Protective effect of Salvianolic acid A on ischaemia-reperfusion acute kidney injury in rats through protecting against peritubular capillary endothelium damages.

Renal ischaemia-reperfusion (I/R) injury is the most common cause of acute kidney injury (AKI). Peritubular capillary (PTC) endothelium damages are an important pathogenesis during I/R AKI. Salvianolic acid A (SAA) possesses various pharmacological activities. The study investigated whether SAA ameliorated I/R AKI through protecting against PTC endothelium damages. Male Sprague-Dawley rats were divided into 6 groups: control, sham, I/R, and I/R plus SAA (2.5, 5, 10 mg/kg) groups. Rats were subjected to bilateral renal pedicle clamping for 60 min, and killed at 24 hr after reperfusion. Kidney injury, PTC endothelium damages and factors affecting PTC endothelium were evaluated. SAA significantly decreased blood urea nitrogen and serum creatinine levels, and reduced urine kidney injury molecule-1 concentration. Simultaneously, SAA alleviated histological damages, prevented PTC endothelium damages, preserved the density of PTC and improved renal hypoxia. Furthermore, SAA inhibited platelet activation, elevated Klotho protein expression and up-regulated vascular endothelial growth factor A expression. Overall, SAA has protective effects on AKI induced by I/R. Preventing PTC endothelium damages and preserving PTC integrity to improve the renal hypoxia may be the ways for SAA to ameliorate AKI. All these indicate that SAA is likely to be a promising agent for AKI.