Objective: To study the protective effects and mechanisms of erythromycin on human bronchial epithelial (HBE) cells damaged by interleukin-4.
Methods: The growth curve of HBE cells was recorded by MTT. The cells were divided into the following groups: control (incubation for 24, 48 h); IL-4 (0.01 mg/L, incubation for 24, 48 h); erythromycin intervention group 1 (4 mg/L erythromycin co-incubation for 24, 48 h after adding IL-4) and erythromycin intervention group 2 (40 mg/L erythromycin co-incubation for 24, 48 h after adding IL-4). The mitotic cycle of HBE cell was determined by flow cytometry and its apoptosis examined by Hoechst dyeing.
Results: The viability of HBE cells was significantly enhanced after a 24/48-hour treatment of erythromycin as compared with IL-4 group (P < 0.05, P < 0.01). In erythromycin intervention group 1, the cell ratios of G(0)/G(1) and S phases were (55.9 ± 2.5)% and (34.7 ± 3.4)% respectively while the rate of cell apoptosis was (9.5 ± 0.9)%. There were significant differences as compared with IL-4 group (P < 0.05). In erythromycin intervention group 2, the cell ratios of G(0)/G(1) and S phases were (55.1 ± 0.5)% and (36.2 ± 2.7)% respectively while the rate of cell apoptosis was (4.0 ± 0.6)%. There were significant differences as compared with IL-4 group (P < 0.05).
Conclusion: Erythromycin has protective effects on HBE cells damaged by IL-4. The mechanism is probably through influencing the mitotic cycle and inhibiting the apoptosis.