Aging of Integumentary system

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1 Aging of Integumentary system SCBM 304 Biological Sciences of Aging Lect. Somphong Narkpinit, M.D. Department of Pathobiology Faculty of Science Mahidol University somphong.nar@mahidol.ac.th

2 Aging of skin

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4 1. Intrinsic Skin Aging

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6 Mechanism OH -, O 2 - lipid peroxidation H 2 O 2 Cell death: keratinocytes

7 Epidemis (หน งกำพร ำ) Most striking and histologic change Histo- flattening of DEJ (smaller surface between epidermis and dermis) Old skin separate epidermis & dermis tear and superficial abrasion after minor trauma

8 Age (30-80Y) associate thining~ % Evidence suggested epidermal keratinocyte senesce and senescent cells are more resist to apoptosis accumulate mutation and risk for malignant transformation

9 Age effects 1. Percutaneous absorbtion depend on drug structure : Hydrophillic eg. Hydrocortisone, Benzoic acid less well absorb : Hydrophobic eg. Testosterone & estradiol well absorb 2. Delay recovery barrier function - Slow replace neutral lipid amount lipid in lamella bodies Elderly : Skin appears dry and flaky esp. lower extremities ( filaggrin)

10 Elderly Epidermis 1. Decrease epidermal turnover rate 2. Decrease linear growth rate of hair & nail 3. Decrease epidermal repair rate after wounding

11 Elderly Epidermis 4. number of enzyme active melanocytes per unit surface area 5. protective barrier to UV 6. number of Melanocyte nevi 7. number of Langerhans cells (skin immune effector cells) ~ 20-50% 6. Vit D production Osteoporosis implicated in DM,HT and prevalent tumor

12 Dermis (หน งแท ) Loss of dermal thickness ~ 20% Inflam response ( synthesis & secretion cytokine and inflammatory mediator) of keratinocyte Vascular wall thickening (esp. Lower legs) vascular fragility Vascular bed esp. vertical capillary loop pallor ( 60% blood flow cut.&basal) & temperature

13 Vascular at hair bulb, eccrine, apocrine and sebaceous glands Density & Lumen size of lymphatic vessels rigidity & lymphatic drainage Collagen (1% per year in adult) Collagen I and II synthesis Enzyme process of collagen & non enzyme glycosylation impair wound healing Number and diameter of elastic fiber fragment, small cyst, lacunae at DEJ

14 Elastic fiber component (elastin, fibrillin, fibukin2) Fibulin-5 (scaffold for elastic fiber) * marker of skin aging Ground substance (Mucopolysaccaride, GAGs, Proteoglycans)

15 Subcutaneous Muscle and bone - Striated muscle & Facial muscle accumulate age pigment ( Lipofusinmarker cellular damage) - Neuromuscular control wrinkle - Subcutaneous fat : forehead, periorbital, buccal and temporal - Subcutaneous fat : submental, nasolabial fold and lateral malar areas - facial bone mass

16 Hair End of fifth decade ~ ½ of population has at least 50% gray scalp hair Loss melanocyte rapid in hair > skin Hair graying reflect loss melanocyte stem cell in hair follicle bulge Scalp hair gray more rapidly than body hair Balding results from androgen-dependent conversion

17 Cutaneous glands and Nerves Eccrine 15% and output/gland Spontaneous sweating is reduced ~ 70% Decrease apocrine gland size and function Sebaceous gland size & number not change sebum production and production gonadal or adrenal androgen Pacinicn & Meissner s corpuscles sensation perception

18 2. Photoaging

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21 Photo aging - Prominent feature is elastosis yellow discoloration and pebbly surface Habitually sun-exposed skin above collar line is prominently wrinkled and lax

22 Photo aging - Histological - Tangle mass of degrade elastic tissue amorphous mass - ground substance - collagen MMP

23 Photo aging - Histology -- inflam cells giving term Heliodermatitis (cutaneous inflammation) - Immunohisto -- CD4 in dermis

24 Photo aging Dermal vasculature Mildly venule wall thickening Severe thin vessel wall telangiectasis Photoaging occur skin phototypes I & II and darker skin phototypes III & IV with Hx of ample past sun exposure

25 Photo aging Skin type I & II Atrophic and Dysplastic change with actinic keratoses and epidermal malignancies Skin type III & IV lentigenes, and coarseness Hypertrophic, furrowing,

26 Type I Atrophic skin Few wrinkles with several actinic keratoses Type IV Hypertrophic skin with deep wrinkles and leather-like coarse skin

27 Photo aging * Major clinical features in Asian skin Solar lentigines, mottled pigmentation, Melasma, moderate to severe wrinkling

28 Action Spectrum UVB - Major cause of DNA damage - Induce inflam and immunosuppression - Induce Ornithine decarboxylase (biosyn. Of polyamine) Stimulate cellular proliferation Elastin degradation

29 Action Spectrum UVA - Larger role in photoaging - Greater depth penetration into dermis - Induce synthesis & release cytokine & MMP - Etiology factor generate of BBC * UVA more effective than UVB inducing oxidative damage

30 Sunlight Transmit infrared irradiation (IR) 760nm-1mm Wavelenght 760-1,400nm penetrate to subcut. with skin temp. Wavelenght 1,400 nm-1mm absorb epithelial & increase temp temperature

31 Smoking and Skin Aging Exacerbate photoaging with direct correlation between number of pack-years and severity of wrinkling and grayish discoloration Histo-elastic fiber thickening and fragmentation similar sun damaged skin Poor wound healing capacity and skin CA

32 Smoking and Skin Aging Dermal elastosis result from elastase activity in neutrophil Chronic dermal ischemia Preoxidant effect Stratum corneum water content and accelerate hydroxylation of estradiol Estrogen contributed to dryness and atrophy

33 Relevance to skin disease Disorder associated instrinsic loss of cutaneous cellular function More common systemic disease such as DM, Vascular insufficiency, and various neurologic syndrome tolerance systemic drug due to metabolism, and renal excretion lean body mass,

34 Skin cancer Including melanoma due to cumulative exposure to carcinogen and risk to mutation Cause is UV irradiation Habitual sunexposure of fair skin induce SCC e.g. Actinic keratosis Risk to BCC and Malignant melanoma relate to total sun exposure and intence intermittent sun exposure

35 Analysis of face Contour : Ideal proportion, symmetrical, Volume Texture : Smoothness, colour, Brightness, flawless

36 Ideal proportion : shape of face

37 Ideal proportion

38 Ideal proportion Facial Analyses The width of nose at its base should be approximately the distance between the eyes (medial canthus). The length of upper lip is about twice that of lower lip and chin. Tip - Slight Upward Rotation : better Nasofacial angle = 36 degrees Nasofrontal angle = 120 degrees Nasomental angle = 130 degrees Mentocervical angle = 85 degrees

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40 Age related contour changes Subcutaneous fat loss Facial musculature change Change in catilage and bone Malar cresent Cheek depression Nasolabial formation Prejowl sulcus Jowl formation Platysmal band(turkey neck)

41 Age related contour changes

42 Analysis of contour in aging face

43 Age related textural changes Superficial and deep rhytides Pigmentary disturbances Telangiectasis formation Loss of skin elasticity Actinic keratosis Sebaceous gland hyperplasia and skin tumor

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45 Common problems of skin texture Wrinkles Hyperpigmentation & PIH Dilated pore Acne scar Oily face

46 Dynamic wrinkles Botulinum toxin A,B contraction of muscles that are attached to the overlying skin Static wrinkles Botulinum toxin, Dermal filler, fractional ablative laser, RF, fractional RF, Thread Lifting & Rejuvenation lack of elasticity of the skin caused from sun damage, smoking, genetics, poornutrition, or from prolonged dynamic wrinkling Wrinkle folds Dermal filler, Monopolar RF(Thermage),ultrasound (Ulthera), Thread Lifting sagging of the underlying facial structures

47 Hyperpigmentation Superficial pigmentation : solar lentigine, epidermal melasma, superficial freckles Deep pigmentation : Dermal melasma, PIH, nevus of hori, ota, TX --- > topical whitening, microdermabrasion, peeling, TCA ablative laser(fractional co2 and urbium yag) non-ablative laser(q-switch ND yag laser; Medlite C-6, Helios)

48 Dilated pore Hair follicle Obstruction collagen loss excess of sebum secretion, a slackening of the pore wall and an abnormal keratinisation process Remove hair (gentle yaq) Keratolytic agent (AHA, retinoid) Collagen Stimulation (Long pulse ND-yaq, ablative laser),ipl

49 Acne scar TCA Subcision Fractional co2 Fractional urbium Fractional RF Microneedle RF Fractional co2 Fractional urbium Fractional RF Microneedle RF

50 Oily skin Remove over production of oil : paper sheath, washing with water as usual, toner Food??? Topical medication : Lotion P,siriraj powder, resorcinol Oral medication : isotretinoin Laser treatment NEW : BOTOX treatment

51 Thank you for your attention