Association between Anatomical Variations of the Circle of Willis and Covert Vascular Brain Injury in the General Population.

BACKGROUND AND PURPOSE: The circle of Willis (COW) is a circulatory anastomosis located at the base of the brain. Little is known about the association between covert vascular brain injury and COW configurations in the general population. We explored this relationship in a community-based Chinese sample. METHODS: A total of 1,055 patients (mean age, 54.8 ± 8.9 years; 36.0% men) without intracranial arterial stenosis were included in the analysis. Magnetic resonance imaging was performed to evaluate the presence of imaging markers of covert vascular brain injury, including white matter hyperintensities (WMHs), lacunes, cerebral microbleeds (CMBs), enlarged perivascular spaces, and brain atrophy. Magnetic resonance angiography was used to classify the COW configurations according to the completeness, symmetry, and presence of the fetal posterior cerebral artery (FTP). The association between vascular lesions and variations in COW was analyzed. RESULTS: Among the 1,055 patients, 104 (9.9%) had a complete COW. Completeness correlated with age (p = 0.001). Incomplete COW was positively associated with WMH severity (OR = 2.071; 95% CI, 1.004-4.270) and CMB presence (OR = 1.542; 95% CI, 1.012-2.348), independent of age and sex. The presence of FTP was associated with lacunes (OR = 1.878; 95% CI, 1.069-3.298), more severe WMHs (OR = 1.739; 95% CI, 1.064-2.842), and less severe enlarged perivascular spaces (OR = 0.562; 95% CI, 0.346-0.915). CONCLUSIONS: COW configuration was significantly related to various covert vascular brain injuries.

Different Types of Circulatory Inflammatory Biomarkers Associated with Cerebral Arterial Atherosclerosis and Dolichoectasia.

BACKGROUND: Although inflammation is found to be related to arteriopathy pathogenesis, it is yet to be determined the distinct correlations of specific inflammatory biomarker types contributing to different cerebral large vessel diseases. We aimed to investigate the association between multiple inflammatory biomarkers and cerebral atherosclerosis and dolichoectasia in a community-based sample. METHODS: A total of 960 participants of the Shunyi study were included. A panel of 14 circulatory inflammatory biomarkers was assessed and then grouped in three sets as systemic, endothelial-related, and media-related inflammation, based on underlying different inflammatory cascades. Intracranial atherosclerotic stenosis (ICAS), dolichoectasia estimated by magnetic resonance angiography, and carotid plaques estimated by ultrasound were also performed. RESULTS: Endothelial-related inflammatory group was related to the presence of ICAS (R2 = 0.215, p = 0.024) and carotid plaques (R2 = 0.342, p = 0.013). Backward stepwise elimination showed that E-selectin was prominent (ß = 0.67, 95% CI: 0.54-0.85, p = 0.001; ß = 0.79, 95% CI: 0.68-0.93, p = 0.005). Systemic inflammatory group was associated with an increased basilar artery diameter (R2 = 0.051, p < 0.001), and backward stepwise elimination showed that IL-6 was prominent (ß = 0.07, 95% CI: 0.03-0.11, p < 0.001). CONCLUSION: Different types of inflammatory biomarkers were associated with atherosclerosis and dolichoectasia, respectively, implying dissimilar inflammatory processes. Further confirming of their distinct anti-inflammatory roles as potential therapeutic targets is warrant.

Rare NOTCH3 Variants in a Chinese Population-Based Cohort and Its Relationship With Cerebral Small Vessel Disease.

BACKGROUND AND PURPOSE: Researches on rare variants of NOTCH3 in the general Chinese population are lacking. This study aims to describe the spectrum of rare NOTCH3 variants by whole-exome sequencing in a Chinese community-based cohort and to investigate the association between rare NOTCH3 variants and age-related cerebral small vessel disease. METHODS: The cross-sectional study comprised 1065 participants who underwent whole-exome sequencing and brain magnetic resonance imaging. NOTCH3 variants with minor allele frequency<1% in all 4 public population databases (1000 Genomes, ESP6500siv2_ALL, GnomAD_ALL, and GnomAD_EAS) were defined as rare variants. Multivariable linear and logistic regressions were used to investigate the associations between rare NOTCH3 variants and volume of white matter hyperintensities and cerebral small vessel disease burden. Clinical and imaging characteristics of rare NOTCH3 variant carriers were summarized. RESULTS: Sixty-five rare NOTCH3 variants were identified in 147 of 1065 (13.8%) participants, including 57 missense single nucleotide polymorphisms (SNPs), 5 SNPs in splice branching sites, and 3 frameshift deletions. A significantly higher volume of white matter hyperintensities and heavier burden of cerebral small vessel disease was found in carriers of rare NOTCH3 EGFr (epidermal growth factor-like repeats)-involving variants, but not in carriers of EGFr-sparing variants. The carrying rate of rare EGFr-involving NOTCH3 variants in participants with dementia or stroke was significantly higher than those without dementia or stroke (12.4% versus 6.6%, P=0.041). Magnetic resonance imaging signs suggestive of CADASIL were found in 3.4% (5/145) rare EGFr cysteine-sparing NOTCH3 variant carriers but not in 2 cysteine-altering NOTCH3 variant carriers. CONCLUSIONS: Carriers of rare NOTCH3 variants involving the EGFr domain may be genetically predisposed to age-related cerebral small vessel disease in the general Chinese population.

Host Prdx6 contributing to the intracellular survival of Brucella suis S2 strain.

BACKGROUND: Brucellosis is a worldwide zoonotic infectious disease that is transmitted in various ways and causes great harm to humans and animals. The brucellosis pathogen is Brucella, which mainly resides in macrophage cells and survives and replicates in host cells. However, the mechanisms underlying Brucella survival in macrophage cells have not been thoroughly elucidated to date. Peroxiredoxin 6 (Prdx6) is a bifunctional protein that shows not only GSH peroxidase activity but also phospholipase A2 activity and plays important roles in combating oxidative damage and regulating apoptosis. RESULTS: Recombinant mouse (Mus musculus) Prdx6 (MmPrdx6) was expressed and purified, and monoclonal antibodies against MmPrdx6 were prepared. Using the Brucella suis S2 strain to infect RAW264.7 murine macrophages, the level of intracellular Prdx6 expression first decreased and later increased following infection. Overexpressing Prdx6 in macrophages resulted in an increase in B. suis S2 strain levels in RAW264.7 cells, while knocking down Prdx6 reduced the S2 levels in cells. CONCLUSIONS: Host Prdx6 can increase the intracellular survival of B. suis S2 strain and plays a role in Brucella infection.

Intracranial Arterial Dolichoectasia and Stenosis: Risk Factors and Relation to Cerebral Small Vessel Disease.

BACKGROUND AND PURPOSE: Intracranial arterial dolichoectasia (IADE) is a poorly understood arteriopathy compared with intracranial atherosclerotic stenosis (ICAS). We aimed to investigate the risk factors of IADE and ICAS and their relationship with neuroimaging markers of cerebral small vessel disease in a population-based study. METHODS: This study comprised 1237 participants (aged 57.2±9.4 years, 37.6% men) who underwent brain magnetic resonance imaging and magnetic resonance angiography. IADE was assessed based on basilar artery dolichoectasia (diameter, height of bifurcation, and laterality of basilar artery) and dilation of basilar artery and internal carotid artery (intracranial volume-adjusted diameter ≥2 SD). ICAS was defined as any degree of stenosis in at least 1 intracranial artery. The neuroimaging markers of cerebral small vessel disease, including lacunes, white matter hyperintensities, microbleeds, dilated perivascular spaces, and brain atrophy, were evaluated. RESULTS: Basilar arterial dolichoectasia was observed in 3.6% (45/1237); intracranial arterial dilation in 5.9% (67/1142); and ICAS in 15.7% (194/1237). Older age, higher systolic blood pressure, diabetes mellitus, higher LDL-C (low-density lipoprotein cholesterol) and lower HDL-C (high-density lipoprotein cholesterol) were associated with the presence of ICAS (all P<0.001), whereas only older age was associated with IADE. ICAS was associated with lacunes (odds ratio, 2.91; 95% confidence interval, 1.96-4.34; P<0.001), increased white matter hyperintensities volume (ß±SE, 0.54±0.13; P<0.001), and brain atrophy (ß±SE, -1.16±0.21; P<0.001), whereas basilar arterial dolichoectasia was mainly associated with dilated perivascular spaces in basal ganglia (odds ratio, 2.20; 95% confidence interval, 1.20-4.02; P=0.01) and, to a lesser extent, associated with lacunes and microbleeds. CONCLUSIONS: IADE and ICAS had different risk factor profiles and associated with different imaging phenotypes of cerebral small vessel disease, suggesting different underlying mechanisms.

The consequence of cerebral small vessel disease: Linking brain atrophy to motor impairment in the elderly.

In the elderly, brain structural deficits and gait disturbances due to cerebral small vessel disease (CSVD) have been well demonstrated. The relationships among CSVD, brain atrophy, and motor impairment, however, are far from conclusive. Particularly, the effect of CSVD on subcortical nuclear atrophy, motor performance of upper extremities, and associating patterns between brain atrophy and motor impairment remains largely unknown. To address these gaps, this study recruited 770 community-dwelling subjects (35-82 years of age), including both CSVD and non-CSVD individuals. For each subject, four motor tests involving upper and lower extremities were completed. High-resolution structural MRI was applied to extract gray matter (GM) volume, white matter volume, cortical thickness, surface area, and subcortical nuclear (caudate, putamen, pallidum, and thalamus) volumes. The results showed worse motor performance of lower extremities but relatively preserved performance of upper extremities in the CSVD group. Intriguingly, there was a significant association between the worse performance of upper extremities and atrophy of whole-brain GM and pallidum in the CSVD group but not in the non-CSVD group. In addition, mediation analysis confirmed a functional CSVD-to-"brain atrophy"-to-"motor impairment" pathway, that is, a mediating role of thalamic atrophy in the CSVD effect on walking speed in the elderly, indicating that CSVD impairs walking performance through damaging the integrity of the thalamus in aging populations. These findings provide important insight into the functional consequences of CSVD and highlight the importance of evaluating upper extremities functions and exploring their brain mechanisms in CSVD populations during aging.

Molecular characterization and differential expression analysis of interleukin 1ß from Ovis aries.

The interleukin-1 family is an important component of the innate immune system and plays an important role in regulating immune responses on the invasion of intracellular parasites in the acquired immune system. Interleukin 1ß (IL-1ß) is one of the members of the IL-1 family that predominantly activates downstream signaling pathways to play immunological functions of stimulating T and B lymphocyte activation and promoting the various syntheses of inflammatory substances in conjunction with other cytokines. Here, a full-length IL-1ß cDNA (OaIL-1ß) of sheep (Ovis aries) was cloned using rapid amplification of cDNA ends (RACE), which consists of 1494 bp and contains a 5'-UTR region with a length of 83 bp, a complete ORF of 801 bp in length, and a 3'-UTR region with a length of 642 bp. Recombinant protein OaIL-1ß was expressed and purified, and the monoclonal antibody against IL-1ß of sheep is prepared. Western blotting results showed that the sheep IL-1ß protein was detected in the heart, liver, lung, kidney, stomach, intestine, muscle, lymph nodes and leukocytes with the highest expression in the muscle and the lowest expression in the lung. Different bacteria treating sheep white blood cells induced differential expression of OaIL-1ß. Compared with the normal sheep, OaIL-1ß in the buffy coat was differentially expressed in the Brucella melitensis-challenged group and the B. suis S2 strain-inoculated group. However, whether IL-1ß may be considered as a molecular biomarker for differing Brucella-infected animals from brucellosis-vaccinated animals or not need to be further studied.

Dynamic Mechanism of Cerebral Venous Disruption: Longitudinal Evidence From a Community-Based Cohort.

BACKGROUND: This study aims to investigate the temporal and spatial patterns of structural brain injury related to deep medullary veins (DMVs) damage. METHODS AND RESULTS: This is a longitudinal analysis of the population-based Shunyi cohort study. Baseline DMVs numbers were identified on susceptibility-weighted imaging. We assessed vertex-wise cortex maps and diffusion maps at both baseline and follow-up using FSL software and the longitudinal FreeSurfer analysis suite. We performed statistical analysis of global measurements and voxel/vertex-wise analysis to explore the relationship between DMVs number and brain structural measurements. A total of 977 participants were included in the baseline, of whom 544 completed the follow-up magnetic resonance imaging (age 54.97±7.83 years, 32% men, mean interval 5.56±0.47 years). A lower number of DMVs was associated with a faster disruption of white matter microstructural integrity, presented by increased mean diffusivity and radial diffusion (ß=0.0001 and SE=0.0001 for both, P=0.04 and 0.03, respectively), in extensive deep white matter (threshold-free cluster enhancement P<0.05, adjusted for age and sex). Of particular interest, we found a bidirectional trend association between DMVs number and change in brain volumes. Specifically, participants with mild DMVs disruption showed greater cortical enlargement, whereas those with severe disruption exhibited more significant brain atrophy, primarily involving clusters in the frontal and parietal lobes (multiple comparison corrected P<0.05, adjusted for age, sex, and total intracranial volume). CONCLUSIONS: Our findings posed the dynamic pattern of brain parenchymal lesions related to DMVs injury, shedding light on the interactions and chronological roles of various pathological mechanisms.

Association of Rare NOTCH3 Variants With Prevalent and Incident Stroke and Dementia in the General Population.

BACKGROUND: It is uncertain whether rare NOTCH3 variants are associated with stroke and dementia in the general population and whether they lead to alterations in cognitive function. This study aims to determine the associations of rare NOTCH3 variants with prevalent and incident stroke and dementia, as well as cognitive function changes. METHODS AND RESULTS: In the prospective community-based Shunyi Study, a total of 1007 participants were included in the baseline analysis. For the follow-up analysis, 1007 participants were included in the stroke analysis, and 870 participants in the dementia analysis. All participants underwent baseline brain magnetic resonance imaging, carotid ultrasound, and whole exome sequencing. Rare NOTCH3 variants were defined as variants with minor allele frequency <1%. A total of 137 rare NOTCH3 carriers were enrolled in the baseline study. At baseline, rare NOTCH3 variant carriers had higher rates of stroke (8.8% versus 5.6%) and dementia (2.9% versus 0.8%) compared with noncarriers. After adjustment for associated risk factors, the epidermal growth factor-like repeats (EGFr)-involving rare NOTCH3 variants were associated with a higher risk of prevalent stroke (odds ratio [OR], 2.697 [95% CI, 1.266-5.745]; P=0.040) and dementia (OR, 8.498 [95% CI, 1.727-41.812]; P=0.032). After 5 years of follow-up, we did not find that the rare NOTCH3 variants increased the risk of incident stroke and dementia. There was no statistical difference in the change in longitudinal cognitive scale scores. CONCLUSIONS: Rare NOTCH3 EGFr-involving variants are genetic risk factors for stroke and dementia in the general Chinese population.

White matter and gray matter changes related to cognition in community populations.

Objective: Further studies are needed to improve the understanding of the pathological process underlying cognitive impairments. The purpose of this study is to investigate the global and topographic changes of white matter integrity and cortical structure related to cognitive impairments in a community-based population. Methods: A cross-sectional analysis was performed based on 995 subjects (aged 56.8 ± 9.1 years, 34.8% males) from the Shunyi study, a community-dwelling cohort. Cognitive status was accessed by a series of neurocognitive tests including Mini-Mental State Examination (MMSE), Montreal Cognitive Assessment (MoCA), category Verbal Fluency Test (VFT), Digit Span Test (DST), and Trail Making Tests A and B (TMT-A and TMT-B). Structural and diffusional MRI data were acquired. White matter integrity was assessed using fractional anisotropy (FA), mean diffusivity (MD), and peak width of skeletonized mean diffusivity (PSMD). Cortical surface area, thickness, and volume were measured using Freesurfer. Probabilistic tractography was further conducted to track the white matter fibers connecting to the cortical regions related to cognition. General linear models were used to investigate the association between brain structure and cognition. Results: Global mean FA and MD were significantly associated with performances in VFT (FA, ß 0.119, p < 0.001; MD, ß -0.128, p < 0.001). Global cortical surface area, thickness, and volume were not related to cognitive scores. In tract-based spatial statistics analysis, disruptive white matter integrity was related to cognition impairment, mainly in visuomotor processing speed, semantic memory, and executive function (TMT-A and VFT), rather than verbal short-term memory and working memory (DST). In the whole brain vertex-wise analysis, surface area in the left orbitofrontal cortex, right posterior-dorsal part of the cingulate gyrus, and left central sulcus were positively associated with MMSE and MoCA scores, and the association were independent of the connecting white matter tract. Conclusion: Disrupted white matter integrity and regional cortical surface area were related to cognition in community-dwelling populations. The associations of cortical surface area and cognition were independent of the connecting white matter tract.

Pattern of Brain Parenchymal Damage Related to Cerebral Small Vessel Disease in Carriers of Rare NOTCH3 Variants.

BACKGROUND AND OBJECTIVES: Previous studies reported that carriers of rare NOTCH3 variants comprised more than 10% of the general population and are susceptible to a heavy overall burden of cerebral small vessel disease while the injury patterns remain uncovered. This study aimed to investigate the imaging features in relation to rare NOTCH3 variants and the interaction between cortical atrophy and white matter lesions from a longitudinal view, with respect to spatial and dynamic patterns. METHODS: As part of a community-based cohort, we included participants with complete whole-exome sequencing and brain MRI in the baseline analysis. All participants were invited for a 5-year follow-up MRI, and those who did not complete the follow-up were excluded from the longitudinal analysis. NOTCH3 variants with minor allele frequency <1% in all 4 public population databases were defined as rare variants. We used general linear models to compare the volume of white matter hyperintensity (WMH) volume and brain parenchymal fraction between rare NOTCH3 variant carriers and noncarriers. In addition, we compared the WMH probability map and vertex-wise cortex maps at a voxel/vertex-wise level. RESULTS: A total of 1,054 participants were included in baseline analysis (13.56% carried rare NOTCH3 variants), among whom 661 had a follow-up brain MRI (13.76% carried rare NOTCH3 variants). Rare NOTCH3 variant carriers had a heavier white matter hyperintensity burden (1.65 vs 0.85 mL, p = 0.025) and had more extensive WMH distributed in the periventricular areas. We also found that rare NOTCH3 variant carriers were susceptible to worse cortical atrophy (ß = -0.004, SE = 0.002, p = 0.057, adjusted for age and sex). Cortical atrophy of multiple regions in the frontal and parietal lobes was related to white matter hyperintensity progression. DISCUSSION: Individuals with rare NOTCH3 variants have a distinct pattern of brain parenchymal damage related to CSVD. Our findings uncover the important genetic predisposition in age-related cerebral small vessel disease in the general population.

Deep medullary veins are associated with widespread brain structural abnormalities.

Our aim is to investigate the association of cerebral deep medullary veins (DMVs) with white matter microstructural integrity and regional brain atrophy in MRI. In a community-based cohort of 979 participants (mean age 55.4 years), DMVs were identified on susceptibility-weighted imaging. Brain structural measurements including gray matter and hippocampus volumes, as well as diffusion tensor metrics, were evaluated. The mean (SD)number of DMVs was 19.0 (1.7). A fewer number of DMVs was related to lower fractional anisotropy and higher mean diffusivity in multiple voxels on the white matter skeleton (threshold-free cluster enhancement corrected p < 0.05, adjusted for age and sex). Also, fewer DMVs were significantly related to a lower gray matter fraction and a hippocampal fraction (0.10 and 0.11 per DMV, respectively; SE, 0.03 for both; p < 0.001 for both). A significant correlation between DMVs' reduction and cortical atrophy was observed in the bilateral occipital lobes, temporal lobes, hippocampus, and frontal lobes (p < 0.001, adjusted for age, sex, and total intracranial volume). Our results provided evidence that cerebral small venules disease play a role in brain parenchymal lesions and neurodegenerative processes.

Regional Disruption of White Matter Integrity and Network Connectivity Are Related to Cognition.

BACKGROUND: Cognitive impairment is common in the elderly population. Exploring patterns of white matter damage at the microstructural level would give important indications for the underlying mechanisms. OBJECTIVE: To investigate the spatial patterns of white matter microstructure and structural network alternations in relation to different cognition domainsMethods:Participants from the community-based Shunyi Study were included to investigate the association between white matter measurements and cognition cross-sectionally, via both global and local analysis. Cognitive functions were assessed using digit span, trail making test (TMT)-A/B, Fuld object Memory, and 12-Word Philadelphia Verbal Learning Test (PVLT). White matter measurements including fractional anisotropy (FA), mean diffusivity (MD), and structural network parameters were calculated based on diffusion tensor imaging. RESULTS: Of the 943 participants included, the mean (SD) age was 55.8 (9.1) years, and the mean (SD) education level was 6.7 (3.2) years. We found the whole set of cognitive measurements was related to diffused white matter microstructural integrity damage and lower global efficiency. Poor executive functions (TMTA/B complete time) were related to lower FA and higher MD predominantly on the anterior white matter skeleton, while verbal memory loss (PVLT test scores) was related to sub-network dysconnectivity in the midline and the right temporal lobe. CONCLUSION: The anterior brain is dominantly involved in executive dysfunction, while midline and right temporal brain disconnection are more prominent in verbal memory loss. Global and regional disruption of white matter integrity and network connectivity is the anatomical basis of the cognitive impairment in the aging population.

Investigating the Genetic Characteristics of Hippocampal Volume and Plasma ß-Amyloid in a Chinese Community-Dwelling Population.

BACKGROUND AND OBJECTIVES: The genetic characteristics and correlations of hippocampal volume and plasm Aß, probable endophenotypes for dementia, remain to be explored in Chinese community cohort. Using whole-exome sequencing and SNP-array genotyping, we sought to identify rare and common variants and genes influencing these two endophenotypes, and calculate their heritability and genetic correlation. METHODS: Association analyses with both whole-exome sequencing and SNP-array genotyping data were performed for hippocampal volumes and plasm Aß with mixed-effect linear regression model adjusted for sex, age, and total intracranial volume or APOE ε4 while considering familial relatedness. We also performed gene-level analysis for common and gene-burden analysis for rare variants. Heritability and genetic correlation were further examined. RESULTS: Totally 1,261 participants from a Chinese community cohort were included and we identified one gene, PTPRT, for hippocampal volume, with the top significant SNPs by whole genome-wide association study. rs6030076 (P=5.48×10-8, ß=-0.092, SE=0.017) from whole-exome sequencing and rs6030088 (P=8.24×10-9, ß=-105.22 SE=18.09) from SNP-array data, both located in this gene. Gene-burden analysis based on rare mutations detected 6 genes to be significantly associated with Aß. The SNP-based heritability was 0.43±0.13 for hippocampal volume and 0.2-0.3 for plasma Aß. The SNP-based genetic correlation between hippocampal volume and plasma Aß were negative. DISCUSSION: In this study, we identified several SNPs and one gene, PTPRT, which were not reported in previous GWASs, associated with hippocampal volume. Besides, the heritability and the genetic correlation gave an overview of hippocampal volume and plasma Aß. Our findings provide insights into the mechanisms behind the individual variances in these endophenotypes.

Inflammatory biomarkers and cerebral small vessel disease: a community-based cohort study.

BACKGROUND AND PURPOSE: Although inflammation has been proposed to be a candidate risk factor for cerebral small vessel disease (CSVD), previous findings remain largely inconclusive and vary according to disease status and study designs. The present study aimed to investigate possible associations between inflammatory biomarkers and MRI markers of CSVD. METHODS: A group of 15 serum inflammatory biomarkers representing a variety of those putatively involved in the inflammatory cascade was grouped and assessed in a cross-sectional study involving 960 stroke-free subjects. The biomarker panel was grouped as follows: systemic inflammation (high-sensitivity C reactive protein (hsCRP), interleukin 6 and tumour necrosis factor α), endothelial-related inflammation (E-selectin, P-selectin, intercellular adhesion molecule 1, vascular cell adhesion molecule 1 (VCAM-1), CD40 ligand, lipoprotein-associated phospholipase A2, chitinase-3-like-1 protein and total homocysteine (tHCY)) and media-related inflammation (matrix metalloproteinases 2, 3 and 9, and osteopontin). The association(s) between different inflammatory groups and white matter hyperintensity (WMH), lacunes, cerebral microbleeds (CMBs), enlarged perivascular space (PVS) and the number of deep medullary veins (DMVs) were investigated. RESULTS: High levels of serum endothelial-related inflammatory biomarkers were associated with both increased WMH volume (R2=0.435, p=0.015) and the presence of lacunes (R2=0.254, p=0.027). Backward stepwise elimination of individual inflammatory biomarkers for endothelial-related biomarkers revealed that VCAM-1 was significant for WMH (ß=0.063, p=0.005) and tHCY was significant for lacunes (ß=0.069, p<0.001). There was no association between any group of inflammatory biomarkers and CMBs or PVS. Systemic inflammatory biomarkers were associated with fewer DMVs (R2=0.032, p=0.006), and backward stepwise elimination of individual systemic-related inflammatory biomarkers revealed that hsCRP (ß=-0.162, p=0.007) was significant. CONCLUSION: WMH and lacunes were associated with endothelial-related inflammatory biomarkers, and fewer DMVs were associated with systemic inflammation, thus suggesting different underlying inflammatory processes and mechanisms.

Proteomic insights into the photosynthetic divergence between bark and leaf chloroplasts in Salix matsudana.

Bark chloroplasts play important roles in carbon balancing by recycling internal stem CO2 into assimilated carbon. The photosynthetic response of bark chloroplasts to interior stem environments has been studied recently in woody plants. However, the molecular regulatory mechanisms underlying specific characteristics of bark photosynthesis remain unclear. To address this knowledge gap, differences in the structure, photosynthetic activity and protein expression profiles between bark and leaf chloroplasts were investigated in Salix matsudana in this study. Bark chloroplasts exhibited broader and lower grana stacks and higher levels of starch relative to leaf chloroplasts. Concomitantly, decreased oxygen evolution rates and decreased saturated radiation point were observed in bark chloroplasts. Furthermore, a total of 293 differentially expressed proteins (DEPs) were identified in bark and leaf chloroplast profile comparisons. These DEPs were significantly enriched in photosynthesis-related biological processes or Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways associated with photosynthesis. All 116 DEPs within the KEGG pathways associated with photosynthesis light reactions were downregulated in bark chloroplasts, including key proteins responsible for chlorophyll synthesis, light energy harvesting, nonphotochemical quenching, linear electron transport and photophosphorylation. Interestingly, seven upregulated proteins involved in dark reactions were identified in bark chloroplasts that comprised two kinds of malic enzymes typical of C4-type photosynthesis. These results provide comprehensive proteomic evidence to understand the low photochemical capability of bark chloroplasts and suggest that bark chloroplasts might fix CO2 derived from malate decarboxylation.

Arterial Stiffness is Associated with Intracranial Arterial Stenosis other than Dolichoectasia in the General Population.

AIMS: The relationship between central arterial stiffness and aging-related intracranial arteriopathy is not well investigated in the general population. In a population-based study, we investigated arterial stiffness in relation to intracranial atherosclerotic stenosis and intracranial arterial dolichoectasia. METHODS: This study was a cross-sectional analysis on 1,123 subjects (aged 56.0±9.3 years, 37.9% men) of the population-based Shunyi study in China. Arterial stiffness was assessed by measuring brachial-ankle pulse wave velocity (baPWV). Intracranial atherosclerotic stenosis and intracranial arterial dolichoectasia were evaluated via brain magnetic resonance angiography. Multivariate regression models were constructed to investigate the association between baPWV and intracranial large artery diseases. RESULTS: Increased baPWV was significantly associated with higher prevalence of intracranial atherosclerotic stenosis (odds ratio for the highest quartile of baPWV compared with the lowest quartile, 3.66 [95% confidence interval, 1.57- 8.54]), after adjustment for cardiovascular risk factors in multivariate analysis. BaPWV was not associated with the presence of basilar artery dolichoectasia and dilation of basilar artery and internal carotid artery. When the diameters of intracranial arteries were regarded as continuous variables, increased baPWV was inversely related to the internal carotid artery diameter in fully adjusted models (ß±SE, -0.083±0.042, p = 0.047). CONCLUSIONS: This population-based study demonstrates that arterial stiffness was more likely associated with intracranial stenotic arteriopathy other than intracranial dilative arteriopathy.

Metabolic syndrome, intracranial arterial stenosis and cerebral small vessel disease in community-dwelling populations.

BACKGROUND AND PURPOSE: This study aimed to investigate the association of metabolic syndrome (MetS) with both intracranial atherosclerotic stenosis (ICAS) and imaging markers of cerebral small vessel disease (CSVD) in a community-based sample. METHODS: This study included 943 participants (aged 55.6±9.2 years, 36.1% male) from the community-based Shunyi cohort study. MetS was defined according to the joint interim criteria and quantified by the MetS severity Z-score. ICAS was evaluated by brain magnetic resonance angiography. The MRI markers of CSVD, including white matter hyperintensities (WMHs), lacunes, cerebral microbleeds (CMBs) and enlarged perivascular spaces (EPVS), were assessed. Multiple regression models were used to investigate the association of MetS severity Z-score with ICAS and these CSVD markers. RESULTS: We found that risk of ICAS (OR=1.75, 95% CI 1.39 to 2.21, p<0.001) increased consistently with MetS severity. MetS severity was significantly associated with higher risks of WMH volume (ß=0.11, 95% CI 0.01 to 0.20, p=0.02) and lacunes (OR=1.28, 95% CI 1.03 to 1.59, p=0.03) but not the presence of CMBs (OR=0.93, 95% CI 0.74 to 1.16, p=0.51) and PVS severity (EPVS in basal ganglia: OR=0.96, 95% CI 0.84 to 1.09, p=0.51 and EPVS in white matter: OR=1.09, 95% CI 0.96 to 1.23, p=0.21). CONCLUSIONS: Our findings suggest that WMH and lacunes share risk factors with atherosclerosis of the cerebral artery, whereas the impact of glucose and lipid metabolic disorder to CMB or EPVS might be weak.

Arterial Stiffness Is Associated with White Matter Disruption and Cognitive Impairment: A Community-Based Cohort Study.

BACKGROUND: Mechanisms through which arterial stiffness impacts cognitive function are crucial for devising better strategies to prevent cognitive decline. OBJECTIVE: To examine the associations of arterial stiffness with white matter integrity and cognition in community dwellings, and to investigate whether white matter injury was the intermediate of the associations between arterial stiffness and cognition. METHODS: This study was a cross-sectional analysis on 952 subjects (aged 55.5±9.1 years) who underwent diffusion tensor imaging and measurement of brachial-ankle pulse wave velocity (baPWV). Both linear regression and tract-based spatial statistics were used to investigate the association between baPWV and white matter integrity. The association between baPWV and global cognitive function, measured as the mini-mental state examination (MMSE) was evaluated. Mediation analysis was performed to assess the influence of white matter integrity on the association of baPWV with MMSE. RESULTS: Increased baPWV was significantly associated with lower mean global fractional anisotropy (ß= -0.118, p < 0.001), higher mean diffusivity (ß= 0.161, p < 0.001), axial diffusivity (ß= 0.160, p < 0.001), and radial diffusivity (ß= 0.147, p < 0.001) after adjustment of age, sex, and hypertension, which were measures having a direct effect on arterial stiffness and white matter integrity. After adjustment of age, sex, education, apolipoprotein E ɛ4, cardiovascular risk factors, and brain atrophy, we found an association of increased baPWV with worse performance on MMSE (ß= -0.093, p = 0.011). White matter disruption partially mediated the effect of baPWV on MMSE. CONCLUSION: Arterial stiffness is associated with white matter disruption and cognitive decline. Reduced white matter integrity partially explained the effect of arterial stiffness on cognition.