Showing papers by "John Q. Trojanowski published in 2020"
Emory University1, Johns Hopkins University2, National Institutes of Health3, Stanford University4, University of Pennsylvania5, Arizona State University6, Icahn School of Medicine at Mount Sinai7, Veterans Health Administration8, Mayo Clinic9, University of Florida10, Pacific Northwest National Laboratory11, NewYork–Presbyterian Hospital12, Rush University Medical Center13, Baylor College of Medicine14
TL;DR: Large-scale, comprehensive proteomic profiling of Alzheimer’s disease brain and cerebrospinal fluid reveals disease-associated protein coexpression modules and highlights the importance of glia and energy metabolism in disease pathogenesis.
Abstract: Our understanding of Alzheimer's disease (AD) pathophysiology remains incomplete. Here we used quantitative mass spectrometry and coexpression network analysis to conduct the largest proteomic study thus far on AD. A protein network module linked to sugar metabolism emerged as one of the modules most significantly associated with AD pathology and cognitive impairment. This module was enriched in AD genetic risk factors and in microglia and astrocyte protein markers associated with an anti-inflammatory state, suggesting that the biological functions it represents serve a protective role in AD. Proteins from this module were elevated in cerebrospinal fluid in early stages of the disease. In this study of >2,000 brains and nearly 400 cerebrospinal fluid samples by quantitative proteomics, we identify proteins and biological processes in AD brains that may serve as therapeutic targets and fluid biomarkers for the disease.
472 citations
TL;DR: The evidence for cell-to-cell transmission of pathological proteins in neurodegenerative diseases such as Alzheimer disease and Parkinson disease is summarized, and key questions for future investigation are identified.
Abstract: Most neurodegenerative diseases are characterized by the intracellular or extracellular aggregation of misfolded proteins such as amyloid-β and tau in Alzheimer disease, α-synuclein in Parkinson disease, and TAR DNA-binding protein 43 in amyotrophic lateral sclerosis. Accumulating evidence from both human studies and disease models indicates that intercellular transmission and the subsequent templated amplification of these misfolded proteins are involved in the onset and progression of various neurodegenerative diseases. The misfolded proteins that are transferred between cells are referred to as ‘pathological seeds’. Recent studies have made exciting progress in identifying the characteristics of different pathological seeds, particularly those isolated from diseased brains. Advances have also been made in our understanding of the molecular mechanisms that regulate the transmission process, and the influence of the host cell on the conformation and properties of pathological seeds. The aim of this Review is to summarize our current knowledge of the cell-to-cell transmission of pathological proteins and to identify key questions for future investigation. In this Review, Peng et al. summarize the evidence for cell-to-cell transmission of pathological proteins in neurodegenerative diseases such as Alzheimer disease and Parkinson disease, and identify key questions for future investigation.
272 citations
TL;DR: Gene expression interrogation revealed that IFN pathway was grossly upregulated in clinical AD and significantly correlated with disease severity and complement activation, therefore, IFN constitutes a pivotal element within the neuroinflammatory network of AD and critically contributes to neuropathogenic processes.
Abstract: Type I interferon (IFN) is a key cytokine that curbs viral infection and cell malignancy. Previously, we demonstrated a potent IFN immunogenicity of nucleic acid-containing (NA-containing) amyloid fibrils in the periphery. Here, we investigated whether IFN is associated with β-amyloidosis inside the brain and contributes to neuropathology. An IFN-stimulated gene (ISG) signature was detected in the brains of multiple murine Alzheimer disease (AD) models, a phenomenon also observed in WT mouse brain challenged with generic NA-containing amyloid fibrils. In vitro, microglia innately responded to NA-containing amyloid fibrils. In AD models, activated ISG-expressing microglia exclusively surrounded NA+ amyloid β plaques, which accumulated in an age-dependent manner. Brain administration of rIFN-β resulted in microglial activation and complement C3-dependent synapse elimination in vivo. Conversely, selective IFN receptor blockade effectively diminished the ongoing microgliosis and synapse loss in AD models. Moreover, we detected activated ISG-expressing microglia enveloping NA-containing neuritic plaques in postmortem brains of patients with AD. Gene expression interrogation revealed that IFN pathway was grossly upregulated in clinical AD and significantly correlated with disease severity and complement activation. Therefore, IFN constitutes a pivotal element within the neuroinflammatory network of AD and critically contributes to neuropathogenic processes.
227 citations
Harvard University1, Translational Genomics Research Institute2, Mayo Clinic3, University of Miami4, UCL Institute of Neurology5, Columbia University Medical Center6, Rush University Medical Center7, Kaiser Permanente8, University of Washington9, University of Pittsburgh10, John P. Hussman Institute for Human Genomics11, Vanderbilt University12, Icahn School of Medicine at Mount Sinai13, Indiana University14, Boston University15, University of Pennsylvania16, Case Western Reserve University17, Columbia University18, Stanford University19
TL;DR: The impact of different APOE genotypes on Alzheimer’s dementia risk was greater than previously thought and APOE2 homozygotes had an exceptionally low risk.
Abstract: Each additional copy of the apolipoprotein E4 (APOE4) allele is associated with a higher risk of Alzheimer's dementia, while the APOE2 allele is associated with a lower risk of Alzheimer's dementia, it is not yet known whether APOE2 homozygotes have a particularly low risk. We generated Alzheimer's dementia odds ratios and other findings in more than 5,000 clinically characterized and neuropathologically characterized Alzheimer's dementia cases and controls. APOE2/2 was associated with a low Alzheimer's dementia odds ratios compared to APOE2/3 and 3/3, and an exceptionally low odds ratio compared to APOE4/4, and the impact of APOE2 and APOE4 gene dose was significantly greater in the neuropathologically confirmed group than in more than 24,000 neuropathologically unconfirmed cases and controls. Finding and targeting the factors by which APOE and its variants influence Alzheimer's disease could have a major impact on the understanding, treatment and prevention of the disease.
214 citations
University Health Network1, University of Toronto2, University of Pennsylvania3, University of Belgrade4, German Center for Neurodegenerative Diseases5, Technische Universität München6, Hannover Medical School7, University of California, San Diego8, Ludwig Maximilian University of Munich9, University of Barcelona10, Medical University of Vienna11, Erasmus University Rotterdam12, King's College London13
TL;DR: Defining cell-specific stages of tau pathology helps to identify preclinical or early-stage cases for the better understanding of early pathogenic events, has implications for understanding the clinical subtype-specific dynamics of disease-propagation, and informs tau-neuroimaging on distribution patterns.
Abstract: Progressive supranuclear palsy (PSP) is a 4R-tauopathy predominated by subcortical pathology in neurons, astrocytes, and oligodendroglia associated with various clinical phenotypes. In the present international study, we addressed the question of whether or not sequential distribution patterns can be recognized for PSP pathology. We evaluated heat maps and distribution patterns of neuronal, astroglial, and oligodendroglial tau pathologies and their combinations in different clinical subtypes of PSP in postmortem brains. We used conditional probability and logistic regression to model the sequential distribution of tau pathologies across different brain regions. Tau pathology uniformly predominates in the neurons of the pallido-nigro-luysian axis in different clinical subtypes. However, clinical subtypes are distinguished not only by total tau load but rather cell-type (neuronal versus glial) specific vulnerability patterns of brain regions suggesting distinct dynamics or circuit-specific segregation of propagation of tau pathologies. For Richardson syndrome (n = 81) we recognize six sequential steps of involvement of brain regions by the combination of cellular tau pathologies. This is translated to six stages for the practical neuropathological diagnosis by the evaluation of the subthalamic nucleus, globus pallidus, striatum, cerebellum with dentate nucleus, and frontal and occipital cortices. This system can be applied to further clinical subtypes by emphasizing whether they show caudal (cerebellum/dentate nucleus) or rostral (cortical) predominant, or both types of pattern. Defining cell-specific stages of tau pathology helps to identify preclinical or early-stage cases for the better understanding of early pathogenic events, has implications for understanding the clinical subtype-specific dynamics of disease-propagation, and informs tau-neuroimaging on distribution patterns.
168 citations
TL;DR: It is suggested that Alzheimer’s disease involves a reconfiguration of the epigenome, where H3K27ac and H3k9ac impact disease pathways by dysregulating transcription- and chromatin-gene feedback loops and highlights potential epigenetic strategies for early-stage disease treatment.
Abstract: Protein aggregation is the hallmark of neurodegeneration, but the molecular mechanisms underlying late-onset Alzheimer's disease (AD) are unclear. Here we integrated transcriptomic, proteomic and epigenomic analyses of postmortem human brains to identify molecular pathways involved in AD. RNA sequencing analysis revealed upregulation of transcription- and chromatin-related genes, including the histone acetyltransferases for H3K27ac and H3K9ac. An unbiased proteomic screening singled out H3K27ac and H3K9ac as the main enrichments specific to AD. In turn, epigenomic profiling revealed gains in the histone H3 modifications H3K27ac and H3K9ac linked to transcription, chromatin and disease pathways in AD. Increasing genome-wide H3K27ac and H3K9ac in a fly model of AD exacerbated amyloid-β42-driven neurodegeneration. Together, these findings suggest that AD involves a reconfiguration of the epigenome, wherein H3K27ac and H3K9ac affect disease pathways by dysregulating transcription- and chromatin-gene feedback loops. The identification of this process highlights potential epigenetic strategies for early-stage disease treatment.
146 citations
TL;DR: How dysfunctional pericytes contribute to the pathogenesis of vascular cognitive impairment including cerebral ‘small vessel’ and ‘large vessel” diseases, as well as AD is focused on.
Abstract: Pericytes are unique, multi-functional mural cells localized at the abluminal side of the perivascular space in microvessels. Originally discovered in 19th century, pericytes had drawn less attention until decades ago mainly due to lack of specific markers. Recently, however, a growing body of evidence has revealed that pericytes play various important roles: development and maintenance of blood-brain barrier (BBB), regulation of the neurovascular system (e.g., vascular stability, vessel formation, cerebral blood flow, etc.), trafficking of inflammatory cells, clearance of toxic waste products from the brain, and acquisition of stem cell-like properties. In the neurovascular unit, pericytes perform these functions through coordinated crosstalk with neighboring cells including endothelial, glial, and neuronal cells. Dysfunction of pericytes contribute to a wide variety of diseases that lead to cognitive impairments such as cerebral small vessel disease (SVD), acute stroke, Alzheimer's disease (AD), and other neurological disorders. For instance, in SVDs, pericyte degeneration leads to microvessel instability and demyelination while in stroke, pericyte constriction after ischemia causes a no-reflow phenomenon in brain capillaries. In AD, which shares some common risk factors with vascular dementia, reduction in pericyte coverage and subsequent microvascular impairments are observed in association with white matter attenuation and contribute to impaired cognition. Pericyte loss causes BBB-breakdown, which stagnates amyloid β clearance and the leakage of neurotoxic molecules into the brain parenchyma. In this review, we first summarize the characteristics of brain microvessel pericytes, and their roles in the central nervous system. Then, we focus on how dysfunctional pericytes contribute to the pathogenesis of vascular cognitive impairment including cerebral 'small vessel' and 'large vessel' diseases, as well as AD. Finally, we discuss therapeutic implications for these disorders by targeting pericytes.
123 citations
TL;DR: These findings suggest a "feed-forward" mechanism whereby Aβ plaques enhance endogenous α-syn seeding and spreading over time post-injection with mpffs, and hyperphosphorylated tau (p-tau) was induced in α- syn mpff-injected 5xFAD mice.
113 citations
TL;DR: A new transgenic mouse line is generated expressing 6 human tau isoforms with equal 3R and 4R ratios, recapitulate distinct human t Tau strains in mouse brains with similar isoform compositions and cell type specificities, and further show the strain transmission pattern is independent of its isoform composition.
Abstract: The deposition of pathological tau is a common feature in several neurodegenerative tauopathies. Although equal ratios of tau isoforms with 3 (3R) and 4 (4R) microtubule-binding repeats are expressed in the adult human brain, the pathological tau from different tauopathies have distinct isoform compositions and cell type specificities. The underlying mechanisms of tauopathies are unknown, partially due to the lack of proper models. Here, we generate a new transgenic mouse line expressing equal ratios of 3R and 4R human tau isoforms (6hTau mice). Intracerebral injections of distinct human tauopathy brain-derived tau strains into 6hTau mice recapitulate the deposition of pathological tau with distinct tau isoform compositions and cell type specificities as in human tauopathies. Moreover, through in vivo propagation of these tau strains among different mouse lines, we demonstrate that the transmission of distinct tau strains is independent of strain isoform compositions, but instead intrinsic to unique pathological conformations.
95 citations
Duke University1, Indiana University2, Baker IDI Heart and Diabetes Institute3, University of Arizona4, University of Texas Health Science Center at San Antonio5, University of Pennsylvania6, Edith Cowan University7, Macquarie University8, University of California, San Francisco9, Mayo Clinic10, Houston Methodist Hospital11, Rush University Medical Center12, Cornell University13
TL;DR: How sex and APOE ε4 genotype modify the association between Alzheimer’s disease biomarkers and metabolites in serum is investigated to suggest that females experience greater impairment of mitochondrial energy production than males.
Abstract: Late-onset Alzheimer's disease (AD) can, in part, be considered a metabolic disease. Besides age, female sex and APOE e4 genotype represent strong risk factors for AD that also give rise to large metabolic differences. We systematically investigated group-specific metabolic alterations by conducting stratified association analyses of 139 serum metabolites in 1,517 individuals from the AD Neuroimaging Initiative with AD biomarkers. We observed substantial sex differences in effects of 15 metabolites with partially overlapping differences for APOE e4 status groups. Several group-specific metabolic alterations were not observed in unstratified analyses using sex and APOE e4 as covariates. Combined stratification revealed further subgroup-specific metabolic effects limited to APOE e4+ females. The observed metabolic alterations suggest that females experience greater impairment of mitochondrial energy production than males. Dissecting metabolic heterogeneity in AD pathogenesis can therefore enable grading the biomedical relevance for specific pathways within specific subgroups, guiding the way to personalized medicine.
86 citations
Northwestern University1, University of Iowa2, University of Pennsylvania3, National Institutes of Health4, University of Southern California5, University of California, San Diego6, Indiana University – Purdue University Indianapolis7, University of California, San Francisco8, Stanford University9, University of Göttingen10, University of Rochester Medical Center11, University of Pittsburgh12, Michael J. Fox Foundation13, Icahn School of Medicine at Mount Sinai14
TL;DR: The authors' data show evidence of subtle motor and non-motor signs of Parkinson's disease in non-manifesting carriers compared with healthy controls that can precede DAT deficit.
Abstract: Summary Background The Parkinson's Progression Markers Initiative (PPMI) is an ongoing observational, longitudinal cohort study of participants with Parkinson's disease, healthy controls, and carriers of the most common Parkinson's disease-related genetic mutations, which aims to define biomarkers of Parkinson's disease diagnosis and progression. All participants are assessed annually with a battery of motor and non-motor scales, 123-I Ioflupane dopamine transporter (DAT) imaging, and biological variables. We aimed to examine whether non-manifesting carriers of LRRK2 and GBA mutations have prodromal features of Parkinson's disease that correlate with reduced DAT binding. Methods This cross-sectional analysis is based on assessments done at enrolment in the subset of non-manifesting carriers of LRRK2 and GBA mutations enrolled into the PPMI study from 33 participating sites worldwide. The primary objective was to examine baseline clinical and DAT imaging characteristics in non-manifesting carriers with GBA and LRRK2 mutations compared with healthy controls. DAT deficit was defined as less than 65% of putamen striatal binding ratio expected for the individual's age. We used t tests, χ2 tests, and Fisher's exact tests to compare baseline demographics across groups. An inverse probability weighting method was applied to control for potential confounders such as age and sex. To account for multiple comparisons, we applied a family-wise error rate to each set of analyses. This study is registered with ClinicalTrials.gov , number NCT01141023 . Findings Between Jan 1, 2014, and Jan 1, 2019, the study enrolled 208 LRRK2 (93% G2019S) and 184 GBA (96% N370S) non-manifesting carriers. Both groups were similar with respect to mean age, and about 60% were female. Of the 286 (73%) non-manifesting carriers that had DAT imaging results, 18 (11%) LRRK2 and four (3%) GBA non-manifesting carriers had a DAT deficit. Compared with healthy controls, both LRRK2 and GBA non-manifesting carriers had significantly increased mean scores on the Movement Disorders Society Unified Parkinson's Disease Rating Scale (total score 4·6 [SD 4·4] healthy controls vs 8·4 [7·3] LRRK2 vs 9·5 [9·2] GBA, p Interpretation Our data show evidence of subtle motor and non-motor signs of Parkinson's disease in non-manifesting carriers compared with healthy controls that can precede DAT deficit. Longitudinal data will be essential to confirm these findings and define the trajectory and predictors for development of Parkinson's disease. Funding Michael J Fox Foundation for Parkinson's Research.
TL;DR: The background and recent findings underpinning these concepts with a focus on two major pathological proteins: tau and α-synuclein are summarized and their clinical implications for tauopathies and synucleinopathies are discussed.
TL;DR: This study systematically examines the relationship between GCase activity and both pathogenic and non-pathogenic forms of α-synuclein in primary hippocampal, cortical, and midbrain neuron and astrocyte cultures, as well as in transgenic mice and a non-transgenic mouse model of PD.
Mayo Clinic1, University of California, San Francisco2, Case Western Reserve University3, University of California, Los Angeles4, University of Pennsylvania5, University of Washington6, Harvard University7, Indiana University – Purdue University Indianapolis8, University of North Carolina at Chapel Hill9, Johns Hopkins University10, University of Toronto11, Washington University in St. Louis12, Columbia University13, Northwestern University14, University of British Columbia15, University of Texas Southwestern Medical Center16, University of California, San Diego17, University of Alabama at Birmingham18, University of Southern California19
TL;DR: Global rating scoring rules for the CDR® plus NACC FTLD to detect and track early frontotemporal lobar degeneration (FTLD) and to conduct clinical trials in FTLD are created.
Abstract: Author(s): Miyagawa, Toji; Brushaber, Danielle; Syrjanen, Jeremy; Kremers, Walter; Fields, Julie; Forsberg, Leah K; Heuer, Hilary W; Knopman, David; Kornak, John; Boxer, Adam; Rosen, Howard J; Boeve, Bradley F; Appleby, Brian; Bordelon, Yvette; Bove, Jessica; Brannelly, Patrick; Caso, Christina; Coppola, Giovanni; Dever, Reilly; Dheel, Christina; Dickerson, Bradford; Dickinson, Susan; Dominguez, Sophia; Domoto-Reilly, Kimiko; Faber, Kelley; Ferrell, Jessica; Fishman, Ann; Fong, Jamie; Foroud, Tatiana; Gavrilova, Ralitza; Gearhart, Debra; Ghazanfari, Behnaz; Ghoshal, Nupur; Goldman, Jill S; Graff-Radford, Jonathan; Graff-Radford, Neill; Grant, Ian; Grossman, Murray; Haley, Dana; Hsiung, Robin; Huey, Edward; Irwin, David; Jones, David; Jones, Lynne; Kantarci, Kejal; Karydas, Anna; Kaufer, Daniel; Kerwin, Diana; Kraft, Ruth; Kramer, Joel; Kukull, Walter; Litvan, Irene; Lucente, Diane; Lungu, Codrin; Mackenzie, Ian; Maldonado, Miranda; Manoochehri, Masood; McGinnis, Scott; McKinley, Emily; Mendez, Mario F; Miller, Bruce; Multani, Namita; Onyike, Chiadi; Padmanabhan, Jaya; Pantelyat, Alexander; Pearlman, Rodney; Petrucelli, Leonard; Potter, Madeline; Rademakers, Rosa; Ramos, Eliana M; Rankin, Kate; Rascovsky, Katya; Roberson, Erik D; Rogalski, Emily; Sengdy, Pheth; Shaw, Leslie; Tartaglia, Maria C; Tatton, Nadine; Taylor, Joanne; Toga, Arthur; Trojanowski, John Q; Wang, Ping; Weintraub, Sandra; Wong, Bonnie; Wszolek, Zbigniew | Abstract: IntroductionWe created global rating scoring rules for the CDR® plus NACC FTLD to detect and track early frontotemporal lobar degeneration (FTLD) and to conduct clinical trials in FTLD.MethodsThe CDR plus NACC FTLD rating was applied to 970 sporadic and familial participants from the baseline visit of Advancing Research and Treatment in Frontotemporal Lobar Degeneration (ARTFL)/Longitudinal Evaluation of Familial Frontotemporal Dementia Subjects (LEFFTDS). Each of the eight domains of the CDR plus NACC FTLD was equally weighed in determining the global score. An interrater reliability study was completed for 40 participants.ResultsThe CDR plus NACC FTLD showed very good interrater reliability. It was especially useful in detecting clinical features of mild non-fluent/agrammatic variant primary progressive aphasia participants.DiscussionThe global CDR plus NACC FTLD score could be an attractive outcome measure for clinical trials in symptomatic FTLD, and may be useful in natural history studies and clinical trials in FTLD spectrum disorders.
TL;DR: Higher microglia activation as determined by CSF sTREM2 ormicroglia PET shows protective effects on subsequent amyloid accumulation, as well as a two‐pronged translational approach to address this question.
Abstract: Microglia activation is the brain's major immune response to amyloid plaques in Alzheimer's disease (AD). Both cerebrospinal fluid (CSF) levels of soluble TREM2 (sTREM2), a biomarker of microglia activation, and microglia PET are increased in AD; however, whether an increase in these biomarkers is associated with reduced amyloid-beta (Aβ) accumulation remains unclear. To address this question, we pursued a two-pronged translational approach. Firstly, in non-demented and demented individuals, we tested CSF sTREM2 at baseline to predict (i) amyloid PET changes over ∼2 years and (ii) tau PET cross-sectionally assessed in a subset of patients. We found higher CSF sTREM2 associated with attenuated amyloid PET increase and lower tau PET. Secondly, in the AppNL-G-F mouse model of amyloidosis, we studied baseline 18 F-GE180 microglia PET and longitudinal amyloid PET to test the microglia vs. Aβ association, without any confounding co-pathologies often present in AD patients. Higher microglia PET at age 5 months was associated with a slower amyloid PET increase between ages 5-to-10 months. In conclusion, higher microglia activation as determined by CSF sTREM2 or microglia PET shows protective effects on subsequent amyloid accumulation.
TL;DR: This study shows glial tau pathology can propagate in the absence of neuronal tau, and in particular, oligodendrocytes transmit t Tau pathology via their own processes, independent of neurons.
Abstract: Tauopathies are characterized by abnormal accumulation of tau protein in neurons and glia. In Alzheimer's disease (AD), tau aggregates in neurons, while in corticobasal degeneration (CBD) and progressive supranuclear palsy (PSP), tau also aggregates in astrocytes and oligodendrocytes. We previously demonstrated that human CBD and PSP tauopathy lysates (CBD-tau and PSP-tau) contain distinct tau strains that propagate neuronal and glial tau aggregates in nontransgenic (nonTg) mouse brain. Yet the mechanism of glial tau transmission is unknown. Here, we developed a novel mouse model to knock down tau in neurons to test for glial tau transmission. While oligodendroglial tau pathology propagated across the mouse brain in the absence of neuronal tau pathology, astrocytic tau pathology did not. Oligodendroglial tau aggregates propagated along white matter tracts independently of neuronal axons, and resulted in oligodendrocyte cell loss. Thus, glial tau pathology has significant functional consequences independent of neuronal tau pathology.
University of Pennsylvania1, University of Iowa2, Inha University3, Northwestern University4, Indiana University – Purdue University Indianapolis5, University of Southern California6, University of California, San Francisco7, University of Rochester Medical Center8, University of Pittsburgh9, Michael J. Fox Foundation10, Veterans Health Administration11, University of Göttingen12, University of San Diego13
TL;DR: In this paper, the authors analyzed the longitudinal profile of Alzheimer's disease (AD) cerebrospinal fluid (CSF) biomarkers in early Parkinson's disease compared with healthy controls (HCs) and tested baseline CSF biomarkers for prediction of clinical decline in PD.
Abstract: Author(s): Irwin, David J; Fedler, Janel; Coffey, Christopher S; Caspell-Garcia, Chelsea; Kang, Ju Hee; Simuni, Tanya; Foroud, Tatiana; Toga, Arthur W; Tanner, Caroline M; Kieburtz, Karl; Chahine, Lana M; Reimer, Alyssa; Hutten, Samantha; Weintraub, Daniel; Mollenhauer, Brit; Galasko, Douglas R; Siderowf, Andrew; Marek, Kenneth; Trojanowski, John Q; Shaw, Leslie M; Parkinson's Progression Marker Initiative | Abstract: ObjectiveWe analyzed the longitudinal profile of Alzheimer's disease (AD) cerebrospinal fluid (CSF) biomarkers in early Parkinson's disease (PD) compared with healthy controls (HCs) and tested baseline CSF biomarkers for prediction of clinical decline in PD.MethodsAmyloid-β 1 to 42 (Aβ42 ), total tau (t-tau) and phosphorylated tau (p-tau) at the threonine 181 position were measured using the high-precision Roche Elecsys electrochemiluminescence immunoassay in all available CSF samples from longitudinally studied patients with PD (n = 416) and HCs (n = 192) followed for up to 3 years in the Parkinson's Progression Markers Initiative (PPMI). Longitudinal CSF and clinical data were analyzed with linear-mixed effects models.ResultsWe found patients with PD had lower CSF t-tau (median = 157.7 pg/mL; range = 80.9-467.0); p-tau (median = 13.4 pg/mL; range = 8.0-40.1), and Aβ42 (median = 846.2 pg/mL; range = 238.8-3,707.0) than HCs at baseline (CSF t-tau median = 173.5 pg/mL; range = 82.0-580.8; p-tau median = 15.4 pg/mL; range = 8.1-73.6; and Aβ42 median = 926.5 pg/mL; range = 239.1-3,297.0; p l 0.05-0.001) and a moderate-to-strong correlation among these biomarkers in both patients with PD and HCs (Rho = 0.50-0.97; p l 0.001). Of the patients with PD, 31.5% had pathologically low levels of CSF Aβ42 at baseline and these patients with PD had lower p-tau levels (median = 10.8 pg/mL; range = 8.0-32.8) compared with 27.7% of HCs with pathologically low CSF Aβ42 (CSF p-tau median = 12.8 pg/mL; range 8.2-73.6; p l 0.03). In longitudinal CSF analysis, we found patients with PD had greater decline in CSF Aβ42 (mean difference = -41.83 pg/mL; p = 0.03) and CSF p-tau (mean difference = -0.38 pg/mL; p = 0.03) at year 3 compared with HCs. Baseline CSF Aβ42 values predicted small but measurable decline on cognitive, autonomic, and motor function in early PD.InterpretationOur data suggest baseline CSF AD biomarkers may have prognostic value in early PD and that the dynamic change of these markers, although modest over a 3-year period, suggest biomarker profiles in PD may deviate from healthy aging. ANN NEUROL 2020;88:574-587.
TL;DR: Astroglial and neurofibrillary tau pathologies of CTE are phenotypically distinct from each other and recapitulate the tau immunophenotypes encountered in ageing and Alzheimer's disease, establishing that the immunohistochemical distinction of Cte neuropathology from other mixed 3R/4R tauopathies of Alzheimer's Disease and ageing may rest solely on the pattern and distribution of pathology.
Abstract: Traumatic brain injury (TBI) is a risk factor for neurodegenerative disease, including chronic traumatic encephalopathy (CTE). Preliminary consensus criteria define the pathognomonic lesion of CTE as patchy tau pathology within neurons and astrocytes at the depths of cortical sulci. However, the specific tau isoform composition and post-translational modifications in CTE remain largely unexplored. Using immunohistochemistry, we performed tau phenotyping of CTE neuropathologies and compared this to a range of tau pathologies, including Alzheimer’s disease, primary age-related tauopathy, ageing-related tau astrogliopathy and multiple subtypes of frontotemporal lobar degeneration with tau inclusions. Cases satisfying preliminary consensus diagnostic criteria for CTE neuropathological change (CTE-NC) were identified (athletes, n = 10; long-term survivors of moderate or severe TBI, n = 4) from the Glasgow TBI Archive and Penn Neurodegenerative Disease Brain Bank. In addition, material from a range of autopsy-proven ageing-associated and primary tauopathies in which there was no known history of exposure to TBI was selected as non-injured controls (n = 32). Each case was then stained with a panel of tau antibodies specific for phospho-epitopes (PHF1, CP13, AT100, pS262), microtubule-binding repeat domains (3R, 4R), truncation (Tau-C3) or conformation (GT-7, GT-38) and the extent and distribution of staining assessed. Cell types were confirmed with double immunofluorescent labelling. Results demonstrate that astroglial tau pathology in CTE is composed of 4R-immunoreactive thorn-shaped astrocytes, echoing the morphology and immunophenotype of astrocytes encountered in ageing-related tau astrogliopathy. In contrast, neurofibrillary tangles of CTE contain both 3R and 4R tau, with post-translational modifications and conformations consistent with Alzheimer’s disease and primary age-related tauopathy. Our observations establish that the astroglial and neurofibrillary tau pathologies of CTE are phenotypically distinct from each other and recapitulate the tau immunophenotypes encountered in ageing and Alzheimer’s disease. As such, the immunohistochemical distinction of CTE neuropathology from other mixed 3R/4R tauopathies of Alzheimer’s disease and ageing may rest solely on the pattern and distribution of pathology.
Northwestern University1, University of Iowa2, University of Pennsylvania3, Columbia University4, National Institutes of Health5, University of Southern California6, University of California, San Diego7, Indiana University – Purdue University Indianapolis8, University of California, San Francisco9, Stanford University10, University of Göttingen11, University of Rochester Medical Center12, University of Pittsburgh13, Michael J. Fox Foundation14, Icahn School of Medicine at Mount Sinai15
TL;DR: There are limited data on the phenotypic and dopamine transporter (DAT) imaging characterization of the Parkinson's disease patients with leucine rich kinase 2 (LRRK2) and glucosylceramidase beta (GBA) mutations.
Abstract: Background There are limited data on the phenotypic and dopamine transporter (DAT) imaging characterization of the Parkinson's disease (PD) patients with leucine rich kinase 2 (LRRK2) and glucosylceramidase beta (GBA) mutations. Objective The objective of this study was to examine baseline clinical and DAT imaging characteristics in GBA and LRRK2 mutation carriers with early PD compared with sporadic PD. Methods The Parkinson's Progression Markers Initiative is an ongoing observational longitudinal study that enrolled participants with sporadic PD, LRRK2 and GBA PD carriers from 33 sites worldwide. All participants are assessed annually with a battery of motor and nonmotor scales, 123-I Ioflupane DAT imaging, and biologic variables. Results We assessed 158 LRRK2 (89% G2019S), 80 GBA (89 %N370S), and 361 sporadic PD participants with the mean (standard deviation) disease duration of 2.9 (1.9), 3.1 (2.0), and 2.6 (0.6) years, respectively. When compared with sporadic PD, the GBA PD patients had no difference in any motor, cognitive, or autonomic features. The LRRK2 PD patients had less motor disability and lower rapid eye movement behavior disorder questionnaire scores, but no meaningful difference in cognitive or autonomic features. Both genetic cohorts had a higher score on the impulse control disorders scale when compared with sporadic PD, but no difference in other psychiatric features. Both genetic PD cohorts had less loss of dopamine transporter on DAT imaging when compared with sporadic PD. Conclusions We confirm previous reports of milder phenotype associated with LRRK2-PD. A previously reported more aggressive phenotype in GBA-PD is not evident early in the disease in N370s carriers. This observation identifies a window for potential disease-modifying interventions. Longitudinal data will be essential to define the slope of progression for both genetic cohorts. Trial registration ClinicalTrials.gov (NCT01141023). © 2020 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society.
Mayo Clinic1, University of California, San Francisco2, Case Western Reserve University3, University of California, Los Angeles4, University of Pennsylvania5, University of Washington6, Harvard University7, Indiana University – Purdue University Indianapolis8, University of North Carolina at Chapel Hill9, Johns Hopkins University10, University of Toronto11, Washington University in St. Louis12, Columbia University13, Northwestern University14, University of British Columbia15, University of California, San Diego16, University of Alabama at Birmingham17
TL;DR: Behavior/Comportment/Personality (BEHAV) and Language (LANG) domains were added to the Clinical Dementia Rating for improving evaluation of patients with frontotemporal lobar degeneration (FTLD) (CDR® plus NACC FTLD).
Abstract: Introduction Behavior/Comportment/Personality (BEHAV) and Language (LANG) domains were added to the Clinical Dementia Rating (CDR®) for improving evaluation of patients with frontotemporal lobar degeneration (FTLD) (CDR® plus NACC FTLD). Methods We analyzed the CDR® plus NACC FTLD among participants from the baseline visit of the Advancing Research and Treatment for Frontotemporal Lobar Degeneration/Longitudinal Evaluation of Familial Frontotemporal Dementia Subjects Consortium. Results The CDR® plus NACC FTLD was able to detect early symptoms in the mildly impaired participants who were rated as CDR® sum of boxes (CDR®-SB) = 0. The CDR®-SB was not sensitive, particularly in participants with mild nonfluent/agrammatic primary progressive aphasia. Participants with familial and sporadic behavioral variant FTD exhibited similar CDR® plus NACC FTLD profiles except that language impairment was more frequent in participants with mild sporadic behavioral variant FTD. Adding the BEHAV and/or LANG domains to the CDR®-SB significantly enhanced discriminatory power in differentiating among the FTLD spectrum disorders. Discussion The BEHAV and LANG domains enable the CDR® plus NACC FTLD to capture early symptomatology of FTLD.
TL;DR: It is unclear how different proteinopathies (tau, transactive response DNA‐binding protein 43 [TDP‐43], amyloid β [Aβ], and α‐synuclein) contribute to atrophy within medial temporal lobe (MTL) subregions in Alzheimer's disease (AD).
Abstract: Introduction It is unclear how different proteinopathies (tau, transactive response DNA-binding protein 43 [TDP-43], amyloid β [Aβ], and α-synuclein) contribute to atrophy within medial temporal lobe (MTL) subregions in Alzheimer's disease (AD). Methods We utilized antemortem structural magnetic resonance imaging (MRI) data to measure MTL substructures and examined the relative contribution of tau, TDP-43, Aβ, and α-synuclein measured in post-mortem tissue from 92 individuals with intermediate to high AD neuropathology. Receiver-operating characteristic (ROC) curves were analyzed for each subregion in order to discriminate TDP-43-negative and TDP-43-positive patients. Results TDP-43 was strongly associated with anterior MTL regions, whereas tau was relatively more associated with the posterior hippocampus. Among the MTL regions, the anterior hippocampus showed the highest area under the ROC curve (AUC). Discussion We found specific contributions of different pathologies on MTL substructure in this population with AD neuropathology. The anterior hippocampus may be a relevant region to detect concomitant TDP-43 pathology in the MTL of patients with AD.
TL;DR: A systematic functional genomic analysis in purified microglia and bulk tissue from mouse and human AD, FTD, and PSP uncovers a complex temporal trajectory of microglial-immune pathways involving the type 1 interferon response associated with tau pathology in the early stages, followed by later signatures of partial immune suppression and, subsequently, the type 2 interferons response.
University of California, Los Angeles1, Mayo Clinic2, Case Western Reserve University3, Harvard University4, University of Washington5, Indiana University – Purdue University Indianapolis6, University of California, San Francisco7, Washington University in St. Louis8, Columbia University9, Northwestern University10, University of Pennsylvania11, University of British Columbia12, University of North Carolina at Chapel Hill13, University of Texas Southwestern Medical Center14, University of California, San Diego15, Johns Hopkins University16, University of Alabama at Birmingham17, University of Toronto18
TL;DR: Two closely connected studies, involving multiple North American centers that evaluate both sporadic and familial frontotemporal dementia (FTD) participants and study longitudinal changes.
Abstract: Author(s): Ramos, Eliana Marisa; Dokuru, Deepika Reddy; Van Berlo, Victoria; Wojta, Kevin; Wang, Qing; Huang, Alden Y; Deverasetty, Sandeep; Qin, Yue; van Blitterswijk, Marka; Jackson, Jazmyne; Appleby, Brian; Bordelon, Yvette; Brannelly, Patrick; Brushaber, Danielle E; Dickerson, Bradford; Dickinson, Susan; Domoto-Reilly, Kimiko; Faber, Kelley; Fields, Julie; Fong, Jamie; Foroud, Tatiana; Forsberg, Leah K; Gavrilova, Ralitza; Ghoshal, Nupur; Goldman, Jill; Graff-Radford, Jonathan; Graff-Radford, Neill; Grant, Ian; Grossman, Murray; Heuer, Hilary W; Hsiung, Ging-Yuek R; Huey, Edward; Irwin, David; Kantarci, Kejal; Karydas, Anna; Kaufer, Daniel; Kerwin, Diana; Knopman, David; Kornak, John; Kramer, Joel H; Kremers, Walter; Kukull, Walter; Litvan, Irene; Ljubenkov, Peter; Lungu, Codrin; Mackenzie, Ian; Mendez, Mario F; Miller, Bruce L; Onyike, Chiadi; Pantelyat, Alexander; Pearlman, Rodney; Petrucelli, Len; Potter, Madeline; Rankin, Katherine P; Rascovsky, Katya; Roberson, Erik D; Rogalski, Emily; Shaw, Leslie; Syrjanen, Jeremy; Tartaglia, Maria Carmela; Tatton, Nadine; Taylor, Joanne; Toga, Arthur; Trojanowski, John Q; Weintraub, Sandra; Wong, Bonnie; Wszolek, Zbigniew; Rademakers, Rosa; Boeve, Brad F; Rosen, Howard J; Boxer, Adam L; ARTFL/LEFFTDS consortium; Coppola, Giovanni | Abstract: IntroductionThe Advancing Research and Treatment for Frontotemporal Lobar Degeneration (ARTFL) and Longitudinal Evaluation of Familial Frontotemporal Dementia Subjects (LEFFTDS) consortia are two closely connected studies, involving multiple North American centers that evaluate both sporadic and familial frontotemporal dementia (FTD) participants and study longitudinal changes.MethodsWe screened the major dementia-associated genes in 302 sporadic and 390 familial (symptomatic or at-risk) participants enrolled in these studies.ResultsAmong the sporadic patients, 16 (5.3%) carried chromosome 9 open reading frame 72 (C9orf72), microtubule-associated protein tau (MAPT), and progranulin (GRN) pathogenic variants, whereas in the familial series we identified 207 carriers from 146 families. Of interest, one patient was found to carry a homozygous C9orf72 expansion, while another carried both a C9orf72 expansion and a GRN pathogenic variant. We also identified likely pathogenic variants in the TAR DNA binding protein (TARDBP), presenilin 1 (PSEN1), and valosin containing protein (VCP) genes, and a subset of variants of unknown significance in other rare FTD genes.DiscussionOur study reports the genetic characterization of a large FTD series and supports an unbiased sequencing screen, irrespective of clinical presentation or family history.
TL;DR: This study shows that PUTG component scores were significantly associated with diagnostic group and AD biomarkers, a finding that was more pronounced in APOE ε4 carriers.
Abstract: Objective To investigate the association of triglyceride (TG) principal component scores with Alzheimer disease (AD) and the amyloid, tau, neurodegeneration, and cerebrovascular disease (A/T/N/V) biomarkers for AD. Methods Serum levels of 84 TG species were measured with untargeted lipid profiling of 689 participants from the Alzheimer9s Disease Neuroimaging Initiative cohort, including 190 cognitively normal older adults (CN), 339 with mild cognitive impairment (MCI), and 160 with AD. Principal component analysis with factor rotation was used for dimension reduction of TG species. Differences in principal components between diagnostic groups and associations between principal components and AD biomarkers (including CSF, MRI and [18F]fluorodeoxyglucose-PET) were assessed with a generalized linear model approach. In both cases, the Bonferroni method of adjustment was used to correct for multiple comparisons. Results The 84 TGs yielded 9 principal components, 2 of which, consisting of long-chain, polyunsaturated fatty acid–containing TGs (PUTGs), were significantly associated with MCI and AD. Lower levels of PUTGs were observed in MCI and AD compared to CN. PUTG principal component scores were also significantly associated with hippocampal volume and entorhinal cortical thickness. In participants carrying the APOE e4 allele, these principal components were significantly associated with CSF β-amyloid1–42 values and entorhinal cortical thickness. Conclusion This study shows that PUTG component scores were significantly associated with diagnostic group and AD biomarkers, a finding that was more pronounced in APOE e4 carriers. Replication in independent larger studies and longitudinal follow-up are warranted.
TL;DR: It is proposed that a HDAC6-dependent surveillance mechanism suppresses toxic tau accumulation, which may protect against the progression of AD and related tauopathies.
Abstract: Tauopathies including Alzheimer’s disease (AD) are marked by the accumulation of aberrantly modified tau proteins. Acetylated tau, in particular, has recently been implicated in neurodegeneration and cognitive decline. HDAC6 reversibly regulates tau acetylation, but its role in tauopathy progression remains unclear. Here, we identified an HDAC6-chaperone complex that targets aberrantly modified tau. HDAC6 not only deacetylates tau but also suppresses tau hyperphosphorylation within the microtubule-binding region. In neurons and human AD brain, HDAC6 becomes co-aggregated within focal tau swellings and human AD neuritic plaques. Using mass spectrometry, we identify a novel HDAC6-regulated tau acetylation site as a disease specific marker for 3R/4R and 3R tauopathies, supporting uniquely modified tau species in different neurodegenerative disorders. Tau transgenic mice lacking HDAC6 show reduced survival characterized by accelerated tau pathology and cognitive decline. We propose that a HDAC6-dependent surveillance mechanism suppresses toxic tau accumulation, which may protect against the progression of AD and related tauopathies. HDAC6 is a tau deacetylase and acetylation of tau inhibits its function and promotes aggregation. Here the authors show that HDAC6 protects against tau accumulation in a mouse model of tauopathy.
TL;DR: In most cases, severe LATE-NC and FTLD-TDP can be differentiated by applying simple neuropathological criteria, and another proposed neuro Pathological feature related to TDP-43 proteinopathy in aged individuals is 'Alpha' versus 'Beta' in amygdala.
Abstract: TAR-DNA binding protein-43 (TDP-43) proteinopathy is seen in multiple brain diseases. A standardized terminology was recommended recently for common age-related TDP-43 proteinopathy: limbic-predominant, age-related TDP-43 encephalopathy (LATE) and the underlying neuropathological changes, LATE-NC. LATE-NC may be co-morbid with Alzheimer's disease neuropathological changes (ADNC). However, there currently are ill-defined diagnostic classification issues among LATE-NC, ADNC, and frontotemporal lobar degeneration with TDP-43 (FTLD-TDP). A practical challenge is that different autopsy cohorts are composed of disparate groups of research volunteers: hospital- and clinic-based cohorts are enriched for FTLD-TDP cases, whereas community-based cohorts have more LATE-NC cases. Neuropathological methods also differ across laboratories. Here, we combined both cases and neuropathologists' diagnoses from two research centres-University of Pennsylvania and University of Kentucky. The study was designed to compare neuropathological findings between FTLD-TDP and pathologically severe LATE-NC. First, cases were selected from the University of Pennsylvania with pathological diagnoses of either FTLD-TDP (n = 33) or severe LATE-NC (mostly stage 3) with co-morbid ADNC (n = 30). Sections from these University of Pennsylvania cases were cut from amygdala, anterior cingulate, superior/mid-temporal, and middle frontal gyrus. These sections were stained for phospho-TDP-43 immunohistochemically and evaluated independently by two University of Kentucky neuropathologists blinded to case data. A simple set of criteria hypothesized to differentiate FTLD-TDP from LATE-NC was generated based on density of TDP-43 immunoreactive neuronal cytoplasmic inclusions in the neocortical regions. Criteria-based sensitivity and specificity of differentiating severe LATE-NC from FTLD-TDP cases with blind evaluation was ∼90%. Another proposed neuropathological feature related to TDP-43 proteinopathy in aged individuals is 'Alpha' versus 'Beta' in amygdala. Alpha and Beta status was diagnosed by neuropathologists from both universities (n = 5 raters). There was poor inter-rater reliability of Alpha/Beta classification (mean κ = 0.31). We next tested a separate cohort of cases from University of Kentucky with either FTLD-TDP (n = 8) or with relatively 'pure' severe LATE-NC (lacking intermediate or severe ADNC; n = 14). The simple criteria were applied by neuropathologists blinded to the prior diagnoses at University of Pennsylvania. Again, the criteria for differentiating LATE-NC from FTLD-TDP was effective, with sensitivity and specificity ∼90%. If more representative cases from each cohort (including less severe TDP-43 proteinopathy) had been included, the overall accuracy for identifying LATE-NC was estimated at >98% for both cohorts. Also across both cohorts, cases with FTLD-TDP died younger than those with LATE-NC (P < 0.0001). We conclude that in most cases, severe LATE-NC and FTLD-TDP can be differentiated by applying simple neuropathological criteria.
Nicolai Franzmeier1, M. Suárez-Calvet2, Lukas Frontzkowski1, Annah M. Moore3 +220 more•Institutions (5)
TL;DR: A higher CSF sTREM2 levels are associated with attenuated ApoE4-related risk for future cognitive decline and AD-typical neurodegeneration, providing further evidence that TREM2 may be protective against the development of AD.
Abstract: The Apolipoprotein E e4 allele (i.e. ApoE4) is the strongest genetic risk factor for sporadic Alzheimer’s disease (AD). TREM2 (i.e. Triggering receptor expressed on myeloid cells 2) is a microglial transmembrane protein brain that plays a central role in microglia activation in response to AD brain pathologies. Whether higher TREM2-related microglia activity modulates the risk to develop clinical AD is an open question. Thus, the aim of the current study was to assess whether higher sTREM2 attenuates the effects of ApoE4-effects on future cognitive decline and neurodegeneration. We included 708 subjects ranging from cognitively normal (CN, n = 221) to mild cognitive impairment (MCI, n = 414) and AD dementia (n = 73) from the Alzheimer’s disease Neuroimaging Initiative. We used linear regression to test the interaction between ApoE4-carriage by CSF-assessed sTREM2 levels as a predictor of longitudinally assessed cognitive decline and MRI-assessed changes in hippocampal volume changes (mean follow-up of 4 years, range of 1.7-7 years). Across the entire sample, we found that higher CSF sTREM2 at baseline was associated with attenuated effects of ApoE4-carriage (i.e. sTREM2 x ApoE4 interaction) on longitudinal global cognitive (p = 0.001, Cohen’s f2 = 0.137) and memory decline (p = 0.006, Cohen’s f2 = 0.104) as well as longitudinally assessed hippocampal atrophy (p = 0.046, Cohen’s f2 = 0.089), independent of CSF markers of primary AD pathology (i.e. Aβ1–42, p-tau181). While overall effects of sTREM2 were small, exploratory subanalyses stratified by diagnostic groups showed that beneficial effects of sTREM2 were pronounced in the MCI group. Our results suggest that a higher CSF sTREM2 levels are associated with attenuated ApoE4-related risk for future cognitive decline and AD-typical neurodegeneration. These findings provide further evidence that TREM2 may be protective against the development of AD.
TL;DR: The intact Sigma-2 receptor complex may potentially be a novel pharmacological target to decrease neuronal Aβ42 internalization and accumulation, which may represent a new strategy for inhibiting the rate of neurotoxicity, neurodegeneration, and progression of AD.
Abstract: Our lab has recently shown that the Sigma-2 Receptor/Transmembrane Protein 97 (TMEM97) and Progesterone Receptor Membrane Component 1 (PGRMC1) form a complex with the Low Density Lipoprotein Receptor (LDLR), and this intact complex is required for efficient uptake of lipoproteins such as LDL and apolipoprotein E (apoE) These receptors are expressed in the nervous system where they have implications in neurodegenerative diseases such as Alzheimer's disease (AD), where apoE is involved in neuronal uptake and accumulation of Aβ42, eventually cascading into neurodegeneration, synaptic dysfunction, and ultimately, dementia We hypothesize that the intact Sigma-2 receptor complex-TMEM97, PGRMC1, and LDLR-is necessary for internalization of apoE and Aβ42 monomers (mAβ42) and oligomers (oAβ42), and the disruption of the receptor complex inhibits uptake The results of this study suggest that the intact Sigma-2 receptor complex is a binding site for mAβ42 and oAβ42, in the presence or absence of apoE2, apoE3, and apoE4 The loss or pharmacological inhibition of one or both of these proteins results in the disruption of the complex leading to decreased uptake of mAβ42 and oAβ42 and apoE in primary neurons The TMEM97, PGRMC1, and LDLR complex is a pathway for the cellular uptake of Aβ42 via apoE dependent and independent mechanisms This study suggests that the complex may potentially be a novel pharmacological target to decrease neuronal Aβ42 internalization and accumulation, which may represent a new strategy for inhibiting the rate of neurotoxicity, neurodegeneration, and progression of AD
University of California, San Francisco1, Case Western Reserve University2, University of Pennsylvania3, University of California, Los Angeles4, Mayo Clinic5, University of Washington6, Harvard University7, Indiana University – Purdue University Indianapolis8, University of North Carolina at Chapel Hill9, Johns Hopkins University10, University of Toronto11, Washington University in St. Louis12, Columbia University13, Northwestern University14, University of British Columbia15, University of Texas Southwestern Medical Center16, University of California, San Diego17, University of Alabama at Birmingham18
TL;DR: Familial frontotemporal lobar degeneration offers a unique opportunity to develop predictors of symptom onset in neurodegenerative diseases.
Abstract: Introduction Some models of therapy for neurodegenerative diseases envision starting treatment before symptoms develop. Demonstrating that such treatments are effective requires accurate knowledge of when symptoms would have started without treatment. Familial frontotemporal lobar degeneration offers a unique opportunity to develop predictors of symptom onset. Methods We created dementia risk scores in 268 familial frontotemporal lobar degeneration family members by entering covariate-adjusted standardized estimates of brain atrophy into a logistic regression to classify asymptomatic versus demented participants. The score's predictive value was tested in a separate group who were followed up longitudinally (stable vs. converted to dementia) using Cox proportional regressions with dementia risk score as the predictor. Results Cross-validated logistic regression achieved good separation of asymptomatic versus demented (accuracy = 90%, SE = 0.06). Atrophy scores predicted conversion from asymptomatic or mildly/questionably symptomatic to dementia (HR = 1.51, 95% CI: [1.16,1.98]). Discussion Individualized quantification of baseline brain atrophy is a promising predictor of progression in asymptomatic familial frontotemporal lobar degeneration mutation carriers.
TL;DR: A detailed biochemical and biophysical characterization of the tau-binding properties of gosuranemab, a humanized monoclonal antibody directed against N-terminal tau that is currently being investigated as a treatment for AD is reported.