Effect of Methotrexate and Dexamethasone Combination Therapy on Gene Expression in RPE Cells as an in Vitro Model for Proliferative Vitreoretinopathy
Mahdi Ravankhah 1 , Fatemeh Sanie-Jahromi 1 , Hossein Shafi Khani1 , Seyed Ahmad Razavizadegan 1 , M. Hossein Nowroozzadeh 1 *
- Poostchi Ophthalmology Research Center, Department of Ophthalmology, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
Abstract: The study explores the effects of a combination therapy using methotrexate (MTX) and dexamethasone (DEXA) on gene expression in retinal pigment epithelial (RPE) cells in vitro. Focused on addressing proliferative vitreoretinopathy (PVR), the research targets genes related to proliferation, inflammation, and epithelial-mesenchymal transition (EMT) in the context of this complex condition.
Methods: Human eye globes were obtained from cadavers, and RPE cells were cultured and treated with MTX and/or DEXA. The study design comprised two sets of experiments, assessing the effect of MTX serial dilution (0.5x, x, 2x, and 4x, where x=100 μg/ml) and the influence of MTX treatment alone or in combination with DEXA (50 μg/ml) on RPE cells at the transcriptional level. Real-time PCR was employed to quantify the relative expression of target genes.
Results: Treatment with MTX at the x concentration demonstrated a pro-apoptotic effect on RPE cells. The combination of MTX (x concentration) and DEXA significantly reduced the expression of inflammation-related genes (IL-1b, IL-6), indicating a synergistic anti-inflammatory effect. However, there was no significant impact on the expression of genes related to EMT, except for a partial neutralization of the reducing effect of MTX on ZEB1 and α-SMA genes.
Conclusion: This study highlights the potential pro-apoptotic effect of MTX (at the x dose) on RPE cells and the synergistic anti-inflammatory impact of MTX/DEXA combination therapy. Nevertheless, this combination did not significantly affect genes associated with EMT. Further research is required to elucidate the clinical implications of these findings in the management of PVR.
