Objectives ; In this study, effects of haepyoijintang(HIJ) on the increase in airway epithelial mucosubstances of rats and ATP-, PMA-, EGF- or TNF-α-induced MUC5AC mucin production and gene expression from human airway epithelial cells were investigated.
Materials and Methods ; Hypersecretion of airway mucus was induced by exposure of rats to SO2 during 3 weeks. Effect of orally-administered HIJ during 2 weeks on increase in airway epithelial mucosubstances from tracheal goblet cells of rats was evaluated using histopathological analysis after staining the epithelial tissue with PAS-alcian blue. Possible cytotoxicity of HIJ was evaluated by examining the potential damage of kidney and liver functions by measuring serum GOT/GPT activities and serum BUN and creatinine concentrations of rats and the body weight gain during experiment, after administering HIJ orally. At the same time, the effect of HIJ on ATP-, PMA-, EGF- or TNF-α-induced MUC5AC mucin production and gene expression from human airway epithelial cells(NCI-H292) were investigated. Confluent NCI-H292 cells were pretreated for 30min in the presence of HIJ and treated with ATP(200μM), PMA(10ng/ml), EGF(25ng/ml) or TNF-α(0.2nM) for 24 hrs, to evaluate the effect of HIJ both on ATP-, PMA-, EGF- or TNF-α-induced MUC5AC mucin production using enzyme-linked immunosorbent assay(ELISA) and on gene expression by the same inducers using reverse transcription-polymerase chain reaction(RT-PCR).
Results ; (1) HIJ decreased the amount of intraepithelial mucosubstances of trachea of rats. (2) HIJ did not show renal and hepatic toxicities and did not affect body weight gain of rats during experiment. (3) HIJ significantly inhibited ATP-, PMA-, EGF-, and TNF-α-induced MUC5AC mucin productions from NCI-H292 cells. (4) HIJ significantly inhibited ATP-, PMA-, EGF-, and TNF-α-induced MUC5AC mucin gene expression from NCI-H292 cells.
Conclusion ; The result from the present study suggests that HIJ might control the production and gene expression of airway mucin observed in various respiratory diseases accompanied by mucus hypersecretion and do not show in vivo toxicity to liver and kidney functions after oral administration. Effect of HIJ with their diverse components should be further investigated using animal experimental models that can reflect the pathophysiology of airway diseases through future studies.
Key words : Haepyoijin-tang(HIJ), Airway, Mucin, Gene