Shear stress-induced mechanotransduction protein deregulation and vasculopathy in a mouse model of progeria.

Abstract

INTRODUCTION:

A mouse model of progeria derived by insertion of the human mutant LMNA gene (mLMNA), producing mutant lamin A, shows loss of smooth muscle cells in the media of the ascending aorta. We hypothesized that high shear stress, in the presence of mutant lamin A, induces this vasculopathy and tried to define the molecular and cellular basis for aortic vasculopathy.

METHODS:

Ascending and descending aortas from wild type (WT) and mLMNA+ mice were compared using proteomics, Western blots, PCR and immunostaining. To determine whether high fluidic shear stress, known to occur in the ascending aorta, contributed to the vasculopathy, we exposed descending aortas of mLMNA+ mice, with no apparent vasculopathy, to 75 dynes/cm2 shear stress for 30 minutes using a microfluidic system.

RESULTS:

When the mice were one year of age, expression of several mechanotransduction proteins in the ascending aorta, including vimentin, decreased in mLMNA+ mice but no decrease occurred in the descending aorta. High fluidic shear stress produced a significant reduction in vimentin of mLMNA+ mice but not in similarly treated WT mice.

CONCLUSIONS:

The occurrence of mutant lamin A and high shear stress correlate with a reduction in the level of mechanotransduction proteins in smooth muscle cells of the media. Reduction of these proteins may contribute over time to development of vasculopathy in the ascending aorta in progeria syndrome.

• Authors: Minjung Song, Hong San, Stasia A Anderson, Richard O Cannon 3rd, Donald Orlic
• Journal: Stem cell research & therapy (Stem Cell Res Ther) Vol. 5 Issue 2 Pg. 41 (Mar 24 2014) ISSN: 1757-6512 [Electronic] England
• PMID: 24661531 (Publication Type: Journal Article, Research Support, N.I.H., Intramural)

Chemical References

• Intermediate Filament Proteins
• Lamin Type A
• Nuclear Proteins
• Protein Precursors
• prelamin A

Topics

• Animals
• Disease Models, Animal
• Gene Expression
• Humans
• Intermediate Filament Proteins (metabolism)
• Lamin Type A
• Mechanotransduction, Cellular
• Mice
• Muscle, Smooth, Vascular (metabolism, pathology)
• Nuclear Proteins (metabolism)
• Progeria (metabolism, pathology)
• Protein Precursors (metabolism)
• Stress, Mechanical
• Vascular Diseases (metabolism, pathology)