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bioRxiv · 10.1101/2024.02.07.579396

Neurons enhance blood-brain barrier function via upregulating claudin-5 and VE-cadherin expression due to GDNF secretion

Yang, L.·Lin, Z.·Mu, R.·Wu, W.·Zhi, H.·Liu, X.·Yang, H.·Liu, L.
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Abstract

Blood-brain barrier (BBB) prevents neurotoxins from entering central nervous system. We aimed to establish and characterize an in vitro triple co-culture BBB model consisting of brain endothelial cells hCMEC/D3, astrocytoma U251 cells, and neuroblastoma SH-SY5Y cells. Co-culture of SH-SY5Y and U251 cells markedly enhanced claudin-5 and VE-cadherin expression in hCMEC/D3 cells, accompanied by increased transendothelial electrical resistance and decreased permeability. Conditioned medium (CM) from SH-SY5Y cells (S-CM), U251 cells (U-CM), and co-culture of SH-SY5Y and U251 cells (US-CM) also promoted claudin-5 and VE-cadherin expression. Glial cell line-derived neurotrophic factor (GDNF) levels in S-CM and US-CM were significantly higher than CMs from hCMEC/D3 and U-CM. Both GDNF and US-CM upregulated claudin-5 and VE-cadherin expression, which were attenuated by anti-GDNF antibody and GDNF signaling inhibitors. GDNF increased claudin-5 expression via the PI3K/AKT/FOXO1 and MAPK/ERK pathways. Meanwhile, GDNF promoted VE-cadherin expression by activating PI3K/AKT/ETS1 and MAPK/ERK/ETS1 signaling. The roles of GDNF in BBB integrity were validated using brain-specific Gdnf silencing mice. The developed triple co-culture BBB model was successfully applied to predict BBB permeability. In conclusion, neurons enhance BBB integrity by upregulating claudin-5 and VE-cadherin expression through GDNF secretion and established triple co-culture BBB model may be used to predict drugs BBB permeability. Impact StatementNeurons and astrocytes enhance the integrity of BBB by releasing GDNF. The released GDNF upregulated claudin-5 and VE-cadherin expression by the activation of PI3K/AKT and MAPK/ERK pathways.

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Yang, L., Lin, Z., Mu, R., Wu, W., Zhi, H., Liu, X., Yang, H., Liu, L.. 2024-02-09. Neurons enhance blood-brain barrier function via upregulating claudin-5 and VE-cadherin expression due to GDNF secretion. https://doi.org/10.1101/2024.02.07.579396

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