Astrocyte - Recent Studies

Recent Studies

A recent study, done in November 2010 and published March 2011, was done by a team of scientists from the University of Rochester and University of Colorado School of Medicine They did an experiment to attempt to repair trauma to the Central Nervous System of an adult rat by replacing the glial cells. When the glial cells were injected into the injury of the adult rat’s spinal cord, astrocytes were generated by exposing human glial precursor cells to bone morphogenetic protein (Bone morphogenetic protein is important because it is considered to create tissue architecture throughout the body). So, with the bone protein and human glial cells combined, they promoted significant recovery of conscious foot placement, axonal growth, and obvious increases in neuronal survival in the spinal cord laminae. On the other hand, human glial precursor cells and astrocytes generated from these cells by being in contact with ciliary neurotrophic factors, failed to promote neuronal survival and support of axonal growth at the spot of the injury.

One study done in Shanghai had two types of hippocampal neuronal cultures: In one culture, the neuron was grown from a layer of astrocytes and the other culture was not in contact with any astrocytes, but they were instead fed a Glial Conditioned Medium (GCM), which inhibits the rapid growth of cultured astrocytes in the brains of rats in most cases. In their results they were able to see that astrocytes had a direct role in Long-term potentiation with the mixed culture (which is the culture that was grown from a layer of astrocytes) but not in GCM cultures.

Recent studies have shown that astrocytes play an important function in the regulation of neural stem cells. Research from the Schepens Eye Research Institute at Harvard shows the human brain to abound in neural stem cells, which are kept in a dormant state by chemical signals (ephrin-A2 and ephrin-A3) from the astrocytes. The astrocytes are able to activate the stem cells to transform into working neurons by dampening the release of ephrin-A2 and ephrin-A3.

Furthermore, studies are underway to determine whether astroglia play an instrumental role in depression, based on the link between diabetes and depression. Altered CNS glucose metabolism is seen in both these conditions, and the astroglial cells are the only cells with insulin receptors in the brain.

In a study published in a 2011 issue of Nature Biotechnology and reported in lay science article, a group of researchers from the University of Wisconsin reports that it has been able to direct embryonic and induced human stem cells to become astrocytes.

A 2012 study of the effects of marijuana on short term memories found that THC activates CB1 receptors of astrocytes which cause receptors for AMPA to be removed from the membranes of associated neurons.