Abstract
Purpose :
Age-related macular degeneration (AMD) is the leading cause of vision loss among the elderly. There are no proven therapies for dry AMD. However, anti-VEGF drugs are used to treat wet (neovascular) AMD. We have demonstrated that transmitochondrial AMD cybrids (cells with identical nuclei but mitochondria from different AMD individuals) have impaired mitochondrial functions. The endosymbiotic theory states that the evolutionary origin of mitochondria (MT) was from ancestral aerobic bacteria. Therefore, there are many similarities between mitochondria and bacteria. Though some bactericidal antibiotics, such as fluoroquinolones (FLs) (e.g., Ciprofloxicin), are used frequently to treat various infections, evidence shows that these antibiotics can induce significant mitochondrial damage causing cell death. In our recent study on ARPE-19 and MIO-M1 (Müller) cells, cell viability and mitochondrial membrane potential (MMP) decreased after ciprofloxacin (CPFX) treatment, without significant changes in reactive oxygen species (ROS) levels.
We aim to identify possible damaging impacts of CPFX on AMD cybrid cells.
Methods :
AMD cybrid cells with the density of 104/well were cultured 24 hr in 96 well plates. Cells were treated 48 hr with CPFX concentrations of 30, 60 and 120 mg/ml. Assays to measure levels of cell viability (MTT), ROS (H2DCFDA) and MMP (JC-1) were performed. Each treatment was measured in twelve repeats. Experiments were repeated three times. Statistical analyses were performed by GraphPad Prism software. P values < 0.05 were considered significant.
Results :
The mean cell viability of treated cells with of 30, 60 and 120 ug/ml CPFX decreased to 78.21% ± 2.44, 70.62%± 2.55 and 39.56%± 2.49, respectively, compared to untreated cells (mean=100.3±2.52) (P<0.0001).
The mean of ratios in JC-1 assay diminished to 91.88%±2.01 (P=0.09), 87.89%±1.66 (P<0.0001) and 76.5%±2.04 (P<0.0001), compared to untreated cells (100.0 ± 2.25).
Though the mean of ROS in treated cells with 30 and 60 mg/ml CPFX did not change significantly, the ROS reduced to 93.96%±2.09 (P=0.02) with 120 mg/ml CPFX, compared to untreated group (mean=100±1.30).
Conclusions :
CPFX treatment, specifically at higher concentrations, induced significant negative effects on cellular viability and mitochondrial membrane potential of exposed cells. Therefore, AMD cybrids may be “damaged” by treatment with CPFX.
This is a 2020 ARVO Annual Meeting abstract.