Faculty Collaboration Database

Inhibition of CDKS by roscovitine suppressed LPS-induced *NO production through inhibiting NFkappaB activation and BH4 biosynthesis in macrophages. Am J Physiol Cell Physiol 2009 Sep;297(3):C742-9

Date

06/26/2009

Pubmed ID

19553566

Pubmed Central ID

PMC2740392

DOI

10.1152/ajpcell.00138.2009

Scopus ID

2-s2.0-70349235380   29 Citations

Abstract

In inflammatory diseases, tissue damage is critically associated with nitric oxide ((*)NO) and cytokines, which are overproduced in response to cellular release of endotoxins. Here we investigated the inhibitory effect of roscovitine, a selective inhibitor of cyclin-dependent kinases (CDKs) on (*)NO production in mouse macrophages. In RAW264.7 cells, we found that roscovitine abolished the production of (*)NO induced by lipopolysaccharide (LPS). Moreover, roscovitine significantly inhibited LPS-induced inducible nitric oxide synthase (iNOS) mRNA and protein expression. Our data also showed that roscovitine attenuated LPS-induced phosphorylation of IkappaB kinase beta (IKKbeta), IkappaB, and p65 but enhanced the phosphorylation of ERK, p38, and c-Jun NH(2)-terminal kinase (JNK). In addition, roscovitine dose dependently inhibited LPS-induced expression of cyclooxygenase-2 (COX)-2, IL-1beta, and IL-6 but not tumor necrosis factor (TNF)-alpha. Tetrahydrobiopterin (BH(4)), an essential cofactor for iNOS, is easily oxidized to 7,8-dihydrobiopterin (BH(2)). Roscovitine significantly inhibited LPS-induced BH(4) biosynthesis and decreased BH(4)-to-BH(2) ratio. Furthermore, roscovitine greatly reduced the upregulation of GTP cyclohydrolase-1 (GCH-1), the rate-limiting enzyme for BH(4) biosynthesis. Using other CDK inhibitors, we found that CDK1, CDK5, and CDK7, but not CDK2, significantly inhibited LPS-induced (*)NO production in macrophages. Similarly, in isolated peritoneal macrophages, roscovitine strongly inhibited (*)NO production, iNOS, and COX-2 upregulation, activation of NFkappaB, and induction of GCH-1 by LPS. Together, our data indicate that roscovitine abolishes LPS-induced (*)NO production in macrophages by suppressing nuclear factor-kappaB activation and BH(4) biosynthesis, which might be mediated by CDK1, CDK5, and CDK7. Our results also suggest that roscovitine may inhibit inflammation and that CDKs may play important roles in the mechanisms by which roscovitine attenuates inflammation.

Author List

Du J, Wei N, Guan T, Xu H, An J, Pritchard KA Jr, Shi Y

Author

Kirkwood A. Pritchard PhD Professor in the Surgery department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Animals
Biopterin
Cell Line
Cyclin-Dependent Kinases
Dose-Response Relationship, Drug
GTP Cyclohydrolase
Gene Expression Regulation
Lipopolysaccharides
Macrophages
Mice
NF-kappa B
Nitric Oxide
Nitric Oxide Synthase Type II
Purines