Laminar high shear stress up-regulates type IV collagen synthesis and down-regulates MMP-2 secretion in endothelium. A quantitative analysis.
Remodeling of endothelial basement membrane is important in atherogenesis. Since little is known about the actual relationship between type IV collagen and matrix metalloprotease-2 (MMP-2) in endothelial cells (ECs) under shear stress by blood flow, we performed quantitative analysis for type IV collagen and MMP-2 in ECs under high shear stress. The mRNA of type IV collagen from ECs exposed to high shear stress (10 and 30 dyn/cm(2)) had a higher expression compared to ECs exposed to a static condition or low shear stress (3 dyn/cm(2)) (P < 0.01). (3)H-proline uptake analysis and fluorography revealed a remarkable increase of type IV collagen under high shear stress (P < 0.01). In contrast, zymography revealed that exposing to high shear stress, however similar positivity was leveled in the intracellular MMP-2 in the control and high shear stress-exposed ECs, reduced the secretion of MMP-2 in ECs. The results of Northern blotting, gelatin zymography and monitoring the intracellular trafficking of GFP-labeled MMP-2 revealed that MMP-2 secretion by ECs was completely suppressed by high shear stress, but the intracellular mRNA expression, protein synthesis, and transport of MMP-2 were not affected. In conclusion, we suggest that high shear stress up-regulates type IV collagen synthesis and down-regulates MMP-2 secretion in ECs, which plays an important role in remodeling of the endothelial basement membrane and may suppress atherogenesis.
Yamane
Tetsu
T
Department of Human Pathology, School of Medicine, University of Yamanashi, Yamanashi, Japan.
Mitsumata
Masako
M
Yamaguchi
Noriko
N
Nakazawa
Tadao
T
Mochizuki
Kunio
K
Kondo
Tetsuo
T
Kawasaki
Tomonori
T
Murata
Shin-ichi
S
Yoshida
Yoji
Y
Katoh
Ryohei
R
D000818:Animals; D002417:Cattle; D024141:Collagen Type IV / Q000096:biosynthesis*; D015536:Down-Regulation / Q000235:genetics*; D042783:Endothelial Cells / Q000166:cytology / Q000201:enzymology; D004727:Endothelium / Q000201:enzymology*; D004780:Environment, Controlled; D015971:Gene Expression Regulation, Enzymologic; D049452:Green Fluorescent Proteins / Q000378:metabolism; D042541:Intracellular Space / Q000378:metabolism; D020778:Matrix Metalloproteinase 2 / Q000235:genetics / Q000378:metabolism*; D021381:Protein Transport; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D013314:Stress, Mechanical; D015854:Up-Regulation / Q000235:genetics*
D024141:Collagen Type IV; D012333:RNA, Messenger; D049452:Green Fluorescent Proteins; D020778:Matrix Metalloproteinase 2