Dysregulation of the ubiquitin-proteasome system by curcumin suppresses coxsackievirus B3 replication.
نویسندگان
چکیده
Curcumin (diferuloylmethane), a natural polyphenolic compound extracted from the spice turmeric, has been reported to have anti-inflammatory, antioxidant, and antiproliferative properties by modulating multiple cellular machineries. It inhibits several intracellular signaling pathways, including the mitogen-activated protein kinases (MAPKs), casein kinase II (CKII), and the COP9 signalosome (CSN), in various cell types. It has also been recently demonstrated that exposure to curcumin leads to the dysregulation of the ubiquitin-proteasome system (UPS). Coxsackievirus infection is associated with various diseases, including myocarditis and dilated cardiomyopathy. In searching for new antiviral agents against coxsackievirus, we found that treatment with curcumin significantly reduced viral RNA expression, protein synthesis, and virus titer and protected cells from virus-induced cytopathic effect and apoptosis. We further demonstrated that reduction of viral infection by curcumin was unlikely due to inhibition of CVB3 binding to its receptors or CVB3-induced activation of MAPKs. Moreover, gene silencing of CKII and Jab1, a component of CSN, by small interfering RNAs did not inhibit the replication of coxsackievirus, suggesting that the antiviral action of curcumin is independent of these pathways. Finally, we showed that curcumin treatment reduced both the 20S proteasome proteolytic activities and the cellular deubiquitinating activities, leading to increased accumulation of ubiquitinated proteins and decreased protein levels of free ubiquitin. We have recently demonstrated that the UPS-mediated protein degradation and/or modification plays a critical role in the regulation of coxsackievirus replication. Thus, our results suggest an important antiviral effect of curcumin wherein it potently inhibits coxsackievirus replication through dysregulation of the UPS.
منابع مشابه
Ubiquitination Is Required for Effective Replication of Coxsackievirus B3
BACKGROUND Protein ubiquitination and/or degradation by the ubiquitin/proteasome system (UPS) have been recognized as critical mechanisms in the regulation of numerous essential cellular functions. The importance of the UPS in viral pathogenesis has become increasingly apparent. Using murine cardiomyocytes, we have previously demonstrated that the UPS plays a key role in the replication of coxs...
متن کاملProteasome inhibition attenuates coxsackievirus-induced myocardial damage in mice.
Coxsackievirus B3 (CVB3) is one of the most prevalent pathogens of viral myocarditis, which may persist chronically and progress to dilated cardiomyopathy. We previously demonstrated a critical role of the ubiquitin-proteasome system (UPS) in the regulation of coxsackievirus replication in mouse cardiomyocytes. In the present study, we extend our interest to an in vivo animal model to examine t...
متن کاملEffect of Activation and Inhibition of Cellular PKR on Coxsackievirus B3 Replication
The ds-RNA activated protein kinase (PKR) is a serine-threonine kinase with MW of 68 KDa. It belongs to a family of kinases that control one of the translational initiation factors, eIF2. PKR is produced at high level in response to viral infection. This protein by phosphorylating eIF2 inhibits cellular protein synthesis. In this study, the effect of gamma interferon (IFN-γ), an activator, and ...
متن کاملPA28 modulates antigen processing and viral replication during coxsackievirus B3 infection
The function of the proteasome is modulated at the level of subunit expression and by association with its regulatory complexes. During coxsackievirus B3 (CVB3) myocarditis, IFN-induced formation of immunoproteasomes (ip) is known to be critical for regulating immune modulating molecules. The function of the IFN-γ-inducible proteasome regulator subunits PA28 α and β, however, in this context wa...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
- Journal of virology
دوره 81 7 شماره
صفحات -
تاریخ انتشار 2007