[Expression of peroxiredoxin I in the rats exposed to silica].
OBJECTIVE
To evaluate the change in protein expression of peroxiredoxin I (Prx I) during pulmonary fibrosis among rats exposed to silica dust and to investigate the role of Prx I in pulmonary fibrosis.


METHODS
Ninety male Wistar rats were randomly divided into control group (n = 60) and experimental group (n = 30). The control group received intratracheal perfusion of saline (1 ml), while the experimental group received intratracheal perfusion of suspension of silica dust (50 mg/ml) to establish a rat model of silicosis. At 1, 2, 3, 4, 6, or 8 weeks after treatment, 10 rats in control group and 5 rats in experimental group were sacrificed. The lung tissues were collected for conventional pathological observation. The protein expression of Prx I at each time point was measured by immunohistochemistry and Western blot.


RESULTS
Among the rats exposed to silica dust, Prx I was seen in the form of brown particles that were mainly distributed in the alveolar septa and the cytoplasm of alveolar epithelial cells, macrophages, vascular endothelial cells, and smooth muscle cells around the blood vessels and tracheae. The control group showed weak protein expression of Prx I, and the experimental group had significantly higher protein expression of Prx I than the control group at all time points (P < 0.05). In the experimental group, the protein expression of Prx I was upregulated significantly at 1 and 2 weeks and decreased at 3∼8 weeks.


CONCLUSIONS
The change in protein expression of Prx I may be one of the important causes of the onset and development of pulmonary fibrosis in rats exposed to free silica.
Department of Pathology, Hebei United University, Tangshan,Hebei province 063000, China.
Jia-qi
JQ
Liu
Su-qin
SQ
Zheng
Yin-zhou
YZ
Sang
Ying
Y
Sun
Hong-wei
HW
Zhang
Yan-jie
YJ
Xiong
Yue
Y
Yi
Jun-ran
JR
Wang
D000818:Animals; D004195:Disease Models, Animal; D008168:Lung / Q000201:enzymology / Q000473:pathology; D008297:Male; D054464:Peroxiredoxins / Q000378:metabolism*; D011658:Pulmonary Fibrosis / Q000201:enzymology / Q000473:pathology; D051381:Rats; D017208:Rats, Wistar; D012822:Silicon Dioxide / Q000633:toxicity; D012829:Silicosis / Q000201:enzymology* / Q000473:pathology
D012822:Silicon Dioxide; D054464:Peroxiredoxins