[DNA methylation levels of genome in cFb transdifferentiation induced by SiO2 in rats].
OBJECTIVE
To explore the DNA methylation levels of genome in cFb transdifferentiation induced by SiO2 in rats.


METHODS
The primary macrophages and fibrocytes of SD rats were co-cultured directly and indirectly, which were exposed to SiO2 at the doses of 25, 50 and 100 g/ml. The transdifferentiation of cFb was identified with immunohistochemical assay. The genomic DNA methylation levels of cFb were detected with HPLC.


RESULTS
Under the condition of indirect co-culture, as compared with control group, the genomic DNA methylation levels of cFb exposed to SiO2 at the doses of 25, 50 and 100 g/ml reduced by 19.9%, 26.9% and 30.3%, respectively (P < 0.05); as compared with cFb exposed to 100 g/ml SiO2, the genomic DNA methylation levels of cFb exposed to 5-aza-dC decreased by 22.0% (P < 0.05). Under the condition of ThinCert(TM) direct co-culture, as compared with control group, the genomic DNA methylation levels of cFb exposed to SiO2 at the doses of 25, 50 and 100 g/ml reduced by 22.2%, 30.2% and 36.7%, respectively (P < 0.05); as compared with cFb exposed to 100 g/ml SiO2, the genomic DNA methylation levels of cFb exposed to 5-aza-dC decreased by 20.6% (P < 0.05).


CONCLUSIONS
Under the co-culture condition in vitro, SiO2 could reduce the genomic DNA methylation levels of cFb. The ThinCert(TM) direct co-culture can be used to study the silicosis fibrosis.
Department of Occupational Health Collage of Public Health, Zhengzhou University, Zheng-zhou, China.
Yong-xing
YX
Wang
Wu
W
Yao
Bin
B
Gao
Yong-cheng
YC
Yao
Yi-ming
YM
Wu
Chang-fu
CF
Hao
D000818:Animals; D054338:Cell Transdifferentiation / Q000187:drug effects*; D002478:Cells, Cultured; D018920:Coculture Techniques; D019175:DNA Methylation; D005347:Fibroblasts / Q000166:cytology / Q000187:drug effects*; D016678:Genome / Q000187:drug effects; D008168:Lung / Q000166:cytology / Q000187:drug effects; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D012822:Silicon Dioxide / Q000009:adverse effects*
D012822:Silicon Dioxide