EFFECT OF NEUREGULIN ON RADIAL GLIAL CELLS DERIVED FROM RAT SPINAL CORD

Abstract

Radial glial cells have a crucial role in the developing brain and spinal cord during neurogenesis and after birth. They are involved in the support of migrating neurons and act as a progenitor population for astrocytes and neurons. Neuregulin is a glycoprotein, belonging to the family of the epidermal growth factor-like ligands. These growth factors are important for the development and functioning of the central nervous system. It has been demonstrated that neuregulin plays a critical role in the establishment, maintenance, and maturation of cerebral radial glial cells (Schmid et al 2003, Zheng et al 2006). Regarding to astrocytes, it has been found that neuregulin can induce the transformation of cerebellar astrocytes into a radial glia phenotype (Gierdalski et al 2005). In the present study we investigated the effect of exogenous neuregulin on glial cells in a mixed glial cell culture system. Mixed glial cell cultures were prepared from spinal cords of neonatal rat pups (P3) as described by Moreels et al (2006) and were treated with different concentrations of neuregulin (ranging from 1 ng/ml to 25 ng/ml). After 6-7 days, cell cultures were fixed and characterised using cell-specific immunocytochemical markers including GFAP, MBP, nestin and 3CB2. Treatment with different concentrations of neuregulin (1-10-25 ng/ml) increased the number of astrocytes in a dose-dependent manner. In contrast, the number of radial glial cells decreased after treatment. However, no morphological changes could be observed. In conclusion, neuregulin has an influence on both radial glial cells and astrocytes. Further research is needed to investigate whether neuregulin promotes the proliferation of astrocytes or the differentiation of radial glial cells into astrocytes.