Myelin is an evolutionarUy novel and important structure for the proper functioning of the vertebrate nervous system. In the central nervous system （CNS）, the myelin sheath is elaborated by oligodendrocytes, and is ...Myelin is an evolutionarUy novel and important structure for the proper functioning of the vertebrate nervous system. In the central nervous system （CNS）, the myelin sheath is elaborated by oligodendrocytes, and is composed of multiple layers of specialized cell membrane wrapping around axons with periodic interruptions at the nodes of Ranvier. The major function of the myelin sheath is to provide ionic insulation to ensure rapid and saltatory conduction of electrical pulses along axons. In addition, myelin provides neurotrophic support for axons, as they become increasingly dependent on myelin-derived signals for survival. Despite the importance of myelin in the functioning of the CNS, oligodendrocytes are particularly susceptible to genetic and environmental perturbations, and demyelination can be triggered by many pathological conditions including traumatic injury, autoimmune disease （multiple sclerosis, MS）, heavy metal toxicity, and hypoxia. Loss of myelin sheaths in the CNS not only results in the compromised conduction of electrical signals, but also causes progressive degeneration of axons and ultimately neuronal loss. Spontaneous myelin repair from immature oligodendrocyte progenitor cells （OPCs） is not effective in demyelinating lesions, due either to the absence of stimulatory developmental signals that are no longer produced in the adult environment, or to the presence of inhibitory factors peculiar to this environment.展开更多
Emerging evidence is fueling a new appreciation of oligodendrocyte diversity that is overturning the traditional view that oligodendrocytes are a homogenous cell population.Oligodendrocytes of distinct origins,maturat...Emerging evidence is fueling a new appreciation of oligodendrocyte diversity that is overturning the traditional view that oligodendrocytes are a homogenous cell population.Oligodendrocytes of distinct origins,maturational stages,and regional locations may differ in their functional capacity or susceptibility to injury.One of the most unique qualities of the oligodendrocyte is its ability to produce myelin.Myelin abnormalities have been ascribed to a remarkable array of perinatal brain injuries,with concomitant oligodendrocyte dysregulation.Within this review,we discuss new insights into the diversity of the oligodendrocyte lineage and highlight their relevance in paradigms of perinatal brain injury.Future therapeutic development will be informed by comprehensive knowledge of oligodendrocyte pathophysiology that considers the particular facets of heterogeneity that this lineage exhibits.展开更多
文摘Myelin is an evolutionarUy novel and important structure for the proper functioning of the vertebrate nervous system. In the central nervous system （CNS）, the myelin sheath is elaborated by oligodendrocytes, and is composed of multiple layers of specialized cell membrane wrapping around axons with periodic interruptions at the nodes of Ranvier. The major function of the myelin sheath is to provide ionic insulation to ensure rapid and saltatory conduction of electrical pulses along axons. In addition, myelin provides neurotrophic support for axons, as they become increasingly dependent on myelin-derived signals for survival. Despite the importance of myelin in the functioning of the CNS, oligodendrocytes are particularly susceptible to genetic and environmental perturbations, and demyelination can be triggered by many pathological conditions including traumatic injury, autoimmune disease （multiple sclerosis, MS）, heavy metal toxicity, and hypoxia. Loss of myelin sheaths in the CNS not only results in the compromised conduction of electrical signals, but also causes progressive degeneration of axons and ultimately neuronal loss. Spontaneous myelin repair from immature oligodendrocyte progenitor cells （OPCs） is not effective in demyelinating lesions, due either to the absence of stimulatory developmental signals that are no longer produced in the adult environment, or to the presence of inhibitory factors peculiar to this environment.
文摘Emerging evidence is fueling a new appreciation of oligodendrocyte diversity that is overturning the traditional view that oligodendrocytes are a homogenous cell population.Oligodendrocytes of distinct origins,maturational stages,and regional locations may differ in their functional capacity or susceptibility to injury.One of the most unique qualities of the oligodendrocyte is its ability to produce myelin.Myelin abnormalities have been ascribed to a remarkable array of perinatal brain injuries,with concomitant oligodendrocyte dysregulation.Within this review,we discuss new insights into the diversity of the oligodendrocyte lineage and highlight their relevance in paradigms of perinatal brain injury.Future therapeutic development will be informed by comprehensive knowledge of oligodendrocyte pathophysiology that considers the particular facets of heterogeneity that this lineage exhibits.
