UCP2 alleviates tubular epithelial cell apoptosis in lipopolysaccharide-induced acute kidney injury by decreasing ROS production

Abstract

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. UCP2 expression was increased in tubular epithelial cells (TECs) treated with LPS. Accordingly, UCP2 expression was distinctly upregulated in renal tissues from the animals with LPS-induced AKI. Furthermore, UCP2 silencing dramatically aggravated LPS-induced apoptosis, accompanied by increased ROS production in renal tubular epithelial cell. Additionally, the inhibition of UCP2 by genipin, a specific UCP2 inhibitor, exacerbated the kidney injury of animals with LPS-induced AKI. Moreover, NAC (N-acetylcysteine), a potent ROS scavenger, obviously suppressed apoptosis induced by UCP2 silencing, which suggests that the increased ROS levels were associated with tubular epithelial cell apoptosis induced by UCP2 silencing. Therefore, UCP2 exerts a protective effect on the LPS-induced apoptosis of tubular epithelial cells by reducing excess ROS production. In conclusion, our findings highlight the renoprotective actions of UCP2 on inhibiting the production of apoptotic factors and oxidative stress to improve tubular cell survival in the LPS-induced AKI model.

Keywords

• Uncoupling protein-2
• AKI
• ROS
• Apoptosis