Lack of effect of the glucagon-like peptide-1 receptor agonist liraglutide on psoriasis in glucose-tolerant patients--a randomized placebo-controlled trial

The Regulation of Metabolic Homeostasis by Incretins and the Metabolic Hormones Produced by Pancreatic Islets

In healthy humans, the complex biochemical interplay between organs maintains metabolic homeostasis and pathological alterations in this process result in impaired metabolic homeostasis, causing metabolic diseases such as diabetes and obesity, which are major global healthcare burdens. The great advancements made during the last century in understanding both metabolic disease phenotypes and the regulation of metabolic homeostasis in healthy individuals have yielded new therapeutic options for diseases like type 2 diabetes (T2D). However, it is unlikely that highly desirable more efficacious treatments will be developed for metabolic disorders until the complex systemic regulation of metabolic homeostasis becomes more intricately understood. Hormones produced by pancreatic islet beta-cells (insulin) and alpha-cells (glucagon) are pivotal for maintaining metabolic homeostasis; the activity of insulin and glucagon are reciprocally correlated to achieve strict control of glucose levels (normoglycaemia). Metabolic hormones produced by other pancreatic islet cells and incretins produced by the gut are also crucial for maintaining metabolic homeostasis. Recent studies highlighted the incomplete understanding of metabolic hormonal synergism and, therefore, further elucidation of this will likely lead to more efficacious treatments for diseases such as T2D. The objective of this review is to summarise the systemic actions of the incretins and the metabolic hormones produced by the pancreatic islets and their interactions with their respective receptors.

A systematic review of 454 randomized controlled trials using the Dermatology Life Quality Index: experience in 69 diseases and 43 countries

BACKGROUND

Over 29 years of clinical application, the Dermatology Life Quality Index (DLQI) has remained the most used patient-reported outcome (PRO) in dermatology due to its robustness, simplicity and ease of use.

OBJECTIVES

To generate further evidence of the DLQI's utility in randomized controlled trials (RCTs) and to cover all diseases and interventions.

METHODS

The methodology followed PRISMA guidelines and included seven bibliographical databases, searching articles published from 1 January 1994 until 16 November 2021. Articles were reviewed independently by two assessors, and an adjudicator resolved any opinion differences.

RESULTS

Of 3220 screened publications, 454 articles meeting the eligibility criteria for inclusion, describing research on 198 190 patients, were analysed. DLQI scores were primary endpoints in 24 (5.3%) of studies. Most studies were of psoriasis (54.1%), although 69 different diseases were studied. Most study drugs were systemic (85.1%), with biologics comprising 55.9% of all pharmacological interventions. Topical treatments comprised 17.0% of total pharmacological interventions. Nonpharmacological interventions, mainly laser therapy and ultraviolet radiation treatment, comprised 12.2% of the total number of interventions. The majority of studies (63.7%) were multicentric, with trials conducted in at least 42 different countries; 40.2% were conducted in multiple countries. The minimal clinically importance difference (MCID) was reported in the analysis of 15.0% of studies, but only 1.3% considered full score meaning banding of the DLQI. Forty-seven (10.4%) of the studies investigated statistical correlation of the DLQI with clinical severity assessment or other PRO/quality of life tools; and 61-86% of studies had within-group scores differences greater than the MCID in 'active treatment arms'. The Jadad risk-of-bias scale showed that bias was generally low, as 91.8% of the studies had Jadad scores of ≥ 3; only 0.4% of studies showed a high risk of bias from randomization. Thirteen per cent had a high risk of bias from blinding and 10.1% had a high risk of bias from unknown outcomes of all participants in the studies. In 18.5% of the studies the authors declared that they followed an intention-to-treat protocol; imputation for missing DLQI data was used in 34.4% of studies.

CONCLUSIONS

This systematic review provides a wealth of evidence of the use of the DLQI in clinical trials to inform researchers' and -clinicians' decisions for its further use. Recommendations are also made for improving the reporting of data from future RCTs using the DLQI.

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.

[Translated article] Glucagon-Like Peptide-1 Agonists for Treating Obesity in Patients With Immune-Mediated Skin Diseases

Psoriasis and hidradenitis suppurativa are often associated with obesity. Because chronic low-grade inflammation underlies these 2 diseases, they can progress to more severe forms in patients with obesity if weight-reduction measures are not taken. This review covers pharmacologic alternatives for treating obesity, with emphasis on the benefits associated with the novel use of glucagon-like peptide-1 (GLP-1) agonists that act on satiety receptors. These drugs have led to greater weight loss in clinical trials and real-world settings than orlistat, which until recently was the only drug approved for treating obesity in the European Union. Although experience with GLP-1 agonists in patients with obesity and inflammatory skin diseases is currently scarce, the promising results reported suggest they may offer a useful tool for managing obesity.

Glucagon-Like Peptide 1 Receptor Agonists in Patients With Inflammatory Arthritis or Psoriasis: A Scoping Review

ABSTRACT

Obesity is a proinflammatory state associated with increased disease severity in various types of inflammatory arthritis. Weight loss is associated with improved disease activity in certain forms of inflammatory arthritis such as rheumatoid arthritis (RA) and psoriatic arthritis (PsA). We conducted a scoping review summarizing the literature evaluating the effect of glucagon-like peptide 1 (GLP-1) receptor agonists on weight and disease activity in patients with inflammatory arthritis or psoriasis. MEDLINE, PubMed, Scopus, and Embase were searched for publications evaluating the role of GLP-1 analogs in RA, PsA, psoriasis, axial spondyloarthritis, systemic lupus erythematosus, systemic sclerosis, gout, and calcium pyrophosphate deposition disease. Nineteen studies were included: 1 gout study, 5 RA studies (3 basic science, 1 case report, and 1 longitudinal cohort), and 13 psoriasis studies (2 basic science, 4 case reports, 2 combined basic science/clinical studies, 3 longitudinal cohorts, and 2 randomized controlled trials). No psoriasis study reported on PsA outcomes. Basic science experiments demonstrated weight-independent immunomodulatory effects of GLP-1 analogs through inhibition of the NF-κB pathway (via AMP-activated protein kinase phosphorylation in psoriasis and prevention of IκBα phosphorylation in RA). In RA, improved disease activity was reported. In psoriasis, 4 of 5 clinical studies demonstrated significant improvements in Psoriasis Area Severity Index and weight/body mass index with no major adverse events. Common limitations included small sample sizes, short follow-up periods, and lack of control groups. GLP-1 analogs safely cause weight loss and have potential weight-independent anti-inflammatory effects. Their role as an adjunct in patients with inflammatory arthritis and obesity or diabetes is understudied, warranting future research.

Glucagon-Like Peptide-1 Agonists for Treating Obesity in Patients With Immune-Mediated Skin Diseases

Psoriasis and hidradenitis suppurativa are often associated with obesity. Because chronic low-grade inflammation underlies these 2 diseases, they can progress to more severe forms in patients with obesity if weight-reduction measures are not taken. This review covers pharmacologic alternatives for treating obesity, with emphasis on the benefits associated with the novel use of glucagon-like peptide-1 (GLP-1) agonists that act on satiety receptors. These drugs have led to greater weight loss in clinical trials and real-world settings than orlistat, which until recently was the only drug approved for treating obesity in the European Union. Although experience with GLP-1 agonists in patients with obesity and inflammatory skin diseases is currently scarce, the promising results reported suggest they may offer a useful tool for managing obesity.

Molecular Background and Clinical Implications of Glucose Disorders in Patients with Psoriatic Arthritis

Psoriatic arthritis (PsA) is an inflammatory musculoskeletal disease characterized by joint and entheses involvement. This condition is often associated with an increased prevalence of obesity, encompassing more than one-third of all patients. Given the presence of metabolic disorders, it becomes crucial to enhance clinical oversight of metabolic parameters. An early diagnosis of glucose irregularities in PsA allows for the assessment of an effective treatment strategy. The approach proves valuable in preventing the development of insulin resistance (IR) or diabetes mellitus type 2 (DMt2). Similar pathways characterize the pathomechanism of PsA and DMt2, offering an innovative perspective on treatment management. The cytokines and adipokines synthesized in the course of PsA significantly impact the development process of IR and DMt2 in different mechanisms of action. Conversely, glucose disorders influence the activity of PsA and therapy outcomes. Given the chronic inflammatory background shared by PsA, obesity, and DMt2, it is evident that inadequate management of any of the mentioned conditions can exacerbate the others. Thus, when PsA coincides with DMt2, a comprehensive multidimensional approach is necessary. This includes an effective immunosuppressive regimen complemented by appropriate anti-diabetic and insulin therapies. Moreover, often overlooked recommendations concerning overall well-being and lifestyle adjustments hold significance. This manuscript explores the connections and the relationship between the molecular background of PsA and glucose disorders. It provides a detailed exposition of specific therapeutic approaches for both conditions.

The Weight-loss Effect of GLP-1RAs Glucagon-Like Peptide-1 Receptor Agonists in Non-diabetic Individuals with Overweight or Obesity: A Systematic Review with Meta-Analysis and Trial Sequential Analysis of Randomized Controlled Trials

BACKGROUND

Glucagon-like peptide-1 receptor agonists (GLP-1RAs) are new drugs for the treatment of obesity.

OBJECTIVE

To assess the weight-loss effects of GLP-1RAs in the treatment of patients with overweight or obesity without diabetes.

METHODS

This is a systematic review with meta-analysis and trial sequential analysis. PubMed, Embase, and Cochrane Central Register of Controlled Trials were searched from their inception to January 1, 2022. Eligible trials report on outcomes including body weight (BW), body mass index (BMI), waist circumference (WC), waist-to-hip ratio (WHR), or total body fat (TBF). Mean differences (MDs) and standardized mean differences (SMDs) were summarized using random-effects models.

RESULTS

Forty-one trials involving 15,135 participants were included. Compared with controls, GLP-1RAs significantly reduced BW (MD -5.319 kg, 95% CI: -6.465, -4.174), BMI (MD -2.373 kg/m2, 95% CI: -2.821, -1.924), WC (MD -4.302 cm, CI:-5.185 to -3.419), WHR (MD -0.011, CI -0.015 to -0.007), but not TBF (MD -0.320%, CI -1.420 to -0.780). Trial sequential analysis (TSA) supported conclusive evidence of the effects of GLP-1RAs on BW, BMI, and WC for weight loss. GLP-1RAs had nonlinear dose-response relationships with weight loss. Extensive sensitivity analyses demonstrated the robustness of the results, though the GRADE certainty of the evidence ranged from high to very low. High to moderate GRADE certainty of evidence suggested semaglutide as the most effective GLP-1RA agent, with the best efficacy and low to moderate risk of adverse effects.

CONCLUSIONS

The present study provides conclusive evidence for the effect of GLP-1RAs on weight loss in a nonlinear dose-response manner in patients with obesity or overweight without diabetes. In terms of changes in BW, BMI, and WC, there is firm evidence for the overall weight-loss effects of GLP-1RAs. Of the GLP-1RAs, semaglutide might be the most effective agent.

Effects of Hypolipidemic Drugs on Psoriasis

Psoriasis is a chronic, systematic, inflammatory disease in which multiple metabolic and immunologic disturbances lead to lipid abnormalities, impaired glucose tolerance, metabolic syndrome, diabetes mellitus, atherosclerosis, hypertension, ischemic heart disease, and numerous metabolic disorders. In clinical practice, the most commonly used drugs in the treatment of lipid abnormalities are statins and fibrates. Statins are characterized by pleiotropic effects such as antioxidant, anti-inflammatory, anticoagulant, and antiproliferative. They work by reducing the concentrations of low-density lipoprotein (LDL), total cholesterol, and triglycerides and stabilizing atherosclerotic plaque. Fibrates are medications, which help to lower triglycerides, LDL, very low-density lipoprotein (VLDL) levels and increase lower high-density lipoprotein (HDL). In recent years, many new drugs were found to normalize the lipid profile in patients with psoriasis: glitazones (pioglitazone, troglitazone), and glucagon-like peptide-1 (GLP-1) receptor agonists. Pioglitazone improves the lipid profile, including the decrease of triglycerides, fatty acids, and LDL, as well as the increase of HDL. Glucagon-like peptide 1 (GLP-1) analogs decrease modestly low-density lipoprotein cholesterol (LDL-C), total cholesterol, and triglycerides. The purpose of this study is to assess the current state of knowledge on the effect of different hypolipidemic treatments on the course of psoriasis. The study includes literature from medical databases PubMed and Google Scholar. We were browsing PubMed and Google Scholar until the beginning of December. The systematic review includes 41 eligible original articles.

The Antiobesity Effect and Safety of GLP-1 Receptor Agonist in Overweight/Obese Patients Without Diabetes: A Systematic Review and Meta-Analysis

Aim To determine the antiobesity effect and safety of glucagon-like peptide-1 receptor agonist (GLP-1RA) including liraglutide, exenatide and semaglutide treatment in overweight/obese patients without diabetes. The random-effect model was used to pool data extracted from included literatures. The weighted mean difference (WMD), odds ratio and 95% confidence interval (CI) were used to present the meta-analysis results (PROSPERO registration number: CRD 42020173199). The sources of intertrial heterogeneity, bias and the robustness of results were evaluated by subgroup analysis, sensitivity analysis and regression analysis, respectively. A total of 24 RCTs were recruited in the present analysis which included 5867 patients. The results showed that the treatment of overweight/obese patients without diabetes with GLP-1RAs including liraglutide, exenatide and semaglutide significantly achieved greater weight loss than placebo [WMD=-5.39, 95% CI (-6.82, -3.96)] and metformin [WMD=-5.46, 95% CI (-5.87, -5.05)]. The subgroup analysis showed that semaglutide displayed the most obvious antiobesity effect in terms of weight loss, the reduction of body mass index (BMI) and waist circumference (WC). However, GLP-1RAs treatments had more gastrointestinal adverse events (such as nausea and vomiting) than placebo and Met. The subgroup analysis also represented that semaglutide displayed the lowest risk of gastrointestinal adverse events among three kinds of GLP-1RAs. Our meta-analysis demonstrated that GLP-1RA had a superior antiobesity effect than placebo/Met in overweight/obese patients without diabetes in terms of body weight, BMI, and WC, especially for semaglutide, which had more obvious antiobesity effect and lower GI adverse events than liraglutide and exenatide.

GLP-1a: Going beyond Traditional Use

Glucagon-like peptide-1 (GLP-1) is a human incretin hormone derived from the proglucagon molecule. GLP-1 receptor agonists are frequently used to treat type 2 diabetes mellitus and obesity. However, the hormone affects the liver, pancreas, brain, fat cells, heart, and gastrointestinal tract. The objective of this study was to perform a systematic review on the use of GLP-1 other than in treating diabetes. PubMed, Cochrane, and Embase were searched, and the PRISMA guidelines were followed. Nineteen clinical studies were selected. The results showed that GLP-1 agonists can benefit defined off-medication motor scores in Parkinson’s Disease and improve emotional well-being. In Alzheimer’s disease, GLP-1 analogs can improve the brain’s glucose metabolism by improving glucose transport across the blood–brain barrier. In depression, the analogs can improve quality of life and depression scales. GLP-1 analogs can also have a role in treating chemical dependency, inhibiting dopaminergic release in the brain’s reward centers, decreasing withdrawal effects and relapses. These medications can also improve lipotoxicity by reducing visceral adiposity and decreasing liver fat deposition, reducing insulin resistance and the development of non-alcoholic fatty liver diseases. The adverse effects are primarily gastrointestinal. Therefore, GLP-1 analogs can benefit other conditions besides traditional diabetes and obesity uses.

Association between α-glucosidase inhibitor use and psoriatic disease risk in patients with type 2 diabetes mellitus: A population-based cohort study

AIMS

To investigate the association between the use of alpha-glucosidase inhibitors (AGIs) and the risk of psoriatic disease (ie, psoriasis and psoriatic arthritis) in patients with type 2 diabetes mellitus (T2DM) treated with metformin.

METHODS

Using the 1999-2013 Taiwanese Longitudinal Cohort of Diabetes Patients Database, we identified patients with T2DM who initiated hypoglycaemic treatment between 2003 and 2012. After excluding patients with a history of psoriatic disease (International Classification of Disease, Ninth Revision, Clinical Modification codes 696.0-1) before T2DM diagnosis, patients who received antidiabetic treatment for <90 days, and patients aged <20 or >100 years, we identified 1390 patients who received metformin+AGIs (AGI exposure group) and 47 514 patients who received metformin only (comparison group). We matched the two groups at a 1:10 ratio by age, sex, and index date of T2DM drug use. The association between AGI use and psoriatic disease risk was analysed using a Cox proportional hazard mode; time-dependent covariates for factors were reported in terms of hazard ratios (HRs) with 95% confidence intervals (CIs) after age, sex, T2DM duration, and comorbidities were controlled for.

RESULTS

After adjusting the AGI exposure and comparison groups for potential confounders, we found that psoriatic disease risk was associated with metformin+AGI use when AGI was discontinued for 30 days (HR, 8.77; 95% CI, 1.58-48.5) and when a high AGI dose was administered; furthermore, the risk declined during AGI discontinuation.

CONCLUSIONS

This population-based study reports that AGI use and interruption of AGI use may be associated with increased psoriatic disease risk in treated patients with T2DM.

Unconventional treatment options in psoriasis: A review

Psoriasis is a common skin disease that affects 1-3% of the general population. The treatment depends on body surface area involved, quality of life impairment and associated comorbidities. The treatment options include topical therapy, phototherapy, conventional systemic therapy (methotrexate, cyclosporine and acitretin), biologics and oral small molecules (apremilast and tofacitinib). Despite the availability of newer therapies such as biologics and oral small molecules, many a time, there is a paucity of treatment options due to the chronic nature of the disease, end-organ toxicity of the conventional drugs or high cost of newer drugs. In these scenarios, unconventional treatment options may be utilized as stand-alone or adjuvant therapy. In this review, we have discussed these uncommonly used treatment options in the management of psoriasis.

Clinical effects of antidiabetic drugs on psoriasis: The perspective of evidence-based medicine

Psoriasis and diabetes shared common underlying pathophysiological mechanisms. Emerging data suggested that antidiabetic medications may improve the psoriasis severity in patients with diabetes mellitus. Several hypoglycemic agents including thiazolidinediones, glucagon-like peptide-1 receptor agonists, dipeptidyl peptidase-4 inhibitors, and biguanides have been reported to make a remarkable reduction in the Psoriasis Area and Severity Index score from baseline. This antipsoriatic effect could be mediated not only by the glucose-lowering action of these agents but also via inhibition of keratinocyte over proliferation, increase expression of differentiation markers, suppression the immune inflammatory pathway, and blocking the calcium channels and mitogen-activated protein kinase signaling pathways. On the other hand, there was no significant increase in adverse reactions associated with the treatment of pioglitazone or metformin. However, previous studies often had the relatively short duration of the trials, and did not have enough power to assess recurrence of psoriasis. Potential bias in the study and missing data could undermine the reliability of the results. Therefore, the appropriately randomized controlled studies with large sample sizes and long-term durations in various psoriasis patients are warranted for further support.

The role of incretins and incretin-based drugs in autoimmune diseases

Incretin hormones, including glucagon-like peptide (GLP)-1, GLP-2 and glucose-dependent insulinotropic polypeptide (GIP), are gastrointestinal peptides secreted from enteroendocrine cells. These hormones play significant roles in many physiological processes via binding to G-protein coupled receptors (GPCRs) on different organs and tissues; one of them is the immunomodulatory effect on the immune system and its molecular components such as cytokines and chemokines. Anti-inflammatory effects of incretins and dependent molecules involving long-acting analogs and DPP4 inhibitors through regulation of T and B cell activation may attenuate autoimmune diseases caused by immune system disorders in mistakenly recognizing self as the foreign agent. In this review, we investigate incretin effects on the immune system response and the potential benefits of incretin-based therapy for treating autoimmune diseases.

Efficacy of GLP-1rA, liraglutide, in plaque psoriasis treatment with type 2 diabetes: a systematic review and meta-analysis of prospective cohort and before-after studies

BACKGROUND

Psoriasis usually accompanies comorbidities such as type 2 diabetes, obesity, and cardiovascular disease. It has been proposed that glucagon-like peptide-1 receptor (GLP-1R) agonists used in the treatment of patients with type 2 diabetes may also improve psoriasis. However, the number of patients in every single study is relatively small.

OBJECTIVES

We carried out a meta-analysis to evaluate whether GLP-1R is effective for the treatment of plaque psoriasis with type 2 diabetes.

METHODS

A search of PubMed, Ovid Embase, the Cochrane Library for controlled trials was done from inception to June 20th, 2020. Published trials that included psoriasis patients with type 2 diabetes, the Psoriasis Area and Severity Index (PASI) of treated by GLP-1R before and after. All statistical analyses were conducted using the Stata 15.0 (Stata Corporation, College Station, TX, USA).

RESULTS

There were 4 trials involving 32 patients. Patients treated by GLP-1R after showed significantly lower PASI (SMD: -4.332, 95% CI: -7.611 to -1.053, p = .01), lower fasting plasma glucose than treated before (SMD: -0.341, 95% CI: -0.679 to -0.004, p = .048). There was no significant difference in Body Mass Index (BMI), Dermatology Life Quality Index (DLQI), and glycated hemoglobin (HbA1c) between treated by GLP-1R after and before.

CONCLUSIONS

GLP-1rA, liraglutide, therapy can reduce psoriasis who had concomitant type 2 diabetes severity, but may independently of changes in weight and glycaemic control.

GLP-1 receptor agonists in the treatment of type 2 diabetes - state-of-the-art

BACKGROUND

GLP-1 receptor agonists (GLP-1 RAs) with exenatide b.i.d. first approved to treat type 2 diabetes in 2005 have been further developed to yield effective compounds/preparations that have overcome the original problem of rapid elimination (short half-life), initially necessitating short intervals between injections (twice daily for exenatide b.i.d.).

SCOPE OF REVIEW

To summarize current knowledge about GLP-1 receptor agonist.

MAJOR CONCLUSIONS

At present, GLP-1 RAs are injected twice daily (exenatide b.i.d.), once daily (lixisenatide and liraglutide), or once weekly (exenatide once weekly, dulaglutide, albiglutide, and semaglutide). A daily oral preparation of semaglutide, which has demonstrated clinical effectiveness close to the once-weekly subcutaneous preparation, was recently approved. All GLP-1 RAs share common mechanisms of action: augmentation of hyperglycemia-induced insulin secretion, suppression of glucagon secretion at hyper- or euglycemia, deceleration of gastric emptying preventing large post-meal glycemic increments, and a reduction in calorie intake and body weight. Short-acting agents (exenatide b.i.d., lixisenatide) have reduced effectiveness on overnight and fasting plasma glucose, but maintain their effect on gastric emptying during long-term treatment. Long-acting GLP-1 RAs (liraglutide, once-weekly exenatide, dulaglutide, albiglutide, and semaglutide) have more profound effects on overnight and fasting plasma glucose and HbA1c, both on a background of oral glucose-lowering agents and in combination with basal insulin. Effects on gastric emptying decrease over time (tachyphylaxis). Given a similar, if not superior, effectiveness for HbA1c reduction with additional weight reduction and no intrinsic risk of hypoglycemic episodes, GLP-1RAs are recommended as the preferred first injectable glucose-lowering therapy for type 2 diabetes, even before insulin treatment. However, GLP-1 RAs can be combined with (basal) insulin in either free- or fixed-dose preparations. More recently developed agents, in particular semaglutide, are characterized by greater efficacy with respect to lowering plasma glucose as well as body weight. Since 2016, several cardiovascular (CV) outcome studies have shown that GLP-1 RAs can effectively prevent CV events such as acute myocardial infarction or stroke and associated mortality. Therefore, guidelines particularly recommend treatment with GLP-1 RAs in patients with pre-existing atherosclerotic vascular disease (for example, previous CV events). The evidence of similar effects in lower-risk subjects is not quite as strong. Since sodium/glucose cotransporter-2 (SGLT-2) inhibitor treatment reduces CV events as well (with the effect mainly driven by a reduction in heart failure complications), the individual risk of ischemic or heart failure complications should guide the choice of treatment. GLP-1 RAs may also help prevent renal complications of type 2 diabetes. Other active research areas in the field of GLP-1 RAs are the definition of subgroups within the type 2 diabetes population who particularly benefit from treatment with GLP-1 RAs. These include pharmacogenomic approaches and the characterization of non-responders. Novel indications for GLP-1 RAs outside type 2 diabetes, such as type 1 diabetes, neurodegenerative diseases, and psoriasis, are being explored. Thus, within 15 years of their initial introduction, GLP-1 RAs have become a well-established class of glucose-lowering agents that has the potential for further development and growing impact for treating type 2 diabetes and potentially other diseases.

Is Metformin a Possible Beneficial Treatment for Psoriasis? A Scoping Review

Psoriasis is a chronic inflammatory condition with genetic, immunological, and metabolic etiology. The link between psoriasis and diabetes mellitus has been shown in genetic predisposition, environmental influences, inflammatory pathways, and insulin resistance, resulting in end-organ damage in both conditions. Because comorbidities often accompany psoriasis, the therapeutic management of the disease must also take into consideration the comorbidities. Given that metformin’s therapeutic role in psoriasis is not yet fully elucidated, we raised the question of whether metformin is a viable alternative for the treatment of psoriasis. We conducted this scoping review by searching for evidence in PubMed, Cochrane, and Scopus databases, and we used an extension for scoping reviews (PRISMA-ScR). Current evidence suggests that metformin is safe to use in psoriasis. Studies have shown an excellent therapeutic response to metformin in patients with psoriasis and comorbidities such as diabetes, metabolic syndrome, and obesity. There is no clear evidence supporting metformin monotherapy in patients with psoriasis without comorbidities. There is a need to further evaluate metformin in larger clinical trials, as a therapy in psoriasis.

Psoriatic arthritis and the association with cardiometabolic disease: a narrative review

Psoriatic arthritis (PsA) is associated with a higher burden of cardiometabolic disorders, such as hypertension, dyslipidemia, diabetes, obesity, and cardiovascular disease (CVD), compared with the general population. These comorbidities are associated with the severity of disease, and adversely affect treatment outcomes in PsA. Comorbidities lead to increased physician visits and medications for patients and make the selection and maintenance of therapies challenging for physicians. Moreover, CVD is a leading cause of mortality in PsA. Therefore, optimal management of PsA should include not only treating the skin and joint disease, but also identifying comorbidities early, and managing them to improve long-term outcomes. Further studies are needed to understand the complex mechanisms, interactions, and trajectories of cardiometabolic comorbidities in psoriatic disease.

Effects of antidiabetic drugs on psoriasis: A meta-analysis

BACKGROUND

Psoriasis, a chronic inflammatory skin disease, poses an elevated risk of developing diabetes mellitus.

PURPOSE

To investigate the effects of antidiabetic medications on psoriasis.

DATA SOURCES, STUDY SELECTION AND DATA EXTRACTION

We conducted a systemic review and meta-analysis and searched MEDLINE, EMBASE and CENTRAL for relevant randomized controlled trials. Our outcomes included 75% improvement in the psoriasis area and severity index from baseline (PASI 75), change in the psoriasis area and severity index (PASI) score, or change in the Dermatology Life Quality Index score under antidiabetic agents. Cochrane Collaboration's tool was used to evaluate the risk of bias of included studies. Subgroup analysis of different dosages of the antidiabetic agents was also performed.

DATA SYNTHESIS

We included 10 randomized controlled studies examining the effect of antidiabetic agents. Eight studies were rated high risk of bias. Pioglitazone demonstrated significant increase in PASI 75 (risk difference = 0.42; 95% CI: 0.18-0.65) and decrease in mean PASI (mean difference = -3.82; 95% CI: -6.05-1.ㄍ59). In subgroup analysis, 30 mg pioglitazone group demonstrated a significantly higher portion of PASI 75 than 15 mg pioglitazone group (P = .003).

LIMITATIONS

Some biases are reported high risk in involved articles. The main limitation of the study is in the inclusion of only glitazones. The lack of effect was seen for rosiglitazone and metformin. In the case of metformin, there was only one study available, which is also an important issue.

CONCLUSIONS

The current evidence demonstrates therapeutic efficacy of pioglitazone, which may be a treatment option in patients with psoriasis and diabetes mellitus.

Glucagon-like peptide-1 receptor agonist liraglutide therapy for psoriasis patients with type 2 diabetes: a randomized-controlled trial

OBJECTIVE

There were some clinical studies on GLP-1R agonist liraglutide therapy for psoriasis patients with type 2 diabetes, but there is a lack of randomized controlled trials and the mechanism of which remains unclear.

METHOD

A total of 25 psoriasis patients with type 2 diabetes were randomized 1: 1 divided into the control group (n = 13) or liraglutide group (n = 12) for 12 weeks. We determined the PASI, the DLQI, histopathology of psoriasis skin, and the expression of IL-17, IL-23, and TNF-α in the psoriasis skin.

RESULTS

After 12 weeks of treatment, the mean DLQI of the treatment group decreased from 22.00 ± 5.85 to 3.82 ± 3.60 (p < .05). Compared to week 12, the change in the baseline value of PASI and DLQI in the treatment group showed a significant difference compared with the control group (p < .05). The pathological changes of psoriasis skin and the expression of IL-17, IL-23, TNF-α in the psoriasis skin were improved in the treatment group. No serious adverse events occurred.

CONCLUSION

The skin lesions in psoriasis patients with type 2 diabetes were significantly improved after treatment with liraglutide, which may be related to the inhibition of the expression of inflammatory factors such as IL-23, IL-17, and TNF-α.

Psoriasis and Cardiovascular Risk: A Comprehensive Review

Psoriasis is a systemic inflammatory disorder that involves complex pathogenic interactions between the innate and adaptive immune systems. Individuals with psoriasis have an increased risk of developing other chronic health diseases such cardiovascular disorders. The high incidence of cardiovascular events in the population with psoriasis could be explained by several mechanisms. The high prevalence of traditional cardiovascular risk factors and metabolic abnormalities contributes to the high cardiovascular burden in patients with psoriasis. Likewise, the presence of systemic inflammation in combination with metabolic abnormalities may act in a synergistic manner to increase cardiovascular risk in these patients. This review focused on epidemiologic and clinical evidence linking psoriasis to cardiovascular risk factors and cardiovascular disease. We described the possible pathophysiological mechanisms that justify this association and analyzed the best way to stratify the cardiovascular risk in patients with psoriasis. We also described the usefulness of the therapies frequently used in cardiovascular prevention and analyzed the impact of the specific psoriasis medication on cardiovascular risk factors or major atherosclerotic events. Knowledge of the application of different cardiovascular prevention strategies could mean an advantage in performing the difficult task of estimating cardiovascular risk and treating cardiovascular risk factors in this particular group of patients.

Recent advances in understanding the role of glucagon-like peptide 1

The discovery that glucagon-like peptide 1 (GLP-1) mediates a significant proportion of the incretin effect during the postprandial period and the subsequent observation that GLP-1 bioactivity is retained in type 2 diabetes (T2D) led to new therapeutic strategies being developed for T2D treatment based on GLP-1 action. Although owing to its short half-life exogenous GLP-1 has no use therapeutically, GLP-1 mimetics, which have a much longer half-life than native GLP-1, have proven to be effective for T2D treatment since they prolong the incretin effect in patients. These GLP-1 mimetics are a desirable therapeutic option for T2D since they do not provoke hypoglycaemia or weight gain and have simple modes of administration and monitoring. Additionally, over more recent years, GLP-1 action has been found to mediate systemic physiological beneficial effects and this has high clinical relevance due to the post-diagnosis complications of T2D. Indeed, recent studies have found that certain GLP-1 analogue therapies improve the cardiovascular outcomes for people with diabetes. Furthermore, GLP-1-based therapies may enable new therapeutic strategies for diseases that can also arise independently of the clinical manifestation of T2D, such as dementia and Parkinson's disease. GLP-1 functions by binding to its receptor (GLP-1R), which expresses mainly in pancreatic islet beta cells. A better understanding of the mechanisms and signalling pathways by which acute and chronic GLP-1R activation alleviates disease phenotypes and induces desirable physiological responses during healthy conditions will likely lead to the development of new therapeutic GLP-1 mimetic-based therapies, which improve prognosis to a greater extent than current therapies for an array of diseases.

Neurotransmitters, neuropeptides and their receptors interact with immune response in healthy and psoriatic skin

Psoriasis is a chronic inflammatory disease with a multifactorial origin that affects the skin. It is characterized by keratinocyte hyperproliferation, which results in erythemato-squamous plaques. Just as the immune system plays a fundamental role in psoriasis physiopathology, the nervous system maintains the inflammatory process through the neuropeptides and neurotransmitters synthesis, as histamine, serotonin, calcitonin gene-related peptide, nerve growth factor, vasoactive intestinal peptide, substance P, adenosine, glucagon-like peptide, somatostatin and pituitary adenylate cyclase polypeptide. In patients with psoriasis, the systemic or in situ expression of these chemical mediators and their receptors are altered, which affects the clinical activity of patients due to its link to the immune system, provoking neurogenic inflammation. It is important to establish the role of the nervous system since it could represent a therapeutic alternative for psoriasis patients. The aim of this review is to offer a detailed review of the current literature about the neuropeptides and neurotransmitters involved in the physiopathology of psoriasis.

Does weight loss reduce the severity and incidence of psoriasis or psoriatic arthritis? A Critically Appraised Topic

CLINICAL QUESTION

Does weight loss reduce the severity and incidence of psoriasis or psoriatic arthritis (PsA) in obese individuals?

BACKGROUND

Obesity presents a rising public health challenge and is more prevalent among individuals with psoriasis or PsA than in the general population. Longitudinal population-based studies suggest a causal role for obesity in psoriasis and PsA onset and that obesity drives greater disease severity.

METHODS

We systematically reviewed evidence within the MEDLINE, Embase and CENTRAL databases and clinical trials registries examining lifestyle, pharmacological and surgical weight loss interventions in the treatment and prevention of psoriasis and PsA in obese individuals. Meta-analysis was conducted using random-effects models, followed by sensitivity analyses.

RESULTS

Of 176 full-text articles reviewed, 14 met the inclusion criteria. Meta-analysis of six randomized control trials (RCTs) confirmed that weight loss following lifestyle interventions (diet or physical activity) improves psoriasis compared with control [mean change in Psoriasis Area and Severity Index -2·59, 95% confidence interval (CI) -4·09 to -1·09; P < 0·001]. One RCT demonstrated a greater likelihood of achieving minimal PsA activity following diet-induced weight loss (odds ratio 4·20, 95% CI 1·82-9·66; P < 0·001). Three studies of pharmacological treatments reported conflicting results, and no RCTs of bariatric surgery were identified. Two cohort studies suggested that bariatric surgery, particularly gastric bypass, reduces the risk of developing psoriasis (hazard ratio 0·52, 95% CI 0·33-0·81; P < 0·01).

CONCLUSIONS

These limited data indicate that weight loss can improve pre-existing psoriasis and PsA, and prevent the onset of psoriasis in obese individuals. Together with the National Institute for Health and Care Excellence obesity guidance, this informed a local obesity screening and management pathway, providing multidisciplinary weight loss interventions alongside conventional skin-focused care for patients with psoriasis.

Glucose metabolism in patients with psoriasis

BACKGROUND

Epidemiological studies strongly suggest that psoriasis predisposes to type 2 diabetes. Several theories have been proposed to explain how these disease entities might be pathophysiologically connected.

OBJECTIVES

Our primary objective was to elucidate whether clinical data support the notion of common pathophysiological denominators in patients with psoriasis and type 2 diabetes, and thus to delineate the association between the two conditions that has arisen on the basis of epidemiological studies.

METHODS

We reviewed clinical studies investigating parameters of glucose metabolism in patients with psoriasis. The PubMed and Embase databases were searched for studies investigating glucose metabolism in adult patients with psoriasis as a primary or secondary end point. Studies had to include a relevant control group.

RESULTS

Twenty-six clinical studies reporting on insulin resistance, glucose tolerance or insulin secretion were eligible for review. The results were widely conflicting, with less than half of the studies showing results suggestive of defective glucose metabolism in patients with psoriasis. In general, the studies suffered from a lack of information regarding possible confounders and patient characteristics. Furthermore, the research methods varied, and in all but one study they might not have been appropriate to detect early and subtle defects in glucose metabolism.

CONCLUSIONS

The available literature does not unequivocally support common pathophysiological denominators in psoriasis and type 2 diabetes. Well-designed clinical studies are needed to expose potential diabetogenic defects in the glucose metabolism in patients with psoriasis.

Glucagon-like peptide-1 analogue liraglutide facilitates wound healing by activating PI3K/Akt pathway in keratinocytes

AIMS

Diabetes induces various skin troubles including foot ulcer. This type of skin ulcer is refractory but the pathogenesis is not so certain. Recent study show that glucagon-like peptide-1 (GLP-1) analogues reduce foot complications with diabetes (Pérez et al., 2015), however, the role of GLP-1/GLP-1R axis is not fully understood, and clear evidence of GLP-1 to facilitate wound closure is still lacking. In this study, we investigated whether a potent GLP-1R agonist liraglutide affects wound healing process.

METHODS

The expression of GLP-1R in HaCaT cells were indentified by quantitative reverse-transcription polymerase chain reaction (qRT-PCR) and immunoblotting analysis. To assess the effect on wound closure in keratinocytes, we performed in vitro scratch assay using the IncuCyte system (Essen BioSciences, Ann Arborm MI). We applied ointment containing liraglutide on full-thickness wounds in the dorsum of female balb/c mice (n = 6) until healing. To investigate the effect on PI3K/Akt pathway, we used IncuCyte system in HaCaT treated with PI3K inhibitor and Akt inhibitor.

RESULTS

Keratinocytes expressed GLP-1R and liraglutide induced their migration. Liraglutide facilitated the wound healing in mice. Liraglutide upregulated keratinocyte migration via PI3K/Akt activation.

CONCLUSIONS

Our study suggests that liraglutide may be a potential target drug to improve skin ulcer with diabetes through its specific receptor GLP-1.

Treatment with GLP1 receptor agonists reduce serum CRP concentrations in patients with type 2 diabetes mellitus: A systematic review and meta-analysis of randomized controlled trials

AIM

To undertake a systematic review and meta-analysis of randomized controlled trials of the effect of glucagon-like peptide-1 receptor agonist (GLP-1 RAs) therapy on serum C-reactive protein (CRP) concentrations.

METHOD

PubMed-Medline, SCOPUS, Web of Science and Google Scholar databases were searched for the period up until March 16, 2016. Prospective studies evaluating the impact of GLP-1 RAs on serum CRP were identified. A random effects model (using the DerSimonian-Laird method) and generic inverse variance methods were used for quantitative data synthesis. Sensitivity analysis was conducted using the leave-one-out method. Heterogeneity was quantitatively assessed using the I² index. Random effects meta-regression was performed using unrestricted maximum likelihood method to evaluate the impact of potential moderator. International Prospective Register for Systematic Reviews (PROSPERO) number CRD42016036868.

RESULTS

Meta-analysis of the data from 7 treatment arms revealed a significant reduction in serum CRP concentrations following treatment with GLP-1 RAs (WMD -2.14 (mg/dL), 95% CI -3.51, -0.78, P=0.002; I² 96.1%). Removal of one study in the meta-analysis did not change the result in the sensitivity analysis (WMD -2.14 (mg/dL), 95% CI -3.51, -0.78, P=0.002; I² 96.1%), indicating that our results could not be solely attributed to the effect of a single study. Random effects meta-regression was performed to evaluate the impact of potential moderator on the estimated effect size. Changes in serum CRP concentration were associated with the duration of treatment (slope -0.097, 95% CI -0.158, -0.042, P<0.001).

CONCLUSIONS

This meta-analysis suggests that GLP-1 RAs therapy causes a significant reduction in CRP.

Dipeptidyl peptidase-4 inhibition and narrow-band ultraviolet-B light in psoriasis (DINUP): study protocol for a randomised controlled trial

BACKGROUND

Moderate to severe psoriasis is a systemic inflammatory disease associated with insulin resistance, obesity and type 2 diabetes (T2DM). Sitagliptin is a dipeptidyl peptidase-4 (DPP-4) inhibitor that improves glycaemia and has a marketing authorisation for the treatment of T2DM. Non-immunosuppressive therapies that are effective for psoriasis and its associated comorbidities would be a significant advance in the treatment of this chronic disease.

METHODS/DESIGN

This is a single centre, 39-week, prospective, randomised, open label, clinical trial of oral sitagliptin (Januvia(®)) in psoriasis patients who are due to undergo a course of narrow-band ultraviolet-B (NB-UVB) phototherapy. We plan to enrol 120 participants and allocate participants on a random and 1:1 basis to receive sitagliptin 100 mg daily for 24 weeks combined with NB-UVB or NB-UVB monotherapy. Participants will be followed up for 12 weeks after sitagliptin therapy is discontinued. The primary endpoint is the change in Psoriasis Area and Severity Index (PASI) 24 weeks after treatment initiation. Secondary endpoints include cumulative NB-UVB dose, number of NB-UVB treatments required to clear psoriasis, proportions of participants who achieve PASI-50 (50 % reduction in PASI from baseline), PASI-75, PASI-90 and the proportion of participants who relapse in each group. We will also analyse changes in cardiovascular disease risk factors, serum cytokine and hormone levels and peripheral blood mononuclear expression of immune proteins at 24 and 36 weeks. A subgroup of participants will have skin biopsies taken and analysed for skin levels and expression of immune cells, receptors, hormones and immune proteins. The genetic or epigenetic profile that predicts best response to DPP-4 inhibitor therapy will be analysed. The safety endpoints include the rate and severity of adverse events.

DISCUSSION

This is the first randomised clinical trial assessing dipeptidyl peptidase-4 inhibition therapy in psoriasis. We hypothesise that sitagliptin therapy in combination with NB-UVB improves psoriasis severity compared to NB-UVB monotherapy.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier NCT02347501 (Date of registration: 27 January 2015).