Edaravone prevents high glucose-induced injury in retinal Müller cells through thioredoxin1 and the PGC-1α/NRF1/TFAM pathway.

CONTEXT: Oxidative injury in a high-glucose (HG) environment may be a mechanism of diabetic retinopathy (DR) and edaravone can protect retinal ganglion cells by scavenging ROS. OBJECTIVE: To explore the effect of edaravone on HG-induced injury. MATERIALS AND METHODS: First, Müller cells were cultured by different concentrations of glucose for different durations to obtain a suitable culture concentrations and duration. Müller cells were then divided into Control, HG + Vehicle, HG + Eda-5 µM, HG + Eda-10 µM, HG + Eda-20 µM, and HG + Eda-40 µM groups. Cells were cultured by 20 mM glucose and different concentrations of edaravone for 72 h. RESULTS: The IC50 of glucose at 12-72 h is 489.3, 103.5, 27.92 and 20.71 mM, respectively. When Müller cells were cultured in 20 mM glucose for 72 h, the cell viability was 52.3%. Edaravone significantly increased cell viability compared to Vehicle (68.4% vs 53.3%; 78.6% vs 53.3%). The EC50 of edaravone is 34.38 µM. HG induced high apoptosis rate (25.5%), while edaravone (20 and 40 µM) reduced it to 12.5% and 6.89%. HG increased the DCF fluorescence signal (189% of Control) and decreased the mitochondrial membrane potential by 57%. Edaravone significantly decreased the DCF fluorescence signal (144% and 132% of Control) and recovered the mitochondrial membrane potential to 68% and 89% of Control. Furthermore, HG decreased the expression of TRX1, PGC-1α, NRF1 and TFAM, which were restored by edaravone. DISCUSSION AND CONCLUSION: These findings provide a new potential approach for the treatment of DR and indicated new molecular targets in the prevention of DR.

[Characteristics of dark-adapted and light-adapted oscillatory potentials in human electroretinogram].

OBJECTIVE: To characterize dark-adapted and light-adapted oscillatory potentials (OPs) in human electroretinogram (EGR) elicited by flashing light stimulation of the same intensity. METHODS: Dark- and light-adapted ERGs of normal eyes were studied. The frequency spectra of the extracted dark-adapted OPs and light-adapted OPs were analyzed by a fast Fourier transform. The peak frequency, latency and total power of the OPs were determined. RESULTS: The averaged peak frequency, latency, and power of the dark-adapted OPs was 125.3∓9.93 Hz, 41.7∓3.56 ms, and 9.25∓5.55 (V·s)(2), as compared with 79.5∓6.79 Hz, 50.8∓5.36 ms, and 3.56∓2.18 (V·s)(2) for light-adapted Ops, respectively, showing significant differences in the parameters between dark- and light-adapted Ops (P<0.001). CONCLUSIONS: Compared with dark-adapted OPs, light-adapted Ops is characterized by a lower peak frequency and a lower power with a prolonged latency.