Migraine and neuroinflammation: the inflammasome perspective

Abstract Background Neuroinflammation has an important role in the pathophysiology of migraine, which is a complex neuro-glio-vascular disorder. The main aim of this review is to highlight findings of cortical spreading depolarization (CSD)-induced neuroinflammatory signaling in brain parenchyma from the inflammasome perspective. In addition, we discuss the limited data of the contribution of inflammasomes to other aspects of migraine pathophysiology, foremost the activation of the trigeminovascular system and thereby the generation of migraine pain. Main body Inflammasomes are signaling multiprotein complexes and key components of the innate immune system. Their activation causes the production of inflammatory cytokines that can stimulate trigeminal neurons and are thus relevant to the generation of migraine pain. The contribution of inflammasome activation to pain signaling has attracted considerable attention in recent years. Nucleotide-binding domain (NOD)-like receptor family pyrin domain containing 3 (NLRP3) is the best characterized inflammasome and there is emerging evidence of its role in a variety of inflammatory pain conditions, including migraine. In this review, we discuss, from an inflammasome point of view, cortical spreading depolarization (CSD)-induced neuroinflammatory signaling in brain parenchyma, the connection with genetic factors that make the brain vulnerable to CSD, and the relation of the inflammasome with diseases that are co-morbid with migraine, including stroke, epilepsy, and the possible links with COVID-19 infection. Conclusion Neuroinflammatory pathways, specifically those involving inflammasome proteins, seem promising candidates as treatment targets, and perhaps even biomarkers, in migraine

Vegf Protects Brain Against Focal Ischemia Without Increasing Blood-Brain Permeability When Administered Intracerebroventricularly

Delayed administration of vascular endothelial growth factor (VEGF) promotes functional recovery after focal cerebral ischemia. However, early intravenous injection of VEGF increases blood-brain barrier (BBB) leakage, hemorrhagic transformation and infarct volume whereas its application to cortical surface is neuroprotective. We have investigated whether or not early intracerebroventricular administration of VEGF could replicate the neuroprotective effect observed with topical application and the mechanism of action of this protection. Mice were subjected to 90 mins middle cerebral artery (MCA) occlusion and 24h of reperfusion. Vascular endothelial growth factor (8ng, intracerebroventricular) was administered 1 or 3h after reperfusion. Compared with the vehicle-treated (intracerebroventricular) group, VEGF decreased the infarct volume along with BBB leakage in both treatment groups. Neurologic disability scores improved in parallel to the changes in infarct volume. Independently of the decrease in infarct size, VEGF also reduced the number of TUNEL-positive apoptotic neurons. Phospo-Akt levels were significantly higher in ischemic hemispheres of the VEGF-treated mice. Contrary to intracerebroventricular route, intravenous administration of VEGF (15 mu g/kg) enhanced the infarct volume as previously reported for the rat. In conclusion, single intracerebroventricular injection of VEGF protects brain against ischemia without adversely affecting 131313 permeability, and has a relatively long therapeutic time window. This early neuroprotective action, observed well before recovery-promoting actions such as angiogenesis, possibly involves activation of the PI-3-Akt pathway.WoSScopu

Development and brain delivery of chitosan-PEG nanoparticles functionalized with the monoclonal antibody OX26

The inhibition of the caspase-3 enzyme is reported to increase neuronal cell survival following cerebral ischemia. The peptide Z-DEVD-FMK is a specific caspase inhibitor, which significantly reduces vulnerability to the neuronal cell death. However, this molecule is unable to cross the blood-brain barrier (BBB) and to diffuse into the brain tissue. Thus, the development of an effective delivery system is needed to provide sufficient drug concentration into the brain to prevent cell death. Using the avidin (SA)-biotin (BIO) technology, we describe here the design of chitosan (CS) nanospheres conjugated with poly(ethylene glycol) (PEG) bearing the OX26 monoclonal antibody whose affinity for the transferrin receptor (TfR) may trigger receptor-mediated transport across the BBB. These functionalized CS-PEG-BIO-SA/OX26 nanoparticles (NPs) were characterized for their particle size, zeta potential, drug loading capacity, and release properties. Fluorescently labeled CS-PEG-BIO-SA/OX26 nanoparticles were administered systemically to mice in order to evaluate their efficacy for brain translocation. The results showed that an important amount of nanoparticles were located in the brain, outside of the intravascular compartment. These findings, which were also confirmed by electron microscopic examination of the brain tissue indicate that this novel targeted nanoparticulate drug delivery system was able to translocate into the brain tissue after iv administration. Consequently, these novel nanoparticles are promising carriers for the transport of the anticaspase peptide Z-DEVD-FMK into the brain