Background: Facial wrinkles, pores, and uneven skin tone are major beauty concerns. There is differential manifestation of aging signs in different ethnic groups. In this regard, studies on Black Africans from the African continent are scarce.Objective: To investigate facial wrinkles, pores, and skin tone in Black African women from Mauritius Island and elucidate the differences to Caucasian women from France.Methods: Facial images were taken using the imaging system ColorFace ® . Wrinkles and pores were measured by their length, depth, surface, volume, and number; for skin tone, we measured L*a*b* and calculated ITA, IWA Newtone , and color homogeneity. Results:We found good correlations of wrinkle and pore scores with expert ranking done on ColorFace ® images for Caucasians (Spearman's rho = 0.78 and 0.72) andBlack Africans (Spearman's rho = 0.86 and 0.65). Caucasians showed more advanced facial signs of aging than Black Africans. Exceptions were vertical lines on upper lip and the depth of pores which were greatest for the Black African subjects. Black Africans had higher heterogeneity scores indicative for uneven skin tone. Luminance (L*) was significantly higher in Caucasians but a* and b* values were significantly higher in the Black African subjects. ITA and IWA Newtone were significantly higher for Caucasians. Conclusions:The high correlation between expert ranking and wrinkle and pore measurements prove ColorFace ® a valid imaging system to study skin aging. Our results show that Africans from the African continent show delayed signs of aging compared to Caucasians. Some exceptions suggest that ethnic differences in facial aging are a complex phenomenon. K E Y W O R D Santi-aging, Black African skin, Caucasian skin, ColorFace®, Ethnic, facial imaging, pores, skin tone, wrinkles

IntroductionWe report on the preparation and efficacy of 10‐hydroxystearic acid (HSA) that improves facial age spots and conspicuous pores.MethodsThe hydration of oleic acid into HSA was catalyzed by the oleate hydratase from Escherichia coli. Following treatment with HSA, collagen type I and type III was assessed in primary human dermal fibroblasts together with collagen type III, p53 protein levels and sunburn cells (SBC) after UVB irradiation (1 J cm−2) by immunohistochemistry on human ex vivo skin. UVB‐induced expression of matrix metalloprotease‐1 (MMP‐1) was determined from full thickness skin by RT‐qPCR. Modification of the fibroblast secretome by HSA was studied by mass‐spectrometry‐based proteomics. In a full‐face, double blind, vehicle‐controlled trial HSA was assessed for its effects on conspicuous facial pore size and degree of pigmentation of age spots in Caucasian women over an 8‐week period.ResultsHSA was obtained in enantiomeric pure, high yield (≥80%). Collagen type I and type III levels were dose‐dependently increased (96% and 244%; P < 0.01) in vitro and collagen type III in ex vivo skin by +57% (P < 0.01) by HSA. HSA also inhibited UVB‐induced MMP‐1 gene expression (83%; P < 0.01) and mitigated SBC induction (−34% vs. vehicle control) and reduced significantly UV‐induced p53 up‐regulation (−46% vs. vehicle control; P < 0.01) in irradiated skin. HSA modified the fibroblast secretome with significant increases in proteins associated with the WNT pathway that could reduce melanogenesis and proteins that could modify dermal fibroblast activity and keratinocyte differentiation to account for the alleviation of conspicuous pores. Docking studies in silico and EC50 determination in reporter gene assays (EC50 5.5 × 10−6 M) identified HSA as a peroxisomal proliferator activated receptor‐α (PPARα) agonist. Clinically, HSA showed a statistically significant decrease of surface and volume of skin pores (P < 0.05) after 8 weeks of application and age spots became significantly less pigmented than the surrounding skin (contrast, P < 0.05) after 4 weeks.ConclusionHSA acts as a PPARα agonist to reduce the signs of age spots and conspicuous pores by significantly modulating the expression of p53, SBC, MMP‐1 and collagen together with major changes in secreted proteins that modify keratinocyte, melanocyte and fibroblast cell behavior.