Redox, redux: Journal pulls paper over data problems

Antioxidants & Redox Signalling has issued much more detailed retraction notice for a paper it pulled last year that was marred by duplicate data.

As we reported then, the journal’s initial notice for the 2011 article, titled “Inhibition of LXRa-dependent steatosis and oxidative injury by liquiritigenin, a licorice flavonoid, as mediated with Nrf2 activation,” was underwhelming:

THIS WORK HAS BEEN RETRACTED BY THE AUTHORS

Although we learned at the time that a reader, Paul Brookes, of the University of Rochester, had raised concerns about the article to the editors of ARS and other publications, we were glad to see that ARS has decided to make a clean breast of matters. The study has been cited by other papers three times, according to Thomson Scientific’s Web of Knowledge.

Here’s the notice, from editor Chandan K. Sen:

This work (1) has been retracted because data claimed by authors to be erroneous were published. Antioxidants &Redox Signaling (ARS) was thankfully alerted about possible data duplication by a reader who is also an ARS author. Briefly, the reader alleged that Figure 1 of the current work (1) and Figures 4 and 5 of another work by the same group (2) contained duplicated data. The reader noticed at least one case where identical data was represented as originating from two independent and unrelated experiments. It was also alleged that some data in Figure 2 of the retracted work (1) are repeated in Table 1 of another publication by the same group (3). Upon discussion with the corresponding author, it was found that the published manuscript (1) did contain incorrect data. The corresponding author acknowledged that erroneous figures were submitted and requested a retraction of their publication (1). The author statement explaining the retraction is published below.

That’s followed by an explanation from the corresponding/senior author Sang Geon Kim, of the College of Pharmacy and Research Institute of Pharmaceutical Sciences at Seoul National University, in South Korea:

At the invitation of the Editor of ARS, I write to explain why this article was retracted. The work was experimentally done mostly by the first author Young Woo Kim who was the first author of two different papers reporting on the antisteatotic effects of liquiritigenin (1) and sauchinone (2). An e-mail from the Editor-in-Chief of ARS triggered by concerns raised by a reader helped me recognize some significant errors in scientific reporting. Young Woo Kim presented the same immunohistochemical figures that had been published in the above-said paper (2) into the ARS publication (1) that is currently being retracted. Upon examination of raw data, I observed that there was an error in artwork submission. In addition, Young Woo Kim used control body weight parameters (normal diet and high fat diet alone) published in the above-said paper (2) for the comparison of liquiritigenin effect in the paper that is being currently retracted. Because Young Woo Kim wanted to compare the effects of the two treatment compounds, he in fact did part of the work all at the same time using several animal groups and shared the diet controls. As a Ph.D. student at the time, the first author was not aware of strictness of scientific reporting. Because the artwork mistake and the lack of statement on sharing of controls significantly compromised the value of the report, I decided to retract the paper. As senior author, I take full responsibility for the errors on behalf of my co-authors.

Although we commend the journal for publishing the notice and the author letter, we’re not big fans of how Sang Geon Kim treats his graduate student. Are we supposed to believe that Sang Geon Kim only examined the raw data once — after it was too late? If so, what role, exactly, did he play in the development of these manuscripts? And if Young Woo Kim truly was naive to the “strictness of scientific reporting,” as a graduate student, why didn’t he have that training on the job?

The two cited papers (aside from the one that has been retracted) are “Inhibition of SREBP-1c-mediated hepatic steatosis and oxidative stress by sauchinone, an AMPKactivating lignan in Saururus chinensis,” published in 2010 in Free Radic Biol Med, and  “Inhibition of liver X receptor-adependent hepatic steatosis by isoliquiritigenin, a licorice antioxidant flavonoid, as mediated by JNK1 inhibition,” which also appeared that year in the journal.

To our knowledge, neither of those has been retracted.