The
Fanconi syndrome is a common side effect of the chemotherapeutic agent
ifosfamide. Current evidences suggest that
chloroacetaldehyde (CAA), one of the main metabolites of
ifosfamide activation, contributes to its nephrotoxicity. However, the pathophysiology of CAA-induced
Fanconi syndrome is not fully understood. The present work examined the adverse effects of CAA on precision-cut rat renal cortical slices, which allowed studying the toxic effect of CAA on proximal endocytosis. We demonstrated that clinically relevant concentrations of CAA (< or =200 microM) are able to inhibit the uptake of
horseradish peroxidase, a marker of proximal tubular cell endocytosis in renal tubular proximal cells. CAA > or =75 microM has adverse effects, both on viability parameters and on energy metabolism, as shown by the great decrease in total
glutathione and
ATP levels. In addition, the V-
ATPase, which plays a crucial role in intracellular vesicle trafficking, was inhibited by 100 microM of CAA. By contrast, the slight decrease in Na-K-
ATPase activity observed for CAA> or = 125 microM (maximum inhibition: 33%) could not totally explain the inhibition of the reabsorption processes. In conclusion, the addition of the two main adverse effects of CAA (decrease in
ATP levels and inhibition of the V-
ATPase) could explain the inhibition of endocytosis and the
Fanconi syndrome observed during
ifosfamide treatments.