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Neurogenesis and regeneration in the primary olfactory pathway of mammals.

The primary sensory neurons in the olfactory and vomeronasal mucosae develop outside the neuraxis from ectodermal placodes, and their axons enter the central nervous system (CNS) during embryonic life, to terminate in the olfactory and accessory olfactory bulbs. The sensory neurons are unique in that they are produced and differentiate continuously from a stem cell in the sensory epithelium, throughout the life of the animal. After loss of sensory neurons following injury, the stem cell is able to increase its rate of division and replace the lost neurons. Sensory neurons thus formed during ad

Unequal mitochondrial segregation promotes asymmetric fates during neurogenesis.

Asymmetric cell division plays a critical role during vertebrate neurogenesis by generating neuronal cells while maintaining a pool of progenitors. It relies on unequal distribution of cell fate determinants during progenitor division. Here, we use live imaging in the chick embryonic neuroepithelium to demonstrate that mitochondria behave as asymmetric fate determinants during mitosis. We show that the frequency of unequal distribution of mitochondria increases in parallel with the rate of asymmetric divisions during development. Furthermore, fate tracking experiments reveals that following pr…

Human SPG11 cerebral organoids reveal cortical neurogenesis impairment.

Spastic paraplegia gene 11(SPG11)-linked hereditary spastic paraplegia is a complex monogenic neurodegenerative disease that in addition to … an increased rate of asymmetric divisions of NPCs leads to proliferation defect, causing premature neurogenesis. Correspondingly, SPG11 organoids appeared smaller than controls and had larger ventricles as well as thinner germinal wall. Premature neurogenesis and organoid size were rescued by GSK3 inhibititors including the Food and Drug Administration-approv …

NEIL1 stimulates neurogenesis and suppresses neuroinflammation after stress.

Cellular exposure to ionizing radiation leads to oxidatively generated DNA damage, which has been implicated in neurodegenerative diseases. DNA damage is repaired by the evolutionarily conserved base excision repair (BER) system. Exposure of mice to ionizing radiation affects neurogenesis and neuroinflammation. However, the consequences of deficient DNA repair on adult neurogenesis and neuroinflammation are poorly understood despite their potential relevance for homeostasis. We previously reported that loss of NEIL1, an important DNA glycosylase involved in BER, is associated with deficiencies…

Accelerated Tempo of Cortical Neurogenesis in Down Syndrome.

Down syndrome (DS), caused by trisomy 21 (TS21), is the most common genetic cause of intellectual disability1,2. The neurological impacts of DS first manifest during prenatal development through reduced radial glia (RG) neural stem cell proliferation, reduced cortical volume and imbalanced cortical cell types3-6. However, the developmental mechanisms underlying altered cortical neurogenesis in DS remain elusive. Here we show by high-throughput lineage tracing in organotypic culture that TS21 accelerates RG lineage progression, driving premature production of cortical inhibitory neurons (INs) a…

AAV ablates neurogenesis in the adult murine hippocampus.

Recombinant adeno-associated virus (rAAV) has been widely used as a viral vector across mammalian biology and has been shown to be safe and … t, with loss of BrdU-labeled cells within 18 hr post-injection and no evidence of recovery of adult neurogenesis at 3 months post-injection. The remaining mature DGCs appear hyperactive 4 weeks post-injection based on immediate early gene expression, consistent with previous studies investigating the effects of attenuating adult neurogenesis. In vitro applicat …

An Overview of Nicotinic Cholinergic System Signaling in Neurogenesis.

The production of new neurons continues in the adult mammalian brain because of the sustained proliferation and differentiation of neural stem cells (NSCs) in neurogenic regions. The subventricular zone (SVZ), lining the lateral ventricle, and the subgranular zone (SGZ), which is in the dentate gyrus (DG) of the hippocampus, are the central regions of neurogenesis in the brain. Neurogenesis brings great hope for repairing a damaged brain and motivates researchers to detect the controlling signals of this process. Neurogenesis is regulated by intracellular and extracellular mechanisms that are …

The role of neurogenesis in neurorepair after ischemic stroke.

Stroke consists of an abrupt reduction of cerebral blood flow resulting in hypoxia that triggers an excitotoxicity, oxidative stress, and neuroinflammation. After the ischemic process, neural precursor cells present in the subventricular zone of the lateral ventricle and subgranular zone of the dentate gyrus proliferate and migrate towards the lesion, contributing to the brain repair. The neurogenesis is induced by signal transduction pathways, growth factors, attractive factors for neuroblasts, transcription factors, pro and anti-inflammatory mediators and specific neurotransmissions. However…

Neurogenesis in Neurodegenerative Diseases: Role of MFG-E8.

Neurodegenerative diseases are devastating medical conditions with no effective treatments. Restoration of impaired neurogenesis represents a promising therapeutic strategy for neurodegenerative diseases. Milk fat globule-epidermal growth factor-factor VIII (MFG-E8) is a secretory glycoprotein that plays a wide range of cellular functions including phagocytosis of apoptotic cells, anti-inflammation, tissue regeneration, and homeostasis. The beneficial role of MFG-E8 has been shown in cerebral ischemia (stroke), neurodegenerative diseases such as Alzheimer's disease and Parkinson's disease, and…

No pain, no gain: lack of exercise obstructs neurogenesis.

Bedridden patients develop atrophied muscles, their daily activities greatly reduced, and some display a depressive mood. Patients who are able to receive physical rehabilitation sometimes show surprising clinical improvements, including reduced depression and attenuation of other stress-related behaviors. Regenerative medicine has advanced two major stem cell-based therapies for CNS disorders, namely, transplantation of exogenous stem cells and amplification of endogenous neurogenesis. The latter strategy embraces a natural way of reinnervating the damaged brain and correcting the neurologica…

Временная динамика гиппокампального нейрогена в хроническом нейродегенерации.

Изучение нейрогенеза во время хронического нейродегенерации имеет решающее значение для понимания внутренних механизмов ремонта мозга и для разработки терапевтических стратегий. В этом исследовании, в котором используется экспериментальная модель прогрессивного хронического нейродегенерации, заболевания мюрин-приона, определяется временная динамика образования, созревания и интеграции новых нейронов в гиппокампальный оденат, с использованием двойного импульса-зазора, многоцветного ретровирусного отслеживания, электронной микроскопии и патрубка. Мы обнаружили повышенный нейрогенесис во время ра

Совпадение в аннотации оригинала
The study of neurogenesis during chronic neurodegeneration is crucial in order to understand the intrinsic repair mechanisms of the brain, and key to designing therapeutic strategies. In this study, using an experimental model of progressive chronic neurodegeneration, murine prion disease, we define the temporal dynamics of the generation, maturation and int…

N-acetylserotonin: neuroprotection, neurogenesis, and the sleepy brain.

N-Acetylserotonin (NAS) is a naturally occurring chemical intermediate in biosynthesis of melatonin. Previous studies have shown that NAS has different brain distribution patterns from those of serotonin and melatonin, suggesting that NAS might have functions other than as a precursor or metabolite of melatonin. Indeed, several studies have now shown that NAS may play an important role in mood regulation and may have antidepressant activity. Additional studies have shown that NAS stimulates proliferation of neuroprogenitor cells and prevents some of the negative effects of sleep deprivation. I

A role for FE65 in controlling GnRH-1 neurogenesis.

Gonadotropin-releasing hormone-1 (GnRH-1) neurons migrate from the nasal placode to the forebrain where they control gonadal function via th … rotein signaling has been described in neuro/glial cell fate determination as well as in modulating neurogenesis. Analysis of two mouse lines, one deficient for the 97 kDa FE65 isoform and a second deficient for the 97 and 60 kDa forms of FE65, showed overlapping phenotypes. In both lines, no migratory defects of the GnRH-1 neurons were observed, but a 25% inc …

Noise trauma impairs neurogenesis in the rat hippocampus.

The hippocampus, a major site of neurogenesis in the adult brain, plays an important role in memory. Based on earlier observations where exposure to high-intensity noise not only caused hearing loss but also impaired memory function, it is conceivably that noise exposure may suppress hippocampal neurogenesis. To evaluate this possibility, nine rats were unilaterally exposed for 2 h to a high-intensity, narrow band of noise centered at 12 kHz at 126 dB SPL. The rats were also screened for noise-induced tinnitus, a potential stressor which may suppress neurogenesis. Five rats developed persisten…

Notch signaling and neurogenesis in normal and stroke brain.

Adult neuronal stem cells (NSCs) hold great promise for brain repair because of their unique location within the central nervous system, the … articularly in the aged brain. Therefore, to further define the regulatory mechanisms that underlie neurogenesis after stroke, it is critically important to develop future NSC-based repair strategies. Notch signaling defines a fundamental pathway controlling cell fate acquisition. Studies have shown that Notch signaling pathways play critical roles during the …

[Neurogenesis in the adult brain: from bench to bedside?].

Two regions of the mammalian brain maintain the capability to generate new neurons throughout lifetime: Neuronal stem- and precursor cells proliferate in the subgranulare zone (SGZ) of the dentate gyrus in the hippocampus and in the subventricular zone (SVZ) of the lateral ventricles to give rise to new neurons that are functionally integrated into the neural network. The functional relevance of adult neurogenesis under physiological conditions on one hand, and the newly discovered potentiality of cellular regeneration in the diseased brain on the other hand, arouse the interest of fundamental…

Neurogenesis in the adult brain: implications for Alzheimer's disease.

The function of neurogenesis in the adult brain is still unknown. Interventions such as environmental enrichment and exercise impinge on neurogenesis, suggesting that the process is regulated by experience. Conversely, a role for neurogenesis in learning has been proposed through 'cellular plasticity', a process akin to synaptic plasticity but operating at the network level. Although neurogenesis is stimulated by acute injury, and possibly by neurodegenerative processes such as Alzheimer's disease (AD), it does not suffice to restore function. While the role and direction of change in the neur…

The amyloid precursor protein and postnatal neurogenesis/neuroregeneration.

The amyloid precursor protein (APP) is the source of amyloid-beta (Abeta) peptide, produced via its sequential cleavage beta- and gamma-secretases. Various biophysical forms of Abeta (and the mutations of APP which results in their elevated levels) have been implicated in the etiology and early onset of Alzheimer's disease. APP's evolutionary conservation and the existence of APP-like isoforms (APLP1 and APLP2) which lack the Abeta sequence, however, suggest that these might have important physiological functions that are unrelated to Abeta production. Soluble N-terminal fragments of APP have

Growth factors induce neurogenesis in the ciliary body.

The ciliary body of the eye is a nonneural tissue that is derived from the anterior rim of the optic cup, an extension of the neural tube. T … ur results suggest that the ciliary body has the capacity to generate retinal neurons, but normally neurogenesis is actively inhibited.