NR AWSP
AU Bolea,R.; Lyahyai,J.; Serrano,C.; Monleon,E.; Moreno,C.; Osta,R.; Zaragoza,P.; Badiola,J.J.; Martin-Burriel,I.
TI Correlation between BAX overexpression and prion deposition in medulla oblongata from natural scrapie without evidence of apoptosis
QU European Society of Veterinary Pathology, 24th Meeting, Edinburgh, Scotland, 30.8.-2.9.2006, Session 5A: 88
IA http://www.esvp.eu/ESVP_meetings/Proceedings_2006.pdf
PT Oral presentation
AB Although apoptosis has been implicated in the neuronal loss observed in prion diseases, the participation of apoptosis related factors, like the Bcl-2 family of proteins, is still not clear. Moreover, there are conflicting data against the main role of apoptosis in the neuropathology associated with TSEs. Many studies have been developed in vitro or in experimentally infected animal models but, at present, little is known about this process in natural spontaneous and acquired prion diseases. In this work, the implication of Bax and Bcl-2 has been investigated through the analysis of their expression and protein distribution in medulla oblongata of naturally scrapie infected sheep. Moreover, their spatial relationship with PrPsc deposition, neuronal vacuolation and neuropile spongiosis has also been analysed and finally, the possible induction of neuronal apoptosis in this model. Real time RT-PCR showed an overexpression of the pro-apoptotic gene Bax in scrapie medullas and immunohistochemistry confirmed its accumulation. On the other hand, no variation was observed for Bcl-2 neither at transcript nor at protein level. Bax distribution, PrPsc deposition, neuronal vacuolation and spongiosis were quantified in different medulla oblongata nuclei and their spatial relationship was evaluated. Bax staining showed a positive correlation with prion deposition, suggesting that this factor is involved in prion neurotoxicity in our natural model. Despite Bax overexpression, neuronal apoptosis was neither revealed by TUNEL nor by immunohistochemical detection of the activated form of caspase-3. Absence of apoptosis in medulla oblongata of naturally scrapie infected sheep is in the process of being discussed.
AD Rosa Bolea, Jaber Lyahyai, Carmen Serrano, Eva Monleón, Carlos Moreno, Rosario Osta, Pilar Zaragoza, Juan J. Badiola, Inmaculada Martín-Burriel, University of Zaragoza, Spain
SP englisch
PO UK