Growth factors gene expression in the developing lung

• Published in: Acta Paediatrica 2007-07, Vol.96 (7), p.1015-1020
• Main Authors: Mager, Edward M., Renzetti, Gabriele, Auais, Alexander, Piedimonte, Giovanni
• Format: Article
• Language: English
• Subjects: Animals; Animals, Newborn; Asthma; Biological and medical sciences; Bronchopulmonary dysplasia; Chronic obstructive pulmonary disease, asthma; Epidermal Growth Factor - genetics; Epidermal Growth Factor - metabolism; Gene Expression; General aspects; Genetic Predisposition to Disease; Growth factors; Lung - embryology; Lung - physiology; Lung development; Lung Diseases - genetics; Medical sciences; Pneumology; Polymerase Chain Reaction - methods; Rats; Rats, Inbred F344; Real-time PCR; Respiratory system : syndromes and miscellaneous diseases; Transforming Growth Factor beta - genetics; Transforming Growth Factor beta - metabolism; Vascular Endothelial Growth Factor A - genetics; Vascular Endothelial Growth Factor A - metabolism
• ISSN: 0803-5253; 1651-2227
• DOI: 10.1111/j.1651-2227.2007.00332.x

Aim: This is the first systematic study using quantitative real‐time PCR to analyze and compare the expression profiles for critical members of the epidermal growth factor (EGF), transforming growth factor β (TGFβ), and vascular endothelial growth factor (VEGF) families in developing rat lungs. Methods: mRNA expression was quantified at embryonic (E) day 15, 17, 19, 21, and postnatal age 1 day, 2 weeks, 12 weeks. Results: EGF and EGFR increased during gestation and development, then decreased in adulthood, whereas TGFα was highest at birth and remained unchanged afterwards. All TGFβ isoforms increased slightly during pregnancy, reached highest expression during development, and returned to neonatal levels in adulthood. TGFβRI and TGFβRII patterns were similar to TGFβ2 and TGFβ1 respectively, whereas TGFβRIII expression was lowest at the postnatal time points. VEGF164 and VEGF120 showed a steady increase up to 2 weeks and declined at 12 weeks, whereas highest VEGF188 expression occurred at 12 weeks. VEGF‐A receptors expression paralleled the summation of all three isoforms, increasing steadily with age. Conclusion: Expression of growth factors in the developing lung is characterized by highly regulated distinctive patterns that may be critical to understand the early origin and progression of pulmonary diseases in childhood as well as in adulthood. Quantitative real‐time PCR analysis revealed several differences compared to previously reported expression patterns defined with older methodologies.