Effect of regioisomers of hydroxystearic acids as peroxisomal proliferator-activated receptor agonists to boost the anti-ageing potential of retinoids.

Introduction: We report on the in vitro and ex vivo effects of chiral (R)-10-hydroxystearic acid (10-HSA) compared with other mono-hydroxystearic acid regioisomers and stearic acid (SA) together with its benefit when combined with retinol.

Methods: Following treatment with hydroxystearic acids peroxisomal proliferator-activated receptor alpha (PPARα) activity was determined in a luciferase reporter gene assay, collagen type I was assessed in primary human dermal fibroblasts by immunohistochemistry, modification of the intracellular fibroblast collagen proteome was studied by mass-spectrometry-based proteomics and collagen type III was assessed by immunohistochemistry on human ex vivo skin.

Results: 10-HSA was the most effective PPARα agonist (15.