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de Groot, E.

Publications and source records attributed to de Groot, E..

3 recordsLinked to original sources

Beige fat appearance during lipoatrophy reveals trade-offs between metabolic homeostasis and female fertility

White adipose tissue (WAT) meets the energetic demands required for estrous cycle regularity, ovulation, and reproductive success in women. Here, we report WAT loss and subsequent female-specific compensatory beige fat recruitment impact metabolic and reproductive outcomes in mice. Female mice that undergo progressive lipoatrophy ( fat-less) displayed disrupted estrous cycles, reduced ovarian reserve, and subfertility. These effects were attributable to an accumulation of thermogenic beige fat cells in residual subcutaneous WAT depots and greater energy expenditure. Conversely, high-fat diet lowered energy expenditure and rescued estrous cycle regularity among fat-less mice compared to littermate controls, despite profound insulin resistance and metabolic dysfunction. Together, these findings provide evidence of trade-offs between the maintenance of metabolic homeostasis and reproduction, where increased energy expenditure and beige fat cell emergence compensate for fat loss but occur at the expense of fecundity in female mice.

cell biology↗

Predictive coding is a consequence of energy efficiency in recurrent neural networks

Predictive coding represents a promising framework for understanding brain function. It postulates that the brain continuously inhibits predictable sensory input, ensuring a preferential processing of surprising elements. A central aspect of this view is its hierarchical connectivity, involving recurrent message passing between excitatory bottom-up signals and inhibitory top-down feedback. Here we use computational modelling to demonstrate that such architectural hard-wiring is not necessary. Rather, predictive coding is shown to emerge as a consequence of energy efficiency. When training recurrent neural networks to minimise their energy consumption while operating in predictive environments, the networks self-organise into prediction and error units with appropriate inhibitory and excitatory interconnections, and learn to inhibit predictable sensory input. Moving beyond the view of purely top-down driven predictions, we furthermore demonstrate, via virtual lesioning experiments, that networks perform predictions on two timescales: fast lateral predictions among sensory units, and slower prediction cycles that integrate evidence over time.

neuroscience↗

Variability of core microbiota in newly diagnosed treatment-naïve paediatric Inflammatory Bowel Disease patients

BACKGROUND & AIMSIntestinal microbiota is considered to play a crucial role in the aetiology of inflammatory bowel disease (IBD). We aimed to describe faecal microbiota composition and dynamics in a large cohort of children with de novo (naive) IBD, in comparison to healthy paediatric controls (HC).\n\nMETHODSIn this prospective study, performed at two tertiary centres, faecal samples from newly diagnosed, treatment-naive paediatric IBD patients were collected prior to bowel cleansing for colonoscopy (t0) and 1, 3 and 6 weeks and 3 months after initiation of therapy. The microbial profiles of Crohns disease (CD) and Ulcerative colitis (UC) patients were compared with HC and linked to therapeutic response. Microbiota composition was analysed by IS-pro technology.\n\nRESULTSMicrobial profiles of 104 new IBD-patients (63 CD, 41 UC, median age 14.0 years) were compared to 61 HC (median 7.8 years). IBD was mainly characterised by decreased abundance of Alistipes finegoldi and Alistipes putredinis, which characterize a healthy state microbial core. The classifier including these core species as predictors achieved an AUC of the ROC curve of .87. Core bacteria tended to regain abundance during treatment, but did not reach healthy levels.\n\nCONCLUSIONFaecal microbiota profiles of children with de novo CD and UC can be discriminated from HC with high accuracy, mainly driven by a decreased abundance of species shaping the microbial core in the healthy state. Paediatric IBD can therefore be characterized by decreased abundance of certain bacterial species reflecting the healthy state rather than by the introduction of pathogens.

microbiology↗