Glutamate excitotoxicity is a very important and fundamental process in neurodegeneration, said Fisher. Finding molecules, such as ceftriaxone, that may correct this problem can lead to preservation and increased survival of neurons in the brain and it may have direct implications in the therapy of many neurodegenerative diseases, such as in Alzheimers disease, stroke, ALS and epilepsy.
In this study, Fisher and his colleagues were interested in identifying how the promoter region of the EAAT2 gene controlled the expression of glutamate in a group of brain cells called astrocytes. Using molecular biological approaches, the team examined all the regions and sequences in the promoter region and systematically eliminated them to then define which region was necessary to respond to ceftriaxone.
According to Fisher, this led the team to a critical transcription factor called nuclear factor kappaB, NF- kappaB, which regulates many functions in the brain and other parts of the body. This is a central molecule involved in regulation of genes controlling cell growth and survival. Once they identified critical regions in the EAAT2 promoter that might regulate activity, they found that alteration of one specific NF-kappaB site by mutation in the promoter was responsible for up-regulation of EAAT2 expression and consequently glutamate transport by ceftriaxone.
This work not only has implications for the field of neurodegeneration and neurobiology, but may also help us more clearly understand brain cancer, including malignant glioma, an invariably fatal tumor, and how it impacts brain function, said Fisher, who is the first i
|Contact: Sathy Achia Abraham|
Virginia Commonwealth University