Functional and Metabolic Characterization of Microglia Culture in a Defined Medium

Microglia are the endogenous immune cells of the brain and act as sensor of infection and pathologic injury to the brain, leading to a rapid plastic process of activation that culminates in the endocytosis and phagocytosis of damaged tissue. Microglia cells are the most plastic cells in the brain. Microglia isolation from their environment as well as culturing them in the presence of serum alter their function and lead to a rapid loss of their signature gene expression. Previous studies have identified pivotal factors allowing microglia culture in the absence of serum. Here, we have further characterized the function, expression of markers, metabolic status and response to pro and anti-inflammatory stimulus of microglia isolated by magnetic-activated cell sorting and cultured in a chemically defined medium. We have compared this new method with previous traditional protocols of culturing microglia that use high concentrations of serum.This work was supported by the Spanish Ministry of Education and Science (SAF2013-45084-R and SAF2016-75292-R, including a fellowship to AM), the University of the Basque Country (UPV/EHU; fellowship to AZ), and Centro de Investigacion Biomedica en Red, Enfermedades Neurodegenerativas (CIBERNED) (grant no. CB06/05/0076)

Contribution of P2X4 Receptors to CNS Function and Pathophysiology

The release and extracellular action of ATP are a widespread mechanism for cell-to-cell communication in living organisms through activation of P2X and P2Y receptors expressed at the cell surface of most tissues, including the nervous system. Among ionototropic receptors, P2X4 receptors have emerged in the last decade as a potential target for CNS disorders such as epilepsy, ischemia, chronic pain, anxiety, multiple sclerosis and neurodegenerative diseases. However, the role of P2X4 receptor in each pathology ranges from beneficial to detrimental, although the mechanisms are still mostly unknown. P2X4 is expressed at low levels in CNS cells including neurons and glial cells. In normal conditions, P2X4 activation contributes to synaptic transmission and synaptic plasticity. Importantly, one of the genes present in the transcriptional program of myeloid cell activation is P2X4. Microglial P2X4 upregulation, the P2X4+ state of microglia, seems to be common in most acute and chronic neurodegenerative diseases associated with inflammation. In this review, we summarize knowledge about the role of P2X4 receptors in the CNS physiology and discuss potential pitfalls and open questions about the therapeutic potential of blocking or potentiation of P2X4 for different pathologies.The authors work are supported by grants from Merck Serono (a business of Merck KGaA, Darmstadt, Germany), Spanish Ministry of Education and Science (SAF2016-75292-R and PID2019-109724RB-I00), Basque Government (IT1203/19 and PI-2016-1-0016) and Centro de Investigación Biomédica en Red en Enfermedades Neurodegenerativas (CIBERNED)

Role of Mitochondrial Dynamics in Microglial Activation and Metabolic Switch

Microglia act as sensors of injury in the brain, favoring its homeostasis. Their activation and polarization toward a proinflammatory phenotype are associated with injury and disease. These processes are linked to a metabolic reprogramming of the cells, characterized by high rates of glycolysis and suppressed oxidative phosphorylation. This metabolic switch can be reproduced in vitro by microglial stimulation with LPS plus IFN-gamma. To understand the mechanisms regulating mitochondrial respiration abolishment, we examined potential alterations in mitochondrial features during this switch using rat primary microglia. Cells did not show any change in mitochondrial membrane potential, suggesting a limited impact in the mitochondrial viability. We provide evidence that reverse operation of F0F1-ATP synthase contributes to mitochondrial membrane potential. In addition, we studied the possible implication of mitochondrial dynamics in the metabolic switch using the mitochondrial division inhibitor-1 (Mdivi-1), which blocks dynamin-related protein 1 (Drp1)-dependent mitochondrial fission. Mdivi-1 significantly reduced the expression of proinflammatory markers in LPS plus IFN-gamma-treated microglia. However, this inhibition did not lead to a recovery of the oxidative phosphorylation ablation by LPS plus IFN-gamma or to a microglia repolarization. Altogether, these results suggest that Drp1-dependent mitochondrial fission, although potentially involved in microglial activation, does not play an essential role in metabolic reprogramming and repolarization of microglia

Clemastine Induces an Impairment in Developmental Myelination

[EN] Abnormalities in myelination are associated to behavioral and cognitive dysfunction in neurodevelopmental psychiatric disorders. Thus, therapies to promote or accelerate myelination could potentially ameliorate symptoms in autism. Clemastine, a histamine H1 antagonist with anticholinergic properties against muscarinic M1 receptor, is the most promising drug with promyelinating properties. Clemastine penetrates the blood brain barrier efficiently and promotes remyelination in different animal models of neurodegeneration including multiple sclerosis, ischemia and Alzheimer's disease. However, its role in myelination during development is unknown. We showed that clemastine treatment during development increased oligodendrocyte differentiation in both white and gray matter. However, despite the increase in the number of oligodendrocytes, conduction velocity of myelinated fibers of corpus callosum decreased in clemastine treated mice. Confocal and electron microscopy showed a reduction in the number of myelinated axons and nodes of Ranvier and a reduction of myelin thickness in corpus callosum. To understand the mechanisms leading to myelin formation impairment in the presence of an excess of myelinating oligodendrocytes, we focused on microglial cells that also express muscarinic M1 receptors. Importantly, the population of CD11c(+) microglia cells, necessary for myelination, as well as the levels of insulin growth factor-1 decrease in clemastine-treated mice. Altogether, these data suggest that clemastine impact on myelin development is more complex than previously thought and could be dependent on microglia-oligodendrocyte crosstalk. Further studies are needed to clarify the role of microglia cells on developmental myelination.This work was supported by Spanish Ministry of Education and Science (SAF 2016-75292- R); Spanish Ministry of Science andInnovation (PID 2019-109724RB-I00); Basque Government (PI-2016-1-0016); the University of the Basque Country (UPV/EHU);and Centro de Investigacion Biomedica en Red, EnfermedadesNeurodegenerativas (CIBERNED; grant CB06/05/0076). AP hasa predoctoral fellowship from the University of the Basque Country (UPV/EHU), AM has a predoctoral fellowship fromthe Spanish Ministry of Education and Science and AO-de-A hasa postdoctoral fellowship from the Basque Governmen

Complement component 3 as biomarker of disease activity and cardiometabolic risk factor in rheumatoid arthritis and spondyloarthritis.

Funder: Europeo de Desarrollo Regional de la Unión EuropeaFunder: Rheumatic Diseases NetworkOBJECTIVE: To analyze the relationship between complement component 3 (C3) and the prevalence of cardiometabolic risk factors and disease activity in the rheumatic diseases having the highest rates of cardiovascular morbidity and mortality: rheumatoid arthritis (RA), psoriatic arthritis (PsA) and axial spondyloarthritis (axSpA). METHODS: This is a cross-sectional study including 200 RA, 80 PsA, 150 axSpA patients and 100 healthy donors. The prevalence of cardiometabolic risk factors [obesity, insulin resistance, type 2 diabetes mellitus, hyperlipidemia, apolipoprotein B/apolipoprotein A (apoB/apoA) and atherogenic risks and hypertension] was analyzed. Serum complement C3 levels, inflammatory markers and disease activity were evaluated. Cluster analysis was performed to identify different phenotypes. Receiver operating characteristic (ROC) curve analysis to assess the accuracy of complement C3 as biomarker of insulin resistance and disease activity was carried out. RESULTS: Levels of complement C3, significantly elevated in RA, axSpA and PsA patients, were associated with the prevalence of cardiometabolic risk factors. Hard clustering analysis identified two distinctive phenotypes of patients depending on the complement C3 levels and insulin sensitivity state. Patients from cluster 1, characterized by high levels of complement C3 displayed increased prevalence of cardiometabolic risk factors and high disease activity. ROC curve analysis showed that non-obesity related complement C3 levels allowed to identify insulin resistant patients. CONCLUSIONS: Complement C3 is associated with the concomitant increased prevalence of cardiometabolic risk factors in rheumatoid arthritis and spondyloarthritis. Thus, complement C3 should be considered a useful marker of insulin resistance and disease activity in these rheumatic disorders

Effects of Platelet-Rich Plasma on Cellular Populations of the Central Nervous System: The Influence of Donor Age

first_page settings Open AccessArticle Effects of Platelet-Rich Plasma on Cellular Populations of the Central Nervous System: The Influence of Donor Age by Diego Delgado 1, Ane Miren Bilbao 2, Maider Beitia 1, Ane Garate 1, Pello Sánchez 1, Imanol González-Burguera 3,4, Amaia Isasti 4,5, Maider López De Jesús 4,5,6, Jone Zuazo-Ibarra 7, Alejandro Montilla 7 [OrcID] , María Domercq 7 [OrcID] , Estibaliz Capetillo-Zarate 7,8, Gontzal García del Caño 3,4 [OrcID] , Joan Sallés 4,5,6, Carlos Matute 7 and Mikel Sánchez 1,2,* 1 Advanced Biological Therapy Unit, Hospital Vithas Vitoria, 01008 Vitoria-Gasteiz, Spain 2 Arthroscopic Surgery Unit, Hospital Vithas Vitoria, 01008 Vitoria-Gasteiz, Spain 3 Department of Neurosciences, Faculty of Pharmacy, University of the Basque Country (UPV/EHU), 01008 Vitoria-Gasteiz, Spain 4 Bioaraba, Neurofarmacología Celular y Molecular, 01008 Vitoria-Gasteiz, Spain 5 Department of Pharmacology, Faculty of Pharmacy, University of the Basque Country (UPV/EHU), 01008 Vitoria-Gasteiz, Spain 6 Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), 28029 Madrid, Spain 7 Achucarro Basque Center for Neuroscience, CIBERNED and Departamento de Neurociencias, Universidad del País Vasco (UPV/EHU), 48940 Leioa, Spain 8 IKERBASQUE, Basque Foundation for Science, 48009 Bilbao, Spain * Author to whom correspondence should be addressed. Academic Editor: Francesca Santilli Int. J. Mol. Sci. 2021, 22(4), 1725; https://doi.org/10.3390/ijms22041725 Received: 24 November 2020 / Revised: 12 January 2021 / Accepted: 3 February 2021 / Published: 9 February 2021 (This article belongs to the Section Molecular Endocrinology and Metabolism) Download PDF Browse Figures Citation Export Abstract Platelet-rich plasma (PRP) is a biologic therapy that promotes healing responses across multiple medical fields, including the central nervous system (CNS). The efficacy of this therapy depends on several factors such as the donor’s health status and age. This work aims to prove the effect of PRP on cellular models of the CNS, considering the differences between PRP from young and elderly donors. Two different PRP pools were prepared from donors 65–85 and 20–25 years old. The cellular and molecular composition of both PRPs were analyzed. Subsequently, the cellular response was evaluated in CNS in vitro models, studying proliferation, neurogenesis, synaptogenesis, and inflammation. While no differences in the cellular composition of PRPs were found, the molecular composition of the Young PRP showed lower levels of inflammatory molecules such as CCL-11, as well as the presence of other factors not found in Aged PRP (GDF-11). Although both PRPs had effects in terms of reducing neural progenitor cell apoptosis, stabilizing neuronal synapses, and decreasing inflammation in the microglia, the effect of the Young PRP was more pronounced. In conclusion, the molecular composition of the PRP, conditioned by the age of the donors, affects the magnitude of the biological response.This work was funded by the Provincial Council of Alava through the AlavaInnova Program, Basque Government through the GAITEK Program, Ministry of Economy, Industry and Competitiveness (CTQ2017-85686-R), Spanish Ministry of Education and Science (PID2019-109724RB-I00), Basque Government (IT1203-19, IT1230-19, and KK-2020/00034) and Centro de Investigación Biomédica en Red en Enfermedades Neurodegenerativas (CIBERNED)

The clinical and molecular cardiometabolic fingerprint of an exploratory psoriatic arthritis cohort is associated with the disease activity and differentially modulated by methotrexate and apremilast

Objectives: (1) To evaluate clinical and molecular cardiovascular disease (CVD) signs and their relationship with psoriatic arthritis (PsA) features and (2) to identify a clinical patient profile susceptible to benefit from methotrexate (MTX) and/or apremilast regarding CVD risk. Methods: This cross-sectional study included 100 patients with PsA and 100 age-matched healthy donors. In addition, an exploratory cohort of 45 biologically naïve patients treated for 6 months with apremilast, MTX or combined therapy according to routine clinical practice was recruited. Extensive clinical and metabolic profiles were obtained. Ninety-nine surrogate CVD-related molecules were analysed in plasma and peripheral blood mononuclear cells (PBMCs). Hard cluster analysis was performed to identify the clinical and molecular phenotypes. Mechanistic studies were performed on adipocytes. Results: Cardiometabolic comorbidities were associated with disease activity and long-term inflammatory status. Thirty-five CVD-related proteins were altered in the plasma and PBMCs of PsA patients and were associated with the key clinical features of the disease. Plasma levels of some of the CVD-related molecules might distinguish insulin-resistant patients (MMP-3, CD163, FABP-4), high disease activity (GAL-3 and FABP-4) and poor therapy outcomes (CD-163, LTBR and CNTN-1). Hard cluster analysis identified two phenotypes of patients according to the rates of cardiometabolic comorbidities with distinctive clinical and molecular responses to each treatment. Conclusions: (1) Novel CVD-related proteins associated with clinical features could be emerging therapeutic targets in the context of PsA and (2) the pleiotropic action of apremilast could make it an excellent choice for the management of PsA patients with high CVD risk, targeting metabolic alterations and CVD-related molecules

In vivo multimodal imaging of adenosine A1 receptors in neuroinflammation after experimental stroke

Adenosine A(l) receptors (A(l)ARs) are promising imaging biomarkers and targets for the treatment of stroke. Nevertheless, the role of A(l)ARs on ischemic damage and its subsequent neuroinflammatory response has been scarcely explored so far. Methods: In this study, the expression of A(1)ARs after transient middle cerebral artery occlusion (MCAO) was evaluated by positron emission tomography (PET) with [F-18]CPFPX and immunohistochemistry (IHC). In addition, the role of AIARs on stroke inflammation using pharmacological modulation was assessed with magnetic resonance imaging (MRI), PET imaging with [F-18]DPA-714 (TSPO) and [F-18]FLT (cellular proliferation), as well as IHC and neurofunctional studies. Results: In the ischemic territory, [F-18]CPFPX signal and IHC showed the overexpression of A(l)ARs in microglia and infiltrated leukocytes after cerebral ischemia. Ischemic rats treated with the AAR agonist ENBA showed a significant decrease in both [F-18]DPA-714 and [F-18]FLT signal intensities at day 7 after cerebral ischemia, a feature that was confirmed by IHC results. Besides, the activation of A(l)AR promoted the reduction of the brain lesion, as measured with T2W-MRI, and the improvement of neurological outcome including motor, sensory and reflex responses. These results show for the first time the in vivo PET imaging of A(l)AR expression after cerebral ischemia in rats and the application of [F-18]FLT to evaluate glial proliferation in response to treatment. Conclusion: Notably, these data provide evidence for A(l)AR playing a key role in the control of both the activation of resident glia and the de novo proliferation of microglia and macrophages after experimental stroke in rats.The authors would like to thank A. Leukona and V. Salinas for technical support in the radiosynthesis. This study was funded by grants from the Spanish Ministry of Education and Science/FEDER RYC-201722412, SAF2016-75292-R, SAF2017-87670-R and PID2019-107989RB-I00, the Basque Government (IT1203/19, BIO18/IC/006) and CIBERNED. Maria Ardaya holds a fellowship from the University of Pais Vasco. Ana Joya acknowledges funding from Fundacio La Marato de TV3 (17/C/2017). Juan Jose Gutierrez acknowledges funding from Euskampus Fundazioa. Jordi Llop also acknowledges The Spanish Ministry of Economy and Competitiveness (Grant CTQ2017-87637-R). Part of the work has been performed under the Maria de Maeztu Units of Excellence Program from the Spanish State Research Agency (Grant No. MDM-2017-0720)

Incidence, associated factors and clinical impact of severe infections in a large, multicentric cohort of patients with systemic lupus erythematosus

OBJECTIVES: To estimate the incidence of severe infection and investigate the associated factors and clinical impact in a large systemic lupus erythematosus (SLE) retrospective cohort. METHODS: All patients in the Spanish Rheumatology Society Lupus Registry (RELESSER) who meet ?4 ACR-97 SLE criteria were retrospectively investigated for severe infections. Patients with and without infections were compared in terms of SLE severity, damage, comorbidities, and demographic characteristics. A multivariable Cox regression model was built to calculate hazard ratios (HRs) for the first infection. RESULTS: A total of 3658 SLE patients were included: 90% female, median age 32.9 years (DQ 9.7), and mean follow-up (months) 120.2 (±87.6). A total of 705 (19.3%) patients suffered ?1 severe infection. Total severe infections recorded in these patients numbered 1227. The incidence rate was 29.2 (95% CI: 27.6-30.9) infections per 1000 patient years. Time from first infection to second infection was significantly shorter than time from diagnosis to first infection (p < 0.000). Although respiratory infections were the most common (35.5%), bloodstream infections were the most frequent cause of mortality by infection (42.0%). In the Cox regression analysis, the following were all associated with infection: age at diagnosis (HR = 1.016, 95% CI: 1.009-1.023), Latin-American (Amerindian-Mestizo) ethnicity (HR = 2.151, 95% CI: 1.539-3.005), corticosteroids (?10mg/day) (HR = 1.271, 95% CI: 1.034-1.561), immunosuppressors (HR = 1.348, 95% CI: 1.079-1.684), hospitalization by SLE (HR = 2.567, 95% CI: 1.905-3.459), Katz severity index (HR = 1.160, 95% CI: 1.105-1.217), SLICC/ACR damage index (HR = 1.069, 95% CI: 1.031-1.108), and smoking (HR = 1.332, 95% CI: 1.121-1.583). Duration of antimalarial use (months) proved protective (HR = 0.998, 95% CI: 0.997-0.999). CONCLUSIONS: Severe infection constitutes a predictor of poor prognosis in SLE patients, is more common in Latin-Americans and is associated with age, previous infection, and smoking. Antimalarials exerted a protective effect.Spanish Foundation of Rheumatology. FIS/ISCIII (grant number PI11/02857). Dr. Pego-Reigosa is supported by Grant 316265 (BIOCAPS) from the European Union 7th Framework Programme (FP7/REGPOT-2012–2013.1)

Comprehensive description of clinical characteristics of a large systemic Lupus Erythematosus Cohort from the Spanish Rheumatology Society Lupus Registry (RELESSER) with emphasis on complete versus incomplete lupus differences

Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by multiple organ involvement and pronounced racial and ethnic heterogeneity. The aims of the present work were (1) to describe the cumulative clinical characteristics of those patients included in the Spanish Rheumatology Society SLE Registry (RELESSER), focusing on the differences between patients who fulfilled the 1997 ACR-SLE criteria versus those with less than 4 criteria (hereafter designated as incomplete SLE (iSLE)) and (2) to compare SLE patient characteristics with those documented in other multicentric SLE registries. RELESSER is a multicenter hospital-based registry, with a collection of data from a large, representative sample of adult patients with SLE (1997 ACR criteria) seen at Spanish rheumatology departments. The registry includes demographic data, comprehensive descriptions of clinical manifestations, as well as information about disease activity and severity, cumulative damage, comorbidities, treatments and mortality, using variables with highly standardized definitions. A total of 4.024 SLE patients (91% with ≥4 ACR criteria) were included. Ninety percent were women with a mean age at diagnosis of 35.4 years and a median duration of disease of 11.0 years. As expected, most SLE manifestations were more frequent in SLE patients than in iSLE ones and every one of the ACR criteria was also associated with SLE condition; this was particularly true of malar rash, oral ulcers and renal disorder. The analysis-adjusted by gender, age at diagnosis, and disease duration-revealed that higher disease activity, damage and SLE severity index are associated with SLE [OR: 1.14; 95% CI: 1.08-1.20 (P < 0.001); 1.29; 95% CI: 1.15-1.44 (P < 0.001); and 2.10; 95% CI: 1.83-2.42 (P < 0.001), respectively]. These results support the hypothesis that iSLE behaves as a relative stable and mild disease. SLE patients from the RELESSER register do not appear to differ substantially from other Caucasian populations and although activity [median SELENA-SLEDA: 2 (IQ: 0-4)], damage [median SLICC/ACR/DI: 1 (IQ: 0-2)], and severity [median KATZ index: 2 (IQ: 1-3)] scores were low, 1 of every 4 deaths was due to SLE activity. RELESSER represents the largest European SLE registry established to date, providing comprehensive, reliable and updated information on SLE in the southern European population