Flavonoid Luteolin Enhances Calcium Overload in Mouse Photoreceptors

ABSTRACT

Background Calcium overload is one of the main reasons that cause photoreceptor apoptosis during theirdegeneration. Our recent data show that flavonoid luteolin protects mouse retinal photoreceptors in diseasedmodel. Aim To explore how luteolin affects the calcium overload in mouse retinal photoreceptors. Methods Fluo4 AM was loaded into retinal slices of wild type mice. Fluorescent images were taken every 5s to monitor thechanges of calcium signal in the soma of photoreceptor. Tissue was perfused with Ringer’s solution as control,then luteolin for 10 min and then Ringer’s as washout. During the perfusion of each solution, high K+ solution wasapplied to elicit calcium overload in photoreceptors. Fluorescent intensity of the photoreceptor soma wasmeasured and compared between control and luteolin solution. Results The high K+ induced-peak fluorescentintensity of Fluo-4 after luteolin treatment was significant higher than that perfused with control solution.Conclusion Luteolin enhances calcium overload in mouse retinal photoreceptors.