Muscle comprises 45 percent of our total body weight and has extremely important functions. It allows us to move, it makes the heart pump, controls opening and closing of passageways such as mouth, eyelids, pupils, and it helps us use and store large amounts of glucose. Muscle is a very resilient tissue which shows remarkable capacity for regeneration in response to injuries, tears and laceration.
However, despite its resiliency and regenerative capabilities, large injuries to the muscle and some chronic degenerative diseases can cause muscle loss, which becomes irreversible. Irreversible loss of muscle can be dangerous. Several studies link loss of muscle mass to premature death. In a recent article published in the journal of Proceedings of the National Academy of Sciences, tissue engineers have reported that they have grown a living muscle in the lab which can repair itself. The engineered muscle is made of fibers that contain gaps allowing muscle stem cells to grow, which is what allows self-healing. When implanted into mice, the engineered muscle integrates well into the surrounding tissue. The fibers of this engineered muscle are able to contract as well as the native animal muscle fibers and remarkably are able to repair themselves.
Scientists have demonstrated the self-healing ability of the engineered muscle in the video below. Muscle was engineered to emit fluorescence upon contraction, which allowed researchers to see more fluorescence as muscles grew inside the animal. It has previously been shown that muscle created in the laboratory looks and behaves similar to the muscle in the human body. However, these researchers have taken tissue engineering to a whole new level when they implanted the engineered muscle into mice which then continued to function as if it was a native muscle. There is great hope that tissues engineered in this way can transform the face of regenerative medicine.
Mark Juhas, George C. Engelmayr, Jr.a, Andrew N. Fontanella, Gregory M. Palmer and Nenad Bursac, Biomimetic engineered muscle with capacity forvascular integration and functional maturation in vivo, PNAS, 2014 Apr 15;111(15):5508-13
Nina Zizco, Phd student at CERG