CaMKII inhibition with KN93 attenuates endothelin and serotonin receptor-mediated vasoconstriction and prevents subarachnoid hemorrhage-induced deficits in sensorimotor function

Abstract

BackgroundIt has been suggested that transcriptional upregulation of cerebral artery contractile endothelin (ETB) and 5-hydroxytryptamine (5-HT1B) receptors play an important role in the development of late cerebral ischemia and increased vasoconstriction after subarachnoid hemorrhage (SAH). We tested the hypothesis that inhibition of calcium calmodulin-dependent protein kinase II (CaMKII) may reduce cerebral vasoconstriction mediated by endothelin and serotonin receptors and improve neurological outcome after experimental SAH.MethodsSAH was induced in adult rats by injection of 250 μL autologous blood into the basal cisterns. The CaMKII activity in cerebral vessels was studied by Western blot and immunohistochemistry. The vasomotor responses of middle cerebral and basilar arteries were measured in a sensitive myograph system. The functional outcome was examined by the rotating pole test 2 and 3 days after SAH.ResultsSAH induced a rapid early increase in phosphorylated CaMKII protein at 1 h that was attenuated by cisternal administration of the CaMKII inhibitor KN93 (0.501 μg/kg) 45 min prior and immediately after SAH as evaluated by Western blot. Application of KN93 at 1 h and every 12 h post-SAH significantly reduced vascular CaMKII immunoreactivity at 72 h. In addition, contractile responses of cerebral arteries to endothelin-1 (ET-1) and 5-hydroxycarboxamide (5-CT) were increased at this time-point. KN93 treatment significantly attenuated the contraction induced by ET-1 and 5-CT. Importantly, treatment with the CaMKII inhibitor prevented SAH-induced deficits in neurological function, as evaluated by the rotating pole test, and similar sensorimotor scores were seen in sham-operated animals.ConclusionsThe present study has shown that SAH is associated with increased contractile responses to ET-1 and 5-CT in cerebral arteries and enhanced early activation of CaMKII. Treatment with the CaMKII inhibitor KN93 attenuated the contractile responses and prevented impaired sensorimotor function after SAH.

Calcium/Calmodulin–Dependent Protein Kinase II in Cerebrovascular Diseases

“…However, the total CaMKII expression remained unchanged [ 126 ], implying that CaMKII might play a role in SAH-induced cerebral vasculopathy. In agreement with Benjamin’s study, Lars et al also observed a rapid activation of CaMKII at its autophosphorylation site T286 at 1 h post SAH in rat cerebral artery lysates, and the activated CaMKII reduced to sham-operated levels at 6 and 24 h post SAH [ 127 ]. They also observed an increased overall CaMKII protein expression at 72 h post SAH by immunohistochemistry in cerebral vascular smooth muscle cells.…”

Dihydrolipoic Acid Inhibits Lysosomal Rupture and NLRP3 Through Lysosome-Associated Membrane Protein-1/Calcium/Calmodulin-Dependent Protein Kinase II/TAK1 Pathways After Subarachnoid Hemorrhage in Rat

“…This result is consistent with a recent study showing that CaMKII inhibitor prevented impaired sensorimotor function after SAH. 31 Additionally, several studies have demonstrated that CaMKII regulates the activity of TAK1/JNK, which is a central molecule in multiple signaling pathways. 32–34 However, little is known about the exact downstream signaling cascade initiated by CaMKII/TAK1/JNK after SAH.…”

Wnt Pathway: An Emerging Player in Vascular and Traumatic Mediated Brain Injuries

“…Interestingly, CaMKII, which is another component of the non-canonical Wnt pathway, plays an important role in the regulation of intracellular Ca 2+ homeostasis VSMCs contraction and vascular inflammation (House et al, 2008). It has been shown that CaMKII phosphorylation increased 1 h after SAH in the cerebral arteries whereas CaMKII protein expression increased after 3 days within the same arteries (Edvinsson et al, 2014). CaMKIIα, which is one of the major isoforms of CaMKII, was shown to modulate the inflammatory response of microglial cells (Huang et al, 2015).…”

“…The recent findings are suggesting that CaMKII activity, another main component of the non-canonical pathway, might be implicated in artery contraction or vasospasm (House et al, 2008), associated to poor prognosis after hemorrhagic stroke. Indeed, CaMKII expression was reported to increase in the arteries after SAH (Edvinsson et al, 2014). The administration of KN93 attenuated the SAH-induced contractions mediated by endothelin-1 (ET1) and 5-hydroxytryptamine (5-HT), a contractile protein implicated in basilar and MCA arteries, and ameliorated the sensorimotor function of rodents after SAH (Edvinsson et al, 2014).…”

“…Indeed, CaMKII expression was reported to increase in the arteries after SAH (Edvinsson et al, 2014). The administration of KN93 attenuated the SAH-induced contractions mediated by endothelin-1 (ET1) and 5-hydroxytryptamine (5-HT), a contractile protein implicated in basilar and MCA arteries, and ameliorated the sensorimotor function of rodents after SAH (Edvinsson et al, 2014). Another report has demonstrated that CaMKII phosphorylation is highly expressed in neurons and microglia in the brain of rodents after SAH (Zhou et al, 2018).…”