Expression of concern.

Following the publication of this article and a corrigendum (1) correcting a microscopy image in Figure 7C, the authors informed the editorial board that multiple histology images in Supplemental Figures 7 and 11 were incorrect. The db/+ vehicle image in Supplemental Figure 7A (representing 30 days of treatment) was taken from the same tissue block as the db/+ vehicle image in Supplemental Figure 7B (representing 2 months of treatment). Additionally, the db/db vehicle and db/db TRO samples in Supplemental Figure 7B were taken from a common tissue block. In Supplemental Figure 11A, the WT TRO image (representing 30 days of treatment) was from the same tissue block as the WT TRO image in Supplemental Figure 11B (representing 2 months of treatment). Finally, the CMT1A vehicle image in Supplemental Figure 11A was derived from the same tissue block as the CMT1A TRO image in Supplemental Figure 11B. The authors have stated that these errors were due to an archiving problem. Because the authors have used images from the same tissue block to represent different treatment conditions, the editorial board is pursuing further investigation of this matter. We will inform our readers of the outcome when the investigation is complete.