Propofol improved neurobehavioral outcome of cerebral ischemia–reperfusion rats by regulating Bcl-2 and Bax expression
Authors: Xiao-Guang Cui
Zi-Yong Yue
Tao Tao
Tian-Hua Zhang
Chun-Yu Song
Shu-Jun Lu
Hong-Jie Xi
Journal: Brain Research (2011)
Discipline: NEUROSCIENCE & BEHAVIOR
Keywords: Propofol; neuroprotective effects; cerebral ischemia-reperfusion injury; apoptosis; Bcl-2
Affiliations: Department of Anesthesiology, China and Heilongjiang Key Laboratory for Anesthesia and Critical Care, The Second Affiliated Hospital of Harbin Medical University, Harbin 150081, China.

Abstract:  Propofol is an intravenous anesthetic with neuroprotective effects against cerebral ischemia-reperfusion (I/R) injury. Few studies regarding the neuroprotective and neurobehavioral effects of propofol have been conducted, and the underlying mechanisms are still unclear. Because I/R may result in neuronal apoptosis, the apoptosis regulatory genes B-cell leukemia-2 (Bcl-2) and Bcl-2-associated X protein (Bax) may be involved in the neuroprotective process. In this study, 120 Wistar rats were randomly divided into three groups (sham, I/R-induced, and propofol-treated). Cerebral ischemia was induced by clamping the bilateral common carotid arteries for 10min. Propofol (1.0mg/kg/min) was administered intravenously for 1h before the induction of ischemia. Neuronal damage was evaluated by neurobehavioral scores and histological examination of the brain sections at the level of the dorsal hippocampus at 6h, 24h, 48h, 72h, 4days, 5days, 6days, and 7days after I/R. The apoptotic rate of hippocampal neurons was detected by flow cytometry. The expression of Bcl-2 and Bax was evaluated using immunohistochemical and Western blot methods. The results of this study showed that neurobehavioral scores were higher in propofol-treated rats compared with I/R-induced rats with no propofol treatment. Moreover, the hippocampal expression of Bcl-2 was significantly higher, while the expression of Bax was significantly lower in propofol-treated rats compared with I/R-induced rats at 24h after ischemia. Hence, this study suggests that the neuroprotective effects of propofol against neuronal apoptosis may be a consequence of the regulation of Bcl-2 and Bax. 

Retracted: No

PubPeer comments:
 Panels A and E in figure 2 of this paper are identical, and panel B is also clearly from the same slide. Can the authors explain how this has occurred? ![file] , 
 Dear editor Thank you for your letter. Doctor song has reply this letter. I agree with her. Thanks again. , 
 #1 Dear Editor: Thanks a lot for your error correction. Panels A and E in Figure 2 in this paper were the same pictures. I am so sorry for this mistake. I could provide the correct picture for Panel E in Figure 2, which is correspond to Panels J also. Panels B was not from the same slide. Panels B was from another slide in ischemia group. Panels A, B and E have the same oil stain because of the dirty microscope and we take the pictures in the same day. Thanks again for your correction ! ![file] , 
 Dear Author, Panel B looks like the same slide as Panel A and E, but that the microscope has moved. I have copied image B and superimposed it on Panels A and E. I have then applied a subtraction blending mode whereby if the pixels are the same the image becomes black. To my eye, it looks like it is the same slide with the difference being that the dust spot have moved and the edge of the image isn t exactly the same (possibly due to lens distortion). Can the Authors please explain this similarity? ![file] ![file] , 
 #4 Dear professor Sanchia S. Smith: Thank you for your correction. Our team check all the initial data immediately after we received your comment. We are so sorry for our mistakes because a lot of images and data should be treated. Now, we should provide the right images (orginal images) for you! Thank you very much for correction again! ![file] ![file] ![file] ![file] ![file] , 
 #4 Dear professor Sanchia S. Smith, Because of the file size limitation, we upload other original images here! Thank you again! ![file] ![file] ![file] ![file] ![file] , 
 #2 The new image supplied in your first response was to my question was, I think you were saying, supposed to be the correct one for panel E, but it appears to be the same as panel D from the published paper and also from your later response here, only it is less magnified and rotated 180 degrees. Is that correct? , 
 Dear Author, From the new images you have uploaded, it appears that Images D and E are of the same slide, but rotated 180 degrees. I have superimposed image D onto E and applied a subtraction mask again. ![file] ![file] , 
 #8 #7 Dear professor John A Loadsman, professor Trichoderma Parestonicum, Thank you for your comments. We have revised all the raw data of this experiment. We just focus on the image A and E in last reply, but we ignore the other images. We sincerely apologize for the mistake of last upload. You are right, and we all agree with your comment. The correct image D and I are attached below. We are so sorry for our mistake and thanks again. ![file] ![file] ,