A Cranberry Extract Stimulates Procollagen I Release and Expression After UV Radiation in a 3D Skin Model

Objectives: The purpose of this study is to evaluate the potential photoprotective effects of a cranberry extract containing proanthocyanins, phenolic acids, and anthocyanins in a full thickness reconstructed human skin model (FTSK). Methods: The effects of a cranberry extract (20 ug/mL) on the release and expression of procollagen I, a precursor to collagen I (main protein structure of human skin( were assessed in FTSK treated with repetitive UV-irradiation (4 consecutive days with UVA(+UVB) - 6 J/cm2 (+307 mJ/mc2). The skin model corresponds to the two main human skin components (epidermis and dermis). These effects were also tested on cranberry (poly)phenol metabolites generated during in vitro hepatocyte incubation. Results: Multiple irradiations of the FTSK induced a strong inhibition of procollagen I release in reconstructed tissue when the reconstructed tissue was incubated with the cranberry extract, the effects of UV-irradiation were mitigated with a significant stimulation of procollagen I releases (p < 0.05). Of added physiological significance, this effect was observed after digestion of this extract by hepatocytes (p < 0.05)., suggesting that its metabolites could also have photoprotective effects. The cranberry extract and the cranberry (poly)phenol metabolites had no effect on procollagen I expression. Conclusions: Cranberries may have a photoprotective effect through its ability to stimulate collagen synthesis via procollagen I release.