Astrocytes: Multitalented Stars of the Central Nervous System

Abstract

Astrocytes contribute to virtually every aspect of brain function, including ionic homeostasis, energy metabolism, and synaptic signaling. The varied and important roles of astrocytes have evolved to allow increasingly complex nervous systems to operate efficiently and with high fidelity. For example, astrocytes figure prominently in glutamatergic synaptic transmission, an elemental event of brain function: high-affinity glutamate uptake into astrocytes improves the temporal and spatial fidelity of glutamatergic signaling and astrocytes subsequently shuttle glutamine back to neurons for the synthesis of more glutamate. The important and dynamic contributions of astrocytes to normal brain function demand that the interactions between neurons and astrocytes be viewed as a "partnership," a harmonious collaboration to produce a desired function. The historical view of astrocytes as simple "support cells" is no longer valid and should be discarded. It is more accurate to view astrocytes as "partner cells." Future investigations of the intimate neuron-astrocyte partnership will require stringent and novel methodologies. This timely book on methodological approaches for studying astrocytes will provide modern neuroscientists with indispensable technical advice to help unravel the mysteries of the beautiful and successful marriage between astrocytes and neurons.

Calcium Signaling Involvement in Cadmium-Induced Astrocyte Cytotoxicity and Cell Death Through Activation of MAPK and PI3K/Akt Signaling Pathways

“…In vivo and in vitro studies have also indicated that acute or chronic exposure to Cd causes death in neurons, including apoptosis and necrosis [23,24]. It's well known that astrocytes perform a very important role in the pathology and physiology of CNS function, including a protective role in neuronal survival and tissue repair after CNS injury via cleaning up metabolic toxins and free radicals [12,25]. Previous study mainly focused on the Cd toxicity to neurons, now it's very necessary to investigate the astrocytic response to Cd in addition to the neuronal response, so as to get a comprehensive understanding of the CNS response to a toxin.…”

Resveratrol Protects Hippocampal Astrocytes Against LPS-Induced Neurotoxicity Through HO-1, p38 and ERK Pathways

“…Astrocytes contribute to maintenance of synaptic information processing and ionic homeostasis; regulate energy metabolism and release of neurotrophic factors; modulate the biosynthesis and release of antioxidant defenses and the main anti-and proinflammatory cytokines [2][3][4][5][6][7][8]. Although immune responses in the CNS are mainly attributed to microglia, due to the capacity of these cells to present antigens, astrocytes express tolllike receptors (TLR) and build up responses to immune triggers by releasing proinflammatory molecules [9,10].…”

Gliopreventive effects of guanosine against glucose deprivation in vitro

“…Specifically, astrocytes regulate the metabolic support of neurons, energy metabolism, neurotransmitter systems, ionic homeostasis, and the defense against oxidative stress. In addition, astrocytes can play a protective role by releasing neurotrophic factors [24][25][26][27][28][29][30]. Astrocytes are also the primary cells responsible for glutamate transport into glial cells, maintaining glutamate homeostasis within the brain and contributing to the maintenance of extracellular concentration of glutamate below toxic levels, thus avoiding glutamatergic excitotoxicity [27,28,[31][32][33].…”