NADPH oxidase mediates TNF-α-evoked in vitro brain barrier dysfunction: roles of apoptosis and time
The pro-inflammatory cytokine TNF-α severely perturbs the integrity of the blood–brain barrier (BBB). This study explored the specific roles of NADPH oxidase and associated downstream effectors by using human brain microvascular endothelial cells (HBMECs) and human astrocytes (HAs), the key componen...
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| Format: | Article |
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Elsevier
2014
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| Online Access: | https://eprints.nottingham.ac.uk/37978/ |
| _version_ | 1848795573426061312 |
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| author | Abdullah, Zuraidah Bayraktutan, Ulvi |
| author_facet | Abdullah, Zuraidah Bayraktutan, Ulvi |
| author_sort | Abdullah, Zuraidah |
| building | Nottingham Research Data Repository |
| collection | Online Access |
| description | The pro-inflammatory cytokine TNF-α severely perturbs the integrity of the blood–brain barrier (BBB). This study explored the specific roles of NADPH oxidase and associated downstream effectors by using human brain microvascular endothelial cells (HBMECs) and human astrocytes (HAs), the key components of BBB, alone or in co-cultures to mimic human BBB. Exposure to TNF-α (6 h) impaired BBB integrity as evidenced by marked decreases in transendothelial electrical resistance and concurrent increases in paracellular flux which appeared to subside with time (24 h). Increased barrier dysfunction concurred with increases in endothelial NADPH oxidase activity, O2radical dot− production, actin stress fibre formation, MMP-2/9 activities and concomitant decreases in antioxidant (CuZn-SOD and catalase) and tight junction (claudin-5 and occludin) protein expressions. Conversely, TNF-α did not affect astrocytic MMP activities and antioxidant enzyme expressions. Unlike BBB damage, rates of HBMEC and HA apoptosis increased by time. Suppression of NADPH oxidase by apocynin or diphenyleneiodonium prevented TNF-α-evoked morphological changes and apoptosis, attenuated endothelial MMP activity and helped retain usual tight junction protein expression and barrier function. In conclusion, HBMECs constitute the main source of oxidative stress and basement-membrane degrading endopeptidases in inflammatory conditions associated with excessive release of TNF-α where targeting NADPH oxidase may prove extremely beneficial in maintaining proper barrier activity through prevention of cytoskeletal and tight junction reorganisations. |
| first_indexed | 2025-11-14T19:34:14Z |
| format | Article |
| id | nottingham-37978 |
| institution | University of Nottingham Malaysia Campus |
| institution_category | Local University |
| last_indexed | 2025-11-14T19:34:14Z |
| publishDate | 2014 |
| publisher | Elsevier |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | nottingham-379782020-05-04T20:13:50Z https://eprints.nottingham.ac.uk/37978/ NADPH oxidase mediates TNF-α-evoked in vitro brain barrier dysfunction: roles of apoptosis and time Abdullah, Zuraidah Bayraktutan, Ulvi The pro-inflammatory cytokine TNF-α severely perturbs the integrity of the blood–brain barrier (BBB). This study explored the specific roles of NADPH oxidase and associated downstream effectors by using human brain microvascular endothelial cells (HBMECs) and human astrocytes (HAs), the key components of BBB, alone or in co-cultures to mimic human BBB. Exposure to TNF-α (6 h) impaired BBB integrity as evidenced by marked decreases in transendothelial electrical resistance and concurrent increases in paracellular flux which appeared to subside with time (24 h). Increased barrier dysfunction concurred with increases in endothelial NADPH oxidase activity, O2radical dot− production, actin stress fibre formation, MMP-2/9 activities and concomitant decreases in antioxidant (CuZn-SOD and catalase) and tight junction (claudin-5 and occludin) protein expressions. Conversely, TNF-α did not affect astrocytic MMP activities and antioxidant enzyme expressions. Unlike BBB damage, rates of HBMEC and HA apoptosis increased by time. Suppression of NADPH oxidase by apocynin or diphenyleneiodonium prevented TNF-α-evoked morphological changes and apoptosis, attenuated endothelial MMP activity and helped retain usual tight junction protein expression and barrier function. In conclusion, HBMECs constitute the main source of oxidative stress and basement-membrane degrading endopeptidases in inflammatory conditions associated with excessive release of TNF-α where targeting NADPH oxidase may prove extremely beneficial in maintaining proper barrier activity through prevention of cytoskeletal and tight junction reorganisations. Elsevier 2014-07 Article PeerReviewed Abdullah, Zuraidah and Bayraktutan, Ulvi (2014) NADPH oxidase mediates TNF-α-evoked in vitro brain barrier dysfunction: roles of apoptosis and time. Molecular and Cellular Neuroscience, 61 . pp. 72-84. ISSN 1044-7431 TNF-α; Blood–brain barrier; NADPH oxidase; MMP; Cytoskeleton http://www.sciencedirect.com/science/article/pii/S1044743114000633 doi:10.1016/j.mcn.2014.06.002 doi:10.1016/j.mcn.2014.06.002 |
| spellingShingle | TNF-α; Blood–brain barrier; NADPH oxidase; MMP; Cytoskeleton Abdullah, Zuraidah Bayraktutan, Ulvi NADPH oxidase mediates TNF-α-evoked in vitro brain barrier dysfunction: roles of apoptosis and time |
| title | NADPH oxidase mediates TNF-α-evoked in vitro brain barrier dysfunction: roles of apoptosis and time |
| title_full | NADPH oxidase mediates TNF-α-evoked in vitro brain barrier dysfunction: roles of apoptosis and time |
| title_fullStr | NADPH oxidase mediates TNF-α-evoked in vitro brain barrier dysfunction: roles of apoptosis and time |
| title_full_unstemmed | NADPH oxidase mediates TNF-α-evoked in vitro brain barrier dysfunction: roles of apoptosis and time |
| title_short | NADPH oxidase mediates TNF-α-evoked in vitro brain barrier dysfunction: roles of apoptosis and time |
| title_sort | nadph oxidase mediates tnf-α-evoked in vitro brain barrier dysfunction: roles of apoptosis and time |
| topic | TNF-α; Blood–brain barrier; NADPH oxidase; MMP; Cytoskeleton |
| url | https://eprints.nottingham.ac.uk/37978/ https://eprints.nottingham.ac.uk/37978/ https://eprints.nottingham.ac.uk/37978/ |