The microenvironment following oxygen glucose deprivation/re-oxygenation-induced BSCB damage in vitro

• Published in: Brain research bulletin Vol. 143; pp. 171 - 180
• Main Authors: Cai, Xiao-Jun, Zhao, Jing-Jing, Lu, Yi, Zhang, Jian-Ping, Ren, Bing-Yan, Cao, Ting-Ting, Xi, Guang-Jun, Li, Zai-Wang
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.10.2018
• Subjects: Blood-spinal cord barrier; Oxygen glucose deprivation; Proinflammatory factors; Re-oxygenation; Tight junction proteins; Transepithelial electrical resistance; Blood-spinal cord barrier; Oxygen glucose deprivation; Transepithelial electrical resistance; Tight junction proteins; Proinflammatory factors; Re-oxygenation
• ISSN: 0361-9230; 1873-2747
• DOI: 10.1016/j.brainresbull.2018.08.005

•The inflammatory mediators were increased after BSCB damage induced by OGD/R.•Tight junction proteins deteriorate persistently after BSCB damage induced by OGD/R.•BSCB permeability increases longitudinally after BSCB damage induced by OGD/R.•BSCB secondary damage and inflammation injury after OGD/R have a close relationship. To characterize the microenvironment following blood-spinal cord barrier (BSCB) damage and to evaluate the role of BSCB disruption in secondary damage of spinal cord injury (SCI). A model of BSCB damage was established by co-culture of primary microvascular endothelial cells and glial cells obtained from rat spinal cord tissue followed by oxygen glucose deprivation/re-oxygenation (OGD/R). Permeability was evaluated by measuring the transendothelial electrical resistance (TEER) and the leakage test of Fluorescein isothiocyanate-dextran (FITC-dextran). The expression of tight junction (TJ) proteins (occludin and zonula occludens-1 (ZO-1) were evaluated by Western blot and immunofluorescence microscopy. Proinflammatory factors (TNF-α, iNOS, COX-2 and IL-1β), leukocyte chemotactic factors (MIP-1α, MIP-1β) and leukocyte adhesion factors (ICAM-1, VCAM-1) were detected in the culture medium under different conditions by enzyme-linked immuno sorbent assay (ELISA). The model of BSCB damage induced by OGD/R was successfully constructed. The maximum BSCB permeability occurred 6–12 hours but not within the first 3 h after OGD/R-induced damage. Likewise, the most significant period of TJ protein loss was also detected 6–12 hours after induction. During the hyper-acute period (3 h) following OGD/R-induced damage of BSCB, leukocyte chemotactic factors and leukocyte adhesion factors were significantly increased in the BSCB model. Pro-inflammation factors (TNF-α, IL-1β, iNOS, COX-2), leukocyte chemotactic factors (MIP-1α, MIP-1β) and leukocyte adhesion factors (ICAM-1, VCAM-1) were also sharply produced during the acute period (3–6 hours) and maintained plateau levels 6–12 hours following OGD/R-induced damage, which overlapped with the period of BSCB permeability maximum. A negative linear correlation was observed between the abundance of proinflammatory factors and the expression of TJ proteins (ZO-1 and occludin) and transepithelial electrical resistance (TEER), and a positive linear correlation was found with transendothelial FITC-dextran. Secondary damage continues after primary BSCB damage induced by OGD/R, exhibiting close ties with inflammation injury.