Cerebral Arterial Stiffness as A New Marker of Early Stage Atherosclerosis of The Cerebral Large Artery in Acute Stroke

Central arterial stiffening and intracranial atherosclerosis: the atherosclerosis risk in communities neurocognitive study (ARIC-NCS): Aortic stiffness & intracranial atherosclerosis

OBJECTIVES

Previous studies suggest an association between central arterial stiffness (CAS) and intracranial atherosclerotic disease (ICAD) among Asian participants with stroke or hypertension; this association has not been evaluated in United States populations. We assessed the cross-sectional association of CAS with ICAD presence and burden in late-life, and differences in association by age, sex, and race.

MATERIALS AND METHODS

We conducted a cross-sectional analysis of 1,285 Atherosclerosis Risk in Communities Study participants [mean age 75 (standard deviation: 5) years, 38 % male, 20  % Black] at Visit 5 (2011-2013). CAS was measured as carotid-femoral pulse wave velocity (cfPWV) using the Omron VP-1000 Plus. ICAD was assessed using high-resolution vessel wall MRI and MR angiography. We evaluated associations of a 1 standard deviation (SD) cfPWV (3.02 m/s) and high vs. non-high cfPWV (≥ 13.57 m/s vs. < 13.57 m/s) with presence of plaques (yes/no) and plaque number (0, 1-2, and >2) using multivariable logistic and ordinal logistic regression models adjusted for covariates.

RESULTS

Each one SD greater cfPWV was associated with higher odds of plaque presence (odds ratio (OR)=1.32, 95 % confidence interval (CI): 1.22, 1.43), and an incrementally higher odds of number of plaques (OR 1-2 vs. 0 plaques = 1.21, 95 % CI: 1.10, 1.33; OR >2 vs. 0 plaques = 1.51, 95 % CI: 1.33,1.71). Results suggested differences by race, with greater magnitude associations among Black participants.

CONCLUSIONS

CAS was positively associated with ICAD presence and burden; cfPWV may be a useful subclinical vascular measure for identification of individuals who are at high risk for cerebrovascular disease.

Cerebral Arterial Stiffness as Measured Based on the Pulse Wave Velocity is Associated With Intracranial Artery Calcification in Patients With Acute Stroke

BACKGROUND AND PURPOSE

By measuring a newly defined parameter, the carotid-cerebral pulse wave velocity (ccPWV), this study aimed to determine the association of intracranial artery calcification (IAC) with arterial stiffness as reflected by the pulse wave velocity between the carotid and middle cerebral arteries using transcranial Doppler sonography in patients with acute stroke.

METHODS

We recruited 146 patients with ischemic stroke from our stroke center. Computed tomography of the head was used to assess the presence and severity of IAC. Arterial stiffness was evaluated using ccPWV. Data are presented as quartiles of ccPWV. A multivariable logistic regression model was used to assess the independent relationship between ccPWV and IAC.

RESULTS

The IAC prevalence increased with the ccPWV quartile, being 54%, 76%, 83%, and 89% for quartiles 1, 2, 3, and 4, respectively (p<0.001) as did IAC scores, with median [interquartile range] values of 0 [0-2], 3 [2-4], 4 [2-5], and 5 [4-6], respectively (p<0.001). After additionally adjusting for age and hypertension, a significant correlation was only found between quartiles 3 and 4 of ccPWV and IAC scores. The odds ratio (95% confidence interval) for the IAC scores was 1.78 (1.28-2.50) (p=0.001) in quartile 4 of ccPWV and 1.45 (1.07-1.95) (p=0.015) in quartile 3 compared with quartile 1.

CONCLUSIONS

We found that in patients with acute ischemic stroke, ccPWV was positively related to the degree of IAC. Future longitudinal cohort studies may help to identify the potential role of IAC in the progression of cerebral arterial stiffness.

Interactions Between Kidney Function and Cerebrovascular Disease: Vessel Pathology That Fires Together Wires Together

The kidney and the brain, as high-flow end organs relying on autoregulatory mechanisms, have unique anatomic and physiological hemodynamic properties. Similarly, the two organs share a common pattern of microvascular dysfunction as a result of aging and exposure to vascular risk factors (e.g., hypertension, diabetes and smoking) and therefore progress in parallel into a systemic condition known as small vessel disease (SVD). Many epidemiological studies have shown that even mild renal dysfunction is robustly associated with acute and chronic forms of cerebrovascular disease. Beyond ischemic SVD, kidney impairment increases the risk of acute cerebrovascular events related to different underlying pathologies, notably large artery stroke and intracerebral hemorrhage. Other chronic cerebral manifestations of SVD are variably associated with kidney disease. Observational data have suggested the hypothesis that kidney function influences cerebrovascular disease independently and adjunctively to the effect of known vascular risk factors, which affect both renal and cerebral microvasculature. In addition to confirming this independent association, recent large-scale human genetic studies have contributed to disentangling potentially causal associations from shared genetic predisposition and resolving the uncertainty around the direction of causality between kidney and cerebrovascular disease. Accelerated atherosclerosis, impaired cerebral autoregulation, remodeling of the cerebral vasculature, chronic inflammation and endothelial dysfunction can be proposed to explain the additive mechanisms through which renal dysfunction leads to cerebral SVD and other cerebrovascular events. Genetic epidemiology also can help identify new pathological pathways which wire kidney dysfunction and cerebral vascular pathology together. The need for identifying additional pathological mechanisms underlying kidney and cerebrovascular disease is attested to by the limited effect of current therapeutic options in preventing cerebrovascular disease in patients with kidney impairment.

The Longitudinal Distribution and Stability of Curved Basilar Artery Plaque: A Study Based on HR-MRI

AIMS

This study aims to evaluate the differences in the characteristics of atherosclerotic plaques in the proximal, curved, and distal segments of the curved basilar artery (BA) through high-resolution magnetic resonance imaging(HR-MRI).

METHODS

The imaging and clinical data of 146 patients were retrospectively analyzed. On the basis of three-dimensional (3D) time -of -flight magnetic resonance angiography (3D-TOF-MRA), 51 patients with BA curvature were selected for the study. The BA plaque is divided into three groups: proximal, curved, and distal. Plaques were identified and analyzed according to spin echo acquisition imaging via T1-weighted 3D volumetric isotropic Tse acquisition (T1W-3D -VISTA), and compare the differences in clinical related factors and plaque characteristics between groups. Diffusion-weighted imaging (DWI) and/or T2WI identified brainstem infarction. The patients were divided into symptomatic and asymptomatic groups. The correlation between plaque location and symptoms was identified and analyzed.

RESULTS

Among 51 patients, a total of 376 plaques were detected. Plaques in the proximal and curved segments are more common than those in the distal segments. Proximal plaques are more likely to have intraplaque hemorrhage ( P=0.002 ＜0.05). There was no significant difference in the distribution of criminal plaques and non-criminal plaques between each group (P=0.36 ＞0.05).

CONCLUSION

Plaques in the proximal and curved segments of the BA are more common than those in the distal segments. The proximal plaque is more prone to intraplaque hemorrhage.

Altered lncRNAs Transcriptomic Profiles in Atherosclerosis-Induced Ischemic Stroke

Long non-coding RNAs (lncRNAs) can not only regulate gene transcription and translation, but also participate in the development of central nervous system diseases as epigenetic modification factors. However, their functional significance in atherosclerosis-induced ischemic stroke (AIIS) is unclear. The study aimed to screen out differentially expressed lncRNAs (delncRNAs), and to elucidate their potential regulatory mechanisms in the pathophysiology of AIIS. Based on the clinicopathological features and clinical images, we screened out 10 patients with AIIS and recruited 10 healthy volunteers. Then we used microarray to detect the whole blood RNA of subjects, and explored the biological functions of delncRNAs by GO and KEGG analysis. After further analyzing the delncRNAs of THP-1 stimulated with ox-LDL, selective lncRNAs were screened and a corresponding lncRNA-mRNA interaction network was constructed through co-expression analysis. We yielded 180 delncRNAs (44 up-regulated and 136 down-regulated) and 218 demRNAs (45 up-regulated and 173 down-regulated). Lnc-SCARNA8 and lnc-SNRPN-2 are the most significant elevated and decreased lncRNA in AIIS, respectively. The delncRNAs may play a significant role in ubiquitination-mediated protein degradation signaling pathways. According to lncRNA-mRNA network, the expression of vacuolar protein sorting 13 homolog B (VPS13B) and biliverdin reductase B (BLVRB) were significantly regulated. Our findings suggest that the ubiquitinated proteasome pathway, VPS13B and BLVRB may play a fundamental role in the pathological process of AIIS.

Associations of Arterial Stiffness and Carotid Atherosclerosis with Cerebral Small Vessel Disease in a Rural Community-Based Population

AIMS

We aimed to examine the associations of four extracranial artery indicators with cerebral small vessel disease (CSVD) and its total burden.

METHODS

A total of 904 individuals aged 55-65 years old were included from the Taizhou Imaging Study. CSVD markers, including lacunes (LAC), white matter hyperintensities (WMH), cerebral microbleeds (CMB), and perivascular spaces (PVS), were rated based on brain magnetic resonance imaging. We also measured extracranial artery indices, including the brachial-ankle pulse wave velocity (baPWV), the ankle-brachial index, the carotid intima-media thickness (IMT), and carotid plaque. Linear and binary logistic regressions were adopted to test the associations among these four artery indicators and each CSVD marker when appropriate. Additionally, ordinal and multinomial logistic regressions were performed to assess the relationships between artery indicators and total CSVD score (range from 0-4 points).

RESULTS

A total of 443 (49.0%) participants were found to have at least one of the CSVD markers, including 172 (19.0%) with WMH, 184 (20.4%) with LAC, 147 (16.3%) with CMB, and 226 (25.0%) with PVS. Increased baPWV was significantly associated with each CSVD marker, increasing carotid IMT was associated with LAC and PVS, and the presence of carotid plaque was associated with WMH volume and PVS. Moreover, per SD increment of baPWV (odds ratio [OR]: 1.29, 95% confidence interval [CI]: 1.11-1.50) and the presence of carotid plaque (OR: 1.42, 95% CI: 1.05-1.92) were significantly associated with greater total CSVD scores.

CONCLUSION

Increased baPWV and the presence of carotid plaque appear to be associated with total CSVD burden in rural regions in China.

Impact of High Salt Diet on Cerebral Vascular Function and Stroke in Tff3-/-/C57BL/6N Knockout and WT (C57BL/6N) Control Mice

High salt (HS) dietary intake leads to impaired vascular endothelium-dependent responses to various physiological stimuli, some of which are mediated by arachidonic acid (AA) metabolites. Transgenic Tff3^−/− gene knockout mice (Tff3^−/−/C57BL/6N) have changes in lipid metabolism which may affect vascular function and outcomes of stroke. We aimed to study the effects of one week of HS diet (4% NaCl) on vascular function and stroke induced by transient occlusion of middle cerebral artery in Tff3^−/− and wild type (WT/C57BL/6N) mice. Flow-induced dilation (FID) of carotid artery was reduced in WT-HS mice, but not affected in Tff3^−/−-HS mice. Nitric oxide (NO) mediated FID. NO production was decreased with HS diet. On the contrary, acetylcholine-induced dilation was significantly decreased in Tff3^−/− mice on both diets and WT-HS mice. HS intake and Tff3 gene depletion affected the structural components of the vessels. Proteomic analysis revealed a significant effect of Tff3 gene deficiency on HS diet-induced changes in neuronal structural proteins and acute innate immune response proteins’ expression and Tff3 depletion, but HS diet did not increase the stroke volume, which is related to proteome modification and upregulation of genes involved mainly in cellular antioxidative defense. In conclusion, Tff3 depletion seems to partially impair vascular function and worsen the outcomes of stroke, which is moderately affected by HS diet.