Pseudomonas signal molecule 3-oxo-C12-homoserine lactone interferes with binding of rosiglitazone to human PPARgamma
Peroxisome proliferator activated receptor (PPARgamma) has been suggested as a target for anti-inflammatory therapy in chronic lung disease, including infection with Pseudomonas aeruginosa. However, the P. aeruginosa signal molecule N-(3-oxo-dodecanoyl)-l-homoserine lactone (3-oxo-C12-HSL) has been reported to inhibit function of PPARs in mammalian cells. This suggests that binding of 3-oxo-C12-HSL to PPARs could increase inflammation during P. aeruginosa infection, particularly if it could compete for binding with other PPAR ligands. We investigated the ability of 3-oxo-C12-HSL to bind to a PPARgamma ligand binding domain (LBD) construct, and to compete for binding with the highly active synthetic PPARgamma agonist rosiglitazone. We demonstrate that 3-oxo-C12-HSL binds effectively to the PPARgamma ligand binding domain, and that concentrations of 3-oxo-C12-HSL as low as 1 nM can effectively interfere with the binding of rosiglitazone to the PPARgamma ligand binding domain. Because 3-oxo-C12 HSL has been demonstrated in lungs during P. aeruginosa infection, blockade of PPARgamma-dependent signaling by 3-oxo-C12-HSL produced by the infecting P. aeruginosa could exacerbate infection-associated inflammation, and potentially impair the action of PPAR-activating therapy. Thus the proposed use of PPARgamma agonists as anti-inflammatory therapy in lung P. aeruginosa infection may depend on their ability to counteract the effects of 3-oxo-C12-HSL.
|ISBN||1769-714X (Electronic) 1286-4579 (Linking)|
|Authors||Cooley, M. A.; Whittall, C.; Rolph, M. S.;|
|Publisher Name||MICROBES AND INFECTION|
|URL link to publisher's version||http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=20074659|
|OpenAccess link to author's accepted manuscript version||https://publications.gimr.garvan.org.au/open-access/10811|