Li Wenbin, Chang Liwen, Rong Zhihui, Liu Wei
Department of Pediatrics, Tongji Hospital, Tongji Medical University, Huazhong University of Science and Technology, Wuhan, 430030, China.
J Huazhong Univ Sci Technolog Med Sci. 2011 Apr;31(2):251-257. doi: 10.1007/s11596-011-0262-1. Epub 2011 Apr 20.
This study examined the effects of retinoic acid (RA), PD98059, SP600125 and SB203580 on the hyperoxia-induced expression and regulation of matrix metalloproteinase-2 (MMP-2) and metalloproteinase-2 (TIMP-2) in premature rat lung fibroblasts (LFs). LFs were exposed to hyperoxia or room air for 12 h in the presence of RA and the kinase inhibitors PD98059 (ERK1/2), SP600125 (JNK1/2) and SB203580 (p38) respectively. The expression levels of MMP-2 and TIMP-2 mRNA were detected by semi-quantitative reverse transcription polymerase chain reaction (RT-PCR). MMP-2 activity was measured by zymography. The amount of p-ERK1/2, REK1/2, p-JNK1/2, JNK1/2, p-p38 and p38 was determined by Western blotting. The results showed that: (1) PD98059, SP600125 and SB203580 significantly inhibited p-ERK1/2, p-JNK1/2 and p-p38 respectively in LFs; (2) The expression of MMP-2 mRNA in LFs exposed to hyperoxia was decreased after treatment with RA, SP600125 and SB203580 respectively (P<0.01 or 0.05), but did not change after treatment with PD98059 (P>0.05). Meanwhile, RA, PD98059, SP600125 and SB203580 had no effect on the expression of TIMP-2 mRNA in LFs exposed to room air or hyperoxia (P>0.05); (3) The expression of pro- and active MMP-2 experienced no change after treatment with RA or SP600125 in LFs exposed to room air (P>0.05), but decreased remarkably after hyperoxia (P<0.01 or 0.05). SB203580 inhibited the expression of pro- and active MMP-2 either in room air or under hyperoxia (P<0.01). PD98059 exerted no effect on the expression of pro- and active MMP-2 (P<0.05). It was suggested that RA had a protective effect on hyperoxia-induced lung injury by down-regulating the expression of MMP-2 through decreasing the JNK and p38 activation in hyperoxia.
本研究检测了视黄酸（RA）、PD98059、SP600125和SB203580对高氧诱导的早产大鼠肺成纤维细胞（LFs）中基质金属蛋白酶-2（MMP-2）和金属蛋白酶组织抑制因子-2（TIMP-2）表达及调控的影响。分别在存在RA及激酶抑制剂PD98059（ERK1/2）、SP600125（JNK1/2）和SB203580（p38）的情况下，将LFs暴露于高氧或室内空气中12小时。通过半定量逆转录聚合酶链反应（RT-PCR）检测MMP-2和TIMP-2 mRNA的表达水平。用酶谱法测定MMP-2活性。通过蛋白质印迹法测定p-ERK1/2、REK1/2、p-JNK1/2、JNK1/2、p-p38和p38的含量。结果显示：（1）PD98059、SP600125和SB203580分别显著抑制LFs中的p-ERK1/2、p-JNK1/2和p-p38；（2）分别用RA、SP600125和SB203580处理后，暴露于高氧的LFs中MMP-2 mRNA的表达降低（P<0.01或0.05），但用PD98059处理后无变化（P>0.05）。同时，RA、PD98059、SP600125和SB203580对暴露于室内空气或高氧的LFs中TIMP-2 mRNA的表达无影响（P>0.05）；（3）在暴露于室内空气的LFs中，用RA或SP600125处理后前MMP-2和活性MMP-2的表达无变化（P>0.05），但在高氧后显著降低（P<0.01或0.05）。SB203580在室内空气或高氧条件下均抑制前MMP-2和活性MMP-2的表达（P<0.01）。PD98059对前MMP-2和活性MMP-2的表达无影响（P>0.05）。提示RA通过降低高氧时JNK和p38的激活，下调MMP-2的表达，对高氧诱导的肺损伤具有保护作用。
