Browsing by Author "Frasier, Mark"

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    A proteogenomic view of Parkinson's disease causality and heterogeneity
    (Springer Nature, 2023-02-11) Kaiser, Sergio; Zhang, Luqing; Mollenhauer, Brit; Jacob, Jaison; Longerich, Simonne; Del-Aguila, Jorge; Marcus, Jacob; Raghavan, Neha; Stone, David; Fagboyegun, Olumide; Galasko, Douglas; Dakna, Mohammed; Bilican, Bilada; Dovlatyan, Mary; Kostikova, Anna; Li, Jingyao; Peterson, Brant; Rotte, Michael; Sanz, Vinicius; Foroud, Tatiana; Hutten, Samantha J.; Frasier, Mark; Iwaki, Hirotaka; Singleton, Andrew; Marek, Ken; Crawford, Karen; Elwood, Fiona; Messa, Mirko; Serrano-Fernandez, Pablo; Medical and Molecular Genetics, School of Medicine
    The pathogenesis and clinical heterogeneity of Parkinson’s disease (PD) have been evaluated from molecular, pathophysiological, and clinical perspectives. High-throughput proteomic analysis of cerebrospinal fluid (CSF) opened new opportunities for scrutinizing this heterogeneity. To date, this is the most comprehensive CSF-based proteomics profiling study in PD with 569 patients (350 idiopathic patients, 65 GBA + mutation carriers and 154 LRRK2 + mutation carriers), 534 controls, and 4135 proteins analyzed. Combining CSF aptamer-based proteomics with genetics we determined protein quantitative trait loci (pQTLs). Analyses of pQTLs together with summary statistics from the largest PD genome wide association study (GWAS) identified 68 potential causal proteins by Mendelian randomization. The top causal protein, GPNMB, was previously reported to be upregulated in the substantia nigra of PD patients. We also compared the CSF proteomes of patients and controls. Proteome differences between GBA + patients and unaffected GBA + controls suggest degeneration of dopaminergic neurons, altered dopamine metabolism and increased brain inflammation. In the LRRK2 + subcohort we found dysregulated lysosomal degradation, altered alpha-synuclein processing, and neurotransmission. Proteome differences between idiopathic patients and controls suggest increased neuroinflammation, mitochondrial dysfunction/oxidative stress, altered iron metabolism and potential neuroprotection mediated by vasoactive substances. Finally, we used proteomic data to stratify idiopathic patients into “endotypes”. The identified endotypes show differences in cognitive and motor disease progression based on previously reported protein-based risk scores.Our findings not only contribute to the identification of new therapeutic targets but also to shape personalized medicine in CNS neurodegeneration.
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    Assessment of heterogeneity among participants in the Parkinson's Progression Markers Initiative cohort using α-synuclein seed amplification: a cross-sectional study
    (Elsevier, 2023) Siderowf, Andrew; Concha-Marambio, Luis; Lafontant, David-Erick; Farris, Carly M.; Ma, Yihua; Urenia, Paula A.; Nguyen, Hieu; Alcalay, Roy N.; Chahine, Lana M.; Foroud, Tatiana; Galasko, Douglas; Kieburtz, Karl; Merchant, Kalpana; Mollenhauer, Brit; Poston, Kathleen L.; Seibyl, John; Simuni, Tanya; Tanner, Caroline M.; Weintraub, Daniel; Videnovic, Aleksandar; Choi, Seung Ho; Kurth, Ryan; Caspell-Garcia, Chelsea; Coffey, Christopher S.; Frasier, Mark; Oliveira, Luis M. A.; Hutten, Samantha J.; Sherer, Todd; Marek, Kenneth; Soto, Claudio; Parkinson's Progression Markers Initiative; Medical and Molecular Genetics, School of Medicine
    Background: Emerging evidence shows that α-synuclein seed amplification assays (SAAs) have the potential to differentiate people with Parkinson's disease from healthy controls. We used the well characterised, multicentre Parkinson's Progression Markers Initiative (PPMI) cohort to further assess the diagnostic performance of the α-synuclein SAA and to examine whether the assay identifies heterogeneity among patients and enables the early identification of at-risk groups. Methods: This cross-sectional analysis is based on assessments done at enrolment for PPMI participants (including people with sporadic Parkinson's disease from LRRK2 and GBA variants, healthy controls, prodromal individuals with either rapid eye movement sleep behaviour disorder (RBD) or hyposmia, and non-manifesting carriers of LRRK2 and GBA variants) from 33 participating academic neurology outpatient practices worldwide (in Austria, Canada, France, Germany, Greece, Israel, Italy, the Netherlands, Norway, Spain, the UK, and the USA). α-synuclein SAA analysis of CSF was performed using previously described methods. We assessed the sensitivity and specificity of the α-synuclein SAA in participants with Parkinson's disease and healthy controls, including subgroups based on genetic and clinical features. We established the frequency of positive α-synuclein SAA results in prodromal participants (RBD and hyposmia) and non-manifesting carriers of genetic variants associated with Parkinson's disease, and compared α-synuclein SAA to clinical measures and other biomarkers. We used odds ratio estimates with 95% CIs to measure the association between α-synuclein SAA status and categorical measures, and two-sample 95% CIs from the resampling method to assess differences in medians between α-synuclein SAA positive and negative participants for continuous measures. A linear regression model was used to control for potential confounders such as age and sex. Findings: This analysis included 1123 participants who were enrolled between July 7, 2010, and July 4, 2019. Of these, 545 had Parkinson's disease, 163 were healthy controls, 54 were participants with scans without evidence of dopaminergic deficit, 51 were prodromal participants, and 310 were non-manifesting carriers. Sensitivity for Parkinson's disease was 87·7% (95% CI 84·9-90·5), and specificity for healthy controls was 96·3% (93·4-99·2). The sensitivity of the α-synuclein SAA in sporadic Parkinson's disease with the typical olfactory deficit was 98·6% (96·4-99·4). The proportion of positive α-synuclein SAA was lower than this figure in subgroups including LRRK2 Parkinson's disease (67·5% [59·2-75·8]) and participants with sporadic Parkinson's disease without olfactory deficit (78·3% [69·8-86·7]). Participants with LRRK2 variant and normal olfaction had an even lower α-synuclein SAA positivity rate (34·7% [21·4-48·0]). Among prodromal and at-risk groups, 44 (86%) of 51 of participants with RBD or hyposmia had positive α-synuclein SAA (16 of 18 with hyposmia, and 28 of 33 with RBD). 25 (8%) of 310 non-manifesting carriers (14 of 159 [9%] LRRK2 and 11 of 151 [7%] GBA) were positive. Interpretation: This study represents the largest analysis so far of the α-synuclein SAA for the biochemical diagnosis of Parkinson's disease. Our results show that the assay classifies people with Parkinson's disease with high sensitivity and specificity, provides information about molecular heterogeneity, and detects prodromal individuals before diagnosis. These findings suggest a crucial role for the α-synuclein SAA in therapeutic development, both to identify pathologically defined subgroups of people with Parkinson's disease and to establish biomarker-defined at-risk cohorts.
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    Differences in the Presentation and Progression of Parkinson's Disease by Sex
    (Wiley, 2021) Iwaki, Hirotaka; Blauwendraat, Cornelis; Leonard, Hampton L.; Makarious, Mary B.; Kim, Jonggeol J.; Liu, Ganqiang; Maple-Grødem, Jodie; Corvol, Jean-Christophe; Pihlstrøm, Lasse; van Nimwegen, Marlies; Smolensky, Luba; Amondikar, Ninad; Hutten, Samantha J.; Frasier, Mark; Nguyen, Khanh-Dung H.; Rick, Jacqueline; Eberly, Shirley; Faghri, Faraz; Auinger, Peggy; Scott, Kirsten M.; Wijeyekoon, Ruwani; Van Deerlin, Vivianna M.; Hernandez, Dena G.; Gibbs, Raphael J.; Day-Williams, Aaron G.; Brice, Alexis; Alves, Guido; Noyce, Alastair J.; Tysnes, Ole-Bjørn; Evans, Jonathan R.; Breen, David P.; Estrada, Karol; Wegel, Claire E.; Danjou, Fabrice; Simon, David K.; Andreassen, Ole A.; Ravina, Bernard; Toft, Mathias; Heutink, Peter; Bloem, Bastiaan R.; Weintraub, Daniel; Barker, Roger A.; Williams-Gray, Caroline H.; van de Warrenburg, Bart P.; Van Hilten, Jacobus J.; Scherzer, Clemens R.; Singleton, Andrew B.; Nalls, Mike A.; Medical and Molecular Genetics, School of Medicine
    Background: Previous studies reported various symptoms of Parkinson's disease (PD) associated with sex. Some were conflicting or confirmed in only one study. Objectives: We examined sex associations to PD phenotypes cross-sectionally and longitudinally in large-scale data. Methods: We tested 40 clinical phenotypes, using longitudinal, clinic-based patient cohorts, consisting of 5946 patients, with a median follow-up of 3.1 years. For continuous outcomes, we used linear regressions at baseline to test sex-associated differences in presentation, and linear mixed-effects models to test sex-associated differences in progression. For binomial outcomes, we used logistic regression models at baseline and Cox regression models for survival analyses. We adjusted for age, disease duration, and medication use. In the secondary analyses, data from 17 719 PD patients and 7588 non-PD participants from an online-only, self-assessment PD cohort were cross-sectionally evaluated to determine whether the sex-associated differences identified in the primary analyses were consistent and unique to PD. Results: Female PD patients had a higher risk of developing dyskinesia early during the follow-up period, with a slower progression in activities of daily living difficulties, and a lower risk of developing cognitive impairments compared with male patients. The findings in the longitudinal, clinic-based cohorts were mostly consistent with the results of the online-only cohort. Conclusions: We observed sex-associated contributions to PD heterogeneity. These results highlight the necessity of future research to determine the underlying mechanisms and importance of personalized clinical management.
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    Finding useful biomarkers for Parkinson's disease
    (American Association for the Advancement of Science, 2018-08-15) Chen-Plotkin, Alice S.; Albin, Roger; Alcalay, Roy; Babcock, Debra; Bajaj, Vikram; Bowman, Dubois; Buko, Alex; Cedarbaum, Jesse; Chelsky, Daniel; Cookson, Mark; Dawson, Ted; Dewey, Richard; Foroud, Tatiana; Frasier, Mark; German, Dwight; Gwinn, Katrina; Huang, Xuemei; Kopil, Catherine; Kremer, Thomas; Lasch, Shirley; Marek, Ken; Marto, Jarrod; Merchant, Kalpana; Mollenhauer, Brit; Naito, Anna; Potashkin, Judith; Reimer, Alyssa; Rosenthal, Liana; Saunders-Pullman, Rachel; Scherzer, Clemens R.; Sherer, Todd; Singleton, Andrew; Sutherland, Margaret; Thiele, Ines; van der Brug, Marcel; Van Keuren-Jensen, Kendall; Vaillancourt, David; Walt, David; West, Andrew; Zhang, Jing; Medical and Molecular Genetics, School of Medicine
    Parkinson’s Disease affects more than 4 million people worldwide, and biomarkers to bolster the therapeutic development pipeline are urgently needed. The recent advent of an “ecosystem” of shared biosample biorepositories and data enables us to consider how to focus PD biomarker activity to best translate efforts into real-world impact.
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    Validation of Serum Neurofilament Light Chain as a Biomarker of Parkinson’s Disease Progression
    (Wiley, 2020-11) Mollenhauer, Brit; Dakna, Mohammed; Kruse, Niels; Galasko, Douglas; Foroud, Tatiana; Zetterberg, Henrik; Schade, Sebastian; Gera, Roland G.; Wang, Wenting; Gao, Feng; Frasier, Mark; Chahine, Lana M.; Coffey, Christopher S.; Singleton, Andrew B.; Simuni, Tanya; Weintraub, Daniel; Seibyl, John; Toga, Arthur W.; Tanner, Caroline M.; Kieburtz, Karl; Marek, Kenneth; Siderowf, Andrew; Cedarbaum, Jesse M.; Hutten, Samantha J.; Trenkwalder, Claudia; Graham, Danielle; Medical and Molecular Genetics, School of Medicine
    Background: The objective of this study was to assess neurofilament light chain as a Parkinson's disease biomarker. Methods: We quantified neurofilament light chain in 2 independent cohorts: (1) longitudinal cerebrospinal fluid samples from the longitudinal de novo Parkinson's disease cohort and (2) a large longitudinal cohort with serum samples from Parkinson's disease, other cognate/neurodegenerative disorders, healthy controls, prodromal conditions, and mutation carriers. Results: In the Parkinson's Progression Marker Initiative cohort, mean baseline serum neurofilament light chain was higher in Parkinson's disease patients (13 ± 7.2 pg/mL) than in controls (12 ± 6.7 pg/mL), P = 0.0336. Serum neurofilament light chain increased longitudinally in Parkinson's disease patients versus controls (P < 0.01). Motor scores were positively associated with neurofilament light chain, whereas some cognitive scores showed a negative association. Conclusions: Neurofilament light chain in serum samples is increased in Parkinson's disease patients versus healthy controls, increases over time and with age, and correlates with clinical measures of Parkinson's disease severity. Although the specificity of neurofilament light chain for Parkinson's disease is low, it is the first blood-based biomarker candidate that could support disease stratification of Parkinson's disease versus other cognate/neurodegenerative disorders, track clinical progression, and possibly assess responsiveness to neuroprotective treatments. However, use of neurofilament light chain as a biomarker of response to neuroprotective interventions remains to be assessed.