Osteopontin in the Cerebrospinal Fluid of Patients with Severe Aneurysmal Subarachnoid Hemorrhage

Neural repair function of osteopontin in stroke and stroke‑related diseases (Review)

Stroke, including hemorrhagic stroke and ischemic stroke, is a common disease of the central nervous system. It is characterized by a high mortality and disability rate and is closely associated with atherosclerosis, hypertension hyperglycemia, atrial fibrillation and unhealthy living habits. The continuous development of surgery and medications has decreased the mortality rate of patients with stroke and has greatly improved the disease prognosis. At present, the direction of clinical treatment and research has gradually shifted to the repair of nerve function after stroke. Osteopontin (OPN) is a widely distributed extracellular matrix protein. Due to its structural characteristics, OPN can be cut and modified into terminal fragments with different functions, which play different roles in various pathophysiological processes, such as formation of tumors, inflammation and autoimmune diseases. It has also become a potential diagnostic and therapeutic marker. In order to comprehensively analyze the specific role of OPN in nerve repair and its relationship with stroke and stroke-related diseases, the following key words were used: 'Osteopontin, stroke, atherosis, neuroplasticity, neural repair'. PubMed, Web of Science and Cochrane articles related to OPN were searched and summarized. The present review describes the OPN structure, isoforms, functions and its neural repair mechanism, and its association with the occurrence and development of stroke and related diseases was explored.

Circulating Extracellular Vesicles in Subarachnoid Hemorrhage Patients: Characterization and Cellular Effects

Circulating extracellular vesicles (EVs) may play a pathophysiological role in the onset of complications of subarachnoid hemorrhage (SAH), potentially contributing to the development of vasospasm (VP). In this study, we aimed to characterize circulating EVs in SAH patients and examine their effects on endothelial and smooth muscle cells (SMCs). In a total of 18 SAH patients, 10 with VP (VP), 8 without VP (NVP), and 5 healthy controls (HC), clinical variables were recorded at different time points. EVs isolated from plasma samples were characterized and used to stimulate human vascular endothelial cells (HUVECs) and SMCs. We found that EVs from SAH patients expressed markers of T-lymphocytes and platelets and had a larger size and a higher concentration compared to those from HC. Moreover, EVs from VP patients reduced cell viability and mitochondrial membrane potential in HUVECs and increased oxidants and nitric oxide (NO) release. Furthermore, EVs from SAH patients increased intracellular calcium levels in SMCs. Altogether, our findings reveal an altered pattern of circulating EVs in SAH patients, suggesting their pathogenic role in promoting endothelial damage and enhancing smooth muscle reactivity. These results have significant implications for the use of EVs as potential diagnostic/prognostic markers and therapeutic tools in SAH management.

Biomarkers in aneurysmal subarachnoid hemorrhage: A short review

Poor outcomes of aneurysmal subarachnoid hemorrhage (aSAH) can be the result of the initial catastrophic event or the many acute or delayed neurological complications. Recent evidence suggests that some molecules play a critical role in both events, through some unknown pathways involved. Understanding the role of these molecules in these events could allow to improve diagnostic accuracy, guide management, and prevent long-term disability in aSAH. Here we present the studies on aSAH biomarkers present in current medical literature, highlighting their roles and main results.

Compartmental Cerebrospinal Fluid Events Occurring after Subarachnoid Hemorrhage: An "Heparin Oriented" Systematic Review

Subarachnoid hemorrhage (SAH) represents a severe acute event with high morbidity and mortality due to the development of early brain injury (EBI), secondary delayed cerebral ischemia (DCI), and shunt-related hydrocephalus. Secondary events (SSE) such as neuroinflammation, vasospasm, excitotoxicity, blood-brain barrier disruption, oxidative cascade, and neuronal apoptosis are related to DCI. Despite improvement in management strategies and therapeutic protocols, surviving patients frequently present neurological deficits with neurocognitive impairment. The aim of this paper is to offer to clinicians a practical review of the actually documented pathophysiological events following subarachnoid hemorrhage. To reach our goal we performed a literature review analyzing reported studies regarding the mediators involved in the pathophysiological events following SAH occurring in the cerebrospinal fluid (CSF) (hemoglobin degradation products, platelets, complement, cytokines, chemokines, leucocytes, endothelin-1, NO-synthase, osteopontin, matricellular proteins, blood-brain barrier disruption, microglia polarization). The cascade of pathophysiological events secondary to SAH is very complex and involves several interconnected, but also distinct pathways. The identification of single therapeutical targets or specific pharmacological agents may be a limited strategy able to block only selective pathophysiological paths, but not the global evolution of SAH-related events. We report furthermore on the role of heparin in SAH management and discuss the rationale for use of intrathecal heparin as a pleiotropic therapeutical agent. The combination of the anticoagulant effect and the ability to interfere with SSE theoretically make heparin a very interesting molecule for SAH management.

Higher Plasma Osteopontin Concentrations Associated with Subsequent Development of Chronic Shunt-Dependent Hydrocephalus After Aneurysmal Subarachnoid Hemorrhage

A matricellular protein osteopontin (OPN) is considered to exert neuroprotective and healing effects on neurovascular injuries in an acute phase of aneurysmal subarachnoid hemorrhage (SAH). However, the relationships between OPN expression and chronic shunt-dependent hydrocephalus (SDHC) have never been investigated. In 166 SAH patients (derivation and validation cohorts, 110 and 56, respectively), plasma OPN levels were serially measured at days1-3, 4-6, 7-9, and 10-12 after aneurysmal obliteration. The OPN levels and clinical factors were compared between patients with and without subsequent development of chronic SDHC. Plasma OPN levels in the SDHC patients increased from days 1-3 to days 4-6 and remained high thereafter, while those in the non-SDHC patients peaked at days 4-6 and then decreased over time. Plasma OPN levels had no correlation with serum levels of C-reactive protein (CRP), a systemic inflammatory marker. Univariate analyses showed that age, modified Fisher grade, acute hydrocephalus, cerebrospinal fluid drainage, and OPN and CRP levels at days 10-12 were significantly different between patients with and without SDHC. Multivariate analyses revealed that higher plasma OPN levels at days 10-12 were an independent factor associated with the development of SDHC, in addition to a more frequent use of cerebrospinal fluid drainage and higher modified Fisher grade at admission. Plasma OPN levels at days 10-12 maintained similar discrimination power in the validation cohort and had good calibration on the Hosmer-Lemeshow goodness-of-fit test. Prolonged higher expression of OPN may contribute to the development of post-SAH SDHC, possibly by excessive repairing effects promoting fibrosis in the subarachnoid space.

Efficacy and safety profile of neuroendoscopic hematoma evacuation combined with intraventricular lavage in severe intraventricular hemorrhage patients

OBJECTIVE

The present study was conducted to explore the effect of neuroendoscopic hematoma evacuation in severe intraventricular hemorrhage (IVH).

METHODS

Totally 81 patients with severe IVH in our hospital from November 2017 to March 2019 were divided into the intervention group (38 cases who received neuroendoscopic hematoma evacuation combined with intraventricular lavage) and the control group (40 cases who received trepanation drainage). The perioperative condition, hematoma clearance rate, Glasgow coma score (GCS), hematoma recurrence rate, and prognosis were observed and compared between the two groups after treatment.

RESULTS

The operative time, time of cerebrospinal fluid drainage, and intracranial infection rate in the intervention group elicited superior results to those in the control group (p < .05). The clearance rate of hematoma in the intervention group was higher than that in the control group at 6 hr, 1, 3, and 7 days postoperatively (p < .05). The postoperative 3- and 7-day GCS scores in the intervention group were higher than those in the control group, and the recurrence rate of hematoma in the intervention group was significantly lower than that in the control group (p < .05), and the good/excellent rate of ADL in the intervention group was significantly higher than that in the control group (p < .05).

CONCLUSION

Neuroendoscopic hematoma evacuation combined with intraventricular lavage showed evident beneficial outcomes in patients with severe IVH. It can effectively improve the perioperative condition and improve the hematoma clearance rate and is beneficial to the prognosis of patients with severe IVH.

Osteopontin as a candidate of therapeutic application for the acute brain injury

Acute brain injury is the leading cause of human death and disability worldwide, which includes intracerebral haemorrhage, subarachnoid haemorrhage, cerebral ischaemia, traumatic brain injury and hypoxia‐ischaemia brain injury. Currently, clinical treatments for neurological dysfunction of acute brain injury have not been satisfactory. Osteopontin (OPN) is a complex adhesion protein and cytokine that interacts with multiple receptors including integrins and CD44 variants, exhibiting mostly neuroprotective roles and showing therapeutic potential for acute brain injury. OPN‐induced tissue remodelling and functional repair mainly rely on its positive roles in the coordination of pro‐inflammatory and anti‐inflammatory responses, blood‐brain barrier maintenance and anti‐apoptotic actions, as well as other mechanisms such as affecting the chemotaxis and proliferation of nerve cells. The blood OPN strongly parallel with the OPN induced in the brain and can be used as a novel biomarker of the susceptibility, severity and outcome of acute brain injury. In the present review, we summarized the molecular signalling mechanisms of OPN as well as its overall role in different kinds of acute brain injury.