Discerning Neurogenic vs. Non-Neurogenic Postnatal Lateral Ventricular Astrocytes via Activity-Dependent Input.
Discerning Neurogenic vs. Non-Neurogenic Postnatal Lateral Ventricular Astrocytes via Activity-Dependent Input.
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DOI：
10.3389/fnins.2016.00111
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发表时间：
2016
影响因子：
4.3
通讯作者：
Kuo CT
中科院分区：
文献类型：
--
作者：
Adlaf EW;Mitchell-Dick A;Kuo CT
在整个发育过程中，神经干细胞（NSC）产生分化的神经元、星形胶质细胞和少突胶质细胞，它们共同调节成人神经系统中的感知、记忆和行为。为了了解神经干细胞如何促进出生后/成人脑重塑和损伤后修复，啮齿动物出生后脑中的侧脑室（LV）神经原性生态位是一个很好的模型系统。它是一个专门的区域，含有自我更新的GFAP+星形胶质细胞，其功能是在整个生命中产生新神经元的NSC。除了这个现在被充分研究的再生过程之外，LV龛还产生分化的星形胶质细胞，在皮质损伤后的胶质瘢痕形成中发挥重要作用。虽然LV NSC可以通过分子标记与其神经母细胞和少突胶质细胞后代明确区分，但NSC的星形胶质细胞身份使其与利基中终末分化的星形胶质细胞的区分变得复杂。我们目前的出生后/成年LV神经发生模型没有考虑到局部星形细胞发生，或者细胞标志物在非分裂GFAP+ NSC和其分化的星形胶质细胞子代之间可能相似的可能性。出生后LV神经发生受与细胞外/小生境驱动的线索相互作用的NSC-intrinsic机制调节。一般认为，这些局部效应是维持神经发生的原因，尽管行为模式和疾病状态表明了神经回路水平调制的可能性。最近的实验发现，神经元刺激可以直接引起反应，在LV神经干细胞，这是可能的，这种令人兴奋的属性将增加一个新的层面，以确定出生后/成人神经干细胞。在这里，我们提出了一个概念，神经回路水平的输入可以是一个独特的特征，定义出生后/成人神经干细胞从非神经源性星形胶质细胞。
Throughout development, neural stem cells (NSCs) give rise to differentiated neurons, astrocytes, and oligodendrocytes which together modulate perception, memory, and behavior in the adult nervous system. To understand how NSCs contribute to postnatal/adult brain remodeling and repair after injury, the lateral ventricular (LV) neurogenic niche in the rodent postnatal brain serves as an excellent model system. It is a specialized area containing self-renewing GFAP+ astrocytes functioning as NSCs generating new neurons throughout life. In addition to this now well-studied regenerative process, the LV niche also generates differentiated astrocytes, playing an important role for glial scar formation after cortical injury. While LV NSCs can be clearly distinguished from their neuroblast and oligodendrocyte progeny via molecular markers, the astrocytic identity of NSCs has complicated their distinction from terminally-differentiated astrocytes in the niche. Our current models of postnatal/adult LV neurogenesis do not take into account local astrogenesis, or the possibility that cellular markers may be similar between non-dividing GFAP+ NSCs and their differentiated astrocyte daughters. Postnatal LV neurogenesis is regulated by NSC-intrinsic mechanisms interacting with extracellular/niche-driven cues. It is generally believed that these local effects are responsible for sustaining neurogenesis, though behavioral paradigms and disease states have suggested possibilities for neural circuit-level modulation. With recent experimental findings that neuronal stimulation can directly evoke responses in LV NSCs, it is possible that this exciting property will add a new dimension to identifying postnatal/adult NSCs. Here, we put forth a notion that neural circuit-level input can be a distinct characteristic defining postnatal/adult NSCs from non-neurogenic astroglia.