EN
Brain infl ammation contributes to the propagation of neuropathological events that involves activation of astrocytes and microglia. It remains obscure how activated glial cells affect the survival and differentiation of neural stem cells (NSC). The aim of the study was to analyze neuronal commitment of Human Umbilical Cord Blood derived Neural Stem Cells (HUCB-NSC) cultured in the presence of normal and LPS- or TMT-activated glial cells. Methods: HUCB-NSC (5 × 104/cm2 ) were co-cultured with normal or LPS (0.1 μg/ ml) and TMT (1μM)-stimulated astrocytes and microglial cells isolated from neonatal rat brain for proliferation and cell phenotype assessment. Pro-infl ammatory cytokines were estimated (ELISA). Results: Normal rat astrocytes induce HUCB-NSC to differentiate mostly into neurones but microglia stimulate HUCB-NSC to differentiate into neurons as well as into astrocytes. LPS- and TMTinduced astrocytes diminish neurogenesis of HUCB-NSC and increase astrocyte differentiation in comparison to non-stimulated astrocytes. Microglia activation by LPS and TMT decreases HUCBNSC differentiation into neurons but enhances oligodendrogenesis compared to normal microglia. Stimulation of astrocytes and microglia by LPS and TMT declines HUCB-NSC proliferation cocultured with astrocytes or with microglia. The presence of IL-1β, IL-6, TNF-α and NO was observed in glia cell culture supernatants after LPS and TMT implementation. Conclusion: Activation of astrocytes and microglia induced by LPS and TMT attenuate pro-neural effect of non-stimulated (resting) glia and suppress proliferation of HUCB-NSC in vitro. The release of pro-infl ammatory cytokines and NO might be partly responsible for this effect. Supported by MSHE grant No 142/P01/2008/35