Background: Tendon is composed of connective tissue, is able to retract with high tensile
force, and plays a significant role in musculoskeletal motion. However, inappropriate physical training
or accidents often result in tendon injuries. So far, the functional healing of injured tendon is still a
great challenge in orthopedics. Mesenchymal stem cells (MSCs) are multilineage cells with the ability
to self-renew and differentiate into a variety of cell types, including tenocytes. The plasticity of MSCs
gives rise to the chance of improved healing of injured tendons and even tissue-engineered tendons.
Recently, more and more works have shown that the paracrine mechanisms of MSCs also play a critical
role in driving the tendon repair process.
Objective: The purpose of this review is to summarize the current knowledge of the induction of tenogenic
differentiation of MSCs by mechanical, chemical and mechanochemical stimulations. The role of
paracrine mechanisms of MSCs during the repair of injured tendons is also discussed.
Conclusion: The multilineage potential and the paracrine effects of MSCs create the chance for improved
healing of injured tendons and even tissue-engineered tendons. The understanding of the regulation
of the two different repair mechanisms (directed differentiation and paracrine) of MSCs has
important implications for tendon repair and regeneration.