Activation of the phagocyte NADPH oxidase/NOX2 and myeloperoxidase in the mouse brain during pilocarpine-induced temporal lobe epilepsy and inhibition by ketamine
Authors: Fatma Tannich
Ouajdi Souilem
Bruno Eto
Amina Chniguir
Pham My-Chan Dang
Jamel El-Benna
Asma Tlili
Coralie Pintard
Journal: Inflammopharmacology (2020)
Discipline: PHARMACOLOGY & TOXICOLOGY
Keywords: Epilepsy; Ketamine; Myeloperoxidase; NOX2; Neuro-Inflammation
Affiliations: Laboratory of Physiology and Pharmacology, National School of Veterinary Medicine, University of Manouba, Sidi Thabet, Tunisia. ., Neurophysiology Laboratory and Functional Pathology, Department of Biological Sciences, Faculty of Sciences of Tunis, University Campus of Al-Manar, Tunis, Tunisia. ., INSERM U1149, ERL 8252 CNRS, Centre de Recherche sur l'Inflammation, Université Paris Diderot, Sorbonne Paris Cité, Laboratoire d'Excellence Inflamex, Faculté de Médecine, Site Xavier Bichat, 16 rue Henri Huchard, 75018, Paris, France. ., INSERM U1149, ERL 8252 CNRS, Centre de Recherche sur l'Inflammation, Université Paris Diderot, Sorbonne Paris Cité, Laboratoire d'Excellence Inflamex, Faculté de Médecine, Site Xavier Bichat, 16 rue Henri Huchard, 75018, Paris, France., Laboratoires TBC, Faculty of Pharmaceutical and Biological Sciences, 59006, Lille, France., Laboratory of Physiology and Pharmacology, National School of Veterinary Medicine, University of Manouba, Sidi Thabet, Tunisia.

Abstract:  Excessive reactive oxygen species (ROS) production can induce tissue injury involved in a variety of neurodegenerative disorders such as neurodegeneration observed in pilocarpine-induced temporal lobe epilepsy. Ketamine, a noncompetitive N-methyl-D-aspartate (NMDA) receptor antagonist has beneficial effects in pilocarpine-induced temporal lobe epilepsy, when administered within minutes of seizure to avoid the harmful neurological lesions induced by pilocarpine. However, the enzymes involved in ROS productions and the effect of ketamine on this process remain less documented. Here we show that during pilocarpine-induced epilepsy in mice, the expression of the phagocyte NADPH oxidase NOX2 subunits (NOX2/gp91phox, p22phox, and p47phox) and the expression of myeloperoxidase (MPO) were dramatically increased in mice brain treated with pilocarpine. Interestingly, treatment of mice with ketamine before or after pilocarpine administration decreased this process, mainly when injected before pilocarpine. Finally, our results showed that pilocarpine induced p47phox phosphorylation and H2O2 production in mice brain and ketamine was able to inhibit these processes. Our results show that pilocarpine induced NOX2 activation to produce ROS in mice brain and that administration of ketamine before or after the induction of temporal lobe epilepsy by pilocarpine inhibited this activation in mice brain. These results suggest a key role of the phagocyte NADPH oxidase NOX2 and MPO in epilepsy and identify a novel effect of ketamine. 

Retracted: No

PubPeer comments:
 P47phox Western blot bands were duplicated in Fig. 2A and 3A: ![file] , 
 There appears to be a differential splice in figure 2a. Could the authors please post the original uncropped scans? *** Inverse image ![file] *** Original ![file] , 
 Dear Colleague, Indeed the blot of p22phox was done on 2 gels run at the same time, three samples were analysed on one gel and the other two samples on an other gel. I m sending you here the raw images as developed by the camera. The figure were not changed or modified.![file] The red MW band is 25kDa and the blue band is 20 kDa. Also regarding your former comment on the p47phox blot duplication in Figure 2 and 3 of the same manuscript, we sent a new figure to the journal with new p47phox blot and the journal accepted this correction. The correction is in preparation. I ensure you that, in the future we will be more carefull to check all images, figures and experiments to ensure compliance with good practice to carefully monitor publications with my colleagues. We sincerely apologize for these non-intentional figure problems occured during figure preparation. Yours sincerely, Jamel El Benna. , 
 #3 Thank you for your reply. You may wish to consult with the journal about whether the splice in Figure 2a has been properly disclosed as published. It appears that the merged image was edited to make the splice difficult to identify. Most journals frown on this type of image manipulation. As to the prior comment, it appears to have been made by another anonymous reader, but removed by the moderators for an unknown reason. , 
 Correction Published: 04 January 2021  We regret that in the original article, the same p47phox western blot was used in Figure 2(a) and Figure 3(a). Actually, the same mice brain extracts were used in both figures, and we thought it was more accurate to check whether in the same mice brain extracts used in Figure 2a, p47phox was also phosphorylated as shown in Figure 3a. In the corrected version of Fig. 3, we have now used new mice brain extracts to provide new western blots of p47phox, phospho-Ser315, phosphor-Ser328 and new statistics. We apologize for any convenience caused by this duplication. ![file] , 
 Dear Colleagues, I would like to Thank you for bringing to our attention these figures problem, after your messages, the journal asked us to provide a new figure, which was published in a correction to the article. Thank you again, Sincerely, Pr. Jamel El Benna. ,