The Protective Effect of Genipin on Oxidative Stress Under Hypoxia and Hyperglycemia in Retinal Pigment Epithelial Cells

Abstract

We aimed to explore the protective effect of genipin on retinal pigment epithelial (RPE) cells under hypoxia and hyperglycemia. RPE cells were cultured under hyperglycemia and hypoxia mimicking agent DFX. The cells were then exposed to genipin (10–50 μM), genipin + phospha-tidylinositol (3,4,5) trisphosphates (PIP3) as phosphoinositide 3-kinase (PI3K) inhibitor, and genipin+ PI3K agonist, followed by CCK-8 assay to detect the cell viability. Western blot determined PI3K/protein kinase B (AKT) pathway, and apoptosis- and anti-apoptosis-related proteins levels. MitoSOXTM Red kit was conducted to analyze reactive oxygen species (ROS) content. Finally, confocal immunofluorescence staining assessed nuclear translocation of Nuclear factor erythroid-derived 2-like 2 (Nrf2). Hyperglycemia and hypoxia treatment induced injury in RPE cells, with nuclear translocation of Nrf2 and ROS production. Importantly, administration of genipin alleviated the injury, up-regulated Bcl-2 expression, inhibited caspase-3 activity and nuclear translocation of Nrf2, and down-regulated the level of Bax and ROS. In addition, genipin pretreatment obviously increased PI3K and Akt phosphorylation and promoted cell proliferation and viability. On the contrary, PI3K inhibitor inactivated PI3K/AKT and decreased cell viability while PI3K agonist showed the opposite effect. Genipin prevented oxidative stress and apoptosis induced by hyperglycemia and hypoxia through PI3K/Akt signaling pathway.

Influence of Optimal Management of Hyperglycemia and Intensive Nursing on Blood Glucose Control Level and Complications in Patients with Postoperative Cerebral Hemorrhage

“…Neuroendocrine disorders can also lead to insulin resistance in the body [10][11][12]. Hematoma compression can lead to hypothalamuspituitary-adrenal axis injury and reduce the biological uptake and utilization of glucose in peripheral tissues [13,14]. In contrast, hyperglycemic state can affect brain tissue energy metabolism, leading to acidosis due to lactic acid accumulation and can induce oxidative stress, which aggravates neuronal cell damage and is detrimental to the prognosis of patients with cerebral hemorrhage [15,16].…”