Date(s) - 10/30/2017
We have previously shown that the spiny mouse (Acomys) can completely regenerate large skin wounds by replacing the epidermis, dermis, hair follicles, sebaceous glands, adipose tissue, smooth muscle and skeletal muscle of the panniculus carnosus. There is no fibrosis and no scarring following this type of wound and possible reasons for this include a vastly reduced cytokine storm and a reduced number of macrophages compared to the scarring wounds of Mus. We have now asked whether these same phenomena can be seen following damage to other organs and tissues of the Acomys body including skeletal muscle, the heart and the spinal cord. In each of these cases there is a vastly reduced level of fibrosis following tissue damage which allows regeneration to take place. Strikingly, even the heart can regenerate following myocardial infarction. We suggest that this unique rodent may present us with an opportunity for understanding the molecular basis of fibrosis and how to prevent its occurrence in other mammals such as humans.
Dr. Maden’s research is focused on understanding the cellular and molecular regulation of tissue and organ regeneration using several different model systems. This work is based on the principle that regeneration recapitulates development, and, by studying the signaling pathways utilized in development, he hopes to induce regeneration in non-regenerating systems. Dr. Maden has studied various systems of the body: the nervous system, the limb, and the lung, and evaluated the role that a crucial signaling molecule, retinoic acid (RA), plays in the development of these organs. Following this development to regeneration principle, he has had considerable success at inducing regeneration in non-regenerating mammals by administering RA. Similarly, by examining how signaling pathways are regulated in a naturally regenerating model organism, such as the axolotl (an amphibian with remarkable powers of organ regeneration), he can compare the molecular processes involved in regeneration to non-regenerating repair in a mammal. This helps us understand where the two processes diverge. Most recently, however, Dr. Maden discovered there is an adult mammal that can regenerate, the spiny mouse. It can repair full thickness skin wounds, replace hairs and heal without scarring; it can regenerate after ear punches and burn wounds; it can recover from myocardial infarction and has improved recovery from spinal cord damage. This has now become the focus of his regeneration studies.