Regulatory peptides
-
Regulatory peptides · Feb 2010
Meprin-alpha metalloproteases enhance lipopolysaccharide-stimulated production of tumour necrosis factor-alpha and interleukin-1beta in peripheral blood mononuclear cells via activation of NF-kappaB.
Lipopolysaccharide (LPS) induces the expression of a wide range of pro-inflammatory mediators via NF-kappaB activation. These pro-inflammatory cytokines, such as tumor necrosis factor-alpha (TNF-alpha) and interleukin-1beta (IL-1beta), may be important in triggering atherogenesis. We have previously observed that actinonin, a meprin inhibitor, suppressed the formation of atherosclerotic plaques and, in in vitro experiments, actinonin also had an effect on the way LPS altered THP-1 cell function. ⋯ Our results show that LPS-induced IL-1beta and TNF-alpha production by PBMCs was significantly reversed by meprin-alpha specific siRNA. In addition, the augmentation of meprin-alpha of the LPS-induced expression of TNF-alpha and IL-1beta was significantly decreased by Bay-117082, an inhibitor of NF-kappaB. In conclusion, our data indicate that meprin-alpha is capable of increasing LPS-induced production of cytokines in peripheral blood mononuclear cells, which might be associated with the activation of NF-kappaB.