A novel dual-frequency loading system for studying mechanobiology of load-bearing tissue.
In mechanobiological research, an appropriate loading system is an essential tool to mimic mechanical signals in a native environment. To achieve this goal, we have developed a novel loading system capable of applying dual-frequency loading including both a low-frequency high-amplitude loading and a high-frequency low-amplitude loading, according to the mechanical conditions experienced by bone and articular cartilage tissues. The low-frequency high-amplitude loading embodies the main force from muscular contractions and/or reaction forces while the high-frequency low-amplitude loading represents an assistant force from small muscles, ligaments and/or other tissue in order to maintain body posture during human activities. Therefore, such dual frequency loading system may reflect the natural characteristics of complex mechanical load on bone or articular cartilage than the single frequency loading often applied during current mechanobiological experiments. The dual-frequency loading system is validated by experimental tests using precision miniature plane-mirror interferometers. The dual-frequency loading results in significantly more solute transport in articular cartilage than that of the low-frequency high-amplitude loading regiment alone, as determined by quantitative fluorescence microscopy of tracer distribution in articular cartilage. Thus, the loading system can provide a new method to mimic mechanical environment in bone and cartilage, thereby revealing the in vivo mechanisms of mechanosensation, mechanotransduction and mass-transport, and improving mechanical conditioning of cartilage and/or bone constructs for tissue engineering.
Tianjin Key Laboratory of the Design and Intelligent Control of the Advanced Mechatronical System, Tianjin University of Technology, Tianjin 300384, China; Cell and Molecular Biology Laboratory, Department of Orthopaedics, Alpert Medical School of Brown University/Rhode Island Hospital, Providence, RI, USA. Electronic address: zhang_chunqiu@126.com.
Chunqiu
C
Zhang
Tianjin Key Laboratory of the Design and Intelligent Control of the Advanced Mechatronical System, Tianjin University of Technology, Tianjin 300384, China.
Lulu
L
Qiu
Tianjin Key Laboratory of the Design and Intelligent Control of the Advanced Mechatronical System, Tianjin University of Technology, Tianjin 300384, China.
Lilan
L
Gao
Cell and Molecular Biology Laboratory, Department of Orthopaedics, Alpert Medical School of Brown University/Rhode Island Hospital, Providence, RI, USA.
Yinjie
Y
Guan
Tianjin Key Laboratory of the Design and Intelligent Control of the Advanced Mechatronical System, Tianjin University of Technology, Tianjin 300384, China.
Qiang
Q
Xu
Tianjin Key Laboratory of the Design and Intelligent Control of the Advanced Mechatronical System, Tianjin University of Technology, Tianjin 300384, China.
Xizheng
X
Zhang
Cell and Molecular Biology Laboratory, Department of Orthopaedics, Alpert Medical School of Brown University/Rhode Island Hospital, Providence, RI, USA. Electronic address: Qian_chen@brown.edu.
Qian
Q
Chen
D000818:Animals; D055592:Biophysical Phenomena; D002358:Cartilage, Articular / Q000502:physiology*; D005269:Femur / Q000502:physiology*; D007368:Interferometry; D008856:Microscopy, Fluorescence; D013552:Swine; D023822:Tissue Engineering; D016474:Weight-Bearing
Cartilage; Dual-frequency; Loading system; Mechanobiology; Solute transport