Vernix Caseosa: A source of natural moisturizing factors and its possible role in neonatal infant skin hydration

The 'Natural Moisturizing Factors'(NMF) are free amino acids along with the other physiological chemicals like urea, lactic acid and salts in the Stratum Corneum(SC). These soluble amino acids are generated from filaggrin and are responsible for keeping the skin moist and pliable by attracting and holding water. Shortly after birth infants sometimes exhibit symptoms of dry skin, which may be related to low amino acid levels.; At birth infants are often coated with a proteolipid film, vernix caseosa, which is generally, cleaned off soon after birth. It interfaces the developing fetus with the amniotic fluid during the last trimester of gestation. Postnatal ontogeny of the amino acids in skin and its possible presence in vernix has implications for infant skin care regimens.; Our investigation aimed at determining the amount of these soluble amino acids in infant skin at birth and comparing it to the amount in normal healthy adult skin. The results showed that the NMF amino acid content in infant foreskin reduces with increasing depth in the SC as opposed to the increasing levels of NMF amino acids in the adult skin.; A complete protein profile of vernix was determined and the NMF amino acids were quantified using reverse phase HPLC. The results suggest that the NMF amino acids are present in vernix and its profile is comparable to that in infant and adult skin.; We further determined the effect of different relative humidities on the generation of NMF amino acids in vernix. (Abstract shortened by UMI.)...