Ageing mouse kidney--not always the SAME old story.

Area of Science:

• Gerontology
• Nephrology
• Animal Models

Background:

• Growing interest in the ageing kidney necessitates reliable experimental models.
• Reproducibility challenges in aged animal studies are a significant concern.
• Animal provenance is an underappreciated factor contributing to experimental heterogeneity.

Purpose of the Study:

• To investigate the impact of supplier-dependent variations on renal ageing studies.
• To identify potential sources of irreproducibility in experiments using aged mice.
• To emphasize the importance of baseline characterization of aged animal models.

Main Methods:

• Procurement of male C57BL/6J mice (19-22 months old) from four distinct suppliers.
• Assessment of baseline renal function via serum urea, creatinine, and proteinuria measurements.
• Histopathological analysis of renal morphology, including glomerulosclerosis, interstitial fibrosis, and amyloid deposition.

Main Results:

• Three suppliers provided mice with normal renal ageing characteristics.
• One major European supplier provided mice exhibiting significant renal pathology.
• Pathological findings included elevated serum urea and creatinine, increased proteinuria, massive glomerulosclerosis, amyloid deposits, and interstitial fibrosis.

Conclusions:

• Supplier-specific variations can explain irreproducibility in renal ageing research.
• Thorough baseline analysis of animal provenance is essential before conducting in vivo experiments.
• Standardizing animal sourcing and baseline characterization can enhance experimental reliability.