Effects of dust storm PM2.5 on cell proliferation and cell cycle in human lung fibroblasts

Department of Occupational and Environmental Health Sciences, Peking University, Peping, Beijing, China
Toxicology in Vitro (Impact Factor: 2.9). 07/2007; 21(4):632-8. DOI: 10.1016/j.tiv.2006.12.013
Source: PubMed


Reports on the effects of PM2.5 from dust storm on lung cells are limited. We compared the effects of PM2.5 collected in dust storm days (dust storm PM2.5) with that in sunshiny and non-dust storm days (normal PM2.5) on cell proliferation and cell cycle in human lung fibroblasts. Our results showed that both dust storm and normal PM2.5 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 PM2.5 significantly inhibited the proliferation in human lung fibroblasts at the concentrations corresponding to their mass contents in PM2.5 samples. The flow cytometry showed that the number of cells in G2/M phase increased significantly after treatment with the dust storm and normal PM2.5. The inorganic and organic extracts from PM2.5, however, induced cell arrest in S phase and G0/G1 phase, respectively. It seems that the biphasic effects of both dust storm and normal PM2.5 on cell proliferation may not be related to their inorganic or organic extractable components.

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    • "Möller and colleagues [50] reported effects on phagocytosis, phagosome transport mechanisms and cytoskeletal integrity. PAHs-rich PM0.2, produced by combustion of solid fuels, induced G2/M arrest in macrophages [23], while organic extracts from PM2.5 and PM10 arrested the cell cycle of different human cell lines in G0/G1 [22,51]. Several PAHs are able to alter the cell cycle in various ways; dibenzo[a,l]pyrene induces G2/M arrest in human mammary carcinoma MCF-7 cells [52], while it delays HEL fibroblasts in the S phase [53]. "
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