Evaluating the efficacy of ursodeoxycholic acid plus methotrexate vs methotrexate alone in the treatment of moderate to severe plaque-type psoriasis: A randomized clinical trial

The Role of Bile Acid in Immune-Mediated Skin Diseases

Immune-mediated skin disorders arise from dysfunctional immune responses, instigating inflammatory dermatoses and a reduced quality of life. The complex pathogenesis likely involves genetic risks, environmental triggers and aberrant immune activation. An emerging body of evidence suggests that bile acid disturbances may critically promote immune pathology in certain skin conditions. Bile acids synthesised from cholesterol regulate nutrient metabolism and immune cell function via nuclear receptors and G protein-coupled receptors (GPCRs). Altered bile acid profiles and receptor expression have been identified in psoriasis, atopic dermatitis (AD) and autoimmune blistering diseases. Disruptions in bile acid signalling affect the inflammatory and metabolic pathways linked to these disorders. Targeting components of the bile acid axis represents a promising therapeutic strategy. This review elucidates the intricate links between bile acid homeostasis and immune dysfunction in inflammatory skin diseases, synthesising evidence that targeting bile acid pathways may unlock innovative therapeutic avenues. This study compiles clinical and experimental data revealing disrupted bile acid signalling and composition in various immune-mediated dermatoses, highlighting the emerging significance of bile acids in cutaneous immune regulation.

Analysis of factors influencing target PASI responses and side effects of methotrexate monotherapy in plaque psoriasis: a multicenter study of 1521 patients

Methotrexate (MTX) is commonly used as first-line systemic treatment agent in psoriasis. We aimed to evaluate the clinical characteristics and treatment responses of patients with psoriasis undergoing MTX monotherapy. Data from adult patients with plaque psoriasis who received MTX monotherapy for at least 3 months between April 2012 and April 2022 were retrospectively evaluated in 19 tertiary care centers. Our study included 722 female and 799 male patients, a total of 1521 participants. The average age of the patients was 44.3 ± 15.5 years. Mode of treatment was oral in 20.4% of patients while in 79.4% it was subcutaneous. The median treatment duration was 8 months (IQR = 5-15). The median weekly dose was 15 mg (IQR = 11-15). 1448 (95.2%) patients were taking folic acid supplementation. At week 12, 16.3% of the patients achieved PASI (Psoriasis Area and Severity Index) 90 response while at week 24, 37.3% achieved it. Logistic regression analysis for week 12 identified the following independent factors affecting PASI 90 achievement positively: median weekly MTX dose ≤ 15 mg (P = 0.011), subcutaneous administration (P = 0.005), no prior systemic treatment (< 0.001) and folic acid use (0.021). In logistic regression analysis for week 24; median weekly MTX dose ≤ 15 mg (P = 0.001), baseline PASI ≥ 10 (P < 0.001), no prior systemic treatment (P < 0.004), folic acid use (P = 0.001) and absence of comorbidities (P = 0.009) were determined as independent factors affecting the achievement of PASI 90. Adverse effects were observed in 38.8% of the patients, with nausea/vomiting (23.9%) and transaminase elevation (13%) being the most common. The most common reasons for interruptions (15.3%) and discontinuations (27.1%) of the treatment were patient related individual factors. The use of MTX as the first systemic treatment agent, at doses ≤ 15 mg/week and concurrent folic acid application are positive predictive factors for achieving the target PASI response both at weeks 12 and 24. In our study, which is one of the most comprehensive studies on MTX treatment in psoriasis, we observed that MTX is an effective and safe treatment option.

Primary biliary cirrhosis and psoriasis: a two-sample Mendelian randomization study

Background

Primary biliary cirrhosis (PBC) and psoriasis are frequently observed to co-occur in clinical settings. However, the causal associations and underlying mechanisms between PBC and psoriasis remain poorly defined.

Methods

In this study, we conducted bidirectional MR analysis to explore the causal relationship between PBC and psoriasis using four MR methods: inverse-variance weighted, MR-Egger regression, weighted median, and weighted mode. Sensitivity analyses were carried out, employing different models and testing methods for comparison to assess the influence of heterogeneity and pleiotropy on our findings and to confirm the robustness of these results.

Results

A causal relationship between the risk of PBC and psoriasis was identified, as confirmed by IVW analysis (OR: 1.081, 95%CI: 1.028~1.137, P<0.05). The other three MR methods also produced similar results. However, psoriasis did not have a causal effect on PBC risk (OR: 1.022, 95%CI: 0.935~1.118, P>0.05). The intercept of MR-Egger regression was 0.0013 (P>0.05), indicating that genetic pleiotropy did not influence the results. Additionally, the leave-one-out analysis demonstrated the robustness of our MR findings.

Conclusion

This study reveals a causal relationship between PBC and psoriasis, with PBC increasing the risk of psoriasis, but not the reverse. This potential causal relationship offers a new perspective on the etiology of PBC.

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.

The Emerging Potential of Bile Acids as a Modulator of Psoriatic Inflammation

Background

Bile acids (BAs) are cholesterol-based amphipathic surfactants that are most widely known for their contributions to lipid metabolism, but more recently have been increasingly recognized as a key signaling molecule in inflammatory diseases as well as, potentially, psoriatic disease.

Objective

This brief review reviews relevant literature in order to briefly describe the synthesis of bile acids and their subsequent metabolism and to analyze recent animal and human data that supports anti-inflammatory activity of some BAs in psoriasiform dermatitis.

Methods

Pubmed and other public sources were used to survey the literature relevant to the topic of bile acids and their potential use in psoriasis.

Conclusion

There is clinical and preclinical evidence to support a potential role for BA Supplementation (or modulation BA metabolism and signaling) in the treatment of psoriasis.

Methotrexate Dosing Regimen for Plaque-type Psoriasis: An Update of a Systematic Review

Background Methotrexate (MTX) is a systemic treatment for plaque-type psoriasis. At the time of approval, no dose-ranging studies were performed. Nowadays, a uniform dosing regimen is lacking. This might contribute to suboptimal treatment with the drug.Objective To summarize the literature involving the MTX dosing regimens in psoriasis patients.Methods In this SR, RCTs and documents with aggregated evidence (AgEv) on the MTX dosing regimen in psoriasis were summarized. All randomized controlled trials (RCTs) in which oral, subcutaneous or intramuscular MTX was used in patients with psoriasis and AgEv, were included. The MEDLINE, EMBASE and CENTRAL databases were searched up to June 20, 2022. This SR was registered in PROSPERO.Results Thirty-nine RCTs had a high risk of bias. Test dosages were given in only 3 RCTs. In the RCTs, MTX was usually prescribed in a start dose of 7.5 mg/week (n = 13). MTX was mostly given in a start dose of 15 mg/week, in the AgEv (n = 5). One guideline recommended a test dose, in other aggregated evidence a test dose was not mentioned or even discouraged.Conclusions There is a lack of high-quality evidence and available data for dosing MTX in psoriasis is heterogeneous.