ABSTRACT
Glycation is the non-enzymatic reaction between reducing sugars and proteins that leads to the formation of advanced glycation end products (AGEs). In vivo skin autofluorescence (lambda(ex)/lambda(em)=370/440 nm) was used as a non-invasive clinical tool to study skin AGE accumulation in healthy panellists. Using multiple linear regression analysis, it was shown that for panellists below the age of 40, glycation associated in vivo skin fluorescence intensity increased as a function of chronological age and body mass index (BMI). Above the age of 40, the fluorescence was associated to age but not to BMI, suggesting that the effect of age became dominant over BMI. Since the accumulation of AGEs is expected to affect the biomechanical properties of the skin, in vivo skin elasticity data were gathered on a second panel. It was found that skin elasticity depended on age and BMI in a similar fashion as to what we observed for the skin fluorescence data. It is hypothesised that skin AGE accumulation contributes to the loss of skin elasticity in aged and/or overweight people.
Subject(s)
Aging/physiology , Skin Physiological Phenomena , Adult , Body Mass Index , Elasticity , Female , Fluorescence , Glycation End Products, Advanced/metabolism , Glycation End Products, Advanced/physiology , Glycosylation , Humans , Middle Aged , Skin/metabolism , Skin Aging/physiology , Skin Pigmentation/physiology , Spectrometry, FluorescenceABSTRACT
The aim of this study was to develop a technique to assay for the activity of antioxidants in a finished cosmetic product. This was accomplished by adapting the Randox Assay for Total Antioxidant Status kit so that diluted samples could be evaluated by kinetic as well as end-point determinations. Using this technique, we found that a finished product had an IC(50) of 0.07 gm of product and a relative antioxidant activity concentration of 52.7 nmoles/mg.
