Effects of Bovine Lactoferrin on Rat Intestinal Epithelial Cells

Objective: To determine the effects of bovine lactoferrin (bLF) on cell viability, proliferation, and the protective roles in intestinal epithelial cells-6 (IEC-6) treated by lipopolysaccharide (LPS). Methods: Cell viability and proliferation of IEC-6 were detected by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and Brdu assay separately. Cell cycle distribution was analyzed by flow cytometry. Inflammatory cytokines were analysed by real-time PCR and ELISA. Western blot was utilized to measure the level of MAPK and NF-kappa beta nuclear translocation. Results: Dose-dependent effects of bLF on cell viability and proliferation were observed in IEC-6 cells (bothP < 0.05), especially at a dose of 100 mu g/ml. The percentage of cells in the G2 and S phase was significantly higher than those of the control group (8.17 +/- 0.49% vs 4.72 +/- 0.55%,P < 0.01 and 12.75 +/- 0.33% vs 9.48 +/- 0.33%,P < 0.01, respectively). The mRNA level of IL-1 beta, IL-6 and TNF-alpha was decreased by co-stimulation of bLF and LPS compared with the LPS treatments alone in IEC-6 cells (allP < 0.001). The secretion of IL-6 and TNF-alpha were also decreased by co-stimulation of bLF and LPS (bothP < 0.01). Bovine lactoferrin treatment at dose of 100 mu g/ml could inhibit the activation of MAPK/NF-kappa beta signal pathway induced by LPS (bothP < 0.001). Conclusions: Bovine lactoferrin could promote the cell viability and proliferation, and have anti-inflammatory effects via inhibition of the activation of MAPK and NF-kappa beta nuclear translocation. Supplementation of formula with bLF may be beneficial in preventing NEC in preterm infants.