PTGS2 and Sepsis: Yet, in contrast to the presumed protective effects of eNOS and SOD, inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2) and NF-κB (nuclear factor kappa-light-chain-enhancer of activated B cells) were also elevated in their expression in heart and lung of sepsis EV-treated mice, while in the liver eNOS and SOD2 were decreased, but so were COX-2 levels and IκBα (nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor, alpha) phosphorylation [66].