Background: Aneurysmal subarachnoid hemorrhage (aSAH) is still a fatal and morbid disease, although bleeding aneurysms can be secured in almost all cases. Occurrence of post-SAH complications including cerebral vasospasm, delayed cerebral ischemia, hydrocephalus, epilepsy, and infections are the main determinants of clinical outcome. Hence, it is important to search for early predictors for specific post-SAH complications to treat these complications properly. Both cellular and molecular (cytokines) inflammation play a key role after aSAH during the phase of occurrence of post-SAH complications. Interleukin-6 (IL-6) is a well-known cytokine that has been extensively analyzed in cerebrospinal fluid (CSF) of patients after aSAH, but detailed studies exploring the role of systemic IL-6 in aSAH associated complications and its impact on early clinical outcome prediction are lacking. The current study aims to analyze the systemic IL-6 levels over two weeks after bleeding and its role in post-SAH complications. Methods: We recruited 80 aSAH patients prospectively who underwent peripheral venous blood withdrawal in serum gel tubes. The blood was centrifuged to harvest the serum, which was immediately frozen at −80 °C until analysis. Serum IL-6 levels were quantified using Immulite immunoassay system. Patient records including age, gender, post-SAH complications, aneurysm treatment, and clinical outcome (modified Rankin scale and Glasgow outcome scale) were retrieved to allow different subgroup analysis. Results: Serum IL-6 levels were significantly raised after aSAH compared to healthy controls over the first two weeks after hemorrhage. Serum IL-6 levels were found to be significantly elevated in aSAH patients presenting with higher Hunt and Hess grades, increasing age, and both intraventricular and intracerebral hemorrhage. Interestingly, serum IL-6 was also significantly raised in aSAH patients who developed seizures, cerebral vasospasm (CVS), and chronic hydrocephalus. IL-6 levels were sensitive to the development of infections and showed an increase in patients who developed pneumoniae. Intriguingly, we found a delayed increase in serum IL-6 in patients developing cerebral infarction. Finally, IL-6 levels were significantly higher in patients presenting with poor clinical outcome in comparison to good clinical outcome at discharge from hospital. Conclusion: Serum IL-6 levels were elevated early after aSAH and remained high over the two weeks after initial bleeding. Serum IL-6 was elevated in different aSAH associated complications, acting as a non-specific marker for post-SAH complications and an important biomarker for clinical outcome at discharge.

No abstract

Aneurysmal subarachnoid hemorrhage (aSAH) represents only a small portion of all strokes, but accounts for almost half of the deaths caused by stroke worldwide. Neurosurgical clipping and endovascular coiling can successfully obliterate the bleeding aneurysms, but ensuing complications such as cerebral vasospasm, acute and chronic hydrocephalus, seizures, cortical spreading depression, delayed ischemic neurological deficits, and delayed cerebral ischemia lead to poor clinical outcomes. The mechanisms leading to these complications are complex and poorly understood. Early brain injury resulting from transient global ischemia can release molecules that may be critical to initiate and sustain inflammatory response. Hence, the events during early brain injury can influence the occurrence of delayed brain injury. Since the damage associated molecular pattern molecules (DAMPs) might be the initiators of inflammation in the pathophysiology of aSAH, so the aim of this review is to highlight their role in the context of aSAH from diagnostic, prognostic, therapeutic, and drug therapy monitoring perspectives. DAMPs represent a diverse and a heterogenous group of molecules derived from different compartments of cells upon injury. Here, we have reviewed the most important DAMPs molecules including high mobility group box-1 (HMGB1), S100B, hemoglobin and its derivatives, extracellular matrix components, IL-1α, IL-33, and mitochondrial DNA in the context of aSAH and their role in post-aSAH complications and clinical outcome after aSAH.

No abstract

Aneurysmal subarachnoid hemorrhage (aSAH) is a highly fatal and morbid type of hemorrhagic strokes. Intracranial aneurysms (ICAs) rupture cause subarachnoid hemorrhage. ICAs formation, growth and rupture involves cellular and molecular inflammation. Macrophages orchestrate inflammation in the wall of ICAs. Macrophages generally polarize either into classical inflammatory (M1) or alternatively-activated anti-inflammatory (M2)-phenotype. Macrophage infiltration and polarization toward M1-phenotype increases the risk of aneurysm rupture. Strategies that deplete, inhibit infiltration, ameliorate macrophage inflammation or polarize to M2-type protect against ICAs rupture. However, clinical translational data is still lacking. This review summarizes the contribution of macrophage led inflammation in the aneurysm wall and discuss pharmacological strategies to modulate the macrophageal response during ICAs formation and rupture.

No abstract

Objective: To assay peripheral inter-ictal cytokine serum levels and possible relations with non-invasive vagus nerve stimulation (nVNS) responsiveness in migraineurs. Methods: This double-blinded, sham-controlled study enrolled 48 subjects and measured headache severity, frequency [headache days/month, number of total and mild/moderate/severe classified attacks/ month], functional state [sleep, mood, body weight, migraine-associated disability] and serum levels of inflammatory markers [inter-ictal] using enzyme-linked immunoassays at baseline and after 2 months of adjunctive nVNS compared to sham stimulation and suitably matched controls. Results: No significant differences were observed at baseline and after 2 months for headache severity, total attacks/month, headache days/month and functional outcome [sleep, mood, disability] between verum and sham nVNS. However, the number of severe attacks/month significantly decreased in the verum nVNS group and circulating pro-inflammatory IL-1b was elevated significantly in the sham group compared to nVNS. Levels of anti-inflammatory IL-10 were significantly higher at baseline in both groups compared to healthy controls, but not at 2 months follow-up [p < 0.05]. Concentrations of high-mobility group box-1 (HMGB-1), IL-6, tumor-necrosis factor-a (TNF-a), leptin, adiponectin, ghrelin remained unchanged [p > 0.05]. No severe device-/stimulation-related adverse events occurred. Conclusion: 2 months of adjunctive cervical nVNS significantly declined the number of severe attacks/ month. Pro-inflammatory IL-1b plasma levels [inter-ictal] were higher in sham-treated migraine patients compared to verum nVNS. However, pro-[IL-6, HMGB-1, TNF-a, leptin] and anti-inflammatory [IL-10, adiponectin, ghrelin] mediators did not differ statistically. Profiling of neuroinflammatory circuits in migraine to predict nVNS responsiveness remains an experimental approach, which may be biased by pre-analytic variables warranting large-scale biobank-based systematic investigations [omics].

Background: Rising evidence indicate that oxytocin and IL-1β impact trigemino-nociceptive signaling. Current perspectives on migraine physiopathology emphasize a cytokine bias towards a pro-inflammatory status. The antinociceptive impact of oxytocin has been reported in preclinical and human trials. Cervical non-invasive vagus nerve stimulation (nVNS) emerges as an add-on treatment for the preventive and abortive use in migraine. Less is known about its potential to modulate saliva inflammatory signaling in migraine patients. The rationale was to perform inter-ictal saliva measures of oxytocin and IL-1ß along with headache assessment in migraine patients with 10 weeks adjunctive nVNS compared to healthy controls.Methods: 12 migraineurs and 12 suitably matched healthy control were studied with inter-ictal saliva assay of proand anti-neuroinflammatory cytokines using enzyme-linked immuno assay techniques along with assessment of headache severity/frequency and associated functional capacity at baseline and after 10 weeks adjunctive cervical nVNS.Results: nVNS significantly reduced headache severity (VAS), frequency (headache days and total number of attacks) and significantly improved sleep quality compared to baseline (p < 0.01). Inter-ictal saliva oxytocin and IL-1β were significantly elevated pre-as well as post-nVNS compared to healthy controls (p < 0.01) and similarly showed changes that may reflect the observed clinical effects. Conclusions:Our results add to accumulating evidence for a therapeutic efficacy of adjunct cervical non-invasive vagus nerve stimulation in migraine patients. This study failed to provide an evidence-derived conclusion addressed to the predictive value and usefulness of saliva assays due to its uncontrolled study design. However, saliva screening of mediators associated with trigemino-nociceptive traffic represents a novel approach, thus deserve future targeted headache research.