The presence of leukoaraiosis enhances the association between sTWEAK and hemorrhagic transformation

Systematic Mendelian Randomization Exploring Druggable Genes for Hemorrhagic Strokes

Patients with hemorrhagic stroke have high rates of morbidity and mortality, and drugs for prevention are very limited. Mendelian randomization (MR) analysis can increase the success rate of drug development by providing genetic evidence. Previous MR analyses only analyzed the role of individual drug target genes in hemorrhagic stroke; therefore, we used MR analysis to systematically explore the druggable genes for hemorrhagic stroke. We sequentially performed summary-data-based MR analysis and two-sample MR analysis to assess the associations of all genes within the database with intracranial aneurysm, intracerebral hemorrhage, and their subtypes. Validated genes were further analyzed by colocalization. Only genes that were positive in all three analyses and were druggable were considered desirable genes. We also explored the mediators of genes affecting hemorrhagic stroke incidence. Finally, the associations of druggable genes with other cardiovascular diseases were analyzed to assess potential side effects. We identified 56 genes that significantly affected hemorrhagic stroke incidence. Moreover, TNFSF12, SLC22A4, SPARC, KL, RELT, and ADORA3 were found to be druggable. The inhibition of TNFSF12, SLC22A4, and SPARC can reduce the risk of intracranial aneurysm, subarachnoid hemorrhage, and intracerebral hemorrhage. Gene-induced hypertension may be a potential mechanism by which these genes cause hemorrhagic stroke. We also found that blocking these genes may cause side effects, such as ischemic stroke and its subtypes. Our study revealed that six druggable genes were associated with hemorrhagic stroke, and the inhibition of TNFSF12, SLC22A4, and SPARC had preventive effects against hemorrhagic strokes.

Precision Medicine for Blood Glutamate Grabbing in Ischemic Stroke

Glutamate grabbers, such as glutamate oxaloacetate transaminase (GOT), have been proposed to prevent excitotoxicity secondary to high glutamate levels in stroke patients. However, the efficacy of blood glutamate grabbing by GOT could be dependent on the extent and severity of the disruption of the blood-brain barrier (BBB). Our purpose was to analyze the relationship between GOT and glutamate concentration with the patient's functional status differentially according to BBB serum markers (soluble tumor necrosis factor-like weak inducer of apoptosis (sTWEAK) and leukoaraiosis based on neuroimaging). This retrospective observational study includes 906 ischemic stroke patients. We studied the presence of leukoaraiosis and the serum levels of glutamate, GOT, and sTWEAK in blood samples. Functional outcome was assessed using the modified Rankin Scale (mRS) at 3 months. A significant negative correlation between GOT and glutamate levels at admission was shown in those patients with sTWEAK levels > 2900 pg/mL (Pearson's correlation coefficient: -0.249; p < 0.0001). This correlation was also observed in patients with and without leukoaraiosis (Pearson's correlation coefficients: -0.299; p < 0.001 vs. -0.116; p = 0.024). The logistic regression model confirmed the association of higher levels of GOT with lower odds of poor outcome at 3 months when sTWEAK levels were >2900 pg/mL (OR: 0.41; CI 95%: 0.28-0.68; p < 0.0001) or with leukoaraiosis (OR: 0.75; CI 95%: 0.69-0.82; p < 0.0001). GOT levels are associated with glutamate levels and functional outcomes at 3 months, but only in those patients with leukoaraiosis and elevated sTWEAK levels. Consequently, therapies targeting glutamate grabbing might be more effective in patients with BBB dysfunction.

Differential blood-based biomarkers of subcortical and deep brain small vessel disease

Background

Cerebral small vessel disease is the most common cause of lacunar strokes (LS). Understanding LS pathogenesis is vital for predicting disease severity, prognosis, and developing therapies.

Objectives

To research molecular profiles that differentiate LS in deep brain structures from those in subcortical white matter.

Design

Prospective case-control study involving 120 patients with imaging-confirmed LS and a 120 control group.

Methods

We examined the relationship between Alzheimer's disease biomarkers [amyloid beta (Aβ1-40, Aβ1-42)], serum inflammatory marker (interleukin-6, IL-6), and endothelial dysfunction markers [soluble tumor necrosis factor-like weak inducer of apoptosis, and pentraxin-3 (sTWEAK, PTX3)] with respect to LS occurring in deep brain structures and subcortical white matter. In addition, we investigated links between LS, leukoaraiosis presence (white matter hyperintensities, WMHs), and functional outcomes at 3 months. Poor outcome was defined as a modified Rankin scale >2 at 3 months.

Results

Significant differences were observed in levels of IL-6, PTX3, and sTWEAK between patients with deep lacunar infarcts and those with recent small subcortical infarcts (20.8 versus 15.6 pg/mL, p < 0.001; 7221.3 versus 4624.4 pg/mL, p < 0.0001; 2528.5 versus 1660.5 pg/mL, p = 0.001). Patients with poor outcomes at 3 months displayed notably higher concentrations of these biomarkers compared to those with good outcomes. By contrast, Aβ1-40 and Aβ1-42 were significantly lower in patients with deep LS (p < 0.0001). Aβ1-42 levels were significantly higher in patients with LS in subcortical white matter who had poor outcomes. WMH severity only showed a significant association with deep LS and correlated with sTWEAK (p < 0.0001).

Conclusion

The pathophysiological mechanisms of lacunar infarcts in deep brain structures seem different from those in the subcortical white matter. As a result, specific therapeutic and preventive strategies should be explored.

Elucidating the Role of Baseline Leukoaraiosis on Forecasting Clinical Outcome of Acute Ischemic Stroke Patients Undergoing Reperfusion Therapy

Stroke stands as a major cause of death and disability with increasing prevalence. The absence of clinical improvement after either intravenous thrombolysis (IVT) or mechanical thrombectomy (MT) represents a frequent concern in the setting of acute ischemic stroke (AIS). In an attempt to optimize overall stroke management, it is clinically valuable to provide important insight into functional outcomes after reperfusion therapy among patients presenting with AIS. The aim of the present review is to explore the predictive value of leukoaraiosis (LA) in terms of clinical response to revascularization poststroke. A literature research of two databases (MEDLINE and Scopus) was conducted in order to trace all relevant studies published between 1 January 2012 and 1 November 2022 that focused on the potential utility of LA severity regarding reperfusion status and clinical outcome after revascularization. A total of 37 articles have been traced and included in this review. LA burden assessment is indicative of functional outcome post-intervention and may be associated with hemorrhagic events' incidence among stroke individuals. Nevertheless, LA may not solely guide decision-making about treatment strategy poststroke. Overall, the evaluation of LA upon admission seems to have interesting prognostic potential and may substantially enhance individualized stroke care.

Need for a Paradigm Shift in the Treatment of Ischemic Stroke: The Blood-Brain Barrier

Blood-brain barrier (BBB) integrity is essential to maintaining brain health. Aging-related alterations could lead to chronic progressive leakiness of the BBB, which is directly correlated with cerebrovascular diseases. Indeed, the BBB breakdown during acute ischemic stroke is critical. It remains unclear, however, whether BBB dysfunction is one of the first events that leads to brain disease or a down-stream consequence. This review will focus on the BBB dysfunction associated with cerebrovascular disease. An added difficulty is its association with the deleterious or reparative effect, which depends on the stroke phase. We will first outline the BBB structure and function. Then, we will focus on the spatiotemporal chronic, slow, and progressive BBB alteration related to ischemic stroke. Finally, we will propose a new perspective on preventive therapeutic strategies associated with brain aging based on targeting specific components of the BBB. Understanding BBB age-evolutions will be beneficial for new drug development and the identification of the best performance window times. This could have a direct impact on clinical translation and personalised medicine.

Antihyperthermic Treatment in the Management of Malignant Infarction of the Middle Cerebral Artery

Malignant infarction of the middle cerebral artery (m-MCA) is a complication of ischemic stroke. Since hyperthermia is a predictor of poor outcome, and antihyperthermic treatment is well tolerated, our main aim was to analyze whether the systemic temperature decrease within the first 24 h was associated with a better outcome. Furthermore, we studied potential biochemical and neuroimaging biomarkers. This is a retrospective observational analysis that included 119 patients. The temperature variations within the first 24 h were recorded. Biochemical laboratory parameters and neuroimaging variables were also analyzed. The temperature increase at the first 24 h (OR: 158.97; CI 95%: 7.29−3465.61; p < 0.001) was independently associated with a higher mortality. Moreover, antihyperthermic treatment (OR: 0.08; CI 95%: 0.02−0.38; p = 0.002) was significantly associated with a good outcome at 3 months. Importantly, antihyperthermic treatment was associated with higher survival at 3 months (78% vs. 50%, p = 0.003). Significant independently associations between the development of m-MCA and both microalbuminuria (OR: 1.01; CI 95%: 1.00−1.02; p = 0.005) and leukoaraiosis (OR: 3.07; CI 1.84−5.13−1.02; p < 0.0001) were observed. Thus, antihyperthermic treatment within the first 24 h was associated with both a better outcome and higher survival. An increased risk of developing m-MCA was associated with leukoaraiosis and an elevated level of microalbuminuria.

sTWEAK is a leukoaraiosis biomarker associated with neurovascular angiopathy

Objective

Leukoaraiosis (LA) refers to white matter lesions of undetermined etiology associated with the appearance and worsening of vascular pathologies. The aim is to confirm an increased frequency and intensity of LA in symptomatic patients with neurovascular pathology compared with asymptomatic subjects, and its association with circulating serum levels of soluble tumor necrosis factor‐like weak inducer of apoptosis (sTWEAK).

Methods

An observational study was conducted in which two groups of patients were compared. Group I (N = 242) comprised of asymptomatic subjects with arterial hypertension and/or diabetes or with a history of transient ischemic attacks, and Group II (N = 382) comprised patients with lacunar stroke or deep hemispheric intracerebral hemorrhage (ICH) of hypertensive origin. Serum levels of sTWEAK were analyzed and correlated with prevalence and intensity of LA according to the Fazekas scale.

Results

The prevalence of LA was higher in symptomatic (85.1%) versus asymptomatic patients (62.0%). Logistic regression model showed a significant relation of LA with neurovascular pathologies (OR: 2.69, IC 95%: 1.10–6.59, p = 0.003). When stratified according to the Fazekas scale, LA of grade II (OR: 3.53, IC 95%: 1.10–6.59, p = 0.003) and specially grade III (OR: 4.66, 95% CI: 1.09–19.84, p = 0.037) showed correlation with neurovascular pathologies. Increased sTWEAK levels were found in the symptomatic group in all LA grades (p < 0.0001), and associated with 5.06 times more risk of presenting clinical symptoms (OR: 5.06, 95% CI: 2.66–9.75, p < 0.0001).

Interpretation

LA showed a higher prevalence in patients with symptomatic lacunar stroke or deep hemispheric ICH. There is an association between sTWEAK levels and LA degree.

sTWEAK as Predictor of Stroke Recurrence in Ischemic Stroke Patients Treated With Reperfusion Therapies

Aim: The purpose of this study was to investigate clinical and neuroimaging factors associated with stroke recurrence in reperfused ischemic stroke patients, as well as the influence of specific biomarkers of inflammation and endothelial dysfunction.

Methods: We conducted a retrospective analysis on a prospectively registered database. Of the 875 patients eligible for this study (53.9% males; mean age 69.6 ± 11.8 years vs. 46.1% females; mean age 74.9 ± 12.6 years), 710 underwent systemic thrombolysis, 87 thrombectomy and in 78, systemic or intra-arterial thrombolysis together with thrombectomy was applied. Plasma levels of interleukin 6 (IL-6) and tumor necrosis factor alpha (TNFα) were analyzed as markers of inflammation, and soluble tumor necrosis factor-like inducer of apoptosis (sTWEAK) as an endothelial dysfunction marker. The main outcome variables of the study were the presence and severity of leukoaraiosis (LA) and stroke recurrence.

Results: The average follow-up time of the study was 25 ± 13 months, during which 127 patients (14.5%) showed stroke recurrence. The presence and severity of LA was more severe in the second stroke episode (Grade III of the Fazekas 28.3 vs. 52.8%; p < 0.0001). IL-6 levels at the first admission and before reperfusion treatment in patients with and without subsequent recurrence were similar (9.9 ± 10.4 vs. 9.1 ± 7.0 pg/mL, p = 0.439), but different for TNFα (14.7 ± 5.6 vs. 15.9 ± 5.7 pg/mL, p = 0.031) and sTWEAK (5,970.8 ± 4,330.4 vs. 8,660.7 ± 5,119.0 pg/mL, p < 0.0001). sTWEAK values ≥7,000 pg/mL determined in the first stroke were independently associated to recurrence (OR 2.79; CI 95%: 1.87–4.16, p < 0.0001).

Conclusions: The severity and the progression of LA are the main neuroimaging factors associated with stroke recurrence. Likewise, sTWEAK levels were independently associated to stroke recurrence, so further studies are necessary to investigate sTWEAK as a therapeutic target.

sTWEAK is a marker of early haematoma growth and leukoaraiosis in intracerebral haemorrhage

Objective

To study the association between early growth of haematoma with biomarkers of endothelial dysfunction such as leukoaraiosis (LA) and the soluble tumour necrosis factor-like weak inducer of apoptosis (sTWEAK) in patients with intracerebral haemorrhage (ICH).

Methods

This is a retrospective observational study of patients with nontraumatic ICH. Clinical and biochemical parameters were analysed. sTWEAK levels were measured by ELISA. LA was analysed in the hemisphere without haemorrhage to avoid interference with the acute injury. The main endpoint was the haematoma growth evaluated by the difference in volume between the second and the initial neuroimage. Poor functional outcome, defined as a modified Rankin Scale >2 at 3 months, was considered as secondary endpoint. Receiver operating characteristic curve analysis was performed to stablish the best cut-off for sTWEAK levels associated with haematoma growth.

Results

We included 653 patients with ICH in our analysis (71.1±11.9 years, 44% women). Haematoma growth was observed in 188 patients (28.8%). sTWEAK levels ≥5600 pg/mL predicted ICH growth with a sensitivity of 84% and a specificity of 87%. sTWEAK levels ≥5600 pg/mL and the presence of LA were associated with haematoma growth (OR: 42.46; (CI 95% 22.67 to 79.52) and OR: 2.73 (CI 95% 1.39 to 5.34), respectively). Also, the presence of LA (OR: 4.31 (CI 95% 2.89 to 6.42)) and the interaction between ICH growth and sTWEAK (OR: 2.23 (CI 95% 1.40 to 3.55)) were associated with poor functional outcome at 3 months.

Conclusion

sTWEAKs, together with the presence and grade of LA, are biomarkers able to predict ICH growth and poor functional outcome in patients with ICH.