Serum Levels of VEGF-A and Its Receptors in Patients in Different Phases of Hemorrhagic and Ischemic Strokes

Prognostic Significance of Plasma VEGFA and VEGFR2 in Acute Ischemic Stroke-a Prospective Cohort Study

Enhancement of vascular remodeling in affected brain tissue is a novel therapy for acute ischemic stroke (AIS). However, conclusions regarding angiogenesis after AIS remain ambiguous. Vascular endothelial growth factor A (VEGFA) and VEGF receptor 2 (VEGFR2) are potent regulators of angiogenesis and vascular permeability. We aimed to investigate the association between VEGFA/VEGFR2 expression in the acute stage of stroke and prognosis of patients with AIS. We enrolled 120 patients with AIS within 24 h of stroke onset and 26 healthy controls. Plasma levels of VEGFA and VEGFR2 were measured by enzyme-linked immunosorbent assay (ELISA). The primary endpoint was an unfavorable outcome defined as a modified Rankin Scale (mRS) score > 2 at 3 months after AIS. Univariate and multivariate logistic regression analyses were used to identify risk factors affecting prognosis. Plasma VEGFA and VEGFR2 were significantly higher in patients with AIS than in health controls, and also significantly higher in patients with unfavorable than those with favorable outcomes. Moreover, both VEGFA and VEGFR2 showed a significantly positive correlation with mRS at 3 months. Univariate and multivariate analyses showed VEGFA and VEGFR2 remained associated with unfavorable outcomes, and adding VEGFA and VEGFR2 to the clinical model significantly improved risk reclassification (continuous net reclassification improvement, 105.71%; integrated discrimination improvement, 23.45%). The new risk model curve exhibited a good fit with an area under the receiver operating characteristic curve (ROC) curve of 0.9166 (0.8658-0.9674). Plasma VEGFA and VEGFR2 are potential markers for predicting prognosis; thus these two plasma biomarkers may improve risk stratification in patients with AIS.

The impact of experimental diabetes on intracerebral haemorrhage. A preclinical study

Although diabetes mellitus negatively affects post-ischaemic stroke injury and recovery, its impact on intracerebral haemorrhage (ICH) remains uncertain. This study aimed to investigate the effect of experimental diabetes (ED) on ICH-induced injury and neurological impairment. Sprague-Dawley rats were induced with ED 2 weeks before ICH induction. Animals were randomly assigned to four groups: 1)Healthy; 2)ICH; 3)ED; 4)ED-ICH. ICH and ED-ICH groups showed similar functional assessment. The ED-ICH group exhibited significantly lower haemorrhage volume compared with the ICH group, except at 1 mo. The oedema/ICH volume ratio and cistern displacement ratio were significantly higher in the ED-ICH group. Vascular markers revealed greater expression of α-SMA in the ED groups (ED and ED-ICH) compared with ICH. Conversely, the ICH groups (ED-ICH and ICH) exhibited higher levels of VEGF compared to the healthy and ED groups. An assessment of myelin tract integrity showed an increase in fractional anisotropy in the ED and ED-ICH groups compared with ICH. The ED group showed higher cryomyelin expression than the ED-ICH and ICH groups. Additionally, the ED groups (ED and ED-ICH) displayed higher expression of MOG and Olig-2 than ICH. As for inflammation, MCP-1 levels were significantly lower in the ED-ICH groups compared with the ICH group. Notably, ED did not aggravate the neurological outcome; however, it results in greater ICH-related brain oedema, greater brain structure displacement and lower haemorrhage volume. ED influences the cerebral vascularisation with an increase in vascular thickness, limits the inflammatory response and attenuates the deleterious effect of ICH on white matter integrity.

The Janus face of HIF-1α in ischemic stroke and the possible associated pathways

Stroke is the most devastating disease, causing paralysis and eventually death. Many clinical and experimental trials have been done in search of a new safe and efficient medicine; nevertheless, scientists have yet to discover successful remedies that are also free of adverse effects. This is owing to the variability in intensity, localization, medication routes, and each patient's immune system reaction. HIF-1α represents the modern tool employed to treat stroke diseases due to its functions: downstream genes such as glucose metabolism, angiogenesis, erythropoiesis, and cell survival. Its role can be achieved via two downstream EPO and VEGF strongly related to apoptosis and antioxidant processes. Recently, scientists paid more attention to drugs dealing with the HIF-1 pathway. This review focuses on medicines used for ischemia treatment and their potential HIF-1α pathways. Furthermore, we discussed the interaction between HIF-1α and other biological pathways such as oxidative stress; however, a spotlight has been focused on certain potential signalling contributed to the HIF-1α pathway. HIF-1α is an essential regulator of oxygen balance within cells which affects and controls the expression of thousands of genes related to sustaining homeostasis as oxygen levels fluctuate. HIF-1α's role in ischemic stroke strongly depends on the duration and severity of brain damage after onset. HIF-1α remains difficult to investigate, particularly in ischemic stroke, due to alterations in the acute and chronic phases of the disease, as well as discrepancies between the penumbra and ischemic core. This review emphasizes these contrasts and analyzes the future of this intriguing and demanding field.

New Biosensor for Determination of Neuropilin-1 with Detection by Surface Plasmon Resonance Imaging

Neuropilin-1 is transmembrane protein with soluble isoforms. It plays a pivotal role in both physiological and pathological processes. NRP-1 is involved in the immune response, formation of neuronal circuits, angiogenesis, survival and migration of cells. The specific SPRI biosensor for the determination of neuropilin-1 was constructed using mouse monoclonal antibody that captures unbound NRP-1 form body fluids. The biosensor exhibits linearity of the analytical signal between 0.01 and 2.5 ng/mL, average precision value 4.7% and recovery between 97% and 104%. The detection limit is 0.011 ng/mL, and the limit of quantification is 0.038 ng/mL. The biosensor was validated by parallel determination of NRP-1 in serum and saliva samples using the ELISA test, with good agreement of the results.