外胚葉由来の器官の発生：表皮、脳神経系、眼

外胚葉由来の器官の発生

  1. Embryology | Ectoderm (24:03) Ninja Nerd チャンネル登録者数 288万人

表皮の発生

脳神経系の構造

  1. Introduction to Neuroanatomy – Learn the Basics – Neuroanatomy Playlist（３２：２６） Medicosis Perfectionalis チャンネル登録者数 109万人
  2. 2-Minute Neuroscience: Myelin Neuroscientifically Challenged チャンネル登録者数 52.8万人

脳神経系の発生

神経系はすべて外胚葉由来ですが、細かくみると、中枢神経系は神経管に由来します。一方、末梢神経系は神経堤細胞(neural crest cells)に由来します。

During vertebrate development, the central (CNS) and peripheral nervous systems (PNS) arise from the neural plate. Cells at the margin of the neural plate give rise to neural crest cells, which migrate extensively throughout the embryo, contributing to the majority of neurons and all of the glia of the PNS. The rest of the neural plate invaginates to form the neural tube, which expands to form the brain and spinal cord.

From classical to current: analyzing peripheral nervous system and spinal cord lineage and fate　Dev Biol. 2015 Feb 15; 398(2): 135–146.　PMCID: PMC4845735

  1. 2-Minute Neuroscience: Early Neural development (1:59) Neuroscientifically Challenged チャンネル登録者数 52.8万人
  2. Embryology of the Nervous System | Development of CNS & PNS (14:31) Medicosis Perfectionalis チャンネル登録者数 109万人 神経発生の解説が始まるのは5:04から　末梢神経系の神経細胞の軸索は、神経(nerve)と呼ばれます。
  3. General Embryology – Detailed Animation On Neurulation Medical Animations 167K subscribers (1:49)
  4. Embryology | Neurulation, Vesiculation, Neural Crest Cell Migration Ninja Nerd 2.88M subscribers (34:17)
  5. Embryology of the Nervous System | Development of CNS & PNS Medicosis Perfectionalis チャンネル登録者数 109万人 (14:31

 

神経誘導の講義動画は形態の変化を説明したものが多いですが、形態の変化を引き起こしていいるのは遺伝子によって巧妙に制御された分子シグナリングです。

別記事→　神経誘導の分子シグナリング

Generation of cortical neurons

Arnold Kriegstein (UCSF) 1: Outer Subventricular Zone Radial Glia Cells – Brain Development Science Communication Lab チャンネル登録者数 17.7万人

10:20- single-labelled subcortical cells time lapse imaging

11:43 “we were very lucky at UCSF to get donated tissue”

*Gestational age is measured in weeks, from the first day of the woman’s last menstrual cycle to the current date. https://medlineplus.gov/ency/article/002367.htm

  1. Arnold Kriegstein (UCSF) 1: Outer Subventricular Zone Radial Glia Cells – Brain Development (31:04) Science Communication Lab チャンネル登録者数 17.7万人 Lecture
  2. Arnold Kriegstein – Genomic insights into human brain development, evolution, and disease  (43:54) Columbia University’s Zuckerman Institute チャンネル登録者数 4620人 Lecture
  3. CARTA: Livesey-Primate Brain Development; Huttner-Neocortex Expansion; Kriegstein-Brain Expansion (58:27) University of California Television (UCTV) チャンネル登録者数 130万人

主要な原著論文

  1. David V. Hansen, Jan H. Lui, Philip R. L. Parker & Arnold R. Kriegstein. Neurogenic radial glia in the outer subventricular zone of human neocortex. Nature 464, 554–561 (2010). https://doi.org/10.1038/nature08845
  2. Stephen C. Noctor, Alexander C. Flint, Tamily A. Weissman, Ryan S. Dammerman & Arnold R. Kriegstein. Neurons derived from radial glial cells establish radial units in neocortex. Nature 409, 714–720 (2001). https://doi.org/10.1038/35055553 (全文は有料） It has been suggested that radial glia may be neuronal precursors, but this has not been demonstrated in vivo. We have used a retroviral vector encoding enhanced green fluorescent protein to label precursor cells in vivo and have examined clones 1–3 days later using morphological, immunohistochemical and electrophysiological techniques. Here we show that clones consist of mitotic radial glia and postmitotic neurons, and that neurons migrate along clonally related radial glia. Time-lapse images show that proliferative radial glia generate neurons.

眼の発生

retinotopic mapの形成

axon guidance

 

Sensitive period

Plasticity

  1. Rewiring the Brain: The Promise and Peril of Neuroplasticity (1:26:29) World Science Festival チャンネル登録者数 123万人

 

神経新生

成人の脳ではあらたに神経細胞（ニューロン）がつくられることはないと長い間信じられてきて医学部の学部教育でもそう教えられてきましたが、その常識は最近覆りました。脳の一部の領域ではニューロンが成人の脳でも作られていることが発見されたのです。ニューロンが新生する(neurogenesis)領域の一つが海馬で、もうひとつがsubventricular zone (SVZ)と呼ばれる領域です。

Adult neurogenesis, the process of creating new neurons, involves the coordinated division, migration, and differentiation of neural stem cells. This process is restricted to neurogenic niches located in two distinct areas of the brain: the subgranular zone of the dentate gyrus of the hippocampus and the subventricular zone of the lateral ventricle, where new neurons are generated and then migrate to the olfactory bulb.

  • 1960s New neurons could be generated in the DG and SVZ of the adult brain in cat and rat models (Altman, 1962, 1963; Altman and Das, 1965)
  • 1989 Adult brain neurogenesis in songbirds (Nottebohm, 1989).
  • 1998 Neurogenesis in the adult human hippocampus (in the postmortem tissue of cancer patients) (Eriksson et al., Nat Med. 1998 Nov;4(11):1313-7. ).
  • 1999 Adult macaque monkeys neurogenesis ten times lower than that of rodents (Gould et al., 1999)
  • 2013 carbon dating techniques to determine that the human DG adds up to 700 neurons per day (Spalding et al., 2013)
    • Kheirbek MA, Hen R. (Radio)active neurogenesis in the human hippocampus. Cell. 2013 Jun 6;153(6):1183-4. doi: 10.1016/j.cell.2013.05.033. PMID: 23746833; PMCID: PMC4046854. (Author manuscript)
  • 2018 studies using carbon 14 can produce unreliable results and are prone to noise and contamination (Sorrells et al., 2018).

Hussain et al. Adult neurogenesis: a real hope or a delusion? Neural Regen Res. 2024 Jan;19(1):6-15. doi: 10.4103/1673-5374.375317. PMCID: PMC10479850.

  1. Adult Neurogenesis – Alfredo Quiñones-Hinojosa (Johns Hopkins/HHMI) (5:09) iBiology Techniques チャンネル登録者数 7.21万人

総説論文

  1. Adult Neurogenesis ScienceDirect
  2. Zhang et al. Neurogenesis in primates versus rodents and the value of non-human primate models. National Science Review, Volume 10, Issue 11, November 2023, nwad248, https://doi.org/10.1093/nsr/nwad248
  3. The Adult Ventricular–Subventricular Zone (V-SVZ) and Olfactory Bulb (OB) Neurogenesis Daniel A. Lim and Arturo Alvarez-Buylla Cold Spring Harb Perspect Biol. 2016 May; 8(5): a018820. doi: 10.1101/cshperspect.a018820 PMCID: PMC4852803

参考

  1. Adult Hippocampal Neurogenesis: Growing New Brain Cells as an Adult (8:52) Maria Conley MD チャンネル登録者数 5220人
  2. Stem cells and adult neurogenesis EuroGCT and EuroStemCell チャンネル登録者数 8220人
  3. You can grow new brain cells. Here’s how | Sandrine Thuret | TED TED チャンネル登録者数 2410万人

神経系の再生医療

  1. How can we repair damaged axons? Science Animated チャンネル登録者数 2.87万人
  2. Can we repair injured nerves? | Massimo Hilliard | TEDxUQ TEDx Talks チャンネル登録者数 4030万人

脳オルガノイド

Brain Organoids 101 Harvard Brain Science Initiative チャンネル登録者数 1980人

  1. Arnold Kriegstein (UCSF) 2: Cerebral Organoids: Models of Human Brain Disease and Evolution （32:57）Science Communication Lab チャンネル登録者数 17.7万人
  2. Brain Organoids 101 (1:12:56) Harvard Brain Science Initiative チャンネル登録者数 1980人
  3. Facilitating Cerebral Organoid Culture via Lateral Soft Light Illumination DOI : 10.3791/63989-v • 9:10 min • June 6th, 2022 JoVE
  4. Generation of Human Brain Organoids for Mitochondrial Disease Modeling DOI : 10.3791/62756-v • 8:09 min • June 21st, 2021 JoVE
  5. Three-Dimensional Motor Nerve Organoid Generation DOI : 10.3791/61544-v • 9:57 min • September 24th, 2020 JoVE