Epidermal fatty acid-binding protein is increased in rat lungs following in vivo treatment with keratinocyte growth factor.
Exogenous application of keratinocyte growth factor protects the lung against a variety of injurious stimuli. KGF-treatment leads to pronounced hyperplasia of alveolar epithelial type II cells and to stabilization of surfactant homeostasis after lung injury. Epidermal fatty acid-binding protein is involved in the synthesis of surfactant phospholipids and acts as an antioxidant scavenging reactive lipids. We treated adult rats with recombinant human keratinocyte growth factor (Palifermin) via intratracheal instillation and analyzed the expression of epidermal fatty acid-binding protein mRNA and protein by quantitative RT-PCR, immunoblotting as well as immunohistochemistry. Keratinocyte growth factor-treatment in vivo leads to an increased expression of epidermal fatty acid-binding protein mRNA and protein in the total lung. Epidermal fatty acid-binding protein mRNA expression per alveolar epithelial type II cell remains constant as shown in isolated type II cells. Epidermal fatty acid-binding protein immunoreactivity is seen in most if not all hyperplastic alveolar epithelial type II cells, and is mainly localized to the cytoplasm. The increase in epidermal fatty acid-binding protein gene expression associated with type II cell hyperplasia might contribute to the molecular mechanisms mediating lung protection by keratinocyte growth factor.
Grau
Veronika
V
Laboratory of Experimental Surgery, Department of General and Thoracic Surgery, University of Giessen Lung Center, Justus-Liebig-University Giessen, Rudolf-Buchheim-Str. 7, D-35385 Giessen, Germany. Veronika.Grau@chiru.med.uni-giessen.de
Garn
Holger
H
Holler
Julia
J
Rose
Frank
F
Blöcher
Sonja
S
Hirschburger
Markus
M
Fehrenbach
Heinz
H
Padberg
Winfried
W
D000818:Animals; D004817:Epidermis / Q000187:drug effects* / Q000378:metabolism; D005136:Eye Proteins / Q000235:genetics / Q000378:metabolism*; D050556:Fatty Acid-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D051523:Fibroblast Growth Factor 7 / Q000378:metabolism / Q000494:pharmacology*; D006801:Humans; D008168:Lung / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D008297:Male; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000378:metabolism*; D011663:Pulmonary Surfactants / Q000378:metabolism; D051381:Rats
D005136:Eye Proteins; C107356:Fabp5 protein, rat; D050556:Fatty Acid-Binding Proteins; D009419:Nerve Tissue Proteins; D011663:Pulmonary Surfactants; D051523:Fibroblast Growth Factor 7