title: Differential expression of matrix metalloproteinases and their inhibitors in human and mouse lung development.
abstract: Lung development is a highly orchestrated process characterized by timed expression and activation of growth factor and protease/antiprotease systems. This interplay is essential in regulating vasculogenesis, alveolarization, and epithelial to mesenchymal transition during lung development. Alterations in the proteolytic/antiproteolytic balance of the lung have been associated with several respiratory diseases characterized by changes in the lung extracellular matrix (ECM). Here, we characterized the expression pattern of matrix metalloproteases (MMP) and their inhibitors, the tissue inhibitors of metalloproteases (TIMP), in human and mouse lung development. Using MMP/TIMP expression arrays, RT-PCR, Western Blotting, and ELISA analyses, we demonstrate that fetal human lung is characterized by a dominant proteolytic profile with high MMP-2 and little TIMP-3 expression. Adult human lung, in contrast, exhibits a more anti-proteolytic profile with decreased MMP-2 and increased TIMP-3 expression. MMP-14, MMP-20, TIMP-1, and TIMP-2 were constitutively expressed, irrespective of the developmental stage. Similar results were obtained using mouse lungs of different developmental stages, with the addition that in mouse lung, TIMP-2 and TIMP-3 were upregulated as lung development progressed. Exposure of neonatal mice to chronic hypoxia (10% O2), a stimulus that leads to an arrest of lung development, resulted in upregulation of MMP-2 with a concomitant downregulation of TIMP-2. These results provide a comprehensive analysis of MMP and TIMP expression during human and mouse lung development. MMP-2, TIMP-2, and TIMP-3 may be key regulatory enzymes during lung development, possibly through their complex action on ECM components, membrane receptor ectodomain shedding, and growth factor bioactivity.
authors.affiliation: University of Giessen Lung Center, Department of Medicine II, Aulweg 123, Room 6-11, D-35392 Giessen, Germany.
authors.forename: Julie
authors.initials: J
authors.lastname: Ryu
authors.forename: Alfin G
authors.initials: AG
authors.lastname: Vicencio
authors.forename: Michael E
authors.initials: ME
authors.lastname: Yeager
authors.forename: Michael
authors.initials: M
authors.lastname: Kashgarian
authors.forename: Gabriel G
authors.initials: GG
authors.lastname: Haddad
authors.forename: Oliver
authors.initials: O
authors.lastname: Eickelberg
mesh_terms: D000818:Animals; D015153:Blotting, Western; D003720:Densitometry; D015536:Down-Regulation; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D004797:Enzyme-Linked Immunosorbent Assay; D004848:Epithelium / Q000378:metabolism; D005109:Extracellular Matrix / Q000378:metabolism; D006801:Humans; D000860:Hypoxia; D007124:Immunoenzyme Techniques; D008168:Lung / Q000196:embryology* / Q000201:enzymology* / Q000378:metabolism; D020778:Matrix Metalloproteinase 2 / Q000096:biosynthesis; D061965:Matrix Metalloproteinase Inhibitors; D020782:Matrix Metalloproteinases / Q000096:biosynthesis*; D008648:Mesoderm / Q000378:metabolism; D051379:Mice; D017434:Protein Structure, Tertiary; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013045:Species Specificity; D019715:Tissue Inhibitor of Metalloproteinase-1 / Q000096:biosynthesis; D019714:Tissue Inhibitor of Metalloproteinases / Q000378:metabolism; D015854:Up-Regulation
chemical_list: D004791:Enzyme Inhibitors; D061965:Matrix Metalloproteinase Inhibitors; D019715:Tissue Inhibitor of Metalloproteinase-1; D019714:Tissue Inhibitor of Metalloproteinases; D020782:Matrix Metalloproteinases; D020778:Matrix Metalloproteinase 2