Anti-glycation activities of methyl gallate in vitro and in human explants.

ABSTRACT

BACKGROUND: The build-up of advanced glycation end products (AGEs) is one of important factor of skin aging. Natural compounds with anti-glycation activities might have great anti-aging potential. AIMS: The objective of this study was to evaluate an anti-glycation effects of methyl gallate as a potent ingredient for anti-aging. METHODS: We first evaluated the AGEs inhibitory ability of methyl gallate in BSA/glucose system. Levels of Nε-CML and carbonyl contents were also measured in BSA/glucose system. To further investigate if methyl gallate could prevent glycation in full-thickness human skin explants. Glycation action was determined by the observation of the general morphology of dermis and epidermis structures and FBN-1 and of CML immunostaining. In an in-vivo study, primary irritation test was also performed to ensure the safety of methyl gallate for human skin. RESULTS: It is known that methyl gallate can suppress glycation reaction between BSA and glucose. Methyl gallate also has a remarkable potential to reduce the oxidation of proteins. Furthermore, the anti-glycation activity of methyl gallate has been confirmed in a human skin ex-vivo model. Methyl gallate decreased the expression of CML but stimulated the expression of FBN-1 compared with MGO treatment. In an in-vivo study, methyl gallate (0.1%) did not cause any skin irritation, suggesting that methyl gallate could be used as an active ingredient in cosmetics. CONCLUSION: Our results showed that methyl gallate could protect against glucose-mediated glycation in vitro. Furthermore, methyl gallate significantly prevented glycation in living human skin explants. Due to these beneficial effects, methyl gallate can be used to prevent or manage AGE-mediated skin aging.