How is Asian/Chinese Skin different for photodamage?How is Asian/Chinese Skin different for photodamage?

Overview of Ultraviolet Effects:Acute DamageChronic Damage

UV Pathways to Skin DamageUV Pathways to Skin DamageDamaging effects are effects are 80% UVB/20% UVA80% UVB/20% UVA

Direct DNA damage

UVB

ROS generation

UVA

Inflammatory Mediators

Inflammatory Mediators

Inflammatory Mediators

Inflammatory Mediators

UV Pathways to Skin DamageUV Pathways to Skin DamageDamaging effects are effects are 80% UVB/20% UVA80% UVB/20% UVA

Enzymes

Matrix-degradingenzymes (MMP, etc)

Matrix-degradingenzymes (MMP, etc)

Enzymes

UV Pathways to Skin DamageUV Pathways to Skin DamageDamaging effects are effects are 80% UVB/20% UVA80% UVB/20% UVA

Enzymes

Matrix-degradingenzymes (MMP, etc)

Matrix-degradingenzymes (MMP, etc)

Enzymes

UV Pathways to Skin DamageUV Pathways to Skin DamageDamaging effects are effects are 80% UVB/20% UVA80% UVB/20% UVA

Matrix-degradingenzymes (MMP,

etc)

Enzymes

UV Pathways to Skin DamageUV Pathways to Skin DamageDamaging effects are effects are 80% UVB/20% UVA80% UVB/20% UVA

• Direct DNA damage– Immune suppression

– Mutations and skin cancer

• Reactive Oxygen Species

UVB UVA

Inflammation

PigmentationMetalloproteineasesCollagen and elastin degradationSagging, wrinkles

Both UVA and UVB both Both UVA and UVB both lead to chronic photodamagelead to chronic photodamage

Chinese women 14 – 20 years old

Chinese women 14 – 20 years old

Indian women 14 – 20 years old

Chinese women 65 - 75 years old

Indian women 65 - 75 years old

• Skin aging parameters start later than Caucasian1,2 with different patterns

• Within Chinese population, skin aging parameters start earlier for higher UV exposure by approximately 10 years1

• Korean wrinkle formation is highly correlated with sun exposure3

• Pigment changes are different in Asian skin versus Caucasian with aging and photoaging1

• Photoaging differences are not all explained by differences in pigmentation

1. Zhao, P. Wang C. Solar ultraviolet Radiation and Skin Damage: An epidemiological study among a Chinese popoulation. Archives of Environmental Health, 53:6, 1998.

2. Chung, J.H. Photoaging in Asians. Photodermatology, Photoimmunology & Photomedicine. 19:109-121. 20033. Chung, J.H. Et al. Cutaneous Photodamage in Koreans. Archives of Dermatology 137:1043-1051.

How is Asian/Chinese Skin How is Asian/Chinese Skin different for photodamage?different for photodamage?

Photograph courtesy of Robert & Margaret Weiss, MD

Photodamage is not just about Photodamage is not just about pigmentation and wrinklespigmentation and wrinkles

Photograph courtesy of Robert & Margaret Weiss, MD

• UV exposure induces photodamage and photoaging through several mechanisms

• UVA can produce photoaging in the absence of UVB

• In order to reduce photodamage, sunscreens must protect against both UVB and UVA

Effects of UV on Photoaging:Effects of UV on Photoaging:ConclusionsConclusions