Age and sex variation in lipid composition of human fingernail plates

In contrast to epidermal lipid metabolism, the lipid biochemistry of nails has yet been poorly investigated. Our purpose was to define a reference population of healthy individuals as a base for the better understanding of nail diseases and age-induced changes. Therefore, we developed a method of processing and extracting the nail plates enabling us to assess the most relevant epidermal lipid classes by HPTLC. Our study revealed that nail plate lipid composition varies with age and sex: the lipid composition of the fertile years shows distinct profiles compared to that of childhood and old age, suggesting an influence of sex hormones on nail lipogenesis. Our results open the possibility in the future of an easier comparison between healthy and diseased nails and enable us to investigate factors influencing nail lipid composition such as drugs, metabolic diseases, toxic agents, cosmetics and nail therapeutics.