Decreased serum transforming growth factor-[beta]1 concentration with aging is associated with the severity of emphysema in chronic obstructive pulmonary disease

• Published in: Geriatrics & gerontology international 2013-10, Vol.13 (4), p.1069
• Main Authors: Kamio, Koichiro, Ishii, Takeo, Motegi, Takashi, Hattori, Kumiko, Kusunoki, Yuji, Azuma, Arata, Gemma, Akihiko, Kida, Kozui
• Format: Article
• Language: English
• Subjects: Aging; Chronic obstructive pulmonary disease; Emphysema; Proteins
• ISSN: 1444-1586; 1447-0594
• DOI: 10.1111/ggi.12031

Aim: Age-associated changes of the lung might increase pathogenetic susceptibility to chronic obstructive pulmonary disease (COPD). Decrement in serum transforming growth factor (TGF)-[beta]1 concentration is reported in elderly people. As impaired TGF-[beta]1 signaling could cause emphysema-like changes, we hypothesized that decreased TGF-[beta]1 with aging is correlated with emphysema. Methods: Symptomatic patients with or without COPD and healthy normal subjects without COPD were recruited (COPD, n=182; smoking controls, n=73; normal, n=26). We investigated the correlation between TGF-[beta]1 and extent of emphysema and airway wall thickness, which were defined as the percentage of low-attenuation area (LAA%) and large airway wall area (WA%) on pulmonary high-resolution computed tomography, respectively. The correlation of pulmonary function test parameters and TGF-[beta]1 was evaluated. TGF-[beta]1 was determined by enzyme-linked immunosorbent assay. Results: TGF-[beta]1 significantly decreased with age (P=0.0009). When the correlation between age and TGF-[beta]1 was analyzed in each group, a significant inverse correlation was found in COPD patients and smoking controls (P=0.0095 and 0.0132, respectively), whereas no correlation was observed in healthy older adults. Among COPD patients with severe emphysema, LAA% was inversely correlated with TGF-[beta]1 (n=89, P=0.0104), whereas WA% and pulmonary function test parameters were not. Conclusions: Although no correlation was found between TGF-[beta]1 and the severity of COPD, TGF-[beta]1 significantly decreased as emphysema became more severe. Age-related decrease of TGF-[beta]1 in COPD might be associated with emphysematous alterations of the lungs in elderly subjects.[PUBLICATION ABSTRACT]