Matching Human Unilateral AKI, a Reverse Translational Approach to Investigate Kidney Recovery after Ischemia

Area of Science:

• Nephrology
• Translational Research
• Animal Models of AKI

Background:

• Uncertainty exists regarding the duration of renal ischemia leading to renal injury.
• A reverse translational research approach aims to enhance animal models of AKI for clinical relevance.
• This study developed murine models of unilateral renal ischemia to mirror a human study on renal injury during partial nephrectomy.

Purpose of the Study:

• To develop and validate murine models of unilateral acute kidney injury (UiAKI).
• To investigate the correlation between ischemia duration and short-term/long-term renal injury outcomes.
• To assess the translatability of animal models to human clinical findings.

Main Methods:

• Eight male mice underwent UiAKI or sham procedures.
• Functional, histological, and biomarker outcomes were assessed at various time points (2-28 days).
• Contralateral nephrectomy was performed in later cohorts to isolate the injured kidney's glomerular filtration rate.

Main Results:

• Short-term outcomes (24 hours) showed biomarker elevations consistent with human studies.
• Long-term outcomes (14-28 days) revealed increased fibrosis and reduced glomerular filtration rate in the injured kidney.
• Serum and urine biomarkers normalized in the long term, despite persistent histological and functional deficits.

Conclusions:

• Clinically available renal function biomarkers may be falsely reassuring regarding long-term injury after UiAKI.
• The duration of renal ischemia is a critical factor correlating with impaired kidney function and increased fibrosis.
• This study highlights the importance of considering ischemia duration in assessing AKI prognosis.