12 research outputs found

    A Dietary Cholesterol-Based Intestinal Inflammation Assay for Improving Drug-Discovery on Inflammatory Bowel Diseases

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    Funding: This work was funded by the Fundação para a Ciência e a Tecnologia (FCT; PTDC/BTM-SAL/29377/2017 to CC and AJ. Zebrafish were reproduced and maintained by the CEDOC Fish Facility, supported by Congento LISBOA-01-0145- FEDER-022170, co-financed by FCT (Portugal) and Lisboa2020, under the PORTUGAL2020 agreement (European Regional Development Fund).Inflammatory bowel diseases (IBD) with chronic infiltration of immune cells in the gastrointestinal tract are common and largely incurable. The therapeutic targeting of IBD has been hampered by the complex causality of the disease, with environmental insults like cholesterol-enriched Western diets playing a critical role. To address this drug development challenge, we report an easy-to-handle dietary cholesterol-based in vivo assay that allows the screening of immune-modulatory therapeutics in transgenic zebrafish models. An improvement in the feeding strategy with high cholesterol diet (HCD) selectively induces a robust and consistent infiltration of myeloid cells in larvae intestines that is highly suitable for compound discovery efforts. Using transgenics with fluorescent reporter expression in neutrophils, we take advantage of the unique zebrafish larvae clarity to monitor an acute inflammatory response in a whole organism context with a fully functional innate immune system. The use of semi-automated image acquisition and processing combined with quantitative image analysis allows categorizing anti- or pro-inflammatory compounds based on a leukocytic inflammation index. Our HCD gut inflammation (HCD-GI) assay is simple, cost- and time-effective as well as highly physiological which makes it unique when compared to chemical-based zebrafish models of IBD. Besides, diet is a highly controlled, selective and targeted trigger of intestinal inflammation that avoids extra-intestinal outcomes and reduces the chances of chemical-induced toxicity during screenings. We show the validity of this assay for a screening platform by testing two dietary phenolic acids, namely gallic acid (GA; 3,4,5-trihydroxybenzoic acid) and ferulic acid (FA; 4-hydroxy-3-methoxycinnamic acid), with well described anti-inflammatory actions in animal models of IBD. Analysis of common IBD therapeutics (Prednisolone and Mesalamine) proved the fidelity of our IBD-like intestinal inflammation model. In conclusion, the HCD-GI assay can facilitate and accelerate drug discovery efforts on IBD, by identification of novel lead molecules with immune modulatory action on intestinal neutrophilic inflammation. This will serve as a jumping-off point for more profound analyses of drug mechanisms and pathways involved in early IBD immune responses.publishersversionpublishe

    Overview of beneficial effects of (Poly)phenol metabolites in the context of neurodegenerative diseases on model organisms

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    Funding Information: Funding: This work has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme under grant agreement No 804229. iNOVA4Health Research Unit (LISBOA—01–0145—FEDER—007344), which is cofunded by Fundação para a Ciência e Tecnologia (FCT)/Ministério da Ciência e do Ensino Superior, through national funds, and by FEDER under the PT2020 Partnership Agreement, is acknowledged. Authors Aβ—Amyloid beta; CAT—catalase; NF–κB—Nuclear factor kappa–light–chain–enhancer of activated B cell; GSK— Glycogen synthase kinase; GSH—glutathione; APP—Amyloid precursor protein; ROS—Reactive Oxygen Species; TNF— Tumor necrosis factor; JNK—c–Jun N–terminal kinases; SOD—Superoxide Dismutase; Tg—transgenic; PPAR— Peroxisome proliferator–activated receptor alpha; LPS—lipopolysaccharide; MPTP—1—methyl–4—phenyl–1,2,3,6— tetrahydropyridine. 1 (Poly)phenol metabolites are named accordingly the recommendations recently published [32], however the name cited in the original publications where the effect is described is indicated in brackets. ↑—increased ↓— decreased. Funding Information: would like to acknowledge FCT for financial support of D.C (2020.04630.BD), R.M (CEEC/04567/CBIOS/2020) and S.F (UIDP/BD4/04567/2020). Funding Information: This work has received funding from the European Research Council (ERC) under the European Union?s Horizon 2020 research and innovation programme under grant agreement No 804229. iNOVA4Health Research Unit (LISBOA?01?0145?FEDER?007344), which is cofunded by Funda??o para a Ci?ncia e Tecnologia (FCT)/Minist?rio da Ci?ncia e do Ensino Superior, through national funds, and by FEDER under the PT2020 Partnership Agreement, is acknowledged. Authors would like to acknowledge FCT for financial support of D.C (2020.04630.BD), R.M (CEEC/04567/CBIOS/2020) and S.F (UIDP/BD4/04567/2020). Publisher Copyright: © 2021 by the authors. Licensee MDPI, Basel, Switzerland.The rise of neurodegenerative diseases in an aging population is an increasing problem of health, social and economic consequences. Epidemiological and intervention studies have demonstrated that diets rich in (poly)phenols can have potent health benefits on cognitive decline and neurodegenerative diseases. Meanwhile, the role of gut microbiota is ever more evident in modulating the catabolism of (poly)phenols to dozens of low molecular weight (poly)phenol metabolites that have been identified in plasma and urine. These metabolites can reach circulation in higher concentrations than parent (poly)phenols and persist for longer periods of time. However, studies addressing their potential brain effects are still lacking. In this review, we will discuss different model organisms that have been used to study how low molecular weight (poly)phenol metabolites affect neuronal related mechanisms gathering critical insight on their potential to tackle the major hallmarks of neurodegeneration.publishersversionpublishe

    The Effect of ACTN3 and VDR Polymorphisms on Skeletal Muscle Performance in Axial Spondyloarthropathies

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    Funding Information: This study was supported by the funding through project MyoSpA, from iNOVA4 health. PM was supported by the National Institute for Health Research (NIHR) University College London Hospitals (UCLH) Biomedical Research Centre (BRC). Publisher Copyright: © Copyright © 2021 Pimenta, Mateus, Rodrigues-Manica, Pinheiro-Torres, Neto, Domingues, Lage Crespo, Sardoo, Machado, Branco, Silva and Pimentel-Santos.PBackground: Spondyloarthritis (SpA) are the most common group of chronic inflammatory rheumatic diseases affecting about 1.5% of the adult Caucasian population. Low back pain is the most common symptom. The aetiopathogenesis of SpA is multifactorial, with well-known genetic and environmental contributions. Furthermore, muscle properties might also be involved in the pathophysiological process and these could be modulated by the genetic background. Alpha-actinin-3 (ACTN3) and Vitamin D receptor (VDR) genes are well-known genes related with muscle performance. Our aim was to analyze four SNPs of these genes and to evaluate their influence in axial SpA (axSpA) susceptibility, phenotype and muscle properties. Methods: We performed a pilot study based on case-control approach involving 56 participants: 28 axSpA patients and 28 healthy controls matched by age, gender and levels of physical activity. Clinical, epidemiological and muscle characterization data—muscle physical properties (stiffness, tone, and elasticity), strength, mass, and performance, were collected. Two different muscles were considered for analysis, the Multifidus and Gastrocnemius. Four SNPs of ACTN3 (rs1815739) and VDR (rs2228570, rs731236, and rs7975232), were selected, analyzed and correlated with clinical, epidemiological and muscle characterization data. Results: In total, 51 individuals (27 axSpA patients and 24 matched controls) were eligible for further genetic analysis, 66.7% being male and with a mean age of 36 years. Muscle physical properties, muscle strength and muscle mass were similar in both groups; however, axSpA patients showed a decrease in muscle performance. None of the studied SNPs were associated with disease susceptibility/phenotype, muscle physical properties, muscle strength or muscle mass. However, ACTN3 rs1815739 and VDR rs2228570 were shown to be associated with muscle performance. Conclusion: Our results suggest an association between ACTN3 and VDR polymorphisms and muscle performance in axSpA.publishersversionpublishe

    The PAR Polarity Complex controls the directional migration of Medaka macrophages to sites of tissue injury in vivo

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    Registo Grau Estrangeiro Medicina (Universita Vita-Salute San Raffaele International, PhD School in Molecular Medicine, Italy). A dissertação em questão cumpre o disposto no nº2 do artº 11º da Portaria nº 29/2008 de 10 de janeiro (alterada pela Portaria nº 227/2017 de 20 de julho)ABSTRACT: The establishment and maintenance of cell polarity is fundamental for leukocyte responses to inflammatory cues. The evolutionary conserved partitioning defective (PAR) polarity complex consisting of PAR-3, PAR-6 and atypical protein kinase C (aPKC) temporally and spatially control polarization in a wide variety of cellular and organismal contexts. Apart from its classical role in polarized events such as asymmetric cell division, neuronal polarity and differentiation and epithelial apicalbasal polarity, the PAR complex has been revealed to play prominent functions during cell migration. Remarkably, to date there is no evidence that leukocytes use PAR signaling to polarize cell movement in a living organism. To investigate the physiological requirement of the PAR complex in leukocyte migration towards inflammatory cues in vivo, we used as model system membranetethered YFP (memYFP)-labeled medaka (Oryzias latipes) macrophages exposed to a mechanical wound in the larva tailfin1. To first identify signals that instigate macrophage recruitment to the injury, we evaluated the effect of pertussis toxin (PTX) in our wounding assay. As revealed by in vivo live imaging, the inhibition of Gαibounded G protein-coupled receptors (GPCRs) signaling impaired the directional movement of medaka macrophages migrating directionally towards the inflammatory site. We then adopted a transient transgenesis strategy in the transgenic (TG) line bearing memYFP fluorescent cells, to target the PAR complex activity or assembly selectively in macrophages and in a mosaic fashion using a battery of dominant interfering PAR complex mutants. By performing in vivo live imaging in the wounded larvae, we examined cell dynamic parameters in macrophages expressing each of the PAR complex-interfering mutants and in control cells. Compared to PKC-ζ-WT macrophages, the expression of either the dominant-negative PKC-ζ-KW or the constitutively active myristoylated (Myr)-PKC-ζ mutants decreased macrophage directional motility to the injured tailfin. The genetic displacement of PAR-6 or PAR- 3/aPKC interactions, induced by expressing selected PAR-3 and PAR-6 deletion mutants, also impaired wound-triggered macrophage directional motion, although the effects were comparatively less pronounced with respect to PKC-ζ mutants. In agreement with the PKC-ζ-KW phenotype, pharmacological inhibition of diacylglycerol 7 kinase (DGK), an upstream regulator of aPKCs signaling, reduced macrophage directional-speed and displacement towards damage. To visualize in detail the impact of the PAR complex in specific patterns of the cell cytoskeleton, we developed a double transgenic line amenable to the in vivo assessment of the dynamics of filamentous actin (F-actin) and the microtubule networks selectively in medaka macrophages. Preliminary analysis on high-resolution time-lapse image sequences provides evidence of an altered periodicity of F-actin front-rear waves and on microtubule-organizing center (MTOC) positioning in the perinuclear region of wound-activated macrophages interfered for the PAR complex activity or assembly. In addition, correlation studies revealed that each of the above perturbations negatively impacted wound-directed speed. Collectively, our findings reveal the existence of a functional role for core components of the PAR polarity complex in regulating the directional migration of myeloid cells responding to inflammation in vivo

    Muscle Evaluation in Axial Spondyloarthritis—The Evidence for Sarcopenia

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    Sarcopenia is a syndrome defined as a progressive and generalized skeletal muscle disorder associated with an increased likelihood of adverse outcomes such as falls, fractures, physical disability, and death. The actual definition of sarcopenia is based on a reduction in the values of three parameters: strength, muscle mass quantity or quality, and physical performance (the determinant of severity). Muscle wasting is a common feature in several chronic diseases, such as spondyloarthritis (SpA), and significantly increases patient morbidity and mortality. Although there has been huge progress in this field over recent years, the absence of a clear definition and clear diagnostic criteria of sarcopenia has resulted in inconsistent information regarding muscle-involvement in SpA. Thus, the aim of this review is to collect relevant evidence on muscular changes occurring during the disease process from the published literature, according to the recommended tools for sarcopenia evaluation proposed by the European Working Group on Sarcopenia in Older People 2 (EWGSOP2). In addition, data from histological, electromyography, and biochemical muscle analyses of SpA patients are also reviewed. Overall, a reduction in muscle strength with a systemic decrease in lean mass seems to be associated with a gait speed compromise. This information is usually fragmented, with no studies considering the three parameters together. This paper represents a call-to-action for the design of new studies in the future.publishersversionpublishe

    Perinuclear Arp2/3-driven actin polymerization enables nuclear deformation to facilitate cell migration through complex environments.

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    Cell migration has two opposite faces: although necessary for physiological processes such as immune responses, it can also have detrimental effects by enabling metastatic cells to invade new organs. In vivo, migration occurs in complex environments and often requires a high cellular deformability, a property limited by the cell nucleus. Here we show that dendritic cells, the sentinels of the immune system, possess a mechanism to pass through micrometric constrictions. This mechanism is based on a rapid Arp2/3-dependent actin nucleation around the nucleus that disrupts the nuclear lamina, the main structure limiting nuclear deformability. The cells' requirement for Arp2/3 to pass through constrictions can be relieved when nuclear stiffness is decreased by suppressing lamin A/C expression. We propose a new role for Arp2/3 in three-dimensional cell migration, allowing fast-moving cells such as leukocytes to rapidly and efficiently migrate through narrow gaps, a process probably important for their function

    Actin flows mediate a universal coupling between cell speed and cell persistence

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    Cell movement has essential functions in development, immunity, and cancer. Various cell migration patterns have been reported, but no general rule has emerged so far. Here, we show on the basis of experimental data in vitro and in vivo that cell persistence, which quantifies the straightness of trajectories, is robustly coupled to cell migration speed. We suggest that this universal coupling constitutes a generic law of cell migration, which originates in the advection of polarity cues by an actin cytoskeleton undergoing flows at the cellular scale. Our analysis relies on a theoretical model that we validate by measuring the persistence of cells upon modulation of actin flow speeds and upon optogenetic manipulation of the binding of an actin regulator to actin filaments. Beyond the quantitative prediction of the coupling, the model yields a generic phase diagram of cellular trajectories, which recapitulates the full range of observed migration patterns

    The Henna pigment Lawsone activates the Aryl Hydrocarbon Receptor and impacts skin homeostasis

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    As a first host barrier, the skin is constantly exposed to environmental insults that perturb its integrity. Tight regulation of skin homeostasis is largely controlled by the aryl hydrocarbon receptor (AhR). Here, we demonstrate that Henna and its major pigment, the naphthoquinone Lawsone activate AhR, both in vitro and in vivo. In human keratinocytes and epidermis equivalents, Lawsone exposure enhances the production of late epidermal proteins, impacts keratinocyte differentiation and proliferation, and regulates skin inflammation. To determine the potential use of Lawsone for therapeutic application, we harnessed human, murine and zebrafish models. In skin regeneration models, Lawsone interferes with physiological tissue regeneration and inhibits wound healing. Conversely, in a human acute dermatitis model, topical application of a Lawsone-containing cream ameliorates skin irritation. Altogether, our study reveals how a widely used natural plant pigment is sensed by the host receptor AhR, and how the physiopathological context determines beneficial and detrimental outcomes.publishersversionpublishe

    The MyoSpA Study Protocol

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    declArAtions ETHICS APPROVAL AND CONSENT TO PARTICIPATE The current study was submitted and approved by the ethical committee of University of Lisbon and Centro Hospitalar de Lisboa Ocidental, Hospital de Egas Moniz, EPE (Reference Number: 20170700050). The study will be conducted in accordance with the International Conference on Harmonization Good Clinical Practice (GCP) and the Declaration of Helsinki. Furthermore, voluntary written informed participants’ consent will be obtained from all subjects before the start of the study procedures. FUNDING This study was supported by iNOVA4Health (consortia to create a multidisdiplinary/translational network at the NOVA University, Lisbon, Portugal) and Portuguese Society of Rheumatology grants.BACKGROUND: Axial Spondyloarthritis (axSpA) is a chronic, inflammatory rheumatic disease that affects the axial skeleton, causing pain, stiffness, and fatigue. Genetics and environmental factors such as microbiota and microtrauma are known causes of disease susceptibility and progression. Murine models of axSpA found a decisive role for biomechanical stress as an inducer of enthesitis and new bone formation. Here, we hypothesize that muscle properties in axSpA patients are compromised and influenced by genetic background. OBJECTIVES: To improve our current knowledge of axSpA physiopathology, we aim to characterize axial and peripheral muscle properties and identify genetic and protein biomarker that might explain such properties. METHODS: A cross-sectional study will be conducted on 48 participants aged 18-50 years old, involving patients with axSpA (according to ASAS classification criteria, symptoms duration < 10 years) and healthy controls matched by gender, age, and levels of physical activity. We will collect epidemiological and clinical data and perform a detailed, whole body and segmental, myofascial characterization (focusing on multifidus, brachioradialis and the gastrocnemius lateralis) concerning: a) Physical Properties (stiffness, tone and elasticity), assessed by MyotonPRO®; b) Strength, by a dynamometer; c) Mass, by bioimpedance; d) Performance through gait speed and 60-second sit-to-stand test; e) Histological and cellular/ molecular characterization through ultrasound-guided biopsies of multifidus muscle; f) Magnetic Resonance Imaging (MRI) characterization of paravertebral muscles. Furthermore, we will perform an integrated transcriptomics and proteomics analysis of peripheral blood samples. DISCUSSION: The innovative and multidisciplinary approaches of this project rely on the elucidation of myofascial physical properties in axSpA and also on the establishment of a biological signature that relates to specific muscle properties. This hitherto unstudied link between gene/protein signatures and muscle properties may enhance our understanding of axSpA physiopathology and reveal new and useful diagnostic and therapeutic targets.publishersversionpublishe
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