RETRACTED ARTICLE: Chondro-protective effects of polydatin in osteoarthritisthrough its effect on restoring dysregulated autophagy via modulating MAPK, and PI3K/Aktsignaling pathways
Authors: Zhiwei Luan
Wenyu Feng
Kai Zou
Jun Yao
Xiaohan Zhang
Mingwei He
Zhengyuan Wu
Shiting Ma
Linhua Jiang
Jia Li
Zhenyi Yang
Journal: Scientific Reports (2019)
Discipline: Multidisciplinary
Keywords: Osteoarthritis; Polydatin; Anti-inflammatory; Anti-arthritic potential; Therapeutic properties
Affiliations: Department of Orthopaedics Trauma and Hand Surgery, The First Affiliated Hospital of Guangxi Medical University, Nanning, 530021, China., Guangxi Collaborative Innovation Center for Biomedicine, Life Sciences Institute, Guangxi Medical University, Nanning, 530021, China., Departments of Pathology, The First Affliated Hospital of Guangxi Medical University, Nanning, 530021, China. ., Department of Bone and Joint Surgery, The First Affiliated Hospital of Guangxi Medical University, Nanning, 530021, China. ., Guangxi Collaborative Innovation Center for Biomedicine, Life Sciences Institute, Guangxi Medical University, Nanning, 530021, China. .

Abstract:  Osteoarthritis (OA) is a degenerative disease of the cartilage that is prevalent in the middle-aged and elderly demography. Polydatin (PD), a natural resveratrol glucoside, has shown significant anti-inflammatory and anti-arthritic potential in previous studies. This study was designed to evaluate the therapeutic properties of PD in vitro and in vivo, and elucidate their underlying mechanisms. The expression levels of all relevant factors were evaluated by qRT-PCR, western blotting, and immunohistochemistry (IHC) where suitable. Reactive oxygen species (ROS) and apoptosis were analyzed using the suitable probes and flow cytometry. The histological evidence of cartilage was assessed in rat models, moreover, the several serum cytokines levels and autophagy levels were evaluated. The result showed PD displayed significant chondro-protective effects, inferred in terms of reduced inflammation and cartilage degradation, apoptosis inhibition, and lower ROS production. The protective effects were attenuated by the autophagy inhibitor 3-MA, indicating a mediating role of autophagy in PD action. Mechanistically, PD exerted its effects by inhibiting the MAPK and PI3K/Akt signaling pathways which led to the down-regulation of mTOR. In conclusion, PD protects against cartilage degeneration by activating the autophagy flux in the chondrocytes via the MAPK and PI3K/Akt signaling pathways. 

Retracted: Yes

PubPeer comments:
 One part of the Figure 4a of this paper has an unexpected similarity to part of the Figure 2a of another paper from the same authors, Wu, et al. J Cell Physiol. 2019;1-13 The two photos look like from the same femoral condyle but having different camera viewing angles. Experiments in these 2 papers were on different treatments to the knee joint of the animals, and these two images were not from the control group. ![file] ![file] , 
 Thank you very much for discovering this problem. We also found the image usage error a few weeks ago, because our software layout caused the image to be used incorrectly when the image was last submitted. At the same time, we have submitted a revised request to the magazine a few days ago. , 
 There is only one possible explanation, and it s human: FxxxD , 
 More problematic issues with Figure 2A: There are two additional micrographs which are surprisingly similar to micrographs published in another article (Wu Z et al., 2019; J Cell Physiology). One of them have been modified by stretching or compression. There is an urgent need for quality control in scientific publications. If it continues like this, we risk that scholarly medicine will be comparable to alternative medicine or chinese traditional medicine. No trust left! ![file] , 
 #3 #Clear chinese authors fake scientific papers to avoid contaminating the real science. , 
 One part of the Figure 4i and 4h of this paper has an unexpected similarity to part of the Figure 4a of another paper from the same authors, Wu, et al. J Cell Physiol. 2019;1-13 These two pictures look like the same picture. But the authors labeled different stained antibodies. , 
 One part of the Figure 4i and 4h of this paper has an unexpected similarity to part of the Figure 4a of another paper from the same authors, Wu, et al. J Cell Physiol. 2019;1-13 These two pictures look like the same picture. But the authors labeled different stained antibodies. ![file] , 
 #6  One part of the Figure 4i and 4h of this paper has an unexpected similarity to part of the Figure 4a of another paper from the same authors Figs 4 h i j: ![] Fig 4a from [Wu et al (2019)] : ![file] I count three re-used panels though two of them are labelled consistently for treatment, duration and antibody. , 
 Retraction of: Scientific Reports https: doi.org 10.1038 s41598-019-50471-y , published online 25 September 2019 https: www.nature.com articles s41598-020-68880-9  The Authors have retracted this Article. After publication concerns were raised with respect to duplication of panels in Figure 4 with those in Figures 2 and 4 of another article by the same authors1. When reviewing their data files for this figure the Authors noticed problems with the data presented in other figures in their article but were unable to locate the original data files. All Authors agree with this retraction. ,