Vernix Caseosa: The Ultimate Natural Cosmetic?

By: Johann W. Wiechers, PhD, JW Solutions; and Bernard Gabard, PhD, Iderma

Posted: August 31, 2009, from the September 2009 issue of Cosmetics & Toiletries.

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Barrier Formation and Wound Healing
Summarizing the discussion thus far, immediately after birth, vernix caseosa is involved in maintaining the water balance in the skin of a newborn and in that way, helps to maintain skin temperature as well as the right water activity in the skin for optimal skin barrier formation. This suggests that vernix caseosa could also have a skin repairing effect when applied to damaged skin (i.e., wounds, scars) as well as dry skin.

Wound treatment and management is an important aspect of curing hospital patients that either are admitted with existing wounds or who obtain new wounds from surgical procedures. The healing of open cutaneous wounds has been divided into three overlapping phases: inflammation, re-epithelization and wound contraction. A moist environment was found to be optimal for wound healing, particularly during the inflammatory and proliferative phases, whereas enhanced cell migration, which is part of the re-epithelization process, has also been facilitated by moist conditions.³⁰ Occlusive dressings have therefore become increasingly popular since they enhance wound healing primarily by preventing wound desiccation and by creating this moist environment.

However, when comparing fully occlusive foils to semi-occlusive foils, Schunck et al.³⁰ found that wounds treated with semi-occlusive foils reduced wound contraction but enhanced cell migration and re-epithelization without irritation. This finding matches the observations of Visscher et al., who found that wounds treated with semi-permeable membranes undergo a more rapid barrier recovery than either non-occluded wounds or wounds under complete occlusion. Coverings that produce intermediate levels of skin hydration during recovery produced the highest barrier repair rates.³¹

These results suggest that barrier repair is augmented because semi-permeable membranes provide an optimal water vapor gradient during the wound healing process. Unfortunately, the optimal water gradient for wound care was not investigated but studies in the SC have shown that there is a critical range of water activities of 80% to 95% relative humidity, which permits filaggrin proteolysis to take place.³²

The ideal water vapor transport rate through vernix caseosa and its implications for barrier repair were presented by Gunt et al. in 2002.33 The flux of water was measured as a function of time through an artificial membranec that was chosen because it had a water vapor transport profile in the same range as that of preterm infant or wounded skin.