pNaKtide inhibits Na/K-ATPase reactive oxygen species amplification and attenuates adipogenesis
Authors: Zijian Xie
Kyle Maxwell
Yanling Yan
Nader G Abraham
Muhammad A Chaudhry
Komal Sodhi
Jiang Liu
Morghan Getty
Joseph I Shapiro
Journal: Science Advances (2015)
Discipline: Multidisciplinary
Keywords: Na/K-ATPase; adipogenesis; high-fat diet; metabolic syndrome; oxidative stress
Affiliations: Departments of Medicine, Pharmacology, and Surgery, Joan C. Edwards School of Medicine, Marshall University, Huntington, WV 25701, USA., Departments of Medicine, Pharmacology, and Surgery, Joan C. Edwards School of Medicine, Marshall University, Huntington, WV 25701, USA. ; Department of Medicine, New York Medical College, Valhalla, NY 10595, USA.

Abstract:  Obesity has become a worldwide epidemic and is a major risk factor for metabolic syndrome. Oxidative stress is known to play a role in the generation and maintenance of an obesity phenotype in both isolated adipocytes and intact animals. Because we had identified that the Na/K-ATPase can amplify oxidant signaling, we speculated that a peptide designed to inhibit this pathway, pNaKtide, might ameliorate an obesity phenotype. To test this hypothesis, we first performed studies in isolated murine preadipocytes (3T3L1 cells) and found that pNaKtide attenuated oxidant stress and lipid accumulation in a dose-dependent manner. Complementary experiments in C57Bl6 mice fed a high-fat diet corroborated our in vitro observations. Administration of pNaKtide in these mice reduced body weight gain, restored systemic redox and inflammatory milieu, and, crucially, improved insulin sensitivity. Thus, we propose that inhibition of Na/K-ATPase amplification of oxidative stress may ultimately be a novel way to combat obesity, insulin resistance, and metabolic syndrome. 

Retracted: No

PubPeer comments:
 ![file] Fig. 5A is the same as Fig. 5B, Fig. 5C is rotated by 180u00b0, which is the same as Fig. 5A and B , 
 ![file] Are Fig. 2B and Fig. 2C from the same PVDF membrane? , 
 SUPPLEMENTARY MATERIALS FIG S3B-FAS ![file] FIG S4C-MEST ![file] FIG S3B-FAS and FIG S4C-MEST are the same. , 
 It does look like a loading control may have inadvertently been missssigned. We will double check. Not sure I agree about the MEST and F AS blots. I will ask the first author. Dr. Sodhi, to organize all the blots used for this paper. I expect that we will still have all the computer images of the experimental and loading blots. , 
 #4 I agree with the concerns illustrated in #3. Examining the bands in inverse, some background features appear in both images, although the dimensions appear slightly different. Perhaps the original uncropped scan can address the concerns. *** ![file] *** **Funding** This work was supported by NIH grants HL109015 (to J.I.S. and Z.X.), HL071556 and HL105649 (to J.I.S.), and HL55601 and HL34300 (to N.G.A.); the Brickstreet Foundation (to J.I.S. and N.G.A.); and the Huntington Foundation Inc. Author contributions: K.S.: Designed and performed the experiments and wrote the manuscript. K.M.: Performed the experiments. Y.Y.: Performed the experiments. J.L.: Performed the experiments. M.A.C.: Performed the experiments. M.G.: Performed the experiments. Z.X.: Edited the manuscript and designed the experiments. N.G.A.: Conceived and designed the experiments and edited the manuscript. J.I.S.: Conceived and designed the experiments and wrote the manuscript. , 
 Thank you for pointing out these discrepancies. We would like to bring it to your notice that: 1.tThe MEST and FAS experimental blots are not identical as shown in the attached figures. Although visually the blots may seem similar, careful examination of uncropped, unedited blots shows several differences. 2.tThe loading control for the two similar blots were identical (FAS and MEST) because we cut the membrane and used loading control lane for both proteins 3.tThe other loading control does look like an inversion. It is possible that we mislabelled the image when we prepared for publication. When we review our original blots, the loading control image for that experimental blot was different . We have attached the correct loading control for that experiment and will revise this at the journal website. ![file] ![file] , 
 #6 Perhaps the authors could post a high resolution image here (or a link if the file is too large) to the **original uncropped scan**. To the point that one can find differences between the images: that is common even when the images are identical as they may have been processed differently or contain compression artifacts. I suggest that it is the *similarities* that are concerning. For now, I believe these two images share the same source. As suggested in #5, the original scan may reassure readers. , 
 Supplementary Materials pNaKtide inhibits Na K-ATPase reactive oxygen species amplification and attenuates adipogenesis Komal Sodhi, Kyle Maxwell, Yanling Yan, Jiang Liu, Muhammad A. Chaudhry, Morghan Getty, Zijian Xie, Nader G. Abraham, Joseph I. Shapiro DOI: 10.1126 sciadv.1500781 Figure S3, A (top panel) There appears to be overlap between the images for Control and  pNaKtide as indicated by the boxed regions. The aspect ratio differs between the two; one image appears to have been stretched or compressed horizontally and vertically. ![file] , 
 Thank you so much for posting out this mistake. We will find the raw files and will fix this issue. Thanks again. , 
 #9 Dr. Sodhi - Thank you for your reply. Two questions for you: 1. Were you able to locate the original uncropped scan for the issue first raised in comment #3? 2. Could you explain how the mistake illustrated in #8 could occur by chance? Wouldn t the altered dimensions suggest that this was done deliberately? , 
 It should also be explained how come some of the picture in Figure 4B also appeared in [Sodhi et al. 2009] Figures 1A and 4A. Figure 4B: ![file] [Sodhi et al. 2009] Figure 1A: ![file] [Sodhi et al. 2009] Figure 4A: ![file] , 
 Figure 3A. * Pink boxes: The  high fat mouse looks unexpectedly similar to the  pNaKtide 1 mg kg mouse. * Blue boxes: The  Control mouse looks unexpectedly similar to the  pNaKtide 25 mg kg mouse. ![file] , 
 There is now a correction with a new version of the Supplementary Materials (Adobe PDF - 1500781_SM_v2.pdf) on the journal web site. http: advances.sciencemag.org cgi content full 1 9 e1500781 DC1 Correction (22 April 2021): The authors corrected Figure 5C, which contained an incorrect blot for the actin loading control for the representative blot of adiponectin, and Supplementary Figure 3A where one of the representative images (control) was inadvertently taken from the Fr+pNaKtide group. So mistakes can happen. But how is it that the actin control in 5A was rotated 180 degrees when it was used for figure 5C? I would find an exact duplication less troubling. And how is it that the example shown in figure S3A had different parts of the slide image with the aspect ratio altered when it was mistakenly used twice? Mind you, it could happen, but still troubling. The correction does not address the following: Commentators #3 and #4 - FIG S3B-FAS and FIG S4C-MEST appear to be the same. Commentator #11 - the apparent duplication of images of tissues from an earlier publication. And, drum roll: Commentator #12 Elisabeth M. Bik - the parade of mice where some are u201cunexpectedly similaru201d? Would the authors care to comment? , 
 Here s a side-by-side comparison of the High fat and the pNaKtide 1 mg kg mice with circles to highlight the  seemingly identical features. I choose to call it  fingerprint analysis points to too many identical features that the images cannot represent different mice. ![file] , 
 https: www.science.org doi 10.1126 sciadv.adf3052 Editorial retraction H. Holden Thorp, Ali Shilatifard, and Philip Yeagle SCIENCE ADVANCES, 19 Oct 2022, Vol 8, Issue 42, DOI: 10.1126 sciadv.adf3052 After publication of DOI: 10.1126 sciadv.1500781 (pNaKtide inhibits Na K-ATPase reactive oxygen species amplification and attenuates adipogenesis), concerns were raised by readers about several of the figures in the paper. In response in 2020, two of the figures (5C and S3) were acknowledged by the authors to be incorrect and corrections were presented by the authors to Science Advances. In 2022, in response to continued criticism of figures in the paper, the authors acknowledged errors in Figure 4. The editors have further unresolved concerns about other figures. The editors have lost confidence in the integrity of the data presentation in this paper. As a consequence, the editors of Science Advances have decided to retract this paper. Drs. Shapiro and Abraham and Sodhi have not agreed with the retraction. The other authors were non-responsive. , 
 Retraction Watch coverage: [Former medical school dean earns sixth retraction]  *A kidney researcher and former dean of a medical school has now had six papers retracted and one marked with an expression of concern in a little more than a year.* *The latest retraction for Joseph I. Shapiro, of a 2015 paper in Science Advances, comes two years after PubPeer commenters began posting about potentially duplicated images in the article, and one year after the authors corrected two of its figures.* ,