Effects of dust storm PM 2.5 on cell proliferation and cell cycle in human lung fibroblasts

Abstract

Reports on the effects of PM 2.5 from dust storm on lung cells are limited. We compared the effects of PM 2.5 collected in dust storm days (dust storm PM 2.5) with that in sunshiny and non-dust storm days (normal PM 2.5) on cell proliferation and cell cycle in human lung fibroblasts. Our results showed that both dust storm and normal PM 2.5 had biphasic effects on cell proliferation, namely, stimulated cell proliferation at lower concentrations while inhibited it at higher concentrations. On the contrary, the organic and inorganic extracts from dust storm and normal PM 2.5 significantly inhibited the proliferation in human lung fibroblasts at the concentrations corresponding to their mass contents in PM 2.5 samples. The flow cytometry showed that the number of cells in G2/M phase increased significantly after treatment with the dust storm and normal PM 2.5. The inorganic and organic extracts from PM 2.5, however, induced cell arrest in S phase and G0/G1 phase, respectively. It seems that the biphasic effects of both dust storm and normal PM 2.5 on cell proliferation may not be related to their inorganic or organic extractable components.