Blood-brain barrier disruption in diabetic mice is linked to Nrf2 signaling deficits: Role of ABCB10?. (13th July 2017)

• Record Type: Journal Article
• Authors: Sajja, Ravi K.; Prasad, Shikha; Tang, Suni; Kaisar, Mohammad A.; Cucullo, Luca
• Is Part Of: Neuroscience letters. Volume 653(2017)
• Page Start: 152
• Page End: 158
• Publication Date: 2017-07-13
• Subjects: ABCB10 -- db/db mice -- In vivo imaging -- Leukocyte -- Mitochondria -- Oxidative stress; Neurology -- Periodicals; Neurology -- Periodicals; Research -- Periodicals; Neurologie -- Périodiques; Neuroanatomie -- Périodiques; Neuropharmacologie -- Périodiques; Neurophysiologie -- Périodiques; Neurology; Periodicals; Electronic journals; 617.48
• DOI: 10.1016/j.neulet.2017.05.059
• Languages: English
• ISSNs: 0304-3940

Abstract

Highlights: In vivo fluorescence imaging revealed BBB hyper-permeability in diabetic mice. Nrf2 is significantly down-regulated in diabetic brain. Nrf2 regulates mitochondrial ABCB10 expression in human BBB endothelium. Hyperglycemia markedly reduces ABCB10 expression in BBB endothelial cells. Nrf2 or ABCB10 gene silencing increases BBB endothelial-monocyte adhesion. Abstract: Blood-brain barrier (BBB) damage is a critical neurovascular complication of diabetes mellitus that adversely affects the CNS health and function. Previously, we showed the protective role of NF-E2 related factor-2 (Nrf2), a redox sensitive transcription factor, in regulation of BBB integrity. Given the pathogenic role of mitochondrial oxidative stress in diabetes-related microvascular complications, we focused on assessing: 1) the impact of diabetes on brain Nrf2 in correlation with BBB permeability and 2) Nrf2-dependent regulation of the mitochondrial transporter ABCB10, an essential player in mitochondrial function and redox balance at BBB endothelium. Using live animal fluorescence imaging, we demonstrated a strong increase in BBB permeability to 70 kDa dextran in db/db diabetic mice that correlated with significant down-regulation of brain Nrf2 protein. Further, Nrf2 gene silencing in human BBB endothelial cells markedly suppressed ABCB10 protein, while Nrf2 activation by sulforaphane up-regulated ABCB10 expression. Interestingly, ABCB10 knockdown resulted in a strong-induction of Nrf2 driven anti-oxidant responses as evidenced by increased expression of Nrf2 and its downstream targets. Nrf2 or ABCB10 silencing elevated endothelial-monocyte adhesion suggesting an activated inflammatory cascade. Thus, our results demonstrate a novel mechanism of ABCB10 regulation driven by Nrf2. In summary, Nrf2 dysregulation and ABCB10 suppression could likely mediate endothelial oxidative/inflammatory stress and BBB disruption in diabetic subjects.