Growth Differentiation Factor 15 Expression in Astrocytes After Excitotoxic Lesion in the Mouse Hippocampus

ABSTRACT

Growth differentiation factor 15 (GDF15) is, a member of the transforming growth factor beta (TGF-beta) superfamily of proteins. Although GDF15 is well established as a potent neurotrophic factor for neurons, little is known about its role in glial cells under neuropathological conditions. We monitored GDF15 expression in astrocyte activation after a kainic acid (KA)-induced neurodegeneration in the ICR mice hippocampus. In control, GDF15 immunoreactivity (IR) was evident in the neuronal layer of the hippocampus; however, GDF15 expression had increased in activated astrocytes throughout the hippocampal region at day 3 after the treatment with KA. LPS treatment in astrocytes dramatically increased GDF15 expression in primary astrocytes. In addition, LPS treatment resulted in the decrease of the IkappaB-alpha degradation and increase of the phosphorylation level of RelA/p65. These results indicate that GDF15 has a potential link to NF-kappaB activation, making GDF15 a valuable target for modulating inflammatory conditions.