Determining nail consistency by quantification of type I keratins

Abstract

Nail consistency is a little studied characteristic of the nail plate. Numerous factors can influence its determination, including the anatomy of the nail apparatus, the structure of the nail plate, and the type and quantity of keratins present. To study the relationship between nail consistency and the expression level of type I keratins, a sample was chosen of 32 individuals in the same age group (49.94 ± 3.38 years), 18 with hard consistency nails and 14 with soft consistency nails, with the same number of individuals for each gender. Two buffers with different concentrations of reducing agent (50mM and 200mM) and two antibodies to various type I keratins were analyzed by immunoblotting. The mean extracted protein concentration at 50mM was significantly higher than the concentration at 200mM (p-value<0.001). The expression level obtained with the AE13 antibody did not vary with gender or nail consistency (p-values≥0.942). With the cytokeratin 17 antibody (CTK17), no differences were found by gender (p-value=0.341). However, significant differences were established between hard-consistency and soft-consistency nails (p-values≤0.007) for the two concentrations, and between concentrations for soft consistency nails (p-value=0.001). Hard-consistency nails had a higher expression level of K17. Adding to the elemental analysis between layers and the flexural behavior of the nail plate studied reported in previous studies, this work demonstrates that nail consistency also depends