Potential Clinical Applications of the Postbiotic Butyrate in Human Skin Diseases

Alterations of circulating free fatty acids in patients with pemphigus vulgaris

Free fatty acids (FFA) have gained research interest owing to their functions in both local and systemic immune regulation. Changes in the serum levels of anti-inflammatory short chain fatty acids (SCFA), primarily derived from the gut microbiota, and pro-inflammatory medium (MCFA) and long (LCFA) chain fatty acids, derived from either the gut microbiota or the diet, have been associated with autoimmunity. Circulating FFA were retrospectively analysed by a gas chromatography-mass spectrometry method in the serum of 18 patients with pemphigus vulgaris (PV) at the baseline and 6 months (n = 10) after immunosuppressive treatments, and 18 healthy controls (HC). Circulating FFA were correlated with the Pemphigus Disease Area Index (PDAI) and serum concentrations of interferon-gamma (IFN-γ), Interleukin (IL)-17A, IL-5, IL-10 and IL-21. Principal Component analysis computed on FFA abundances revealed significant differences in the profile of SCFA (p = 0,012), MCFA (p = 0.00015) and LCFA (p = 0,035) between PV patients and HC, which were not significantly changed by immunosuppressive treatments. PV patients showed a significantly lower serum concentration of propionic (p < 0.0005) and butyric (p < 0.0005) acids, SCFA with anti-inflammatory functions, while hexanoic (p < 0.0005) and hexadecanoic (p = 0.0006) acids, pro-inflammatory MCFA and LCFA respectively, were over-represented. Treatments induced a significant decrease of hexanoic (p = 0.035) and a further increase of hexadecanoic (p = 0.046) acids. Positive correlations emerged between IFN-γ and acetic acid (Rho = 0.60), IFN-γ and hexanoic acid (Rho = 0.46), IL-5 and both hexadecanoic acid (Rho = 0.50) and octadecanoic acid (Rho = 0.53), butyric acid and PDAI (Rho = 0.53). PV was associated with a remarked imbalance of circulating FFA compared to HC. The serum alterations of SCFA, MCFA, and LCFA may contribute to promoting inflammation in PV. Deeper insights into the immunomodulatory functions of these molecules may pave the way for personalized dietary interventions in PV patients.

The Real-World Effectiveness and Tolerability of a Soothing Cream Containing the Postbiotic Aquaphilus dolomiae Extract-G2 for Skin Healing

INTRODUCTION

In vitro and pre-marketing clinical data have shown the healing properties of a postbiotic extract from Aquaphilus dolomiae (ADE-G2). The effectiveness and tolerability of an ADE-G2-based cream were therefore evaluated for the management of minor skin impairment and wound healing in a large population of subjects in routine clinical practice.

METHODS

A real-world, international, pre-post comparative study was conducted in infants, children, and adults with various types of superficial skin impairment who used the study product daily for around 3 weeks according to their dermatologist's advice. Immediate and follow-up changes in dermatologic signs and symptoms were assessed through clinical scoring. User satisfaction, overall product effectiveness, and tolerability were also evaluated. Analyses were performed in the whole study population and in subject subgroups according to skin impairment type and age.

RESULTS

Overall, 1317 subjects (83.1% adults, 72.0% female) were included. Dermatologists reported effectiveness and "good" or "very good" tolerability of the cream in 93.8% (1221/1302) and 98.5% (1278/1297) of subjects, respectively. Immediate symptom relief after the first application was reported by 88.3% (849/962) of subjects. After several weeks of regular use (16.7 ± 11.6 days), dermatologic signs and symptoms significantly improved in the whole study population and in the subgroups, with mean decreases in severity scores ranging from -34.5% to -92.5% (p < 0.0001). The smallest improvements were found in subjects with oncologic treatment-related skin impairment. At study end, most users (> 95%) were "very satisfied" or "satisfied" with the cream and found that skin healing was rapid and of good quality.

CONCLUSION

The ADE-G2-based cream proved to be effective and well tolerated in real-life conditions for the management of minor skin impairment in a large and varied cohort of subjects. This product, used as a standalone or adjunctive regimen, can help accelerate the healing of various types of superficial skin impairment.

The old friends hypothesis: evolution, immunoregulation and essential microbial inputs

In wealthy urbanised societies there have been striking increases in chronic inflammatory disorders such as allergies, autoimmunity and inflammatory bowel diseases. There has also been an increase in the prevalence of individuals with systemically raised levels of inflammatory biomarkers correlating with increased risk of metabolic, cardiovascular and psychiatric problems. These changing disease patterns indicate a broad failure of the mechanisms that should stop the immune system from attacking harmless allergens, components of self or gut contents, and that should terminate inappropriate inflammation. The Old Friends Hypothesis postulates that this broad failure of immunoregulation is due to inadequate exposures to the microorganisms that drive development of the immune system, and drive the expansion of components such as regulatory T cells (Treg) that mediate immunoregulatory mechanisms. An evolutionary approach helps us to identify the organisms on which we are in a state of evolved dependence for this function (Old Friends). The bottom line is that most of the organisms that drive the regulatory arm of the immune system come from our mothers and family and from the natural environment (including animals) and many of these organisms are symbiotic components of a healthy microbiota. Lifestyle changes that are interrupting our exposure to these organisms can now be identified, and many are closely associated with low socioeconomic status (SES) in wealthy countries. These insights will facilitate the development of education, diets and urban planning that can correct the immunoregulatory deficit, while simultaneously reducing other contributory factors such as epithelial damage.

Efficacy and Safety of Epidermidibacterium Keratini EPI-7 Derived Postbiotics in Skin Aging: A Prospective Clinical Study

The present study investigated the effect of topical application of Epidermidibacterium Keratini (EPI-7) ferment filtrate, which is a postbiotic product of a novel actinobacteria, on skin aging, by performing a prospective randomized split-face clinical study on Asian woman participants. The investigators measured skin biophysical parameters, including skin barrier function, elasticity, and dermal density, and revealed that the application of the EPI-7 ferment filtrate-including test product resulted in significantly higher improvements in barrier function, skin elasticity, and dermal density compared to the placebo group. This study also investigated the influence of EPI-7 ferment filtrate on skin microbiome diversity to access its potential beneficial effects and safety. EPI-7 ferment filtrate increased the abundance of commensal microbes belonging to Cutibacterium, Staphylococcus, Corynebacterium, Streptococcus, Lawsonella, Clostridium, Rothia, Lactobacillus, and Prevotella. The abundance of Cutibacterium was significantly increased along with significant changes in Clostridium and Prevotella abundance. Therefore, EPI-7 postbiotics, which contain the metabolite called orotic acid, ameliorate the skin microbiota linked with the aging phenotype of the skin. This study provides preliminary evidence that postbiotic therapy may affect the signs of skin aging and microbial diversity. To confirm the positive effect of EPI-7 postbiotics and microbial interaction, additional clinical investigations and functional analyses are required.

The role of short-chain fatty acids in inflammatory skin diseases

Short-chain fatty acids (SCFAs) are metabolites of gut microbes that can modulate the host inflammatory response, and contribute to health and homeostasis. Since the introduction of the gut-skin axis concept, the link between SCFAs and inflammatory skin diseases has attracted considerable attention. In this review, we have summarized the literature on the role of SCFAs in skin inflammation, and the correlation between SCFAs and inflammatory skin diseases, especially atopic dermatitis, urticaria, and psoriasis. Studies show that SCFAs are signaling factors in the gut-skin axis and can alleviate skin inflammation. The information presented in this review provides new insights into the molecular mechanisms driving gut-skin axis regulation, along with possible pathways that can be targeted for the treatment and prevention of inflammatory skin diseases.

Therapeutic effects elicited by the probiotic Lacticaseibacillus rhamnosus GG in children with atopic dermatitis. The results of the ProPAD trial

BACKGROUND

Atopic dermatitis (AD) is a chronic inflammatory skin disease affecting up to 20% of the pediatric population associated with alteration of skin and gut microbiome. Probiotics have been proposed for AD treatment. The ProPAD study aimed to investigate the therapeutic effects of the probiotic Lacticaseibacillus rhamnosus GG (LGG) in children with AD.

METHODS

In total, 100 AD patients aged 6-36 months were enrolled in a randomized, double-blind, controlled trial to receive placebo (Group A) or LGG (1 x 10¹⁰ CFU/daily) (Group B) for 12 weeks. The primary outcome was the evaluation of the efficacy of LGG supplementation on AD severity comparing the Scoring Atopic Dermatitis (SCORAD) index at baseline (T0) and at 12-week (T12). A reduction of ≥8.7 points on the SCORAD index was considered as minimum clinically important difference (MCID). The secondary outcomes were the SCORAD index evaluation at 4-week (T16) after the end of LGG treatment, number of days without rescue medications, changes in Infant Dermatitis Quality Of Life questionnaire (IDQOL), gut microbiome structure and function, and skin microbiome structure.

RESULTS

The rate of subjects achieving MCID at T12 and at T16 was higher in Group B (p < .05), and remained higher at T16 (p < .05)The number of days without rescue medications was higher in Group B. IDQOL improved at T12 in the Group B (p < .05). A beneficial modulation of gut and skin microbiome was observed only in Group B patients.

CONCLUSIONS

The probiotic LGG could be useful as adjunctive therapy in pediatric AD. The beneficial effects on disease severity and quality of life paralleled with a beneficial modulation of gut and skin microbiome.