Forskolin eye drops improve retinal damage from ischemia/reperfusion

PURPOSE: To determine whether forskolin, a protein kinase A (PKA) agonist, eye drops could reduce neuronal and vascular damage after exposure to ischemia/reperfusion (I/R). METHODS: C57BL/6J mice were exposed to the I/R protocol. A group of mice were given forskolin eye drops (10 μM) daily. Two days after I/R, neuronal measurements were performed, while vascular measurements were performed at 10 days post-I/R. Western blotting was conducted to investigate whether forskolin could increase PKA levels and reduce the levels of inflammatory mediators. RESULTS: Forskolin statistically significantly increased PKA levels, but not exchange protein activated by cAMP 1 (Epac1). The forskolin eye drops also reduced neuronal and vascular damage compared to I/R alone. Tumor necrosis factor alpha (TNF-α) and interleukin-1-β (IL-1β) levels were statistically significantly reduced after administration of forskolin eye drops compared to I/R alone. CONCLUSIONS: Forskolin eye drops were protective against I/R. The findings offer a new therapeutic for local delivery.