| 1. |
- Bergström, Sofia, et al.
(författare)
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A panel of CSF proteins separates genetic frontotemporal dementia from presymptomatic mutation carriers : a GENFI study
- 2021
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Ingår i: Molecular Neurodegeneration. - : Springer Nature. - 1750-1326. ; 16:1
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Tidskriftsartikel (refereegranskat)abstract
- Background A detailed understanding of the pathological processes involved in genetic frontotemporal dementia is critical in order to provide the patients with an optimal future treatment. Protein levels in CSF have the potential to reflect different pathophysiological processes in the brain. We aimed to identify and evaluate panels of CSF proteins with potential to separate symptomatic individuals from individuals without clinical symptoms (unaffected), as well as presymptomatic individuals from mutation non-carriers. Methods A multiplexed antibody-based suspension bead array was used to analyse levels of 111 proteins in CSF samples from 221 individuals from families with genetic frontotemporal dementia. The data was explored using LASSO and Random forest. Results When comparing affected individuals with unaffected individuals, 14 proteins were identified as potentially important for the separation. Among these, four were identified as most important, namely neurofilament medium polypeptide (NEFM), neuronal pentraxin 2 (NPTX2), neurosecretory protein VGF (VGF) and aquaporin 4 (AQP4). The combined profile of these four proteins successfully separated the two groups, with higher levels of NEFM and AQP4 and lower levels of NPTX2 in affected compared to unaffected individuals. VGF contributed to the models, but the levels were not significantly lower in affected individuals. Next, when comparing presymptomatic GRN and C9orf72 mutation carriers in proximity to symptom onset with mutation non-carriers, six proteins were identified with a potential to contribute to a separation, including progranulin (GRN). Conclusion In conclusion, we have identified several proteins with the combined potential to separate affected individuals from unaffected individuals, as well as proteins with potential to contribute to the separation between presymptomatic individuals and mutation non-carriers. Further studies are needed to continue the investigation of these proteins and their potential association to the pathophysiological mechanisms in genetic FTD.
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| 2. |
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| 3. |
- Natarajan, Karthick, et al.
(författare)
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Plasma metabolomics of presymptomatic PSEN1-H163Y mutation carriers: a pilot study.
- 2021
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Ingår i: Annals of clinical and translational neurology. - : Wiley. - 2328-9503. ; 8:3, s. 579-591
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Tidskriftsartikel (refereegranskat)abstract
- PSEN1-H163Y carriers, at the presymptomatic stage, have reduced 18 FDG-PET binding in the cerebrum of the brain (Scholl et al., Neurobiol Aging 32:1388-1399, 2011). This could imply dysfunctional energy metabolism in the brain. In this study, plasma of presymptomatic PSEN1 mutation carriers was analyzed to understand associated metabolic changes.We analyzed plasma from noncarriers (NC, n=8) and presymptomatic PSEN1-H163Y mutation carriers (MC, n=6) via untargeted metabolomics using gas and liquid chromatography coupled with mass spectrometry, which identified 1199 metabolites. All the metabolites were compared between MC and NC using univariate analysis, as well as correlated with the ratio of Aβ1-42/Aβ1-40 , using Spearman's correlation. Altered metabolites were subjected to Ingenuity Pathway Analysis (IPA).Based on principal component analysis the plasma metabolite profiles were divided into dataset A and dataset B. In dataset A, when comparing between presymptomatic MC and NC, the levels of 79 different metabolites were altered. Out of 79, only 14 were annotated metabolites. In dataset B, 37 metabolites were significantly altered between presymptomatic MC and NC and nine metabolites were annotated. In both datasets, annotated metabolites represent amino acids, fatty acyls, bile acids, hexoses, purine nucleosides, carboxylic acids, and glycerophosphatidylcholine species. 1-docosapentaenoyl-GPC was positively correlated, uric acid and glucose were negatively correlated with the ratio of plasma Aβ1-42 /Aβ1-40 (P<0.05).This study finds dysregulated metabolite classes, which are changed before the disease symptom onset. Also, it provides an opportunity to compare with sporadic Alzheimer's Disease. Observed findings in this study need to be validated in a larger and independent Familial Alzheimer's Disease (FAD) cohort.
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| 4. |
- Remnestål, Julia, et al.
(författare)
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Altered levels of CSF proteins in patients with FTD, presymptomatic mutation carriers and non-carriers
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Ingår i: Translational Neurodegeneration. - 2047-9158.
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Tidskriftsartikel (refereegranskat)abstract
- Background. The clinical presentations of frontotemporal dementia (FTD) are diverse and overlap with other neurological disorders. There are, as of today, no biomarkers in clinical practice for diagnosing the disorders. Here, we aimed to find protein markers in cerebrospinal fluid (CSF) from patients with FTD, presymptomatic mutation carriers and non-carriers.Methods. Antibody suspension bead arrays were used to analyse 328 proteins in CSF from patients with behavioural variant FTD (bvFTD, n=16) and progressive primary aphasia (PPA, n=13), as well as presymptomatic mutation carriers (PMC, n=16) and non-carriers (NC, n=8). A total of 492 antibodies were used to measure protein levels by direct labelling of the CSF samples. The findings were further examined in an independent cohort including 13 FTD patients, 79 patients with Alzheimer’s disease and 18 healthy controls.Results. We found significantly altered protein levels in CSF from FTD patients compared to unaffected individuals (PMC and NC) for 26 proteins. The analysis show patterns of separation between unaffected individuals and FTD patients, especially for those with a clinical diagnosis of bvFTD. The most statistically significant differences in protein levels were found for VGF, TN-R, NPTXR, TMEM132D, PDYN and NF-M. Patients with FTD were found to have higher levels of TN-R and NF-M, and lower levels of VGF, NPTXR, TMEM132D and PDYN, compared to unaffected individuals. The main findings were reproduced in the independent cohort.Conclusion. In this pilot study, we show a separation of FTD patients from unaffected individuals based on protein levels in CSF. Further investigation is required to explore the CSF profiles in larger cohorts, but the results presented here has the potential to enable future clinical utilization of these potential biomarkers within FTD.
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| 5. |
- Remnestål, Julia, et al.
(författare)
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Altered levels of CSF proteins in patients with FTD, presymptomatic mutation carriers and non-carriers
- 2020
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Ingår i: Translational Neurodegeneration. - : Springer Nature. - 2047-9158. ; 9:1
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Tidskriftsartikel (refereegranskat)abstract
- Background: The clinical presentations of frontotemporal dementia (FTD) are diverse and overlap with other neurological disorders. There are, as of today, no biomarkers in clinical practice for diagnosing the disorders. Here, we aimed to find protein markers in cerebrospinal fluid (CSF) from patients with FTD, presymptomatic mutation carriers and non-carriers. Methods: Antibody suspension bead arrays were used to analyse 328 proteins in CSF from patients with behavioural variant FTD (bvFTD, n = 16) and progressive primary aphasia (PPA, n = 13), as well as presymptomatic mutation carriers (PMC, n = 16) and non-carriers (NC, n = 8). A total of 492 antibodies were used to measure protein levels by direct labelling of the CSF samples. The findings were further examined in an independent cohort including 13 FTD patients, 79 patients with Alzheimer's disease and 18 healthy controls. Results: We found significantly altered protein levels in CSF from FTD patients compared to unaffected individuals (PMC and NC) for 26 proteins. The analysis show patterns of separation between unaffected individuals and FTD patients, especially for those with a clinical diagnosis of bvFTD. The most statistically significant differences in protein levels were found for VGF, TN-R, NPTXR, TMEM132D, PDYN and NF-M. Patients with FTD were found to have higher levels of TN-R and NF-M, and lower levels of VGF, NPTXR, TMEM132D and PDYN, compared to unaffected individuals. The main findings were reproduced in the independent cohort. Conclusion: In this pilot study, we show a separation of FTD patients from unaffected individuals based on protein levels in CSF. Further investigation is required to explore the CSF profiles in larger cohorts, but the results presented here has the potential to enable future clinical utilization of these potential biomarkers within FTD.
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| 6. |
- Ullgren, Abbe
(författare)
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Protein and MRI profiling of genetic frontotemporal dementia
- 2024
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Frontotemporal dementia (FTD) is a group of neurodegenerative diseases with a wide range of symptoms such as loss of inhibition and social cognition, language impairment and motor dysfunction. Genetic FTD, characterized by mutations in one of several disease-causing genes, accounts for 10 - 30% of all cases of FTD. The most common causes for genetic FTD are repeat expansions in C9orf72 and mutations in GRN or MAPT, but there are also many other, rarer causes. Each mutation gives rise to a specific subtype of genetic FTD. These subtypes differ not only in clinical presentation, but also in the underlying pathophysiology. To be able to study, and eventually treat, genetic FTD a thorough understanding of the genetic subtypes is crucial. In this thesis we characterized the effects of a p.Ala417* mutation in TBK1, showing that it causes haploinsufficiency as well as demonstrating systemic effects on the K63 ubiquitination system. We also analyzed blood and cerebrospinal fluid samples from carriers of pathogenic mutations associated with genetic FTD to find biomarkers that can distinguish symptomatic mutation carriers from healthy controls or distinguish between the different genetic subtypes. We also studied how these biomarker candidates correlate with cortical and subcortical atrophy in genetic FTD. The results of these studies have provided a further understanding of genetic FTD as well as new biomarker candidates for several pathological processes.
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