|
1
|
Yang H, Schmidt LP, Wang Z, Yang X, Shao Y, Borg TK, Markwald R, Runyan R, Gao BZ. Dynamic Myofibrillar Remodeling in Live Cardiomyocytes under Static Stretch. Sci Rep 2016; 6:20674. [PMID: 26861590 PMCID: PMC4748238 DOI: 10.1038/srep20674] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2015] [Accepted: 01/11/2016] [Indexed: 12/21/2022] Open
Abstract
An increase in mechanical load in the heart causes cardiac hypertrophy, either physiologically (heart development, exercise and pregnancy) or pathologically (high blood pressure and heart-valve regurgitation). Understanding cardiac hypertrophy is critical to comprehending the mechanisms of heart development and treatment of heart disease. However, the major molecular event that occurs during physiological or pathological hypertrophy is the dynamic process of sarcomeric addition, and it has not been observed. In this study, a custom-built second harmonic generation (SHG) confocal microscope was used to study dynamic sarcomeric addition in single neonatal CMs in a 3D culture system under acute, uniaxial, static, sustained stretch. Here we report, for the first time, live-cell observations of various modes of dynamic sarcomeric addition (and how these real-time images compare to static images from hypertrophic hearts reported in the literature): 1) Insertion in the mid-region or addition at the end of a myofibril; 2) Sequential addition with an existing myofibril as a template; and 3) Longitudinal splitting of an existing myofibril. The 3D cell culture system developed on a deformable substrate affixed to a stretcher and the SHG live-cell imaging technique are unique tools for real-time analysis of cultured models of hypertrophy.
Collapse
Affiliation(s)
- Huaxiao Yang
- Department of Bioengineering, Clemson University, Clemson, SC, USA
| | - Lucas P Schmidt
- Department of Bioengineering, Clemson University, Clemson, SC, USA
| | - Zhonghai Wang
- Department of Bioengineering, Clemson University, Clemson, SC, USA
| | - Xiaoqi Yang
- Department of Bioengineering, Clemson University, Clemson, SC, USA
| | - Yonghong Shao
- Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Optoelectronic Engineering, Shenzhen University, Shenzhen, China
| | - Thomas K Borg
- Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, Charleston, SC, USA
| | - Roger Markwald
- Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, Charleston, SC, USA
| | - Raymond Runyan
- Department of Cellular and Molecular Medicine, University of Arizona, Tucson, AZ, USA
| | - Bruce Z Gao
- Department of Bioengineering, Clemson University, Clemson, SC, USA
| |
Collapse
|