Vitamin D status in Psoriasis: impact and clinical correlations

Exploring the polarization of M1 and M2 macrophages in the context of skin diseases

Macrophages are critical components of the immune system and play vital roles in pathogen defense, immune regulation, and tissue repair. These cells exhibit different polarization states depending on environmental signals, and the M1/M2 paradigm is a useful tool for comprehending these states. This review article comprehensively presents the underlying mechanisms of M1 and M2 macrophage polarization and examines their polarization in various skin diseases. Additionally, this paper discusses therapeutic strategies that target M1 and M2 macrophage polarization in skin diseases. A more profound understanding of macrophage polarization in skin diseases could provide valuable insights for the development of innovative therapeutic strategies.

Metabolic Disorders and Psoriasis: Exploring the Role of Nutritional Interventions

(1) Background: Psoriasis is a chronic autoimmune disease with a close relationship with metabolic diseases such as obesity, diabetes, and dyslipidemia. The aim of this review was to identify the relationship between psoriasis, metabolic diseases, and dietetic therapies. According to recent findings, there is a strong association between psoriasis and obesity as well as vitamin D and micronutrient deficiencies. (2) Methods: This review was conducted via PubMed, aiming to search for studies involving psoriasis linked with metabolic disorders or with nutritional treatments. (3) Results: Our review shows that a healthy lifestyle can positively influence the course of the disease. The maintaining of a proper body weight together with physical activity and good nutritional choices are associated with an improvement in psoriasis severity. A Mediterranean diet rich in fiber, vitamins, and polyphenols may indeed be a strategy for controlling psoriasis symptoms. The effectiveness of this diet lies not only in its anti-inflammatory power, but also in its ability to favorably influence the intestinal microbiota and counteract dysbiosis, which is a risk factor for many autoimmune diseases. (4) Conclusions: In synergy with standard therapy, the adoption of an appropriate diet can be recommended to improve the clinical expression of psoriasis and reduce the incidence of comorbidities.

Psoriasis and Vitamin D: A Systematic Review and Meta-Analysis

Psoriasis is a chronic immune-dysregulated inflammatory disease and hypovitaminosis D is considered a risk factor. We conducted an online database search to review and meta-analyze the relationship between vitamin D, other bone metabolism parameters, and psoriasis. The efficacy of oral vitamin D supplementation in improving Psoriasis Area and Severity Index (PASI) was also evaluated. Non-original articles, case reports, and animal studies were excluded. Bias risk was assessed according to the Cochrane Collaboration's tool and the Newcastle-Ottawa scale in randomized controlled trials (RCTs) and case-control studies, respectively. Unstandardized mean differences were used for data synthesis. Twenty-three studies reported serum 25 hydroxyvitamin D (25(OH)D) levels in 1876 psoriasis patients and 7532 controls. Psoriasis patients had significantly lower 25(OH)D levels than controls (21.0 ± 8.3 vs. 27.3 ± 9.8, p < 0.00001). Conversely, 450 psoriasis patients had lower levels of parathormone than 417 controls (38.7 ± 12.8 vs. 43.7 ± 16.5, p = 0.015). Four RCTs examined the effect of oral vitamin D supplementation on psoriasis for 173 patients and 160 patients were treated with placebo. No significant differences were found in PASI after 3, 6, and 12 months of supplementation. It is shown that 25(OH)D serum levels are significantly lower in psoriasis, but, although the granularity of RCT methodology may have influenced the pooled analysis, vitamin D supplementation did not seem to improve clinical manifestations.

Serum vitamin D levels can be predictive of psoriasis flares up after COVID-19 vaccination: a retrospective case control study

Introduction

Many patients with chronic inflammatory dermatosis such as psoriasis usually ask about the safety of COVID-19 vaccination and if it would affect the course of their disease. Indeed, many case reports, case series and clinical studies, reporting psoriasis exacerbation following vaccination against COVID-19, were published during the pandemic. Also, many questions arise regarding the existence of exacerbating factors of these flare ups, including environmental triggers such as the insufficiency of vitamin D levels.

Methods

This is a retrospective study that measures alterations in psoriasis activity and severity index (PASI) not exceeding 2 weeks after the first and second dose of COVID-19 vaccinations in the reported cases and assesses whether such changes have any association with patients' vitamin D levels. We retrospectively reviewed the case records of all patients with a documented flare up after COVID-19 vaccination in our department as well as those who did not, during a year.

Results

Among them, we found 40 psoriasis patients that had reported vitamin D levels in the form of 25-hydroxy-vitamin D within 3 weeks after vaccination, including 23 with exacerbation and 17 without exacerbation. Performing χ² and t-test controls for psoriasis patients with and without flare-ups, a statistically significant dependence emerged in the seasons of summer [χ²(1) = 5.507, p = 0.019], spring [χ²(1) = 11.429, p = 0.001] and in the categories of vitamin D [χ²(2) = 7.932, p = 0.019], while the mean value of vitamin D for psoriasis patients who did not have exacerbation (31.14 ± 6.67 ng/mL) is statistically higher [t(38) = 3.655, p = 0.001] than the corresponding value of psoriasis patients who had an exacerbation (23.43 ± 6.49 ng/mL).

Discussion

This study indicates that psoriasis patients with insufficient (21-29 ng/mL) or inadequate (<20 ng/mL) levels of vitamin D are more prone to postvaccination aggravation of the disease while vaccination in summer, a period with the most extent photo-exposition, can be a protective factor.