On September 20th, Dr. Williams spoke at the HAPPI Anti-Aging Conference in New Brunswick about the molecular mechanisms of skin aging. Some of the highlights from her talk include:
1) Skin aging reflects global aging, and skin aging the same way other organs do. Because skin is so visible these aging changes are readily apparent, sometimes to our chagrin.
2) Skin aging may be broken down into 2 categories: intrinsic aging and extrinsic aging. Intrinsic aging is a function of the passage of time; also known as chronological aging. Extrinsic aging is the result of environment and lifestyle, and includes sun exposure, smoking, pollution, etc. Dr. Williams emphasized that the sun is a major carcinogen and “age accelerator.”
3) Skin aging is more than just wrinkles. As we age, skin starts to thin, sag, and can hyperpigment. There is loss of subcutaneous fat, and therefore skin can bruise more easily. Skin gets dehydrated, and therefore prone to eczema (dryness, cracking). Eczematous skin is prone to infection and does not heal well after any trauma, etc.
4) On a molecular level there are several theories of aging that all work in tandem:
mitochondrial DNA mutations
5) All of the above lead to Cellular Senescence. Senescent cells are cells that are no longer replicating. When skin cells become senescent they stop replicating, hence skin ages. A common misconception is that senescent cells are resting, and not active. To the contrary, Dr. Williams talked about the “Senescence Associated Secretory Phenotype” which is a mixture of pro-inflammatory molecules that these “resting” cells are very busy making. All these cytokines lead to chronic inflammation, which has harmful effects.
6) Diabetics have accelerated skin aging. Under the microscope their collagen bundles are all disorganized!
This may be due to the high amount of Advanced Glycation End Products. AGEs are the result of glucose bonding to other molecules such as proteins. AGEs are destructive to cells. They can cause mutations, block normal functions, and lead to wrinkling and hyperpigmentation. Maintaining normal blood sugar levels, and avoiding diabetes, is a major anti-aging action!
7) Lastly, Dr. Williams turned the audience’s attention to the importance of FAT in looking youthful. The face is fat pads that form an important cushion for the soft tissue envelope. As we age we lose facial fat. This causes hollowing and shadows. In addition, patients with low BMIs who are malnourished lose a lot of fat in their faces. This causes an aged look.