What is 'tissue rejuvenation'?
We are made of tissues. And therefore, the process of rejuvenation of the human body is tissue rejuvenation. It's the repair of the structure of tissues and therefore in sum the repair of the overall body. The restoration of the structure of tissues and therefore the body to the state that it was in at a younger age. Now, tissue rejuvenation can be done in a number of ways. One way is simply by tissue replacement. So for example, the whole field of tissue engineering revolves around the idea of constructing outside the body an organ, like the liver for example that needs to be replaced, and then putting the whole liver back in replacement of the one that may have become diseased or old. And one could imagine that with most of our tissues. The one tissue for which that approach would rather defeat the object is the brain. And so, it's not a complete solution. So, tissue rejuvenation also includes the repair of organs by the replacement not of the whole organ in one go but rather of just the cells or even sub cellular components that have become damaged. So for example, stem cells therapy is an aspect of tissue rejuvenation where you put in cells that divide, differentiate and develop to replace cells that have become diseased and dying.
