高氧诱导慢性肺疾病早产鼠肝肠组织的自由基变化

Effect of hyperoxia on the expression of secretory component in human intestinal epithelial Caco-2 cells

AIM: To explore the effect of hyperoxia on the expression of secretory component (SC) in human intestinal epithelial Caco-2 cells.

METHODS: The number of Caco-2 cells was counted with a hemacytometer, and cell division was determined by Giemsa staining. The changes in the expression levels of SC in Caco-2 cells were detected by immunocytochemistry.

RESULTS: Caco-2 cells exhibited exponential growth in air containing 400 mL/L O₂. Cell growth was partially inhibited when the proportion of oxygen in air was elevated to 600 mL/L, and completely inhibited when elevated to 900 mL/L. The division index of treated cells was 2.5% in air, 3.3% in 400 mL/L O₂, and 1.3% in 600 mL/L O₂. Many cells died in 900 mL/L O₂. Compared with cells incubated in air, the expression of SC was up-regulated in 400 mL/L and 600 mL/L O₂. The ability of intestinal epithelial cells to express SC was limited in 900 mL/L O₂. Compared with cells incubated in 400 mL/L O₂, the expression of SC was down-regulated in 600 mL/L O₂.

CONCLUSION: Moderately high concentrations of oxygen promote cell growth and SC expression in Caco-2 cells, whereas extremely high concentrations of oxygen inhibit cell growth and SC expression. High levels of SC are beneficial to maintaining and balancing the intestinal mucosa and inhibiting bacterial invasion.