Bioreactor Transient Exposure Activates Specific Neurotrophic Pathway in Cortical Neurons

Abstract

Altered gravity forces might influence neuroplasticity and can provoke changes in biochemical mechanisms. In this contest, neurotrophins have a pivotal role, particularly nerve growth factor (NGF) and brain derived neurotrophic factor (BDNF). A suspension of dissociated cortical cells from rat embryos was exposed to 24 h of microgravity before plating in normal adherent culture system. Expression and transductional signalling pathways of NGF and BDNF were assessed at the end of maturational process (8-10 days in vitro). Rotating wall vessel bioreactor (RWV) preexposition did not induce changes in NGF expression and its high affinity receptor TrkA. On the contrary both BDNF expression and its high affinity receptor TrkB were strongly up-regulated, inducing Erk-5, but not Erk-1/2 activation and, in turn, MEF2C over-expression and activation. According to our previous and present results, we postulate that relatively short microgravitational stimuli, applied to neural cells

Hypergravity Stimulation Enhances PC12 Neuron-Like Cell Differentiation

“…Concerning effects of microgravity on neuronal cells, it has been reported that 1 h exposure induced damages in rodent neurons, resulting in a diminished neurite network density and neurite size, and in the alteration of β 3-tubulin localization [ 36 ]. Alterations of the NGF and BDNF signaling pathways in cortical neurons were also found under simulated microgravity [ 39 ]. When PC12 cells were exposed to a middle-term duration (8 days) microgravity, a reduced neurite extension with respect to 1 g cultures was demonstrated as well [ 40 ].…”