The role of astrocytes at the blood-brain-barrier (BBB), a functional interface between the brain and the body
A collaborative investigation led by the laboratory of Ignacio Torres Aleman helps explain the role of astrocytes at the blood-brain-barrier (BBB), a functional interface between the brain and the body.
Upon activation, neurons require extra energy (glucose) and oxygen supply. This requirement is satisfied through a process dubbed “neurovascular coupling”, whereby active neurons obtain nutrients and oxygen on demand.
Acting through astrocytes, insulin, a hormone involved in energy allocation throughout the body, modulates the formation of new brain vessels and brain glucose capture, assuring in this way proper coupling between glucose needs and blood supply. Disturbed insulin signaling onto astrocytes uncouples brain glucose uptake with brain blood flow due to excess oxidative stress at astrocyte mitochondria. Pharmacological amelioration of oxidative stress restores neurovascular coupling. Since many brain maladies present altered glucose handling and/or brain blood flow, insulin receptors in astrocytes may constitute a new therapeutic target for these diseases.