When comparing efficacies of growth factors versus peptides, certain functional nuances need to be borne in mind when testing gene responses, particularly in laboratory environments. In that context, a recent study4 attempted to compare various formulations including growth factor- and non-growth factor-based skin care products, assessing their biologic activity based on gene expression responses.
Major limitations were identified related to this study, which included the following:
- A single test period was examined (24 hours), which, while this time frame may be suited to growth factor stimulation, peptides behave differently and have been demonstrated in many cases to have maximal activity in gene expression at 48, 72, and even longer time periods.
- When selecting controls, water may be ideal for certain aqueous formulations but for non-aqueous anhydrous preparations such as (Alastin Regenerating Skin Nectar), this provides potential inaccuracies.
- Finally, although the skin culture EFT model selected has been successfully used as a surrogate for human studies, there are inherent limitations to testing combined cell lines. Although transcription (cell commands) signaling may be demonstrated, the true proof of efficacy often resides in the translational capacity of the product, that relating to new cell and protein regeneration. This is best represented by histological assess- ments of biopsies which take into account the ability of the actives to penetrate skin in a real world environment.
In an effort to address some of the limitations addressed above, a study was designed to test Alastin Skincare Regenerating Skin Nectar, ensuring analysis at two time points, selecting appropriate baseline control comparators, and using a broad panel of genes (Genemarkers Standard Skin Panel) covering a range of important biological functions in skin rather than a few selected genes.