Prevention of acute kidney injury by low intensity pulsed ultrasound via anti-inflammation and anti-apoptosis

The therapeutic effects of low intensity pulsed ultrasound (LIPUS) on renal ischemia/reperfusion injury (IRI) with acute kidney injury (AKI) are still unclear. A renal tubule cell model under H₂O₂ or hypoxia/reoxygenation (H/R) conditions with or without LIPUS pre-treatment (1 MHz, 30 and 100 mW/cm², 15 min) was used to test the in vitro effects of LIPUS. An AKI mouse model of unilateral IRI with nephrectomy of the contralateral kidney for 48 h with or without LIPUS treatment (3 MHz, 100 mW/cm², 20 min/day) 5 day before IRI were used to investigate the in vivo effects of LIPUS. LIPUS significantly protected the renal tubule cell viability and prevented inflammatory signals against H₂O₂ challenge. LIPUS could inhibit the apoptosis-related molecular signals and increase the protein levels of endogenous antioxidant enzymes, α-Klotho, and Sirt1 in renal tubule cells after H/R challenge. LIPUS alleviated the increases in the serum levels of blood urea nitrogen, creatinine, and cystatin C, renal pathological changes and apoptosis-related molecular signals, and impaired antioxidant enzymes in AKI mice. The IRI-induced inflammatory responses in the kidneys and spleens could be reversed by LIPUS. These findings suggest that LIPUS treatment displays the benefits for renal protection in IRI-induced AKI mice.