Estriol Inhibits Dermcidin Isoform-2 Induced Inflammatory Cytokine Expression Via Nitric Oxide Synthesis in Human Neutrophil.

Abstract

An increase in the level of cytokines like TNF-α and IL-6 causes the inflammatory surge in acute ischemic heart disease (AIHD). A high-level dermcidin isoform-2 (DCN-2) occurrence in AIHD was subjected to determine a possible regulation of cytokines expression. The effect of estrogen to counteract the inflammatory response was determined. Blood was collected from AIHD patients and normal volunteers with consent. Nitric oxide (NO) synthesis was done with methemoglobin method.TNF-α and IL-6 expression were determined by ELISA and Western blot. (DCN-2) incubation with 120nM to the normal neutrophil solution for 2h resulted in the increase of TNF-α from 3.82±1.53pg/ml to 20.7±6.9pg/ml and IL-6 from 3.27±1.52pg/ml to 47.07±3.4pg/ml. In AIHD patients, the cytokine level was18.3- 27.3pg/ml, with a median value 21.86pg/ml (TNF-α) and IL-6 level was 23.54- 52.73pg/ml, with a median value 42.16pg/ml. Treatment with 0.6nM estriol, a kind of female steroid hormone estrogen for 45min decreased the elevated cytokine level in 120nM DCN-2 treated normal neutrophils. DCN-2 induced TNF-α synthesis in neutrophils was further determined by Western blot technique with a thickened band intensity of TNF-α. Estriol (0.6nM) treatment also influenced the DCN-2 induced inhibition of nitric oxide (NO) synthesis from 0nmol NO/ml to 0.56nmol/ml. The subsequent reduction of TNF-α level correlates the increase of NO level. In conclusion, the stress-induced DCN-2 production in AIHD propagates the inflammatory response. Steroid molecule like estriol plays a protective role by reducing DCN-2 responses in the NO synthesis.