NEWS
Stay updated about our progress
A new milestone in our traumatic brain injury research.
8 years ago already, we started working on TBI using animal models. In our first milestone paper we focused on the primary injury on the cerebral cortex and how inhibiting neuroinflamation could counteract its effects.
Now we have achieved a new milestone in our project, focusing on the effect of the secondary injury on the hippocampus, specially studying the effect of TBI on neural stem cell fate and the cellular composition of the dentate gyrus. In our recent paper in Nat. Comms we show how TBI promotes neurogenesis at the cost of astrogliogenesis in the adult hippocampus of male mice.
Our work is freely available here:
https://www.nature.com/articles/s41467-024-49299-6
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The 'middle-aging' brain
Middle age (roughly the fifth and sixth decades of human life) has historically been understudied compared to more advanced age, but is emerging as marking a possible shift in brain aging that is predictive of future cognitive health, while still being amenable to intervention.
Our recent review of the evidence is freely accessible here:
https://www.cell.com/trends/neurosciences/fulltext/S0166-2236(24)00017-1_returnURL=https%3A%2F%2Flinkinghub.elsevier.com%2Fretrieve%2Fpii%2FS0166223624000171%3Fshowall%3Dtrue​
Mapping human adult hippocampal neurogenesis with single-cell transcriptomics: Reconciling controversy or fueling the debate?
Single-cell RNA sequencing studies of the human hippocampus provide promising insight into whether adult neurogenesis exist in the human brain or not. In our recent Viewpoint published in the journal Neuron, we argue that the single-cell transcriptomic profiling of AHN in the human brain can be confounded by methodological, conceptual, and biological factors that need to be consistently addressed across studies and openly discussed within the scientific community.
The article is freely accessible here:https://www.sciencedirect.com/science/article/pii/S0896627323002064?via%3Dihub
A roadmap to understand the relevance of adult hippocampal neurogenesis for Alzheimer's disease
The first produce of our ongoing collaboration with the Salta Lab at the Netherlands Institute for Neuroscience is out.
In a perspectives article published in the journal Cell Stem Cell, we propose a possible roadmap to interpret the clinical relevance of adult hippocampal neurogenesis for Alzheimer's disease.
The article is freely accessible here:
https://www.sciencedirect.com/science/article/pii/S1934590923000024?via%3Dihub
piRNAs sustains neurogenesis in the postnatal hippocampus
In a new collaboration with the the Davide de Pietri Tonelli's lab at the Italian Institute of technology in Genoa, we show for the first time that the small RNAs generated by Piwi proteins (piRNAs) control neural stem cell differentiation toward a neural fate, cellular senescence, and the generation of reactive glia from them. These very novel observations have received online attention and have been highlighted in scientific news websites due to their relevance for neurodegenerative diseases and aging.
https://www.stemcellsciencenews.com/newsletter/198457/
A dream come(ing) true
June 2022
At the Fitzsimons Lab we dream to repair the brain, and now it seems we are starting to make this dream come true, almost complete prevention of cortex lesion development 14 days after an experimental traumatic brain injury in mice!
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Taumatic brain injury (TBI) is the leading cause of death in people younger than 45 years. Now, in an intrinsically collaborative work (42 authors, 16 research centers) we show for the first time that IL-2 delivery protects against neuroinflammation through the expansion of resident regulatory T cells in the brain, in a TBI model established in our lab a by Pascal Bielefeld in 2017.
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We are hoping this work moves soon into clinical trials as therapy for TBI, as the preclinical data is compelling.
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The paper is published in Nature Immunology and freely accessible here:
https://www.nature.com/articles/s41590-022-01208-z
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Simultaneous microRNA antagonist strategy highlighted
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May 2021
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Our recent work published in Frontiers in Molecular Neuroscience, describing how the simultaneous antagonism of both microRNA-124 and -137 can rescue seizure-induced alterations in neural stem cells of the adult hippocampus, has been selected by the Chief Editors to be featured in the Neuroplasticity and Development Editor’s Pick 2021 collection.
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Find this collection of interesting articles here.
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Two of our Mayor Biomedical Research projects, in collaboration with the Netherlands Institute for Neuroscience, have been financed by Alzheimer Nederland
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March 2021
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These two projects will lead to the recruitment of two Ph.D. students. The application for the positions is closed and candidates are currently been selected.
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Early life stress affects hypothalamic development
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January 28, 2021
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Our latest work is now published with full open access in Stress.
We show for the first time, the long-lasting effects of exposure to early life stress on cellular plasticity in the hypothalamus of adult mice.
The loss of stem cells and decreased proliferation we see, highlight how early life stress can affect hypothalamic functions in later life.
Read our work here:
Early life stress decreases cell proliferation and the number of putative adult neural stem cells in the adult hypothalamus.
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https://www.tandfonline.com/doi/full/10.1080/10253890.2021.1879787?src=&
A VERY EXCITING COLLABORATION
September 21, 2020
In collaboration with Davide de Pietri Tonelli's lab at IIT, we show in a new preprint that a new small RNA-mediated pathway in neural stem cells sustains adult neurogenesis by inhibiting protein synthesis
OUR PAPER IN THE NEWS!
September 2, 2020
Our work highlighted in Amsterdam Neuroscience's news bulletin!
https://www.amsterdamresearch.org/web/neuroscience/news/tonen-op-amsterdam-neuroscience/circadian-hormone-oscillations-preserve-a-population-of-neural-stem-cells-in-the-aging-brain.htm
OUR PAPER MADE IT TO THE COVER OF MOLECULAR PSYCHIATRY
June 2020
Our article is part of a broad collection of articles dedicated to the advances in depression research, recently published in Molecular Psychiatry:
"A superb article by Schouten et al.,..." ​
as reviewed by Licinio and Wong, Mol Psychiatry 25, 1356–1360 (2020). https://doi.org/10.1038/s41380-020-0798-1
EARLY LIFE STRESS DECREASES THE PROLIFERATION AND NUMBERS OF ADULT HYPOTHALAMIC NEURAL STEM CELLS.
November 5, 2019
Our new article describing for the first time the effects of early life stress on hypothalamic neural stem cells is now freely available on bioRxiv, have a look!
OURÂ ARTICLE IS PUBLISHED IN MOLECULAR PSYCHIATRY
June 2019
A decrease in adult hippocampal neurogenesis has been linked to age-related cognitive impairment. However, the mechanisms involved in this age-related reduction remain elusive. Here, we show that circadian oscillations in glucocorticoid hormones prevent neural stem cell activation and preserve a quiescent neural stem pool in the aging hippocampus that contributes to a neuroplasticity reserve in the aging brain.
The full text is accessible open-access following the link: