Current Neurovascular Research - Volume 18, Issue 1, 2021

Background: Coronavirus disease 2019 (COVID-19) has spread worldwide and poses a great threat to global health. COVID-19 has also an unneglected effect on migraine patients. Migraine attack frequency is one of the migraine characteristics, and its impact during COVID-19 needs further research. We aimed to evaluate whether migraine attack frequency during the COVID-19 pandemic differed from pre-COVID-19 attack frequency and explore possible influencing factors during the pandemic. Methods: This prospective cohort study enrolled 187 migraine patients from the Department of Neurology of West China Hospital from October 2019 to December 2019. After the inclusion and exclusion criteria, a total of 157 patients were included. We collected demographic data, clinical characteristics, and epidemiological contact information and followed up on March 2020. Then, paired-samples T-tests, logistic regression and interaction tests were used to analyze the data. Results: We found that the migraine attack frequency was 2.47 ± 1.12 before and 3.54 ± 1.79 during COVID-19 (P<0.0001). Then, we divided patients into two groups based on the difference in migraine attack frequency between the COVID-19 and pre-COVID-19 periods and employed logistic regression analysis. In the logistic regression analysis, divorced status (OR = 6.53, P = 0.0453), good sleep pre-COVID-19 and poor sleep during COVID-19 (OR = 3.11, P = 0.0432) had independent effects on migraine attack frequency during the COVID-19 pandemic. We found no interaction in poor sleep during COVID-19 between various subgroups. Conclusion: We found that migraineurs’ headache attacks were more frequent during COVID-19 than pre-COVID-19 and that increased migraine attack frequency was independently related to divorced status and poor sleep during COVID-19.

Objective: Major Depressive Disorder (MDD) is a major health problem worldwide. Estrogen interacts with the central nervous system and has been shown to affect anxiety and depressive behavior. Estrogen mediates its effects by connecting its receptors, estrogen receptors 1 and 2. The purpose of this case-control study was to clarify the association between MDD risk and estrogen receptor 1 (ESR1) gene variants. Methods: This study included 245 individuals (125 MDD patients and 120 healthy controls). Polymerase Chain Reaction (PCR) and Restriction Fragment Length Polymorphism (RFLP) technics were used for genotypingESR1XbaII (rs9340799) and PvuII (rs22346939) variants. Results: There were statistically significant differences between the groups in terms of genotype frequencies of the ESR1PvuII (-397 T > C) variant (p = 0.049) but not for the XbaII (-351 A > G) variant (p > 0.05). However, a correlation was observed between MDD and ESR1XbaII variant after male participants were excluded (p = 0.028). Also, the high pain score of MDD patients was associated with the ESR1PvuII variant, especially in female patients (p = 0.021). According to the results of combined genotype analysis, AA-TC combined genotype was correlated with a decreased risk in patients with MDD compared to controls (p = 0.016), while the combined genotype of GGCC was associated with increased risk in the patients with MDD compared to controls (p = 0.042). Conclusion: The two ESR1 variants were associated with MDD risk and its features in both individual and combined forms.

Background: Previous studies have reported that mesenchymal stem cell (MSC)- derived exosomes can protect primary rat brain microvascular endothelial cells (BMECs) against oxygen-glucose deprivation and reoxygenation (OGD/R)-induced injury. Objective: The aim was to identify the key factors mediating the protective effects of MSC-derived exosomes. Methods: Primary rat BMECs were either pretreated or not pretreated with MSC-derived exosomes before exposure to OGD/R. Naïve cells were used as a control. After performing small RNA deep sequencing, quantitative reverse transcription polymerase chain reaction was performed to validate microRNA (miRNA) expression. The effects of rno-miR-666-3p on cell viability, apoptosis, and inflammation in OGD/R-exposed cells were assessed by performing the Cell Counting Kit 8 assay, flow cytometry, and enzyme-linked immunosorbent assay, respectively. Moreover, the role of rno-miR-666-3p in regulating gene expression in OGD/R-exposed cells was studied using mRNA deep sequencing. Lastly, to evaluate whether mitogen-activated protein kinase 1 (MAPK1) was the target of rno-miR-666-3p, western blotting and the dual-luciferase assay were performed. Results: MSC-derived exosomes altered the miRNA expression patterns in OGD/R-exposed BMECs. In particular, the expression levels of rno-miR-666-3p, rno-miR-92a-2-5p, and rnomiR- 219a-2-3p decreased in OGD/R-exposed cells compared with those in the control; however, MSC-derived exosomes restored the expression levels of these miRNAs under OGD/R conditions. rno-miR-666-3p overexpression enhanced cell viability and alleviated the apoptosis of OGD/R-exposed cells. Moreover, rno-miR-666-3p suppressed OGD/R-induced inflammation. mRNA deep sequencing revealed that rno-miR-666-3p is closely associated with the MAPK signaling pathway. Western blotting and the dual-luciferase assay confirmed that MAPK1 is the target of rnomiR- 666-3p. Conclusion: MSC-derived exosomes restore rno-miR-666-3p expression in OGD/R-exposed BMECs. Moreover, this specific miRNA exerts protective effects against OGD/R by suppressing the MAPK signaling pathway.

Introduction: Susceptibility-Eeighted Imaging (SWI) enables visualization of thrombotic material in acute ischemic stroke. We analyzed the association between thrombus length on SWI and the success rate of recanalization in stent-retriever mechanical thrombectomy. Methods: A retrospective study was performed on 128 patients with Middle Cerebral Artery (MCA) thrombus on pretreatment SWI. The patients were divided into 2 groups, the successful recanalization and the failed recanalization group. Thrombus visibility and location on SWI were compared to those on Maximum Intensity Projection (MIP) in Computed Tomography (CT) angiography. A comparative analysis was performed in terms of clinical and radiologic outcomes as well as complications with respect to multiple categories. Results: No significant differences were noted in terms of baseline characteristics and clinical outcomes between the 2 groups. However, compared with the successful recanalization group, the failed recanalization group had a larger number of stent-retriever passages and a longer thrombus length (p = 0.027 and 0.014, respectively). Multivariate analyses revealed that a larger mean number of stent-retriever passages was a predictive factor for failure of recanalization (odds ratio [OR] 1.60; 95% confidence Interval [CI] 1.12-2.08; p = 0.04). Thrombus length (OR 9.91; 95% CI 3.89-13.87; p < 0.001) and atrial fibrillation (OR 5.38; 95% CI 1.51-9.58; p = 0.008) were separately associated with more than 3 stent-retriever passages. Conclusion: Thrombus length has been identified as a predictor of recanalization failure in mechanical thrombectomy. A significant decline in the success rate of recanalization was associated with longer thrombus length.

Background: Neovascular age-related macular degeneration (AMD) with choroidal neovascularization (CNV) is a leading cause of blindness in elderly people. Anti-vascular endothelial growth factor (anti-VEGF)-drugs are used to treat AMD patients; however, some patients are resistant to these therapies. Objective: The purpose of this study was to investigate the anti-angiogenic effects of α2-adrenergic agonists, including guanabenz and clonidine. Methods: We evaluated the anti-angiogenic effects of α2-adrenergic agonists in human retinal microvascular endothelial cells (HRMECs). A proliferation assay was conducted, and the migration ratio was evaluated. In a laser-induced CNV model, guanabenz and clonidine were delivered via intraperitoneal injection or implantation of an osmotic pump device. Fourteen days following CNV induction, CNV lesion size and fundus fluorescein angiography (FFA) were evaluated. Results: Guanabenz and clonidine inhibited VEGF-induced retinal endothelial cell growth and migration. In the CNV model mice, CNV lesion sizes were reduced by intraperitoneal administration of guanabenz or clonidine. Data, including body weight, systolic blood pressure, and heart rate showed that guanabenz (0.5 and 2.0 mg/kg/day) had little effect on these parameters; conversely, a high dose of clonidine (1.0 mg/kg/day) did affect these parameters. Additionally, clonidine did not affect CNV size, but continuous administration of guanabenz attenuated both CNV size and leakage from neovessels. Conclusion: Our study suggests a key role for α2-adrenergic receptors during CNV formation. Therefore, we suggest that α2-adrenergic receptor agonists may represent novel therapeutic drugs for patients with neovascular AMD.

Objective: Our study investigated the association between the level of HbA1c (glycated hemoglobin) at admission and the prognosis of aneurysmal subarachnoid hemorrhage (SAH). Methods: A total of 510 patients treated with neuro-intervention for aneurysmal SAH and with data for admission HbA1c (glycated hemoglobin) were included. Favorable clinical outcome was defined as modified Rankin Scale (mRS) score of 0-2 at 3 months. Receiver operating characteristic (ROC) curve analysis was used to identify the optimal cutoff value of HbA1C for unfavorable clinical outcomes. Logistic regression was used to evaluate the association between HbA1C level and outcomes. Results: The optimal cutoff value of HbA1C was identified as 6.0% (P < 0.001), and patients with a high HbA1C (≥ 6.0%) had a lower prevalence of favorable clinical outcomes than patients with low HbA1C (< 6.0%) (P < 0.001). High HbA1C (≥ 6.0%) was independently associated with unfavorable clinical outcome (OR 2.84; 95% CI: 1.52-5.44; P = 0.004). The risk of unfavorable clinical outcome was significantly increased in patients with HbA1C (≥ 7.0%, < 8%) and HbA1C (≥ 8.0%) compared with lower baseline HbA1C (≥ 6.0%, < 7%) values (OR 2.17; 95% CI: 1.87-5.13; P = 0.011 and OR 4.25; 95% CI: 3.17-8.41; P = 0.005). Conclusion: Our study showed that HbA1C could be an independent predictor of worse outcomes following neuro-intervention for aneurysmal SAH. High HbA1C (≥ 6.0%) was associated with unfavorable clinical outcomes, and gradual elevation of HbA1C contributed to an increase in the risk of worse clinical outcomes after SAH.

Background: Parkinson’s disease (PD) is a neurodegenerative disorder caused by the progressive loss of dopaminergic neurons. Canopy fibroblast growth factor signaling regulator 2 (CNPY2) is down-regulated in this disease, but its functions are unknown. Objective: This study investigates the effects and regulation of CNPY2 in the apoptosis of neurons in PD. Methods: We established a PD model in vivo by a five consecutive days-injection of 1-methyl-4- phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP) to mice. In vitro, the human SH-SY5Y neuroblastoma cells, after differentiation, were treated with 1-Methyl-4-phenylpyridinium iodide (MPP+) for modeling. The cells were transfected with a recombinant vector overexpressing CNPY2 followed by MPP+ treatment. Expression of CNPY2 and proteins related to apoptosis was detected by real-time PCR, western blot, or immunofluorescence staining. The ROS level and mitochondrial membrane potential were determined by flow cytometry. Cell viability and apoptosis were measured by MTT assay and TUNEL staining. Results: CNPY2 level was down-regulated both in the brain and retina of PD mice and also inhibited in neurons by MPP+ in vitro. Overexpression of CNPY2 repressed the level of Bax and cleaved caspase-3, enhanced Bcl-2 level, and promoted neurite length under MPP+ treatment. CNPY2 overexpression reduced the accumulation of ROS and mitochondria dysfunction in neurons. The AKT/ GSK3β signaling pathway was activated by overexpressed CNPY2 to inhibit MPP+-induced neuronal apoptosis, which was confirmed using an AKT inhibitor MK-2206 2HCl. Conclusion: CNPY2 alleviates oxidative stress, mitochondria dysfunction, and apoptosis of neurons induced by MPP+ by activating the AKT/ GSK3β signaling pathway.

Background and Purpose: Reduced number and function of CD31+ circulating angiogenic cells (CACs) may explain vascular complications associated with the chronic phase stroke. The purpose of this study was to quantify CD31+ CAC paracrine function, total number and number of various subtypes of CD31+ CACs in individuals with chronic stroke compared with controls. Methods: Peripheral blood mononuclear cells were isolated from chronic stroke participants and controls. CD31+ cells were quantified by flow cytometry, as was co-expression of CD31 in combination with CD14, CD3, CD11b, or CD34. Immunomagnetically selected CD31+ cells were cultured, and conditioned medium was used in a capillary-like network assay. Results: Significantly lower levels of CD31+ CACs were found in stroke participants compared with controls (-24%; P=0.04). Additionally, CD31+/CD14+, CD31+/CD11b+ and CD31+/CD3+ cells were significantly lower in the chronic stroke group compared with controls (-45%, P=0.02; -47%, P=0.02 and -32%, P=0.03, respectively). There was no group effect on CD31+ CAC conditioned media-mediated capillary-like network formation. Conclusion: CD31+ CACs and subtypes may serve as potential therapeutic targets in chronic stroke recovery.

Objective: A retinal vein occlusion (RVO) is a relatively common retinal vascular disorder, especially in the elderly. Many experiments have been performed on patients with an RVO but performing any type of experiments and especially longitudinal experiments on humans is difficult, if not impossible, on ethical grounds. Therefore, we have created a retinal vein occlusion (RVO) model by laser irradiation of cynomolgus monkeys after intravenous injection of rose bengal. We evaluated the pathological changes of the retina, and the effects of ranibizumab, an anti-vascular endothelial growth factor (VEGF) antibody, on the characteristics of the RVO. Methods: The integrity of the vascular system was evaluated by fluorescein angiography (FA), and the retinal thickness and volume were determined by optical coherence tomography (OCT). The cytokines and growth factors in the aqueous humour were identified by multiplex profiling. Results: Our results showed that ranibizumab decreased the degree of vascular leakage and retinal edema at 1-3 days (acute phase) and 3-7 days (subacute phase), and suppressed foveal thinning at 28-42 days (chronic phase) after the laser irradiation. Ranibizumab also decreased the area of the foveal avascular zone, and the area was negatively and significantly correlated with the thickness of the ganglion cell layer (GCL) complex. Furthermore, ranibizumab reduced the increased expression of VEGF in the aqueous humor, but did not affect the expressions of interleukin-6 (IL-6), monocyte chemotactic protein-1 (MCP-1), angiopoietin-1 (ANG-1), or angiopoietin-2 (ANG-2). These findings suggest that ranibizumab attenuates the retinal edema and subsequent retinal atrophy in part by neutralizing VEGF. However, other cytokines and growth factors were also affected by the ranibizumab, which suggests that not only VEGF but also other unidentified agents might play a role in the pathogenesis of the RVO. Conclusion: We have created a non-human primate RVO model, which resembles the clinical RVO pathology. In this model, an injection of ranibizumab leads to a reduction in vascular leakage and the retinal thickness and volume by blocking the expression of VEGF. Our model might be useful for investigating the pathological mechanisms of RVOs and explore new therapeutic agents for RVO.

Neurodegenerative disorders impact more than one billion individuals worldwide and are intimately tied to metabolic disease that can affect another nine hundred individuals throughout the globe. Nicotinamide is a critical agent that may offer fruitful prospects for neurodegenerative diseases and metabolic disorders, such as diabetes mellitus. Nicotinamide protects against multiple toxic environments that include reactive oxygen species exposure, anoxia, excitotoxicity, ethanolinduced neuronal injury, amyloid (Aß) toxicity, age-related vascular disease, mitochondrial dysfunction, insulin resistance, excess lactate production, and loss of glucose homeostasis with pancreatic β-cell dysfunction. However, nicotinamide offers cellular protection in a specific concentration range, with dosing outside of this range leading to detrimental effects. The underlying biological pathways of nicotinamide that involve the silent mating type information regulation 2 homolog 1 (Saccharomyces cerevisiae) (SIRT1), the mechanistic target of rapamycin (mTOR), AMP activated protein kinase (AMPK), and mammalian forkhead transcription factors (FoxOs) may offer insight for the clinical translation of nicotinamide into a safe and efficacious therapy through the modulation of oxidative stress, apoptosis, and autophagy. Nicotinamide is a highly promising target for the development of innovative strategies for neurodegenerative disorders and metabolic disease, but the benefits of this foundation depend greatly on gaining a further understanding of nicotinamide’s complex biology.

Lipoprotein disorders are a major risk factor for atherosclerotic neuro-cardiovascular disease (ACVD) and are heavily influenced by lifestyle, including alcohol drinking. Moderate drinkers have a lower ACVD risk than abstainers due to their higher levels of high-density lipoprotein (HDL) cholesterol, an important protective factor against ACVD. On the contrary, heavy drinking increases ACVD risk. According to an extensive literature body, ethanol intoxication modifies lipid serum profile and induces endothelial dysfunction. Single nucleotide polymorphisms may influence the relationship between alcohol drinking, HDL cholesterol level, and atherosclerotic risk. The risk of ACVD in heavy drinkers seems enhanced in patients with apolipoprotein E4 allele, interleukin- 6-174 polymorphism, and cholesteryl ester transfer protein TaqIB polymorphism. Apolipoprotein E4 is a known risk factor for ACVD, while apolipoprotein E2 has mixed effects. Therefore, even if a “protective role” may be attributed to moderate drinking, this effect cannot be extended to everyone.

Background: Robust evidence has described that Parkinson´s disease (PD) is associated with an increased risk for developing epileptic seizures. In fact, an interplay between PD and epilepsy has been of interest for many years. An emerging hypothesis is that inflammation could link both diseases. Objective: Bearing in mind the experience of our group in the field of Ca²⁺/cAMP signalling pathways, this article discussed, beyond inflammation, the role of these signalling pathways in this link between PD and epilepsy. Methods: Publications involving Ca²⁺/cAMP signalling pathways, PD, and epilepsy (alone or combined) were collected by searching PubMed and EMBASE. Results: The comprehension of the interplay between PD and epilepsy could improve the drug therapy. In addition, a Ca²⁺ signalling dyshomeostasis due to Coronavirus disease 2019 (COVID-19), an emerging and rapidly evolving situation, has been reported. Conclusion: Thus, this article also debated recent findings about therapeutics involving Ca2+ channel blockers for preventing Ca²⁺ signalling dyshomeostasis due to COVID-19, including the correlation among COVID-19, epilepsy, and PD.