Effect of Hesperidin on Expression of Inducible Nitric Oxide Synthase in Cultured Rabbit Retinal Pigment Epithelial Cells

Abstract

To study the effect of hesperidin on expression of inducible nitric oxide synthase (iNOS) in cultured rabbit retinal pigment epithelial (RPE) cells under the condition of high glucose in vitro. Hesperidin was extracted from Pericarpium Citri Reticulatae by ultrasound and ethanol precipitation and was detected qualitatively by high performance liquid chromatogram. The third to fifth primary cultured rabbit RPE were selected. The cells were divided into 6 groups including the control group cultured in DMEM, the model group cultured in DMEM containing 33 mmol/L glucose without any drug and four experimental groups which were exposed to hesperidin at the concentration of 10, 20, 40 and 80 mg/L at 37 degrees C under 5% CO(2) for 2 h and then cultured in DMEM containing 33 mmol/L glucose. The proliferation of RPE was measured by the MTT assay. The levels of NO produced were measured by spectrophotometry. The changes of iNOS expressed in RPE cells were determined with immunohistochemistry. The growth rate of RPE cells was associated with the concentration of hesperidin. NO production induced by high glucose was significantly inhibited by hesperidin. iNOS expression in hesperidin-treated group was decreased compared with the control group (p <0.001). Hesperidin can increase the proliferation of rabbit RPE cells, and inhibit the level of NO and iNOS expression, so hesperidin can protect rabbit RPE cells.