IL-17 May Be a Key Cytokine Linking Psoriasis and Hyperglycemia

Metabolic Syndrome and Psoriasis: Pivotal Roles of Chronic Inflammation and Gut Microbiota

In recent years, the incidence of metabolic syndrome (MS) has increased due to lifestyle-related factors in developed countries. MS represents a group of conditions that increase the risk of diabetes, cardiovascular diseases, and other severe health problems. Low-grade chronic inflammation is now considered one of the key aspects of MS and could be defined as a new cardiovascular risk factor. Indeed, an increase in visceral adipose tissue, typical of obesity, contributes to the development of an inflammatory state, which, in turn, induces the production of several proinflammatory cytokines responsible for insulin resistance. Psoriasis is a chronic relapsing inflammatory skin disease and is characterized by the increased release of pro-inflammatory cytokines, which can contribute to different pathological conditions within the spectrum of MS. A link between metabolic disorders and Psoriasis has emerged from evidence indicating that weight loss obtained through healthy diets and exercise was able to improve the clinical course and therapeutic response of Psoriasis in patients with obesity or overweight patients and even prevent its occurrence. A key factor in this balance is the gut microbiota; it is an extremely dynamic system, and this makes its manipulation through diet possible via probiotic, prebiotic, and symbiotic compounds. Given this, the gut microbiota represents an additional therapeutic target that can improve metabolism in different clinical conditions.

Effects of biological agents on glycogen metabolism in psoriasis patients: A systematic review and meta-analysis

The effectiveness and safety of biological agents for treating psoriasis have been confirmed; however, their effects on glucose metabolism biomarkers in psoriasis patients remain unclear. A systematic review and meta-analysis were performed according to PRISMA guidelines. The final analysis enrolled 12 studies, including eight randomized controlled trial (RCT) (n = 5628 patients) and four observational cohort studies (OBSs) (n = 393 patients). The meta-analysis comprising nine studies (six RCTs and three OBSs) revealed a slight reduction in the levels of HOMA-IR associated with the use of biological therapies in OBS (biological therapies vs. traditional therapies: WMD = -0.2, CI = -0.10 to 0.50, p = 0.02). Although a considerable number of studies were analysed, our review did not show a significant alteration in HOMA-IR levels among patients treated with biological therapies such as IL-17 inhibitors and IL-12/23 inhibitors at weeks 12-16 in RCTs. We also did not observe remarkable alterations in the fasting plasma glucose levels of patients in both OBS and RCT. Additional RCT on a larger scale and duration is required to provide more conclusive evidence regarding the effect of biological agents on glycogen metabolism in psoriasis.

Oral administration of punicalagin attenuates imiquimod-induced psoriasis by reducing ROS generation and inflammation via MAPK/ERK and NF-κB signaling pathways

Psoriasis, an immune-mediated chronic inflammatory skin disease, imposes a huge mental and physical burden on patients and severely affects their quality of life. Punicalagin (PU), the most abundant ellagitannin in pomegranates, has become a research hotspot owing to its diverse biological activities. However, its effects on psoriasis remain unclear. We explored the impact and molecular mechanism of PU on M5-stimulated keratinocyte cell lines and imiquimod (IMQ)-induced psoriasis-like skin inflammation in BABL/c mice using western blotting, quantitative real-time polymerase chain reaction (qRT-PCR), hematoxylin and eosin (H&E) stain, immunohistochemistry, and immunofluorescent. Administration of PU-enriched pomegranate extract at dosages of 150 and 250 mg/kg/day markedly attenuated psoriatic severity, abrogated splenomegaly, and reduced IMQ-induced abnormal epidermal proliferation, CD4+ T-cell infiltration, and inflammatory factor expression. Moreover, PU could decrease expression levels of pro-inflammatory cytokines, such as IL-1β, IL-1α, IL-6, IL-8, TNF-α, IL-17A, IL-22, IL-23A, and reactive oxygen species (ROS), followed by keratinocyte proliferation inhibition in the M5-stimulated cell line model of inflammation through inhibition of mitogen-activated protein kinases/extracellular regulated protein kinases (MAPK/ERK) and nuclear factor kappaB (NF-κB) signaling pathways. Our results indicate that PU may serve as a promising nutritional intervention for psoriasis by ameliorating cellular oxidative stress and inflammation.

IL-17A Orchestrates Reactive Oxygen Species/HIF1α-Mediated Metabolic Reprogramming in Psoriasis

Immune cell-derived IL-17A is one of the key pathogenic cytokines in psoriasis, an immunometabolic disorder. Although IL-17A is an established regulator of cutaneous immune cell biology, its functional and metabolic effects on nonimmune cells of the skin, particularly keratinocytes, have not been comprehensively explored. Using multiomics profiling and systems biology-based approaches, we systematically uncover significant roles for IL-17A in the metabolic reprogramming of human primary keratinocytes (HPKs). High-throughput liquid chromatography-tandem mass spectrometry and nuclear magnetic resonance spectroscopy revealed IL-17A-dependent regulation of multiple HPK proteins and metabolites of carbohydrate and lipid metabolism. Systems-level MitoCore modeling using flux-balance analysis identified IL-17A-mediated increases in HPK glycolysis, glutaminolysis, and lipid uptake, which were validated using biochemical cell-based assays and stable isotope-resolved metabolomics. IL-17A treatment triggered downstream mitochondrial reactive oxygen species and HIF1α expression and resultant HPK proliferation, consistent with the observed elevation of these downstream effectors in the epidermis of patients with psoriasis. Pharmacological inhibition of HIF1α or reactive oxygen species reversed IL-17A-mediated glycolysis, glutaminolysis, lipid uptake, and HPK hyperproliferation. These results identify keratinocytes as important target cells of IL-17A and reveal its involvement in multiple downstream metabolic reprogramming pathways in human skin.

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.

The Effects of Modified Intermittent Fasting in Psoriasis (MANGO): Protocol for a Two-Arm Pilot Randomized Controlled Open Cross-over Study

BACKGROUND

Psoriasis is a complex disease associated with multiple comorbidities, including metabolic syndrome and leaky gut syndrome. Dietary lifestyle interventions have been reported to affect the disease in terms of lesional severity. It remains unclear how diets affect these comorbidities and the general health in psoriasis patients. Modified intermittent fasting (MIF) on 2 nonconsecutive days has shown beneficial effects on metabolic parameters. A significant advantage of MIF over the currently investigated dietary changes is its feasibility.

OBJECTIVE

Here, we aim to study the effects of MIF on skin, gut, and metabolic health in psoriasis patients.

METHODS

A 2-arm pilot randomized controlled open cross-over study will be performed in 24 patients with psoriasis. Patients will be randomized 1:1 to either start with 12 weeks of MIF and go on a subsequent regular diet for another 12 weeks or start with 12 weeks of regular diet and do subsequent MIF for 12 weeks. The following parameters will be assessed: demographics, disease phenotype, medical and familial history, psoriasis severity, dermatology-specific and general quality of life, nutritional and physical habits, mental and intestinal health, intestinal and cutaneous integrity, inflammatory and metabolic markers, and satisfaction.

RESULTS

A total of 24 participants have been enrolled in the study. The final visit is foreseen for June 2021.

CONCLUSIONS

The aim is to uncover the effects of MIF on psoriasis severity and gut health integrity through clinical and molecular investigation. More precisely, we want to map the evolution of the different markers, such as psoriasis severity, permeability, and inflammation, in response to MIF as compared to a regular diet,. Understanding how dietary lifestyles can affect epithelial lineages, such as the skin and gut, will greatly improve our understanding of the development of psoriasis and may offer a nonpharmacological venue for treatments.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04418791; https://clinicaltrials.gov/ct2/show/NCT04418791.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/26405.

Metabolic Syndrome and Psoriasis: Mechanisms and Future Directions

Psoriasis is an immune-mediated systemic disease with associated comorbidities, including metabolic syndrome (MetS) which contributes substantially to premature mortality in patients with psoriasis. However, the pathological mechanisms underlying this comorbidity are unclear. Studies have shown that the pathological parameters of psoriasis mediate the development of MetS. We reviewed the potential mechanisms which mediate the association between psoriasis and MetS, including endoplasmic reticulum stress, pro-inflammatory cytokine releases, excess production of reactive oxygen species, alterations in adipocytokine levels and gut microbiota dysbiosis. Here, we highlight important research questions regarding this association and offer insights into MetS research and treatment.

Therapeutic wavelengths of ultraviolet B radiation activate apoptotic, circadian rhythm, redox signalling and key canonical pathways in psoriatic epidermis

Ultraviolet B radiation (UVB) exerts pleiotropic effects on human skin. DNA damage response and repair pathways are activated by UVB; if damage cannot be repaired, apoptosis ensues. Although cumulative UVB exposure predisposes to skin cancer, UVB phototherapy is widely used as an effective treatment for psoriasis. Previous studies defined the therapeutic action spectrum of UVB and showed that psoriasis is resistant to apoptosis. This study aimed to investigate early molecular responses within psoriasis plaques following irradiation with single equi-erythemogenic doses of clinically-effective (311 nm, narrow-band) compared to clinically-ineffective (290 nm) UVB. Forty-eight micro-dissected epidermal samples from 20 psoriatic patients were analyzed using microarrays. Our bioinformatic analysis compared gene expression between 311 nm irradiated, 290 nm irradiated and control psoriasis epidermis to specifically identify 311 nm UVB differentially expressed genes (DEGs) and their upstream regulatory pathways. Key DEGs and pathways were validated by immunohistochemical analysis. There was a dynamic induction and repression of 311 nm UVB DEGs between 6 h and 18 h, only a limited number of DEGs maintained their designated expression status between time-points. Key disease and function pathways included apoptosis, cell death, cell migration and leucocyte chemotaxis. DNA damage response pathways, NRF2-mediated oxidative stress response and P53 signalling were key nodes, interconnecting apoptosis and cell cycle arrest. Interferon signalling, dendritic cell maturation, granulocyte adhesion and atherosclerotic pathways were also differentially regulated. Consistent with these findings, top transcriptional regulators of 311 nm UVB DEGs related to: a) apoptosis, DNA damage response and cell cycle control; b) innate/acquired immune regulation and inflammation; c) hypoxia/redox response and angiogenesis; d) circadian rhythmicity; f) EGR/AP1 signalling and keratinocyte differentiation; and g) mitochondrial biogenesis. This research provides important insights into the molecular targets of 311 nm UVB, underscoring key roles for apoptosis and cell death. These and the other key pathways delineated may be central to the therapeutic effects of 311 nm in psoriasis.