Retracted Article: Ligustrazine attenuates renal damage by inhibiting endoplasmic reticulum stress in diabetic nephropathy by inactivating MAPK pathways
Authors: Shukun Wu
Hongling Yang
Journal: RSC Advances (2018)
Discipline: CHEMISTRY
Keywords: Diabetic nephropathy; Endoplasmic reticulum stress; Ligustrazine; Treatment; Streptozotocin
Affiliations: Department of Nephrology, Sichuan Academy of Medical Sciences & Sichuan Provincial People's Hospital, Chengdu, China, Chinese Academy of Sciences Sichuan Translational Medicine Research Hospital

Abstract:  Background: Diabetic nephropathy (DN) is a major cause of chronic kidney disease around the world. Endoplasmic reticulum (ER) stress plays an important role in DN progression. Ligustrazine (Lig) is derived from the Chinese herb Ligusticum wallichii and is reported to exert anti-oxidant, anti-inflammation and anti-fibrosis effects. The aim of our study was to investigate the influence of Lig on the treatment of DN. Methods: Streptozotocin (STZ) was used to induce diabetes in Sprague-Dawley (SD) rats. Then, STZ-induced rats were treated with different concentrations of Lig (50 or 150 mg kg-1 day-1) for 8 weeks of treatment. Urinary albumin concentrations, blood urea nitrogen (BUN), serum creatinine (Scr) and creatinine clearance (Ccr) were determined. The levels of proinflammatory cytokines (IL-8, IL-6, IL-1β and TNF-α) were estimated by ELISA. TUNEL assay was used for apoptosis index measurement. Western blot was used for the detection of GRP78, CHOP, p-eIF2α, eIF2α, p-p38, p-38, p-ERK1/2 and ERK1/2. Results: Lig treatment significantly reduced urinary albumin excretion, BUN and Scr and increased Ccr in STZ-induced rats. Lig also suppressed the levels of IL-8, IL-6, IL-1β and TNF-α and inhibited apoptosis dose-dependently. In addition, Lig inhibited GRP78 and CHOP expression and prevented the phosphorylation of eIF2α, p-38 and ERK1/2. Conclusion: Our study indicated that Lig attenuated renal damage by inhibiting ER stress in DN by inactivating MAPK pathways. 

Retracted: Yes

PubPeer comments:
 Retracted [7 January 2021] . ------------------------------------------- The Royal Society of Chemistry hereby wholly retracts this RSC Advances article due to concerns with the reliability of the data. The images in the article were screened by an image integrity expert who confirmed that some of the western blot images in this paper had been duplicated in other articles. There are no common authors between the papers. The control bands (GAPDH) in Fig. 3A of this paper are identical to the western blot control bands (GAPDH) presented in Fig. 1E of ref. 1. The control bands (GAPDH) in Fig. 4A of this paper are identical to the western blot control bands (GAPDH) presented in Fig. 2C and Fig. 4G of ref. 2. One of the blots in the control band (GAPDH) in Fig. 4A has also been reused as a blot in Fig. 3D of ref. 3. The authors were asked to provide the raw data for this article but did not respond. Given the significance of the concerns about the validity of the data, and the lack of raw data, the findings presented in this paper are not reliable. The authors have been informed but have not responded to any correspondence regarding the retraction. Signed: Laura Fisher, Executive Editor, RSC Advances. Date: 7th January 2021. References Ci Li , W. Wu , G. Jiao , Y. Chen and H. Liu , RSC Adv., 2018, 8 , 20202 u201420210 RSC . Z. Tang , L. Yang and X. Zhang , RSC Adv., 2017, 7 , 56406 u201456416 RSC . B. Zhu , X. Wang and J. Teng , RSC Adv., 2018, 8 , 36422 u201436429 RSC . ------------------------------------------------------- Indeed, the WBs are distinctive in style, resembling processionary caterpillars drawn on a periodic textured background. Fig 4A: ![file] Some caterpillars are surrounded by the sharp letterbox edges of copy-paste. ![file] I am commenting on this paper (despite its retraction) because the same style is familiar from other papers, not retracted. Here, for instance, Fig 2F from [Li, Liu Fu (2018)] . ![] Fig 3D of [Chen et al (2018)] : ![] Other examples are listed in a Google spreadsheet: https: docs.google.com spreadsheets d 19wUtpXazLg2zKbTpDBuq0smG6-A7VHYifkieoyyuTcQ edit#gid=0 ,