Paeoniflorin inhibits nucleus pulposus cell apoptosis by regulating the expression of Bcl-2 family proteins and caspase-9 in a rabbit model of intervertebral disc degeneration
Authors: Honglin Teng
Yusen Dai
Kelun Huang
Jing Wang
B I Chen
Lijun Shi
Chi Li
Minyu Zhu
Journal: Experimental and therapeutic medicine (2015)
Discipline: CLINICAL MEDICINE
Keywords: Bax; Bcl-2; cell apoptosis; intervertebral disc degeneration; paeoniflorin.
Affiliations: Department of Pharmacy, The First Affiliated Hospital of Wengzhou Medical University, Wenzhou, Zhejiang 325000, P.R. China., Department of Orthopedics, The First Affiliated Hospital of Wengzhou Medical University, Wenzhou, Zhejiang 325000, P.R. China.

Abstract:  Apoptosis plays a key role in the pathogenesis of internal disc disruption (IDD); therefore, the inhibition of apoptosis may offer a novel approach for treating IDD diseases. The aim of the present study was to investigate the effects and the underlying mechanisms of paeoniflorin through the detection of relevant indicators in a rabbit model of IDD. In total, 144 rabbits were used in the study and divided into four groups (n=36 per group). Rabbits successfully modeled with IDD received an intragastric injection of 120 mg/kg·day paeoniflorin (high-dose group), 30 mg/kg·day paeoniflorin (low-dose group) or saline (model saline group), while rabbits without IDD were used as a normal control group. The apoptosis rate of disc nucleus pulposus cells was detected using flow cytometry. In addition, the expression levels of Bcl-2, Bax and caspase-9 in the disc tissues were detected using immunohistochemistry and western blot analysis prior to and following the treatment. The results indicated that the expression levels of Bax in the low- and high-dose paeoniflorin groups were significantly reduced, while the Bcl-2 expression levels were significantly increased when compared with the model saline group (P&lt;0.01). In addition, the expression levels of cleaved caspase-3 and cleaved caspase-9 were reduced in the low- and high-dose paeoniflorin groups, as compared with the model saline group (P&lt;0.05). Furthermore, the average apoptotic index of the high- and low-dose paeoniflorin groups was decreased when compared with the model saline group (P&lt;0.05). In conclusion, paeoniflorin was demonstrated to inhibit the apoptosis of nucleus pulposus cells and the activation of caspase-3 and caspase-9 through the regulation of Bcl-2 family protein expression. These results provide an experimental basis for the future treatment of IDD with paeoniflorin. 

Retracted: No

PubPeer comments:
 This paper was found during a systematic search of papers in this journal with possible duplicated images. About 10% of the papers in this journal (n=169 examined) were found to contain inappropriately duplicated images. These papers have all been reported to the journal publisher in 2017. The editors promised to  investigate promptly but no action has been taken as of today. Figure 3 in this paper shows 3 panels that appear to contain repetitive elements. Boxes of the same color draw attention to areas that look similar. In addition, these flow cytometry panels also look remarkably similar to panels in a 2013 paper by a completely different group (different institute, different city, different authors). That paper is:  Human Leptin Protein Induces Proliferation of A549 Cells via Inhibition of PKR-Like ER Kinase and Activating Transcription Factor-6 Mediated Apoptosis - Qun Lai and Yan Sun - Yonsei Med J 54(6):1407-1415, 2013 - DOI: 10.3349 ymj.2013.54.6.1407 ![file] ,