Effect of carboxymethylated chitosan on the biosynthesis of NGF and activation of the Wnt/β-catenin signaling pathway in the proliferation of Schwann cells
Authors: Hao-Huan Li
Shi-Qing Liu
Hai-Ying Tao
Feng-Hua Tao
Qing Chen
Hai-Li Tao
Bin He
Wan-Xia Deng
Ai-Lin Wei
Journal: European journal of pharmacology (2013)
Discipline: PHARMACOLOGY & TOXICOLOGY
Keywords: Schwann cells; Wallerian degeneration; carboxymethylated chitosan (CMCS); nerve growth factor (NGF); Wingless-type (Wnt) protein
Affiliations: Department of Orthopedics, Renmin Hospital of Wuhan University, 238 Jiefang Road, Wuchang District, Wuhan 430060, Hubei Province, People's Republic of China.

Abstract:  The proliferation of Schwann cells around injured peripheral nerves supports the process of Wallerian degeneration and is critical for axonal regeneration. In this publication, carboxymethylated chitosan (CMCS) was studied to determine its capacity (i) to induce proliferation and secretion of nerve growth factor (NGF) and (ii) to activate Wingless-type(Wnt) protein/β-catenin signaling pathways in rat Schwann cells. CMCS was found to induce Schwann cell proliferation and NGF synthesis in Schwann cell in a dose and time dependent manner. CMCS was shown to activate factors in the Wnt/β-catenin signaling pathway, including Dvl-1, β-catenin, Tcf4, Lef1, C-myc, and Cyclin D1 which are active in the proliferation of Schwann cells and biosynthesis of NGF of Schwann cell. Overall, this study suggests that CMCS can promote the proliferation of cultured Schwann cells and synthesis of NGF by activating the Wnt/β-catenin signaling pathway. 

Retracted: No

PubPeer comments:
 All five panels in Figures 5B and 6A appear to look similar to panels in Figures 4 and 5 of an older paper by the same authors, i.e. Bin He et al., European Journal of Pharmacology 667 (2011) 195u2013201, DOI: 10.1016 j.ejphar.2011.06.001. Panels that look similar are shown with boxes and arrows of the same color, where the arrows show the orientation of the panels. Of note, panels represent different proteins and experiments, and are sometimes shown in mirror image. ![file] , 
 Thank you for pointing this out, Elisabeth. We will go after this. Frank Redegeld, EiC, European J Pharmacol , 
 Dear Elisabeth Thank you for your interest in our research and your efforts to ensure the accuracy of scientific research. Regarding your comments on Figures 5B and 6A in EJP-2013 (702:85-92)and Figures 4 and 5 in EJP-2011( 667:195u2013201), there were indeed the similar patterns. After receiving your query, we carefully checked our original data and experimental records, its really the different bands in the raw data. These mistakes probably due to the carelessness in later data processing. Improper images were used due to our unintentional errors. We also failed to discover the problems during the submission process. Under no circumstances will we intentionally falsify and tamper with experimental data to mislead reviewers and readers. We are so sorry about the lack of rigour or negligence. We will contact the editor of the journal to resubmit the correct images. We will take this lesson as a valuable learning opportunity to do better in the future research work. Thanks again! Yours sincerely, Bin He , 
 Dear Elisabeth Thank you for your interest in our research and your efforts to ensure the accuracy of scientific research. Regarding your comments on Figures 5B and 6A in EJP-2013 (702:85-92)and Figures 4 and 5 in EJP-2011( 667:195u2013201), there were indeed the similar patterns. After receiving your query, we carefully checked our original data and experimental records, its really the different bands in the raw data. These mistakes probably due to the carelessness in later data processing. Improper images were used due to our unintentional errors. We also failed to discover the problems during the submission process. Under no circumstances will we intentionally falsify and tamper with experimental data to mislead reviewers and readers. We are so sorry about the lack of rigour or negligence. We will contact the editor of the journal to resubmit the correct images. We will take this lesson as a valuable learning opportunity to do better in the future research work. Thanks again! Yours sincerely, Bin He , 
 Dear Elisabeth Thank you for your interest in our research and your efforts to ensure the accuracy of scientific research. Regarding your comments on Figures 5B and 6A in EJP-2013 (702:85-92)and Figures 4 and 5 in EJP-2011( 667:195u2013201), there were indeed the similar patterns. After receiving your query, we carefully checked our original data and experimental records, its really the different bands in the raw data. These mistakes probably due to the carelessness in later data processing. Improper images were used due to our unintentional errors. We also failed to discover the problems during the submission process. Under no circumstances will we intentionally falsify and tamper with experimental data to mislead reviewers and readers. We are so sorry about the lack of rigour or negligence. We will contact the editor of the journal to resubmit the correct images. We will take this lesson as a valuable learning opportunity to do better in the future research work. Thanks again! Yours sincerely, Bin He , 
 Dear Frank, We are so sorry for these mistakes. these two articles published in EJP-2011 and EJP-2013 were a series of studies on the application of Carboxymethylated chitosan in Schwann cell proliferation, these studies were finished almost in the same time. We have carefully checked out the original data and experimental records, its really the different results and figures in the raw data. These mistakes probably due to the carelessness in later data processing, and we also failed to discover the problems during the submission process. Under no circumstances will we intentionally falsify and tamper with experimental data to mislead reviewers and readers. We are so sorry about the lack of rigour or negligence. May we resubmit the correct figures to replace the incorrect figures? We are so sorry to couse you so much trouble. Yours sincerely, Bin He , 
 #6 Please contact us via the editorial office of EJP: ejp-office@uu.nl ,