Neuronal membrane bioreactor as a tool for testing crocin neuroprotective effect in Alzheimer's disease

In this paper a neuronal membrane bioreactor was developed as platform for the in vitro reconstruction of a neuronal network with defined functional, geometric and neuroanatomical features. The bioreactor consists of modified polyacrylonitrile hollow fiber membranes that were assembled in parallel in order to establish two separate compartments: an intraluminal compartment within the fibers, in which the medium flowed, and an extraluminal compartment or shell outside of the fibers where cells were cultured. We explored the ability of the membrane bioreactor to promote the growth and functional differentiation of neuronal cells up to 2 weeks. Neuronal cells in the bioreactor covered completely the fiber surface and exhibited a high density of the axonal network reaching a very complex 3D structural organization characterized by the expression of presynaptic vesicle protein synaptophysin. Cells were also functionally active as demonstrated by the oxygen uptake rate and glucose consumption that increased with culture time achieving values of 17.7 nmol/min and 879 ± 113 nmol/min at day 15, respectively. The neuronal membrane bioreactor was used as in vitro model of A?-induced toxicity associated to Alzheimer's disease to test for the first time in cells the neuroprotective effect of crocin. The administration of the A? produced a dramatic decrease of cell viability and induced the reactive oxidative species (ROS) generation and apoptosis. When A?-peptide was administered together with crocin a significant dose-dependent inhibition of apoptosis and ROS production was observed pointing out the capability of crocin to prevent the aggregation of A? peptide and subsequent neurotoxicity associated to Alzheimer's disease.