Müller-Pillasch F, Gress T M, Yamaguchi H, Geng M, Adler G, Menke A
Department of Internal Medicine I, University of Ulm, Germany.
Pancreas. 1997 Aug;15(2):168-75. doi: 10.1097/00006676-199708000-00009.
Enhanced synthesis and deposition of extracellular matrix (ECM) components is a characteristic feature during regeneration from acute cerulein-induced pancreatitis in rats. Transforming growth factor beta 1 (TGF beta 1) has been suggested to be an important modulator of the ECM by interfering with a number of essential processes such as the synthesis of ECM components. To study the involvement of the ECM degrading proteases (matrix metalloproteinases; MMPs) and their specific inhibitors in the process of pancreatic regeneration, we examined the expression of these genes on the transcript level and the activation of the corresponding enzymes by use of zymographies. Pancreatic RNA and protein were extracted from rats sacrificed 1, 2, 3, 5, and 7 days after induction of cerulein pancreatitis. To investigate the influence of TGF beta on gene expression of ECM proteases and their specific inhibitors, we blocked the activity of TGF beta 1 during regeneration from acute pancreatitis by use of neutralizing antibodies against TGF beta 1. Steady levels of 72-kD type IV collagenase (MMP-2), stromelysin (MMP-3), and tissue inhibitor of metalloproteinase 2 (TIMP-2) mRNA were significantly increased 2 days after induction of pancreatitis. MMP-9 and MMP-3 enzyme activity was elevated 12 h after induction of pancreatitis, whereas MMP-2 activity increased 12 h later. Inhibition of TGF beta 1 by neutralizing antibodies only reduced the amount of stromelysin transcripts throughout pancreatic regeneration. In summary, ECM degrading proteases, in particular stromelysin, appear to be involved in ECM remodeling during pancreatic regeneration. TGF beta 1 may be responsible for regulation of stromelysin transcription.
细胞外基质（ECM）成分的合成和沉积增强是大鼠急性雨蛙肽诱导的胰腺炎再生过程中的一个特征。转化生长因子β1（TGFβ1）被认为是ECM的重要调节因子，它通过干扰许多重要过程，如ECM成分的合成。为了研究ECM降解蛋白酶（基质金属蛋白酶；MMPs）及其特异性抑制剂在胰腺再生过程中的作用，我们通过酶谱法检测了这些基因在转录水平的表达以及相应酶的激活情况。从雨蛙肽胰腺炎诱导后1、2、3、5和7天处死的大鼠中提取胰腺RNA和蛋白质。为了研究TGFβ对ECM蛋白酶及其特异性抑制剂基因表达的影响，我们在急性胰腺炎再生过程中使用抗TGFβ1的中和抗体阻断TGFβ1的活性。胰腺炎诱导后2天，72-kD IV型胶原酶（MMP-2）、基质溶解素（MMP-3）和金属蛋白酶组织抑制剂2（TIMP-2）mRNA的稳定水平显著升高。胰腺炎诱导后12小时，MMP-9和MMP-3酶活性升高，而MMP-2活性在12小时后增加。用中和抗体抑制TGFβ1仅在整个胰腺再生过程中减少了基质溶解素转录本的数量。总之，ECM降解蛋白酶，特别是基质溶解素，似乎参与了胰腺再生过程中的ECM重塑。TGFβ1可能负责调节基质溶解素的转录。
