Psoriasis and fatty liver: a harmful synergy

Intersecting Pathways: Nonalcoholic Fatty Liver Disease and Psoriasis Duet-A Comprehensive Review

Psoriasis is a chronic, immune-mediated, inflammatory disease that has a major impact on patients' quality of life. Common psoriasis-associated comorbidities include cardiovascular diseases, psoriatic arthritis, inflammatory bowel syndromes, type-2 diabetes, and metabolic syndrome. Nonalcoholic fatty liver disease (NAFLD) is affecting a substantial portion of the population and is closely linked with psoriasis. The interplay involves low-grade chronic inflammation, insulin resistance, and genetic factors. The review presents the pathophysiological connections between psoriasis and nonalcoholic fatty liver disease, emphasizing the role of cytokines, adipokines, and inflammatory cascades. The "hepato-dermal axis" is introduced, highlighting how psoriatic inflammation potentiates hepatic inflammation and vice versa. According to the new guidelines, the preliminary examination for individuals with psoriasis should encompass evaluations of transaminase levels and ultrasound scans as part of the initial assessment for this cohort. Considering the interplay, recent guidelines recommend screening for NAFLD in moderate-to-severe psoriasis cases. Treatment implications arise, particularly with medications impacting liver function. Understanding the intricate relationship between psoriasis and NAFLD provides valuable insights into shared pathogenetic mechanisms. This knowledge has significant clinical implications, guiding screening practices, treatment decisions, and the development of future therapeutic approaches for these chronic conditions.

The pan-liver network theory: From traditional chinese medicine to western medicine

In traditional Chinese medicine (TCM), the liver is the "general organ" that is responsible for governing/maintaining the free flow of qi over the entire body and storing blood. According to the classic five elements theory, zang-xiang theory, yin-yang theory, meridians and collaterals theory, and the five-viscera correlation theory, the liver has essential relationships with many extrahepatic organs or tissues, such as the mother-child relationships between the liver and the heart, and the yin-yang and exterior-interior relationships between the liver and the gallbladder. The influences of the liver to the extrahepatic organs or tissues have been well-established when treating the extrahepatic diseases from the perspective of modulating the liver by using the ancient classic prescriptions of TCM and the acupuncture and moxibustion. In modern medicine, as the largest solid organ in the human body, the liver has the typical functions of filtration and storage of blood; metabolism of carbohydrates, fats, proteins, hormones, and foreign chemicals; formation of bile; storage of vitamins and iron; and formation of coagulation factors. The liver also has essential endocrine function, and acts as an immunological organ due to containing the resident immune cells. In the perspective of modern human anatomy, physiology, and pathophysiology, the liver has the organ interactions with the extrahepatic organs or tissues, for example, the gut, pancreas, adipose, skeletal muscle, heart, lung, kidney, brain, spleen, eyes, skin, bone, and sexual organs, through the circulation (including hemodynamics, redox signals, hepatokines, metabolites, and the translocation of microbiota or its products, such as endotoxins), the neural signals, or other forms of pathogenic factors, under normal or diseases status. The organ interactions centered on the liver not only influence the homeostasis of these indicated organs or tissues, but also contribute to the pathogenesis of cardiometabolic diseases (including obesity, type 2 diabetes mellitus, metabolic [dysfunction]-associated fatty liver diseases, and cardio-cerebrovascular diseases), pulmonary diseases, hyperuricemia and gout, chronic kidney disease, and male and female sexual dysfunction. Therefore, based on TCM and modern medicine, the liver has the bidirectional interaction with the extrahepatic organ or tissue, and this established bidirectional interaction system may further interact with another one or more extrahepatic organs/tissues, thus depicting a complex "pan-hepatic network" model. The pan-hepatic network acts as one of the essential mechanisms of homeostasis and the pathogenesis of diseases.

Common Approach to Metabolic-Associated Fatty Liver Disease in Patients With Psoriasis: Consensus-Based Recommendations From a Multidisciplinary Group of Experts

Recent years have seen concerted efforts to understand the relation between psoriasis and metabolic-associated fatty liver disease (MAFLD). Not only is MALFD diagnosed more often in patients with psoriasis, but its clinical course is also more aggressive. A common approach is therefore needed to enable early detection of liver disease coincident with psoriasis. Especially important is an analysis of risks and benefits of potentially hepatotoxic treatments. This consensus paper presents the recommendations of a group of experts in dermatology and hepatology regarding screening for MALFD as well as criteria for monitoring patients and referring them to hepatologists when liver disease is suspected.

The Essential Role of IL-17 as the Pathogenetic Link between Psoriasis and Metabolic-Associated Fatty Liver Disease

Interleukin 17 (IL-17) is an effector cytokine that plays a key role in the pathogenesis of both psoriasis and metabolic-associated fatty liver disease (MAFLD), a condition that is more prevalent and severe in patients with psoriasis. In liver inflammation, IL-17 is mainly produced by CD4+ T (TH17) and CD8+ T cells (Tc17), although numerous other cells (macrophages, natural killer cells, neutrophils and Tγδ cells) also contribute to the production of IL-17. In hepatocytes, IL-17 mediates systemic inflammation and the recruitment of inflammatory cells to the liver, and it is also implicated in the development of fibrosis and insulin resistance. IL-17 levels have been correlated with progression from MAFLD to steatohepatitis, cirrhosis, and even hepatocellular carcinoma. Clinical trials have shown that inhibiting IL-17A in patients with psoriasis could potentially contribute to the improvement of metabolic and liver parameters. A better understanding of the key factors involved in the pathogenesis of these chronic inflammatory processes could potentially lead to more efficient treatment for both psoriasis and MAFLD, and help to develop holistic strategies to improve the management of these patients.

Risks of Biologic Therapy and the Importance of Multidisciplinary Approach for an Accurate Management of Patients with Moderate-Severe Psoriasis and Concomitant Diseases

Simple Summary

Psoriasis is a chronic multisystem inflammatory disease associated with a wide range of comorbidities including cardiovascular disease, hypertension, diabetes, hyperlipidemia, obesity, metabolic syndrome, anxiety, depression, chronic kidney disease, and malignancy. Currently available novel therapeutic options for moderate-severe psoriasis include tumor necrosis factor alpha inhibitors, inhibitors of the interleukin 17, and inhibitors of the interleukin 23. Apart from the concomitant diseases psoriasis patients may have, biologic therapy may cause significant complications requiring close collaboration between dermatologists and physicians of different specialties. Consequently, it was our main purpose to provide an overview of each class of biologic agents, as well as of the most frequent adverse events they may cause in psoriasis patients with concomitant diseases.

Abstract

Psoriasis is a chronic multisystem inflammatory disease associated with a plethora of comorbidities including metabolic syndrome, cardiovascular disease, hypertension, diabetes, hyperlipidemia, obesity, anxiety, depression, chronic kidney disease, and malignancy. Advancement in unveiling new key elements in the pathophysiology of psoriasis led to significant progress in the development of biologic agents which target different signaling pathways and cytokines involved in the inflammatory cascade responsible for the clinical manifestations found in psoriasis. Currently available novel therapeutic options for moderate-severe psoriasis include tumor necrosis factor alpha inhibitors, inhibitors of the interleukin 17, and inhibitors of the interleukin 23. Nevertheless, concerns have been raised with respect to the possible risks associated with the use of biologic therapy requiring close collaboration between dermatologists and physicians of different specialties. Our aim was to perform an in-depth literature review and discuss the potential risks associated with biologic therapy in patients with psoriasis and concurrent diseases with a focus on the influence of novel therapeutic agents on liver function in the context of hepatopathies, particularly viral hepatitis. A multidisciplinary teamwork and periodic evaluation of psoriasis patients under biologic therapy is highly encouraged to obtain an accurate management for each case.

Non-Alcoholic Fatty Liver Disease (NAFLD) in Patients with Psoriasis: A Review of the Hepatic Effects of Systemic Therapies

There is increasing interest in the association between psoriasis and non-alcoholic fatty liver disease (NAFLD), which is a prevalent liver disease characterized by excessive fat storage and inflammation that can progress to fibrosis and cancer. Patients with psoriasis have a two-fold higher risk to develop NAFLD and a higher risk to progress to more severe liver disease. Psoriasis and NAFLD share common risk factors such as smoking, alcohol consumption, and the presence of metabolic syndrome and its component disorders. In addition, both psoriasis and NAFLD hinge upon a systemic low-grade inflammation that can lead to a vicious cycle of progressive liver damage in NAFLD as well as worsening of the underlying psoriasis. Other important shared pathophysiological pathways include peripheral insulin resistance and oxidative stress. NAFLD should receive clinical awareness as important comorbidity in psoriasis. In this review, we assess the recent literature on the epidemiological and pathophysiological relationship of psoriasis and NAFLD, discuss the clinical implications of NAFLD in psoriasis patients, and summarize the hepatotoxic and hepatoprotective potential of systemic psoriasis therapies.

Analysis of Common Pathways and Markers From Non-Alcoholic Fatty Liver Disease to Immune-Mediated Diseases

Metabolic associated fatty liver disease (MAFLD) is the most prevalent form of liver disease worldwide, accounting for a high liver-related mortality and morbidity with extensive multi-organ involvement. This entity has displaced viral hepatitis as the main cause of severe forms of hepatic diseases, although the onset and transition of MAFLD stages still remains unclear. Nevertheless, innate and adaptive immune responses seem to play an essential role in the establishment and further progression of this disease. The immune system is responsible of safeguard and preserves organs and systems function, and might be altered under different stimuli. Thus, the liver suffers from metabolic and immune changes leading to different injuries and loss of function. It has been stablished that cell-cell crosstalk is a key process in the hepatic homeostasis maintenance. There is mounting evidence suggesting that MAFLD pathogenesis is determined by a complex interaction of environmental, genetic and host factors that leads to a full plethora of outcomes. Therefore, herein we will revisit and discuss the interplay between immune mechanisms and MAFLD, highlighting the potential role of immunological markers in an attempt to clarify its relationship.

Non-alcoholic fatty liver disease in patients with intestinal, pulmonary or skin diseases: Inflammatory cross-talk that needs a multidisciplinary approach

Non-alcoholic fatty liver disease (NAFLD) is currently considered the most common cause of liver disease. Its prevalence is increasing in parallel with the obesity and type 2 diabetes mellitus (DM2) epidemics in developed countries. Several recent studies have suggested that NAFLD may be the hepatic manifestation of a systemic inflammatory metabolic disease that also affects other organs, such as intestine, lungs, skin and vascular endothelium. It appears that local and systemic proinflammatory/anti-inflammatory cytokine imbalance, together with insulin resistance and changes in the intestinal microbiota, are pathogenic mechanisms shared by NAFLD and other comorbidities. NAFLD is more common in patients with extrahepatic diseases such as inflammatory bowel disease (IBD), obstructive syndrome apnea (OSA) and psoriasis than in the general population. Furthermore, there is evidence that this association has a negative impact on the severity of liver lesions. Specific risk characteristics for NAFLD have been identified in populations with IBD (i.e. age, obesity, DM2, previous bowel surgery, IBD evolution time, methotrexate treatment), OSA (i.e. obesity, DM2, OSA severity, increased transaminases) and psoriasis (i.e. age, metabolic factors, severe psoriasis, arthropathy, elevated transaminases, methotrexate treatment). These specific phenotypes might be used by gastroenterologists, pneumologists and dermatologists to create screening algorithms for NAFLD. Such algorithms should include non-invasive markers of fibrosis used in NAFLD to select subjects for referral to the hepatologist. Prospective, controlled studies in NAFLD patients with extrahepatic comorbidities are required to demonstrate a causal relationship and also that appropriate multidisciplinary management improves these patients’ prognosis and survival.

Psoriasis and Liver Damage in HIV-Infected Patients

Background/objectives: Psoriasis is the most frequent skin disease in HIV-infected patients. Nonalcohol fatty liver disease (NAFLD) is more prevalent in patients with psoriasis. We report the prevalence of psoriasis and NAFLD and investigate risk factors of liver damage in HIV-infected patients with psoriasis. Methods: We performed a retrospective observational study. Steatosis was defined as indicative abdominal ultrasound findings, CAP (controlled attenuated parameter by transient elastography) > 238 dB/m, and/or triglyceride and glucose index (TyG) > 8.38. Significant (fibrosis ≥ 2) and advanced liver fibrosis (fibrosis ≤ F3) were studied by transient elastography (TE) and/or FIB-4 using standard cutoff points. FIB-4 (Fibrosis 4 score) results were adjusted for hepatitis C (HCV)-coinfected patients. Results: We identified 80 patients with psoriasis (prevalence, 1.5%; 95% CI, 1.1–1.8). Psoriasis was severe (PASI > 10 and/or psoriatic arthritis) in 27.5% of cases. The prevalence of steatosis was 72.5% (95% CI, 65–85). Severe psoriasis was an independent risk factor for steatosis (OR, 12; 95% CI, 1.2–120; p = 0.03). Significant liver fibrosis (p < 0.05) was associated with HCV coinfection (OR 3.4; 95% CI, 1.1–10.6), total CD4 (OR 0.99; 95% CI, 0.99–1), and time of efavirenz exposure (OR 1.2; 95% CI, 1.0–1.3). Conclusions: The prevalence of psoriasis in HIV-infected patients was similar to that of the general population. Steatosis is highly prevalent, and severe psoriasis is an independent risk factor for steatosis in HIV-infected patients.

Research progress and perspective in metabolism and metabolomics of psoriasis

ABSTRACT

Psoriasis is considered a systemic disease associated with metabolic abnormalities, and it is important to understand the mechanisms by which metabolism affects pathophysiological processes both holistically and systematically. Metabolites are closely related to disease phenotypes, especially in systemic diseases under multifactorial modulation. The emergence of metabolomics has provided information regarding metabolite changes in lesions and circulation and deepened our understanding of the association between metabolic reprogramming and psoriasis. Metabolomics has great potential for the development of effective biomarkers for clinical diagnosis, therapeutic monitoring, prediction of the efficacy of psoriasis management, and further discovery of new metabolism-based therapeutic targets.

Establishment of Mouse Models of Psoriasis with Blood Stasis Syndrome Complicated with Glucose and Lipid Metabolism Disorders

Background

Psoriasis has been reported as a high-risk factor for quality of life and survival rate in patients with metabolic disorder. However, there is no animal model for studying this disease. This study aimed to establish and evaluate mouse models of psoriasis with blood stasis syndrome (which is a key to psoriasis pathogenesis, according to Chinese Medicine) complicated with metabolic disorders.

Method

Forty-five C57BL/6 mice were randomly divided into the blank control (Control), psoriasis (Imiquimod (IMQ)), psoriasis with metabolic disorders (IMQ + streptozotocin (STZ)), psoriasis with blood stasis syndrome (BSS) (IMQ + BSS), and psoriasis with blood stasis syndrome complicated with metabolic disorders (IMQ + STZ + BSS) groups (n = 9 mice/group). Psoriasis lesions were induced using IMQ cream (on both the ears and back, except in the Control group). Mice of the IMQ + BSS group were fed a half-fat, high-sugar diet and stimulated with ice-water swimming every day. Mice of the IMQ + STZ group were fed a half-fat, high-sugar diet and injected with STZ. Mice of the IMQ + STZ + BSS group were subjected to the same treatments as the IMQ + STZ and IMQ + BSS groups. After induction, the mice in each group were observed for vital signs, ear thickness, body weight, and psoriasis area and severity index (PASI) score. The mice were fasted for 12 h before determination of related laboratory serum indexes. Dorsal skin lesions, aortic arch pathology sections, and signal transducer and activator of transcription 3 (STAT3) were examined by H&E staining and immunohistochemistry.

Results

Laboratory indexes in the four model groups were significantly different from those in the Control group (p < 0.01); indicators of the IMQ + STZ, IMQ + BSS, and IMQ + STZ + BSS groups showed varying degrees of difference from those of the IMQ group.

Conclusions

The established mouse models of psoriasis blood stasis syndrome complicated with glucose and lipid metabolism disorders met the clinical and Chinese Medicine characteristics, and thus they could be used as animal models in future studies of psoriasis complicated with glucose and lipid metabolism disorders.