Along-tract analysis of the white matter is more informative about brain ageing, compared to whole-tract analysis

AbstractMaternal brain adaptations occur in response to pregnancy, but little is known about how parity impacts white matter (WM) microstructure and WM ageing trajectories later in life. Utilising global and regional brain-age prediction based on multi-shell diffusion MRI data, we investigated the association between previous childbirths and WM brain age in 8,895 women in the UK Biobank cohort (age range = 54 - 81 years). The results showed that a higher number of previous childbirths was associated with lower WM brain age, in line with previous studies showing less evident grey matter (GM) brain ageing in parous relative to nulliparous women. Both global WM and GM brain age estimates showed unique contributions to the association with previous childbirths, suggesting partly independent processes. Corpus callosum contributed uniquely to the global WM association with previous childbirths, and showed a stronger relationship relative to several other tracts. While our findings demonstrate a link between reproductive history and brain WM characteristics later in life, longitudinal studies are required to understand how parity influences women’s WM trajectories across the lifespan.

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Inflammaging in Major Depressive Disorder: Associations between markers of inflammation and brain ageing in depression across two large community-based cohorts

10.1101/2021.12.17.21267979 ◽

2021 ◽

Author(s):

Claire Green ◽

Marco Squillace ◽

Anna J. Stevenson ◽

Aleks Stolicyn ◽

Mathew A. Harris ◽

...

Keyword(s):

Major Depressive Disorder ◽

White Matter ◽

Depressive Disorder ◽

Chronic Inflammation ◽

Interaction Effects ◽

Community Dwelling ◽

Community Based ◽

Major Depressive ◽

Brain Ageing

Background: Major Depressive Disorder (MDD) is associated with accelerated ageing trajectories including functional markers of ageing, cellular ageing and markers of poor brain health. The biological mechanisms underlying these associations remain poorly understood. Chronic inflammation is also associated with advanced ageing; however, the degree to which long-term inflammation plays a role in ageing in MDD remains unclear, partly due to difficulties differentiating long-term inflammation from acute cross-sectional measures. Methods: Here, we use a longer-term measure of inflammation: a DNA methylation-based marker of C-reactive protein (DNAm CRP), in a large cohort of individuals deeply phenotyped for MDD (Generation Scotland, GS, N=804). We investigate associations between DNAm CRP and serum CRP using linear modelling with two brain ageing neuroimaging-derived phenotypes: (i) a machine learning based measure of brain-predicted age difference (brain-PAD) and (ii) white matter hyperintensities (WMH). We then examine inflammation by depression interaction effects for these brain ageing phenotypes. We sought to replicate findings in an independent sample of older community-dwelling adults (Lothian Birth Cohort 1936, LBC1936; N=615). Results: DNAm CRP was significantly associated with increased brain-PAD (β=0.111, p=0.015), which was replicated in the independent sample with a similar significant effect size (β=0.114, p=0.012). There were no associations between the inflammation markers and WMH phenotypes in the GS-imaging sample, however in the LBC1936 sample, DNAm CRP was significantly associated with both Wahlund infratentorial (β=0.15, PFDR= 0.006) and Fazekas deep white matter hyperintensity scores (β= 0.116, PFDR=0.033). There were no interaction effects between inflammation and MDD in either cohort. Conclusions: This study found robust associations between a longer-term marker of inflammation and brain ageing as measured by brain-PAD, consistent across two large independent samples. However, we found no evidence for interaction effects between inflammation and MDD on any brain ageing phenotype in these community-based cohorts. These findings provide evidence that chronic inflammation is associated with increased brain ageing, which is not specific to MDD. Future work should investigate these relationships in clinical samples including with other inflammatory biomarkers and should furthermore aim to determine causal directionality.

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Building and hacking open source hardware

Research Ideas and Outcomes ◽

10.3897/rio.4.e31701 ◽

2018 ◽

Vol 4 ◽

Cited By ~ 1

Author(s):

Simone Monachino ◽

Eric James McDermott ◽

Andre Maia Chagas

Keyword(s):

Machine Learning ◽

Nervous System ◽

White Matter ◽

Functional Connectivity ◽

Brain Ageing ◽

3D Printed ◽

Do It Yourself ◽

White Matter Tractography ◽

Open Source Hardware

The first edition of the Aspects of Neuroscience Brainhack took place at the Department of Physics at University of Warsaw, Poland between November 17th and 19th 2017. This hackathon was one of the satellite events of the Aspects of Neuroscience conference, it was organized by the Brainhack organization to promote interaction between researchers, encouraging open (neuro)science and collaborations on projects related to the study of the nervous system. The event had a total of nine projects on many different topics including functional connectivity research, white matter tractography, classification of brain-ageing biomarkers through machine learning, presentation of a portable one channel EEG registration device and a do it yourself 3D-printed neurobiology lab. The latter is highlighted in this paper.

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Parental lifespan and polygenic risk score of longevity are associated with white matter hyperintensities

10.1101/2021.02.02.21251026 ◽

2021 ◽

Author(s):

Chao Dong ◽

Anbupalam Thalamuthu ◽

Jiyang Jiang ◽

Karen A. Mather ◽

Henry Brodaty ◽

...

Keyword(s):

White Matter ◽

Risk Score ◽

White Matter Hyperintensity ◽

Human Longevity ◽

Cerebral White Matter ◽

Polygenic Risk Score ◽

Replication Sample ◽

Polygenic Risk ◽

Discovery Sample ◽

Brain Ageing

AbstractHuman longevity is moderately heritable and is hence influenced by both genetic and environmental factors. However, there remains considerable uncertainty regarding its relationship with brain ageing. In this study, we investigated the associations of parental lifespan (parental age at death) and polygenic risk score for longevity (longevity-PRS) with structural magnetic resource imaging (MRI) brain metrics considered to reflect the brain ageing process. We used a discovery sample (N = 19136) from the UK Biobank and a replication sample (N =809) from the Sydney Memory and Ageing Study and the Older Australian Twins Study. We found lower cerebral white matter hyperintensity (WMH) volumes to be significantly associated with longer parental lifespan in the discovery and replication samples and higher longevity-PRS in the discovery sample and a similar trend in the replication sample. The association of longevity-PRS with WMH remained significant after removing the influence of the apolipoprotein E locus. Additionally, the effects of longevity-PRS on the association were more prominent in males, especially in the older-male group. Our findings suggest that human longevity-related genes may have an influence on WMH burden, suggesting WMH volume may be a biomarker for longevity and an ageing endophenotype.

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White matter hyperintensities and imaging patterns of brain ageing in the general population

Brain ◽

10.1093/brain/aww008 ◽

2016 ◽

Vol 139 (4) ◽

pp. 1164-1179 ◽

Cited By ~ 144

Author(s):

Mohamad Habes ◽

Guray Erus ◽

Jon B. Toledo ◽

Tianhao Zhang ◽

Nick Bryan ◽

...

Keyword(s):

White Matter ◽

General Population ◽

White Matter Hyperintensities ◽

Brain Ageing

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Review for "The distribution, number and certain neurochemical identities of infracortical white matter neurons in the brains of three megachiropteran bat species"

10.1002/cne.24894/v1/review2 ◽

2020 ◽

Keyword(s):

White Matter

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FT-IR microspectroscopic analysis of diseased white matter brain tissues

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100141214 ◽

1995 ◽

Vol 53 ◽

pp. 968-969

Author(s):

Steven M. Le Vine ◽

David L. Wetzel

Keyword(s):

White Matter ◽

Gray Matter ◽

Twitcher Mouse ◽

Grid Pattern ◽

Marked Contrast ◽

Spatially Resolved ◽

Ft Ir ◽

Ir Microspectroscopy ◽

Chemical Evidence

In situ FT-IR microspectroscopy has allowed spatially resolved interrogation of different parts of brain tissue. In previous work the spectrrscopic features of normal barin tissue were characterized. The white matter, gray matter and basal ganglia were mapped from appropriate peak area measurements from spectra obtained in a grid pattern. Bands prevalent in white matter were mostly associated with the lipid. These included 2927 and 1469 cm-1 due to CH2 as well as carbonyl at 1740 cm-1. Also 1235 and 1085 cm-1 due to phospholipid and galactocerebroside, respectively (Figs 1and2). Localized chemical changes in the white matter as a result of white matter diseases have been studied. This involved the documentation of localized chemical evidence of demyelination in shiverer mice in which the spectra of white matter lacked the marked contrast between it and gray matter exhibited in the white matter of normal mice (Fig. 3).The twitcher mouse, a model of Krabbe’s desease, was also studied. The purpose in this case was to look for a localized build-up of psychosine in the white matter caused by deficiencies in the enzyme responsible for its breakdown under normal conditions.

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