INTRODUCTION: Chitinase-3-like protein 1 (CHI3L1) is a glycoprotein implicated in various neurological conditions. It is associated with neuroinflammation and tissue remodeling. The study aimed to validate the reference interval (RI) of serum (S) CHI3L1 in a control group, to correlate S CHI3L1 values with other biomarkers of neurodegenerative damage, and to estimate the diagnostic accuracy of S CHI3L1. METHODS: Samples from 108 healthy volunteers were used to estimate the S CHI3L1 RI. For the comparison, we used cerebrospinal fluid (CSF) and serum (S) samples from 121 patients with cognitive disorders, and cognitive deterioration was assessed using the Mini-Mental State Examination (MMSE). ELISA assays were used to determine the S CHI3L1, CSF, and S neurofilament light chain (NfL) levels; CSF and plasma β-amyloid peptide42; CSF and plasma β-amyloid peptide40; CSF total tau protein; CSF phosphorylated tau protein; and CSF alpha-synuclein. RESULTS: The estimated RI of S CHI3L1 was 14.44 to 63.11 μg/L. The cut-off value of S CHI3L1 was 34.37 μg/L. ROC analysis showed that S CHI3L1 has 81.4% sensitivity and 76.9% specificity. We found a moderate Spearman's rank correlation coefficient between the S CHI3L1 and age (rS = 0.486; p < 0.001) and between S CHI3L1 and S NfL (rS = 0.489; p < 0.001) in all groups. The Kruskal-Wallis test showed a significant overall difference in S CHI3L1 among diagnostic groups (p = 0.013). S CHI3L1 and CSF NfL had statistically significant effects on MMSE values (multiple R2 was 0.431). CONCLUSIONS: Our results suggest that S CHI3L1 reflects the severity of cognitive deficits assessed by MMSE. It can be used as a supportive biomarker in neurodegenerative diseases.

• MeSH
• alpha-Synuclein cerebrospinal fluid   blood   MeSH
• Amyloid beta-Peptides blood   cerebrospinal fluid   MeSH
• Biomarkers blood   cerebrospinal fluid   MeSH
• Adult MeSH
• Cognitive Dysfunction * blood   cerebrospinal fluid   diagnosis   MeSH
• Middle Aged MeSH
• Humans MeSH
• Neurofilament Proteins cerebrospinal fluid   blood   MeSH
• Movement Disorders * blood   cerebrospinal fluid   diagnosis   MeSH
• Chitinase-3-Like Protein 1 * blood   cerebrospinal fluid   MeSH
• tau Proteins cerebrospinal fluid   blood   MeSH
• Aged, 80 and over MeSH
• Aged MeSH
• Check Tag
• Adult MeSH
• Middle Aged MeSH
• Humans MeSH
• Male MeSH
• Aged, 80 and over MeSH
• Aged MeSH
• Female MeSH
• Publication type
• Journal Article MeSH
• Comparative Study MeSH

BACKGROUND: Spatial navigation deficits are early symptoms of Alzheimer's disease (AD). The apolipoprotein E (APOE) ε4 allele is the most important genetic risk factor for AD. This study investigated effects of APOE genotype on spatial navigation in biomarker-defined individuals with amnestic mild cognitive impairment (aMCI) and associations of AD biomarkers and atrophy of AD-related brain regions with spatial navigation. METHODS: 107 participants, cognitively normal older adults (CN, n = 48) and aMCI individuals stratified into AD aMCI (n = 28) and non-AD aMCI (n = 31) groups, underwent cognitive assessment, brain MRI, and spatial navigation assessment using the Virtual Supermarket Test with egocentric and allocentric tasks and a self-report questionnaire. Cerebrospinal fluid (CSF) biomarkers (amyloid-β1-42, phosphorylated tau181 and total tau) and amyloid PET imaging were assessed in aMCI participants. RESULTS: AD aMCI participants had the highest prevalence of APOE ε4 carriers and worst allocentric navigation. CSF levels of AD biomarkers and atrophy in AD-related brain regions were associated with worse allocentric navigation. Between-group differences in spatial navigation and associations with AD biomarkers and regional brain atrophy were not influenced by APOE genotype. Self-reported navigation ability was similar across groups and unrelated to spatial navigation performance. CONCLUSIONS: These findings suggest that allocentric navigation deficits in aMCI individuals are predominantly driven by AD pathology, independent of APOE genotype. This highlights the role of AD pathology as measured by biomarkers, rather than genetic status, as a major factor in navigational impairment in aMCI, and emphasizes the assessment of spatial navigation as a valuable tool for early detection of AD.

• MeSH
• Alzheimer Disease * genetics   cerebrospinal fluid   diagnostic imaging   complications   physiopathology   pathology   MeSH
• Amyloid beta-Peptides cerebrospinal fluid   MeSH
• Apolipoprotein E4 * genetics   MeSH
• Apolipoproteins E * genetics   MeSH
• Atrophy MeSH
• Biomarkers cerebrospinal fluid   MeSH
• Genotype MeSH
• Cognitive Dysfunction * genetics   cerebrospinal fluid   diagnostic imaging   physiopathology   MeSH
• Middle Aged MeSH
• Humans MeSH
• Magnetic Resonance Imaging MeSH
• Brain pathology   diagnostic imaging   MeSH
• Neuropsychological Tests MeSH
• Peptide Fragments cerebrospinal fluid   MeSH
• Positron-Emission Tomography MeSH
• Spatial Navigation * physiology   MeSH
• tau Proteins cerebrospinal fluid   MeSH
• Aged, 80 and over MeSH
• Aged MeSH
• Check Tag
• Middle Aged MeSH
• Humans MeSH
• Male MeSH
• Aged, 80 and over MeSH
• Aged MeSH
• Female MeSH
• Publication type
• Journal Article MeSH

Pulmonary alveolar proteinosis (PAP) is a rare disease characterised by excessive accumulation of surfactant components in alveolar macrophages, alveoli, and peripheral airways. The accumulation of surfactant is associated with only a minimal inflammatory response but can lead to the development of pulmonary fibrosis. Three clinical forms of PAP are distinguished - primary, secondary and congenital. In recent years, significant findings have helped to clarify the ethiology and pathogenesis of the disease. Apart from impaired surfactant protein function, a key role in the development of PAP is played by signal pathway of granulocyte and macrophage colonies stimulating growth factor (GM-CSF) which is necessary for the functioning of alveolar macrophages and for surfactant homeostasis. Surfactant is partially degraded by alveolar macrophages that are stimulated by GM-CSF. The role of GM-CSF has been shown especially in primary PAP, which is currently considered an autoimmune disease involving the development of GM-CSF neutralising autoantibodies. Clinically, the disease may be silent or manifest with dyspnoeic symptoms triggered by exertion and cough. However, there is a 10 to 15% rate of patients who develop respiratory failure. Total pulmonary lavage is regarded as the standard method of treatment. In addition, recombinant human GM-CSF has been studied as a prospective therapy for the treatment of PAP.

• MeSH
• Macrophages, Alveolar * immunology   pathology   MeSH
• Granulocyte-Macrophage Colony-Stimulating Factor * metabolism   MeSH
• Humans MeSH
• Pulmonary Alveolar Proteinosis * pathology   MeSH
• Rare Diseases * pathology   MeSH
• Animals MeSH
• Check Tag
• Humans MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Review MeSH

OBJECTIVE: Dementia with Lewy bodies (DLB) and Parkinson's disease (PD) share clinical, pathological, and genetic risk factors, including GBA1 and APOEε4 mutations. Biomarkers associated with the pathways of these mutations, such as glucocerebrosidase enzyme (GCase) activity and amyloid-beta 42 (Aβ42) levels, may hold potential as predictive indicators, providing valuable insights into the likelihood of cognitive decline within these diagnoses. Our objective was to determine their association with cognitive decline in DLB and PD. METHODS: A total of 121 DLB patients from the European-DLB Consortium and 117 PD patients from the Norwegian ParkWest Study were included in this study. The four most commonly associated variants of GBA1 mutations (E326K, T369M, N370S, L444P), APOEε4 status, and cerebrospinal fluid (CSF) Aβ42 levels and GCase activity were assessed, as well as global cognition using the Mini-Mental State Examination. Linear mixed-effects regression models were used to evaluate the association of CSF biomarkers with cognitive decline in each diagnostic group, adjusted for age, sex, education, and genetic mutation profile. RESULTS: Low CSF Aβ42 levels were associated with accelerated cognitive decline in DLB, whereas reduced CSF GCase activity predicted faster cognitive decline in PD. These associations were independent of GBA1 gene mutations or APOEε4 status. INTERPRETATION: Our study provides important evidence on the relationship between brain Aβ deposition and GCase activity in the Lewy body disease spectrum independent of their genetic mutation profile. This information could be relevant for designing future clinical trials targeting these pathways.

• MeSH
• Amyloid beta-Peptides * cerebrospinal fluid   MeSH
• Biomarkers cerebrospinal fluid   MeSH
• Lewy Body Disease * cerebrospinal fluid   genetics   complications   MeSH
• Glucosylceramidase * genetics   metabolism   cerebrospinal fluid   MeSH
• Cognitive Dysfunction * cerebrospinal fluid   genetics   etiology   MeSH
• Middle Aged MeSH
• Humans MeSH
• Parkinson Disease * cerebrospinal fluid   genetics   complications   MeSH
• Peptide Fragments * cerebrospinal fluid   MeSH
• Aged, 80 and over MeSH
• Aged MeSH
• Check Tag
• Middle Aged MeSH
• Humans MeSH
• Male MeSH
• Aged, 80 and over MeSH
• Aged MeSH
• Female MeSH
• Publication type
• Journal Article MeSH

While diagnostic criteria have been established and validated for most neurodegenerative diseases, the considerable overlap between individual nosological entities remains a significant diagnostic challenge. Increasing evidence suggests that neurodegeneration is often initiated by inflammation within the central nervous system. The identification of inflammation could serve as a first signal of the pathophysiological process. As such, validated biological markers ("biomarkers") of neuroinflammation are critically important. This study aimed to assess the presence and levels of inflammatory biomarkers in three neurodegenerative diseases: Lewy body diseases (LBD), multiple system atrophy (MSA), and 4-repeat tauopathies (4RT). A total of 83 LBD, 24 MSA, and 31 4RT patients were included, with 83 control subjects for comparison. Six immune-related proteins were analysed in cerebrospinal fluid (CSF) and blood serum (serum): C3 complement, C4 complement, haptoglobin, transferrin, orosomucoid, and β2 microglobulin (β2M). ANCOVA statistical analysis revealed significantly lower levels of several inflammatory biomarkers in LBD (CSF: transferrin, C3 complement, orosomucoid; Serum: orosomucoid, β2M) and MSA (CSF: transferrin, C3 complement, C4 complement, orosomucoid) compared to controls. Significant differences were also observed between the synucleinopathy patient groups (LBD and MSA) and 4RT in serum levels of C3 complement. Additionally, the CSF/serum quotients for transferrin (LBD and MSA) and C3 complement (LBD) were significantly lower in disease relative to controls. These findings suggest that inflammatory processes may play a role in the pathophysiology of neurodegenerative proteinopathies, warranting further research to confirm these associations. The identification of potential fluid biomarkers would then represent a promising step forward in the field.

• MeSH
• Biomarkers blood   cerebrospinal fluid   MeSH
• Lewy Body Disease * blood   cerebrospinal fluid   MeSH
• Middle Aged MeSH
• Humans MeSH
• Multiple System Atrophy * blood   cerebrospinal fluid   MeSH
• Neuroinflammatory Diseases * blood   cerebrospinal fluid   MeSH
• Aged MeSH
• Case-Control Studies MeSH
• Tauopathies * blood   cerebrospinal fluid   MeSH
• Check Tag
• Middle Aged MeSH
• Humans MeSH
• Male MeSH
• Aged MeSH
• Female MeSH
• Publication type
• Journal Article MeSH
• Comparative Study MeSH

Regulation of neuroimmune interactions varies across avian species. Little is presently known about the interplay between periphery and central nervous system (CNS) in parrots, birds sensitive to neuroinflammation. Here we investigated the systemic and CNS responses to dextran sulphate sodium (DSS)- and lipopolysaccharide (LPS)-induced subclinical acute peripheral inflammation in budgerigar (Melopsittacus undulatus). Three experimental treatment groups differing in DSS and LPS stimulation were compared to controls. Individuals treated with DSS showed significant histological intestinal damage. Through quantitative proteomics we described changes in plasma (PL) and cerebrospinal fluid (CSF) composition. In total, we identified 180 proteins in PL and 978 proteins in CSF, with moderate co-structure between the proteomes. Between treatments we detected differences in immune, coagulation and metabolic pathways. Proteomic variation was associated with the levels of pro-inflammatory cytokine mRNA expression in intestine and brain. Our findings shed light on systemic impacts of peripheral low-grade inflammation in birds.

• MeSH
• Central Nervous System * metabolism   immunology   MeSH
• Cytokines metabolism   MeSH
• Lipopolysaccharides * immunology   MeSH
• Melopsittacus * immunology   MeSH
• Brain metabolism   immunology   MeSH
• Bird Diseases immunology   metabolism   MeSH
• Neuroimmunomodulation MeSH
• Neuroinflammatory Diseases immunology   MeSH
• Proteome * metabolism   MeSH
• Proteomics methods   MeSH
• Avian Proteins metabolism   genetics   MeSH
• Dextran Sulfate * MeSH
• Intestines immunology   MeSH
• Inflammation * immunology   metabolism   MeSH
• Animals MeSH
• Check Tag
• Animals MeSH
• Publication type
• Journal Article MeSH

Defective mitophagy is consistently found in postmortem brain and iPSC-derived neurons from Alzheimer disease (AD) patients. However, there is a lack of extensive examination of mitophagy status in serum or cerebrospinal fluid (CSF), and the clinical potential of mitophagy biomarkers has not been tested. We quantified biomarkers of mitophagy/autophagy and lysosomal degradation (PINK1, BNIP3L and TFEB) in CSF and serum from 246 individuals, covering mild cognitive impairment due to AD (MCI-AD, n = 100), dementia due to AD (AD-dementia, n = 100), and cognitively unimpaired individuals (CU, n = 46), recruited from the Czech Brain Aging Study. Cognitive function and brain atrophy were also assessed. Our data show that serum and CSF PINK1 and serum BNIP3L were higher, and serum TFEB was lower in individuals with AD than in corresponding CU individuals. Additionally, the magnitude of mitophagy impairment correlated with the severity of clinical indicators in AD patients. Specifically, levels of PINK1 positively correlated with phosphorylated (p)-MAPT/tau (181), total (t)-MAPT/tau, NEFL (neurofilament light chain), and NRGN (neurogranin) levels in CSF and negatively with memory, executive function, and language domain. Serum TFEB levels negatively correlated with NEFL and positively with executive function and language. This study reveals mitophagy impairment reflected in biofluid biomarkers of individuals with AD and associated with more advanced AD pathology.Abbreviation: Aβ: amyloid beta; AD: Alzheimer disease; AVs: autophagic vacuoles; BNIP3L: BCL2 interacting protein 3 like; CU: cognitively unimpaired; CSF: cerebrospinal fluid; LAMP1: lysosomal-associated membrane protein 1; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; MCI: mild cognitive impairment; NRGN: neurogranin; NEFL: neurofilament light chain; p-MAPT/tau: phosphorylated microtubule associated protein tau; PINK1: PTEN induced kinase 1; t-MAPT/tau: total microtubule associated protein tau; TFEB: transcription factor EB; TMT: Trail Making Test.

• MeSH
• Alzheimer Disease * cerebrospinal fluid   blood   diagnosis   MeSH
• Biomarkers * cerebrospinal fluid   blood   metabolism   MeSH
• Cognitive Dysfunction cerebrospinal fluid   blood   diagnosis   MeSH
• Middle Aged MeSH
• Humans MeSH
• Membrane Proteins cerebrospinal fluid   metabolism   blood   MeSH
• Mitophagy * MeSH
• Brain metabolism   pathology   MeSH
• Tumor Suppressor Proteins MeSH
• Protein Kinases metabolism   MeSH
• tau Proteins cerebrospinal fluid   metabolism   MeSH
• Proto-Oncogene Proteins cerebrospinal fluid   blood   metabolism   MeSH
• Aged, 80 and over MeSH
• Aged MeSH
• Basic Helix-Loop-Helix Leucine Zipper Transcription Factors metabolism   MeSH
• Check Tag
• Middle Aged MeSH
• Humans MeSH
• Male MeSH
• Aged, 80 and over MeSH
• Aged MeSH
• Female MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH

BACKGROUND: Serum neurofilament light chain (S NfL) is a non-specific marker of neuronal damage, including Alzheimer's disease (AD). We aimed to verify the reference interval (RI) of serum NfL using a highly sensitive ELISA, and to estimate the optimal cut-off value for neuronal damage. Our second objective was to compare NfL in cerebrospinal fluid (CSF) and serum (S) with the routine neurodegeneration biomarkers used in AD, and to assess their concentrations relative to the degree of cognitive deficit. METHODS: Samples from 124 healthy volunteers were used to estimate the S NfL RI. For the comparison study, we used CSF and S samples from 112 patients with cognitive disorders. Cognitive functions were assessed using the mini-mental state examination. ELISA assays were used to determine the CSF and S NfL levels, CSF β-amyloid peptide42 (Aβ42), CSF β-amyloid peptide40 (Aβ40), CSF total tau protein (tTau), CSF phosphorylated tau protein (pTau), and CSF alpha-synuclein (αS). RESULTS: The estimated RI of S NfL were 2.25-9.19 ng.L-1. The cut-off value of S NfL for assessing the degree of neuronal impairment was 10.5 ng.L-1. We found a moderate statistically significant correlation between S NfL and CSF Aβ42 in the group with movement disorders, without dementia (rs = 0.631; p = 0.016); between S NfL and CSF Aβ40 in the group with movement disorder plus dementia (rs = -0.750; p = 0.052); between S NfL and CSF tTau in the control group (rs = 0.689; p = 0.009); and between S NfL and CSF pTau in the control group (rs = 0.749; p = 0.003). The non-parametric Kruskal-Wallis test revealed statistically significant differences between S NfL, CSF NfL, CSF Aβ42, CSF tTau, and CSF pTau and diagnosis within groups. The highest kappa coefficients were found between the concentrations of S NfL and CSF NfL (κ = 0.480) and between CSF NfL and CSF tTau (κ = 0.351). CONCLUSION: Our results suggested that NfL and tTau in CSF of patients with cognitive decline could be replaced by the less-invasive determination of S NfL using a highly sensitive ELISA method. S NfL reflected the severity of cognitive deficits assessed by mini-mental state examination (MMSE). However, S NfL is not specific to AD and does not appear to be a suitable biomarker for early diagnosis of AD.

• Publication type
• Journal Article MeSH

OBJECTIVE: Amyotrophic lateral sclerosis (ALS) is a heterogeneous disease with a complex etiology that lacks biomarkers predicting disease progression. The objective of this study was to use longitudinal cerebrospinal fluid (CSF) samples to identify biomarkers that distinguish fast progression (FP) from slow progression (SP) and assess their temporal response. METHODS: We utilized mass spectrometry (MS)-based proteomics to identify candidate biomarkers using longitudinal CSF from a discovery cohort of SP and FP ALS patients. Immunoassays were used to quantify and validate levels of the top biomarkers. A state-transition mathematical model was created using the longitudinal MS data that also predicted FP versus SP. RESULTS: We identified a total of 1148 proteins in the CSF of all ALS patients. Pathway analysis determined enrichment of pathways related to complement and coagulation cascades in FPs and synaptogenesis and glucose metabolism in SPs. Longitudinal analysis revealed a panel of 59 candidate markers that could segregate FP and SP ALS. Based on multivariate analysis, we identified three biomarkers (F12, RBP4, and SERPINA4) as top candidates that segregate ALS based on rate of disease progression. These proteins were validated in the discovery and a separate validation cohort. Our state-transition model determined that the overall variance of the proteome over time was predictive of the disease progression rate. INTERPRETATION: We identified pathways and protein biomarkers that distinguish rate of ALS disease progression. A mathematical model of the CSF proteome determined that the change in entropy of the proteome over time was predictive of FP versus SP.

• MeSH
• Amyotrophic Lateral Sclerosis * MeSH
• Biomarkers cerebrospinal fluid   MeSH
• Humans MeSH
• Retinol-Binding Proteins, Plasma MeSH
• Disease Progression MeSH
• Proteome metabolism   MeSH
• Proteomics methods   MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Research Support, N.I.H., Extramural MeSH

BACKGROUND AND PURPOSE: N-methyl-d-aspartate receptor (NMDAR) and leucine-rich glioma-inactivated protein 1 (LGI1) encephalitis are important types of autoimmune encephalitis (AE) with significant morbidity. In this study, we used a proteomic approach in search of novel clinically relevant biomarkers in these types of encephalitides. METHODS: Swedish and Czech tertiary neuroimmunology centers collaborated in this retrospective exploratory study. Fifty-eight cerebrospinal fluid (CSF) samples of 28 patients with AE (14 definite NMDAR, 14 with definite LGI1 encephalitis) and 30 controls were included. CSF samples were analyzed using proximity extension assay technology (Olink Target 96 Inflammation panel). For each CSF sample, 92 proteins were measured. Clinical variables were retrospectively collected, and correlations with protein levels were statistically analyzed. RESULTS: Patients and controls differed significantly in the following 18 biomarkers: TNFRSF9, TNFRSF12, TNFRSF14, TNFβ, TNFα, IL7, IL10, IL12B, IFNγ, CD5, CD6, CASP8, MMP1, CXCL8, CXCL10, CXCL11, IL20RA, and sirtuin 2 (SIRT2). In LGI1 encephalitis, no clinically useful association was found between biomarkers and clinical variables. In the NMDAR encephalitis group, SIRT2, TNFβ, and CD5 were significantly associated with ovarian teratoma. For SIRT2, this was true even for the first patients' CSF sample (SIRT2 without vs. with tumor, mean ± SD = 2.2 ± 0.29 vs. 2.88 ± 0.48; p = 0.007, 95% confidence interval = -1.15 to -0.22; r statistic in point-biserial correlation (rpb) = 0.66, p = 0.011). SIRT2 was positively correlated with age (rpb = 0.39, p = 0.018) and total hospital days (r = 0.55, p = <0.001). CONCLUSIONS: SIRT2 should be investigated as a biomarker of paraneoplastic etiology in NMDAR encephalitis.

• MeSH
• Autoantibodies MeSH
• Biomarkers cerebrospinal fluid   MeSH
• Anti-N-Methyl-D-Aspartate Receptor Encephalitis * cerebrospinal fluid   MeSH
• Humans MeSH
• Infant, Newborn MeSH
• Proteomics MeSH
• Retrospective Studies MeSH
• Sirtuin 2 MeSH
• Check Tag
• Humans MeSH
• Infant, Newborn MeSH
• Female MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH