Malvidin's effects on blood brain barrier alterations during hypoperfusion/ reperfusion injury

The present study was to aimed to assess the role of metalloproteinase-9 (MMP-9) in cerebral microvascular injury induced by 30 min bilateral common carotid attery occlusion (BCCAO) and 60 min reperfusion, and to evaluate malvidin1s protective effects on blood brain barrier (BBB) integrity. Rat pial microcirculation was visualized by fluorescence microscopy. MMP- 9 activity and expression were measured by zimography and western blot, respectively. Neuronal damage was evaluated using TTC staining and reactive oxygen species (ROS) formation was determine d by 2'-7' dichlorofluorescein diacetate assay. -. · BCCAO caused a progressive decrease in arteriolar diameter with an increase in microvascular leakage and leukocyte adhesion. Capillar y perfusion and red. . blood cell velocity (VRBC) were reduced . Moreover, zimography and western blot analysis revealed an increase in MMP-9 .activity and expression. These results were accompanied by marked neuronal damage and pronounced ROS production. Malvidin. administration induced a dose-related arteriolar dilation, reducing mtcrova scular leakage as well as leukocyte·adhesion. Capillary perfusion and VRBc were protected. Zimography and western blot analysis indicated a significant reduction in MMP-9 activity and expression . Finally, neuronal loss was prevented and there was no signifìcant increase in ROS · generation. In conclusion, malvidin appears to prevent rat pial rnicrodrculation changes due to hypoperfusion/reperfusion, preserving BBB integrity.