Potential Role of Probiotics in Ameliorating Psoriasis by Modulating Gut Microbiota in Imiquimod-Induced Psoriasis-Like Mice

Short-chain fatty acids ameliorate imiquimod-induced skin thickening and IL-17 levels and alter gut microbiota in mice: a metagenomic association analysis

Short-chain fatty acids (SCFAs) have been proposed to have anti-inflammatory effects and improve immune homeostasis. We aimed to examine the effects of SCFAs on skin phenotype, systemic inflammation, and gut microbiota in mice with psoriasis-like inflammation. Imiquimod (IMQ)-treated C57BL/6 mice served as the study model. We conducted a metagenomic association study of IMQ-mice treated with SCFAs or anti-IL-17 antibody using whole-genome shotgun sequencing. The associations among SCFA supplements, skin thickness, circulating inflammatory profiles, and fecal microbiota profiles were investigated. The microbiome study was performed using pipelines for phylogenetic analysis, functional gene analysis, and pathway analysis. In IMQ-treated mice, there were increases in skin thickness and splenic weight, as well as unique fecal microbial profiles. SCFAs ameliorated IMQ-induced skin thickening, splenic weight gain, and serum IL-17F levels, with results that were comparable with those receiving anti-IL-17 treatment. IMQ-treated mice receiving SCFAs had greater microbial diversity than mice treated with IMQ alone. SCFAs and anti-IL17 treatment were associated with alteration of gut microbiota, with increased prevalences of Oscillospiraceae and Lachnopiraceae and decreased prevalences of Muribaculaceae and Bacteroides, which have been predicted to be associated with increased glycan degradation, phenylalanine metabolism, and xylene degradation. SCFAs may mitigate IMQ-induced skin thickening and IL-17F levels and alter fecal microbiota profiles in IMQ-treated mice.

Effect of a topical traditional Chinese herbal medicine on skin microbiota in mouse model of atopic dermatitis

This study aims to explore the impact of the herbal ointment Chushi Zhiyang Ruangao (CSZYRG) on the skin's microecological environment in a mouse model of atopic dermatitis (AD) and to understand the underlying mechanisms involved. The AD model was established in C57 mice using calpolitol (a hypocalcemic analog of vitamin D3; MC903). Medication-free matrix ointment, CSZYRG, and mometasone furoate cream (positive control group) were applied to the injured areas. The skin lesions of AD model mice were photographed. Skin lesions were applied for the hematoxylin and eosin (H&E) staining to observe any pathological changes. Serum immunoglobulin IgE was detected by enzyme-linked immunosorbent assay (ELISA). The changes in the expression of inflammation-related factors TNF-α, IL-1β, and IL-6 in mice were detected using ELISA and qRT-PCR. Skin microflora samples were taken for 16S rDNA sequencing and analyzed for changes in the skin flora diversity, abundance, and dominant flora in mice. It was concluded that CSZYRG effectively alleviates skin lesions, serum IgE, and levels of TNF-α, IL-1β, and IL-6 in AD model mice. However, CSZYRG did not affect the skin microbial diversity of AD model mice but could exert an effect on the skin microbial community in AD mice and the relative abundance of the dominant microflora. CSZYRG may play a therapeutic role in AD by affecting the skin microbial community and relative abundance of dominant microflora in AD mice.

Atopic Dermatitis and Psoriasis: Similarities and Differences in Metabolism and Microbiome

Atopic dermatitis and psoriasis are common chronic inflammatory diseases of high incidence that share some clinical features, including symptoms of pruritus and pain, scaly lesions, and histologically, acanthosis and hyperkeratosis. Meanwhile, they are both commonly comorbid with metabolic disorders such as obesity and diabetes, indicating that both diseases may exist with significant metabolic disturbances. Metabolomics reveals that both atopic dermatitis and psoriasis have abnormalities in a variety of metabolites, including lipids, amino acids, and glucose. Meanwhile, recent studies have highlighted the importance of the microbiome and its metabolites in the pathogenesis of atopic dermatitis and psoriasis. Metabolic alterations and microbiome dysbiosis can also affect the immune, inflammatory, and epidermal barrier, thereby influencing the development of atopic dermatitis and psoriasis. Focusing on the metabolic and microbiome levels, this review is devoted to elaborating the similarities and differences between atopic dermatitis and psoriasis, thus providing insights into the intricate relationship between both conditions.

Efficacy of probiotic supplementation in the treatment of psoriasis-A systematic review and meta-analysis

OBJECTIVE

Many studies have emphasized the possible role of probiotics in psoriasis, probiotic supplementation might be helpful to treat psoriasis. This study systematically evaluated the efficacy of probiotic supplementation for the treatment of psoriasis.

METHODS

We searched some databases with keywords until November 10, 2023, including PubMed, Cochrane Library, Embase, and Web of Science. These keywords included probiotics, psoriasis RCT, and so on. After rigorous literature screening by two authors, five studies were identified. Eventually, the required data were independently extracted by another author.

RESULTS

A total of five studies with 286 patients were included. The pooled results showed that the efficacy of probiotic supplementation was superior to placebo in the treatment of psoriasis. The Psoriasis Area and Severity Index (SMD = -1.40, 95% Cl = -2.63 to -0.17, p < 0.00001) and Dermatology Life Quality Index (SMD = -0.92, 95% Cl = -1.86 to 0.01, p < 0.00001). Score decreased after probiotic supplementation.

CONCLUSIONS

The meta-analysis showed that probiotic supplementation could be a new treatment option for psoriasis.

Current research progress, opportunities, and challenges of Limosillactobacillus reuteri-based probiotic dietary strategies

Limosillactobacillus reuteri (L. reuteri), a type of Lactobacillus spp., stands out as the most extensively researched probiotic. Its remarkable intestinal adhesion has led to widespread applications in both the food and medical sectors. Notably, recent research highlights the probiotic efficacy of L. reuteri sourced from breast milk, particularly in influencing social behavior and mitigating atopic dermatitis. In this review, our emphasis is on surveying recent literature regarding the promotion of host's health by L. reuteri. We aim to provide a concise summary of the latest regulatory effects and potential mechanisms attributed to L. reuteri in the realms of metabolism, brain- and immune-related functions. The mechanism through which L. reuteri promotes host health by modulating the intestinal microenvironment primarily involves promoting intestinal epithelial renewal, bolstering intestinal barrier function, regulating gut microbiota and its metabolites, and suppressing inflammation and immune responses. Additionally, this review delves into new technologies, identifies shortcomings, and addresses challenges in current L. reuteri research. Finally, the application prospects of L. reuteri are provided. Therefore, a better understanding of the role and mechanisms of L. reuteri will contribute significantly to the development of new probiotic functional foods and enable precise, targeted interventions for various diseases.

Causal association of gut microbiota on spondyloarthritis and its subtypes: a Mendelian randomization analysis

Background

Despite establishing an association between gut microbiota and spondyloarthritis (SpA) subtypes, the causal relationship between them remains unclear.

Methods

Gut microbiota data were obtained from the MiBioGen collaboration, and SpA genome-wide association study (GWAS) summary data were obtained from the FinnGen collaboration. We conducted a two-sample Mendelian randomization (MR) analysis using the inverse-variance-weighted method supplemented with four additional MR methods (MR-Egger, weighted median, simple mode, and weighted mode). Pleiotropy and heterogeneity were also assessed. Reverse MR analysis was used to detect reverse causal relationships.

Results

We identified 23 causal links between specific gut microbiota taxa and SpA levels. Of these, 22 displayed nominal causal associations, and only one demonstrated a robust causal connection. Actinobacteria id.419 increased the risk of ankylosing spondylitis (AS) (odds ratio (OR) = 1.86 (95% confidence interval (CI): 1.29-2.69); p = 8.63E-04). The family Rikenellaceae id.967 was associated with a reduced risk of both AS (OR = 0.66 (95% CI: 0.47-0.93); p = 1.81E-02) and psoriatic arthritis (OR = 0.70 (95% CI: 0.50-0.97); p = 3.00E-02). Bacillales id.1674 increased the risk of AS (OR = 1.23 (95% CI: 1.00-1.51); p = 4.94E-02) and decreased the risk of enteropathic arthritis (OR = 0.56 (95% CI: 0.35-0.88); p = 1.14E-02). Directional pleiotropy, or heterogeneity, was not observed. No reverse causal associations were observed between the diseases and the gut microbiota.

Conclusion

Our MR analysis suggested a genetic-level causal relationship between specific gut microbiota and SpA, providing insights into the underlying mechanisms behind SpA development mediated by gut microbiota.

Bifidobacteria in disease: from head to toe

Bifidobacteria as a strictly anaerobic gram-positive bacteria, is widely distributed in the intestine, vagina and oral cavity, and is one of the first gut flora to colonize the early stages of life. Intestinal flora is closely related to health, and dysbiosis of intestinal flora, especially Bifidobacteria, has been found in a variety of diseases. Numerous studies have shown that in addition to maintaining intestinal homeostasis, Bifidobacteria may be involved in diseases covering all parts of the body, including the nervous system, respiratory system, genitourinary system and so on. This review collects evidence for the variation of Bifidobacteria in typical diseases among various systems, provides mild and effective therapeutic options for those diseases that are difficult to cure, and moves Bifidobacteria from basic research to further clinical applications.

Yogurt Alleviates Imiquimod-Induced Psoriasis by Activating the Lactate/GPR81 Signaling Axis in Mice

In addition to colorectal cancer and metabolic syndrome, regular yogurt consumption has shown promise in improving skin inflammation. In this study, we investigated the effects and possible mechanisms of yogurt on imiquimod-induced psoriasis-like inflammation in mice. After oral administration with yogurt (18 or 36 g/kg) and/or its main metabolite lactate (250 or 500 mg/kg) for 3 days, the mice were treated with a topical dose of 62.5 mg of imiquimod (IMQ) cream for seven consecutive days. Data showed that yogurt and lactate treatment significantly reduced the severity of psoriasis-like skin lesions, excessive keratinocyte proliferation, and immune cell infiltration. Mechanistically, we found that the genetic deficiency of the lactate receptor GPR81 aggravated psoriasis-like features in mice. Activation of the lactate/GPR81 axis inhibited the degradation of IκBα, prevented the nuclear translocation of histone deacetylase 3 (HDAC3) in macrophages, and thus constrained skin inflammation. Overall, these findings suggest that yogurt consumption effectively protects against experimental psoriasis and targeting the lactate/GPR81 signaling axis could be a promising approach for psoriasis inflammation management.

Metabolic influences on T cell in psoriasis: a literature review

Psoriasis is a systemic inflammatory disease that frequently coexists with various other conditions, such as essential hypertension, diabetes, metabolic syndrome, and inflammatory bowel disease. The association between these diseases may be attributed to shared inflammatory pathways and abnormal immunomodulatory mechanisms. Furthermore, metabolites also play a regulatory role in the function of different immune cells involved in psoriasis pathogenesis, particularly T lymphocytes. In this review, we have summarized the current research progress on T cell metabolism in psoriasis, encompassing the regulation of metabolites in glucose metabolism, lipid metabolism, amino acid metabolism, and other pathways within T cells affected by psoriasis. We will also explore the interaction and mechanism between psoriatic metabolites and immune cells. Moreover, we further discussed the research progress of metabolomics in psoriasis to gain a deeper understanding of its pathogenesis and identify potential new therapeutic targets through identification of metabolic biomarkers associated with this condition.

Immune Portrayal of a New Therapy Targeting Microbiota in an Animal Model of Psoriasis

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.

Targeting dysbiosis in psoriasis, atopic dermatitis, and hidradenitis suppurativa: the gut-skin axis and microbiome-directed therapy

Emerging evidence highlights the gut-skin microbiota as a potential therapeutic target for the management of inflammatory-driven cutaneous diseases as well as the interconnection of the gut-skin microbiota in disease pathogenesis and progression. Although not fully understood, recent research has indicated that commensal microbiota and the interaction of the gut-skin axis play an important role in maintaining skin homeostasis. Dysbiosis and disruption of the skin-gut microbiome may lead to impaired skin barrier function, thus triggering downstream inflammatory responses involved in the development of inflammatory skin disorders, especially in atopic dermatitis, psoriasis, and hidradenitis suppurativa. The skin microbiome may also serve as adjunctive therapeutic modalities for treatment. Herein, we review the latest reports on the interrelationship between microbial dysbiosis and inflammatory cutaneous diseases as well as emerging microbiome-directed therapeutics in atopic dermatitis, psoriasis, and hidradenitis suppurativa.

Impact of Gut Bacterial Metabolites on Psoriasis and Psoriatic Arthritis: Current Status and Future Perspectives

There is growing evidence that supports a role of gut dysbiosis in the pathogenesis of psoriasis (Pso). Thus, probiotic supplementation and fecal microbiota transplantation may serve as promising preventive and therapeutic strategies for patients with Pso. One of the basic mechanisms through which the gut microbiota interacts with the host is through bacteria-derived metabolites, usually intermediate or end products produced by microbial metabolism. In this study, we provide an up-to-date review of the most recent literature on microbial-derived metabolites and highlight their roles in the immune system, with a special focus on Pso and one of its most common comorbidities, psoriatic arthritis.

Efficacy and safety of biological agents to treat patients with palmoplantar pustulosis: A systematic scoping review

BACKGROUND

Palmoplantar pustulosis (PPP), a chronic, recurrent pustular dermatosis associated with erythema, scales, and sterile pustules on the palms and soles, is commonly encountered in dermatology clinics. Whether PPP is a variant of psoriasis or a distinct condition is still debated. Although biological agents have been successfully used to treat moderate-to-severe psoriasis, existing literature on PPP is limited to case reports or small case series. The lack of well-documented clinical studies makes it difficult to select the ideal treatment for this condition. This review aims to discuss the efficacy and safety of biological agents in PPP treatment based on randomized controlled trials with the hope of inspiring dermatologist clinicians to propose new therapeutic approaches.

OBJECTIVES

This review aims to obtain high-level evidence to assess the efficacy and safety of biological agents in the treatment of patients with PPP.

METHODS

We searched the PubMed, Embase, and Cochrane databases up to May 18, 2023, for high-quality randomized controlled trials that reported at least one adverse event after PPP treatment with biological agents in patients > 18 years of age. RevMan 5.3 software was used for the meta-analysis.

RESULTS

Nine trials involving 799 participants were included in the analysis. We used ppPASI 75 as the primary efficacy measure. Anti-IL-23 and anti-IL-17A agents afforded 4.14-fold and 1.95-fold better outcomes than placebo treatment at weeks 16 and 12, respectively (P-value = 0.009, RR = 4.14, 95% confidence interval [CI; 1.43-11.98]; P-value = 0.02, RR = 1.95, 95% CI [1.11-3.42]). Moreover, anti-IL-23 agents at a dose of 100 mg were more effective than at 200 mg, indicating that 100 mg may be the best dose for anti-IL-23 agents. Next, we investigated the safety of biological agents for PPP treatment. The incidence of total adverse events (AEs) was 1.25 times higher for biological agents than for controls, indicating a good safety profile (RR = 1.25, P-value ＜ 0.00001, 95% CI [1.13, 1.37]). Additionally, we divided the common AEs into 16 categories and found that anti-IL-23 agents were more likely to induce infections. In conclusion, we evaluated safety and efficacy in a comprehensive comparison and found that anti-IL-23 agents conferred good clinical efficacy with a low incidence of AEs and could be recommended with caution.

LIMITATIONS

Only a few relevant, high-quality, randomized controlled trials were included in the study.

CONCLUSION

This study showed that biological agents can be used to treat patients with PPP with good efficacy; however, AEs cannot be ignored. Multi-center, high-quality clinical studies with large sample sizes are needed to further evaluate the effects and safety of biological agents in PPP treatment.

A High-Fat, High-Cholesterol Diet Promotes Intestinal Inflammation by Exacerbating Gut Microbiome Dysbiosis and Bile Acid Disorders in Cholecystectomy

Patients with post-cholecystectomy (PC) often experience adverse gastrointestinal conditions, such as PC syndrome, colorectal cancer (CRC), and non-alcoholic fatty liver disease (NAFLD), that accumulate over time. An epidemiological survey further revealed that the risk of cholecystectomy is associated with high-fat and high-cholesterol (HFHC) dietary intake. Mounting evidence suggests that cholecystectomy is associated with disrupted gut microbial homeostasis and dysregulated bile acids (BAs) metabolism. However, the effect of an HFHC diet on gastrointestinal complications after cholecystectomy has not been elucidated. Here, we aimed to investigate the effect of an HFHC diet after cholecystectomy on the gut microbiota-BA metabolic axis and elucidate the association between this alteration and the development of intestinal inflammation. In this study, a mice cholecystectomy model was established, and the levels of IL-Iβ, TNF-α, and IL-6 in the colon were increased in mice fed an HFHC diet for 6 weeks. Analysis of fecal BA metabolism showed that an HFHC diet after cholecystectomy altered the rhythm of the BA metabolism by upregulating liver CPY7A1, CYP8B1, and BSEP and ileal ASBT mRNA expression levels, resulting in increased fecal BA levels. In addition, feeding an HFHC diet after cholecystectomy caused a significant dysbiosis of the gut microbiota, which was characterized by the enrichment of the metabolic microbiota involved in BAs; the abundance of pro-inflammatory gut microbiota and related pro-inflammatory metabolite levels was also significantly higher. In contrast, the abundance of major short-chain fatty acid (SCFA)-producing bacteria significantly decreased. Overall, our study suggests that an HFHC diet after cholecystectomy promotes intestinal inflammation by exacerbating the gut microbiome and BA metabolism dysbiosis in cholecystectomy. Our study also provides useful insights into the maintenance of intestinal health after cholecystectomy through dietary or probiotic intervention strategies.

Transforming Psoriasis Care: Probiotics and Prebiotics as Novel Therapeutic Approaches

Psoriasis is a chronic inflammatory skin disease with autoimmune pathological characteristics. Recent research has found a link between psoriasis, inflammation, and gut microbiota dysbiosis, and that probiotics and prebiotics provide benefits to patients. This 12-week open-label, single-center clinical trial evaluated the efficacy of probiotics (Bacillus indicus (HU36), Bacillus subtilis (HU58), Bacillus coagulans (SC208), Bacillus licheniformis (SL307), and Bacillus clausii (SC109)) and precision prebiotics (fructooligosaccharides, xylooligosaccharides, and galactooligosaccharides) in patients with psoriasis receiving topical therapy, with an emphasis on potential metabolic, immunological, and gut microbiota changes. In total, 63 patients were evaluated, with the first 42 enrolled patients assigned to the intervention group and the next 21 assigned to the control group (2:1 ratio; non-randomized). There were between-group differences in several patient characteristics at baseline, including age, psoriasis severity (the incidence of severe psoriasis was greater in the intervention group than in the control group), the presence of nail psoriasis, and psoriatic arthritis, though it is not clear whether or how these differences may have affected the study findings. Patients with psoriasis receiving anti-psoriatic local therapy and probiotic and prebiotic supplementation performed better in measures of disease activity, including Psoriasis Area and Severity Index, Dermatology Life Quality Index, inflammatory markers, and skin thickness compared with those not receiving supplementation. Furthermore, in the 15/42 patients in the intervention group who received gut microbiota analysis, the gut microbiota changed favorably following 12 weeks of probiotic and prebiotic supplementation, with a shift towards an anti-inflammatory profile.

Dose-Response Efficacy and Mechanisms of Orally Administered Bifidobacterium breve CCFM683 on IMQ-Induced Psoriasis in Mice

This study aimed to investigate the dose-response effect of Bifidobacterium breve CCFM683 on relieving psoriasis and its underlying patterns. Specifically, the expression of keratin 16, keratin 17, and involucrin were substantially decreased by administration of 10⁹ CFU and 10¹⁰ CFU per day. Moreover, interleukin (IL)-17 and TNF-α levels were substantially decreased by 10⁹ and 10¹⁰ CFU/day. Furthermore, the gut microbiota in mice treated with 10⁹ or 10¹⁰ CFU/day was rebalanced by improving the diversity, regulating microbe interactions, increasing Lachnoclostridium, and decreasing Oscillibacter. Moreover, the concentrations of colonic bile acids were positively correlated with the effectiveness of the strain in relieving psoriasis. The gavage dose should be more than 10^8.42 CFU/day to improve psoriasis according to the dose-effect curve. In conclusion, CCFM683 supplementation alleviated psoriasis in a dose-dependent manner by recovering microbiota, promoting bile acid production, regulating the FXR/NF-κB pathway, diminishing proinflammatory cytokines, regulating keratinocytes, and maintaining the epidermal barrier function. These results may help guide probiotic product development and clinical trials in psoriasis.

The Impact of Diet and Physical Activity on Psoriasis: A Narrative Review of the Current Evidence

Psoriasis is an inflammatory disease with strong genetic links and numerous features of autoimmunity that are also influenced by environment and lifestyle, including nutritional factors and physical activity (PA), with regards to the condition of patients. Recent reports in the field of nutrigenomics indicate a significant impact of nutrients in modulating microRNAs. However, few studies have evaluated the effect of nutritional systems and PA on treating psoriasis. This narrative review updates information regarding the current dietary recommendations for individuals with psoriasis and discusses the role of diet and PA in psoriasis prevention and treatment. Application of nutrigenetics in psoriasis therapy is also discussed. The PubMed and Google Scholar databases were searched using the MeSH terms for "nutrigenomics", "dietetics", "diet therapy", "diet", "physical activity", and "exercise" in conjunction with the MeSH terms for "psoriasis" and "dermatology". Evidence has shown that patients with psoriasis should have a personalized anti-inflammatory diet. Psoriasis patients are less physically active; most performed exercises of low-to-moderate intensity and were less likely to undertake regular exercise. Identifying nutrigenomic discoveries and the current lifestyle interventions associated with psoriasis can help physicians and physical therapists develop educational programs to manage and protect against the disease.

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.

Intestinal dysbiosis exacerbates the pathogenesis of psoriasis-like phenotype through changes in fatty acid metabolism

The intestinal microbiota has been associated with host immunity as well as psoriasis; however, the mechanism of intestinal microbiota regulating psoriasis needs to be demonstrated systematically. Here, we sought to examine its role and mechanism of action in the pathogenesis of psoriasis. We found that the severity of psoriasis-like skin phenotype was accompanied by changes in the composition of the intestinal microbiota. We performed co-housing and fecal microbial transplantation (FMT) experiments using the K14-VEGF transgenic mouse model of psoriasis and demonstrated that the transfer of intestinal microbiota from mice with severe psoriasis-like skin phenotype exacerbated psoriasiform skin inflammation in mice with mild symptoms, including increasing the infiltration and differentiation of Th17, and increased the abundance of Prevotella, while decreasing that of Parabacteroides distasonis, in the colon. These alterations affected fatty acid metabolism, increasing the abundance of oleic and stearic acids. Meanwhile, gentamicin treatment significantly reduced the abundance of Prevotella and alleviated the psoriasis-like symptoms in both K14-VEGF mice and imiquimod (IMQ)-induced psoriasis-like mice. Indeed, administration of oleic and stearic acids exacerbated psoriasis-like symptoms and increased Th17 and monocyte-derived dendritic cell infiltration in the skin lesion areas in vivo, as well as increased the secretion of IL-23 by stimulating DCs in vitro. At last, we found that, treatment of PDE-4 inhibitor alleviated psoriasis-like phenotype of K14-VEGF mice accompanied by the recovery of intestinal microbiota, including the decrease of Prevotella and increase of Parabacteroides distasonis. Overall, our findings reveal that the intestinal microbiota modulates host metabolism and psoriasis-like skin inflammation in mice, suggesting a new target for the clinical diagnosis and treatment of psoriasis.

Efficacy and safety of biological agents for the treatment of pediatric patients with psoriasis: A bayesian analysis of six high-quality randomized controlled trials

Background

Biological agents have been used with extreme caution in children because of their possible adverse effects.

Objectives

This study used high-quality randomized controlled trials (RCTs) to provide high-level evidence to assess the effectiveness and safety of biological agents for treating children with psoriasis.

Methods

We searched PubMed, Embase, Cochrane, and Web of Science databases through October 31, 2021. We included trials reporting at least one adverse event after treatment with biological agents of patients less than 18-year-old diagnosed with psoriasis. RevMan 5.3 and Stata 15.0 software were used for meta and Bayesian analyses.

Results

Six trials with 864 participants were included in the analysis. The results showed a 2.37-fold higher response rate in all biologics groups than in the control group for psoriasis area and severity index 75 (PASI75) (RR= 2.37, P-value < 0.01, 95% confidence interval [CI] [1.22, 4.62]). Compared with placebo, the PASI75 response rates of etanercept (RR= 2.82, 95% [CI] [1.10, 7.21]), ustekinumab low dose (RR= 7.45, 95%[CI] [1.25, 44.58]), and ustekinumab high dose (RR= 7.25, 95%[CI] [1.21, 43.41]) were superior. Additionally, the incidence of total adverse reactions was 1.05 times higher for biologics than for controls, indicating a good safety profile (RR= 1.05, P-value = 0.53, 95%[CI] [0.92, 1.19]). Overall, these six high-quality randomized controlled trials suggest that biologics are effective and safe for pediatric patients with psoriasis.

Limitations

Inclusion of few relevant, high-quality RCTs.

Conclusion

The results of this study indicate that biologics can be used to treat children with moderate-to-severe psoriasis without the risk of adverse effects. Ustekinumab showed the best efficacy and the fewest adverse effects.

Psoriasis: Interplay between dysbiosis and host immune system

With advancement in human microbiome research, an increasing number of scientific evidences have endorsed the key role of both gut and skin microbiota in the pathogenesis of psoriasis. Microbiome dysbiosis, characterized by altered diversity and composition, as well as rise of pathobionts, have been identified as possible triggers for recurrent episodes of psoriasis. Mechanistically, gut dysbiosis leads to "leaky gut syndrome" via disruption of epithelial bilayer, thereby, resulting in translocation of bacteria and other endotoxins to systemic circulation, which in turn, results in inflammatory response. Similarly, skin dysbiosis disrupts the cutaneous homeostasis, leading to invasion of bacteria and other pathogens to deeper layers of skin or even systemic circulation further enhanced by injury caused by pruritus-induced scratching, and elicit innate and adaptive inflammation. The present review explores the correlation of both skin and gut microbiota dysbiosis with psoriasis. Also, the studies highlighting the potential of bacteriotherapeutic approaches including probiotics, prebiotics, metabiotics, and fecal microbiota transplantation for the management of psoriasis have been discussed.

Gut Microbiota in Psoriasis

Psoriasis is a chronic inflammatory skin disease with autoimmune pathogenic characteristics and is caused by chronic inflammation, which results in uncontrolled keratinocyte growth and defective differentiation. The link between the gut microbiota and immune system regulation opened a novel angle to understand the pathogenesis of many chronic multifactorial diseases, including psoriasis. Current evidence suggests that modulation of the gut microbiota, both through dietary approaches and through supplementation with probiotics and prebiotics, could represent a novel therapeutic approach. The present work aims to highlight the latest scientific evidence regarding the microbiome alterations of psoriatic patients, as well as state of the art insights in terms of microbiome-targeted therapies as promising preventive and therapeutic tools for psoriasis.

The Role of Lifestyle and Nutrition in Psoriasis: Current Status of Knowledge and Interventions

Extrinsic environmental factors, including patient lifestyle (alcohol intake, smoking, stress, sleep disturbances, and sedentary habit), diet and single nutrients intake may affect psoriasis clinical presentation, severity, and course. All English language articles dealing with psoriasis and lifestyle factors or diet gathered by an extensive PubMed search were carefully examined in order to explore their impact on the disease. Current authoritative knowledge confirms that low‐calories, Mediterranean, and protein restricted/vegetarian diets may be beneficial. Psoriatic patients are also recommended to engage regular physical activity, to avoid alcohol intake and to consume fish rich in omega‐3 polyunsaturated fatty acids, as well as fruit and vegetables. Prebiotics and probiotics may also provide potential benefit, whereas vitamin D supplementation and gluten‐free diet are useful in selected cases only. Changing of dietary and lifestyle habits alone does not replace conventional treatment, but must be considered as an adjuvant. Physicians may play a crucial role, by adequately acknowledging psoriatic patients on the advantages of proper lifestyle and diet habits as well as providing clues to reliable sources of dietary advice.

Regulatory Effect of Lactiplantibacillus plantarum 2-33 on Intestinal Microbiota of Mice With Antibiotic-Associated Diarrhea

Diarrhea is one of the common adverse reactions in antibiotic treatment, which is usually caused by the imbalance of intestinal flora, and probiotics play an important role in the structure of intestinal flora. Therefore, this experiment studied the regulatory effect of Lactiplantibacillus plantarum 2-33 on antibiotic-associated diarrhea (AAD) mice. First, the AAD mice model was established by the mixed antibiotic solution of gentamicin sulfate and cefradine. Then, the physiological indexes and diarrhea of mice were observed and recorded by gastric perfusion of low dose (1.0 × 10⁷ CFU/ml), medium dose (1.0 × 10⁸CFU/ml), and high dose (1.0 × 10⁹ CFU/ml) strain 2-33. 16S rRNA gene V3-V4 regions were sequenced in colon contents of mice in control group, model group, self-healing group, and experimental group, respectively, and the diversity of intestinal flora and gene function prediction were analyzed. The results showed that the intestinal flora of AAD mice was not significantly regulated by gastric perfusion of strain 2-33 to 7 days, but the relative abundance and diversity of intestinal flora of AAD mice were significantly improved by gastric perfusion to 14 days (p < 0.05). In addition, at the genus level, the relative abundance of Lactobacillus increased significantly, and the relative abundance of Enterococcus and Bacillus decreased significantly (p < 0.05). In addition, the regulation of strain 2-33 on intestinal flora of AAD mice was time- and dose-dependent, short-term gastric perfusion, and low dose had no significant effect (p > 0.05). Strain 2-33 can significantly increase the levels of anti-inflammatory cytokines IL-4 and IL-10, significantly decrease the levels of proinflammatory cytokines TNF-α and IFN-γ (p < 0.05), and can also adjust carbohydrate metabolism, amino acid metabolism, and energy metabolism to normal levels, thus accelerating the recovery of intestinal flora structure of AAD mice. In summary, strain 2-33 can improve the structure and diversity of intestinal flora of AAD mice, balance the level of substance and energy metabolism, and play a positive role in relieving diarrhea, maintaining and improving the intestinal microecological balance.

Gut–Skin Axis: Unravelling the Connection between the Gut Microbiome and Psoriasis

Evidence has shown that gut microbiome plays a role in modulating the development of diseases beyond the gastrointestinal tract, including skin disorders such as psoriasis. The gut–skin axis refers to the bidirectional relationship between the gut microbiome and skin health. This is regulated through several mechanisms such as inflammatory mediators and the immune system. Dysregulation of microbiota has been seen in numerous inflammatory skin conditions such as atopic dermatitis, rosacea, and psoriasis. Understanding how gut microbiome are involved in regulating skin health may lead to development of novel therapies for these skin disorders through microbiome modulation, in particularly psoriasis. In this review, we will compare the microbiota between psoriasis patients and healthy control, explain the concept of gut–skin axis and the effects of gut dysbiosis on skin physiology. We will also review the current evidence on modulating gut microbiome using probiotics in psoriasis.

Microbiome Modulation as a Therapeutic Approach in Chronic Skin Diseases

There is a growing quantity of evidence on how skin and gut microbiome composition impacts the course of various dermatological diseases. The strategies involving the modulation of bacterial composition are increasingly in the focus of research attention. The aim of the present review was to analyze the literature available in PubMed (MEDLINE) and EMBASE databases on the topic of microbiome modulation in skin diseases. The effects and possible mechanisms of action of probiotics, prebiotics and synbiotics in dermatological conditions including atopic dermatitis (AD), psoriasis, chronic ulcers, seborrheic dermatitis, burns and acne were analyzed. Due to the very limited number of studies available regarding the topic of microbiome modulation in all skin diseases except for AD, the authors decided to also include case reports and original studies concerning oral administration and topical application of the pro-, pre- and synbiotics in the final analysis. The evaluated studies mostly reported significant health benefits to the patients or show promising results in animal or ex vivo studies. However, due to a limited amount of research and unambiguous results, the topic of microbiome modulation as a therapeutic approach in skin diseases still warrants further investigation.