Osthole Preconditioning Protects Rats Against Renal Ischemia-Reperiusion Injury

Background. Renal ischemia-reperfusion (I/R) injury is a major cause of acute kidney injury. The pathogenetic mechanisms of renal I/R injury involve inflammation, oxidative stress, and apoptosis. Osthole, a natural coumarin derivative, has potential anti-inflammatory effects. This study investigated the effect of osthole on renal I/R injury and its potential mechanism. Methods. We induced renal I/R injury by clamping the left renal artery for 45 min followed by reperfusion, along with a contralateral nephrectomy. We randomly assigned 30 rats to 3 groups (n = 10): sham-operated, vehicle-treated I/R, and osthole-treated I/R. We treated rats intra-peritoneally with osthole (40 mg/kg) or vehicle (40 mg/kg) 45 min before renal ischemia. We harvested serum and kidneys at 24 h after reperfusion. Renal function and histological changes were assessed. The expression of tumor necrosis factor-alpha (TNF-alpha), interleukin-8 (IL-8), and interleukin-6 (IL-6) in renal tissue and serum were examined by means of RT-PCR and ELISA, respectively. The expression of p-p85, p85, p-Akt, Akt, p-p65, and p65 were measured by means of Western blotting. Results. Osthole pre-treatment significantly attenuated renal dysfunction, renal histological changes, NF-kappa B activation, and the expression of TNF-alpha, IL-8, and IL-6 induced by I/R injury, but the activation of PI3K/Akt signaling was further increased. Conclusions. Osthole pre-treatment protects rats against renal I/R injury by suppressing NF-kappa B activation, which is involved in PI3K/Akt signaling activation. Thus, osthole may be a novel practical strategy to prevent renal I/R injury.