Reduced levels of reactive oxygen species correlate with inhibition of apoptosis, rise in thioredoxin expression and increased bovine leukemia virus proviral loads.
BACKGROUND
Bovine Leukemia virus (BLV) is a deltaretrovirus that induces lymphoproliferation and leukemia in ruminants. In ex vivo cultures of B lymphocytes isolated from BLV-infected sheep show that spontaneous apoptosis is reduced. Here, we investigated the involvement of reactive oxygen species (ROS) in this process.


RESULTS
We demonstrate that (i) the levels of ROS and a major product of oxidative stress (8-OHdG) are reduced, while the thioredoxin antioxidant protein is highly expressed in BLV-infected B lymphocytes, (ii) induction of ROS by valproate (VPA) is pro-apoptotic, (iii) inversely, the scavenging of ROS with N-acetylcysteine inhibits apoptosis, and finally (iv) the levels of ROS inversely correlate with the proviral loads.


CONCLUSIONS
Together, these observations underline the importance of ROS in the mechanisms of inhibition of apoptosis linked to BLV infection.
Bouzar
Amel Baya
AB
Université de Liège (ULg), Gembloux Agro-Bio Tech, Molecular and Cellular Biology, Gembloux, Belgium. bouzar.a@fsagx.ac.be
Boxus
Mathieu
M
Florins
Arnaud
A
François
Carole
C
Reichert
Michal
M
Willems
Luc
L
D000818:Animals; D017209:Apoptosis; D001402:B-Lymphocytes / Q000821:virology*; D002478:Cells, Cultured; D001909:Leukemia Virus, Bovine / Q000254:growth & development / Q000276:immunology*; D011533:Proviruses / Q000254:growth & development / Q000276:immunology*; D017382:Reactive Oxygen Species / Q000276:immunology*; D012756:Sheep; D013879:Thioredoxins / Q000096:biosynthesis*
D017382:Reactive Oxygen Species; D013879:Thioredoxins