The Effect Of Uncouping Protein 2 On The Lipopolysaccharide Induced Apoptosis In Renal Tubular Epithelial Cell

Objective:Uncoupling protein 2?UCP2?,an anion transporter,modulates the production of mitochondrial reactive oxygen species?ROS?and plays an important role in protecting against cell apoptosis.However,the role of UCP2 in sepsis-associated AKI remains unclear.In the present study,we investigated the role of UCP2 in LPS-induced AKI in vitro and in vivo.MethodsSepsis-AKI animal models were established by intraperitoneal injection of 10 mg/kg of LPS for 24h.Blood BUN and Scr was measured by commercial kits according to the manufacturer's instructions.Kidney sections were stained with HE staining for pathological changes.The expression level of UCP2 was tested by immunohistochemistry and Western blot.Cell apoptosis in tubular epithelial cells of kidney tissues was analyzed by TUNEL staining.The level of reactive oxygen species in kidney tissues was determined by Dihydroethidium.The expression level of relevant apoptosis proteins in NRK-52E cells were detected by Western blot.Cell apoptosis in NRK-52E cells were detected by Flow cytometry and Hoechst 33258 Staining.The cellular ROS level in the NRK-52E cells were tested by Dihydroethidium?DHE?,2?,7?-dichlorofluorescein diacetate?DCFH-DA?and MitoSOX^TMRed reagent.ResultsUCP2 expression was distinctly upregulated in renal tissues from the animals with LPS-induced AKI.Inhibition of UCP2 by genipin,a specific UCP2 inhibitor,exacerbated the kidney injury of animals with LPS-induced AKI,which include the increase of cell apoptosis and ROS level.Meanwhile,UCP2 expression was increased in tubular epithelial cells?TECs?treated with LPS,and UCP2 silencing dramatically aggravated LPS-induced apoptosis,accompanied by increased ROS productioninrenaltubularepithelialcell.Moreover,NAC?N-acetylcysteine?,a potent ROS scavenger,obviously suppressed apoptosis induced by UCP2 silencing.ConclusionOur research results indicated that UCP2 might play a renoprotective role by decreasing ROS production and subsequently attenuating TECs apoptosis in improving tubular cell survival in the LPS-induced AKI model.Strategies targeting UCP2 may be a potential therapeutic approach for septic AKI.