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22 p.-3 fig.-3 tab. Antonell, Anna et al. ; Alzheimer's disease (AD) is the most common of the neurodegenerative diseases. Recent diagnostic criteria have defined a preclinical disease phase during which neuropathological substrates are thought to be present in the brain. There is an urgent need to find measurable alterations in this phase as well as a good peripheral biomarker in the blood. We selected a cohort of 100 subjects (controls = 47; preclinical AD = 11; patients with AD = 42) and analyzed whole blood expression of 20 genes by quantitative polymerase chain reaction. The selected genes belonged to calcium-signaling, senescence and autophagy, and mitochondria/oxidative stress pathways. Additionally, two genes associated with an increased risk of developing AD (CLU and BIN1) were also analyzed. We detected significantly different gene expressions of BECN1 and PRKCB between the control and the AD groups; and, of CDKN2A between the control and the preclinical AD groups. Notably, these three genes are also considered tumor suppressor (CDKN2A and BECN1) or tumor promoter (PRKCB) genes. Gene-gene expression Pearson correlations were computed separately for controls and patients with AD. The significant correlations (p<0.001) were represented in a network analysis with Cytoscape tool, which suggested an uncoupling of mitochondriarelated genes in AD group. Whole blood is emerging as a valuable tissue in the study of the physiopathology of AD. ; This study was supported by grants to JLM (Consolider CSD2010-00045) and to ALL (PI14/00282, ISCIII, Cofinancia FEDER, Unión Europea, Otra manera de hacer Europa) from the Spanish Ministry of Economy and Competitiveness. The research leading to these results has received support from the Innovative Medicines Initiative Joint Undertaking under grant agreement n°115568, resources of which are composed of financial contribution from the European Union's Seventh Framework Programme (FP7/2007-2013) and EFPIA companies' in kind contribution. ; Peer reviewed

El pdf del artículo es la versión pre-print.-- et al. ; Alzheimer's disease (AD) is a devastating age-related neurodegenerative disease. Age is the main risk factor for sporadic AD, which is the most prevalent type. Amyloid-β peptide (Aβ) neurotoxicity is the proposed first step in a cascade of deleterious events leading to AD pathology and dementia. Glial cells play an important role in these changes. Astrocytes provide vital support to neurons and modulate functional synapses. Therefore, the toxic effects of Aβ on astrocytes might promote neurodegenerative changes that lead to AD. Aging reduces astrocyte antioxidant defenses and induces oxidative stress. We studied the effects of Aβ {42} on cultures of human astrocytes in the presence or absence of the following pro-oxidant agents: buthionine sulfoximine (BSO), a glutathione synthesis inhibitor, and FeSO{4}, which liberates redox active iron. Pro-oxidant conditions potentiated Aβ toxicity, as shown by the generation of free radicals, inflammatory changes, and apoptosis. Similar treatments were assessed in rats in vivo. A combination of Aβ {40} and Aβ {42} or Aβ {42} alone was infused intracerebroventricularly for 4 weeks. Other animal groups were also infused with BSO and FeSO{4}. A long-term analysis that ended 4 months later showed greater cognitive impairment in the Morris water maze task, which was induced by Aβ plus pro-oxidant agent treatments. Pro-oxidant agents also potentiated brain tissue pathology. This was demonstrated in histological studies that showed highly increased astrocyte reactivity in AD-vulnerable areas, Aβ deposits, and oxidative damage of AD-sensitive hippocampal neurons. To increase our understanding of AD, experimental models should be used that mimic age-related brain changes, in which age-related oxidative stress potentiates the effects of Aβ. © 2010 - IOS Press and the authors. ; This study was supported by grants SAF200613092-C02-02 from the Spanish Ministerio de Ciencia e Innovación, RD06/0013/1004 (RETICEF) from the Instituto de Salud Carlos III, 062931 from Fundació La Marató de TV3 and by the European Network of Excellence DiMI (LSHB-CT-2005-512146). S. García-Matas received a Generalitat (Autonomous Government of Catalonia) fellowship. ; Peer Reviewed

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by a severe and progressive neuronal loss leading to cognitive dysfunctions. Previous reports, based on the use of chemical inhibitors, have connected the stress kinase p38α to neuroinflammation, neuronal death and synaptic dysfunction. To explore the specific role of neuronal p38α signalling in the appearance of pathological symptoms, we have generated mice that combine expression of the 5XFAD transgenes to induce AD symptoms with the downregulation of p38α only in neurons (5XFAD/p38α-N). We found that the neuronal-specific deletion of p38α improves the memory loss and long-term potentiation impairment induced by 5XFAD transgenes. Furthermore, 5XFAD/p38α-N mice display reduced amyloid-β accumulation, improved neurogenesis, and important changes in brain cytokine expression compared with 5XFAD mice. Our results implicate neuronal p38α signalling in the synaptic plasticity dysfunction and memory impairment observed in 5XFAD mice, by regulating both amyloid-β deposition in the brain and the relay of this accumulation to mount an inflammatory response, which leads to the cognitive deficits. ; Spanish Ministerio de Economia y Competitividad (MINECO). S.C. was partly supported by the European Union Seventh Framework Programme (FP7/Marie Curie Actions/COFUND). IRB Barcelona is the recipient of a Severo Ochoa Award of Excellence from MINECO (Government of Spain) ; Peer Reviewed

Neuroinflammation is a risk factor for Alzheimer's disease (AD). We sought to study the glial derangement in AD using diverse experimental models and human brain tissue. Besides classical pro-inflammatory cytokines, we analyzed chitinase 3 like 1 (CHI3L1 or YKL40) and triggering receptor expressed on myeloid cells 2 (TREM2) that are increasingly being associated with astrogliosis and microgliosis in AD, respectively. The SAMP8 mouse model of accelerated aging and AD traits showed elevated pro-inflammatory cytokines and activated microglia phenotype. Furthermore, 6-month-old SAMP8 showed an exacerbated inflammatory response to peripheral lipopolysaccharide in the hippocampus and null responsiveness at the advanced age (for this strain) of 12 months. ; This research was funded by Spanish MINECO and European Regional Development Fund, grant number SAF2016- 77703; Spanish MCINN, grant number PID2019-106285RB; Catalan Autonomous Government AGAUR, grant number 2017-SGR-106; Competitiveness Operational Programme 2014-2020, C-Reactive protein therapy for stroke-associated dementia, ID P_37_674, MySMIS code: 103432, contract 51/05.09.2016; and the CERCA Programme/Generalitat de Catalunya. RCo was supported by a post-doctoral research contract of the Centro de Investigación Biomédica en Red de Epidemiología y Salud Pública (CIBERESP), Instituto de Salud Carlos III, Madrid, Spain. AL (PERIS SLT008/18/00061) received funding from Departament de Salut de la Generalitat de Catalunya. We acknowledge support of the publication fee by the CSIC Open Access Publication Support Initiative through its Unit of Information Resources for Research (URICI).

Geroprotectors, a class of drugs targeting multiple deficits occurring with age, necessitate the development of new animal models to test their efficacy. The COST Action MouseAGE is a European network whose aim is to reach consensus on the translational path required for geroprotectors, interventions targeting the biology of ageing. In our previous work we identified frailty and loss of resilience as a potential target for geroprotectors. Frailty is the result of an accumulation of deficits, which occurs with age and reduces the ability to respond to adverse events (physical resilience). Modelling frailty and physical resilience in mice is challenging for many reasons. There is no consensus on the precise definition of frailty and resilience in patients or on how best to measure it. This makes it difficult to evaluate available mouse models. In addition, the characterization of those models is poor. Here we review potential models of physical resilience, focusing on those where there is some evidence that the administration of acute stressors requires integrative responses involving multiple tissues and where aged mice showed a delayed recovery or a worse outcome then young mice in response to the stressor. These models include sepsis, trauma, drug- and radiation exposure, kidney and brain ischemia, exposure to noise, heat and cold shock. ; This article is based upon work from COST Action (BM1402: MouseAGE), supported by COST (European Cooperation in Science and Technology) and European Union Research and Innovation Program Horizon 2020 (GrantAgreement Number 730879). This work was supported by the Austrian Research Fund (FWF: P30623-B26), the Spanish MINECO (SAF2016-77703), the European Regional Development Fund, and the MRC-Arthritis Research UK Centre for Integrated Research into Musculoskeletal Ageing. ; Peer reviewed

Monomeric C-reactive protein (mCRP), the activated isoform of CRP, induces tissue damage in a range of inflammatory pathologies. Its detection in infarcted human brain tissue and its experimentally proven ability to promote dementia with Alzheimer's disease (AD) traits at 4 weeks after intrahippocampal injection in mice have suggested that it may contribute to the development of AD after cerebrovascular injury. Here, we showed that a single hippocampal administration of mCRP in mice induced memory loss, lasting at least 6 months, along with neurodegenerative changes detected by increased levels of hyperphosphorylated tau protein and a decrease of the neuroplasticity marker Egr1. Furthermore, co-treatment with the monoclonal antibody 8C10 specific for mCRP showed that long-term memory loss and tau pathology were entirely avoided by early blockade of mCRP. Notably, 8C10 mitigated Egr1 decrease in the mouse hippocampus. 8C10 also protected against mCRP-induced inflammatory pathways in a microglial cell line, as shown by the prevention of increased generation of nitric oxide. Additional in vivo and in vitro neuroprotective testing with the anti-inflammatory agent TPPU, an inhibitor of the soluble epoxide hydrolase enzyme, confirmed the predominant involvement of neuroinflammatory processes in the dementia induced by mCRP. Therefore, locally deposited mCRP in the infarcted brain may be a novel biomarker for AD prognosis, and its antibody blockade opens up therapeutic opportunities for reducing post-stroke AD risk. ; This research was funded by the European Competitiveness Operational Programme 2014– 2020, C-Reactive protein therapy for stroke-associated dementia, ID P_37_674, MySMIS code: 103432, contract 51/05.09.2016; Spanish MINECO and European Regional Development Fund, grant number SAF2016-77703; Spanish MCINN, grant number PID2019-106285RB; Catalan Autonomous Government AGAUR, grant number 2017-SGR-106; the CERCA Programme/Generalitat de Catalunya. R.C was supported by a post-doctoral research contract of the Centro de Investigación Biomédica en Red de Epidemiología y Salud Pública (CIBERESP), Instituto de Salud Carlos III, Madrid, Spain.