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IκBζ plays a key role in psoriasis by mediating IL-17A–driven effects, but the molecular mechanism by which IL-17A regulates IκBζ expression is not clarified. We sought to explore the molecular transformation in patients with psoriasis during anti-IL-17A (secukinumab) treatment with a focus on IκBζ. The study was an open-label, single-arm, single-center secukinumab treatment study that included 14 patients with plaque psoriasis. Skin biopsy specimens and blood samples were collected on days 0, 4, 14, 42, and 84 and processed for microarray gene expression analysis. Furthermore, in vitro experiments with human keratinocytes and synovial fibroblasts were conducted. Secukinumab improved clinical scores and histologic psoriasis features. Moreover, secukinumab altered the skin transcriptome. The major transcriptional shift appeared between day 14 and day 42 after treatment initiation, although 80 genes were differentially expressed already at day 4. Expression of nuclear factor of kappa light polypeptide gene enhancer in B cells inhibitor (IκB) ζ (NFKBIZ , the gene encoding IκBζ) was reduced already after 4 days of treatment in the skin. NFKBIZ expression correlated to Psoriasis Area and Severity Index score, and NFKBIZ mRNA levels in the skin decreased during anti–IL-17A treatment. Moreover, specific NFKBIZ signature genes were significantly altered during anti–IL-17A treatment. Finally, we identified NF-κB activator 1 (Act1), p38 mitogen-activated protein kinase (MAPK), Jun NH2-terminal kinase (JNK), and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) as key signaling pathways in NFKBIZ/ IκBζ regulation. Our results define a crucial role for IκBζ in the antipsoriatic effect of secukinumab. Because IκBζ signature genes were regulated already after 4 days of treatment, this strongly indicates that IκBζ plays a crucial role in the antipsoriatic effects mediated by anti–IL-17A treatment. [ABSTRACT FROM AUTHOR]

Background: Ixekizumab, a high-affinity monoclonal antibody that selectively targets interleukin 17A, is efficacious in treating moderate-to-severe plaque psoriasis through 60 weeks.Objective: To evaluate the efficacy and safety of ixekizumab through 108 weeks of treatment in UNCOVER-3.Methods: Patients (N = 1346) were randomized 2:2:2:1 to 80 mg ixekizumab every 2 or 4 weeks, 50 mg etanercept twice weekly, or placebo. At week 12, patients switched to ixekizumab every 4 weeks during a long-term extension (LTE) period. Efficacy data were summarized using as-observed, multiple imputation (MI), and modified MI (mMI) methods.Results: For patients (N = 385) receiving the recommended dose (ixekizumab every 2 weeks on weeks 0-12 and every 4 weeks during LTE), the 108-week as-observed, MI, and mMI response rates were 93.4%, 88.3%, and 83.6%, respectively, for patients achieving ≥75% improvement from baseline in the Psoriasis Area and Severity Index, and the 108-week as-observed, MI, and mMI response rates were 82.6%, 78.3%, and 74.1%, respectively, for patients with a static Physician's Global Assessment score of 0 or 1. During LTE, 1077 (84.5%) patients reported ≥1 treatment-emergent adverse event, and 85% were mild or moderate in severity. Discontinuation because of adverse events occurred in 6.4% of patients.Limitations: There was no comparison treatment group after week 12.Conclusion: Ixekizumab is well tolerated and demonstrates persistent efficacy through 108 weeks. [ABSTRACT FROM AUTHOR]

Contrary to their terrestrial counterparts, freshwater plants are linked to flooding dynamics associated with their habitats in or around water. Gas diffusivity, light availability, nutrient concentrations, and flow velocity select not only on freshwater eco-physiological adaptive traits but also on general plant functional traits, such as plant height or specific leaf area. Emerging stressors under global change impact freshwater plant functions at different temporal and spatial scales via both trait–trait and trait–environment relationships. Predicting how freshwater plant communities are changing and the reciprocal relationships between freshwater plant functions and the environment will require a focus on the specific conditions and traits important for a life in water. Freshwater ecosystems are of worldwide importance for maintaining biodiversity and sustaining the provision of a myriad of ecosystem services to modern societies. Plants, one of the most important components of these ecosystems, are key to water nutrient removal, carbon storage, and food provision. Understanding how the functional connection between freshwater plants and ecosystems is affected by global change will be key to our ability to predict future changes in freshwater systems. Here, we synthesize global plant responses, adaptations, and feedbacks to present-day and future freshwater environments through trait-based approaches, from single individuals to entire communities. We outline the transdisciplinary knowledge benchmarks needed to further understand freshwater plant biodiversity and the fundamental services they provide. [ABSTRACT FROM AUTHOR]

Background Data on subsequent cancers, prognostic factors for mortality, and causes of death are limited in mycosis fungoides (MF) and parapsoriasis. Objectives To assess subsequent cancers, mortality, and causes of death in MF and parapsoriasis. Methods Using the Danish nationwide population-based registries, we identified 368 MF patients and 582 parapsoriasis patients and compared them with the general Danish population for subsequent cancers, mortality, and causes of death. Results Subsequent cancers were significantly increased in parapsoriasis patients (standardized incidence ratio [SIR], 2.0 [95% confidence interval {CI}, 1.6-2.5]), and a trend was observed in MF (SIR, 1.2 [95% CI, 0.9-1.5]). Mortality was significantly increased in MF (SIR, 2.0 [95% CI, 1.8-2.3]) and parapsoriasis (SIR, 1.3 [95% CI, 1.1-1.5]). Excess mortality from MF was highest during the first 5 years of follow-up, and causes of increased death included both malignant and nonmalignant diseases. Limitations We have no information regarding clinical stage, treatments, and patient lifestyles. Conclusion Patients with parapsoriasis had a significantly increased risk of subsequent cancers and increased mortality. In addition, the highest excess mortality in the MF group was observed during the first 5 years of follow-up, which suggests that MF exists in both an aggressive and a more indolent form. [ABSTRACT FROM AUTHOR]

Functional biogeography has advanced the field of functional ecology into a more spatially predictive science. However, freshwater plants are still underrepresented in these trait based advancements. Here, we argue that there is a need for developing a functional biogeographical framework for freshwater plants and initiate global mapping efforts focusing on the form and function of freshwater plants. Specific attention should be given to (1) the placement of freshwater plants in the global plant trait space and show how this placement links to global trait environment relationships; (2) the theoretical framework for major structural trait trait correlations based on the physical constraints in aquatic ecosystems; (3) the evolutionary and environmental drivers underlying the global distribution of inter and intra specific variation in different life forms; and (4) the level of equilibrium between spatial and temporal trait environment relationships in freshwater plants. By putting freshwater plants in the context of these spatial aspects, we could advance our understanding of freshwater plant adaptations and responses to environmental gradients, and thereby facilitate predicting the consequences of global changes for freshwater ecosystem functions and services. [Display omitted] • Freshwater plants have been underexamined in the context of functional biogeography. • Global mapping efforts focusing on their form and function are needed. • This will help advance our understanding of freshwater plant unique adaptations. • Such an exercise will be accomplished by the MAP Project (www.lifeinmud.com/map). • We are recruiting collaborators from around the world, starting in late 2021. [ABSTRACT FROM AUTHOR]

Background: Current guidelines broadly recommend comprehensive cardiac rehabilitation (CCR), although evidence for this is still limited. We investigated the 12-month effect of hospital-based CCR versus usual care (UC) for a broadly defined group of cardiac patients within the modern therapeutic era of cardiology. Methods: We conducted a centrally randomized single-center clinical trial with blinded assessment of the primary outcome: registry-based composite of total mortality, myocardial infarction, or acute first-time readmission due to heart disease. Other outcomes were hospitalization, risk profile, and quality of life. The trial included 770 participants (20-94 years) with congestive heart failure (12%), ischemic heart disease (58%), or high risk of ischemic heart disease (30%). Comprehensive cardiac rehabilitation is composed of 6 weeks of intensive intervention and systematic follow-up for 10.5 months. Results: We randomized 380 patients to CCR versus 390 to UC. Randomization was well balanced. The primary outcome occurred in 31% of both groups (relative risk 0.96, 95% confidence interval 0.78-1.26). Compared with the UC group, CCR significantly reduced length of stay by 15% (95% confidence interval 1.1%-27.1%, P = .04), mean number of cardiac risk factors above target (4.5 vs 4.1, P = .01), patients with systolic blood pressure below target (P = .003), physically inactivity (P = .01), and unhealthy dietary habits (P = .0003). Short-Form-36 and Hospital Anxiety and Depression Scale did not differ significantly. Conclusion: At 12 months, the CCR and UC groups did not differ regarding the primary composite outcome. Comprehensive cardiac rehabilitation significantly reduced length of hospital stay and improved cardiac risk factors. [Copyright &y& Elsevier]

Summary1α,25(OH)2D3 and its analogs are potent mediators of keratinocyte differentiation in vitro. The precise mechanism of this action is still unknown. The nuclear transcription factor activator protein 1 seems to play an important role in keratinocyte differentiation. The purpose of this study was to investigate the effect of 1α,25(OH)2D3 on activator protein 1 DNA binding activity in cultured human keratinocytes. In a time-course study of human keratinocytes incubated with 1α,25(OH)2D3 (10-7-10-11 M) a significant dose-dependent increase in activator protein 1 DNA binding activity as determined by electrophoretic mobility shift assay was seen after 36 h. This increase was followed by a significant dose-dependent decrease in activator protein 1 DNA binding activity after 72 h. When differentiation was induced by raising the calcium concentration in the culture medium from 0.09 to 0.3 mM a similar increase in activator protein 1 DNA binding activity was observed after incubation for 48 h. Pharmacologic down-modulation of the protein kinase C activity with GF 109203X reversed the calcium-induced increase in activator protein 1 DNA binding activity and abolished keratinocyte differentiation as determined by a transglutaminase assay. In contrast, activator protein 1 DNA binding activity and keratinocyte differentiation were not affected when protein kinase C activity was down-modulated in the experiments with 1α,25(OH)2D3. The activator protein 1 complex in human keratinocytes consists of dimers of Fra-1, Fra-2, c-Jun, JunD, and c-Fos. Our results demonstrate that 1α,25(OH)2D3- and calcium-induced keratinocyte differentiation are accompanied by changes in activator protein 1 DNA binding activity. Protein kinase C activation appears to be essential for the calcium-dependent induction of keratinocyte differentiation, whereas a protein-kinase-C-independent activation of activator protein 1 DNA binding and keratinocyte differentiation is responsible for the 1α,25(OH)2D3-induced effects. [ABSTRACT FROM AUTHOR]

In order to delineate the biochemical events in the nuclear compartment of an in vivo proliferating epidermis, we produced a model of hyperproliferative epidermis by topical application of docosahexaenoic acid (22:6n-3) on guinea pig skin. Employing this model we demonstrated: (i) that protein kinase C (PKC)-α and atypical PKC-ζ are the two major PKC isozymes in the normal epidermal nuclear membrane, in contrast to PKC-α and PKC-β in the epidermal plasma membrane; (ii) that topical application of docosahexaenoic acid induced epidermal hyperproliferation and enhanced total nuclear PKC, particularly nuclear PKC-α and the atypical PKC-ζ isozymes. The increase in the nuclear PKC isozymes paralleled a marked increase in the expression of nuclear mitogen-activated protein-kinase. These data suggest that epidermal hyperproliferative activity is accompanied by the upregulation of nuclear PKC/mitogen-activated protein-kinase signaling pathway. [ABSTRACT FROM AUTHOR]

In the present study, keratinocytes were coincubated with human neutrophils to determine whether or not an increase in leukotriene B4 formation can occur. Human keratinocytes used were cultured in serum-free, low-calcium medium, whereas neutrophils were purified from heparinized venous blood. After coincubations, formation of leukotriene B4 was determined by reversed-phase high-performance liquid chromatography, coupled with its characteristic UV scan. Confirmation and quantification was by radioimmunoassay. Our data revealed that incubations of keratinocytes (1.5 × 106) alone stimulated with calcium ionophore resulted in no detectable amounts of leukotriene B4. In contrast, incubations of neutrophils (5 × 106) alone resulted in the generation of 62.2 ± 8.5 ng of LTB4. Coincubations of the neutrophils with keratinocytes (ratio 3:1) resulted in a 56-163% increase in leukotriene B4 formation. To delineate the source of the newly formed leukotriene B4, incubations of keratinocytes with leukotriene A4 revealed that keratinocytes can transform leukotriene A4 into leukotriene B4. These latter findings indicate that although keratinocytes cannot directly metabolize arachidonic acid into leukotriene B4 via the 5-lipoxygenase enzyme, they can transform neutrophil-derived leukotriene A4 into leukotriene B4, thus indicating the possible existence of a putative keratinocyte-leukotriene A4 hydrolase. It is therefore reasonable to speculate that the keratinocytes possess the capacity to generate leukotriene B4 in the epidermis when provided leukotriene A4 and thereby can amplify the inflammatory processes occurring during crophil exocytosis. [ABSTRACT FROM AUTHOR]

Background Mycosis fungoides (MF) and parapsoriasis are characterized by malignant proliferation and chronic inflammation, which may affect the risk for venous thromboembolism (VTE). Objectives To examine the risk for VTE in patients with MF and parapsoriasis. Methods We conducted a nationwide population-based cohort study in Denmark to examine the relative risk (RR) of VTE in 525 patients with MF and 634 patients with parapsoriasis compared with that in sex- and age-matched controls from the general population. Results In patients with MF, the 10-year absolute risk for VTE was 3.4% (95% confidence interval [CI], 2.0-5.4). The adjusted RRs were 2.41 (95% CI, 1.49-3.90) for VTE and 4.01 (95% CI, 2.16-7.46) for pulmonary embolism. Notably, within the first 5 years after diagnosis with MF, the RR of pulmonary embolism was increased 6.7-fold (to 6.71 [95% CI, 2.86-15.72]). Patients with parapsoriasis had a 2.7-fold increased RR of VTE (to 2.67 [95% CI, 1.32-5.40]) in the absence of other established VTE risk factors. Limitations We had no information regarding disease stage of MF and prescribed drugs. Conclusion Patients with MF and parapsoriasis had an increased RR of VTE, although the absolute risk remained low. These findings should increase awareness of comorbidities in patients with MF and parapsoriasis. [ABSTRACT FROM AUTHOR]

Background: Mycosis fungoides (MF) and parapsoriasis are characterized by malignant proliferation and chronic inflammation, which may affect the risk for venous thromboembolism (VTE).Objectives: To examine the risk for VTE in patients with MF and parapsoriasis.Methods: We conducted a nationwide population-based cohort study in Denmark to examine the relative risk (RR) of VTE in 525 patients with MF and 634 patients with parapsoriasis compared with that in sex- and age-matched controls from the general population.Results: In patients with MF, the 10-year absolute risk for VTE was 3.4% (95% confidence interval [CI], 2.0-5.4). The adjusted RRs were 2.41 (95% CI, 1.49-3.90) for VTE and 4.01 (95% CI, 2.16-7.46) for pulmonary embolism. Notably, within the first 5 years after diagnosis with MF, the RR of pulmonary embolism was increased 6.7-fold (to 6.71 [95% CI, 2.86-15.72]). Patients with parapsoriasis had a 2.7-fold increased RR of VTE (to 2.67 [95% CI, 1.32-5.40]) in the absence of other established VTE risk factors.Limitations: We had no information regarding disease stage of MF and prescribed drugs.Conclusion: Patients with MF and parapsoriasis had an increased RR of VTE, although the absolute risk remained low. These findings should increase awareness of comorbidities in patients with MF and parapsoriasis. [ABSTRACT FROM AUTHOR]

Background: Current guidelines broadly recommend comprehensive cardiac rehabilitation (CR), although evidence for this is still limited. It is not known whether evidence from before 1995 is still valid. Study Design: The DANish Cardiac ReHABilitation (DANREHAB) trial was designed as a centrally randomized clinical trial to clarify whether hospital-based comprehensive CR is superior to usual care for patients with congestive heart failure, ischemic heart disease, or high risk for ischemic heart disease. A combined primary outcome measure included total mortality, myocardial infarction, or readmissions due to heart disease based on linkage to public registries. The CR was an individually tailored, multidisciplinary program (6 weeks of intensive CR and 12 months of follow-up) including patient education, exercise training, dietary counseling, smoking cessation, psychosocial support, risk factor management, and clinical assessment. Study Population: Of 5060 discharged patients, 1614 (32%) were eligible for the trial and 770 patients were randomized (47% of those eligible). Participants were younger (P < .001) and had less comorbidity than nonparticipants (P < .03). Conclusion: Our trial shows that a large-scale, centrally randomized clinical trial on comprehensive CR can be conducted among a broadly defined patient group, but reaching the stipulated number of 1800 patients was difficult. Although the study included relatively many women and older people, elderly patients and patients with high comorbidity were underrepresented, which may influence the external validity. [Copyright &y& Elsevier]

Purpose Cutaneous T-cell lymphomas (CTCLs) are dominated by mycosis fungoides (MF) and Sézary syndrome (SS), and durable disease control is a therapeutic challenge. Standard total skin electron beam therapy (TSEBT) is an effective skin-directed therapy, but the possibility of retreatments is limited to 2 to 3 courses in a lifetime due to skin toxicity. This study aimed to determine the clinical effect of low-dose TSEBT in patients with MF and SS. Methods and Materials In an open clinical study, 21 patients with MF/SS stages IB to IV were treated with low-dose TSEBT over <2.5 weeks, receiving a total dose of 10 Gy in 10 fractions. Data from 10 of these patients were published previously but were included in the current pooled data analysis. Outcome measures were response rate, duration of response, and toxicity. Results The overall response rate was 95% with a complete cutaneous response or a very good partial response rate (<1% skin involvement with patches or plaques) documented in 57% of the patients. Median duration of overall cutaneous response was 174 days (5.8 months; range: 60-675 days). TSEBT-related acute adverse events (grade 1 or 2) were observed in 60% of patients. Conclusions Low-dose (10-Gy) TSEBT offers a high overall response rate and is relatively safe. With this approach, reirradiation at times of relapse or progression is likely to be less toxic than standard dose TSEBT. It remains to be established whether adjuvant and combination treatments can prolong the beneficial effects of low-dose TSEBT. [ABSTRACT FROM AUTHOR]

Protein-tyrosine phosphatases (PTPs) are considered important therapeutic targets because of their pivotal role as regulators of signal transduction and thus their implication in several human diseases such as diabetes, cancer, and autoimmunity. In particular, PTPIB has been the focus of many academic and industrial laboratories because it was found to be an important negative regulator of insulin and leptin signaling, and hence a potential therapeutic target in diabetes and obesity. As a result, significant progress has been achieved in the design of highly selective and potent PTPIB inhibitors. In contrast, little attention has been given to other potential drug targets within the PTP family. Guided by x-ray crystallography, molecular modeling, and enzyme kinetic analyses with wild type and mutant PTPs, we describe the development of a general, low molecular weight, non-peptide, non-phosphorus PTP inhibitor into an inhibitor that displays more than 100-fold selectivity for PTPβ over PTPIB. Of note, our structure-based design principles, which are based on extensive bioinformatics analyses of the PTP family, are general in nature. Therefore, we anticipate that this strategy, here applied to PTPβ, in principle can be used in the design and development of selective inhibitors of many, if not most PTPs. [ABSTRACT FROM AUTHOR]

A new type of planar lipid substrate for Humicola lanuginosa lipase (HLL) has been prepared by depositing a monolayer of 1-mono-oleoyl-rac-glycerol (MOG) on top of a monolayer of dipalmitoyl-phosphatidylcholine (DPPC) on mica by the Langmuir–Blodgett (LB) technique. The bilayer was subsequently exposed to HLL in a liquid cell of an atomic force microscope (AFM) allowing the time course of the lipolytic degradation to be observed. By analysing a series of AFM images, we find that enzymes are preferentially activated at the edge of nano-scale defects present in the bilayer prior to enzyme injection, while defect-free areas of the substrate are surprisingly stable towards enzyme degradation. The initial rate of hydrolysis is found to be proportional to the perimeter length, P, of the initial nano-scale defects as well as the bulk enzyme concentration, cHLL; d(lipid)/dt=k P cHLL. We estimate the specific rate of MOG hydrolysis by HLL to be 2.5×104 MOG molecules/(minute·molecule of HLL). [Copyright &y& Elsevier]

Biodiversity loss has accelerated over the past century and freshwater species overall are among those experiencing greatest declines. Genetic resources have the potential to help evaluate the full magnitude of this loss and represent a key tool to effectively allocate conservation resources and monitor the success of restoration efforts. The full power of genetic resources will be realized when the daunting task of referencing all DNA sequences of freshwater organisms is complete. Here, we quantified the availability and distribution of barcode and genome data for freshwater macroscopic organisms in Canada, a country rich in inland water resources and thus particularly vulnerable to aquatic species losses. Impressively, most inland water species (86 %) were represented by barcodes recorded in the BOLD Systems database, while very few had full genomes available (<4 %) in the NCBI database. We identified barcode data deficiencies in northern regions and for taxa assessed as most at risk or without sufficient information for conservation status classification. As expected, the speciose insect group had a lower-than-average number of records per species and a high proportion of data deficient species without adequate barcode coverage. This study highlights where future sequencing resources should be prioritized within initiatives such as the Canada BioGenome Project and BIOSCAN Canada and provides a workflow that could be applied internationally to inform conservation management plans and to mitigate biodiversity loss. • Paucity of monitoring data limits conservation status assessment of freshwater taxa. • We compiled barcodes and genomes for Canadian inland water-reliant macroorganisms. • 86 % of species had barcodes, however data deficiencies spanned all domains of life. • Insects and species at risk have been under-sampled, especially in Northern regions. • We provide a list of taxa to prioritize future sequencing efforts on. [ABSTRACT FROM AUTHOR]

Ingestion of eggs (ova) of the porcine nematode parasite Trichuris suis (TSO) may reduce the severity of autoimmune disorders, however the development of TSO treatment as a useful therapy for autoimmune diseases is hampered by a lack of knowledge on the development of the parasite and the nature of the local immune responses in humans. Here, we used colonoscopy to investigate the development of T. suis and related mucosal and systemic immune responses during TSO treatment in an intestinally healthy male volunteer. TSO treatment induced T. suis -specific serum antibodies, a transient blood eosinophilia, and increases in IFNγ + and IL4 + cells within the circulating CD4 + T-cell population. Increased expression of genes encoding cytokines ( IL4, IL10, IL17 and TGF-β ), and transcription factors ( FOXP3, GATA3 and RORC ) were apparent in the ascending and transverse colon (the predilection site of the worms), whereas only limited changes in gene expression were observed proximally (ileum) and distally (descending colon) to the infected tissue. We further show that T. suis is able to colonise the human colon, with a number of worms developing to a similar size and morphology observed in the natural pig host, and a small number of unembryonated eggs were passed in the faeces, indicating patent infection. Notably, the volunteer experienced a substantial improvement in psoriasis during the course of TSO treatment. Thus, TSO treatment induced a mixed Th1/Th2/T regulatory response at the local site of infection, which was also reflected to some extent in the peripheral circulation. These results, together with the first definitive observations that T. suis can mature to adult size and reproduce in humans, shed new light on the interaction between the human immune system and probiotic helminth treatment, which should facilitate further development of this novel therapeutic option. [ABSTRACT FROM AUTHOR]

IL-17C is a member of the IL-17 family of cytokines. The expression of IL-17C has been demonstrated to be strongly induced by TNFα in human keratinocytes, and recently the level of IL-17C was found to be increased in the inflammatory skin disease psoriasis. However, little is known about the molecular mechanisms involved in the regulation of IL-17C. Here, we show that pretreatment of cultured human keratinocytes with the inhibitor of κB kinase 2 inhibitor, SC-514, resulted in a significant reduction in both IL-17C mRNA and protein expression, indicating the significance of this pathway in the regulation of IL-17C. NP-κB binding sites were identified upstream from the IL-17C gene, and by electrophoretic mobility shift assay NF-κB was shown to bind to all three identified binding sites. Moreover, NF-κB binding to these sites was inducible by TNFα. Supershift analysis revealed binding of the NF-κB subunits p65 and p50 to all three NP-κB binding sites. To determine the contribution of NF-κB in IL-17C expression, we conducted luciferase gene reporter experiments and demonstrated that a 3204-bp promoter fragment of IL-17C containing three putative NP-κB binding sites was strongly activated by TNFα. Interestingly, mutations of the three NP-κB binding sites revealed that one specific NP-κB binding site was crucial for the TNFα-mediated IL-17C induction because mutation of this specific site completely abolished TNFα-induced IL-17C promoter activation. We conclude that the activation of NP-κB (p65/p50) is crucial for the TNPα-induced stimulation of IL-17C expression in human keratinocytes. [ABSTRACT FROM AUTHOR]

The inflammasome is a cytosolic multiprotein complex with two major functions: recognizing pathogen-associated molecular patterns and reacting to these through activation of the proinflammatory cytokines IL-1β and IL-18. In this study, we characterized the expression of inflammasome components in psoriatic skin and other common inflammatory skin diseases. Human skin biopsy specimens, cultured primary human keratinocytes, and peripheral blood mononuclear cells (PBMCs) were analyzed using quantitative reverse transcriptase-PCR (RT-PCR) and semiquantitative western blotting. mRNA expression of the inflammasome components NALP1, NALP3, ASC, caspase-1, caspase-4, and caspase-5 was detected in psoriatic skin. Interestingly, we found an extensive, 20-fold upregulation (P<0.01) of caspase-5 mRNA in lesional compared with nonlesional psoriatic skin, whereas caspase-1, caspase-4, and ASC (apoptosis-associated speck-like protein with CARD domain) mRNAs were upregulated by only 1.5- to 2.6-fold (P<0.01). Caspase-5 mRNA was not increased in biopsies from other inflammatory skin diseases, suggesting that this finding could be psoriasis specific. In vitro experiments revealed that caspase-5 mRNA was induced in primary keratinocytes as well as PBMCs stimulated with IFN-γ. Inhibition studies suggested that caspase-5 mRNA upregulation was mediated through the NF-κB pathway. Our findings suggest that caspase-5 and the inflammasome may have an important role in the inflammatory response in psoriasis. [ABSTRACT FROM AUTHOR]

Mitogen-activated protein kinase (MAPK) AP kinase 2 (MK2) is a serine/threonine kinase that is phosphorylated and activated by p38 MAPK. MK2 regulates the expression of various proinflammatory cytokines including TNF-α, IL-1β, IL-6, and IL-8. Recently, MK2 was demonstrated to be activated in lesional psoriatic epidermis. This study investigates for the first time the role of MK2 in skin inflammation using the model of oxazolone-induced acute allergic contact dermatitis in mice. We show that oxazolone treatment leads to increased expression and sustained activation of both p38 MAPK and MK2. The inflammatory response was determined by ear thickness, myeloperoxidase activity, and histology after oxazolone challenge. Pretreatment with the p38 MAPK inhibitor SB202190 and genetic ablation of MK2 inhibit this inflammatory response. In particular, IL-1β and, to a smaller but significant extent, also TNF-α and IFN-γ expression were decreased in MK2 knockout mice compared with wild-type mice. These results indicate that MK2 is a potential target for the treatment of inflammatory skin diseases.Journal of Investigative Dermatology (2009) 129, 891–898; doi:10.1038/jid.2008.322; published online 6 November 2008 [ABSTRACT FROM AUTHOR]

Altered miRNA expressions are assigned pathogenic properties in several cancers including mycosis fungoides (MF) and could play a role in the early onset of the disease. To examine disease specific miRNA expression in early-stage MF patch and plaque lesions. We used a qRT-PCR platform of 384 human miRNAs to study the miRNA expression in 154 diagnostic MF biopsies. One-hundred-and-ten miRNAs were significantly differentially expressed (>2-fold, P<0.05) between plaque lesions and healthy controls, and 90 miRNAs (>2-fold, P<0.05) differed between patch lesions and healthy controls. Moreover, 13 miRNAs differed in expression between patch and plaque lesions. Early-stage MF exhibited miRNA features overlapping with psoriasis. However, 39 miRNAs, including miR-142-3p, miR-150 and miR-146b, were MF specific. Early-stage MF express a distinct miRNA profile indicating that miRNAs play a role in the early development of MF. [ABSTRACT FROM AUTHOR]

Caspase-1 belongs to the group of inflammatory caspases and is the activating enzyme for the proinflammatory cytokine IL-18, a cytokine known to play an important role in the pathogenesis of psoriasis. The purpose of this study was to determine the expression of caspase-1 in psoriatic skin and the signaling mechanisms involved in stress-induced activation of caspase-1 and IL-18. Interestingly, increased caspase-1 activity in lesional compared with non-lesional psoriatic skin was seen. In vitro experiments in cultured human keratinocytes demonstrated anisomycin-induced, p38 mitogen-activated protein kinase (p38 MAPK)-dependent increased secretion of procaspase-1 and active caspase-1. Furthermore, anisomycin increased the mRNA expression of IL-18 through a p38 MAPK-dependent but caspase-1-independent mechanism, reaching a maximum level after 12 hours of stimulation. Finally, anisomycin caused a rapid (4 hours) increase in the secretion of proIL-18 and active IL-18. Secretion of active IL-18 was mediated through a p38 MAPK/caspase-1-dependent mechanism, whereas secretion of proIL-18 was mediated by a p38 MAPK-dependent but caspase-1-independent mechanism. These data demonstrate that the activity of caspase-1 is increased in psoriatic skin and that IL-18 secretion is regulated by a p38 MAPK/caspase-1-dependent mechanism, making caspase-1 a potential target in the treatment of psoriasis.Journal of Investigative Dermatology (2007) 127, 2857–2864; doi:10.1038/sj.jid.5700922; published online 28 June 2007 [ABSTRACT FROM AUTHOR]

The p38 mitogen-activated protein kinase (MAPK) signaling pathway, which regulates the activity of different transcriptions factors including NF-κB, is activated in lesional psoriatic skin. The purpose of this study was to investigate the effect of fumaric acid esters (FAEs) on the p38 MAPK and the downstream kinases mitogen- and stress-activated protein kinase (MSK)1 and 2 in cultured human keratinocytes. Cell cultures were incubated with dimethylfumarate (DMF), methylhydrogenfumarate (MHF), or fumaric acid (FA) and then stimulated with IL-1β before kinase activation was determined by Western blotting. A significant inhibition of both MSK1 and 2 activations was seen after preincubation with DMF and stimulation with IL-1β, whereas MHF and FA had no effect. In addition, DMF decreased phosphorylation of NF-κB/p65 (Ser276), which is known to be transactivated by MSK1. Furthermore, incubation with DMF before stimulation with IL-1β resulted in a significant decrease in NF-κB binding to the IL-8 κB and the IL-20 κB-binding sites as well as a subsequent decrease in IL-8 and IL-20 mRNA expression. Our results suggest that DMF specifically inhibits MSK1 and 2 activations and subsequently inhibits NF-κB-induced gene–transcriptions, which are believed to be important in the pathogenesis of psoriasis. These effects of DMF explain the anti-psoriatic effect of FAEs.Journal of Investigative Dermatology (2007) 127, 2129–2137; doi:10.1038/sj.jid.5700859; published online 10 May 2007 [ABSTRACT FROM AUTHOR]

The activity of the p38 mitogen-activated protein kinases (MAPKs) is increased in lesional psoriatic skin, supporting a possible role of these kinases in the pathogenesis of psoriasis. Recently, increased focal activation of the downstream target mitogen- and stress-activated protein kinase 1 (MSK1) was demonstrated in psoriatic epidermis. The purpose of this study is to investigate MSK2 and the transcription factor cyclic adenosine monophosphate response element-binding protein (CREB) in psoriatic skin and in cultured normal human keratinocytes. In lesional psoriatic skin, significantly increased MSK2 (Ser196) and CREB (Ser133) activation was demonstrated by phospho blotting. Immunofluorescence staining of phosphorylated MSK2 (Ser196) revealed colocalization with phosphorylated MSK1 (Thr 581) in the epidermis. Keratinocyte cultures stimulated with anisomycin and IL-1β showed increased MSK2 (Ser196) and CREB (Ser133) phosphorylation. Such activation was abolished during preincubation with a p38 inhibitor. Keratinocytes transfected with small interfering RNA showed a stronger decrease in CREB phosphorylation in MSK1/2 double-transfected cells than in MSK1 and MSK2 single-transfected cells. This study demonstrate for the first time the expression of MSK2 in keratinocytes and increased MSK2 and CREB activation in lesional psoriatic skin. Our results indicate that the p38-MAPK/MSK1/MSK2 and CREB signalling pathway may play a role in the pathogenesis of psoriasis.Journal of Investigative Dermatology (2007) 127, 2012–2019; doi:10.1038/sj.jid.5700821; published online 12 April 2007 [ABSTRACT FROM AUTHOR]

IL-20 is a novel member of the IL-10 cytokine family with pleiotropic effects. Current knowledge of what triggers and regulates IL-20 gene expression is sparse. The aim of this study was to investigate the regulation of IL-20 expression in cultured normal human keratinocytes. The expression of IL-20 was rapidly induced by proinflammatory stimuli, in particular IL-1β, IL-6, and UVB irradiation. Using kinase inhibitors and small-interfering RNA, we discovered that the p38 mitogen-activated protein kinase (MAPK) as well as inhibitory κB kinase -NF-κB signaling pathways are crucial for IL-20 expression. By electrophoretic mobility shift assay two κB-binding sites were identified upstream from the start codon in the IL-20 gene. Supershift analysis revealed binding of the p50/p65 heterodimer. Furthermore, the p38 MAPK was shown to exert its effects on IL-20 expression through activation of the downstream kinase mitogen- and stress-activated kinase 1 (MSK1), indicating transactivation of NF-κB driven IL-20 messenger RNA transcription as an important mechanism of action. IL-20 is assumed to be a key cytokine in the pathogenesis of psoriasis and possibly cancer, and therefore the p38 MAPK, MSK1, and NF-κB may be important new molecular targets for the modulation of IL-20 expression in these diseases.Journal of Investigative Dermatology (2007) 127, 1326–1336. doi:10.1038/sj.jid.5700713; published online 25 January 2007 [ABSTRACT FROM AUTHOR]

Mitogen- and stress-activated protein kinase 1 (MSK1) is a downstream target of both the p38 and extracellular signal-regulated kinase 1/2 (ERK1/2) mitogen-activated protein kinases (MAPKs). MSK1 stimulates transcription of different pro-inflammatory genes through activation of transcription factors. The purpose of this study was to investigate the expression and activation of MSK1 in lesional psoriatic skin and its role in cytokine production in cultured normal human keratinocytes. Western blotting revealed a consistent and significant increase in phosphorylated (activated) MSK1(Ser376) in lesional psoriatic skin. Immunofluorescence staining revealed the phosphorylated MSK1(Thr581) to be localized in the basal layers of the epidermis in lesional psoriatic skin. No staining was found in non-lesional psoriatic skin. Cultured human keratinocytes incubated with anisomycin or IL-1β resulted in the phosphorylation of the p38 MAPK and MSK1(Ser376). MSK1(Ser376) phosphorylation was inhibited by pre-incubation with the p38 inhibitor SB 202190. Transfection of the keratinocytes with specific MSK1 small interfering RNA resulted in 80% reduction of MSK1 expression and 51, 40, and 31% decrease in IL-6, IL-8, and tumor necrosis factor-α protein production, respectively. This study demonstrates for the first time the expression of MSK1 in epidermal keratinocytes and increased activation focally in psoriatic epidermis. As MSK1 regulates the production of pro-inflammatory cytokines, it may play a role in the pathogenesis of psoriasis.Journal of Investigative Dermatology (2006) 126, 1784–1791. doi:10.1038/sj.jid.5700252; published online 16 March 2006 [ABSTRACT FROM AUTHOR]

Nuclear factor-κB (NF-κB) is an inducible nuclear transcription factor regulating a range of cellular processes. An imbalance of the DNA binding activity of NF-κB may, therefore, be part of the pathophysiological mechanisms in psoriasis. The purpose of this study was to determine the NF-κB DNA binding activity in psoriatic skin using three differentκB sites and to determine how DNA binding activity was modulated by the anti-psoriatic drug calcipotriol. By electrophoretic mobility shift assay, we demonstrated that the NF-κB DNA binding to the p53κB site was decreased, whereas the NF-κB DNA binding to the interleukin-8 (IL-8)κB site was increased in lesional psoriatic skin compared with non-lesional psoriatic skin. No regulation was seen on the NF-κB DNA binding to the major histocompatibility complex class IκB site. These changes were paralleled by a similar decrease in p53 expression and an increase in IL-8 expression in involved psoriatic skin compared with uninvolved skin as determined by quantitative RT-PCR. The alteration in NF-κB DNA binding activity was neither accompanied by any change in the expression of the inhibitorκB (IκB) kinases, IKKα, IKKβ, and IKKγ nor in the expression of the NF-κB inhibitor proteins, IκBα and IκBβ. Immunofluorescence analysis revealed that p65 was sequestered in the cytoplasm of keratinocytes, whereas p50 exhibited a cytoplasmic as well as a nuclear localization. Interestingly, this distribution of p50 and p65 was similar in lesional and non-lesional psoriatic skin. Topical application of calcipotriol to lesional psoriatic skin for 4 d resulted in increased NF-κB binding to the p53κB site and decreased NF-κB binding to the IL-8κB site. Taken together, our data demonstrate that the NF-κB DNA binding activity is regulated in a specific manner in psoriatic skin depending on theκB sites investigated, and that topical treatment of psoriatic skin normalizes the abnormal NF-κB binding activity seen in lesional psoriatic skin. [ABSTRACT FROM AUTHOR]

Abnormal epidermal proliferation and differentiation characterize the inflammatory skin disease psoriasis. Here we demonstrate that expression of PPARδ mRNA and protein is markedly upregulated in psoriatic lesions and that lipoxygenase products accumulating in psoriatic lesions are potent activators of PPARδ. The expression levels of NF-κB p50 and p65 were not significantly altered in lesional compared with nonlesional psoriatic skin. In the basal layer of normal epidermis both p50 and p65 were sequestered in the cytoplasm, whereas p50, but not p65, localized to nuclei in the suprabasal layers, and this distribution was maintained in lesional psoriatic skin. In normal human keratinocytes PPAR agonists neither impaired IL-1β-induced translocation of p65 nor IL-1β-induced NF-κB DNA binding. We show that PPARδ physically interacts with the N-terminal Rel homology domain of p65. Irrespective of the presence of agonists none of the PPAR subtypes decreased p65-mediated transactivation in keratinocytes. In contrast p65, but not p50, was a potent repressor of PPAR-mediated transactivation. The p65-dependent repression of PPARδ- but not PPARα- or PPARγ-mediated transactivation was partially relieved by forced expression of the coactivators p300 or CBP. We suggest that deficient NF-κB activation in chronic psoriatic plaques permitting unabated PPARδ-mediated transactivation contributes to the pathologic phenotype of psoriasis. [ABSTRACT FROM AUTHOR]

Investigate the mechanism by which 1alpha,25-dihydroxyvitamin D[sub3] modulates activator protein 1 DNA binding activity in cultured normal human keratinocytes. Characteristics of stratified epidermis; Findings of western blotting and transfection experiments regarding dihydroxyvitamin; Effect of anti-annexin II antibody on the 1alpha,25(OH)[sub2]D[sub3]-induced phosphorylation.

Peroxisome proliferator-activated receptors (PPARs) are pleiotropic regulators of growth and differentiation of many cell types. We have performed a comprehensive analysis of the expression of PPARs, transcriptional cofactors, and marker genes during differentiation of normal human keratinocytes using a combination of reverse transcriptase polymerase chain reaction, Northern and Western blotting, and immunohistochemistry. PPARδ was the predominant PPAR subtype in human keratinocytes and highly expressed in basal cells and suprabasal cells. Induction of PPARα and PPARγ expression was linked to differentiation, and accordingly, expression of PPARα and PPARγ was in essence confined to suprabasal cells. Differentiation was not accompanied by significant changes in the expression of the coactivators CREB-binding protein, p300, steroid receptor coactivator 1, or the corepressors nuclear receptor corepressor and silence mediator for retinoid and thyroid hormone receptors. We critically evaluated the effects of selective PPAR ligands and a synthetic fatty acid analog, tetradecylthioacetic acid. Tetradecylthioacetic acid activated all human PPAR subtypes in the ranking order PPARδ >> PPARα > PPARγ. All selective PPAR ligands marginally induced transglutaminase-1 expression with the PPARδ-selective ligand L165041 being the most potent. The PPARα- and PPARγ-selective ligands Wy14643 and BRL49653 had negligible effect on involucrin expression, whereas a dose-dependent induction was observed with L165041. Simultaneous addition of L165041 and BRL49653 synergistically induced strong involucrin expression. Additionally, L165041 potently induced CD36 mRNA expression. Administration of tetradecylthioacetic acid resulted in a dramatic decrease in proliferation and a robust upregulation of the expression of involucrin and transglutaminase. Our results indicate that tetradecylthioacetic acid may affect keratinocyte gene... [ABSTRACT FROM AUTHOR]

Propositions about an abnormal fatty acid metabolism in atopic dermatitis patients prompted us to compare the phospholipid fatty acid composition and LTB4 release of neutropliils from 13 atopic dermatitis patients, as well as the adipose tissue triglyceride fatty acid composition, to that of 15 healthy controls matched by age, gender, and smoking habits. We found no differences in the tissue fatty acid composition between the two groups. The release of leukotrienc B4 from Ca-ionophore-stimulated neutrophils in patients was on the average only 42% (p <0.001) of that measured in the control group, despite the very similar arachidonic acid con- tents of these cells. Our study does not support the assumption of an abnormal fatty acid desaturation in atopic dermatitis patients. Rather, the capacity to release and/or convert arachidonic acid into leukotrienes in neutrophils appears to be affected by this disease. [ABSTRACT FROM AUTHOR]

Axial spondyloarthritis (axSpA), psoriatic arthritis (PsA), psoriasis, inflammatory bowel disease (IBD), and noninfectious uveitis form a distinct group among the immune mediated inflammatory diseases. Thus, many patients suffer from more than one of these disease manifestations. Here, we will use the term spondylitis-psoriasis-enthesitis-enterocolitis-dactylitis-uveitis-peripheral synovitis (SPEED-UP) spectrum disease. The aim is to review the new targeted pharmacological treatment options for all these diseases. All biological or targeted synthetic drugs with U.S. Food and Drug Administration (FDA) or European Medicines Agency (EMA) approval for any of the diagnoses axSpA, PsA, psoriasis, IBD, or non-infectious uveitis were included. Some of the drugs have documented efficacy in more than one of the diseases, e.g. tumor necrosis factor (TNF) inhibitors. However, other drugs are particularly effective for a specific inflamed tissue and approved in only one or two of the disease entities, e.g. abatacept for peripheral arthritis and vedolizumab for inflammatory bowel disease. This contributes with bedside to bench understanding of the immunology underlying this disease spectrum and provides clinicians with an overview that can assist stratified treatment decisions. We hope that this review will help guide clinicians to speed up treatment of patients with this disease spectrum. • Clinical trials with targeted drugs reveal immunopathogenic mechanisms. • Arthritis, psoriasis, enterocolitis, and uveitis often co-exist. • A stratified approach can speed up the time to effective treatment. [ABSTRACT FROM AUTHOR]

Methane (CH 4) is a potent greenhouse gas that is naturally produced and consumed in soil. The processes result in that soils may function as either a net sink or source of atmospheric methane. Although dry heath tundra ecosystems have recently been identified as important net sinks of atmospheric CH 4 , we understand little about how similar dry heath sites compare across both elevational gradients and wider geographical areas with regards to CH 4 fluxes. To address this shortcoming, we measured CH 4 fluxes and soil characteristics under ambient and experimental warming conditions at low and high elevation sites in South (61°N) and West (69°N) Greenland. We then used a structural equation model to explain CH 4 fluxes in relation to air temperatures and soil moisture. Soils across all sites were almost universal net CH 4 sinks (range for ambient plots: −1.2 to −3.9 μmol m−2 h−1). Observed soil CH 4 fluxes across all sites were significantly positively correlated to soil temperatures at 5 cm depth and negatively correlated to soil moisture. Additional factors such as soil pH and disturbance could also help to explain the differences in CH 4 fluxes between similar dry heath sites across greater spatial scales. Understanding the importance of these factors is likely critical to more accurately upscale plot-level measurements of CH 4 fluxes in constraining the terrestrial high latitude CH 4 sink. • The importance of soil characteristics on CH 4 uptake across dry heath ecosystems. • Higher CH 4 uptake in West vs. South Greenland despite of higher soil moisture. • CH 4 uptake predicted by combination of soil moisture and temperature. • Upscaling across wider landscapes challenged by variability in other soil factors. [ABSTRACT FROM AUTHOR]