Proteasome inhibition: an early or late event in nitric oxide-induced neuronal death?

Peng, Z. F., Chen, M. J., Yap, Y. W., Manikandan, J., Melendez, A. J., Choy, M. S., Moore, P. K. and Cheung, N. S. (2008) Proteasome inhibition: an early or late event in nitric oxide-induced neuronal death? Nitric Oxide, 18(2), pp. 136-145. (doi: 10.1016/j.niox.2007.11.002)

Full text not currently available from Enlighten.

Publisher's URL: http://dx.doi.org/10.1016/j.niox.2007.11.002

Abstract

Nitricoxide (NO), ubiquitously expressed in the central nervous system, has been perceived to be a potential neuromodulator. Employing cultured murine primary cortical neurons, NO resulted in an inhibition of the ubiquitin–proteasome system (UPS) with a dose- and time-dependent decrease in cell viability. This is consistent with a previous study that reported a dysfunction of UPS with consequential apoptotic death in macrophage cell with NO treatment. However, it cannot be unclear if the drop in UPS efficiency is directly imposed on by NO. Therefore by using microarray analysis, our study revealed an early down-regulation or non-significant differential expression of genes encoding UPS proteins in NOC-18 (NO donor)-treated neurons as compared to an observed elevation of corresponding gene expression genes in lactacystin (classical proteasome inhibitor)-treated neurons (conducted earlier). Furthermore, time-course analysis of proteasome activity in NOC-18-treated neurons demonstrated a late onset of reduction. This is intriguing as it is well established that in an exclusive proteasome dysfunction-induced cell death, a compensatory feedback mechanism will be activated with an initial and concerted up-regulation of genes encoding proteins involved in UPS as seen when neurons were treated with lactacystin. Thus, it is highly suggestive that NO-triggered neuronal death takes on a different signaling cascade from that of a classical proteasome inhibitor, and that the late reduction of proteasome activity is a downstream event following the activation of apoptotic cellular signaling cascade. In intracellular condition, the proteasome is not NO preferred primary target responsible for the trigger of the cell death machinery. In conclusion, we presented novel findings that shed light into NO-induced cell death signaling cascade, which would be important in understanding the pathogenesis of neurodegenerative disorders such as Parkinson’s disease.

Item Type:Articles
Status:Published
Refereed:Yes
Glasgow Author(s) Enlighten ID:Melendez Romero, Dr Alirio
Authors: Peng, Z. F., Chen, M. J., Yap, Y. W., Manikandan, J., Melendez, A. J., Choy, M. S., Moore, P. K., and Cheung, N. S.
College/School:College of Medical Veterinary and Life Sciences > School of Infection & Immunity
Journal Name:Nitric Oxide
Publisher:Academic Press
ISSN:1089-8603
ISSN (Online):1089-8611
Published Online:22 November 2007
Related URLs:

University Staff: Request a correction | Enlighten Editors: Update this record

Project CodeAward NoProject NamePrincipal InvestigatorFunder's NameFunder RefLead Dept
462311Therapeutic potential of Sphingosine Kinase blockage in allergic anaphylaxis.Alirio Melendez RomeroMedical Research Council (MRC)G0700794Institute of Infection Immunity and Inflammation