful protective agent for photoreceptors against the oxidative damage induced by exposure to blue light.
Graphical abstract
