Recommendable! When old, obsolete scientific dogmas die hard!
I feel already much better as an old dude! 😊
"... Now, an AI-powered study may finally have settled the debate by identifying neural progenitor cells in adult hippocamp[us].
More than a century ago, Santiago Ramon y Cajal—the “father of neuroscience”—declared that nerve cells are “fixed, ended, and immutable” after development. Ever since, scientists have generally assumed that he was correct and that neurogenesis stopped abruptly after childhood. ...
In the 1990s and 2000s, even more research challenged this assumption, finding what appeared to be actively dividing cells—known as neural progenitors—in the adult human brain. Still, some neuroscientists remained unpersuaded. ..."
"Challenging the long-held dogma that the generation of neurons ends in mammals early after birth, pioneering papers in the 1960s suggested that new neurons are born in the rodent brain throughout life.
These adult-born neurons were detected in several regions, including the hippocampus, which is important for learning, memory, and mood control and is impaired in diseases such as Alzheimer’s disease.
From this emerged a decades-long controversy, with numerous studies providing evidence for—or against—the lifelong activity of neural progenitor cells (NPCs) as a source of newborn neurons in the human hippocampus. ... Dumitru et al. (1) report the use of single-nucleus RNA sequencing (snRNA-seq) and spatial transcriptomics to identify cells with transcriptional signatures of NPCs and newborn neurons in the human hippocampus from childhood to old age. Together with previous work (2–4), the findings indicate that neurogenesis persists throughout life in the human hippocampus."
From the editor's note and the abstract:
"Editor’s summary
Whether adult neurogenesis occurs in the human hippocampus is one of the most debated issues in neuroscience. Dumitru et al. used a single-cell transcriptomic approach to address this issue in human samples of various ages from birth through adulthood ... Machine learning algorithms helped the authors to identify proliferating neural progenitor cells in the adolescent and adult human hippocampus that resembled progenitor cells found in mouse and pig. The results support the idea that adult neurogenesis occurs in the human hippocampus and add valuable insights of scientific and medical interest. ...
Abstract
Continuous adult hippocampal neurogenesis is involved in memory formation and mood regulation but is challenging to study in humans. Difficulties finding proliferating progenitor cells called into question whether and how new neurons may be generated. We analyzed the human hippocampus from birth through adulthood by single-nucleus RNA sequencing.
We identified all neural progenitor cell stages in early childhood.
In adults, using antibodies against the proliferation marker Ki67 and machine learning algorithms, we found proliferating neural progenitor cells.
Furthermore, transcriptomic data showed that neural progenitors were localized within the dentate gyrus. The results contribute to understanding neurogenesis in adult humans."
Sequenced evidence "Transcriptome analyses identify neural progenitor cells in the adult human hippocampus"
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