In people and domestic animals, scarring in the skin after trauma, surgery, burns or a sports injury is an important medical problem, often resulting in unsightly aesthetics, loss of function, restriction of tissue elasticity and/or growth and adverse psychological effects.

Current treatments are strictly empirical, troublesome and unpredictable. There are no prescription medicines for the avoidance or treatment of dermal scarring. Skin wounds on early mammalian embryos cure flawlessly with no scars, whereas wounds to adult mammals are prone to scarring.

In scar treatment research, scientists are investigating the cellular and molecular differences between scar-free healing in embryonic wounds and scar-forming healing in adult wounds. Relevant differences include the inflammatory reaction, which in embryonic wounds consists of fewer numbers of less differentiated inflammatory cells. This occurrence, together with augmented levels of morphogenetic molecules involved in skin growth and morphogenesis, implies that the growth factor profile of an embryonic injury is highly different from that of an adult injury.

These experiments proved the possibility of scar-less healing in the adult subject and have lead to the identification of appropriate therapeutic targets. It has been found that effective skin care markedly improves or completely avoids scarring during adult injury healing in experimental animals. Some of these new drugs have satisfyingly completed safety and other studies, such that they have entered human clinical trials with approval from the appropriate regulatory authorities. Based on auspicious results from these volunteer studies, the leading drugs have now entered human patient-based trials e.g. in skin graft donor sites.

Proposing Solutions

The hypothesis is that evolutionary pressures have been exerted on intermediate sized, widespread, dirty wounds with considerable tissue damage e.g. bites, bruises and contusions. Modern wounds (e.g. resulting from trauma or surgery) caused by sharp instruments, are recent occurrences not previously found in nature, in which the evolutionary selected wound healing responses are somewhat useless. It has been shown that both repair with scarring and regeneration can occur within the same animal, including man, and indeed within the same tissue, thereby suggesting that they share similar mechanisms and regulators.

Consequently, by subtly altering the proportion of growth factors present in adult wound healing, we can induce adult wounds to heal flawlessly with no scars, with accelerated healing and without adverse consequences, e.g. on wound strength or wound infection rates. This implies that scarring may no longer be an inevitable sequel of modem injury or surgery, and that a fully new pharmaceutical concept to the avoidance of human scarring is now possible. Not only skin suffers from scarring; they can appear in many other tissues as well.

Thus scar-improving drugs could have widespread benefits and prevent complications in several tissues, e.g. the prevention of blindness after scarring due to eye damage, support of neuronal reconnections in the peripheral and central nervous system by the avoidance of glial scarring, recovery of normal gut and reproductive function by avoiding strictures and adhesions after damage to the gastrointestinal or reproductive tracts, and the recovery of locomotor function by avoiding scarring in tendons and ligaments.