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van den Born, B.-J. H.

Publications and source records attributed to van den Born, B.-J. H..

5 recordsLinked to original sources

Ethnic differences in gut microbiota composition and functional capacity persist over six years in the HELIUS multi-ethnic longitudinal cohort

Background: Ethnic minority groups in Western Europe carry a disproportionate cardiometabolic disease burden not fully explained by conventional risk factors, and their gut microbiomes differ markedly from those of European-origin populations. Whether these differences persist over time has not been examined prospectively. Results: We followed 1,903 participants from six ethnic groups in the HELIUS cohort over 6 years, using faecal 16S rRNA sequencing across all groups and shotgun metagenomics in a matched Dutch and South-Asian Surinamese subset (N = 238 per group). The extent of microbiota compositional change over time differed between ethnic groups: Moroccan participants showed the largest change, while the Dutch and South-Asian Surinamese participants were most stable. Diabetes mellitus and medication use at baseline were associated with greater compositional drift. However, ethnic differences in composition were largely preserved across all six groups (16S: ethnicity R2 0.044 to 0.037; all 15 pairwise contrasts significant at follow-up) and in the shotgun subset (R2 0.047 to 0.037). At the species level, 61 of 78 ethnicity-associated species remained differentially abundant at follow-up. Alistipes putredinis, the species converging most strongly, was absent at baseline in 43% of South-Asian Surinamese participants, and the convergence was consistent with acquisition of this species by this group. At strain level, within-person strain sharing declined with follow-up duration but was similar between ethnic groups. Within hosts, 90% of A. putredinis populations were retained as the same or a closely related lineage, and within the retained subset, microdiversity increased in both groups. Ethnic differences in functional profiles persisted to a similar extent as those in composition, with limited convergence in fibre-degrading enzyme families (GH5_37, GH26). The total antibiotic resistance gene (ARG) burden in the gut microbiome declined similarly in both groups over time. Dutch participants showed higher baseline ARG diversity that converged toward South-Asian Surinamese levels, while class-level differences were predominantly stable. Conclusions: Six years of follow-up in a shared urban environment narrowed ethnic differences in the gut microbiome only modestly; assuming exponential decline, the observed change corresponds to a half-life of roughly two decades.

microbiology↗

Multi-cohort, multi-sequence harmonisation for cerebrovascular brain age

IntroductionHigher brain-predicted age gaps (BAG), based on anatomical brain scans, have been associated with cognitive decline among elderly participants. Adding a cerebrovascular component, in the form of arterial spin labelling (ASL) perfusion MRI, can improve the BAG predictions and potentially increase sensitivity to cardiovascular health, a contributor to brain ageing and cognitive decline. ASL acquisition differences are likely to influence brain age estimations, and data harmonisation becomes indispensable for multi-cohort brain age studies including ASL. In this multi-cohort, multi-sequence study, we investigate harmonisation methods to improve the generalisability of cerebrovascular brain age. MethodsA multi-study dataset of 2608 participants was used, comprising structural T1-weighted (T1w), FLAIR, and ASL 3T MRI data. The single scanner training dataset consisted of 806 healthy participants, age 50{+/-}17, 18-95 years. The testing datasets comprised four cohorts (n=1802, age 67{+/-}8, 37-90 years). Image features included grey and white matter (GM/WM) volumes (T1w), WM hyperintensity volumes and counts (FLAIR), and ASL cerebral blood flow (CBF) and its spatial coefficient of variation (sCoV). Feature harmonisation was performed using NeuroComBat, CovBat, NeuroHarmonize, OPNested ComBat, AutoComBat, and RELIEF. ASL-only and T1w+FLAIR+ASL brain age models were trained using ExtraTrees. Model performance was assessed through the mean absolute error (MAE) and mean BAG. ResultsASL feature differences between cohorts decreased after harmonisation for all methods (p<0.05), mostly for RELIEF. Negative associations between age and GM CBF (b=-0.37, R2=0.13, unharmonised) increased after harmonisation for all methods (b<-0.42, R2>0.12) but weakened for RELIEF (b=-0.28, R2=0.14). In the ASL-only model, MAE improved for all harmonisation methods from 11.1{+/-}7.5 years to less than 8.8{+/-}6.2 years (p<0.001), while BAGs changed from 0.6{+/-}13.4 years to less than -1.03{+/-}7.92 years (p<0.001). For T1w+FLAIR+ASL, MAE (5.9{+/-}4.6 years, unharmonised) increased for all harmonisation methods non-significantly to above 6.0{+/-}4.9 years (p>0.42) and significantly for RELIEF (6.4{+/-}5.2 years, p=0.02), while BAGs non-significantly differed from -1.6{+/-}7.3 years to between -1.3{+/-}4.7 and -2.0{+/-}8.0 years (p>0.82). In general, the ASL-specific parameter harmonisation method AutoComBat performed nominally best. DiscussionHarmonisation of ASL features improves feature consistency between studies and also improves brain age estimations when only ASL features are used. ASL-specific parameter harmonisation methods perform nominally better than basic mean and scale adjustment or latent-factor approaches, suggesting that ASL acquisition parameters should be considered when harmonising ASL data. Although multi-modal brain age estimations were improved less by ASL-only harmonisation, possibly due to weaker associations between age and ASL features compared to T1w features feature importance, studies investigating pathological ASL-feature distributions might still benefit from harmonisation. These findings advocate for ASL-parameter specific harmonisation to explore associations between cardiovascular risk factors, brain ageing, and cognitive decline using multi-cohort ASL and cerebrovascular brain age studies.

neuroscience↗

Phylogeny and disease links of a widespread and ancient gut phage lineage

Viruses are a core component of the human microbiome, impacting health and disease through interactions with gut bacteria1 and the immune system2. Most viruses in the human microbiome are bacteriophages, which exclusively infect bacteria. Individual gut bacteriophages can affect bacterial bile acid deconjugation3, and can alter their infection strategy based on dietary content4. Up to recently, most studies of the gut virome have focused on low taxonomic scales (e.g., viral operational taxonomic units), hampering population-level analyses. We previously identified the expansive and widespread Candidatus Heliusviridae bacteriophage family in a cohort with inhabitants of Amsterdam, the Netherlands. Here, we study their biodiversity and evolution in a wide variety of human populations. With a detailed phylogeny based on sequences from six viral genome databases, we now propose the Candidatus order Heliusvirales to accommodate these viruses. We identify Ca. Heliusvirales viruses in 80% of 5,441 individuals across 39 studies, and also in nine out of thirteen analyzed metagenomes from ancient humans that lived in Europe and North America between 1,000 and 5,000 years ago. We show that a large Ca. Heliusvirales lineage has diversified starting at the appearance of Homo sapiens some 200,000-300,000 years ago. Ancient peoples and modern hunter-gatherers further have distinct Ca. Heliusvirales populations that are characterized by lower richness than modern urbanized people. Within urbanized people, those suffering from type 1 and type 2 diabetes, as well as inflammatory bowel disease, have higher Ca. Heliusvirales richness than healthy controls. We thus conclude that these ancient core members of the human gut virome have thrived with increasingly westernized lifestyles of the human population.

microbiology↗

Gut-derived bacterial flagellin induces beta-cell inflammation and dysfunction

ObjectiveHyperglycemia and type 2 diabetes (T2D) are caused by failure of pancreatic beta cells. The role of the gut microbiota in T2D has been studied but causal links remain enigmatic. DesignObese individuals with or without T2D were included from two independent Dutch cohorts. Human data was translated in vitro and in vivo by using pancreatic islets from C57BL6/J mice and by injecting flagellin into obese mice. ResultsFlagellin is part of the bacterial locomotor appendage flagellum, present on gut bacteria including Enterobacteriaceae, which we show to be more abundant in the gut of individuals with T2D. Subsequently, flagellin induces a pro-inflammatory response in pancreatic islets mediated by the Toll-like receptor (TLR)-5 expressed on resident islet macrophages. This inflammatory response associated with beta-cell dysfunction, characterized by reduced insulin gene expression, impaired proinsulin processing and stress-induced insulin hypersecretion in vitro and in vivo in mice. ConclusionWe postulate that increased systemically disseminated flagellin in T2D is a contributing factor to beta cell failure in time and represents a novel therapeutic target. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=136 SRC="FIGDIR/small/463317v1_ufig1.gif" ALT="Figure 1"> View larger version (38K): org.highwire.dtl.DTLVardef@b719aeorg.highwire.dtl.DTLVardef@f72958org.highwire.dtl.DTLVardef@bb7af5org.highwire.dtl.DTLVardef@859c70_HPS_FORMAT_FIGEXP M_FIG C_FIG

molecular biology↗

Members of a highly widespread bacteriophage family are hallmarks of metabolic syndrome gut microbiomes

There is significant interest in altering the course of cardiometabolic disease development via the gut microbiome. Nevertheless, the highly abundant phage members -which impact gut bacteria- of the complex gut ecosystem remain understudied. Here, we characterized gut phageome changes associated with metabolic syndrome (MetS), a highly prevalent clinical condition preceding cardiometabolic disease. MetS gut phageome populations exhibited decreased richness and diversity, but larger inter-individual variation. These populations were enriched in phages infecting Bacteroidaceae and depleted in those infecting Ruminococcaeae. Differential abundance analysis identified eighteen viral clusters (VCs) as significantly associated with either MetS or healthy phageomes. Among these are a MetS-associated Roseburia VC that is related to healthy control-associated Faecalibacterium and Oscillibacter VCs. Further analysis of these VCs revealed the Candidatus Heliusviridae, a highly widespread gut phage lineage found in 90+% of the participants. The identification of the temperate Ca. Heliusviridae provides a novel starting point to a better understanding of the effect that phages have on their bacterial hosts and the role that this plays in MetS.

microbiology↗