Hedyotis diffusa Willd extract protects rat renal tubular epithelial cells from high glucose-induced injury by inhibiting PI3K/AKT signaling pathway

The effects of Hedyotis diffusa Willd on high glucose (HG)-induced injury of rat renal tubular epithelial cells and its related regulatory mechanisms were investigated. In this study, NRK-52E cells were cultured in a normal glucose concentration (5.5 mM glucose) or HG concentration medium (30 mM glucose), and treated with the concentration gradient of H. diffusa extract (50, 100, 200 ??g/ml). The results suggested that H. diffusa extract has a protective effect on the cell viability of NRK-52E cells and inhibited the HG-induced oxidative stress through the detection of malondialdehyde content and specific activities of superoxide dismutase and glutathione peroxidase. The extract also inhibited the HG-induced apoptosis. In addition, the epithelial-to-mesenchymal transition (EMT) indicators including alpha-smooth muscle actin (??-SMA), E-cadherin, N-cadherin and vimentin were measured, it was found that the HG -induced EMT of NRK-52E cells was inhibited by the extract. Moreover, H. diffusa extract exerted an inhibitory effect on the PI3K/AKT signaling activation induced by HG. Hence, H. diffusa extract could protect rat renal tubular epithelial cells from HG-induced injury by inhibiting PI3K/AKT signaling pathway.