Effect Of 18β-glycyrrhetinic Acid On LPS-induced Nasal Epithelium Inflammation

Nasal polyps is defined as chronic inflammation of the severe edema of nose and paranasalsinuses,usually associated with chronic rhinosinusitis.As most scholars believed that the reason of the chronic mucous inflammation is due to various factors such as bacteria, fungi and the dysgenesis of anomaly which could induce the inflammation of the lateral wall of the nasal cavity. Although inflammation is the physiological protective responce to trauma and infection,but while the long-term infiltration of inflammatory cells could promote the interaction of cytokines(HMGB1、 TNF-α、IL-5、IL-8, et al.),the nasal mucosa inflammation continues to expand. But there has not been definitely concluded the pathogenesis.Silent information regulator 2,or classIII histone deacetylases,are related to the nicotinamide adenie dinucletide.Sirtuins involved in the upstream signaling pathway of the inflammation mechanism,which play an important role in the mechanism of aging and infection respiratory tract cells.This paper did researches in the following two aspects:Observed the expression of Sirt 6 (silent information regulator 2 related enzyme 6) and effect of 18 β-glycyrrhetinic acid to HMGB1 on LPS-induced human nasal epithelium inflammation Part one: The expression and significance of Sirt 6 in nasal mucosa. Objective:Preliminary discussion about the expression and significance of Sirt6 in the chronic sinusitis accompanied by nasal polyp。 Method:Using immunohistochemistry and Western blot method to observe Sirt6 protein distribution and expression level, in 23 nasal polyps cases and 8 normal nasal mucosa tissue cases。 Result:1. Immunohistochemical showed that Sirt6 protein mainly expressed in normal epithelial cells, but not or less in nasal polyps cases. In the normal epithelial cells,Sirt6 can be found in the nucleus of epithelial cells, the positive expression rate is significantly higher than the nasal polyps group; 2. Western blot showed Sirt6 protein levels in nasal polyps significantly lower than the normal group。Conclusion:Sirt6 protein expression is mainly in the normal nasal mucosa epithelial cells, the reduction may caused by participating in nasal polyps inflammatory reaction, it can be used as the treatment target of chronic sinusitis accompanied by nasal polyp.Part two:Effect of 18β-glycyrrhetinic acid on LPS-Induced nasal epithelium inflammationObjectives:To investigate the effect of 18β-glycyrrhetinic acid on LPS-Induced Human Nasal epithelium Inflammation.Methods:The expression of HMGB1 in the cytoplasm, nuclei of the exposed epithelial cells were determined by using immunofluorescence and Western blot.Results:Compared with the LPS group, the cells exposed to GA for 48 h showed significantly increased levels of Sirt6 and HMGB1 in the epithelial cells Immunofluorescence showed that expression of HMGB1 is confined to the nucleus, with the reducing the number of ciliated epithelial cells.Conclusion:GA can inhibit the translocation and release of HMGB 1 in human nasal epithelial cells in vitro, and promoted the expression of Sirt6,suggesting the value of GA in chronic rhinosinusitis with nasal polyps.