On the basis of the recommendation of the American Diabetes Association’s Panel on Ethical Scientific Programs (ESP), the American Diabetes Association, the publisher of Diabetes, is issuing this expression of concern to alert readers to questions about the reliability of the data in the above-cited article.

After readers of the journal contacted Diabetes about potentially duplicated images in the article, the ESP contacted the corresponding author to request explanations for the reported anomalies. Replying on behalf of all authors, the corresponding author responded that the images were similar but unique, and he provided source images and detailed visual analyses to support the originality and integrity of the data.

After reviewing the source files and the analyses, however, the ESP's concerns over the authenticity and reliability of several reported images were not sufficiently allayed, and the Panel's concerns were subsequently magnified after learning of additional instances of possible duplication. Therefore, the ESP has contacted the corresponding author's institution, Università degli Studi di Napoli Federico II, Naples, Italy, to request an institutional investigation of the following issues:

  • Figure 4A appears to contain several potentially duplicated images:

    • ∘ In the “I.P. α-IR W.B. α-IR” strip, all lanes on the blot image appear to be duplicated.

    • ∘ In the “α-actin” strip, lanes 1, 3, and 5 and lanes 2, 4, and 6 appear to be duplicates.

  • The “α-actin” strip in Fig. 2B appears to be republished as lanes 1–3 of the “I.P.α-IRS1 W.B. α-IRS1” strip in Fig. 4A, with size and contrast adjustments. These images (including lane 4 of the “I.P.α-IRS1 W.B. α-IRS1” strip in Fig. 4A) appear to have been previously published—with size, brightness, and sharpness adjustments—as the “α–14-3-3β” strip of Fig. 4A and the “α–PKC-α” strip in Fig. 6D of the following paper:

  • These images also appear to have been later published as the actin panel in Fig. 2C of the following paper:

  • Lanes 4–6 of the “I.P.α-IRS2 W.B. α-IRS2” strip in Fig. 4A appears to have been republished as lanes 1–3 the “α-actin” strip in Fig. 6C of this article. These images (including lane 4 of Fig. 6C) appear to have been later published, with size and contrast adjustments, as the “SMAD 3” strip of Fig. 2C in the 2012 Cell Death and Differentiation article cited above.

Diabetes is a member journal of the Committee on Publication Ethics (COPE) (publicationethics.org). As such, the editors of the journal and the ESP refer to COPE’s guidelines and recommendations when reviewing such matters. Diabetes will make a final decision on the publication status of this article after the journal obtains more information about the reliability of the data and conclusions presented in the article.

Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered. More information is available at http://www.diabetesjournals.org/content/license.