Clusterin (CLU) is a multifunctional protein whose expression has been related to many physiological and pathological processes. The most abundant gene product is the secreted form of CLU (sCLU) described as a prosurvival and cytoprotective protein. A nuclear CLU (nCLU) isoform involved in death and inhibition of cell growth has also been reported. The aims of the present work were to verify the differential presence of sCLU and nCLU in a primary culture of porcine aortic endothelial cells (pAEC) and to evaluate whether lipopolysaccharide (LPS) can influence their expression. LPS-treated pAEC expressed both mRNA isoforms but only sCLU protein was detected. LPS exposure induced transient mRNA and protein increases of sCLU at 1 h of treatment. In conclusion our data showed that in LPS-treated pAEC sCLU is the most abundant form of clusterin and nCLU can be considered irrelevant and is rarely translated.

Key words: Clusterin, LPS, pAEC, Small heat shock proteins