Alpha-tocopherol Prevents H2O2-induced Tight Junction Occludin Disruption in Blood-Brain Barrier / 체질인류학회지

ABSTRACT

Vitamin E is the most important lipid-soluble antioxidant in humans. Although alpha-tocopherol is suggested that it has protective effect from many diseases, little is known about the prevention of occludin alteration in tight junction of blood-brain barrier (BBB) under pathologic insults producing reactive oxygen species (ROSs). In this study, the effects of alpha-tocopherol on H2O2-induced tight junction occludin were studied. Primary culture of rat brain microvessel endothelial cells was investigated with confocal microscopy, Western blot, and cell viability assay. Alpha-tocopherol had no apparent cytotoxicity up to 2.8 mM. The preincubation with alpha-tocopherol suppressed the H2O2-induced cytotoxicity in Alamar Blue assay and phase contrast microscopy. In confocal laser microscopy and Western blot, H2O2-induced loss of occludin was suppressed by preincubation with alpha-tocopherol. The present findings provide evidence that alpha-tocopherol may be beneficial for cellular protection from pathologic insults. Since alpha-tocopherol was demonstrated to have far fewer adverse effects, it would become a noteworthy nutrient or drug for the treatment of neurodegenerative diseases.