Abstract
Accumulation of advanced glycation end products (AGEs) in skin tissues due to glycative stress is one of the factors that accelerate skin aging, including decreased elasticity and loss of texture. Suppression of glycative stress is called anti-glycation or glycation care. For anti-glycation of the skin, there are treatments from the inside of the body such as diet and approaches from the outside of the body such as skin care preparations. Furthermore, anti-glycation includes the suppression of postprandial hyperglycemia, suppression of glycation reactions, and decomposition and excretion of AGEs. Various plant materials have been shown to have anti-glycation effects. However, the glycation reaction in the body that leads to the formation of AGEs is a complex multi-pathway reaction, and it is thought that a multi-component approach may be useful. This study was conducted to evaluate the anti-glycation effects of five plant extract complexes (sea buckthorn fruit, Chinese blackberry tea, tea plant leaves, loquat leaves, and rosemary leaves) that can be used in skin care formulations. To evaluate the anti-glycation effects of plant extract complex (PEC) on skin, we examined its inhibitory effects on glycation reaction, AGE cross-link cleavage, inhibitory formation of glycated protein cross-link, glycated protein cross-link cleavage, and antioxidant activity. As results, PEC inhibited the production of fluorescent AGEs in protein glycation models of human serum albumin (HSA), collagen, and keratin. PEC also inhibited the production of pentosidine, Nε-(carboxymethyl)lysine (CML), 3-deoxyglucosone (3DG), and glyoxal (GO) in a keratin-glucose glycation model. Furthermore, PEC has AGE cross-link-cleavage effect, inhibits protein cross-link formation in a lysozyme-glucose glycation cross-linking model, and degrades proteins dimerized by glycation. PECs may be useful in preventing glycation of skin by suppressing AGE accumulation in skin proteins and preventing functional deterioration caused by the formation of glycated protein cross-links.
