Impact of mechanical stimulation on tendon tissue in a bioreactor system

[Truncated abstract] Tendons are force-transmitting tissues connecting muscle to bone. Because of this physiological function, biomechanics plays an essential role in maintaining tendon homeostasis. Indeed tenocytes have the ability to sense and respond to different mechanical loads by remodeling the tendon tissue. Studies reported that load deprivation can cause tendinopathy-like morphology such as disorientated collagen fibers and rounded cell nuclei, while mechanical overloading can result in tears and rupture of the tendon. In tendon engineering studies, mechanical stimulation has been shown to improve the cell viability, proliferation, and neo-tendon structure and mechanical properties. Obviously, the biomechanical environment has various effects on tendon tissue; and yet the specific effects of different loading conditions on tendon have not been well elucidated. Mechanical loading is both a source of degradation (e.g. through damage and indirectly through protease activity) and a stimulus for tissue synthesis/repair. The hypothesis of this PhD project is that there is some optimal mechanical load to maintain or restore functional tendon tissue in a bioreactor.

Firstly, in order to study the mechanical stimulation on tendon tissue, a functional bioreactor is necessary. A uniaxial bioreactor was designed and fabricated. This bioreactor system is able to provide pre-programmable mechanical simulation and sterilized environment for a maximum 6 individual tendons simultaneously.