Inflammatory response modulation by epinephrine and norepinephrine

Relevance. Inflammation is a defense response of an organism to a pathogen. It appears in order to maintain homeostasis and is regulated by the immune, nervous, and endocrine systems. The hormones epinephrine and norepinephrine are produced in the adrenal medulla and in the brain, and are universal messengers that trigger the transmission of nerve impulses at synapses, and also have a receptor-mediated effect on immunocompetent cells. The aim of this study was to investigate adrenergic pathway regulation of inflammation on the neutrophil granulocytes in the presence of activators of innate immunity receptors. Materials and Methods. Neutrophil granulocytes were obtained from peripheral blood of healthy volunteers in a density gradient of Histopaque 1077 and Histopaque 1119 (Sigma Aldrich, Steinheim, Germany), and cultured in the presence of LPS, GMDP, epinephrine and norepinephrine. The amount of human neutrophil peptides 1-3 (HNP1-3) was examined using an enzyme-linked immunosorbent assay; the gene expression of TLR4, NOD2, ATF3 and A20 was determined using RT-PCR. Results and Discussion. Norepinephrine (noradrenaline) was found to decrease the synthesis of human neutrophils peptides 1-3 (HNP 1-3 defensins, alone and in the combination with agonists of TLR4 and NOD2 receptors - LPS and GMDP respectively. It was found out that there was no a statistically significant effect of epinephrine (adrenaline) on the production of HNP 1-3, including when combined with LPS and GMDP. As a result of the study, an increase in the levels of expression of the genes TLR4, NOD2 and regulator of inflammatory reactions A20 both in LPS- and GMDP- induced neutrophil culture were uncovered, while ATF3 was increased only in LPS-induced neutrophil culture. Epinephrine demonstrated the absence of a statistically significant effect on the expression of the studied genes. While norepinephrine significantly increased the expression of A20 genes. Conclusion. The data obtained shows that norepinephrine can reduce the synthesis of HNP 1-3, including the one induced by LPS and GMDP. Moreover, the ability of norepinephrine to induce the expression of A20 may play a significant role in modulation of inflammation.