The Publisher and Editor are issuing an Expression of Concern on the article entitled “Agonists of Peroxisome-Proliferator Activated Receptor-Gamma Reduce Renal Ischemia/Reperfusion Injury” [Am J Nephrol. 2003;23(4):267–76; DOI: 10.1159/000072088] by Ahila Sivarajah, Prabal K. Chatterjee, Nimesh S.A. Patel, Zoran Todorovic, Yoshiyuki Hattori, Paul A.J. Brown, Keith N. Stewart, Helder Mota-Filipe, Salvatore Cuzzocrea and Christoph Thiemermann.

After the publication of this article, concerns were raised about the potential duplication of lanes in Figure 1B between PPARβ lane 2 and PPARγ1 lane 2 and between PPARβ lane 4 and PPARγ1 lane 3. Potential duplication of lanes was also identified in Figure 6A ICAM Northern blot within the I/R + VEH replicates and with the I/R + CIG 3 replicates.

The corresponding author stated that they cannot contact the co-author responsible for the experiments in these figures and that the original images are not available for review. The authors wish to inform readers that the results in Figure 1B and Figure 6A may not be reliable. The inhibition of ICAM-1 expression as a potential mechanism of action through which PPAR-γ agonists rosiglitazone and ciglitazone reduce the renal dysfunction and injury associated with I/R of the kidney proposed in the article may not be reliable.