Temporal analysis of vascular smooth muscle cell elasticity and adhesion reveals oscillation waveforms that differ with aging

Aging Cell

Yi Zhu¹  Hongyu Qiu²  Jerome P. Trzeciakowski³  Zhe Sun¹  Zhaohui Li¹  Zhongkui Hong¹  Michael A. Hill¹  William C. Hunter²  Dorothy E. Vatner²  Stephen F. Vatner² 

[1] Dalton Cardiovascular Res Center and Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, MO 65211, USA;Department of Cell Biology and Molecular Medicine, UMDNJ-New Jersey Med School, Newark, NJ 07101, USA;Department of Systems Biology and Translational Medicine, Texas A&M University, College Station, TX 88043, USA

关键词: atomic force microscopy;    cytoskeleton;    extracellular matrix adhesion;    fibronectin;    force measurement;    integrins;    mechanotransduction;    vascular smooth muscle cell contractile function;    Young’s modulus;   

DOI  :  10.1111/j.1474-9726.2012.00840.x

来源: Wiley

【 摘 要 】

Summary

A spectral analysis approach was developed for detailed study of time-resolved, dynamic changes in vascular smooth muscle cell (VSMC) elasticity and adhesion to identify differences in VSMC from young and aged monkeys. Atomic force microscopy (AFM) was used to measure Young’s modulus of elasticity and adhesion as assessed by fibronectin (FN) or anti-beta 1 integrin interaction with the VSMC surface. Measurements demonstrated that VSMC cells from old vs. young monkeys had increased elasticity (21.6 kPa vs. 3.5 kPa or a 612% increase in elastic modulus) and adhesion (86 pN vs. 43 pN or a 200% increase in unbinding force). Spectral analysis identified three major frequency components in the temporal oscillation patterns for elasticity (ranging from 1.7 × 10⁻³ to 1.9 × 10⁻² Hz in old and 8.4 × 10⁻⁴ to 1.5 × 10⁻² Hz in young) and showed that the amplitude of oscillation was larger (P < 0.05) in old than in young at all frequencies. It was also observed that patterns of oscillation in the adhesion data were similar to the elasticity waveforms. Cell stiffness was reduced and the oscillations were inhibited by treatment with cytochalasin D, ML7 or blebbistatin indicating the involvement of actin–myosin-driven processes. In conclusion, these data demonstrate the efficacy of time-resolved analysis of AFM cell elasticity and adhesion measurements and that it provides a uniquely sensitive method to detect real-time functional differences in biomechanical and adhesive properties of cells. The oscillatory behavior suggests that mechanisms governing elasticity and adhesion are coupled and affected differentially during aging, which may link these events to changes in vascular stiffness.

【 授权许可】

Unknown   
© 2012 The Authors. Aging Cell © 2012 Blackwell Publishing Ltd/Anatomical Society of Great Britain and Ireland