Search Results (46)

Bullous pemphigoid (BP) and pemphigus vulgaris (PV) represent the most prevalent conditions among autoimmune bullous skin diseases, considered a major cause of severe morbidity and, in certain cases, mortality. The hallmark of the two diseases is the presence of autoantibodies directed against proteins located in the basement membrane of the skin, which determines the formation of blisters. In recent years, interest in the role of microbiota in relation to health-disease status has progressively increased. In particular, based on the gut–skin axis, accumulating evidence has emerged on the potential association between the composition and diversity of microbial communities in the gut, skin, and even in the oral cavity and the risk of developing BP and PV. Dysbiosis, characterized by a generally higher relative abundance of Firmicutes and a depletion of probiotics/beneficial species, might contribute to the pathogenesis of both diseases. Despite the still limited number of studies and the need for further large-scale multicenter studies, the knowledge gathered so far is suggestive of a novel modifiable risk factor representing a potential target for adjuvant treatments of these disabling and life-threatening conditions. Full article

Prebiotic oligosaccharides have attracted significant interest in dermatology and skin health due to their ability to modulate the skin microbiome and microbiota–host interactions. This review offers a novel dual perspective, systematically examining the benefits of both oral intake and topical application of prebiotic oligosaccharides, including well-established prebiotics (e.g., human milk oligosaccharides, galacto- and fructo-oligosaccharides) and emerging prebiotic candidates (e.g., gluco-oligosaccharides, chitosan-oligosaccharides, agaro-oligosaccharides). First, cutting-edge synthetic processes for producing diverse oligosaccharides and their structural chemistry are introduced. Then, we discuss in vitro studies demonstrating their efficacy in promoting skin commensals, inhibiting pathogens, and conferring protective effects, such as antioxidant, anti-inflammatory, anti-melanogenic, and wound-healing properties. Furthermore, we emphasize in vivo animal studies and clinical trials revealing that prebiotic oligosaccharides, administered orally or topically, alleviate atopic dermatitis, enhance skin hydration, attenuate acne, and protect against photo-aging by modulating skin–gut microbiota and immune responses. Mechanistically, we integrate genetic and molecular insights to elucidate how oligosaccharides mediate these benefits, including gut–skin axis crosstalk, immune regulation, and microbial metabolite signaling. Finally, we highlight current commercial applications of oligosaccharides in cosmetic formulations while addressing scientific and practical challenges, such as structure–function relationships, clinical scalability, and regulatory considerations. This review bridges mechanistic understanding with practical applications, offering a comprehensive resource for advancing prebiotic oligosaccharides-based skincare therapies. Full article

Background: Melanoma, one of the most aggressive forms of skin cancer, has seen significant therapeutic advances with immune checkpoint inhibitors (ICIs). However, many patients fail to respond or develop resistance, creating the need for adjunct strategies. Objective: The objective of this study is to critically evaluate how specific dietary patterns and nutrient-derived metabolites modulate melanoma metabolism and immunotherapy outcomes, emphasizing translational implications. Methods: We performed an integrative review of preclinical and clinical studies investigating dietary interventions in melanoma models and ICI-treated patients. Mechanistic insights were extracted from studies on nutrient transport, immunometabolism, and microbiome–immune interactions, including data from ongoing nutritional clinical trials. Results: Diets rich in fermentable fibers, plant polyphenols, and unsaturated lipids, such as Mediterranean and ketogenic diets, seem to contribute to the reprogramming of tumor metabolism and enhance CD8+ T-cell activity. Fasting-mimicking and methionine-restricted diets modulate T-cell fitness and tumor vulnerability via nutrient stress sensors (e.g., UPR, mTOR). High fiber intake correlates with favorable gut microbiota and improved ICI efficacy, while excess protein, methionine, or refined carbohydrates impair immune surveillance via lactate accumulation and immunosuppressive myeloid recruitment. Several dietary molecules act as network-level modulators of host and microbial proteins, with parallels to known drug scaffolds. Conclusions: Integrating dietary interventions into melanoma immunotherapy can significantly influence metabolic reprogramming by targeting metabolic vulnerabilities and reshaping the tumor–immune–microbiome axis. When combined with AI-driven nutrient–protein interaction mapping, this approach offers a precision nutrition paradigm that supports both physicians and patients, emerging as a novel layer to enhance and consolidate existing therapeutic strategies. Full article

The extensive research and studies conducted over the past decade have greatly improved our comprehension of the pathogenesis and risk factors associated with Spondyloarthritis (SpA). In addition, they have contributed to the advancement of novel therapeutic approaches. Although genetics still represents the primary risk factor for SpA, increasing evidence presented in this review suggests that environmental factors—such as air pollution, smoking, gut microbiota (GM), infections, and diet—also contribute to its pathogenesis. In detail, environmental particulate matters (PMs), which include ligands for the aryl hydrocarbon receptor—a cytosolic transcription factor responsive to toxic substances—facilitate the differentiation of T Helper 17 (Th17) cells, potentially exacerbating the autoinflammatory processes associated with SpA. Furthermore, smoking influences both the cellular and humoral aspects of the immune response, resulting in leukocytosis, impaired leukocyte functionality, and a decrease in various cytokines and soluble receptors, including interleukin (IL) 15, IL-1 receptor antagonist (IL-1Ra), IL-6, soluble IL-6 receptor (sIL-6R), as well as the vascular endothelial growth factor (VEGF) receptor. Studies have indicated that patients with SpA exhibit an increased prevalence of antibodies directed against a conserved epitope shared by the human leukocyte antigen B27 (HLA-B27)- and Klebsiella nitrogenase, in comparison to HLA-B27-positive controls. Additionally, current evidence regarding the GM suggests the presence of a gut–joint–skin axis, wherein the disruption of the mucosal barrier by specific bacterial species may enhance permeability to the gut-associated lymphoid tissue (GALT), resulting in localized inflammation mediated by Th1 and Th17 cells, as well as IL-17A. Finally, this review discusses the role of diet in shaping the microbial composition and its contribution to the pathogenesis of SpA. A comprehensive understanding of the mechanisms by which environmental factors influence the pathogenesis and progression of the disease could facilitate the development of novel personalized therapies targeting both external and internal environmental exposures, such as the gut microbial ecosystem. Full article

Alopecia areata (AA) is a complex autoimmune disorder with multifactorial pathogenesis. Recent research highlights the gut microbiota as a possible key player in AA pathogenesis through the gut–skin axis: gut dysbiosis may disrupt intestinal barrier integrity and immune tolerance by affecting T regulatory cells, potentially contributing to disease onset and progression. The purpose of this review is to analyze the current evidence on the correlation between gut microbiota and AA, dissecting both the pathogenetic role of its alterations in the onset and progression of disease and its potential role as a therapeutic target. Full article

Psoriatic arthritis (PsA) is a chronic inflammatory disease characterized by joint inflammation and skin lesions. Recent research has underscored the critical role of gut microbiota—comprising bacteria, fungi, viruses, and archaea—in the pathogenesis and progression of PsA. This narrative review synthesizes the latest findings on the influence of gut microbiota on PsA, focusing on mechanisms such as immune modulation, microbial dysbiosis, the gut-joint axis, and its impact on treatment. Advances in high-throughput sequencing and metagenomics have revealed distinct microbial profiles associated with PsA. Studies show that individuals with PsA have a unique gut microbiota composition, differing significantly from healthy controls. Alterations in the abundance of specific bacterial taxa, including a decrease in beneficial bacteria and an increase in potentially pathogenic microbes, contribute to systemic inflammation by affecting the intestinal barrier and promoting immune responses. This review explores the impact of various factors on gut microbiota composition, including age, hygiene, comorbidities, and medication use. Additionally, it highlights the role of diet, probiotics, and fecal microbiota transplantation as promising strategies to modulate gut microbiota and alleviate PsA symptoms. The gut-skin-joint axis concept illustrates how gut microbiota influences not only gastrointestinal health but also skin and joint inflammation. Understanding the complex interplay between gut microbiota and PsA could lead to novel, microbiome-based therapeutic approaches. These insights offer hope for improved patient outcomes through targeted manipulation of the gut microbiota, enhancing both diagnosis and treatment strategies for PsA. Full article

The COVID-19 pandemic has led to persistent complications beyond the respiratory system, with emerging evidence highlighting the role of gut dysbiosis in long COVID. Given the established gut–skin axis, alterations in gut microbiota post-COVID-19 may contribute to persistent dermatologic conditions such as eczema, acne, and rosacea. This review explores the mechanisms by which SARS-CoV-2 disrupts the gut microbiome, leading to systemic inflammation and skin disease. Furthermore, it examines potential interventions, including probiotics, prebiotics, and dietary modifications, as microbiome-targeted therapeutic strategies for post-COVID dermatologic recovery. Understanding this link may open new avenues for treating chronic inflammatory skin conditions in long COVID patients. Full article

Vitiligo is an autoimmune skin disease with a significant psychological burden and complex pathogenesis. While genetic factors contribute approximately 30% to its development, recent evidence suggests a crucial role of the gut microbiome in autoimmune diseases. This study investigated differences in gut microbiome composition and metabolic pathways between active spreading vitiligo patients and healthy controls using shotgun whole-genome sequencing in a Korean cohort. Taxonomic profiling reveals distinct characteristics in microbial community structure, with vitiligo patients showing an imbalanced proportion dominated by Actinomycetota and Bacteroidota. The vitiligo group exhibited significantly reduced abundance of specific species including Faecalibacterium prausnitzii, Faecalibacteriumduncaniae, and Meamonas funiformis, and increased Bifidobacterium bifidum compared to healthy controls. Metabolic pathway analysis identified significant enrichment in O-glycan biosynthesis pathways in vitiligo patients, while healthy controls showed enrichment in riboflavin metabolism and bacterial chemotaxis pathways. These findings provide new insights into the gut–skin axis in vitiligo pathogenesis and suggest potential therapeutic targets through microbiota modulation. Full article

Rosacea is a common inflammatory skin disease, characterized by erythema, papules and pustules. The pathophysiology of rosacea remains unclear, but the complex interplay between environmental and genetic factors may act as a trigger to an abnormal innate immune response associated with a multifaceted neurovascular reaction. Increasing evidence suggests that the gut microbiota is significantly involved in the pathogenesis of rosacea, playing an important role in the inflammatory cutaneous response. Dysbiosis, small intestinal bacterial overgrowth, Helicobacter pylori infection and innate immune system dysregulation mutually contribute to the pathophysiology of rosacea, but more extensive future research is needed to better clarify their precise mechanisms of action. Many dietary triggers have been postulated for this disease; however, there is a lack of well-made and controlled studies able to undoubtedly demonstrate a causal relationship between rosacea and diet. We analyzed the available studies on the role of diet and gut microbiome in rosacea and the positive clinical effects reported by the current literature on probiotics, prebiotics, postbiotics and nutrients. Ultimately, this article improves our understanding of the gut–skin axis in rosacea, focusing on how probiotic supplementation and diet could improve the clinical management of patients affected by this common and debilitating disease. Full article

Growing scientific evidence suggests a strong interconnection between inflammatory skin diseases and osteoporosis (OP), a systemic condition characterized by decreased bone density and structural fragility. These conditions seem to share common pathophysiological mechanisms, including immune dysregulation, chronic inflammation, and vitamin D deficiency, which play a crucial role in both skin and bone health. Additionally, the roles of gut microbiota (GM) and epigenetic regulation via microRNAs (miRNAs) emerge as key elements influencing the progression of both conditions. This review aims to examine the skin–bone axis, exploring how factors such as vitamin D, GM, and miRNAs interact in a subtle pathophysiological interplay driving skin inflammation and immune-metabolic bone alterations. Recent research suggests that combined therapeutic approaches—including vitamin D supplementation, targeted microbiota interventions, and miRNA-based therapies—could be promising strategies for managing comorbid inflammatory skin diseases and OP. This perspective highlights the need for multidisciplinary approaches in the clinical management of conditions related to the skin-bone axis. Full article

The ability of probiotics, comprising live microbiota, to modulate the composition of intestinal microbiomes has been connected to modulation of the central nervous system (Gut–Brain axis), neuroendocrine system (Gut–Skin axis), and immune response (Gut–Immune axis). Less information is known regarding the ability of postbiotics (cell wall components and secreted metabolites derived from live organisms) to regulate host immunity. In the present study, we tested postbiotics comprising single strains of bacteria and yeast (Lactobacillus acidophilus 16axg, Lacticaseibacillus rhamnosus 18fx, Saccharomyces cerevisiae var. boulardii 16mxg) as well as combinations of multiple strains for their ability to stimulate cytokine production by human CD14⁺ monocytes. We quantified cytokine gene and protein expression levels in monocytes following stimulation with postbiotics. Both heat-killed L. acidophilus and L. rhamnosus stimulated naïve monocytes without significant differences between them. Heat-killed S. boulardii stimulated less cytokine production compared to postbiotic bacteria at the same concentration. Interestingly, the addition of heat-killed yeast to heat-killed L. acidophilus and L. rhamnosus resulted in an enhancement of immune stimulation. Thus, heat-killed postbiotics have immune-modulating potential, particularly when bacteria and yeast are combined. This approach may hold promise for developing targeted interventions that can be fine-tuned to modulate host immune response with beneficial health impact. Full article

Atopic dermatitis (AD) is a chronic inflammatory skin condition with a high prevalence worldwide. AD pathogenesis is complex and consists of immune system dysregulation and impaired skin barrier, influenced by genetic and environmental factors. The purpose of the review is to show the complex interplay between atopic dermatitis and the microbiota. Human microbiota plays an important role in AD pathogenesis and the course of the disease. Dysbiosis is an important factor contributing to the development of atopic diseases, including atopic dermatitis. The gut microbiota can influence the composition of the skin microbiota, strengthening the skin barrier and regulating the immune response via the involvement of bacterial metabolites, particularly short-chain fatty acids, in signaling pathways of the gut–skin axis. AD can be modulated by antibiotic intake, dietary adjustments, hygiene, and living conditions. One of the promising strategies for modulating the course of AD is probiotics. This review offers a summary of how the microbiota influences the development and treatment of AD, highlighting aspects that warrant additional investigation. Full article

This study explores the relationship between dietary habits, environmental influences, and gut microbiome composition in individuals with hidradenitis suppurativa (HS), a chronic inflammatory skin condition. A cohort of 80 participants, equally divided into HS patients and healthy controls, was assessed through comprehensive questionnaires capturing demographics, dietary habits, and other health-related information. Fecal samples were collected and analyzed using next-generation sequencing to examine microbiome composition. Despite previous studies suggesting gut dysbiosis in HS, this research found no significant differences in alpha-diversity and Shannon diversity index between the groups. However, significant disparities in dietary habits were observed, with HS patients showing higher sugar and milk consumption. The study also identified a significant correlation between coffee consumption and the presence of certain bacterial genera. While the study did not reveal major differences in microbiome diversity, the findings on dietary habits and specific microbiome components suggest potential targets for therapeutic intervention. These results underscore the importance of further research into the gut–skin axis and its role in HS, aiming to enhance management strategies through dietary modifications and lifestyle interventions. Full article

The skin is a complex ecosystem colonized by millions of microorganisms, the skin microbiota, which are crucial in regulating not only the physiological functions of the skin but also the metabolic changes underlying the onset of skin diseases. The high microbial colonization together with a low diversity at the phylum level and a high diversity at the species level of the skin is very similar to that of the gastrointestinal tract. Moreover, there is an important communication pathway along the gut–brain–skin axis, especially associated with the modulation of neurotransmitters by the microbiota. Therefore, it is evident that the high complexity of the skin system, due not only to the genetics of the host but also to the interaction of the host with resident microbes and between microbe and microbe, requires a multi-omics approach to be deeply understood. Therefore, an integrated analysis, with high-throughput technologies, of the consequences of microbial interaction with the host through the study of gene expression (genomics and metagenomics), transcription (transcriptomics and meta-transcriptomics), and protein production (proteomics and meta-proteomics) and metabolite formation (metabolomics and lipidomics) would be useful. Although to date very few studies have integrated skin metabolomics data with at least one other ‘omics’ technology, in the future, this approach will be able to provide simple and fast tests that can be routinely applied in both clinical and cosmetic settings for the identification of numerous skin diseases and conditions. It will also be possible to create large archives of multi-omics data that can predict individual responses to pharmacological treatments and the efficacy of different cosmetic products on individual subjects by means of specific allotypes, with a view to increasingly tailor-made medicine. In this review, after analyzing the complexity of the skin ecosystem, we have highlighted the usefulness of this emerging integrated omics approach for the analysis of skin problems, starting with one of the latest ‘omics’ sciences, metabolomics, which can photograph the expression of the genome during its interaction with the environment. Full article

Background: Despite all the available treatments, psoriasis remains incurable; therefore, finding personalized therapies is a continuous challenge. Psoriasis is linked to a gut microbiota imbalance, highlighting the importance of the gut–skin axis and its inflammatory mediators. Restoring this imbalance can open new perspectives in psoriasis therapy. We investigated the effect of purified IgY raised against pathological human bacteria antibiotic-resistant in induced murine psoriatic dermatitis (PSO). Methods: To evaluate the immune portrayal in an imiquimod experimental model, before and after IgY treatment, xMAP array and flow cytometry were used. Results: There were significant changes in IL-1α,β, IL-5, IL-6, IL-9, IL-10, IL-12 (p70), IL-13, IL-15, IL-17a, IFN-γ, TNF-α, IP-10/CXCL10, MCP-1/CCL2, MIP-1α/CCL3, MIP-1β/CCL4, MIG/CXCL9, and KC/CXCL1 serum levels. T (CD3ε⁺), B (CD19⁺) and NK (NK1.1⁺) cells were also quantified. In our model, TNF-α, IL-6, and IL-1β cytokines and CXCL1 chemokine have extremely high circulatory levels in the PSO group. Upon experimental therapy, the cytokine serum values were not different between IgY-treated groups and spontaneously remitted PSO. Conclusions: Using the murine model of psoriatic dermatitis, we show that the orally purified IgY treatment can lead to an improvement in skin lesion healing along with the normalization of cellular and humoral immune parameters. Full article