Growth plate zonal microarray analysis shows upregulation of extracellular matrix genes and downregulation of metalloproteinases and cathepsins following irradiation.
Growth plate zonal microarray analysis shows upregulation of extracellular matrix genes and downregulation of metalloproteinases and cathepsins following irradiation.
复制标题
生长板区域微阵列分析显示，辐射后细胞外基质基因上调，金属蛋白酶和组织蛋白酶下调。
DOI：
10.1007/s00223-007-9025-1
复制
发表时间：
2007
影响因子：
4.2
通讯作者：
Damron,TimothyA
中科院分区：
文献类型：
--
作者：
Zhang,Mingliang;Wang,Yan;Middleton,FrankA;Horton,JasonA;Farnum,CorneliaE;Damron,TimothyA
虽然辐照后生长板基质面积分数增加，但细胞外基质（ECM）基因在这种情况下的表达尚未研究。假设正常表达的ECM基因在辐照后会上调。取6只5周龄Sprague-Dawley大鼠的右肢照射，以左肢为对照。一半的动物在1周后收获，一半在2周后收获。对激光显微解剖分离的正常和辐照后胫骨生长板增生区（PZ）和肥厚区（HZ）软骨细胞在每个时间点进行微阵列检测。采用原位杂交（ISH）和实时聚合酶链反应（PCR）对所选基因的表达进行检测。照射后1周和2周，正常生长板中正常表达的ECM基因和正常生长板中不高表达的ECM基因均出现上调。金属蛋白酶和组织蛋白酶下调。辐照后PZ基因表达表现出正常HZ的特征，提示终末分化过早。在正常生长板中不高表达的ECM基因包括几个富含亮氨酸的小蛋白和ezrin-radixin-moesin家族的成员。辐照对组织蛋白酶K （Ctsk）、整合素结合唾液蛋白（Ibsp）和前胶原II α 1 （Col2a1）的影响，通过ISH和实时PCR检测，与微阵列结果高度相关。生长板辐射损伤后基质的积累与基因表达的变化密切相关。非损伤生长板中通常不高表达的基因的上调表明它们在损伤和修复反应中的重要性。
Although the growth plate matrix area fraction increases after irradiation, extracellular matrix (ECM) gene expression in this context has not been studied. The hypothesis was that normally expressed ECM genes would be upregulated after irradiation. The right limbs of six Sprague-Dawley 5-week-old rats were irradiated with the left limbs as controls. Half of the animals were harvested after 1 week and half after 2. Microarray was conducted from normal and irradiated tibial growth plate proliferative zone (PZ) and hypertrophic zone (HZ) chondrocytes separated by laser microdissection at each time point.In situhybridization (ISH) and real-time polymerase chain reaction (PCR) were used to confirm expression of selected genes. At 1 and 2 weeks after irradiation, both normally expressed ECM genes and others not highly expressed in the normal growth plate showed upregulation. Metalloproteinases and cathepsins were downregulated. PZ gene expression after irradiation exhibited features of the normal HZ, suggesting premature terminal differentiation. ECM genes not highly expressed in the normal growth plate included several members of the small leucine-rich proteins and the ezrin–radixin–moesin family. The effects of irradiation on cathepsin K (Ctsk), integrin binding sialoprotein (Ibsp), and procollagen II alpha 1 (Col2a1), as determined by ISH and real-time PCR, were highly correlated with the microarray results. Accumulation of matrix following radiation injury to the growth plate correlated well with changes in gene expression. Upregulation of genes not normally highly expressed in the noninjured growth plate suggests their importance in the injury and repair response.