BUSCADOR RECOLECTA

The Human Proteome Project (HPP) consortium aims to functionally characterize the dark proteome. On the basis of the relevance of olfaction in early neurodegeneration, we have analyzed the dark proteome using data mining in public resources and omics data sets derived from the human olfactory system. Multiple dark proteins localize at synaptic terminals and may be involved in amyloidopathies such as Alzheimer’s disease (AD). We have characterized the dark PITH domain-containing protein 1 (PITHD1) in olfactory metabolism using bioinformatics, proteomics, in vitro and in vivo studies, and neuropathology. PITHD1–/– mice exhibit olfactory bulb (OB) proteome changes related to synaptic transmission, cognition, and memory. OB PITHD1 expression increases with age in wild-type (WT) mice and decreases in Tg2576 AD mice at late stages. The analysis across 6 neurological disorders reveals that olfactory tract (OT) PITHD1 is specifically upregulated in human AD. Stimulation of olfactory neuroepithelial (ON) cells with PITHD1 alters the ON phosphoproteome, modifies the proliferation rate, and induces a pro-inflammatory phenotype. This workflow applied by the Spanish C-HPP and Human Brain Proteome Project (HBPP) teams across the ON-OB-OT axis can be adapted as a guidance to decipher functional features of dark proteins. Data are available via ProteomeXchange with identifiers PXD018784 and PXD021634.

A close epidemiological link has been reported between cannabis use and schizophrenia (SCZ). However, biochemical markers in living humans related to the impact of cannabis in this disease are still missing. Olfactory neuroepithelium (ON) cells express neural features and offer a unique advantage to study biomarkers of psychiatric diseases. The aim of our study was to find exclusively deregulated proteins in ON cells of SCZ patients with and without a history of cannabis use. Thus, we compared the proteomic profiles of SCZ non-cannabis users (SCZ/nc) and SCZ cannabis users (SCZ/c) with control subjects non-cannabis users (C/nc) and control cannabis users (C/c). The results revealed that the main cascades affected in SCZ/nc were cell cycle, DNA replication, signal transduction and protein localization. Conversely, cannabis use in SCZ patients induced specific alterations in metabolism of RNA and metabolism of proteins. The levels of targeted proteins in each population were then correlated with cognitive performance and clinical scores. In SCZ/c, the expression levels of 2 proteins involved in the metabolism of RNA (MTREX and ZNF326) correlated with several cognitive markers and clinical signs. Moreover, use duration of cannabis negatively correlated with ZNF326 expression. These findings indicate that RNA-related proteins might be relevant to understand the influence of cannabis use on SCZ.

Incluye material complementario, Amyotrophic lateral sclerosis (ALS) is a fatal disease characterized by progressive muscle paralysis due to the degeneration of upper and lower motor neurons. Recent studies point out an involvement of the non-motor axis during disease progression. Despite smell impairment being considered a potential non-motor finding in ALS, the pathobiochemistry at the olfactory level remains unknown. Here, we applied an olfactory quantitative proteotyping approach to analyze the magnitude of the olfactory bulb (OB) proteostatic imbalance in ALS subjects (n = 12) with respect to controls (n = 8). Around 3% of the quantified OB proteome was differentially expressed, pinpointing aberrant protein expression involved in vesicle-mediated transport, macroautophagy, axon development and gliogenesis in ALS subjects. The overproduction of olfactory marker protein (OMP) points out an imbalance in the olfactory signal transduction in ALS. Accompanying the specific overexpression of glial fibrillary acidic protein (GFAP) and Bcl-xL in the olfactory tract (OT), a tangled disruption of signaling routes was evidenced across the OB–OT axis in ALS. In particular, the OB survival signaling dynamics clearly differ between ALS and frontotemporal lobar degeneration (FTLD), two faces of TDP-43 proteinopathy. To the best of our knowledge, this is the first report on high-throughput molecular characterization of the olfactory proteostasis in ALS., This work was funded by grants from the Spanish Ministry of Science Innovation and Universities (Ref. PID2019-110356RB-I00 to JF-I and ES) and the Department of Economic and Business Development from Government of Navarra (Ref. 0011-1411-2020-000028 to ES). The study was also supported by the Ministry of Economy and Competiveness, Institute of Health Carlos III (ISCIII) (co-funded by European Regional Development Fund, ERDF, a way to build Europe): FISPI17/000809 to IF.

Despite the well-accepted role of the two main neuropathological markers (β-amyloid and tau) in the progression of Alzheimer’s disease, the interaction and specific contribution of each of them is not fully elucidated. To address this question, in the present study, an adeno-associated virus (AAV9) carrying the mutant P301L form of human tau, was injected into the dorsal hippocampi of APP/PS1 transgenic mice or wild type mice (WT). Three months after injections, memory tasks, biochemical and immunohistochemical analysis were performed. We found that the overexpression of hTauP301L accelerates memory deficits in APP/PS1 mice, but it did not affect memory function of WT mice. Likewise, biochemical assays showed that only in the case of APP/PS1-hTauP301L injected mice, an important accumulation of tau was observed in the insoluble urea fraction. Similarly, electron microscopy images revealed that numerous clusters of tau immunoparticles appear at the dendrites of APP/PS1 injected mice and not in WT animals, suggesting that the presence of amyloid is necessary to induce tau aggregation. Interestingly, these tau immunoparticles accumulate in dendritic mitochondria in the APP/PS1 mice, whereas most of mitochondria in WT injected mice remain free of tau immunoparticles. Taken together, it seems that amyloid induces tau aggregation and accumulation in the dendritic mitochondria and subsequently may alter synapse function, thus, contributing to accelerate cognitive decline in APP/PS1 mice., ) to J.F.-I. and E.S and from the Department of Economic and Business Development from Government of Navarra (INNOLFACT project; Ref. 0011-1411-2020-000028).We gratefully acknowledge grant funding support from Ministry of Science and Innovation (MINECO) with exp. PID2019-104921RB-I00/MCI/AEI/10.13039/501100011033as well as to the Foundation for Applied Medical Research, the University of Navarra (Pamplona, Spain) for financial support and the Asociación de Amigos of the University of Navarra for the grant to M.P.-G. and S.B. We also gratefully acknowledge grant funding support from Spanish Ministerio de Economía y Competitividad (RTI2018-095812-B-I00 MCIN/ AEI/10.13039/501100011033) y por FEDER una manera de hacer Europa and Junta de Comunidades de Castilla-La Mancha (SBPLY/17/180501/000229) to RL, from the Spanish Ministry of Science Innovation and Universities (Ref. PID2019-110356RB-I00/AEI/10.13039/501100011033

The most common form of mixed dementia (MixD) is constituted by abnormal protein deposits associated with Alzheimer's disease (AD) that coexist with vascular disease. Although olfactory dysfunction is considered a clinical sign of AD-related dementias, little is known about the impact of this sensorial impairment in MixD at the molecular level. To address this gap in knowledge, we assessed olfactory bulb (OB) proteome-wide expression in MixD subjects (n = 6) respect to neurologically intact controls (n = 7). Around 9% of the quantified proteins were differentially expressed, pinpointing aberrant proteostasis involved in synaptic transmission, nucleoside monophosphate and carbohydrate metabolism, and neuron projection regeneration. In addition, network-driven proteomics revealed a modulation in cell-survival related pathways such as ERK, AKT, and the PDK1-PKC axis. Part of the differential OB protein set was not specific of MixD, also being deregulated across different tauopathies, synucleinopathies, and tardopathies. However, the comparative functional analysis of OB proteome data between MixD and pure AD pathologies deciphered commonalities and differences between both related phenotypes. Finally, olfactory pro-teomics allowed to propose serum Prolow-density lipoprotein receptor-related protein 1 (LRP1) as a candidate marker to differentiate AD from MixD phenotypes., This work was funded by grants from the Spanish Ministry of Science, Innovation and Universities (Ref. PID2019-110356RB-I00/AEI/10.13039/501100011033) and the Department of Economic and Business Development from Government of Navarra (Ref. 0011-1411-2020-000028 to E.S.).

Next-generation proteomics has allowed the implementation of biomedical proteome research to uncover disease-affected protein expression profiles. It has also enabled the determination of protein localization, protein interactomes, posttranslational modifications and protein dysfunction in human diseases. Many pillars in personalized medicine, such as diagnostic improvements, drug screening, systems biology or bioinformatics, require the generation of quantitatively consistent proteomics data from translational animal models to human biospecimens to fill the information gap, making omics analysis actionable from a clinical perspective [1-3]. This Special Issue received multiple submissions, of which five original articles were accepted for publication. These contributions cover different phases of precision medicine in the context of proteomics: (i) discovery and quantitation of potential biomarker candidates (three articles), (ii) the proteostatic modulation and mechanisms of action of pharmacological compounds (one article) and (iii) the characterization of posttranslational modifications (one article)., This work was funded by grants from the Spanish Ministry of Science, Innovation and
Universities (Ref. PID2019-110356RB-I00/AEI/10.13039/501100011033) and the Department of
Economic and Business Development from Government of Navarra (Ref. 0011-1411-2020-000028).

Incluye material complementario, The Human Proteome Project (HPP) consortium aims to functionally characterize the dark proteome. On the basis of the relevance of olfaction in early neurodegeneration, we have analyzed the dark proteome using data mining in public resources and omics data sets derived from the human olfactory system. Multiple dark proteins localize at synaptic terminals and may be involved in amyloidopathies such as Alzheimer's disease (AD). We have characterized the dark PITH domain-containing protein 1 (PITHD1) in olfactory metabolism using bioinformatics, proteomics, in vitro and in vivo studies, and neuropathology. PITHD1-/- mice exhibit olfactory bulb (OB) proteome changes related to synaptic transmission, cognition, and memory. OB PITHD1 expression increases with age in wild-type (WT) mice and decreases in Tg2576 AD mice at late stages. The analysis across 6 neurological disorders reveals that olfactory tract (OT) PITHD1 is specifically upregulated in human AD. Stimulation of olfactory neuroepithelial (ON) cells with PITHD1 alters the ON phosphoproteome, modifies the proliferation rate, and induces a pro-inflammatory phenotype. This workflow applied by the Spanish C-HPP and Human Brain Proteome Project (HBPP) teams across the ON-OB-OT axis can be adapted as a guidance to decipher functional features of dark proteins. Data are available via ProteomeXchange with identifiers PXD018784 and PXD021634., This work was funded by grants from the Spanish Ministry of Science Innovation and Universities (ref. PID2019-110356RB-I00 to JFI and ES) and Department of Economic and Business Development from Government of Navarra (ref. 0011-1411-2020-000028) to ES and from MEXT-JSPS 17K08884 and Takeda Science Foundation to IO. The Proteomics Unit of Navarrabiomed is a member of Proteored (PRB3-ISCIII) and is supported by grant PT17/0019/009 to JFI, of the PE I+D+I 2013–2016 funded by ISCIII and FEDER. MLM was supported by a postdoctoral fellowship from the Public University of Navarra (UPNA).

Alzheimer’s disease (AD) is one of the most common neurodegenerative illnesses
displaying the highest death rate in the elderly. However, the existing AD
diagnostic system remains elusive due to lack of a technology that may ensure
enough sensitivity and reproducibility, detection accuracy, and specificity.
Herein, a straightforward approach is reported to realize lab-on-fiber (LoF)
technology for AD biomarker detection based on a D-shaped single-mode fiber
combined with nanometer-scale metal-oxide film. The proposed sensing system,
which permits the generation of lossy-mode resonance (LMR), remarkably
increases the evanescent field of light guided through the fiber, and hence the
fiber-surrounding medium interaction. Moreover, such optical sensors are highly
repeatable in results and can safely be embedded into a compact and stable
microfluidic system. Herein, the specific detection of Tau protein (as one of the
classical AD biomarkers that is highly correlated with AD progression) in a
complex biofluid with a detection limit of 10 12 M and over a wide concentration
range (10 3
–10 μg mL 1
) is successfully demonstrated. The proposed LoF
biosensor is an appealing solution for rapid, sub-microliter dose and highly
sensitive detection of analytes at low concentrations, hereby having the potential
toward early screening and personalized medicine in AD., F.C. gratefully acknowledges the support of the National Research Council of Italy (CNR) for the Short-Term Mobility programs 2017 and 2019. I.D.V. and I.R.M. acknowledge partial support of the Spanish Ministry of Economy and Competitiveness (Nos.TEC2016-79367-C2-2-R and PID2019-106231RB-I00), the predoctoral research grants of the Public University of Navarra and the Public University of Navarra grant PJUpna1936. E.S. and J.F-I. acknowledge partial support of the Spanish Ministry of Science, Innovation and Universities (PID2019-110356RB-I00/AEI/10.13039/501100011033). T.G.gratefully acknowledges the support of the National Natural Science Foundation of China (Nos. 62035006, 61975068, and 62011530459), the Guangdong Outstanding Scientific Innovation Foundation (No.2019TX05X383), and the Program of Marine Economy Development Special Fund (Six Marine Industries) under Department of Natural Resources of Guangdong Province (No. GDNRC [2021]33).

Extracellular vesicles (EVs) are key mediators of cell-to-cell communication. Their content reflects the state of diseased cells representing a window into disease progression. Collagen-VI Related Muscular Dystrophy (COL6-RD) is a multi-systemic disease involving different cell types. The role of EVs in this disease has not been explored. We compared by quantitative proteomics the protein cargo of EVs released from fibroblasts from patients with COL6-RD and controls. Isolated EVs contained a significant proportion of the most frequently reported proteins in EVs according to Exocarta and Vesiclepedia. We identified 67 differentially abundant proteins associated with vesicle transport and exocytosis, actin remodelling and the cytoskeleton, hemostasis and oxidative stress. Treatment of control fibroblasts with EVs from either patient or healthy fibroblasts altered significantly the motility of cells on a cell migration assay highlighting the functional relevance of EVs. In parallel, we analysed the secretome from the same cells and found a distinctly different set of 48 differentially abundant proteins related to extracellular matrix organisation and remodelling, growth factor response, RNA metabolism and the proteasome. The EVs and secretome sets of proteins only shared two identifiers indicating that the sorting of proteins towards EVs or the secretory pathway is tightly regulated for different functions. ., This work was funded by Plan Nacional de I + D + I and Instituto de Salud Carlos III (ISCIII), Subdirección General de Evaluación y Fomento de la Investigación Sanitaria (PI16/00579, PI19/00122) and Fundación Noelia. Spanish Ministry of Science, Innovation and Universities (PID2019-110356RB-I00/AEI/10.13039/501100011033).

The aim of this article is to present the research protocol for a prospective cohort study that will assess the olfactory function and the effect of an intervention based on olfactory training in healthy very old adults (≥75 years old). A convenience sample of 180 older people (50% female) will be recruited in three different environments: hospitalized control group (CH) with stable acute illness (n = 60); ambulatory control group (CA) of community-based living (n = 60); and an experimental odor training group (EOT) from nursing homes (n = 60). The odor training (OT) intervention will last 12 weeks. All the volunteers will be assessed at baseline; CA and EOT groups will also be assessed after 12 weeks. The primary end point will be change in olfactory capacity from baseline to 12 weeks period of intervention or control. The intervention effects will be assessed with the overall score achieved in Sniffin Sticks Test (SST) – Threshold, Discrimination, and Identification (TDI) extended version. Secondary end points will be changes in cognitive tasks, quality of life, mood, immune status, and functional capacity. All these measurements will be complemented with an immune fitness characterization and a deep proteome profiling of the olfactory epithelium (OE) cultured ex vivo. The current study will provide additional evidence to support the implementation of olfactory precision medicine and the development of immunomodulatory nasal therapies based on non-invasive procedures. The proposed intervention will also intend to increase the knowledge about the olfactory function in very elderly people, improve function and quality of life, and promote the recovery of the health., This work was funded by grants from the Spanish Ministry of Science Innovation and Universities (Ref. PID2019-110356RB-I00/AEI/10.13039/501100011033) to JF-I and ES, and Department of Economic and Business Development from Government of Navarra (INNOLFACT project; Ref. 0011-1411-2020-000028). NM-V received funding from 'la Caixa' Foundation (ID 100010434), under agreement LCF/PR/PR15/51100006.

Tau hyperphosphorylation is the first step of neurofibrillary tangle (NFT) formation. In the present study, samples of the entorhinal cortex (EC) and frontal cortex area 8 (FC) of cases with NFT pathology classified as stages I–II, III–IV, and V–VI without comorbidities, and of middle-aged (MA) individuals with no NFT pathology, were analyzed by conventional label-free and SWATH-MS (sequential window acquisition of all theoretical fragment ion spectra mass spectrometry) to assess the (phospho)proteomes. The total number of identified dysregulated phosphoproteins was 214 in the EC, 65 of which were dysregulated at the first stages (I–II) of NFT pathology; 167 phosphoproteins were dysregulated in the FC, 81 of them at stages I–II of NFT pathology. A large percentage of dysregulated phosphoproteins were identified in the two regions and at different stages of NFT progression. The main group of dysregulated phosphoproteins was made up of components of the membranes, cytoskeleton, synapses, proteins linked to membrane transport and ion channels, and kinases. The present results show abnormal phosphorylation of proteins at the first stages of NFT pathology in the elderly (in individuals clinically considered representative of normal aging) and sporadic Alzheimer's disease (sAD). Dysregulated protein phosphorylation in the FC precedes the formation of NFTs and SPs. The most active period of dysregulated phosphorylation is at stages III–IV when a subpopulation of individuals might be clinically categorized as suffering from mild cognitive impairment which is a preceding determinant stage in the progression to dementia. Altered phosphorylation of selected proteins, carried out by activation of several kinases, may alter membrane and cytoskeletal functions, among them synaptic transmission and membrane/cytoskeleton signaling. Besides their implications in sAD, the present observations suggest a molecular substrate for 'benign' cognitive deterioration in 'normal' brain aging., The Proteomics Platform of Navarrabiomed is a member of Proteored (PRB3‐ISCIII). The project leading to these results has received funding from 'La Caixa' Banking Foundation under the project HR18‐00452 to IF; it was also supported by the Ministry of Economy and Competitiveness, Institute of Health Carlos III (ISCIII) (co‐funded by European Regional Development Fund, ERDF, a way to build Europe): FISPI17/000809 to IF; co‐financed by ERDF under the program Interreg Poctefa: RedPrion 148/16 to IF; and the Intra‐CIBERNED 2019 collaborative project to IF and JADR. We thank CERCA Programme/Generalitat de Catalunya for institutional support. We also thank CIBERNED (Instituto de Salud Carlos III: ISCIII), Ministry of Economy and Competitiveness for institutional backing. The Proteomics Platform of Navarrabiomed is supported by grant PT17/0019/009 to JFI, of the PE I+D+I 2013‐2016 funded by ISCIII and FEDER. Part of this work was funded by a grant from the Spanish Ministry of Science Innovation and Universities (Ref. PID2019‐110356RB‐I00) to JFI and ES, and the Department of Economic and Business Development from the Government of Navarra (Ref. 0011‐1411‐2020‐000028) to ES

Sporadic amyotrophic lateral sclerosis (sALS) is a fatal progressive neurodegenerative disease affecting upper and lower motor neurons. Biomarkers are useful to facilitate the diagnosis and/or prognosis of patients and to reveal possible mechanistic clues about the disease. This study aimed to identify and validate selected putative biomarkers in the cerebrospinal fluid (CSF) of sALS patients at early disease stages compared with age-matched controls and with other neurodegenerative diseases including Alzheimer disease (AD), spinal muscular atrophy type III (SMA), frontotemporal dementia behavioral variant (FTD), and multiple sclerosis (MS). SWATH acquisition on liquid chromatography-tandem mass spectrometry (LC–MS/MS) for protein quantitation, and ELISA for validation, were used in CSF samples of sALS cases at early stages of the disease. Analysis of mRNA and protein expression was carried out in the anterior horn of the lumbar spinal cord in post-mortem tissue of sALS cases (terminal stage) and controls using RTq-PCR, and Western blotting, and immunohistochemistry, respectively. SWATH acquisition on liquid chromatography-tandem mass spectrometry (LC–MS/MS) revealed 51 differentially expressed proteins in the CSF in sALS. Receiver operating characteristic (ROC) curves showed CXCL12 to be the most valuable candidate biomarker. We validated the values of CXCL12 in CSF with ELISA in two different cohorts. Besides sALS, increased CXCL12 levels were found in MS but were not altered in AD, SMA, and FTD. Therefore, increased CXCL12 levels in the CSF can be useful in the diagnoses of MS and sALS in the context of the clinical settings. CXCL12 immunoreactivity was localized in motor neurons in control and sALS, and in a few glial cells in sALS at the terminal stage; CXCR4 was in a subset of oligodendroglial-like cells and axonal ballooning of motor neurons in sALS; and CXCR7 in motor neurons in control and sALS, and reactive astrocytes in the pyramidal tracts in terminal sALS. CXCL12/CXCR4/CXCR7 axis in the spinal cord probably plays a complex role in inflammation, oligodendroglial and astrocyte signaling, and neuronal and axonal preservation in sALS., The project leading to these results received funding from Fundació Miquel Valls, 'Retos todos unidos contra la ELA' and 'Proyecto DGeneracion conexiones con sentido' to MP. The study was also supported by the Ministry of Economy and Competitiveness, Institute of Health Carlos III (ISCIII) (co-funded by European RegiSonal Development Fund, ERDF, a way to build Europe): FISPI17/000809 to IF; and FIS (ISCIII) grant PI19/00144 to FLl. The Proteomics Unit of Navarrabiomed is supported by grant PT17/0019/009 to JFI, of the PE I+D+I 2013-2016 funded by ISCIII and FEDER. Part of this work was funded by a grant from the Spanish Ministry of Science Innovation and Universities (Ref. PID2019-110356RB-I00) to JFI and ES.

Aims: (Phospho)proteomics of old-aged subjects without cognitive or behavioral symptoms, and without ADneuropathological changes and lacking any other neurodegenerative alteration will increase understanding about
the physiological state of human brain aging without associate neurological deficits and neuropathological lesions.
Methods: (Phospho)proteomics using conventional label-free- and SWATH-MS (Sequential window acquisition of
all theoretical fragment ion spectra mass spectrometry) has been assessed in the frontal cortex (FC) of individuals
without NFTs, senile plaques (SPs) and age-related co-morbidities classified by age (years) in four groups; group 1
(young, 30–44); group 2 (middle-aged: MA, 45-52); group 3 (early-elderly, 64–70); and group 4 (late-elderly, 75–85).
Results: Protein levels and deregulated protein phosphorylation linked to similar biological terms/functions,
but involving different individual proteins, are found in FC with age. The modified expression occurs in
cytoskeleton proteins, membranes, synapses, vesicles, myelin, membrane transport and ion channels, DNA and
RNA metabolism, ubiquitin-proteasome-system (UPS), kinases and phosphatases, fatty acid metabolism, and
mitochondria. Dysregulated phosphoproteins are associated with the cytoskeleton, including microfilaments,
actin-binding proteins, intermediate filaments of neurons and glial cells, and microtubules; membrane proteins,
synapses, and dense core vesicles; kinases and phosphatases; proteins linked to DNA and RNA; members of the
UPS; GTPase regulation; inflammation; and lipid metabolism. Noteworthy, protein levels of large clusters of
hierarchically-related protein expression levels are stable until 70. However, protein levels of components of cell membranes, vesicles and synapses, RNA modulation, and cellular structures (including tau and tubulin
filaments) are markedly altered from the age of 75. Similarly, marked modifications occur in the larger
phosphoprotein clusters involving cytoskeleton and neuronal structures, membrane stabilization, and kinase
regulation in the late elderly.
Conclusions: Present findings may increase understanding of human brain proteostasis modifications in the
elderly in the subpopulation of individuals not having AD neuropathological change and any other
neurodegenerative change in any telencephalon region., The project leading to these results received funding from
the “la Caixa” Foundation (ID 100010434) under the
agreement LCF/PR/HR19/52160007, HR18-00452 to IF
and JAdR. We thank CERCA Programme/Generalitat de
Catalunya for institutional support. The Proteomics
Platform of Navarrabiomed is a member of Proteored
(PRB3-ISCIII) and is supported by grant PT17/0019/009
to JFI, of the PE I+D+I 2013–2016 funded by ISCIII and
FEDER. Parts of this work were funded by a grant from
the Spanish Ministry of Science Innovation and
Universities (Ref. PID2019-110356RB-I00) to JFI and
ES, and the Department of Economic and Business Development of the Government of Navarra (Ref. 0011-
1411-2020-000028) to ES.

One of the most common symptoms in COVID-19 is a sudden loss of smell. SARS-CoV-2 has been detected in the olfactory bulb (OB) from animal models and sporadically in COVID-19 patients. To decipher the specific role over the SARS-CoV-2 proteome at olfactory level, we characterized the in-depth molecular imbalance induced by the expression of GFP-tagged SARS-CoV-2 structural proteins (M, N, E, S) on mouse OB cells. Transcriptomic and proteomic trajectories uncovered a widespread metabolic remodeling commonly converging in extracellular matrix organization, lipid metabolism and signaling by receptor tyrosine kinases. The molecular singularities and specific interactome expression modules were also characterized for each viral structural factor. The intracellular molecular imbalance induced by each SARS-CoV-2 structural protein was accompanied by differential activation dynamics in survival and immunological routes in parallel with a differentiated secretion profile of chemokines in OB cells. Machine learning through a proteotranscriptomic data integration uncovered TGF-beta signaling as a confluent activation node by the SARS-CoV-2 structural proteome. Taken together, these data provide important avenues for understanding the multifunctional immunomodulatory properties of SARS-CoV-2 M, N, S and E proteins beyond their intrinsic role in virion formation, deciphering mechanistic clues to the olfactory inflammation observed in COVID-19 patients., This work was funded by grants from the Spanish Ministry of Science, Innovation and Universities (Ref. PID2019-110356RB-I00/AEI/10.13039/501100011033) to JF-I. and ES), the Department of Economic and Business Development from Government of Navarra (Ref. 0011-1411-2020-000028 to ES), the Instituto de Salud Carlos III (ISCIII)-FEDER project grants (Ref. FIS PI17/02119, FIS PI20/00010; COV20-00237 to DE), the Department of Health of the Government of Navarre (Ref: BMED 050-2019 to DE) and the European Project Horizon 2020 (ref: ID: 848166; Improved vaccination for older adults-ISOLDA to DE).

Olfactory dysfunction is considered an early prodromal marker of many neurodegenerative diseases. Neuropathological changes and aberrant protein aggregates occur in the olfactory bulb (OB), triggering a tangled cascade of molecular events that is not completely understood across neurological disorders. This study aims to analyze commonalities and differences in the olfactory protein homeostasis across neurological backgrounds with different spectrums of smell dysfunction. For that, an integrative analysis was performed using OB proteomics datasets derived from subjects with Alzheimer’s disease (AD), Parkinson´s disease (PD), mixed dementia (mixD), dementia with Lewy bodies (DLB), frontotemporal lobar degeneration (FTLD-TDP43), progressive supranuclear palsy (PSP) and amyotrophic lateral sclerosis (ALS) with respect to OB proteome data from neurologically intact controls. A total of 80% of the differential expressed protein products were potentially disease-specific whereas the remaining 20% were commonly altered across two, three or four neurological phenotypes. A multi-level bioinformatic characterization revealed a subset of potential disease-specific transcription factors responsible for the downstream effects detected at the proteome level as well as specific densely connected protein complexes targeted by several neurological phenotypes. Interestingly, common or unique pathways and biofunctions were also identified, providing novel mechanistic clues about each neurological disease at olfactory level. The analysis of olfactory epithelium, olfactory tract and primary olfactory cortical proteotypes in a multi-disease format will functionally complement the OB dyshomeostasis, increasing our knowledge about the neurodegenerative process across the olfactory axis., This work was funded by grants from the Spanish Ministry of Science, Innovation and Universities (Ref. PID2019-110356RB-I00/ AEI / 10.13039/501100011033 to JF-I and ES) and the Department of Economic and Business Development of the Government of Navarra (Ref. 0011-14112020-000028 to ES).The Proteomics Platform of Navarrabiomed, member of Proteored (PRB3ISCIII), was supported by grant PT17/0019/009, of the PE I+D+I 2013-2016 funded by ISCIII and FEDER to JF. The Clinical Neuroproteomics Unit of Navarrabiomed is member of the Spanish Olfactory Network (ROE) (supported by grant RED2018-102662-T funded by Spanish Ministry of Science and Innovation) and the Global Consortium for Chemosensory Research (GCCR).

Insulin-like growth factor-I (IGF-I) exerts multiple actions, yet the role of IGF-I from different sources is poorly understood. Here, we explored the functional and behavioral consequences of the conditional deletion of Igf-I in the nervous system (Igf-I¿/¿), and demonstrated that long-term potentiation was impaired in hippocampal slices. Moreover, Igf-I¿/¿ mice showed spatial memory deficits in the Morris water maze, and the significant sex-dependent differences displayed by Igf-ICtrl/Ctrl mice disappeared in Igf-I¿/¿ mice in the open field and rota-rod tests. Brain Igf-I deletion disorganized the granule cell layer of the dentate gyrus (DG), and it modified the relative expressions of GAD and VGLUT1, which are preferentially localized to inhibitory and excitatory presynaptic terminals. Furthermore, Igf-I deletion altered protein modules involved in receptor trafficking, synaptic proteins, and proteins that functionally interact with estrogen and androgen metabolism. Our findings indicate that brain IGF-I is crucial for long-term potentiation, and that it is involved in the regulation of spatial memory and sexual dimorphic behaviors, possibly by maintaining the granule cell layer structure and the stability of synaptic-related protein modules., This work was funded by grants from the Spanish “Ministerio Ciencia, Innovación y Universidades, and the Ministerio de Ciencia e Innovación/Agencia Estatal de Investigación” (MICIU and MICINN/AEI SAF2016-80419-R, PID2019-109059RB-100, and CIBERNED CB06/05/0065 to C Vicario; PID2019-110356RB-I00/AEI/10.13039/501100011033 to J Fernández-Irigoyen and E Santamaría; PID2019-104376RB-I00 to I Torres-Alemán; and PID2019-106579RB-I00 funded by MCIN/AEI/10.13039/501100011033 and by “ERDF A way of making Europe to G Perea, and BES-2017-080303 to C González-Arias.

Background Smell impairment is one of the earliest features in Alzheimer’s (AD) and Parkinson’s diseases (PD).
Due to sex diferences exist in terms of smell and olfactory structures as well as in the prevalence and manifestation
of both neurological syndromes, we have applied olfactory proteomics to favor the discovery of novel sex-biased
physio-pathological mechanisms and potential therapeutic targets associated with olfactory dysfunction.
Methods SWATH-MS (sequential window acquisition of all theoretical fragment ion spectra mass spectrometry) and
bioinformatic workfows were applied in 57 post-mortem olfactory tracts (OT) derived from controls with no known
neurological history (n=6F/11M), AD (n=4F/13M) and PD (n=7F/16M) subjects. Complementary molecular analyses
by Western-blotting were performed in the olfactory bulb (OB), entorhinal cortex (EC) and amygdala areas.
Results 327 and 151 OT diferentially expressed proteins (DEPs) were observed in AD women and AD men, respec‑
tively (35 DEPs in common). With respect to PD, 198 DEPs were identifed in PD women, whereas 95 DEPs were
detected in PD men (20 DEPs in common). This proteome dyshomeostasis induced a disruption in OT protein interac‑
tion networks and widespread sex-dependent pathway perturbations in a disease-specifc manner, among them
Sirtuin (SIRT) signaling. SIRT1, SIRT2, SIRT3 and SIRT5 protein levels unveiled a tangled expression profle across the
olfactory–entorhinal–amygdaloid axis, evidencing disease-, sex- and brain structure-dependent changes in olfactory
protein acetylation.
Conclusions Alteration in the OT proteostasis was more severe in AD than in PD. Moreover, protein expression
changes were more abundant in women than men independent of the neurological syndrome. Mechanistically, the
tangled SIRT profle observed across the olfactory pathway-associated brain regions in AD and PD indicates difer‑
ential NAD (+)-dependent deacetylase mechanisms between women and men. All these data shed new light on
diferential olfactory mechanisms across AD and PD, pointing out that the evaluation of the feasibility of emerging
sirtuin-based therapies against neurodegenerative diseases should be considered with caution, including further sex
dimension analyses in vivo and in clinical studies., The Proteomics Platform of Navarrabiomed was member of Proteored (PRB3-ISCIII) supported by grant PT17/0019/009, of the PE I+D+I 2013–2016 funded by ISCIII and FEDER. The Clinical Neuroproteomics Unit of Navarrabiomed is member of the Global Consortium for Chemosensory Research (GCCR) and the Spanish Olfactory Network (ROE) (supported by grant RED2018-102662-T funded by Spanish Ministry of Science and Innovation). This work was funded by grants from the Spanish Ministry of Science, Innovation and Universities (Ref. PID2019-110356RB-I00/AEI/10.13039/501100011033). to J.F.-I. and E.S.) and the Department of Economic and Business Development from Government of Navarra (Ref. 0011-1411-2020-000028 to E.S.). PC-C was supported by a predoctoral fellowship from the Public University of Navarra (UPNA).

Transcriptomics and phosphoproteomics were carried out in the cerebral cortex of B6.Cg-Mapttm1(EGFP)Klt (tau knockout: tau-KO) and wild-type (WT) 12 month-old mice to learn about the effects of tau ablation. Compared with WT mice, tau-KO mice displayed reduced anxiety-like behavior and lower fear expression induced by aversive conditioning, whereas recognition memory remained unaltered. Cortical transcriptomic analysis revealed 69 downregulated and 105 upregulated genes in tau-KO mice, corresponding to synaptic structures, neuron cytoskeleton and transport, and extracellular matrix components. RT-qPCR validated increased mRNA levels of col6a4, gabrq, gad1, grm5, grip2, map2, rab8a, tubb3, wnt16, and an absence of map1a in tau-KO mice compared with WT mice. A few proteins were assessed with Western blotting to compare mRNA expression with corresponding protein levels. Map1a mRNA and protein levels decreased. However, ¿-tubulin III and GAD1 protein levels were reduced in tau-KO mice. Cortical phosphoproteomics revealed 121 hypophosphorylated and 98 hyperphosphorylated proteins in tau-KO mice. Deregulated phosphoproteins were categorized into cytoskeletal (n = 45) and membrane proteins, including proteins of the synapses and vesicles, myelin proteins, and proteins linked to membrane transport and ion channels (n = 84), proteins related to DNA and RNA metabolism (n = 36), proteins connected to the ubiquitin-proteasome system (UPS) (n = 7), proteins with kinase or phosphatase activity (n = 21), and 22 other proteins related to variegated pathways such as metabolic pathways, growth factors, or mitochondrial function or structure. The present observations reveal a complex altered brain transcriptome and phosphoproteome in tau-KO mice with only mild behavioral alterations., The project leading to these results received funding from the “la Caixa” Foundation (ID 100010434) under the agreements LCF/PR/HR19/52160007, HR18-00452 to IF. We thank the CERCA Programme/Generalitat de Catalunya for institutional support. The Proteomics Platform of Navarrabiomed is a member of Proteored (PRB3-ISCIII), supported by grant PT17/0019/009 to J.F.-I. of the PE I + D + I 2013-2016 funded by ISCIII and FEDER. This work was funded by a grant from the Spanish Ministry of Science, Innovation, and Universities (Ref. PID2019-110356RB-I00) to J.F.-I. and E.S. and the Department of Economic and Business Development from the Government of Navarra (Ref. 0011-1411-2020-000028) to E.S.

Insulin-like growth factor-I (IGF-I) exerts multiple actions, yet the role of IGF-I from different sources is poorly understood. Here, we explored the functional and behavioral consequences of the conditional deletion of Igf-I in the nervous system (Igf-I Δ/Δ), and demonstrated that long-term potentiation was impaired in hippocampal slices. Moreover, Igf-I Δ/Δ mice showed spatial memory deficits in the Morris water maze, and the significant sex-dependent differences displayed by Igf-I Ctrl/Ctrl mice disappeared in Igf-I Δ/Δ mice in the open field and rota-rod tests. Brain Igf-I deletion disorganized the granule cell layer of the dentate gyrus (DG), and it modified the relative expressions of GAD and VGLUT1, which are preferentially localized to inhibitory and excitatory presynaptic terminals. Furthermore, Igf-I deletion altered protein modules involved in receptor trafficking, synaptic proteins, and proteins that functionally interact with estrogen and androgen metabolism. Our findings indicate that brain IGF-I is crucial for long-term potentiation, and that it is involved in the regulation of spatial memory and sexual dimorphic behaviors, possibly by maintaining the granule cell layer structure and the stability of synaptic-related protein modules., We thank Lucía Vicario (Instituto Cajal-CSIC, Madrid, Spain) for helping with the composition of the figures, and Dr. M Sefton (BiomedRed SL, Madrid, Spain) for English editing. This work was funded by grants from the Spanish “Ministerio Ciencia, Innovación y Universidades, and the Ministerio de Ciencia e Innovación/Agencia Estatal de Investigación” (MICIU and MICINN/AEI SAF2016-80419-R, PID2019-109059RB-100, and CIBERNED CB06/05/0065 to C Vicario; PID2019-110356RB-I00/AEI/10.13039/501100011033 to J Fernández-Irigoyen and E Santamaría; PID2019-104376RB-I00 to I Torres-Alemán; and PID2019-106579RB-I00 funded by MCIN/AEI/10.13039/501100011033 and by “ERDF A way of making Europe to G Perea, and BES-2017-080303 to C González-Arias).

Insulin-like growth factor-I (IGF-I) exerts multiple actions, yet the role of IGF-I from different sources is poorly understood. Here, we explored the functional and behavioral consequences of the conditional deletion of Igf-I in the nervous system (Igf-IΔ/Δ), and demonstrated that long-term potentiation was impaired in hippocampal slices. Moreover, Igf-IΔ/Δ mice showed spatial memory deficits in the Morris water maze, and the significant sex-dependent differences displayed by Igf-ICtrl/Ctrl mice disappeared in Igf-IΔ/Δ mice in the open field and rota-rod tests. Brain Igf-I deletion disorganized the granule cell layer of the dentate gyrus (DG), and it modified the relative expressions of GAD and VGLUT1, which are preferentially localized to inhibitory and excitatory presynaptic terminals. Furthermore, Igf-I deletion altered protein modules involved in receptor trafficking, synaptic proteins, and proteins that functionally interact with estrogen and androgen metabolism. Our findings indicate that brain IGF-I is crucial for long-term potentiation, and that it is involved in the regulation of spatial memory and sexual dimorphic behaviors, possibly by maintaining the granule cell layer structure and the stability of synaptic-related protein modules., We thank Lucía Vicario (Instituto Cajal-CSIC, Madrid, Spain) for helping with the composition of the figures, and Dr. M Sefton (BiomedRed SL, Madrid, Spain) for English editing. This work was funded by grants from the Spanish “Ministerio Ciencia, Innovación y Universidades, and the Ministerio de Ciencia e Innovación/Agencia Estatal de Investigación” (MICIU and MICINN/AEI SAF2016-80419-R, PID2019-109059RB-100, and CIBERNED CB06/05/0065 to C Vicario; PID2019-110356RB-I00/AEI/10.13039/501100011033 to J Fernández-Irigoyen and E Santamaría; PID2019-104376RB-I00 to I Torres-Alemán; and PID2019-106579RB-I00 funded by MCIN/AEI/10.13039/501100011033 and by “ERDF A way of making Europe to G Perea, and BES-2017-080303 to C González-Arias).