1. A Presentation By Group 2 : Zara Hammonds Linda Jones Erika Kline Katherine Konnert

2. Key Terms 1. Aging: process of progressive decrease in functioning and reserve capacity of all organs, including the skin Intrinsic Aging- aging that is naturally occurring and chronological Extrinsic Aging- aging that is compounded and accelerated by environmental factors (ex. exposure to UV radiation and smoking) 2.Free Radicals: compounds formed when an oxygen molecule combines with other molecules, yielding an odd number of electrons Reactive Oxygen Species (ROS)- oxygen-centered molecules Reactive Nitrogen Species (RNS)- nitrogen-centered molecules 3.Antioxidants: molecules capable of inhibiting oxidation of other molecules Exogenous Antioxidants- obtained from our diet Endogenous Antioxidants- made by our body 4.Oxidative Stress: phenomenon in which the balance between free radicals and antioxidants is lost

3. Theory of Aging and Free Radicals In the 1950’s, Denham Harman theorized that the generation of free radicals leads to cellular damage when free radicals take electrons from DNA and other biomolecules. This cellular damage can cause aging and diseases of numerous systems of the body, including the integumentary system. Sources of free radicals can be exogenous (ex. Smoking and pathogenic microorganisms) or endogenous (ex. Inflammatory cells).

4. Skin and Free Radicals Even healthy skin has free radicals, which are neutralized by antioxidants. This neutralization process prevents cell damage by maintaining homeostasis. Oxidative Stress results when that homeostasis is lost. Chronic oxidative stress may be a cause of many disorders of the integumentary system, as well as other systems of the body. Some of these dermatological disorders are aging of the skin and deep wrinkles, melanomas, psoriasis, atopic dermatitis, and acne vulgaris.

5. Antioxidants and Their Distribution in Skin Antioxidants that inhibit oxidation of free radicals and prevent oxidative stress are classified as endogenous and exogenous. The skin naturally contains many endogenous antioxidants because it is exposed to numerous environmental free radicals. The epidermis and dermis contain large amounts of ascorbic acid, uric acid and glutathione. The viable layer of the epidermis contains vitamin E, catalase, superoxide dismutases, and glutathione. The cornified envelope (the outermost layer of the skin) contains glutathione, vitamin C, uric acid, and coenzyme Q10, with the highest concentration in the deepest layers.

6. Antioxidant Activity and Conclusion Exogenous Antioxidants are mostly obtained from our diet, but research is being conducted on combining antioxidants with creams (ex. sunscreen). Pomegranate juice has the highest antioxidant activity out of all of the beverages In conclusion, free radicals and oxidative stress damage DNA, membrane, and collagen structures, possibly contributing to aging and other dermatological disorders. Research suggests that exogenous (oral and topical) antioxidants may provide benefits from the damage, but long term studies are needed to validate these findings. that were studied for their potency.

7. Work Cited Kikkeri, N. N., Pai, V. V., & Shukla, P. (2014, April-June). Antioxidants in dermatology. Indian Dermatology Online Journal, 5(2), 210-214. Retrieved from http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4030358/