Fibulin-5 protein is reduced in the lung of patients with spontaneous pneumothorax who are under 25 years old.
OBJECTIVE
To clarify whether fibulins-5 is associated with primary spontaneous pneumothorax (PSP) in young PSP patients.


METHODS
Forty-six surgically resected, fresh lung specimens were used. Patients were divided into 3 groups: younger than 25 years with pneumothorax (group Y), 25 years or older with pneumothorax (group O), and without pneumothorax (group C). Chest X-ray, computed tomography data, height/width ratio (H/W) and anteroposterior/transverse diameter ratio (a/b) were measured. Elastica van Gieson staining and immunofluorescence staining for fibulin-5 were performed. Fibulin-5 mRNA expression and protein levels were measured by real-time PCR and western blotting. Direct sequences of the fibulin-5 gene in PSP patients were performed.


RESULTS
The mean H/W ratio in group Y was significantly larger than that in the other groups (p <0.01). The mean a/b ratio in group Y was significantly smaller than that in the other groups (p = 0.02). Fibulin-5 mRNA expression was not significantly different among the groups (p = 0.64). The relative intensity of fibulin-5 protein in group Y was significantly lower than that in group O (p = 0.006), with no significant differences between groups O and C (p = 0.14).


CONCLUSIONS
We showed that fibulin-5 is reduced in patients with PSP who are younger than 25 years.
Department of Thoracic and Cardiovascular Surgery, Wakayama Medical University, Wakayama, Wakayama, Japan. mitsu@wakayama-med.ac.jp
Yoshimitsu
Y
Hirai
Yasuteru
Y
Muragaki
Shunji
S
Itoh
Kosuke
K
Oikawa
Masanobu
M
Juri
Tomohiro
T
Kondo
Yoshitaka
Y
Okamura
D000293:Adolescent; D000328:Adult; D000368:Aged; D000704:Analysis of Variance; D015153:Blotting, Western; D016022:Case-Control Studies; D016009:Chi-Square Distribution; D015536:Down-Regulation; D016326:Extracellular Matrix Proteins / Q000032:analysis* / Q000235:genetics; D005260:Female; D006801:Humans; D008168:Lung / Q000737:chemistry* / Q000000981:diagnostic imaging / Q000601:surgery; D008297:Male; D008856:Microscopy, Fluorescence; D008875:Middle Aged; D011030:Pneumothorax / Q000000981:diagnostic imaging / Q000235:genetics / Q000378:metabolism* / Q000601:surgery; D012333:RNA, Messenger / Q000032:analysis; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D014057:Tomography, X-Ray Computed; D055815:Young Adult
D016326:Extracellular Matrix Proteins; C492373:FBLN5 protein, human; D012333:RNA, Messenger