Relationship between skin response to ultraviolet exposure and skin color type

Abstract

Sun exposure is responsible for detrimental damage ranging from sunburn to photoaging and skin cancer. This damage is likely to be influenced by constitutive pigmentation. The relationship between ultraviolet (UV) sensitivity and skin color type was analyzed on 42 ex vivo skin samples objectively classified from light to dark skin, based on their values of individual typology angle (ITA) determined by colorimetric parameters. The biologically efficient dose (BED) was determined for each sample by quantifying sunburn cells after exposure to increasing doses of UV solar-simulated radiation. Typical UV-induced biologic markers, other than erythema, such as DNA damage, apoptosis and p53 accumulation, were analyzed. A statistically significant correlation was found between ITA and BED and, ITA and DNA damage. Interestingly, DNA lesions were distributed throughout the whole epidermal layers and the uppermost dermal cells in light, intermediate and tanned skin while they were restricted to suprabasal epidermal layers in brown or dark skin. Our data support, at the cellular level, the relationship between UV sensitivity and skin color type. They emphasize the impact of DNA damage accumulation in basal layer in relation to the prevalence of skin cancer.

Risk Factors for Vitamin D Deficiency and Relationship with Cardiac Biomarkers, Inflammation and Immune Restoration in HIV-Infected Youth

“…No published study investigating vitamin D status in HIV has evaluated skin pigmentation in lieu of race. It has long been known that blacks have a higher prevalence of vitamin D deficiency due to increased skin pigmentation which decreases the production of vitamin D 3 in the skin [51]. However, this study suggests that skin pigmentation may be a better method of identifying people who are the most at risk.…”

Risk Factors for Malignant Melanoma in White and Non-White/Non–African American Populations: The Multiethnic Cohort

“…Supporting this suggestion, experimental studies have shown that the amount of UVR-related DNA damage did not differ among those with darker skin phototype compared to whites (33). The difference in disease incidence may be partially explained from the observations that among non-whites, the UVR-related DNA damage may have a higher rate of repair (33) and/or may be restricted to the upper layers of skin (34). …”

Alternate Light Source Findings of Common Topical Products

“…It was calculated based on luminosity (L*) and blue-yellow (b*) colorimetry measurements of the skin (Del Bino, Sok, Bessac, & Bernerd, 2006). Participants were categorized into one of six skin color categories previously established by the cosmetic and dermatology industries (very light, light, intermediate, tan, brown, and dark) (COLIPA, 2007;Del Bino et al, 2006). This objective method of categorizing skin color based on ITA has been effectively used in previous bruise research (Scafide, Sheridan, Campbell, Deleon, & Hayat, 2013) and within the dermatologic and cosmetic industries (Uhoda, Pierard-Franchimont, Petit, & Pierard, 2003).…”

“…Using a handheld Konica Minolta ® CM-700d spectrophotometer, skin color was assessed using the Individual Typology Angle (ITA). It was calculated based on luminosity (L*) and blue-yellow (b*) colorimetry measurements of the skin (Del Bino, Sok, Bessac, & Bernerd, 2006). Participants were categorized into one of six skin color categories previously established by the cosmetic and dermatology industries (very light, light, intermediate, tan, brown, and dark) (COLIPA, 2007;Del Bino et al, 2006).…”