Glycation Stress and Photo-Aging in Skin

This article reviews glycation stress as a factor linked to age-related diseases and functional and structural alterations of the skin. Photo-aging and glycation stress are major causes of skin deterioration. Glycation occurs when a reducing sugar, such as glucose or fructose, combines with a protein in a non-enzymatic reaction forming a glycated protein. Further reactions form advanced glycation end products (AGEs), which may accumulate in tissue. AGEs may also bind to a receptor for AGEs (RAGE), thus inducing inflammatory changes in skin and other tissues. The concept of glycation stress includes cellular and tissue responses to reducing sugars and aldehydes, not just to the production of AGEs. Glycation stress may be induced and affected by many factors, including exposure to ultraviolet light, which drastically intensifies AGE accumulation. AGEs modify skin collagen by reducing skin elasticity, and one result is wrinkle formation. AGEs accumulated in skin may be detected using auto-fluorescence (AF); our data from 136 healthy Japanese females shows the AF level is correlated with age. Glycation stress, and subsequently skin aging, may be reduced by managing levels of blood glucose, low-density lipoprotein cholesterol, and triglyceride through an appropriate diet, lifestyle, and intake of anti-glycation materials such as AGE generation inhibitors, AGE decomposers, and AGE receptor antagonists. Study of glycation stress may help identify new anti-aging treatments.