[Effect of PM2.5 collected during the dust and non-dust periods on the viability and gap junctional intercellular communication in human lung fibroblasts].
ABSTRACT To investigate the effects of PM2.5 collected during the dust and non-dust periods on the viability and gap junctional intercellular communication (GJIC) in human lung fibroblasts.
Human lung fibroblasts were treated with PM2.5 suspension and its organic and inorganic extracts at various concentrations for 24 h. The cellular viability was measured with MTT methods, and the GJIC between human lung fibroblasts was detected by the scrape loading dye transfer assay.
PM2.5 suspension from both sources and the inorganic extracts of dust PM2.5 significantly decreased the viability of human lung fibroblast in a dose-dependent manner. Compared with other preparations, the dust PM2.5 suspension had the highest effect. Gap junctional intercellular communication between human lung fibroblasts was significantly inhibited by the different composition of PM2.5 from both sources in a dose-dependent manner. The inhibitory effects on GJIC were in the order of organic extract of PM2.5 > suspension > inorganic extract.
Composition and source of PM2.5 are important factors which influnce the toxic effects on cells. The composition of PM2.5 from both sources can inhibit GJIC, suggesting decreasing GJIC may be related to the biological mechanisms of toxicity caused by PM2.5.
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ABSTRACT: 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.Toxicology in Vitro 07/2007; 21(4):632-8. · 3.21 Impact Factor