Cosmetics Break the Skin Barrier n The New
Cosmetics Break the Skin Barrier n The New York Times n January 8, 2005, Saturday n By CLAUDIA H. DEUTSCH
Enhancing Methods for TDD Chemical enhancement Permeation enhancers: eg, terpene Prodrugs n Physical enhancement Electrical methods Iontophoresis; Electroporation Mechanical methods Sonophoresis, Microneedles, Laser n
Skin aging is divided into 2 major effects categories: n Intrinsic aging (內在老化) n extrinsic aging (外在老化)
Factors n Ultraviolet radiation (UVR) n Chemicals n Smoking As UVR is the most significant of these factors, extrinsic aging has been termed photoaging.
Six Signs of Aging n Fine lines and wrinkles (紋) n Blotches and age spots (斑) n Poor skin texture (少) n Poor skin tone (鬆) n Increased dryness (乾) n Visible pores (孔)
Antiaging Cosmetics Dr. Hung
Sunscreens Dr. Hung
自由基清除 n n n Vitamin C -Tocopherol, Tocopheryl acetate Ubiquinones (Q 10), Idebenone -lipoic acid Green tea extract Genistein -carotene melatonin Phenolic acid SPD(海藻提煉物;Superphyco dismutase) Melanin
Co. Q (Q 10) n Ubiquinone, Co. Q 10 (ubiquinol in the reduced form) is a vitaminn n n based ingredient that possesses complex antioxidant properties. 10 -fold higher levels in the epidermis than the dermis Co. Q in ethanol results in penertration into the stratun corneum (20%), and 2% into the dermis. (Biofactor 1999, 9, 371) The expression of collagenase m. RNA induced by UVA can be significantly reduced by pretreatment with Q 10 (11 m. M Q 10 is as effective as 3 m. M vitamin E. It acts in synergy with vitamin E to protect cell membranes against oxidative stress. Idebenone, a synthetic variant of Co. Q 10 was appears to share similar benefits as Co. Q 10.
Retinoids臨床上對皮膚的好處: (1)用來治痘痘 (2)使角化不正常的地方恢復正常 (2)可以刺激或抑制keratinocyte activity,有modifier的作 用 (4)anti-inflammatory action、modifying glycoprotein synthesis作用到真皮層,使老化的皮膚變年輕 (5)decrease collagenase activity,可避免collagen被破 壞,讓皮膚彈性變好
Retinoids in cosmetics n vitamin A alcohol (retinol) n vitamin A esters (retinyl palmitate, retinyl acetate) n vitamin A aldehyde (retinal) n tretinoin (retinoic acid)
Vitamin B 3 (Niacin) 菸鹼酸 抑制黑色素體從黑色素細胞轉移 n Niacinamide or nicotinamide n Increases the production by keratinocytes of ceramides n Improve barrier function and decrease transepidermal water loss n Clinical: rosacea, acne and psoriasis n Suppression of melanosome transfer (BJD 2002; 147: 20 -31)
促進黑色素從角質層剝離 n Azelaic acid n AHA, BHA n Urea
Skin damage side effects from skin lightening treatments Skin whitening agent Skin surface Malanin layer Lower skin surface Increased MMP activity
Moisturizers n Moisturizers are defined as chemicals that increase the water content of the stratum corneum and are hydrating agents. n Moisturizers work by using ingredients that are occlusive (阻水劑) and/or humectant (濕 潤劑) agents. n These ingredients are the same or similar to natural components in the skin (biomimetic).
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