Objective: To explore the protective effects of astragaloside IV on retinal ganglion cells (RGC) incubated under high glucose.
Methods: Cultured RGC-5 were divided into 3 groups: control, high glucose and high glucose+astragaloside IV. The survival rate of cell was measured by CCK-8 kit and flow cytometry. The changes of mitochondrial membrane potential were monitored by confocal laser scanning microscopy while those of RGC-5 mitochondria observed by electron microscopy.
Results: When the cell survival rate was 100% in the control group, the survival rate improved after 1 h 5, 10, 50, 100, 200 µg/ml astragaloside IV pretreatment and high-glucose culture. The cell survival rates for 100 mg/L, 200 mg/L of astragaloside IV were 81.6%, 80.0%, the difference from the high glucose group (66%) was significant (P < 0.05) and 100 mg/L of astragaloside IV was the best protection concentration. The apoptotic rate for 100 mg/L astragaloside IV pretreated group of RGC-5 cell was 6.1%. And it could partially inhibit the RGC-5 cell apoptosis caused by high glucose (8.2%) (P < 0.05). In the high-glucose group, the cells showed marked increases in mitochondrial swelling, especially for cristae. Numerous normal mitochondria were observed in 100 mg/L astragaloside IV pretreated group. Astragaloside IV could elevate mitochondrial membrane potential and alleviate mitochondrial swelling.
Conclusion: Astragaloside IV can protect RGC from high-glucose induced damage and may benefit the patients with diabetic retinopathy.