6-Hydroxydopamine activates the mitochondrial apoptosis pathway through p38 MAPK-mediated, p53-independent activation of Bax and PUMA
Authors: Joan X Comella
Joaquin Jordan
Miguel F Segura
Nuria Llecha
Francisco J Fernandez-Gomez
Jochen H M Prehn
Maria Gomez-Lazaro
Caoimhín G Concannon
Maria F Galindo
Journal: Journal of Neurochemistry (2008)
Discipline: NEUROSCIENCE & BEHAVIOR
Keywords: Mitochondrial alterations; 6-hydroxydopamine; Parkinson's disease; mitochondrial membrane permeability; cytochrome c release
Affiliations: Grupo de Neurofarmacología, Departamento de Ciencias Médicas, Facultad de Medicina, Universidad Castilla-La Mancha, Albacete, Spain.

Abstract:  Mitochondrial alterations have been associated with the cytotoxic effect of 6-hydroxydopamine (6-OHDA), a widely used toxin to study Parkinson's disease. In previous work, we have demonstrated that 6-OHDA increases mitochondrial membrane permeability leading to cytochrome c release, but the precise mechanisms involved in this process remain unknown. Herein we studied the mechanism of increased mitochondrial permeability of SH-SY5Y neuroblastoma cells in response to 6-OHDA. Cytochrome c release induced by 6-OHDA occurred, in both SH-SY5Y cells and primary cultures, in the absence of mitochondrial swelling or a decrease in mitochondrial calcein fluorescence, suggesting little involvement of the mitochondrial permeability transition pore in this process. In contrast, 6-OHDA-induced cell death was associated with a significant translocation of the pro-apoptotic Bax protein from the cytosol to mitochondria and with a significant induction of the BH3-only protein PUMA. Experiments in mouse embryonic fibroblasts deficient in Bax or PUMA demonstrated a role for both proteins in 6-OHDA-induced apoptosis. Although 6-OHDA elevated both total and nuclear p53 protein levels, activation of p53 was not essential for subsequent cell death. In contrast, we found that p38 mitogen-activated protein kinase (MAPK) was activated early during 6-OHDA-induced apoptosis, and that treatment with the p38 MAPK inhibitor SKF86002 potently inhibited PUMA induction, green fluorescent protein-Bax redistribution and apoptosis in response to 6-OHDA. These data demonstrate a critical involvement of p38 MAPK, PUMA, and Bax in 6-OHDA-induced apoptosis. 

Retracted: No

PubPeer comments:
 Apparently there is a cabal of antiscientists currently active on PubPeer dedicated to undermining the pure science and the even purer motives of some outfit in Marseilles. Itu2019s been hampering their efforts to dose up COVID patients with HCQ. That is just so unfair. https: www.buzzfeednews.com article stephaniemlee elisabeth-bik-didier-raoult-hydroxychloroquine-study The intarwebs being what it is, the tweetosphere has inevitably plunged into the depths of a seemingly bottomless well of ordure. Trolls gotta troll. Aroused by all this hullaballoo, I couldnu2019t help but wonder whether the gel in Fig. 1 of this 2000 paper has been manipulated and republished a year later. https: pubpeer.com publications ED2EE34263553661AC8BCEBAED03AC The vertical artefacts in some of the lanes match up well. However, the whole gel cannot be superposed, in part due to internal splicing between some lanes. Vertically stretched, rotated and differently cropped it maybe too. Some lanes may have been flipped and repasted in position. Some lanes may have vertical smearing effects. Three additional lanes are also newly added at right. It is going to take lane-by-lane transparency superpositions to work through the similarities. May as well begin with lanes 10. ![image] Dr. Condy has been labouring under the misapprehension that new papers are supposed to have new data. Perhaps that is why it has not yet injected 3,168 publications into the scientific literature. Still, it is never too late to learn from oneu2019s peers out there. , 
 Next up the lanes 5 are superposed. Lanes 3 and 4 are shifted horizontally. Lane 6 in 2021 is not lane 6 in 2020 - weu2019ll come back to that later. ![image] , 
 It turns out that the 2020 Fig. 1 WB has already been reused in its entirety. Back in 2020. The same year it was first published. Unacknowledged. This observation may be appreciated at https: pubpeer.com publications 645E9E294197B90ED341981E263156 Regarding efforts at lane superpositioning, perhaps it might be better to invert greyscale for both WB images and then use RGB colour overlay as an estimate of band similarity. If one gel is now blue and the other is green, and one of them is 50% transparent, then the goal is to maximise what approximates as cyan. In this case for superposed lanes 3. Bearing in mind that Dr. Condy is a woody Amazonian plant that absorbs blue light but prefers to reflect green wavelengths, how did it manage? ![image] , 
 Since my last lane superpositioning effort, things seem to have all gone a bit pear-shaped down Marseillesu2019 way. https: www.leparisien.fr societe sante didier-raoult-accuse-davoir-falsifie-des-resultats-de-tests-pour-ses-travaux-lhopital-ouvre-une-enquete-interne-19-11-2021-XPFMQ52W75C67CYHNOHYL7TEBY.php *u201cPlus u00e7a change, plus c est la mu00eame choseu201d* Might the French establishment now get around to reviewing the way that u201cla recherche scientifiqueu201d has recently been conducted in that institutional mini-dictatorship? *u201cu00c0 la recherche du COVID-19 temps perduu201d* Optimist that I am, I hope to sign off on the admittedly rather more dull stuff here with this Lanes 1 superposition. That required a 2u00ba Rotation and the usual stretchiness. The temporally subsequent WB is inverted and set to 100% green colour channel. The original WB is inverted and set to 100% for both red and blue channels. Superposed elements should approximate to grey white. ![image] ,