Tracking cell turnover in human brain using 15N-thymidine imaging mass spectrometry

Frontiers in Neuroscience

Neuroscience

Olaf Bergmann¹  Anton B. Tonchev²  Elisabet Englund³  Christoph Daniel⁴  Kerstin Amann⁴  Elisa A. Bonnin⁵  Silvio O. Rizzoli⁵  Thorsten R. Döppner⁶  Stefan Schwab⁷  Stephanie Gollwitzer⁷  Hajo M. Hamer⁷  Sebastian S. Roeder⁸  Hagen B. Huttner⁹  Stefan T. Gerner⁹  Samir Jabari^1,10  Sebastian Brandner^1,11  Ilker Y. Eyüpoglu^1,12  Karl Roessler^1,13  Ursula Schlötzer-Schrehardt^1,14  Christoph Rummel^1,15  Jean-Luc Guerquin-Kern^1,16  Ting-Di Wu^1,16  Tobias Borst^1,17  Ralph Heimke-Brinck^1,17 

[1] Center for Regenerative Therapies, Technische Universität Dresden, Dresden, Germany;Department of Cell and Molecular Biology, Karolinska Institute, Stockholm, Sweden;Institute of Pharmacology and Toxicology, Universitätsmedizin Göttingen, Göttingen, Germany;Department of Anatomy and Cell Biology and Stem Cell Biology Research Institute, Medical University Varna, Varna, Bulgaria;Department of Clinical Sciences, University of Lund, Lund, Sweden;Department of Nephropathology, Institute of Pathology, Friedrich-Alexander-University Erlangen-Nuremberg, Erlangen, Germany;Department of Neuro- and Sensory Physiology, University Medical Center Göttingen, Excellence Cluster Multiscale Bioimaging, Center for Biostructural Imaging of Neurodegeneration, Göttingen, Germany;Department of Neurology, Justus Liebig University, Gießen, Germany;Department of Neurology, University of Erlangen-Nuremberg, Erlangen, Germany;Department of Neurology, University of Erlangen-Nuremberg, Erlangen, Germany;Center for Regenerative Therapies, Technische Universität Dresden, Dresden, Germany;Department of Neurology, University of Erlangen-Nuremberg, Erlangen, Germany;Department of Neurology, Justus Liebig University, Gießen, Germany;Department of Neuropathology, University of Erlangen-Nuremberg, Erlangen, Germany;Department of Neurosurgery, University of Erlangen-Nuremberg, Erlangen, Germany;Department of Neurosurgery, University of Erlangen-Nuremberg, Erlangen, Germany;Department of Neurosurgery, Technische Universität Dresden, Dresden, Germany;Department of Neurosurgery, University of Erlangen-Nuremberg, Erlangen, Germany;Department of Neurosurgery, University of Vienna, Vienna, Austria;Department of Ophthalmology, University Hospital, Friedrich-Alexander-University Erlangen-Nuremberg, Erlangen, Germany;Department of Veterinary Physiology and Biochemistry, Justus Liebig University, Gießen, Germany;Institut Curie, PSL University, Université Paris-Saclay, CNRS UAR2016, Inserm US-43, Multimodal Imaging Center, Paris, France;Pharmacy, University of Erlangen-Nuremberg, Erlangen, Germany;

关键词: neurogenesis;    adult;    hippocampus;    cell turnover;    glioblastoma;    Nano-SIMS;    DNA-labeling;   

DOI  :  10.3389/fnins.2023.1274607

 received in 2023-08-08, accepted in 2023-09-04,  发布年份 2023

来源: Frontiers

【 摘 要 】

Microcephaly is often caused by an impairment of the generation of neurons in the brain, a process referred to as neurogenesis. While most neurogenesis in mammals occurs during brain development, it thought to continue to take place through adulthood in selected regions of the mammalian brain, notably the hippocampus. However, the generality of neurogenesis in the adult brain has been controversial. While studies in mice and rats have provided compelling evidence for neurogenesis occurring in the adult rodent hippocampus, the lack of applicability in humans of key methods to demonstrate neurogenesis has led to an intense debate about the existence and, in particular, the magnitude of neurogenesis in the adult human brain. Here, we demonstrate the applicability of a powerful method to address this debate, that is, the in vivo labeling of adult human patients with 15N-thymidine, a non-hazardous form of thymidine, an approach without any clinical harm or ethical concerns. 15N-thymidine incorporation into newly synthesized DNA of specific cells was quantified at the single-cell level with subcellular resolution by Multiple-isotype imaging mass spectrometry (MIMS) of brain tissue resected for medical reasons. Two adult human patients, a glioblastoma patient and a patient with drug-refractory right temporal lobe epilepsy, were infused for 24 h with 15N-thymidine. Detection of 15N-positive leukocyte nuclei in blood samples from these patients confirmed previous findings by others and demonstrated the appropriateness of this approach to search for the generation of new cells in the adult human brain. 15N-positive neural cells were easily identified in the glioblastoma tissue sample, and the range of the 15N signal suggested that cells that underwent S-phase fully or partially during the 24 h in vivo labeling period, as well as cells generated therefrom, were detected. In contrast, within the hippocampus tissue resected from the epilepsy patient, none of the 2,000 dentate gyrus neurons analyzed was positive for 15N-thymidine uptake, consistent with the notion that the rate of neurogenesis in the adult human hippocampus is rather low. Of note, the likelihood of detecting neurogenesis was reduced because of (i) the low number of cells analyzed, (ii) the fact that hippocampal tissue was explored that may have had reduced neurogenesis due to epilepsy, and (iii) the labeling period of 24 h which may have been too short to capture quiescent neural stem cells. Yet, overall, our approach to enrich NeuN-labeled neuronal nuclei by FACS prior to MIMS analysis provides a promising strategy to quantify even low rates of neurogenesis in the adult human hippocampus after in vivo15N-thymidine infusion. From a general point of view and regarding future perspectives, the in vivo labeling of humans with 15N-thymidine followed by MIMS analysis of brain tissue constitutes a novel approach to study mitotically active cells and their progeny in the brain, and thus allows a broad spectrum of studies of brain physiology and pathology, including microcephaly.

【 授权许可】

Unknown   
Copyright © 2023 Roeder, Bonnin, Wu, Guerquin-Kern, Jabari, Brandner, Eyüpoglu, Gollwitzer, Hamer, Gerner, Döppner, Rummel, Englund, Heimke-Brinck, Borst, Daniel, Amann, Schlötzer-Schrehardt, Tonchev, Roessler, Schwab, Bergmann, Rizzoli and Huttner.