The potential therapeutic effect of phosphodiesterase 5 inhibitors in the acute ischemic stroke (AIS)

Metabolic Factors Mediate the Causal Effect of Physical Activity and Sedentary Behavior on Stroke and Its Subtypes: Evidence from Mendelian Randomization Study

In observational studies, physical activity and sedentary behavior are associated with the risk of stroke (overall and stroke subtypes). However, whether it is causal relevance remains to be established. Given that exercise habits can be an intervention towards preventing strokes, we assessed the causality of behavioral habits with stroke and its subtypes using Mendelian randomization (MR) approaches. Stroke was analyzed as all-cause ischemic stroke (IS), three IS subtypes including large artery stroke, small vessel stroke and cardioembolic stroke, and intracerebral hemorrhage (ICH). Univariable MR analyses revealed an association between genetically predicted leisure screen time and higher overall IS risk (odds ratio (OR), 1.12; 95% confidence interval (CI), 1.06 to 1.19; P = 1.65 × 10-4). A protective association was also reported between genetically linked moderate-to-vigorous intensity physical activity and the risk of small vessel stroke (OR, 0.52; 95% CI, 0.32 to 0.84; P = 0.008). Further reverse analyses found no causal effect of IS on leisure screen time and small vessel stroke on moderate-to-vigorous intensity physical activity. We also studied the mediating role of metabolic traits including obesity, blood lipids, blood glucose, and blood pressure via two-step MR. It was found in mediation analysis that BMI partly mediated the causal relationship between leisure screen time and all-cause IS; the mediated proportion was 26.1% (95% CI: 18.1 to 35.0%). We found evidence that a sedentary lifestyle is associated with a higher risk of overall IS, and BMI plays a mediating role in the causal pathway. Our findings provide genetic evidence for the point that active lifestyles may be an effective prevention strategy for IS.

The possible therapeutic role of advanced glycation end-product inhibitors in ischemic stroke

The advanced glycation end-products (AGEs) are toxic molecules result from non-enzymatic interactions of sugar with lipids or proteins. AGEs promote the generation of reactive oxygen species that induce the release of pro-inflammatory cytokines, and alter the intracellular signaling leading to progressive biochemical and metabolic derangements. AGEs-induced cellular aging is implicated in the development and progression of different neurological disorders such as dementia, neuropsychiatric disorders, and cerebrovascular diseases. Particularly, AGEs-induced microangiopathy and macroangiopathy trigger the induction of prothrombotic/thrombotic cascades with subsequent increase risk of acute ischemic stroke (AIS). Many studies highlighted that AGEs serum levels are correlated with the incidence, pathogenicity, and severity of AIS. However, the relationship between AGEs and AIS is not elucidated completely. Therefore, this review aims to discuss how AGEs promote the development and progression of AIS, and how AGEs inhibitors could be effective in the management of AIS.

Association of stent thrombectomy and conventional treatment with neuroprotection, complications, anxiety, and depression in acute ischemic stroke patients

BACKGROUND

Acute ischemic stroke (AIS) is an abrupt blood flow cessation to a specific brain region within a vascular zone, causing a subsequent decline in neurological capabilities. Stent thrombectomy is a recently established technique for treating AIS. It provides the benefits of being a relatively simple and safe procedure, capable of partially enhancing a patient's condition. However, some patients may experience endothelial damage and recurrent thrombosis, with clinical outcomes that are not always satisfactory. Hence, the efficacy of this method remains unclear.

AIM

To survey the association of stent thrombectomy vs standard treatment with neurological function protection, complications, and short-term prognosis in patients diagnosed with AIS.

METHODS

This study assigned 90 patients with AIS to the observation and control groups (n = 45 patients) from December 2020 to December 2022. Stent thrombectomy was conducted in the observation group, whereas routine treatment was provided to the control group. The study assessed the therapeutic outcomes of two groups, including a comparison of their neurological function, living ability, anxiety and depression status, plaque area, serum inflammatory factors, serum Smur100 β protein, neuron-specific enolase (NSE), homocysteine (Hcy), and vascular endothelial function. Additionally, the incidence of complications was calculated and analyzed for each group.

RESULTS

The total effective rate of treatment was 77.78% and 95.56% in the control and observation groups, respectively. After 8 weeks of treatment, the scores on the National Institutes of Health Stroke Scale, Hamilton Anxiety Scale, and Hamilton Depression Scale decreased remarkably; the Barthel index increased remarkably, with better improvement effects of the scores in the observation group (P < 0.05); total cholesterol, triglyceride, C-reactive protein, and plaque area lessened remarkably, with fewer patients in the observation group (P < 0.05); S-100β protein, NSE, and Hcy levels lessened remarkably, with fewer patients in the observation group (P < 0.05); serum vascular endothelial growth factor and nitric oxide synthase levels increased remarkably, whereas the endothelin-1 level decreased, with better improvement effect in the observation group (P < 0.05). Complications occurred in 8.88% of patients in the observation group compared with 33.33% in the control group.

CONCLUSION

Stent thrombectomy appeared to provide more remarkable neuroprotective effects in patients with AIS compared to the intravenous thrombolysis regimen. Additionally, it has effectively improved the neurological function, daily activities, and vascular endothelial function of patients, while reducing the incidence of complications and improving short-term prognosis.

Neuronal nitric oxide synthase activation by tadalafil protects neurological impairments in a zebrafish larva model of hyperammonemia

AIMS

Hyperammonaemia (HA) is a metabolic disorder characterized by increased ammonia levels in the blood and is associated with severe neurological impairments. Some previous findings have shown the involvement of the nitric oxide pathway in HA-induced neurological impairments. The current study explored the impact of tadalafil on neurological impairments induced by HA in a zebrafish larval model due to its reported indirect interactions with the nitric oxide pathway.

MATERIAL AND METHODS

HA was induced in zebrafish larvae by ammonium acetate exposure from 2 to 9 days post fertilization (dpf). Locomotor and cognitive functions were analysed following the treatment. The levels of gamma-aminobutyric acid (GABA), glutamate, and dopamine were measured in the larval head. The expression of genes associated with apoptosis (baxa and bcl2a), selected neurotransmitter receptors and bdnf was analysed. The protein levels of CREB and nNOS were also quantified.

KEY FINDINGS

Tadalafil incubation reversed the HA-associated locomotor and cognitive impairments in larvae. The treatment modulated GABA, dopamine, and glutamate levels. An upregulation in the expression of grin1a, gria2b, drd1b, drd2b, bdnf, and bcl2a, and downregulation of gabrz, gabrd, gabrg2 and baxa was observed following tadalafil treatment. The protein expression showed increased nNOS, p-CREB(Ser133), and decreased p-nNOS(Ser847) levels in the larvae incubated with tadalafil.

SIGNIFICANCE

The study concluded that tadalafil mitigates HA-induced neurological impairments by activating neuronal nitric oxide synthase. The study highlighted the possible application of tadalafil in the symptomatic management of neurological impairments in HA provided its efficacy and safety are further ensured in higher mammals.

Reinforcement of Transdural Angiogenesis: A Novel Approach to Treating Ischemic Stroke With Cerebral Perfusion Impairment

Cerebral hypoperfusion plays a critical role in early neurological deterioration and long-term outcomes in patients with acute ischemic stroke, which remains a major global health challenge. This review explored transdural angiogenesis as a promising therapeutic strategy to restore cerebral perfusion in patients with ischemic stroke. The multiple burr hole procedure has been preliminarily used as an indirect revascularization method to induce transdural arteriogenesis. Theoretically, its efficacy could be enhanced by combining it with angiogenic boosters, such as erythropoietin. Recent clinical and preclinical studies have revealed that this combination therapy promotes angiogenesis and arteriogenesis, leading to successful revascularization across the dura mater and improved cerebral blood flow. This strategy may be particularly beneficial for high-risk patients with recurrent ischemic events, such as those with moyamoya disease or intracranial arterial occlusion, representing an effective strategy when conventional medical treatments are insufficient. This review highlights the potential of transdural angiogenesis enhancement as a novel intervention for ischemic stroke, offering an alternative to thrombolysis or endovascular treatment, particularly in acute stroke patients with impaired cerebral perfusion. This approach has the potential to bridge the treatment gap for patients outside the therapeutic window for acute stroke interventions. Although further research is required to refine this technique and validate its efficacy in broader clinical settings, early results have revealed promising outcomes at reducing stroke-related complications and improving patient prognosis. This review indicates that this novel strategy may offer hope for managing ischemic stroke and related conditions associated with significant cerebral hypoperfusion.

Association of Lipoprotein-Associated Phospholipase A2 and Lipoprotein(a) With the Risk of Recurrence Stroke in Patients With Acute Ischemic Stroke

OBJECTIVE

It is still a major global challenge to reduce the high morbidity and mortality of acute ischemic stroke (AIS) and improve the prognosis of patients. This study aims to investigate the prognostic value of lipoprotein-associated phospholipase A2 (Lp-PLA2) combined with lipoprotein(a) (Lp(a)) for long-term stroke recurrence in patients with AIS.

METHODS

This study included 580 patients with AIS. Assessment of Lp-PLA2 and Lp(a) levels was conducted upon patient admission. Continuous monitoring over the long term categorized stroke recurrence as an endpoint. Patients were categorized based on these identified thresholds to compare the risk of stroke recurrence: high Lp-PLA2 and high Lp(a), high Lp-PLA2 and low Lp(a), low Lp-PLA2 and high Lp(a), and low Lp-PLA2 combined with low Lp(a).

RESULTS

Among the 580 participants, 101 individuals (17.41%) experienced stroke recurrence within the 2-year follow-up. The majority were male (61.39%), with a median age of 62 years (interquartile range: 55-69.5). Factors independently associated with heightened the risk of recurrence stroke comprised age (hazard ratio [HR], 1.025; p = 0.021), diabetes mellitus (HR, 1.751; p = 0.007), Lp-PLA2 (HR, 1.004; p < 0.001), and Lp(a) (HR, 1.002; p < 0.001). Noteworthy is that the combination of Lp-PLA2 and Lp(a) displayed superior predictive efficacy for long-term stroke recurrence risk in AIS patients compared to individual factors.

CONCLUSION

This investigation underscores the potential advantage of leveraging the combined impact of Lp-PLA2 in conjunction with Lp(a) as a more precise and cost-effective predictive tool for the risk of recurrence stroke in patients with AIS.

Correlation analysis of inflammatory markers with the short-term prognosis of acute ischaemic stroke

Stroke is the second leading cause of death worldwide, and China has the highest stroke incidence in the world. The systemic inflammatory response index (SIRI), systemic inflammatory response index (SIRI), systemic immune-inflammatory index (SII), neutrophil-to-high-density lipoprotein ratio (NHR), neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR) and monocyte-to-lymphocyte ratio (MLR) have clinical in predicting the prognosis of acute ischaemic stroke (AIS) patients. No studies have compared the predictive value of these six composite inflammatory markers. This study included 516 AIS patients with AIS symptoms for < 24 h. The short-term prognosis of AIS patients at 30 days was assessed using the modified Rankin scale (mRS), an mRS score > 2 defining poor prognosis. The results of the univariate analysis showed that all six composite inflammatory indices, SIRI, SII, NHR, NLR, PLR and MLR, were associated with a poor prognosis in patients with AIS. All six composite inflammatory indicators correlated with the short-term prognosis of AIS patients. The six composite inflammation indicators were included in the binary logistic regression, and the results showed that SIRI, NLR and PLR were found to be independent risk factors for poor short-term prognosis in AIS patients. Among the six inflammatory markers, SIRI, NLR and PLR were the most clinically valuable for predicting the short-term prognosis of patients with AIS. Peripheral blood indices are easy to obtain clinically and can provide important clinical value for early prognosis and treatment adjustment.

Irisin/PGC-1α/FNDC5 pathway in Parkinson's disease: truth under the throes

Parkinson's disease (PD) is considered one of the most common neurodegenerative brain diseases which involves the deposition of α-synuclein. Irisin hormone, a newly discovered adipokine, has a valuable role in diverse neurodegenerative diseases. Therefore, this review aims to elucidate the possible role of the irisin hormone in PD neuropathology. Irisin hormone has a neuroprotective effect against the development and progression of various neurodegenerative disorders by increasing the expression of brain-derived neurotrophic factor (BDNF). Irisin hormone has anti-inflammatory, anti-apoptotic, and anti-oxidative impacts, thereby reducing the expression of the pro-inflammatory cytokines and the progression of neuroinflammation. Irisin-induced PGC-1α could potentially prevent α-synuclein-induced dopaminergic injury, neuroinflammation, and neurotoxicity in PD. Inhibition of NF-κB by irisin improves PGC-1α and FNDC5 signaling pathway with subsequent attenuation of PD neuropathology. Therefore, the irisin/PGC-1α/FNDC5 pathway could prevent dopaminergic neuronal injury. In conclusion, the irisin hormone has a neuroprotective effect through its anti-inflammatory and antioxidant impacts with the amelioration of brain BDNF levels. Further preclinical and clinical studies are recommended in this regard.

The probable role of tissue plasminogen activator/neuroserpin axis in Alzheimer's disease: a new perspective

Alzheimer's disease (AD) is the most common type of dementia associated with amyloid beta (Aβ) deposition. Dysfunction of the neuronal clearance pathway promotes the accumulation of Aβ. The plasminogen-activating system (PAS) is controlled by various enzymes like tissue plasminogen activators (tPA). Neuronal tPA enhances the conversion of plasminogen to plasmin, which cleaves Aβ; this function is controlled by many inhibitors of PAS, including a plasminogen-activating inhibitor (PAI-1) and neuroserpin. Therefore, the objective of the present narrative review was to explore the potential role of tPA/neuroserpin in the pathogenesis of AD. PAI-1 activity is increased in AD, which is involved in accumulating Aβ. Progressive increase of Aβ level during AD neuropathology is correlated with the over-production of PAI-1 with subsequent reduction of plasmin and tPA activities. Reducing plasmin and tPA activities promote Aβ by reducing Aβ clearance. Neuroserpin plays a critical role in the pathogenesis of AD as it regulates the expression and accumulation of Aβ. Higher expression of neuroserpin inhibits the neuroprotective tPA and the generation of plasmin with subsequent reduction in the clearance of Aβ. These observations raise conflicting evidence on whether neuroserpin is neuroprotective or involved in AD progression. Thus, neuroserpin over-expression with subsequent reduction of tPA may propagate AD neuropathology.

The lncRNA lnc_AABR07044470.1 promotes the mitochondrial-damaged inflammatory response to neuronal injury via miR-214-3p/PERM1 axis in acute ischemic stroke

PURPOSE

We investigated the role of lnc_AABR07044470.1 on the occurrence and development of acute ischemic stroke (AIS) and neuronal injury by targeting the miR-214-3p/PERM1 axis to find a novel clinical drug target and prediction and treatment of AIS.

METHODS

The mouse AIS animal model was used in vivo experiments and hypoxia/reoxygenation cell model in vitro was established. Firstly, infarction volume and pathological changes of mouse hippocampal neurons were detected using HE staining. Secondly, rat primary neuron apoptosis was detected by flow cytometry assay. The numbers of neuron, microglia and astrocytes were detected using immunofluorescence (IF). Furthermore, binding detection was performed by bioinformatics database and double luciferase reporter assay. Lnc_AABR07044470.1 localization was performed using fluorescence in situ hybridization (FISH).Lnc_AABR07044470.1, miR-214-3pand PERM1mRNA expression was performed using RT-qPCR. NLRP3, ASC, Caspase-1 and PERM1 protein expression was performed using Western blotting. IL-1β was detected by ELISA assay.

RESULTS

Mouse four-vessel occlusion could easily establish the animal model, and AIS animal model had an obvious time-dependence. HE staining showed that, compared with the sham group, infarction volume and pathological changes of mouse hippocampal neurons were deteriorated in the model group. Furthermore, compared with the sham group, neurons were significantly reduced, while microglia and astrocytes were significantly activated. Moreover, the bioinformatics prediction and detection of double luciferase reporter confirmed the binding site of lnc_AABR07044470.1 to miR-214-3p and miR-214-3p to Perm1. lnc_AABR07044470.1 and PERM1 expression was significantly down-regulated and miR-214-3pexpression was significantly up-regulated in AIS animal model in vivo. At the same time, the expression of inflammasome NLRP3, ASC, Caspase-1 and pro-inflammatory factor IL-1β was significantly up-regulated in vivo and in vitro. The over-expression of lnc_AABR07044470.1 and miR-214-3p inhibitor could inhibit the neuron apoptosis and the expression of inflammasome NLRP3, ASC, Caspase-1 and pro-inflammatory factor IL-1β and up-regulate the expression of PERM1 in vitro. Finally, over-expression of lnc_AABR07044470.1 and miR-214-3p inhibitor transfected cell model was significant in relieving the AIS and neuronal injury.

CONCLUSION

Lnc_AABR07044470.1 promotes inflammatory response to neuronal injury via miR-214-3p/PERM1 axis in AIS.