Evaluation of a daily facial massage on perceived sleep quality and well-being: A pilot study.

OBJECTIVE: Sleep disorders are widespread and constitute a major public health risk. The present study thus aims to investigate the effect of a facial cosmetic self-massage daily routine on women's sleep and well-being. METHODS: The present pilot study was conducted on 62 middle-aged women declaring daily tiredness and sleep troubles. We examined the effect of a regular facial cosmetic self-massage routine on sleep patterns, daytime sleepiness, and well-being over the course of 2 months. RESULTS: After 1 and 2 months, our results show improved sleep quality (Pittsburgh Sleep Quality Index, PSQI - -20.2% after 2 months), reduced daytime sleepiness (Epworth Sleepiness Scale, ESS, -31.2% after 2 months), and increased well-being measures. The number of participants with abnormal sleep (PSQI >5) decreased over the course of the experiment as well, from 71.9% to 49.2% at the end of the 2 months [odds ratio 95% CI for decrease: 0.38 (0.18-0.81)]. Similarly, the number of participants with excessive daytime sleepiness (>10 on the ESS) decreased over the course of the study from 44.3% to 21% after 1 month [95% CI: 0.33 (0.15-0.73)] and to 16.1% after 2 months [95% CI: 0.24 (0.10-0.56)]. CONCLUSIONS: These results suggest that a facial cosmetic self-massage routine may improve sleep patterns and is likely to be a useful addition to a standard sleep hygiene routine.

OBJECTIF: Les troubles du sommeil sont répandus et constituent un risque majeur pour la santé publique. La présente étude vise donc à examiner l'effet d'une routine quotidienne d'auto­massage cosmétique du visage sur le sommeil et le bien­être des femmes. MÉTHODES: La présente étude pilote a été menée auprès de 62 femmes d'âge moyen déclarant une fatigue quotidienne et des troubles du sommeil. Nous avons examiné l'effet d'une routine régulière d'auto­massage cosmétique du visage sur les habitudes de sommeil, la somnolence diurne et le bien­être sur une période de deux mois. RÉSULTATS: Après un et deux mois, nos résultats montrent une amélioration de la qualité du sommeil (échelle de qualité du sommeil de Pittsburgh [Pittsburgh Sleep Quality Index, PSQI]: −20.2% après deux mois), une diminution de la somnolence diurne (échelle de somnolence d'Epworth [Epworth Sleepiness Scale, ESS]: −31.2% après deux mois) et une augmentation des valeurs dans les mesures du bien­être. Le nombre de participantes présentant un sommeil anormal (PSQI > 5) a également diminué au cours de l'expérience, passant de 71.9% à 49.2% à la fin des deux mois [rapport de cotes avec IC à 95% pour la diminution: 0.38 (0.18­0.81)]. De même, le nombre de participantes présentant une somnolence diurne excessive (>10 sur l'échelle ESS) a diminué au cours de l'étude passant de 44.3% à 21% après un mois [IC à 95%: 0.33 (0.15­0.73)] et à 16.1% après 2 mois [IC à 95%: 0.24 (0.10­0.56)]. CONCLUSIONS: Ces résultats indiquent qu'incorporer une routine d'auto­massage cosmétique du visage peut favoriser de meilleures habitudes de sommeil, et qu'elle pourrait être bénéfique en complément d'une routine d'hygiène du sommeil habituelle.

Skin microbiome attributes associate with biophysical skin ageing.

Two major arms of skin ageing are changes in the skin's biophysical conditions and alterations in the skin microbiome. This work partitioned both arms to study their interaction in detail. Leveraging the resolution provided by shotgun metagenomics, we explored how skin microbial species, strains and gene content interact with the biophysical traits of the skin during ageing. With a dataset well-controlled for confounding factors, we found that skin biophysical traits, especially the collagen diffusion coefficient, are associated with the composition and the functional potential of the skin microbiome, including the abundance of bacterial strains found in nosocomial infections and the abundance of antibiotic resistance genes. Our findings reveal important associations between skin biophysical features and ageing-related changes in the skin microbiome and generate testable hypotheses for the mechanisms of such associations.

A genome wide association study identifies new genes potentially associated with eyelid sagging.

Sagging eyelid is considered as an outward of skin ageing and may cause medical issues. However, little is known about the factors involved in sagging eyelid. The study, which aims at determining genetic risk factors for eyelid sagging, was conducted in a cohort of 502 unrelated Caucasian women living in the Paris region. All included participants were aged between 44 and 70 years old (mean age, 57.6 years old). The severity of sagging eyelid was graded in 6 categories by a dermatologist using standardized photographs of the face. A genome wide association study adjusted on potential risk factors (including age and smoking habits) was conducted to identify genetic associations. Two single nucleotide polymorphisms in total linkage disequilibrium on chromosome 10, rs16927253 (P = 7.07 × 10-10 ) and rs4746957 (P = 1.06 × 10-8 ), were significantly associated with eyelid sagging severity. The rs16927253-T and rs4746957-A alleles showed a dominant protective effect towards eyelid sagging. These polymorphisms are located in intronic parts of the H2AFY2 gene which encodes a member of the H2A histone family and very close to the AIFM2 gene that induces apoptosis. Additionally, single nucleotide polymorphisms with a false discovery rate below 0.25 were located nearby the type XIII collagen COL13A1 gene on chromosome 10 and in the ADAMTS18 gene on chromosome 16. Several relevant genes were identified by the genome wide association study for their potential role in the sagging eyelid severity.

Cosmetics increase skin evenness: Evidence from perceptual and physical measures.

BACKGROUND: Cosmetics are commonly attributed with increasing skin evenness, yet little published data characterizes the effect, either perceptually or physically. We therefore investigated whether makeup increases skin evenness using a perceptual measurement and two physical measurements of color and luminance homogeneity. MATERIALS AND METHODS: Twenty-two French women (aged 29-45 years) were photographed without cosmetics, with self-applied cosmetics, and with professionally-applied cosmetics. In Study 1, 143 participants rated skin evenness. In Study 2, each face was delineated to create regions of interest (ROI) in the cheek and forehead areas. Both ROIs were then analyzed for luminance homogeneity using an established measure (Haralick homogeneity) and a new measure that incorporates chromaticity (H76 ). RESULTS: In Study 1, the faces were rated as having more even-looking skin with either self-applied cosmetics or professionally-applied cosmetics than without cosmetics. In Study 2, the luminance homogeneity measure found that the cheek ROI, but not the forehead ROI, was more homogeneous after both self-applied cosmetics and professionally-applied cosmetics when compared to without cosmetics. The new measure incorporating chromaticity found greater homogeneity in both ROIs in the two cosmetics conditions. The new measure incorporating chromaticity also better predicted the perceived skin evenness ratings from Study 1. CONCLUSION: These results provide systematic empirical evidence that makeup increases perceived skin evenness, and that these increases are partly predicted by physical measurements of skin luminance and color. The data also indicate that H76 -the new measure of skin evenness that incorporates chromaticity-better predicts perceived skin evenness.

Validation of digital photographic reference scales for evaluating facial aging signs.

BACKGROUND: Validated tools are essential to evaluate facial skin aging for both dermatological and cosmetic investigations. While many visual aging scales have been developed, few have been validated and none in terms of degree of distinguishability (DD). We developed and validated a series of visual scales using a novel digital interface for scoring facial skin aging in Caucasian women. MATERIALS AND METHODS: Three dermatologists independently established scales for 12 distinct aging signs from high-definition facial photographs of 400 adult women (Fitzpatrick phototypes I-IV) taken under standardized conditions. They then selected a consensus scale for each individual sign with a representative photo per grade. Scales were integrated into a digital interface allowing simultaneous viewing of all grades of each scale alongside the photograph of a test subject. Next, scales were validated by a different dermatologist, a general practitioner and a non-medical expert skin evaluator using photos of 350 women which had not been used for establishing the scales. RESULTS: Kappa estimates showed almost perfect agreement for wrinkle and skin aging scales (≥0.85) and moderate to substantial agreement for scales relating to color irregularities (telangiectasia, solar lentigines, freckles) for both inter- and intra-observer reproducibility. Intra-observer DD estimates were mostly high. Non-dermatologists performed well on reproducibility for both Kappa (from 0.6 to 0.9) and DD estimates. CONCLUSION: Our work demonstrates that the digital interface scales for 12 distinct aging features are highly suitable for use in clinical and epidemiological studies on skin aging by both dermatologists and non-dermatologists.

Identification of New Biological Pathways Involved in Skin Aging From the Analysis of French Women Genome-Wide Data.

Skin aging is an ineluctable process leading to the progressive loss of tissue integrity and is characterized by various outcomes such as wrinkling and sagging. Researchers have identified impacting environmental factors (sun exposure, smoking, etc.) and several molecular mechanisms leading to skin aging. We have previously performed genome-wide association studies (GWAS) in 502 very-well characterized French women, looking for associations with four major outcomes of skin aging, namely, photoaging, solar lentigines, wrinkling, and sagging, and this has led to new insights into the molecular mechanisms of skin aging. Since individual SNP associations in GWAS explain only a small fraction of the genetic impact in complex polygenic phenotypes, we have made the integration of these genotypes into the reference Kegg biological pathways and looked for associations by the gene set enrichment analysis (GSEA) approach. 106 pathways were tested for association with the four outcomes of skin aging. This biological pathway analysis revealed new relevant pathways and genes, some likely specific of skin aging such as the WNT7B and PRKCA genes in the "melanogenesis" pathway and some likely involved in global aging such as the DDB1 gene in the "nucleotide excision repair" pathway, not picked up in the previously published GWAS. Overall, our results suggest that the four outcomes of skin aging possess specific molecular mechanisms such as the "proteasome" and "mTOR signaling pathway" but may also share common molecular mechanisms such as "nucleotide excision repair."

Psoriasis: characterization of six different clinical phenotypes.

Until recently, psoriasis was considered as a single disease entity. However, the discovery of major differences between early- or late-onset psoriasis suggests the presence of distinct disease phenotypes which may differ in their pathophysiology and in their treatment responsiveness. The objective of this study was to use exploratory data analysis methods to identify potential clinical psoriasis phenotypes without a priori hypotheses. A prospective questionnaire-based survey collected comprehensive informations on the main clinical characteristics of 1484 psoriatic patients. Six statistically different clusters of clinical symptoms were observed, corresponding at least to six different clinical psoriasis phenotypes. Moreover, discriminant functions allow patients to be assigned to one or other of these phenotypes. Our findings open the way to focus genetic, pharmaco-genetic, pathophysiological and therapeutic studies on more homogenous group of patients.

Variations of skin biophysical properties after recreational swimming.

BACKGROUND/PURPOSE: Sensations of itching and skin tightness are frequently reported after recreational swimming in pool water. Our objective was to measure the potential changes occurring at the skin surface under such conditions. METHODS: Nine women participated in this study, which consisted of two periods. During a 4-day control period, basal biophysical skin parameters were assessed every morning. On the first day, measurements were also performed in the afternoon. The second study period followed the same study design as for the control period, except that, on the first day, women swam for 1 h in a public pool, between the measurements performed in the morning and the afternoon. Skin capacitance, transepidermal water loss, skin temperature, skin pH and sebum casual level (SCL) were measured on facial and body sites. RESULTS: During the control period, biophysical skin parameters did not show significant variations. By contrast, h after swimming, biophysical values showed significant changes for all test sites: skin pH increased, whereas skin capacitance and SCL decreased. Biophysical parameters returned to baseline values the day after swimming. CONCLUSION: Our results demonstrate that recreational swimming leads to significant transient changes in skin surface properties of women with healthy skin.

A novel role for NUPR1 in the keratinocyte stress response to UV oxidized phospholipids.

Ultraviolet light is the dominant environmental oxidative skin stressor and a major skin aging factor. We studied which oxidized phospholipid (OxPL) mediators would be generated in primary human keratinocytes (KC) upon exposure to ultraviolet A light (UVA) and investigated the contribution of OxPL to UVA responses. Mass spectrometric analysis immediately or 24 h post UV stress revealed significant changes in abundance of 173 and 84 lipid species, respectively. We identified known and novel lipid species including known bioactive and also potentially reactive carbonyl containing species. We found indication for selective metabolism and degradation of selected reactive lipids. Exposure to both UVA and to in vitro UVA - oxidized phospholipids activated, on transcriptome and proteome level, NRF2/antioxidant response signaling, lipid metabolizing enzyme expression and unfolded protein response (UPR) signaling. We identified NUPR1 as an upstream regulator of UVA/OxPL transcriptional stress responses and found this protein to be expressed in the epidermis. Silencing of NUPR1 resulted in augmented expression of antioxidant and lipid detoxification genes and disturbed the cell cycle, making it a potential key factor in skin reactive oxygen species (ROS) responses intimately involved in aging and pathology.

Small extracellular vesicles and their miRNA cargo are anti-apoptotic members of the senescence-associated secretory phenotype.

Loss of functionality during aging of cells and organisms is caused and accompanied by altered cell-to-cell communication and signalling. One factor thereby is the chronic accumulation of senescent cells and the concomitant senescence-associated secretory phenotype (SASP) that contributes to microenvironment remodelling and a pro-inflammatory status. While protein based SASP factors have been well characterized, little is known about small extracellular vesicles (sEVs) and their miRNA cargo. Therefore, we analysed secretion of sEVs from senescent human dermal fibroblasts and catalogued the therein contained miRNAs. We observed a four-fold increase of sEVs, with a concomitant increase of >80% of all cargo miRNAs. The most abundantly secreted miRNAs were predicted to collectively target mRNAs of pro-apoptotic proteins, and indeed, senescent cell derived sEVs exerted anti-apoptotic activity. In addition, we identified senescence-specific differences in miRNA composition of sEVs, with an increase of miR-23a-5p and miR-137 and a decrease of miR-625-3p, miR-766-3p, miR-199b-5p, miR-381-3p, miR-17-3p. By correlating intracellular and sEV-miRNAs, we identified miRNAs selectively retained in senescent cells (miR-21-3p and miR-17-3p) or packaged specifically into senescent cell derived sEVs (miR-15b-5p and miR-30a-3p). Therefore, we suggest sEVs and their miRNA cargo to be novel, members of the SASP that are selectively secreted or retained in cellular senescence.

A genome-wide association study in Caucasian women suggests the involvement of HLA genes in the severity of facial solar lentigines.

Solar lentigines are a common feature of sun-induced skin ageing. Little is known, however, about the genetic factors contributing to their development. In this genome-wide association study, we aimed to identify genetic loci associated with solar lentigines on the face in 502 middle-aged French women. Nine SNPs, gathered in two independent blocks on chromosome 6, exhibited a false discovery rate below 25% when looking for associations with the facial lentigine score. The first block, in the 6p22 region, corresponded to intergenic SNPs and also exhibited a significant association with forehead lentigines (P = 1.37 × 10(-8) ). The second block, within the 6p21 HLA region, was associated with decreased HLA-C expression according to several eQTL databases. Interestingly, these SNPs were also in high linkage disequilibrium with the HLA-C*0701 allele (r(2)  = 0.95). We replicated an association recently found by GWAS in the IRF4 gene. Finally, a complementary study on 44 selected candidate SNPs revealed novel associations in the MITF gene. Overall, our results point to several mechanisms involved in the severity of facial lentigines, including HLA/immunity and the melanogenesis pathway.

Sun-reactive Skin Type in 4912 French adults participating in the SU.VI.MAX study.

Phototype classifications were initially developed in an attempt to predict the skin reactions of patients to phototherapy and are now widely used to advise individuals with regard to sun protection. A transversal study was conducted on the SU.VI.MAX cohort to estimate the frequency of sun-reactive skin features in a large, general adult population-based sample, and to describe the associations between these features. The data were collected 3 years after the beginning of the SU.VI.MAX nutritional intervention study on 4912 volunteers (2868 women aged 35-60 years and 2044 men aged 45-60 years). A multiple correspondence analysis was performed to study the associations between the features. The results showed that these features correspond to a one-dimensional phenomenon, which allowed us to establish a score to summarize skin sensitivity to sun exposure. Furthermore, we found a link between gender and phototype using the Césarini classification (phototype > or = IV: 37% of women, 47% of men). The analysis of the relationship with sun-reactive skin features and the score revealed the same trend. Phenotypic evaluation appears to be a good estimator of skin sensitivity to sun exposure for clinical screening or for use in research, and is easy to collect at a lower cost. Moreover, the sun sensitivity difference between gender should be considered in education about photoprotection.

Determinants of vitamin D status in Caucasian adults: influence of sun exposure, dietary intake, sociodemographic, lifestyle, anthropometric, and genetic factors.

Very few studies have investigated the determinants of serum vitamin D levels using a set of variables that include simultaneously sun exposure, phototype, dietary intake, sociodemographics, anthropometric, lifestyle data, and genetic polymorphisms. Our objective was to investigate the associations between all these parameters and vitamin D status in a large sample of French adults. This cross-sectional survey was based on 1,828 middle-aged Caucasian adults from the SU.VI.MAX (SUpplémentation en VItamines et Minéraux AntioXydants) study. Plasma 25-hydroxyvitamin D (25OHD) concentration was lower among women (P<0.0001), older subjects (P=0.04), obese/underweight (P<0.0001), those living at higher latitudes (P<0.0001), those whose blood draw occurred in early spring (P<0.0001), less physically active (P<0.0001), with low sun exposure (P<0.0001), and with no-to-low alcohol intake (P=0.0001). Mutant GC rs4588 and rs7041 single nucleotide polymorphisms were associated with lower and higher 25OHD concentrations, respectively (P<0.0001). Dietary intake was not a major determinant of vitamin D status (P=0.7). This study provides an overall picture of determinants of vitamin D status. Several modifiable factors were identified, such as daily-life moderate sun exposure, physical activity, and normal-weight maintenance, which should be targeted by public health policies in order to improve vitamin D status in the general population, while avoiding active/intensive sun exposure, in line with recommendations for skin cancer prevention.

Relative contribution of intrinsic vs extrinsic factors to skin aging as determined by a validated skin age score.

OBJECTIVE: To assess the relative contribution of intrinsic aging vs lifestyle factors to facial skin age. DESIGN: Prospective analysis of a cohort. SETTING: Skin research institute. STUDY SUBJECTS: A cohort of 361 white women (age range, 18-80 years) with apparently healthy skin. MEASUREMENTS: Visual and tactile assessment of facial skin features. RESULTS: Twenty-four skin characteristics were used to build a skin age score (SAS). The relationship between the SAS and chronological age followed a linear model with 2 plateaus--1 before age 30 years and 1 after age 71 years. An analysis was performed to determine whether certain lifestyle habits known to have effects on skin aging were related to the discrepancies between chronological age and the SAS. Significant effects were identified for phototype, body mass index, menopausal status, degree of lifetime sun exposure, and number of years of cigarette smoking. However, these factors accounted for only 10% of the discrepancies. Moreover, most skin characteristics used reflected changes understood to represent intrinsic aging rather than photodamage or other extrinsic factors. CONCLUSIONS: An SAS can be generated from multiple discrete signs evaluated on facial skin and is an informative tool for quantifying skin aging. The SAS is influenced by factors already recognized to affect the aging phenotypes; however, factors related to the rate of intrinsic aging, presumably genetic in character, seem to play a larger role than previously suspected.

Association between dietary intake of n-3 polyunsaturated fatty acids and severity of skin photoaging in a middle-aged Caucasian population.

BACKGROUND: Intake of long-chain n-3 polyunsaturated fatty acid (PUFAs) supplementation has been reported to be associated with reduced UVB-erythemal sensitivity, but their relationship to photoaging has not been studied to date. OBJECTIVE: To investigate associations between daily n-3 PUFA intake and the severity of skin photoaging. METHODS: A cross-sectional study was conducted on 2919 subjects aged 45-60 years from the SU.VI.MAX cohort. At baseline, trained investigators graded the severity of facial skin photoaging using a validated 6-grade scale during a clinical examination. Intake of α-linolenic (ALA), eicosapentaenoic (EPA), docosapentaenoic (DPA), and docosahexaenoic acids (DHA) were evaluated by dietary source using ten 24-h dietary record questionnaires during the first 2.5 years of the follow-up period. RESULTS: After adjustment for possible confounders, severe photoaging was found to be inversely associated with higher intake of ALA in men and with higher intake of EPA in women. When considering the different food sources of ALA for men, an inverse association appeared between severe photoaging and ALA from vegetable oils, as well as with ALA from fruit and vegetables, whereas no association was observed for ALA from dairy products. In women, ALA from vegetable oils also tended to be inversely linked to photoaging. CONCLUSIONS: These findings suggest a possible benefit effect of n-3 PUFAs on skin aging. Nonetheless, further epidemiological studies are necessary to confirm our results and to gain additional insights into underlying mechanisms.

A genome-wide association study in Caucasian women points out a putative role of the STXBP5L gene in facial photoaging.

A genome-wide association study (GWAS) was conducted on 502 French middle-aged Caucasian women to identify genetic factors that may affect skin aging severity. A high-throughput Illumina Human Omni1-Quad beadchip was used. After single-nucleotide polymorphism (SNP) quality controls, 795,063 SNPs remained for analysis purposes. Possible stratification was first examined using the Eigenstrat method, and then the relationships between genotypes and four skin aging indicators (global photoaging, lentigines, wrinkles, and sagging) were investigated separately by linear regressions adjusted on age, smoking habits, lifetime sun exposure, hormonal status, and the two main Eigen vectors. One signal passed the Bonferroni threshold (P=1.53 × 10(-8)) and was significantly associated with global photoaging. It was also correlated with the wrinkling score and the sagging score. According to HapMap, this SNP, rs322458, was in linkage disequilibrium (LD) with intronic SNPs of the STXBP5L gene, which is expressed in the skin. In addition, it was also in LD with another SNP that increases the expression of the FBXO40 gene in the skin. These two genes, which were not previously described in the context of aging, may constitute good candidates for the investigation of molecular mechanisms of skin photoaging.

Dietary monounsaturated fatty acids intake and risk of skin photoaging.

BACKGROUND: Intake of monounsaturated fatty acids has been reported to reduce oxidative stress, insulin resistance and related inflammatory processes and may thus protect from skin photoaging. The objective of this study was to investigate the association between the risk of photoaging, monounsaturated fatty acids intake and the sources of monounsaturated fatty acids. METHODOLOGY/PRINCIPAL FINDINGS: A cross sectional study was conducted within the framework of the SUVIMAX cohort. The survey included 1264 women and 1655 men aged between 45 and 60 years old. Dietary monounsaturated fatty acids intakes were estimated by dietary source through at least ten 24-h diet records completed during the first 2.5 years of the follow-up period. Severity of facial skin photoaging was graded by trained investigators at baseline during a clinical examination using a 6-grade scale illustrated by photographs. A lower risk of severe photoaging was associated with higher intakes of monounsaturated fatty acids from olive oil in both sexes. Strikingly, no association was found with intake of monounsaturated fatty acids from animal sources whether from dairy products, meat or processed meat. CONCLUSION/SIGNIFICANCE: These findings support the beneficial effect of dietary olive oil or healthy diet habits associated with olive oil consumption on the severity of facial photoaging.

Incidence of skin cancers during 5-year follow-up after stopping antioxidant vitamins and mineral supplementation.

CONTEXT: In the SU.VI.MAX study, antioxidant supplementation for 7.5 years was found to increase skin cancer risk in women but not in men. OBJECTIVE: To investigate the potential residual or delayed effect of antioxidant supplementation on skin cancer incidence after a 5-year post-intervention follow-up. DESIGN, SETTING AND PARTICIPANTS: Assessment of skin cancer including melanoma and non-melanoma during the post-intervention follow-up (September 2002-August 2007). The SU.VI.MAX study was a double-blind, placebo-controlled, randomised trial, in which 12,741 French adults (7713 women aged 35-60 years and 5028 men aged 45-60 years) received daily a placebo or a combination of ascorbic acid (120 mg), vitamin E (30 mg), ß-carotene (6 mg), selenium (100 µg) and zinc (20mg), from inclusion in 1994 to September 2002. MAIN OUTCOME MEASURES: Total skin cancer incidence, including melanoma, squamous cell carcinoma and basal cell carcinoma. RESULTS: During the post-intervention period, 10 melanomas appeared in women and 9 in men (26 and 18, respectively, for the total period of supplementation+post-supplementation). Six squamous cell carcinomas were found in women and 15 in men (10 and 25, respectively, for the total period). Finally, 40 basal cell carcinomas appeared in women and 36 in men (98 and 94, respectively, for the total period). Regarding potential residual or delayed effects of supplementation in women, no increased risk of melanoma was observed during the post-intervention follow-up period. No delayed effects, either on melanoma or non-melanoma skin cancers, were observed for either gender. CONCLUSIONS: The risk of skin cancers associated with antioxidant intake declines following interruption of supplementation. This supports a causative role for antioxidants in the evolution of skin cancers.

Functional MC1R-gene variants are associated with increased risk for severe photoaging of facial skin.

The objective of this study was to assess the association between melanocortin-1 receptor (MC1R) variants and the severity of facial skin photoaging. The study population comprised 530 middle-aged French women. A trained dermatologist graded the severity of facial skin photoaging from photographs using a global scale. Logistic regressions were performed to assess the influence of MC1R polymorphisms on severe photoaging with adjustment for possible confounders (demographic and phenotypic data and sun exposure intensity). Among the fifteen MC1R variants identified, the nine most common were V60L, V92M, R151C, R160W, R163Q, R142H, D294H, D84E, and I155T. One hundred and eighty-five individuals (35%) were WT homozygotes, 261 (49%) had one common variant, 78 (15%) had two common variants, and six (1%) had at least one rare variant. After adjustment for possible confounders, the presence of two common variants was already a risk factor for severe photoaging (AOR (95% confidence interval): 2.33 (1.17-4.63)). This risk reached 5.61 (1.43-21.96) when two major diminished-function variants were present. Surprisingly, the minor variant, V92M, was associated with increased risk of photoaging (2.57 (1.23-5.35)). Our results suggest that genetic variations of MC1R are important determinants for severe photoaging.

MC1R gene polymorphism affects skin color and phenotypic features related to sun sensitivity in a population of French adult women.

The melanocortin-1 receptor (MC1R) gene is known to play a major role in skin and hair pigmentation and to be highly polymorphic in Caucasians. This study was performed to investigate the relationships between MC1R gene polymorphisms and skin color in a large sample of French middle-aged Caucasian women. The codons 60 to 265 and the codon 294 of the MC1R gene were sequenced in 488 women. The skin color was measured on the inner side of the forearm using a spectrophotometric instrument. Fifteen variants were identified: Arg151Cys, Arg160Trp, Arg142His, Asp294His, Ile155Thr, Asp84Glu, Val60Leu, Val92Met, Arg163Gln, Ser83Pro, Thr95Met, Pro256Ser, Val265Ile, Ala166Ala and Gln233Gln. Women carrying Arg151Cys, Asp294His, Arg160Trp and Asp84Glu variants had a significantly higher reflectance in the red region, which indicates a lower level of functional melanin. This association was the most pronounced for women carrying Asp84Glu. In contrast, no significant difference was observed for other variants. Moreover, associations between MC1R polymorphisms and the risks of experiencing sunburn and of having freckles were found independently of skin color. Our findings support the hypothesis that MC1R polymorphisms do not necessarily alter the skin color but should sensitize the skin to UV-induced DNA damage.