고장식염수의 면역조절작용 - 다핵성 호중구에서 NF-κB의 핵 내 이동과 TNF-α의 합성에 미치는 영향

Abstract

Purpose: According to current research, hypertonic saline has immunomodulatory effects. NF-κB is known as an important transcription factor involved in the production of inflammatory mediators during an inflammatory response. The purpose of this study was to determine the effect of hypertonic saline on both the NF-κB signaling pathway and on TNF-αsynthesis in stimulated PMNs. Methods: Isolated PMNs from healthy volunteers were subdivided into 3 groups by the incubation conditions: control (not stilmulated, isotonic condition), isotonic (stimulated, isotonic condition), hypertonic (stimulated, hypertonic condition). After nuclear proteins were isolated from the incubated PMNs, NF-κB was measured by Western blot. TNF-α was measured by ELISA from the culture media. Results: The relative densities of nuclear NF-κB after 45 minute incubation were 0.28±0.14 (control group), 0.97± 0.16 (isotonic group), and 0.58±0.07(hypertonic group). Isotonic and hypertonic groups (fMLP stimulated groups) showed a significantly higher relative density than control groups. Among the study groups, the hypertonic groups had a smaller increased level compared to isotonic groups and were found to be statistically significant. The results from the 90 minute incubated groups were similar to that of the 45 minute incubated groups. The concentration of TNF- αmeasured from stimulated groups (isotonic group, hypertonic group) were significantly higher than control groups. Similar to the NF-κB result, the concentrations of TNF-αin the hypertonic groups were significantly lower than isotonic groups. Longer incubation times were noted to display higher concentration in the stimulated groups. Conclusion: Stimulated PMNs incubated under hypertonic conditions showed a smaller increase in level of nuclear NF-κB and TNF-αsynthesis compared to isotonic conditions. As a result, suppression of the NF-κB signaling pathway in stimulated PMNs is considered one of the mechanisms of hypertonic saline’s immunomodulatory effect.