The protective effect of HET0016 on brain edema and blood–brain barrier dysfunction after cerebral ischemia/reperfusion

• Published in: Brain research 2014-01, Vol.1544, p.45-53
• Main Authors: Liu, Yu, Wang, Di, Wang, Huan, Qu, Youyang, Xiao, Xingjun, Zhu, Yulan
• Format: Article
• Language: English
• Subjects: 20-hydroxyeicosatetraenoic acid; Amidines - therapeutic use; Animals; Biological and medical sciences; Blood-Brain Barrier - drug effects; Blood-Brain Barrier - ultrastructure; Blood–brain barrier disruption; Brain Edema - drug therapy; Brain Ischemia - drug therapy; Cerebral ischemia/reperfusion; Claudin-5 - drug effects; Claudin-5 - metabolism; Headache. Facial pains. Syncopes. Epilepsia. Intracranial hypertension. Brain oedema. Cerebral palsy; HET0016; JNK; Male; MAP Kinase Signaling System - drug effects; Matrix Metalloproteinase 9 - drug effects; Medical sciences; Nervous system (semeiology, syndromes); Neurology; Neuroprotective Agents - therapeutic use; Rats; Rats, Sprague-Dawley; Reperfusion Injury - drug therapy; Vascular diseases and vascular malformations of the nervous system; Zonula Occludens-1 Protein - drug effects; Zonula Occludens-1 Protein - metabolism
• ISSN: 0006-8993; 1872-6240
• DOI: 10.1016/j.brainres.2013.11.031

Abstract N-hydroxy-N-(4-butyl-2-methylphenyl) formamidine (HET0016) is a specific 20-hydroxyeicosatetraenoic acid (20-HETE) inhibitor which was first synthesized in 2001. It has been demonstrated that HET0016 reduces cerebral infarction volume in rat middle cerebral artery occlusion (MCAO) models. However, little is known about the role of HET0016 in the blood–brain barrier (BBB) dysfunction after cerebral ischemia/reperfusion (I/R) injury. The present study was designed to examine the effect of HET0016 in a MCAO and reperfusion rat model to determine whether it protects against brain edema and BBB disruption. Rats were subjected to 90 min MCAO, followed by 4, 24, 48, and 72 h reperfusion. Brain edema was measured according to the wet and dry weight method. BBB permeability based on the extravasation of Evans blue and sodium fluorescein was detected. BBB ultrastructure alterations were presented through transmission electron microscope. Superoxide production in ischemic tissue was also measured by dihydroethidium fluorescent probe. Western blot was used to analyze the expression of Claudin-5, ZO-1, MMP-9, and JNK pathway. At 24 h after reperfusion, HET0016 reduced brain edema and BBB leakage. Ultrastructural damage of BBB and the increase of superoxide production were attenuated by HET0016 treatment. Western blot showed that HET0016 suppressed the activation of MMP-9 and JNK pathway but restored the expression of Claudin-5 and ZO-1. In conclusion, these results suggest that HET0016 protects BBB dysfunction after I/R by regulating the expression of MMP-9 and tight junction proteins. Furthermore, inhibition of oxidative stress and JNK pathway may be involved in this protecting effect.