Harnessing the skin-thyroid connection for wound healing: a prospective controlled trial in guinea pigs.

Different elements of the hypothalamic-pituitary-thyroid axis have been found to be implicated in the normal physiology of the human skin. Their effects on wound healing and hair growth in rats have been described previously. There is close homology between the thyroid hormone receptors in humans and guinea pigs. To assess the effect of different doses of topical 3,3',5-triiodo-L-thyronine (T3) and recombinant human thyroid-stimulating hormone (TSH) on wound healing in guinea pigs. Wounds were dressed every other day for 7 days, during which clinical measurements of the wounded areas were performed. Histological examination was performed at the end of the study. Application of high and low concentrations of topical T3 but not TSH demonstrated a significant dose-dependent reduction in the wound surface area through a process of contraction. The main significant histological result was an increase in the hair-follicle count. Topical T3 enhances wound healing in guinea pigs, primarily by wound contraction. As this is a critical stage in healing of chronic ulcers, topical T3 could be a useful treatment for wounds.