Regulation of Nogo-B expression in the lesion of aortic aneurysms.
1. Our previous study showed that Nogo-B was highly expressed in endothelial cells and downregulated in endothelial cells following induction by lysophosphatidylcholine, which contributed to atherosclerotic lesions. However, the role of Nogo-B in the development of aortic aneurysms remains unclear. 2. In the present study, segments of thoracic aortic aneurysms (TAA) and adjacent normal thoracic aortic tissues (NTA) without aneurysmal changes were obtained from 31 patients undergoing graft surgery. The mRNA and protein expression levels of Nogo-B were measured with semiquantitative reverse transcription-polymerase chain reaction, western blotting and immunohistochemistry. 3. The results demonstrate that Nogo-B mRNA expression levels in TAA lesions decreased to 45% compared with levels in NTA lesions and that protein levels in TAA decreased to 35%. Tissue Nogo immunohistochemical staining in aortic specimens suggested the involvement of Nogo in neovascularization and smooth muscle cell proliferation. The weaker brown staining of endothelial cells in TAA lesions suggested the lower expression of Nogo-B in TAA lesions. 4. These results demonstrate that Nogo-B mRNA and protein expression are downregulated in TAA lesions. It is concluded that the reduction of Nogo-B protein expression in TAA lesions is closely correlated to the formation of aneurysm and that Nogo-B may play a protective role in the pathological process of aneurysms.
Pan
Jing-Wei
JW
Department of Cardiology, Shanghai 6th People's Hospital, Shanghai Jiaotong University, Shanghai, China.
Wei
Meng
M
Yang
Peng-Yuan
PY
Zheng
Xing
X
Li
Jing-bo
JB
Lu
Zhi-gang
ZG
Zhao
Xian-Xian
XX
Wu
Hong
H
Kang
Hui
H
Rui
Yao-cheng
YC
D001013:Aorta, Thoracic / Q000737:chemistry* / Q000473:pathology; D017545:Aortic Aneurysm, Thoracic / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D015153:Blotting, Western; D015536:Down-Regulation; D006801:Humans; D007150:Immunohistochemistry; D009185:Myelin Proteins / Q000032:analysis* / Q000235:genetics; D000070798:Nogo Proteins; D012333:RNA, Messenger / Q000032:analysis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017539:Tunica Intima / Q000737:chemistry* / Q000473:pathology
D009185:Myelin Proteins; D000070798:Nogo Proteins; D012333:RNA, Messenger; C000603199:RTN4 protein, human