Effects of cosmetics on the skin microbiome of facial cheeks with different hydration levels

A Living Microecological Hydrogel with Microbiota Remodeling and Immune Reinstatement for Diabetic Wound Healing

Dysregulated skin microbiota and compromised immune responses are the major etiological factors for non-healing diabetic wounds. Current antibacterial strategies fail to orchestrate immune responses and indiscriminately eradicate bacteria at the wound site, exacerbating the imbalance of microbiota. Drawing inspiration from the beneficial impacts that probiotics possess on microbiota, a living microecological hydrogel containing Lactobacillus plantarum and fructooligosaccharide (LP/FOS@Gel) is formulated to remodel dysregulated skin microbiota and reinstate compromised immune responses, cultivating a conducive environment for optimal wound healing. LP/FOS@Gel acts as an "evocator," skillfully integrating the skin microecology, promoting the proliferation of Lactobacillus, Ralstonia, Muribaculum, Bacillus, and Allobaculum, while eradicating colonized pathogenic bacteria. Concurrently, LP/FOS@Gel continuously generates lactic acid to elicit a reparative macrophage response and impede the activation of the nuclear factor kappa-B pathway, effectively alleviating inflammation. As an intelligent microecological system, LP/FOS@Gel reinstates the skin's sovereignty during the healing process and effectively orchestrates the harmonious dialogue between the host immune system and microorganisms, thereby fostering the healing of diabetic infectious wounds. These remarkable attributes render LP/FOS@Gel highly advantageous for pragmatic clinical applications.

Metabolic relationships between marine red algae and algae-associated bacteria

Mutualistic interactions between marine phototrophs and associated bacteria are an important strategy for their successful survival in the ocean, but little is known about their metabolic relationships. Here, bacterial communities in the algal sphere (AS) and bulk solution (BS) of nine marine red algal cultures were analyzed, and Roseibium and Phycisphaera were identified significantly more abundantly in AS than in BS. The metabolic features of Roseibium RMAR6-6 (isolated and genome-sequenced), Phycisphaera MAG 12 (obtained by metagenomic sequencing), and a marine red alga, Porphyridium purpureum CCMP1328 (from GenBank), were analyzed bioinformatically. RMAR6-6 has the genetic capability to fix nitrogen and produce B vitamins (B1, B2, B5, B6, B9, and B12), bacterioferritin, dimethylsulfoniopropionate (DMSP), and phenylacetate that may enhance algal growth, whereas MAG 12 may have a limited metabolic capability, not producing vitamins B9 and B12, DMSP, phenylacetate, and siderophores, but with the ability to produce bacitracin, possibly modulating algal microbiome. P. purpureum CCMP1328 lacks the genetic capability to fix nitrogen and produce vitamin B12, DMSP, phenylacetate, and siderophore. It was shown that the nitrogen-fixing ability of RMAR6-6 promoted the growth of P. purpureum, and DMSP reduced the oxidative stress of P. purpureum. The metabolic interactions between strain RMAR6-6 and P. purpureum CCMP1328 were also investigated by the transcriptomic analyses of their monoculture and co-culture. Taken together, potential metabolic relationships between Roseibium and P. purpureum were proposed. This study provides a better understanding of the metabolic relationships between marine algae and algae-associated bacteria for successful growth.

Supplementary Information

The online version contains supplementary material available at 10.1007/s42995-024-00227-z.

Yeast mannan rich fraction positively influences microbiome uniformity, productivity associated taxa, and lay performance

BACKGROUND

Alternatives to antibiotic as growth promoters in agriculture, such as supplemental prebiotics, are required to maintain healthy and high performing animals without directly contributing to antimicrobial resistance bioburden. While the gut microbiota of broiler hens has been well established and successfully correlated to performance, to our knowledge, a study has yet to be completed on the effect of prebiotic supplementation on correlating the mature laying hen productivity and microbiota. This study focused on establishing the impact of a yeast derived prebiotic, mannan rich fraction (MRF), on the cecal microbiota of late laying hens. This study benefitted from large sample sizes so intra- and intergroup variation effects could be statistically accounted for.

RESULTS

Taxonomic richness was significantly greater at all taxonomic ranks and taxonomic evenness was significantly lower for all taxonomic ranks in MRF-supplemented birds (P < 0.005). Use of principal coordinate analyses and principal component analyses found significant variation between treatment groups. When assessed for compositional uniformity (an indicator of flock health), microbiota in MRF-supplemented birds was more uniform than control birds at the species level. From a food safety and animal welfare perspective, Campylobacter jejuni was significantly lower in abundance in MRF-supplemented birds. In this study, species associated with high weight gain (an anticorrelator of performance in laying hens) were significantly lower in abundance in laying hens while health-correlated butyrate and propionate producing species were significantly greater in abundance in MRF-supplemented birds.

CONCLUSIONS

The use of prebiotics may be a key factor in controlling the microbiota balance limiting agri-food chain pathogen persistence and in promoting uniformity. In previous studies, increased α- and β-diversity indices were determinants of pathogen mitigation and performance. MRF-supplemented birds in this study established greater α- and β-diversity indices in post-peak laying hens, greater compositional uniformity across samples, a lower pathogenic bioburden and a greater abundance of correlators of performance.

Skin aging-related microbial types separated by Cutibacterium and α-diversity

BACKGROUND

Studies on the skin microbiome have been conducted to uncover the relationship between skin microbes and the host. However, most of these studies have primarily focused on analyzing individual microbial compositions, which has resulted in a limited understanding of the overall relationship.

METHODS

We analyzed the facial skin characteristics and microbial profiles of 100 healthy Korean female volunteers using the V1-V2 region of the 16S ribosomal RNA gene.

RESULTS

The two most prominent features of the facial skin microbiome, the proportion of Cutibacterium and α-diversity, were associated with most of the skin characteristics. Based on clustering results, we proposed four types of facial skin microbiome: type C for Cutibacterium, type B for balanced, type CB for those between types C and B, and type O for others. Type C, which has a high proportion of Cutibacterium, showed high levels of pigmentation, wrinkles, pores, and sagging pores, indicating a tendency for severe skin aging. Type B, which has no dominant species and high microbial diversity, had lower values for pigmentation and wrinkles indicating less severe skin aging. Type CB was an intermediate type between type C and type B in terms of microbial composition and the level of skin aging. Type O dominated by microorganisms other than Cutibacterium, had high levels of sebum and pores but low levels of wrinkles.

CONCLUSION

We proposed a criterion for classifying facial skin microbial types, each of which showed distinct facial skin aging features. Our simplified microbial types will contribute to a better understanding of facial skin microbial studies.

Skin Deep: The Potential of Microbiome Cosmetics

The interplay between the skin microbiome and its host is a complex facet of dermatological health and has become a critical focus in the development of microbiome cosmetics. The skin microbiome, comprising various microorganisms, is essential from birth, develops over the lifespan, and performs vital roles in protecting our body against pathogens, training the immune system, and facilitating the breakdown of organic matter. Dysbiosis, an imbalance of these microorganisms, has been implicated in a number of skin conditions such as acne, atopic dermatitis, and skin cancer. Recent scientific findings have spurred cosmetic companies to develop products that preserve and enhance the skin's microbial diversity balance. These products may incorporate elements like prebiotics, probiotics, and postbiotics, which are beneficial for the skin microbiome. Beyond topical products, there's increasing interest in ingestible beauty supplements (i.e. oral probiotics), highlighting the connection between the gut and skin. This review examines the influence of the microbiome on skin health and the emerging trends of microbiome skincare products.

Longitudinal analysis of the skin microbiome in association with hand eczema, hand hygiene practices and moisturizer use

BACKGROUND

The skin microbiota maintains a physical and immunological barrier to the environment. Little is known about how the microbiome changes over time or the effect of hand hygiene practices and moisturizer use.

OBJECTIVES

To assess sex-specific changes in skin bacteria over time, and how the microbiome is related to self-reported hand eczema, hand hygiene practices and use of moisturizers.

METHODS

Swab samples from the dorsal hand were collected at baseline and 6.5 years later during the COVID-19 pandemic, in 168 participants from the RHINESSA study in Bergen, Norway. The skin samples were analysed by 16S rRNA amplicon sequencing.

RESULTS

The alpha diversity of the hand microbiome increased from baseline to follow-up, and beta diversity differed by sex at both time points. The relative abundance increased for several bacteria from baseline to follow-up, with sex-specific differences. Current hand eczema and aggravating hand eczema during the COVID-19 pandemic were associated with an increase in Staphylococcus. High hand washing frequency at home was associated with lower alpha diversity and with higher abundance of Staphylococcus, Corynebacterium, Finegoldia, and Pseudomonas and lower abundance of Propionibacterium and Pelomonas. The alpha diversity increased with increasing time passing between hand washing and sampling, whereas more frequent moisturizer use was associated with significantly lower alpha diversity, and a change in abundance for some bacteria, such as more Pseudomonas.

CONCLUSIONS

This longitudinal study revealed an overall increase in skin microbial diversity over a 6-year period, which was unexpected since follow-up was performed during the COVID-19 pandemic when vigorous hand hygienic practices were introduced. Sex-specific differences were identified at both time points. Individuals with hand eczema seem to develop a more dysbiotic skin bacterial community over time. Hand washing and use of moisturizers, with typically gender-specific habitual patterns, may lead to change in bacterial composition.

Skin Barrier-Enhancing Effects of Dermabiotics HDB with Regulation of Skin Microbiota

In the regulation of inflammatory responses and skin homeostasis, the skin and its microbiota are closely related. Studies have reported that lactic acid bacteria extracts can improve the skin condition and microbiota. In our previous study, we developed probiotic lysates, which are efficacious in improvement of human skin cells and the skin barrier. The skin-moisturizing effect of Dermabiotics HDB (HDB) prepared with Lactiplantibacillus plantarum, and the correlation between changes in the skin microbiota and moisture contents, were evaluated and analyzed in clinical trials. The clinical parameters on the cheeks of 21 female participants were measured using biophysical tools before and after (2 weeks) using HDB or control. The skin microbes were collected and identified using 16s rRNA gene sequencing. HDB significantly improved moisture intensity, transepidermal water loss (TEWL), and hot flush level on the cheek. The beta-diversity of the skin microbiota was different from that of the control in the unweighted UniFrac principal coordinate analysis after using HDB. The genus Lawsonella demonstrated a positive correlation with TEWL and a negative correlation with the moisture contents of the keratin layer, regardless of the use of HDB and control. Conversely, after HDB use, the genus Staphylococcus was increased and associated with a lower hot flush level, while the genera of the phylum Proteobacteria tended to decrease, which is associated with an improved skin condition. Overall, HDB showed clinically proven effects, including skin moisturization with regulation of the skin microbiota.

Impact of Leave-on Skin Care Products on the Preservation of Skin Microbiome: An Exploration of Ecobiological Approach

Purpose

Skincare products are used daily to maintain a healthy skin, although their skin microbiome impact is still poorly known. Preserving the natural resources and mechanisms of the skin ecosystem is essential, and a novel approach based on these premises, called ecobiology, has recently emerged in skincare. We evaluated the impact on the skin microbiome of three types of leave-on face skincare products: a hydrophilic solution, a micellar solution, and an oil-in-water emulsion.

Patients and Methods

Samples for microbial profiling were obtained from 20 Caucasian females twenty-four hours and four days following daily application of the skincare products and compared to an untreated area. The bacterial diversity and the abundance of the skin microbiome were analyzed by 16S rRNA gene sequencing using an Illumina MiSeq platform.

Results

Our results confirmed the skin microbiome diversity and the prevalence of Cutibacterium spp. and Staphylococcus spp. at sebaceous sites. The bacterial diversity and abundance were not affected by the products, and no dissimilarities versus the control nor between each product were noted at both times.

Conclusion

These preliminary results demonstrate for the first time that three types of leave-on face skincare products have no impact on the human skin microbiome and can be considered to be "microbiome friendly".

Effects of Investigational Moisturizers on the Skin Barrier and Microbiome following Exposure to Environmental Aggressors: A Randomized Clinical Trial and Ex Vivo Analysis

The skin microbiota barrier participates in skin barrier function in addition to the physical, chemical, and immunological protective barriers, and is affected by environmental aggressors and skincare regimens. To better understand the exact effects of real-life environmental conditions on the skin and determine the protective methods, this study investigates the effects of three topical cosmetic moisturizers (water gel moisturizers with/without yeast extract (Moisturizers K and C) and a thick-emulsion cream moisturizer (Moisturizer L)) on clinical and skin microbiome endpoints in the presence of environmental aggressors during an 8-week, randomized controlled, triple-blind clinical trial with 110 participants, and molecular- as well as biomarker-level endpoints on ex vivo skin explants after exposure to simulate urban environmental conditions. The results show that all moisturizers are well-tolerated and improve skin barrier function and surface moisture content from the baseline, and the improvement is maintained at the last analysis point (3 days after trial completion). Compared with the untreated control areas (samples taken from the upper chest), treatment with Moisturizer K prevented a reduction in bacterial and fungal richness, and increased the change ratio of the relative abundance of commensal bacteria, such as Staphylococcus epidermidis and Ralstonia, at the treated sites (samples taken from the forehead). Moreover, Moisturizer K-treated ex vivo skin explants had higher levels of caspase 14 (a marker of skin barrier function), collagen I, and elastin (structure components), and lower levels of aryl hydrocarbon receptor (AHR; activated by air pollutants) and interleukin-6 (IL-6) than those in explants treated with other moisturizers and in the untreated areas of the skin. These results suggest that a skin postbiotic moisturizer with yeast extract supports the regulation of the skin's microbiome balance and may provide a holistic barrier (involving skin microbiome, physical, chemical, and immune barriers) to protect the skin against environmental aggressors.

Pulmonary microbiota signatures adjacent to adenocarcinoma, squamous cell carcinoma and benign lesion

Introduction

The occurrence and progression of lung cancer are influenced by pulmonary microbiota, yet the relationship between changes in the pulmonary microbiota and lung cancer remains unclear.

Methods

To investigate the correlation between pulmonary microbiota and the signature of lung lesions, we analyzed the microbial composition at sites adjacent to the stage 1 adenocarcinoma, squamous carcinoma and benign lesion tissues in 49 patients by using 16S ribosomal RNA gene sequencing. We then conducted Linear discriminant analysis, receiver operating characteristic (ROC) curve analysis and PICRUSt prediction based on 16S sequencing results.

Results

Overall, the microbiota composition at sites close to lung lesions showed significant differences between different lesion types. Based on the results of LEfSe analysis, Ralstonia, Acinetobacter and Microbacterium are the dominant genera of lung adenocarcinoma (LUAD), lung squamous carcinoma (LUSC) and benign lesions (BENL), respectively. Furthermore, we determined the diagnostic value of the abundance ratio of Ralstonia to Acinetobacter in adenocarcinoma patients through ROC curve analysis. The PICRUSt analysis revealed 15 remarkably different metabolic pathways in these lesion types. In LUAD patients, the increase of the pathway associated with xenobiotic biodegradation may be due to the continuous proliferation of microbe with degradation ability of xenobiotics, which implied that LUAD patients are often exposed to harmful environment.

Discussion

The abundance of Ralstonia was related to the development of lung cancer. By measuring the abundance of microbiota in diseased tissues, we can distinguish between different types of lesions. The differences in pulmonary microbiota between lesion types are significant in understanding the occurrence and development of lung lesions.

Human skin bacterial microbiota homeostasis: A delicate balance between health and disease

As the largest organ of the body, the skin acts as a barrier to prevent diseases and harbors a variety of beneficial bacteria. Furthermore, the skin bacterial microbiota plays a vital role in health and disease. Disruption of the barrier or an imbalance between symbionts and pathogens can lead to skin disorders or even systemic diseases. In this review, we first provide an overview of research on skin bacterial microbiota and human health, including the composition of skin bacteria in a healthy state, as well as skin bacterial microbiota educating the immune system and preventing the invasion of pathogens. We then discuss the diseases that result from skin microbial dysbiosis, including atopic dermatitis, common acne, chronic wounds, psoriasis, viral transmission, cutaneous lupus, cutaneous lymphoma, and hidradenitis suppurativa. Finally, we highlight the progress that utilizes skin microorganisms for disease therapeutics, such as bacteriotherapy and skin microbiome transplantation. A deeper knowledge of the interaction between human health and disease and the homeostasis of the skin bacterial microbiota will lead to new insights and strategies for exploiting skin bacteria as a novel therapeutic target.

Oral and Topical Probiotics and Postbiotics in Skincare and Dermatological Therapy: A Concise Review

The skin microbiota is a pivotal contributor to the maintenance of skin homeostasis by protecting it from harmful pathogens and regulating the immune system. An imbalance in the skin microbiota can lead to pathological conditions such as eczema, psoriasis, and acne. The balance of the skin microbiota components can be disrupted by different elements and dynamics such as changes in pH levels, exposure to environmental toxins, and the use of certain skincare products. Some research suggests that certain probiotic strains and their metabolites (postbiotics) may provide benefits such as improving the skin barrier function, reducing inflammation, and improving the appearance of acne-prone or eczema-prone skin. Consequently, in recent years probiotics and postbiotics have become a popular ingredient in skincare products. Moreover, it was demonstrated that skin health can be influenced by the skin-gut axis, and imbalances in the gut microbiome caused by poor diet, stress, or the use of antibiotics can lead to skin conditions. In this way, products that improve gut microbiota balance have been gaining attention from cosmetic and pharmaceutical companies. The present review will focus on the crosstalk between the SM and the host, and its effects on health and diseases.

Randomized comparative double-blind study assessing the difference between topically applied microbiome supporting skincare versus conventional skincare on the facial microbiome in correlation to biophysical skin parameters

BACKGROUND

There are trillions of live bacteria, of around 1000 different species, living in human skin which are considered essential for the balance and barrier function of the skin. The gut microbiome has been a subject of extensive research and evidence shows that the gut flora is affected by preservatives and processed foods. In conventional skincare, preservatives are used, and this raises the question of how it affects the skin flora and its balance.

METHODS

A randomized double-blind study on 14 healthy volunteers ages 23-45 years old were advised to use microbiome-supporting (MS) products on one cheek and benchmark (BM) products on the other cheek daily for 3 weeks. To investigate how the skin was affected, the skin microbiome was analysed using 16 S rRNA sequencing and biophysical parameters were assessed using an Antera 3D camera. Measurements were performed before and after the 3 weeks of using the products.

RESULTS

The use of MS products for 3 weeks significantly increased the total number of reads mapped to unique bacterial species (p < 0.05) and the number of different unique species (p < 0.05). In addition, the use of MS products significantly reduced redness (p < 0.05) and improved skin texture (p < 0.01). The use of BM products showed no significant difference in any of the parameters except improved skin texture (p < 0.05). Additionally, the MS side showed a significantly improved diversity (p < 0.05) compared with the BM side. The four major phyla found were, similarly to previous findings by others, Actinobacteria, Firmicutes, Proteobacteria and Bacteroidetes. Some of the most prevalent species were Cutibacterium acnes, Staphylococcus epidermidis and Pseudonomas aeruginosa.

CONCLUSION

The findings of this study showed significant improvements in the microbiome and biophysical parameters within 3 weeks of using MS skincare alone, while BM skincare only gave significantly improved skin roughness. Importantly, the MS side gave a significantly improved bacterial Shannon diversity (p < 0.05) compared with the BM side. Regarding the biophysical parameters, the MS skincare gave significant improvements in several parameters compared with baseline. However, they were not yet significant when compared to using BM skincare and therefore a larger study population will be needed. Importantly, this is the first study to investigate how preservatives affect the facial microbiome in vivo and has raised a need for further investigation. These results together with further studies can lead to innovations within the cosmetic industry that promote healthier skin.

Sodium hyaluronates applied in the face affects the diversity of skin microbiota in healthy people

OBJECTIVE

A healthy and stable microbiome has many beneficial effects on the host, while an unbalanced or disordered microbiome can lead to various skin diseases. Hyaluronic acid is widely used in the cosmetics and pharmaceutical industries; however, specific reports on its effect on the skin microflora of healthy people have not been published. This study aimed to determine the effect of sodium hyaluronate on the facial microflora of healthy individuals.

METHODS

Face of 20 healthy female volunteers between 18 and 24 years was smeared with sodium hyaluronate solution once per day. Cotton swabs were used to retrieve samples on days 0, 14, and 28, and high-throughput sequencing of 16 S rRNA was used to determine the changes in bacterial community composition.

RESULTS

Facial application of HA can reduce the abundance of pathogenic bacteria, such as Cutibacterium and S. aureus, and increase the colonization of beneficial bacteria.

CONCLUSION

This is the first intuitive report to demonstrate the effect of hyaluronic acid on facial microflora in healthy people. Accordingly, sodium hyaluronate was found to have a positive effect on facial skin health.

Stabilization of Acne Vulgaris-Associated Microbial Dysbiosis with 2% Supramolecular Salicylic Acid

Facial microbiota dysbiosis is an important factor in causing acne vulgaris. The present study aimed to analyze the effect of 2% Supramolecular Salicylic Acid (SSA) on acne-associated facial bacteria. In the current study, 30 acne vulgaris patients (treated with 2% SSA for eight weeks) and ten volunteers with no facial acne were selected. Samples from acne patients (before and after treatment) and volunteers (not treated) were analyzed via high throughput sequencing, Deblur algorithm, and R microbiome package. After treatment with 2% SSA, the total lesion count and global acne grading system (GAGS) score reduced significantly (p < 0.001). Metagenomic sequencing analysis revealed that the pre-treated acne group had low α and deviated β diversity compared to the control and post-treated acne groups. Due to the treatment with 2% SSA, α diversity index was increased and β diversity was stabilized significantly (p < 0.001). The relative abundance of bacterial genera in the pre-treated acne group was uneven and had a high proportion of Staphylococcus, Ralstonia, and Streptococcus. The proportion of these three genera was significantly decreased in the post-treated group, and overall bacteria genera distribution tends toward the healthy individual. It is concluded that 2% SSA normalizes the microbial communities associated with the skin.

5-α reductase inhibition by Epilobioum fleischeri extract modulates facial microbiota structure

Background

Facial skin is a particularly complex environment made of different skin types such as sebaceous (forehead) and dry (cheeks). The skin microbiota composition on different facial sites has not yet been addressed.

Methods

We conducted a 4‐week‐long, single‐centre, randomized and placebo‐controlled clinical study involving 23 Caucasian females. We assessed both bacterial composition on five different facial areas and the microbiome modulatory effects resulting from the topical application of a plant extract (Epilobium fleischeri). Skin microbiome samples were collected before and after 4 weeks of product application. Microbiota profiling was performed via 16S rRNA gene sequencing, and relative abundance data were used to calculate differentials via a multinomial regression model.

Results

Via ‘reference frames’, we observed shifts in microbial composition after 4 weeks of twice‐daily product application and identify certain microbiota species, which were positively associated with the application of the product containing the Epilobium fleischeri extract. Staphylococcus hominis, Staphylococcus epidermidis, and Micrococcus yunnanensis appeared to be significantly enriched in the final microbiota composition of the active treatment group.

Conclusion

Facial skin was found to be colonized by an heterogenous microbiota, and the Epilobium fleischeri extract had a modulatory effect on commensal bacteria on the different facial sites.

Changes in the use of cosmetics worldwide due to increased use of masks in the coronavirus disease‐19 pandemic

Background

According to recent experience, people are willing to wear masks to protect themselves from environmental issues such as infections, allergies, and fine dust such as SARS in 2003, swine flu A (H1N1) in 2009, and COVID‐19 in 2019.

Objectives

The objective of this study was to investigate the changing conditions of cosmetics use worldwide due to the increase in mask usage.

Methods

This review paper is a literature review, and a narrative review approach has been used for this study. A total of 300–400 references were selected using representative journal search websites such as PubMed, Google Scholar, Scopus, and RISS, of which a total of 39 papers were selected in the final stage based on 2006–2021.

Results

Masks must be worn due to environmental issues and/or infectious diseases, for example, COVID‐19. Skin troubles were dramatically increased by the increased use of masks. Additionally, research‐related natural products for skin soothing ingredients and makeup products were suggested.

Conclusion

This review is expected to be used as an important marketing material for new changes in the cosmetics market by clearly grasping the needs of consumers in the beauty and cosmetics industry from the viewpoint of using masks after COVID‐19.

Advances in Microbiome-Derived Solutions and Methodologies Are Founding a New Era in Skin Health and Care

The microbiome, as a community of microorganisms and their structural elements, genomes, metabolites/signal molecules, has been shown to play an important role in human health, with significant beneficial applications for gut health. Skin microbiome has emerged as a new field with high potential to develop disruptive solutions to manage skin health and disease. Despite an incomplete toolbox for skin microbiome analyses, much progress has been made towards functional dissection of microbiomes and host-microbiome interactions. A standardized and robust investigation of the skin microbiome is necessary to provide accurate microbial information and set the base for a successful translation of innovations in the dermo-cosmetic field. This review provides an overview of how the landscape of skin microbiome research has evolved from method development (multi-omics/data-based analytical approaches) to the discovery and development of novel microbiome-derived ingredients. Moreover, it provides a summary of the latest findings on interactions between the microbiomes (gut and skin) and skin health/disease. Solutions derived from these two paths are used to develop novel microbiome-based ingredients or solutions acting on skin homeostasis are proposed. The most promising skin and gut-derived microbiome interventional strategies are presented, along with regulatory, safety, industrial, and technical challenges related to a successful translation of these microbiome-based concepts/technologies in the dermo-cosmetic industry.

Pilot Study on the Forehead Skin Microbiome and Short Chain Fatty Acids Depending on the SC Functional Index in Korean Cohorts

Dry skin is one of the indicators of a compromised skin barrier. An intact skin barrier is not only important to reserve the hydration within the epidermal tissue but also to protect our skin from environmental stressors and inhibit pathogen invasion; damage to the skin barrier may lead to inflammatory skin diseases. Some microbial metabolites such as short chain fatty acids may inhibit or destroy harmful bacteria and regulate the host immune system. The impact of the skin microbiome and short chain fatty acids on skin barrier function was studied in two groups of 75 participants each. The cohort was equally divided in dry and moist skin types, based on stratum corneum (SC) functionality index (SCFI), reflecting the ratio of transepidermal water loss (TEWL). A dry group represents a low SCFI and a moist group a high SCFI. Compared with the dry skin group, propionate and Cutibacterium levels (previously known as Propionibacterium acnes) were significantly higher (p < 0.001) in the moist group. Levels of Cutibacterium were negatively correlated with those of Staphylococcus (p < 0.0001) in both dry and moist groups. The moist group also had a significantly higher propionate concentration (p < 0.001). This study showed that the microbial community and short chain fatty acid concentration may be considered as significant determinants of the SCFI of the skin.

Patients with senile pruritus have a distinct skin microbiota and epidermal barrier in comparison with healthy controls

Senile pruritus (SP) is a common skin disease in the elderly. The role of skin dysbacteriosis in the development of various skin diseases has been studied in recent years. However, the research about the skin microbiota of senile pruritus patients is lacking at present. The purpose of this cross-sectional study was to investigate the differences of skin microbiota in senile pruritus patients and their relationship with the epidermal barrier. Thirty patients with senile pruritus and 30 age- and sex-matched healthy controls were enrolled in this study. The skin barrier indexes were recorded by multi-functional skin tester. The skin bacterial diversity was analyzed by using hyper-variable tag sequencing of the V3-V4 region of the 16S rDNA. Compared with the healthy control group, the patients had significantly lower skin hydration (p = 0.014) and higher pH value (p = 0.021). Skin microbial diversity was significantly increased in patients according to the alpha diversity. At the genus level, Acinetobacter (p = 0.002) and Lactobacillus (p = 0.002) increased and Cutibacterium (p = 0.043) decreased. The pH value was positively associated with observed_species diversity (p = 0.026). The transdermal water loss was negatively related to the genus of Lactobacillus (p = 0.036), while the skin hydration was positively associated with the genus of Lactobacillus (p = 0.038). As a result, the damaged skin barrier function and skin dysbacteriosis complemented each other and may be associated with the occurrence of senile pruritus, but their role still needs further study.

Effect of the skincare product on facial skin microbial structure and biophysical parameters: A pilot study

Daily use of cosmetics is known to affect the skin microbiome. This study aimed to determine the bacterial community structure and skin biophysical parameters following the daily application of a skincare product on the face. Twenty-five Korean women, who used the same skincare product for four weeks participated in the study. During this period, skin hydration, texture, sebum content, and pH were measured, and skin swab samples were collected on the cheeks. The microbiota was analyzed using the MiSeq system. Through these experiments, bacterial diversity in facial skin increased and the microbial community changed after four weeks of skincare product application. The relative abundance of Cutibacterium and Staphylococcus increased, significant changes in specific bacterial modules of the skin microbial network were observed, and skin hydration and texture improved. It was suggested that daily use of skincare products could affect the microbial structure of facial skin as well as the biophysical properties of the facial skin. These findings expand our understanding of the role of skincare products on the skin environment.

Effects of Heat-Killed Lactococcus lactis Strain Plasma on Skin Homeostasis-Related Genes and the Skin Microbiome among Healthy Adults: A Randomized Controlled Double-Blind Study

Lactococcus lactis subsp. lactis strain plasma (LC-plasma) is a bacterial strain that activates plasmacytoid dendritic cells and induces viral resistance genes via the TLR9/MyD88 pathway. We recently showed that oral administration of LC-plasma prevents skin infection by Staphylococcus aureus, possibly by activating skin immunity. In this study, we conducted a double-blind clinical trial to investigate the effect of oral administration of heat-killed LC-plasma on the skin microbiome, gene expression in the skin, and the skin condition of healthy volunteers. Seventy healthy volunteers were randomly assigned to receive either heat-killed LC-plasma or a placebo for eight weeks. Analysis of the skin microbiome by next-generation sequencing suggested that the alpha-diversity of the skin microbiome did not change during the test period in either group. However, the proportion of species that changed significantly during the test period was 10-fold smaller in the LC-plasma group than in the placebo group, suggesting that LC-plasma may maintain the skin microbiome. Quantitative PCR analysis indicated that tight-junction genes, such as CLDN1 and CLDN12, and the antimicrobial peptide gene BD3 were significantly up-regulated in the LC-plasma group but not in the placebo group. Our results suggest that administration of LC-plasma helps to maintain the skin microbiome and that it affects homeostasis-related genes.

A Journey on the Skin Microbiome: Pitfalls and Opportunities

The human skin microbiota is essential for maintaining homeostasis and ensuring barrier functions. Over the years, the characterization of its composition and taxonomic diversity has reached outstanding goals, with more than 10 million bacterial genes collected and cataloged. Nevertheless, the study of the skin microbiota presents specific challenges that need to be addressed in study design. Benchmarking procedures and reproducible and robust analysis workflows for increasing comparability among studies are required. For various reasons and because of specific technical problems, these issues have been investigated in gut microbiota studies, but they have been largely overlooked for skin microbiota. After a short description of the skin microbiota, the review tackles methodological aspects and their pitfalls, covering NGS approaches and high throughput culture-based techniques. Recent insights into the "core" and "transient" types of skin microbiota and how the manipulation of these communities can prevent or combat skin diseases are also covered. Finally, this review includes an overview of the main dermatological diseases, the changes in the microbiota composition associated with them, and the recommended skin sampling procedures. The last section focuses on topical and oral probiotics to improve and maintain skin health, considering their possible applications for skin diseases.

Skin microbiota dynamics following B. subtilis formulation challenge: an in vivo study in mice

BACKGROUND

Modulating the microbiota is a leading-edge strategy for the restoration and maintenance of a healthy, balanced environment. The use of health-promoting bacteria has demonstrated some potential benefits as an alternative for skin microbiota intervention. Here, we investigate the manipulation of mice skin microbiota using B. subtilis incorporated into a supportive Pluronic F-127 hydrogel formulation. The formula plays an important role in delivering the bacteria to the desired action site.

RESULTS

The B. subtilis challenge induced a shift in the composition and abundance of the skin microbiota. Containment of B. subtilis in the Pluronic F-127 hydrogel accelerated bacterial modulation compared with free B. subtilis. The abundance of both Staphylococcus and Corynebacterium spp. was altered as a result of the live bacterial intervention: the abundance of Corynebacterium increased while that of Staphylococcus decreased. Four days after last application of the B. subtilis formulation, B. subtilis counts returned to its initial level.

CONCLUSIONS

B. subtilis intervention can induce a shift in the skin microbiota, influencing the abundance of commensal, beneficial, and pathogenic bacteria. Containment of B. subtilis in Pluronic hydrogel accelerates the microbial alteration, probably by facilitating bacterial attachment and supporting continuous growth. Our results reveal the ability of B. subtilis in Pluronic to modulate the skin microbiota composition, suggesting that the formulation holds therapeutic potential for skin disease treatment.

The power and potential of BIOMAP to elucidate host-microbiome interplay in skin inflammatory diseases

The two most common chronic inflammatory skin diseases are atopic dermatitis (AD) and psoriasis. The underpinnings of the remarkable degree of clinical heterogeneity of AD and psoriasis are poorly understood and, as a consequence, disease onset and progression are unpredictable and the optimal type and time-point for intervention are as yet unknown. The BIOMAP project is the first IMI (Innovative Medicines Initiative) project dedicated to investigating the causes and mechanisms of AD and psoriasis and to identify potential biomarkers responsible for the variation in disease outcome. The consortium includes 7 large pharmaceutical companies and 25 non-industry partners including academia. Since there is mounting evidence supporting an important role for microbial exposures and our microbiota as factors mediating immune polarization and AD and psoriasis pathogenesis, an entire work package is dedicated to the investigation of skin and gut microbiome linked to AD or psoriasis. The large collaborative BIOMAP project will enable the integration of patient cohorts, data and knowledge in unprecedented proportions. The project has a unique opportunity with a potential to bridge and fill the gaps between current problems and solutions. This review highlights the power and potential of BIOMAP project in the investigation of microbe-host interplay in AD and psoriasis.

Apple cider vinegar soaks do not alter the skin bacterial microbiome in atopic dermatitis

INTRODUCTION

Atopic dermatitis is a common skin disease characterized by altered cutaneous immunity in which patients often exhibit lower skin microbiota diversity compared to healthy skin and are prone to colonization by Staphylococcus aureus. Apple cider vinegar has been shown to have antibacterial effects; however, its effects on the skin microbiome have not previously been well-described.

OBJECTIVES

We aimed to examine the effects of topical dilute apple cider vinegar soaks on Staphylococcus aureus abundance, skin bacterial microbiome composition, and skin bacterial microbiome diversity in atopic dermatitis participants compared to healthy skin.

METHODS

Eleven subjects with atopic dermatitis and 11 healthy controls were enrolled in this randomized, non-blinded, single-institution, split-arm pilot study. Subjects soaked one forearm in dilute apple cider vinegar (0.5% acetic acid) and the other forearm in tap water for 10 minutes daily. Skin bacteria samples were collected from subjects' volar forearms before and after 14 days of treatment. 16S sequencing was used to analyze Staphylococcus aureus abundance and skin bacterial microbiome composition, and alpha diversity of microbiota were determined using Shannon diversity index.

RESULTS

There was no difference in skin bacterial microbiome in atopic dermatitis subjects after 2 weeks of daily water or apple cider vinegar treatments (p = 0.056 and p = 0.22, respectively), or in mean abundance of S. aureus on apple cider vinegar-treated forearms (p = 0.60). At 2 weeks, the skin bacterial microbiomes of healthy control subjects were not significantly different from the skin bacterial microbiome of atopic dermatitis subjects (p = 0.14, 0.21, 0.12, and 0.05).

CONCLUSIONS

Our results suggest that daily soaks in 0.5% apple cider vinegar are not an effective method of altering the skin bacterial microbiome in atopic dermatitis. Further studies are needed to explore the effects of different concentrations of apple cider vinegar on skin microflora and disease severity.

TRIAL NUMBER

UVA IRB-HSR #19906.

Challenges in exploring and manipulating the human skin microbiome

The skin is the exterior interface of the human body with the environment. Despite its harsh physical landscape, the skin is colonized by diverse commensal microbes. In this review, we discuss recent insights into skin microbial populations, including their composition and role in health and disease and their modulation by intrinsic and extrinsic factors, with a focus on the pathobiological basis of skin aging. We also describe the most recent tools for investigating the skin microbiota composition and microbe-skin relationships and perspectives regarding the challenges of skin microbiome manipulation. Video abstract.

Effect of a bioconverted product of Lotus corniculatus seed on the axillary microbiome and body odor

The skin microbiome, especially the axillary microbiome, consists of odor-causing bacteria that decompose odorless sweat into malodor compounds, which contributes to the formation of body odor. Plant-derived products are a cheap source of bioactive compounds that are common ingredients in cosmetics. Microbial bioconversion of natural products is an ecofriendly and economical method for production of new or improved biologically active compounds. Therefore, in this study, we tested the potential of a Lactobacillus acidophilus KNU-02-mediated bioconverted product (BLC) of Lotus corniculatus seed to reduce axillary malodor and its effect on the associated axillary microbiota. A chemical profile analysis revealed that benzoic acid was the most abundant chemical compound in BLC, which increased following bioconversion. Moreover, BLC treatment was found to reduce the intensity of axillary malodor. We tested the axillary microbiome of 18 study participants, divided equally into BLC and placebo groups, and revealed through 16S rRNA gene sequencing that Staphylococcus, Corynebacterium, and Anaerococcus were the dominant taxa, and some of these taxa were significantly associated with axillary malodor. After one week of BLC treatment, the abundance of Corynebacterium and Anaerococcus, which are associated with well-known odor-related genes that produce volatile fatty acids, had significantly reduced. Likewise, the identified odor-related genes decreased after the application of BLC. BLC treatment enhanced the richness and network density of the axillary microbial community. The placebo group, on the other hand, showed no difference in the microbial richness, odor associated taxa, and predicted functional genes after a week. The results demonstrated that BLC has the potential to reduce the axillary malodor and the associated odor-causing bacteria, which makes BLC a viable deodorant material in cosmetic products.

Longitudinal study of the scalp microbiome suggests coconut oil to enrich healthy scalp commensals

Dandruff is a recurrent chronic scalp disorder, affecting majority of the population worldwide. Recently a metagenomic study of the Indian scalp microbiome described an imperative role of bacterial commensals in providing essential vitamins and amino acids to the scalp. Coconut oil and its formulations are commonly applied on the scalp in several parts of the world to maintain scalp health. Thus, in this study we examined the effect of topical application of coconut oil on the scalp microbiome (bacterial and fungal) at the taxonomic and functional levels and their correlation with scalp physiological parameters. A 16-weeks-long time-course study was performed including 12-weeks of treatment and 4-weeks of relapse phase on a cohort of 140 (70 healthy and 70 dandruff) Indian women, resulting in ~ 900 metagenomic samples. After the treatment phase, an increase in the abundance of Cutibacterium acnes and Malassezia globosa in dandruff scalp was observed, which were negatively correlated to dandruff parameters. At the functional level, an enrichment of healthy scalp-related bacterial pathways, such as biotin metabolism and decrease in the fungal pathogenesis pathways was observed. The study provides novel insights on the effect of coconut oil in maintaining a healthy scalp and in modulating the scalp microbiome.

Taxonomic and Functional Characteristics of the Gill and Gastrointestinal Microbiota and Its Correlation with Intestinal Metabolites in NEW GIFT Strain of Farmed Adult Nile Tilapia (Oreochromis niloticus)

The gill and gastrointestinal tract are primary entry routes for pathogens. The symbiotic microbiota are essential to the health, nutrition and disease of fish. Though the intestinal microbiota of Nile tilapia (Oreochromis niloticus) has been extensively studied, information on the mucosa-associated microbiota of this species, especially the gill and gastrointestinal mucosa-associated microbiota, is lacking. This study aimed to characterize the gill and gastrointestinal mucosa- and digesta-associated microbiota, as well as the intestinal metabolite profiles in the New Genetically Improved Farmed Tilapia (NEW GIFT) strain of farmed adult Nile tilapia by high-throughput sequencing and gas chromatography/mass spectrometry metabolomics. The diversity, structure, composition, and predicted function of gastrointestinal microbiota were significantly different across gastrointestinal regions and sample types (Welch t-test; p < 0.05). By comparing the mucosa- and digesta-associated microbiota, linear discriminant analysis (LDA) effect size (LEfSe) analysis revealed that Pelomonas, Ralstoniapickettii, Comamonadaceae, and Staphylococcus were significantly enriched in the mucosa-associated microbiota, whereas many bacterial taxa were significantly enriched in the digesta-associated microbiota, including Chitinophagaceae, Cetobacterium, CandidatusCompetibacter, Methyloparacoccus, and chloroplast (LDA score > 3.5). Furthermore, Undibacterium, Escherichia-Shigella, Paeniclostridium, and Cetobacterium were dominant in the intestinal contents and mucosae, whereas Sphingomonasaquatilis and Roseomonasgilardii were commonly found in the gill and stomach mucosae. The Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt2) analysis revealed that the predictive function of digesta-associated microbiota significantly differed from that of mucosa-associated microbiota (R = 0.8152, p = 0.0001). In addition, our results showed a significant interdependence between specific intestinal microbes and metabolites. Notably, the relative abundance values of several potentially beneficial microbes, including Undibacterium, Crenothrix, and Cetobacterium, were positively correlated with most intestinal metabolites, whereas the relative abundance values of some potential opportunistic pathogens, including Acinetobacter, Mycobacterium, Escherichia-Shigella, Paeniclostridium, Aeromonas, and Clostridiumsensustricto 1, were negatively correlated with most intestinal metabolites. This study revealed the characteristics of gill and gastrointestinal mucosa-associated and digesta-associated microbiota of farmed Nile tilapia and identified a close correlation between intestinal microbes and metabolites. The results serve as a basis for the effective application of targeted probiotics or prebiotics in the diet to regulate the nutrition and health of farmed tilapia.

Human Skin Microbiome: Impact of Intrinsic and Extrinsic Factors on Skin Microbiota

The skin is the largest organ of the human body and it protects the body from the external environment. It has become the topic of interest of researchers from various scientific fields. Microorganisms ensure the proper functioning of the skin. Of great importance, are the mutual relations between such microorganisms and their responses to environmental impacts, as dysbiosis may contribute to serious skin diseases. Molecular methods, used for microorganism identification, allow us to gain a better understanding of the skin microbiome. The presented article contains the latest reports on the skin microbiota in health and disease. The review discusses the relationship between a properly functioning microbiome and the body's immune system, as well as the impact of internal and external factors on the human skin microbiome.

Skin and Gut Microbiome in Psoriasis: Gaining Insight Into the Pathophysiology of It and Finding Novel Therapeutic Strategies

Psoriasis affects the health of myriad populations around the world. The pathogenesis is multifactorial, and the exact driving factor remains unclear. This condition arises from the interaction between hyperproliferative keratinocytes and infiltrating immune cells, with poor prognosis and high recurrence. Better clinical treatments remain to be explored. There is much evidence that alterations in the skin and intestinal microbiome play an important role in the pathogenesis of psoriasis, and restoration of the microbiome is a promising preventive and therapeutic strategy for psoriasis. Herein, we have reviewed recent studies on the psoriasis-related microbiome in an attempt to confidently identify the “core” microbiome of psoriasis patients, understand the role of microbiome in the pathogenesis of psoriasis, and explore new therapeutic strategies for psoriasis through microbial intervention.

Microbial Biosurfactants in Cosmetic and Personal Skincare Pharmaceutical Formulations

Cosmetic and personal care products are globally used and often applied directly on the human skin. According to a recent survey in Europe, the market value of cosmetic and personal care products in Western Europe reached about 84 billion euros in 2018 and are predicted to increase by approximately 6% by the end of 2020. With these significant sums of money spent annually on cosmetic and personal care products, along with chemical surfactants being the main ingredient in a number of their formulations, of which many have been reported to have the potential to cause detrimental effects such as allergic reactions and skin irritations to the human skin; hence, the need for the replacement of chemical surfactants with other compounds that would have less or no negative effects on skin health. Biosurfactants (surfactants of biological origin) have exhibited great potential such as lower toxicity, skin compatibility, protection and surface moisturizing effects which are key components for an effective skincare routine. This review discusses the antimicrobial, skin surface moisturizing and low toxicity properties of glycolipid and lipopeptide biosurfactants which could make them suitable substitutes for chemical surfactants in current cosmetic and personal skincare pharmaceutical formulations. Finally, we discuss some challenges and possible solutions for biosurfactant applications.

Staphylococcus epidermidis and Cutibacterium acnes: Two Major Sentinels of Skin Microbiota and the Influence of Cosmetics

Dermatological and cosmetics fields have recently started to focus on the human skin microbiome and microbiota, since the skin microbiota is involved in the health and dysbiosis of the skin ecosystem. Amongst the skin microorganisms, Staphylococcus epidermidis and Cutibacterium acnes, both commensal bacteria, appear as skin microbiota sentinels. These sentinels have a key role in the skin ecosystem since they protect and prevent microbiota disequilibrium by fighting pathogens and participate in skin homeostasis through the production of beneficial bacterial metabolites. These bacteria adapt to changing skin microenvironments and can shift to being opportunistic pathogens, forming biofilms, and thus are involved in common skin dysbiosis, such as acne or atopic dermatitis. The current evaluation methods for cosmetic active ingredient development are discussed targeting these two sentinels with their assets and limits. After identification of these objectives, research of the active cosmetic ingredients and products that maintain and promote these commensal metabolisms, or reduce their pathogenic forms, are now the new challenges of the skincare industry in correlation with the constant development of adapted evaluation methods.

Microbial Reference Frames Reveal Distinct Shifts in the Skin Microbiota after Cleansing

Skin cleansing represents a process of mechanical and chemical removal of dirt, pollutants as well as microbiota from the skin. While skin cleansing can help maintain good health, protect us from infections, illnesses and ailments, skin cleansing can also strip away lipids and moisture from the skin, leading to irritation, barrier impairment and disturbance of the delicate cutaneous microbiome. This study investigated how skin cleansing impacts skin’s microbial composition. Thirty Caucasian women were enrolled in a placebo controlled clinical study where participants applied on their volar forearms a liquid body wash twice daily for 1 week in order to mimic frequent showering. Skin microbiome samples were collected by swabbing at defined timepoints and 16S rRNA sequencing was performed. Using “reference frames”, we could identify shifts in the microbial composition and several microbiota were identified as being characteristically associated with the presence of saccharide isomerate, a well-known skin moisturizer. The microbial shift was quite immediate, and we could observe it already at 1 h post cleansing. Interestingly, the new microbial composition reached a certain dynamic equilibrium at day 1 which was then maintained until the end of the study. Paracoccus marcusii, a potentially beneficial carotenoid-producer microorganism, was enriched by the active treatment and, at the same time, the abundance of several potential pathogenic taxa, Brevibacterium casei and Rothia mucilaginosa, diminished.

Human Skin Bacterial Community Response to Probiotic (Lactobacillus reuteri DSM 17938) Introduction

The introduction of a strain or consortium has often been considered as a potential solution to restore microbial ecosystems. Extensive research on the skin microbiota has led to the development of probiotic products (with live bacterial strains) that are likely to treat dysbiosis. However, the effects of such introductions on the indigenous microbiota have not yet been investigated. Here, through a daily application of Lactobacillus reuteri DSM 17938 on volunteers’ forearm skin, we studied in vivo the impact of a probiotic on the indigenous skin bacterial community diversity using Terminal-Restriction Fragment Length Polymorphism (T-RFLP) for 3 weeks. The results demonstrate that Lactobacillus reuteri DSM 17938 inoculum had a transient effect on the indigenous community, as the resilience phenomenon was observed within the skin microbiota. Moreover, Lactobacillus reuteri DSM 17938 monitoring showed that, despite a high level of detection after 2 weeks of application, thereafter the colonization rate drops drastically. The probiotic colonization rate was correlated significantly to the effect on the indigenous microbial community structure. These preliminary results suggest that the success of probiotic use and the potential health benefits resides in the interactions with the human microbiota.

Extrinsic Factors Shaping the Skin Microbiome

Human skin, our most environmentally exposed organ, is colonized by a vast array of microorganisms constituting its microbiome. These bacterial communities are crucial for the fulfillment of human physiological functions such as immune system modulation and epidermal development and differentiation. The structure of the human skin microbiome is established during the early life stages, starting even before birth, and continues to be modulated throughout the entire life cycle, by multiple host-related and environmental factors. This review focuses on extrinsic factors, ranging from cosmetics to the environment and antibacterial agents, as forces that impact the human skin microbiome and well-being. Assessing the impact of these factors on the skin microbiome will help elucidate the forces that shape the microbial populations we coexist with. Furthermore, we will gain additional insight into their tendency to stimulate a healthy environment or to increase the propensity for skin disorder development.

Unsaturated fatty acid-enriched extract from Hippophae rhamnoides seed reduces skin dryness through up-regulating aquaporins 3 and hyaluronan synthetases 2 expressions

Background

Seed oil of sea buckthorn (SBT) is well known to contain high amount of polyunsaturated fatty acid (PUFA), and PUFA is generally acknowledged to promote skin hydration by reducing trans‐epidermal water loss (TEWL).

Aims

The present study is aimed to investigate that skin hydration offered by SBT seed oil is whether through up‐regulating AQP3 or HAS2 expression.

Methods

MTT assay was performed to detect cytotoxicity of SBT seed oil, and then, PCR was carried out to explore whether SBT seed oil can increase AQP3 mRNA expression in normal human epidermis keratinocytes (NHEK) cells or not. Immunofluorescence (IF) and Western blot analysis were used to test the protein level expression of AQP3 and HAS2 influenced by SBT seed oil in NHEK cells or in reconstructed epidermis skin model.

Results

According to the result of MTT assay, all test concentration of SBT seed oil showed no cytotoxicity to cells. 10 μg/mL SBT seed oil treatment evidently increased AQP3 mRNA level compared to negative control (NC). IF and Western blot analysis results demonstrated that AQP3 and HAS2 protein levels in NHEK cells treated with 10 μg/mL SBT seed oil were much higher than that of NC. Finally, treatment with 10 μg/mL SBT seed oil substantially up‐regulated expression of AQP3 and HAS2 protein in reconstructed epidermis skin model in comparison to NC.

Conclusions

In summary, our study first proved that SBT seed oil can improve skin hydration through increasing AQP3 and HAS2 expressions.

Randomized double-blind vehicle controlled study of the effects of topical acetyl zingerone on photoaging

OBJECTIVE

Acetyl zingerone (AZ), a derivative of the phytochemical zingerone from Zingiber officinale (ginger), is a novel compound that is purported to have antiaging properties. The objective of this clinical study was to assess the role of acetyl zingerone in its ability to improve the appearance of facial skin wrinkles, redness, pigmentation, and photoaging was assessed.

METHODS

Thirty-one healthy participants (age 44 ± 7 years) were randomized in blinded fashion to apply either 1% AZ or placebo, consisting of the vehicle base cream, to the full face twice daily for 8 weeks with a total of 3 visits. Signs of photoaging, including wrinkles, dyspigmentation, and redness were assessed with facial image analysis photography and software.

RESULTS

There was a significant decrease in average wrinkle severity (P = .019; Mean=-25.7% change), total wrinkle volume (P = .003; Mean=-30.1% change), pigment intensity (P = .021; Mean=-25.6% change), and redness intensity (P = .035; Mean=-20.7% change) in the AZ group by 8 weeks compared with the placebo. No significant itching, burning, or stinging was noted by study participants. There was also no significant difference between both groups in the clinical assessment of scaling, erythema, hypopigmentation, or hyperpigmentation.

CONCLUSIONS AND RELEVANCE

Topical AZ improves photodamage and decreases the appearance of wrinkles, dyspigmentation, and redness intensity when compared to placebo (vehicle) formulation. Acetyl zingerone is well tolerated with daily use.

Effect of Porcine Placenta Extract Supplement on Skin Condition in Healthy Adult Women: A Randomized, Double-Blind Placebo-Controlled Study

Placenta extract has been used as a component of ointments for skin dryness and beautification. However, little is known about the effect of oral intake of placenta extract on skin condition. The current study aimed to clinically explore the effect of oral intake of porcine placenta extract on human skin quality. A randomized controlled double-blind trial was performed on healthy women aged 40–59 years (n = 20), who were randomly assigned to receive either placebo or 200 mg of porcine placenta extract once daily for 4 weeks from 28 January 2019 to 25 February 2019. Skin quality parameters and the Simplified Menopausal Index (SMI) were assessed at baseline and after 4 weeks. After 4 weeks, three parameters of skin quality were significantly improved in the porcine placenta group compared with the placebo group. These results suggest that porcine placenta extract can be used as a health food ingredient to maintain humans’ skin condition in the dry winter season.

Distinct Skin Microbiome and Skin Physiological Functions Between Bedridden Older Patients and Healthy People: A Single-Center Study in Japan

With the increase in the older populations, the number of bedridden older patients is becoming a matter of concern. Skin microbiome and skin physiological functions are known to change according to lifestyle and community; however, such changes in case of movement- and cleaning-restricted bedridden older patients have not yet been revealed. To address this issue, we analyzed skin microbiome and skin physiological functions, including pH, hydration, sebum level, and transepidermal water loss (TEWL), of bedridden older patients, compared with those of ambulatory older and young individuals. For this analysis, we enrolled 19 healthy young and 18 ambulatory older individuals from the community and 31 bedridden older patients from a single, long-term care hospital in Japan. The area of interest was set to the sacral (lower back) skin, where pressure injuries (PIs) and subsequent infection frequently occurs in bedridden older patients. We observed a higher number of gut-related bacteria, fewer commensals, higher skin pH, and lower TEWL on the sacral skin of bedridden older patients than on that of young or ambulatory older individuals. In addition, we observed that 4 of the 31 bedridden older patients developed PIs during the research period; a higher abundance of pathogenic skin bacteria were also observed inside the PI wounds. These findings imply distinct skin microbiome and skin physiological functions in bedridden older patients in comparison with healthy individuals and may suggest the need for more stringent cleaning of the skin of bedridden older patients in light of the closeness of skin and wound microbiome.

Dominance of Gas-Eating, Biofilm-Forming Methylobacterium Species in the Evaporator Cores of Automobile Air-Conditioning Systems

Air-conditioning systems (ACS) are indispensable for human daily life; however, microbial community analysis in automobile ACS has yet to be comprehensively investigated. A bacterial community analysis of 24 heat exchanger fins from five countries (South Korea, China, the United States, India, and the United Arab Emirates [UAE]) revealed that Methylobacterium species are some of the dominant bacteria in automobile ACS. Furthermore, we suggested that the predominance of Methylobacterium species in automobile ACS is due to the utilization of mixed volatile organic compounds and their great ability for aggregation and biofilm formation.

Microbial communities in the evaporator core (EC) of automobile air-conditioning systems have a large impact on indoor air quality, such as malodor and allergenicity. DNA-based microbial population analysis of the ECs collected from South Korea, China, the United States, India, and the United Arab Emirates revealed the extraordinary dominance of Methylobacterium species in EC biofilms. Mixed-volatile organic compound (VOC) utilization and biofilm-forming capabilities were evaluated to explain the dominance of Methylobacterium species in the ECs. The superior growth of all Methylobacterium species could be possible under mixed-VOC conditions. Interestingly, two lifestyle groups of Methylobacterium species could be categorized as the aggregator group, which sticks together but forms a small amount of biofilm, and the biofilm-forming group, which forms a large amount of biofilm, and their genomes along with phenotypic assays were analyzed. Pili are some of the major contributors to the aggregator lifestyle, and succinoglycan exopolysaccharide production may be responsible for the biofilm formation. However, the coexistence of these two lifestyle Methylobacterium groups enhanced their biofilm formation compared to that with each single culture.

IMPORTANCE Air-conditioning systems (ACS) are indispensable for human daily life; however, microbial community analysis in automobile ACS has yet to be comprehensively investigated. A bacterial community analysis of 24 heat exchanger fins from five countries (South Korea, China, the United States, India, and the United Arab Emirates [UAE]) revealed that Methylobacterium species are some of the dominant bacteria in automobile ACS. Furthermore, we suggested that the predominance of Methylobacterium species in automobile ACS is due to the utilization of mixed volatile organic compounds and their great ability for aggregation and biofilm formation.

Segregation of age-related skin microbiome characteristics by functionality

Although physiological changes are the most evident indicators of skin aging by alteration of the skin’s structure and function, we question whether skin aging is also affected by the structure and assembly process of the skin microbiome. We analysed the skin microbiomes of 73 healthy Chinese women in two age groups (25–35 years old and 56–63 years old) using 16S rRNA gene amplicon sequencing; the overall microbiome structure was significantly different between the two age groups. An analysis using ecological theory to evaluate the process of microbial community assembly processes revealed that the microbiomes of the older group were formed under a greater influence of the niche-based process, with the network of microbes being more collapsed than that of the younger group. Inferred metagenomic functional pathways associated with replication and repair were relatively more predominant in the younger group whereas, among the various metabolism-related pathways, those associated with biodegradation were more predominant in the older group. Interestingly, we found two segregated sub-typing patterns in the younger group which were also observed in the skin microbiomes of young Chinese women living in four other cities in China. The results of our study highlights candidate microbes and functional pathways that are important for future research into preventing skin aging and which could lead to a comprehensive understanding of age-related skin microbiome characteristics.

Consumer Safety Considerations of Skin and Oral Microbiome Perturbation

Microbiomes associated with human skin and the oral cavity are uniquely exposed to personal care regimes. Changes in the composition and activities of the microbial communities in these environments can be utilized to promote consumer health benefits, for example, by reducing the numbers, composition, or activities of microbes implicated in conditions such as acne, axillary odor, dandruff, and oral diseases. It is, however, important to ensure that innovative approaches for microbiome manipulation do not unsafely disrupt the microbiome or compromise health, and where major changes in the composition or activities of the microbiome may occur, these require evaluation to ensure that critical biological functions are unaffected. This article is based on a 2-day workshop held at SEAC Unilever, Sharnbrook, United Kingdom, involving 31 specialists in microbial risk assessment, skin and oral microbiome research, microbial ecology, bioinformatics, mathematical modeling, and immunology. The first day focused on understanding the potential implications of skin and oral microbiome perturbation, while approaches to characterize those perturbations were discussed during the second day. This article discusses the factors that the panel recommends be considered for personal care products that target the microbiomes of the skin and the oral cavity.

Impact of Selected Cosmetic Ingredients on Common Microorganisms of Healthy Human Skin

Human skin is a complex ecosystem and is host to a large number of microorganisms. When the bacterial ecosystem is balanced and differentiated, skin remains healthy. However, the use of cosmetics can change this balance and promote the appearance of skin diseases. The skin’s microorganisms can utilize some cosmetic components, which either promote their growth, or produce metabolites that influence the skin environment. In this study, we tested the ability of the Malassezia species and some bacterial strains to assimilate substances frequently used in dermal formulations. The growth capability of microorganisms was determined and their lipase activity was analyzed. The growth of all Malassezia spp. in the presence of free acids, free acid esters, and fatty alcohols with a fatty chain length above 12 carbon atoms was observed. No growth was observed in the presence of fatty alcohol ethers, secondary fatty alcohols, paraffin- and silicon-based substances, polymers, polyethylene glycols, quaternary ammonium salts, hydroxy fatty acid esters, or fatty acids and fatty acid esters with a fatty chain length shorter than 12 carbon atoms. The hydrolysis of esters by Malassezia lipases was detected using High Performance Thin Layer Chromatography (HPTLC). The production of free fatty acids as well as fatty alcohols was observed. The growth promotion or inhibition of bacterial strains was only found in the presence of a few ingredients. Based on these results, formulations containing microbiome inert ingredients were developed.

New Insights into the Intrinsic and Extrinsic Factors That Shape the Human Skin Microbiome

Many studies have highlighted the importance of body site and individuality in shaping the composition of the human skin microbiome, but we still have a poor understanding of how extrinsic (e.g., lifestyle) and intrinsic (e.g., age) factors influence its composition. We characterized the bacterial microbiomes of North American volunteers at four skin sites and the mouth. We also collected extensive subject metadata and measured several host physiological parameters. Integration of host and microbial features showed that the skin microbiome was predominantly associated with demographic, lifestyle, and physiological factors. Furthermore, we uncovered reproducible associations between chronological age, skin aging, and members of the genus Corynebacterium. Our work provides new understanding of the role of host selection and lifestyle in shaping skin microbiome composition. It also contributes to a more comprehensive appreciation of the factors that drive interindividual skin microbiome variation.

Despite recognition that biogeography and individuality shape the function and composition of the human skin microbiome, we know little about how extrinsic and intrinsic host factors influence its composition. To explore the contributions of these factors to skin microbiome variation, we profiled the bacterial microbiomes of 495 North American subjects (ages, 9 to 78 years) at four skin surfaces plus the oral epithelium using 16S rRNA gene amplicon sequencing. We collected subject metadata, including host physiological parameters, through standardized questionnaires and noninvasive biophysical methods. Using a combination of statistical modeling tools, we found that demographic, lifestyle, and physiological factors collectively explained 12 to 20% of the variability in microbiome composition. The influence of health factors was strongest on the oral microbiome. Associations between host factors and the skin microbiome were generally dominated by operational taxonomic units (OTUs) affiliated with the Clostridiales and Prevotella. A subset of the correlations between microbial features and host attributes were site specific. To further explore the relationship between age and the skin microbiome of the forehead, we trained a Random Forest regression model to predict chronological age from microbial features. Age was associated mostly with two mutually coexcluding Corynebacterium OTUs. Furthermore, skin aging variables (wrinkles and hyperpigmented spots) were independently correlated to these taxa.

Paraben Toxicology

Parabens now being formally declared as the American Contact Dermatitis Society (non)allergen of the year, the allergologic concerns regarding parabens raised during the past century are no longer a significant issue. The more recent toxicological concerns regarding parabens are more imposing, stemming from the gravity of the noncutaneous adverse health effects for which they have been scrutinized for the past 20 years. These include endocrine activity, carcinogenesis, infertility, spermatogenesis, adipogenesis, perinatal exposure impact, and nonallergologic cutaneous, psychologic, and ecologic effects. To assert that parabens are safe for use as currently used in the cosmetics, food, and pharmaceutical industries, all toxicological end points must be addressed. We seek to achieve perspective through this exercise: perspective for the professional assessing systemic risk of parabens by all routes of exposure. The data reviewed in this article strive to provide a balanced perspective for the consumer hopefully to allay concerns regarding the safety of parabens and facilitate an informed decision-making process. Based on currently available scientific information, claims that parabens are involved in the genesis or propagation of these controversial and important health problems are premature. Haste to remove parabens from consumer products could result in their substitution with alternative, less proven, and potentially unsafe alternatives, especially given the compelling data supporting the lack of significant dermal toxicity of this important group of preservatives.

Cosmetics in use: a pharmacological review

Cosmetics" really comes from its utilization in Ancient Rome. They were commonly delivered by female slaves known as "cosmetae," which is the place "cosmetics" originated from. Cosmetics are utilized to upgrade appearance. Makeup has been around for a long time. The primary known individuals who utilized cosmetics to upgrade their beauty were the Egyptians. Makeup those days was simply basic eye shading or some material for the body. Presently a-days makeup assumes an imperative job for the two men and women. In developmental brain science, social challenge of appearance reinforces women's wants for perfect beauty. As indicated by "The Origin of Species", people have developed to exchange qualities to future ages through sexual determination that respects the body state of perfect beauty as astounding richness. Also, since women's beauty has as of late been viewed as an upper hand to make social power, a body that satisfies the social guidelines of a culture could accomplish restricted social assets. It's hard to believe, but it’s true, even men have turned out to be more beauty cognizant and are worried about their looks. Cosmetics can be delivered in the natural and hypoallergenic structure to fulfill the needs of clients. Makeup is utilized as a beauty help to help develop the self-esteem and certainty of a person. The significance of cosmetics has expanded the same number of individuals need to remain youthful and alluring. Cosmetics are promptly accessible today as creams, lipstick, scents, eye shadows, nail shines, hair showers and so forth. Different cosmetics like face powder offer gleam to the skin subsequent to applying the base cream. At that point we have lipsticks, which are connected by numerous women all things considered. They are produced using wax and cocoa butter in the ideal sum. Cosmetics like creams, gels, and colognes are utilized consistently by the two women and men. Creams go about as a chemical for the face as a rule. All the more as of late enemy of maturing creams have been made which can hold more youthful looking skin for a long time. The best cleansing specialists are cleansing cream, cleanser and water. Cosmetic creams fill in as skin sustenance for hard, dry and dry skin. It fundamentally greases up, diminishes and expels undesirable earth from the skin. Some famous fat creams that are utilized incorporate Vaseline and Lanolin. Dry creams are utilized in the assembling of cleanser and gelatin which is utilized as a base for the skin. Hair care has turned out to be one of the quickest creating markets in the beauty business. Numerous young fellows swing to oils and gels to keep up and style their hair. Items like hair gels, oils, and moisturizers have been acquainted in the market with assistance ensure hair fall and dandruff. A few callings, similar to the entertainment biz industry, center on the significance of the external appearance. Numerous identities and craftsmen have used makeup to beat the brutal lights and the glare of camera flashes. They know the significance of their looks and keep up them by utilizing an assortment of cosmetics. Their appearance is their most profitable resource and they accept each undertaking to show up as the fans need them to show up. Late research has demonstrated that makeup helps in assurance from destructive beams of the sun. Numerous beauty items producers have used the necessities of individuals to shield themselves and their skin from the beams of the sun. This is an extraordinary achievement on the grounds that prior make up and sun assurance could not mix together. Today Cosmetics help to upgrade our appearance and make us feel increasingly certain. With more cosmetics available today than any other time in recent memory, it ends up clear to us that they assume an extraordinary job in our regular daily existence (Figure 1).

Structural and Functional Analysis of the Gut Microbiome for Toxicologists

Characterizing the reciprocal interactions between toxicants, the gut microbiota, and the host, holds great promise for improving our mechanistic understanding of toxic endpoints. Advances in culture-independent sequencing analysis (e.g., 16S rRNA gene amplicon sequencing) combined with quantitative metabolite profiling (i.e., metabolomics) have provided new ways of studying the gut microbiome and have begun to illuminate how toxicants influence the structure and function of the gut microbiome. Developing a standardized protocol is important for establishing robust, reproducible, and importantly, comparative data. This protocol can be used as a foundation for examining the gut microbiome via sequencing-based analysis and metabolomics. Two main units follow: (1) analysis of the gut microbiome via sequencing-based approaches; and (2) functional analysis of the gut microbiome via metabolomics. © 2018 by John Wiley & Sons, Inc.

Effects of cosmetics on the skin microbiome of facial cheeks with different hydration levels

Basic cosmetics was used by volunteers belonging to high (HHG) and low (LHG) hydration groups for 4 weeks, and bacterial communities and biophysical parameters in facial skin were analyzed. Hydration level increases and transepidermal water loss and roughness decreases were observed in both groups after cosmetic use. Bacterial diversity was greater in LHG than HHG, and increased after cosmetic use in both groups. Bray–Curtis dissimilarities that were higher in LHG than HHG increased in HHG after cosmetic use, whereas they decreased in LHG. The phyla Actinobacteria, Proteobacteria, Firmicutes, and Bacteroidetes and the genera Propionibacterium, Ralstonia, Burkholderia, Staphylococcus, Corynebacterium, Cupriavidus, and Pelomonas were identified as common groups and they were not significantly different between LHG and HHG except for Propionibacterium that was more abundant in HHG. After cosmetic use, Propionibacterium, Staphylococcus, and Corynebacterium decreased, whereas Ralstonia, not a core genus, increased, as did KEGG categories of lipid metabolism and xenobiotics biodegradation and metabolism, suggesting that Ralstonia in skin may have the ability to metabolize cosmetics components. Bacterial communities after cosmetic use were different from those in both LHG and HHG before the cosmetic use, indicating that bacterial communities in LHG were not shifted to resemble those in HHG by cosmetics use.