Differential expression of nitric oxide synthases in porcine aortic endothelial cells during LPS-induced apoptosis

• Main Authors: Bernardini Chiara (Author), Greco Francesca (Author), Zannoni Augusta (Author), Bacci Maria Laura (Author), Seren Eraldo (Author), Forni Monica (Author)
• Format: Book
• Published: BMC, 2012-11-01T00:00:00Z.
• Subjects: article
• Online Access: Connect to this object online.
• Notes: 10.1186/1476-9255-9-47; 1476-9255
• Keywords: Endothelial cells; Endotoxin; Apoptosis; NO; Therapeutics. Pharmacology; RM1-950
• Source: Journal of Inflammation, Vol 9, Iss 1, p 47 (2012)

<p>Abstract</p> <p>Background</p> <p>It is well known that nitric oxide (NO) is generated by a family of constitutively (nNOS and eNOS) or inducibly (iNOS) expressed enzymes and takes part in different aspects of the inflammatory response; nevertheless, its effective role in the pathogenesis of multiple organ dysfunction and septic shock is not fully understood.</p> <p>Methods</p> <p>To investigate the Nitric Oxide Synthases (NOSs) expression in endothelial cells during endotoxin exposure and the involvement of NO in lipopolysaccharide (LPS)-induced apoptosis, primary cultures of porcine Aortic Endothelial Cells (pAECs) were exposed to LPS for different time periods (1-24 h) and to LPS + L-NAME (15 h).</p> <p>Results</p> <p>Lipopolysaccharide induced an increase in mRNA and protein iNOS expression; on the contrary, the expression of eNOS was decreased. Furthermore, NOSs localisation was in part modified by LPS treatment. No alteration in the total level of Nitric Oxide was observed. L-NAME (5 mM) addition determined a slight decrease of LPS-induced apoptosis.</p> <p>Conclusions</p> <p>Endotoxin treatment strongly influenced NOS expression with an upregulation of iNOS and a simultaneous down regulation of eNOS. Moreover, in our model, the involvement of NO on LPS-induced apoptosis is very modest, suggesting that different pathways are involved in the regulation of this process.</p>