Tendons, which connect muscles and bones, are a dense collagenous tissue populated by specialized fibroblasts. These fibroblasts are periodically subjected to mechanical stimulation, which is important in maintaining tissue homeostasis and triggering adaptive tissue responses. Surprisingly, the mechanisms which underpin the response of tendon cells to various types of mechanical stimulation (substrate strain vs fluid flow; integrin-mediated signaling vs stretch-activated channels) remain largely unknown.

Background

The development of exercise programs that can improve the strength of muscles and bones has improved our society’s ability to age successfully. Exercise scientists and physical activity proponents, however, often overlook tendons. A recent series of studies has revealed that if given a specific training stimulus, tendons can become stronger and improve their energy storage capacity. The underlying mechanisms are not fully understood, but are thought to involve the production of new collagen fibres by local tendon fibroblasts tenocytes) in response to stimulation of integrin receptors and/or stretch activated ion channels.

Summary of the Scientific Approach

Tendon mechanobiology is being examined in vitro using a magnetic stimulation system (MICA) capable of activing integrins, a class of transmembrane receptors with known mechanosensory function. The resulting modulation of cell signaling pathways will be studied.