Bertrand Piot

Effect of the sun on visible clinical signs of aging in Caucasian skin

Objectives Aging signs can be classified into four main categories: wrinkles/texture, lack of firmness of cutaneous tissues (ptosis), vascular disorders, and pigmentation heterogeneities. During a lifetime, skin will change in appearance and structure not only because of chronological and intrinsic processes but also due to several external factors such as gravity, sun and ultraviolet exposure, and high levels of pollution; or lifestyle factors that have important and obvious effects on skin aging, such as diet, tobacco, illness, or stress. The effect of these external factors leads to progressive degradations of tegument that appear with different kinetics. The aim of this study was to clinically quantify the effect of sun exposure on facial aging in terms of the appearance of new specific signs or in terms of increasing the classical signs of aging. Materials and methods This study was carried out on 298 Caucasian women from 30 years to 78 years old. The participants were divided into two groups according to their sun exposure history: 157 women were characterized as sun-seeking, and the other 141 were classified as sun-phobic. This division was made possible by dermatologist grading of heliodermal status on the basis of several observations of classic criteria: wrinkles, sagging, pigmentation heterogeneities, vascular disorders, elastosis, and so on. This work was an opportunity to complete clinical photographic tools by adding in our portfolio new scales for signs observed in the two groups. Thus, 22 clinical parameters were investigated by a panel of twelve trained experts to characterize each woman’s face regarding standardized photographic scales, and thus describe the aging process. Results By calculating statistical correlations between the four clinical clusters (wrinkles/texture, ptosis, vascular disorders, and pigmentation disorders), and real age and apparent age on the one hand and heliodermal status on the other hand, we identified a link between each clinical cluster and aging and the photoaging process. By comparing evaluations of clinical signs between the two groups for each 10-year cluster, we demonstrated that whatever the age, a prevalence of pigmentation disorders for the sun-seeking group (ie, pigmentation) is strongly linked to ultraviolet (UV) exposure. Meanwhile, clinical signs of ptosis are linked more to chronological aging and do not present differences between the two groups, nor, therefore, photoaging. Wrinkles and texture are affected by the two aging processes. Finally, clinical signs of vascular disorders present no evolution with age. Conclusion Clinical signs of aging are essentially influenced by extrinsic factors, especially sun exposure. Indeed UV exposure seems to be responsible for 80% of visible facial aging signs.

Influence of season on some skin properties: winter vs. summer, as experienced by 354 Shanghaiese women of various ages

The facial skin of 354 women, aged 18–80, living in Shanghai, was investigated over two successive 6 month periods, summer and winter. Results from clinical assessments indicate that aging signs, such as wrinkling and sagging, are unaffected over such period.

Clinical study on the effects of a cosmetic product on dermal extracellular matrix components using a high-resolution multiphoton tomograph.

Background/purpose: The aim of this study was to demonstrate the effects of selected plant extracts in a cosmetic cream on the dermal network components after a 3‐month treatment using an in vivo multiphoton tomographic device.

Instrumental and clinical studies of the facial skin tone and pigmentation of Shanghaiese women. Changes induced by age and a cosmetic whitening product.

The pigmentation patterns of facial skin of 354 healthy Chinese women aged 18–80 years were investigated clinically and instrumentally. Chromasphere® was used to acquire pictures from the cheeks of subjects. Facial skin tone was described by L* parameter from the L,a,b system as well as Individual Typology Angle (ITA). Results show that skin tone becomes significantly darker along the life span. Both size of hyper‐pigmented spots and their contrast with surrounding skin were found increased with age. As additional study, 40 women from these 354 subjects were asked to apply daily a whitening cosmetic product for a 2‐month period. Such application led to a significantly lighter skin tone, although this study was not vehicle controlled and we cannot exclude that the increase in L* observed was in some part because of cumulative effects of previously used whitening products, there was an association with lighter skin tone as assessed through both instrumental measurements and self‐perception by most subjects.

Seasonal skin darkening in Chinese women: the Shanghaiese experience of daily sun protection

The facial skin tone of two groups of Chinese women from Shanghai was compared using standard colorimetric space techniques during a 6-month interval between January and July 2011. During the study period, one group of women (n = 40) applied a potent sun-protective cosmetic product daily, while the other group (n = 40) did not use any sun protection. The results, based on images taken using a standardized digital camera coupled to a spectroradiometer, showed that sun protection largely mitigated changes in the components of skin tone, ie, lightness, melanization, and individual typology angle parameters. The skin darkening process appeared to be reduced or prevented in the sun-protected group when compared with the control group. The sun-protected women had participated in an earlier study in 2008, which confirmed that seasonal skin darkening occurs from winter through summer in Shanghaiese women. Comparing the data obtained in the winters of 2008 and 2011, we were able to identify better the impact of 3 years of aging on the components of skin tone. Comparing data between seasons on the same women with (2011 study) and without (2008 study) sun protection highlights the role of the test product in preventing skin darkening.

solar exposure(s) and facial clinical signs of aging in Chinese women: impacts upon age perception

A new reference clinical atlas of facial signs dedicated to photoaging was applied to 301 Chinese women of various ages through standardized photographs. Such approach aimed at better describing the facial changes induced by both real/chronological age and sun exposure and their respective impact on two subcohorts of different behavior with regard to sun exposure. A total of 28 various facial signs were individually graded according to their severity by a panel of experts, and a perceived apparent age of each subject was assessed. Results showed that the severity of major signs significantly increased rather linearly with age, with a higher rate in sun-exposed subjects as compared with subjects who regularly avoid sun exposure. The severity of facial signs, all impacted by sun exposure, better correlated with perceived apparent age than real/chronological age. The protocol used in the present work, similar to that previously applied to two cohorts of French women, assigned a greater impact of sun exposure in the facial aging signs of Asian women – all clinical signs are influenced by extrinsic factors – as compared with Caucasian women of comparable ages, likely related to much more intense ultraviolet (UV) radiation.

Influence of gravity upon some facial signs

Facial clinical signs and their integration are the basis of perception than others could have from ourselves, noticeably the age they imagine we are. Facial modifications in motion and their objective measurements before and after application of skin regimen are essential to go further in evaluation capacities to describe efficacy in facial dynamics. Quantification of facial modifications vis à vis gravity will allow us to answer about ‘control’ of facial shape in daily activities.

In vivo multiphoton tomography: a non invasive powerful tool for biochemical investigation of human skin

In vivo simultaneous collagen and elastin measurements using the multiphoton tomograph DermaInspect have been performed in skin dermis. We showed it was possible to get simultaneous measurements of autofluorescence (AF) and Second Harmonic Generation (SHG) with a newly developed device using 2 PMTs for time-correlated single photon counting. Unlike elastin (AF), collagen structures are able to generate second harmonics (SHG). Comparing the images and SHG / AF ratios recorded in the depth of the outer and inner sides of the forearm of two European female volunteers (31 and 60 years old, respectively) shows differences in collagen and elastin fibres density. It decreases with depth in the 60 years old volunteer compared to the younger one, and the skin of younger volunteer shows more collagen.

Impact of pigmentary disorders on quality of life in Japan: Interest of the BeautyQoL instrument

Skin pigmentary disorders and uneven skin tone represent common cosmetic concerns in Japan where fairer skin is culturally desirable. As the demographics of Asian countries continue to evolve, there is a need to understand the impact of cosmetic skin concerns on quality of life (QoL). 199 Japanese women self-claiming facial skin pigmentation disorders were asked to complete the BeautyQoL questionnaire, and the results were compared with those of a control group of 200 women. Of the five dimensions of the BeautyQoL questionnaire, the dimension “mood” appeared to be significantly lower in the group presenting facial dark spots, as compared with the control group (p < 0.05). In the group presenting facial dark spots, the five dimensions and the global score showed that subjects concerned had lower scores than subjects less concerned, even if statistical significance was not reached. This study confirms that common pigmentary disorders such as facial black spots may negatively impact QoL. Further comparative studies with a controlled randomized design would be necessary to confirm these findings.