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Sui, B.

Publications and source records attributed to Sui, B..

8 recordsLinked to original sources

Composition of Carotid Plaques Differs Between Chinese and United States Patients: A Histology Study

BackgroundThe clinical manifestations of cerebrovascular disease are known to differ between the Chinese and United States (U.S.) populations as do the plaque features on imaging. ObjectivesThe aim of this study was to investigate and compare the histological features of excised carotid plaques from Chinese and U.S. patients. MethodsCarotid endarterectomy specimens collected from two prospective studies were included. The entire plaque was serially sectioned (10 {micro}m thickness) at 0.5-1 mm intervals. Hematoxylin and eosin staining and Mallorys trichrome staining were performed. The morphology and components of the plaques were measured and compared between the two groups. ResultsA total of 1,152 histological sections from 75 Chinese patients and 1,843 sections from 111 U.S. patients were analyzed. The Chinese group had significantly smaller minimum lumen diameters (median: 1.1 vs. 1.3 mm, p=0.046) and a larger percent wall volume (median: 74% vs. 70%, p=0.018) than the U.S. group. After adjusting for confounding factors, carotid plaques in the Chinese population were more likely to have more lipid pools ({beta}=10.0%, 95%CI: 4.9 to 15.9%), more recent intraplaque hemorrhage (IPH; {beta}=8.4%, 95%CI: 4.5 to 12.7%), and less late IPH ({beta}=-8.2%, 95%CI: -11.3 to -5.4), and fewer fibrous cap disruptions (45% vs. 67%, p=0.061). Chinese plaques were more homogeneous and had a higher percentage of plaques with features of xanthomas than did U.S. plaques (20% vs 2.7%, p<0.001). ConclusionsThe histology of Chinese plaques differs significantly from that of U.S. plaques, suggesting substantial differences in the pathophysiology of atherosclerotic cerebrovascular disease between Chinese and North American populations, which could enhance the gap in racial pathology comparison, indicating a need for a different management approach. Central illustration O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=154 SRC="FIGDIR/small/658993v1_ufig1.gif" ALT="Figure 1"> View larger version (83K): org.highwire.dtl.DTLVardef@14f16corg.highwire.dtl.DTLVardef@f60d66org.highwire.dtl.DTLVardef@1e9a822org.highwire.dtl.DTLVardef@11d7a31_HPS_FORMAT_FIGEXP M_FIG C_FIG

pathology↗

Immunomagneto-activated hepatocyte-specific tissue vesicle profiling reveals message diversification from regenerating liver

Background & AimsThe liver possesses a remarkable regenerative capacity involving intricate intercellular communication, the mechanisms of which remain poorly understood. Extracellular vesicles (EVs) emerge as important messengers in diverse pathophysiological conditions. However, tissue-derived, cell-specific functional EV populations in regeneration have not been robustly investigated. MethodsBulk and single-cell RNA sequencing analyses of the regenerating liver after partial hepatectomy (PHx), ultrastructural examinations of in situ liver tissue EVs (LT-EVs), and nanoscale and proteomic profiling of hepatocyte-derived tissue EVs (Hep-EVs) were integrated. Targeted inhibition of Hep-EV release in vivo was performed via AAV-mediated shRNA knockdown of Rab27a, and Hep-EVs were intravenously infused for therapeutically use. Gross, histological, and immunofluorescent examinations of livers with evaluating in vivo and ex vivo hepatocyte proliferation were conducted. ResultsLT-EVs contribute to the liver regenerative process after PHx, and hepatocytes serve as the major origin of tissue EVs in the regenerating liver. Moreover, Hep-EVs play an indispensable role to orchestrate liver regeneration, which is strengthened to release with proliferative messages identified after PHx. Mechanistically, Hep-EVs from the regenerating liver reciprocally promote hepatocyte proliferation, which are hallmarked by and function based on the Cyclin dependent kinase 1 (Cdk1) activity. Importantly, replenishment of Hep-EVs from the regenerating liver holds translational promise and rescues insufficient liver regeneration. ConclusionsOur study establishes a functional and mechanistic framework that release of regenerative Hep-EVs govern rapid hepatocyte proliferation through cell cycle control, shedding light on investigation of physiological and endogenous tissue EV populations in organ regeneration and therapy.

cell biology↗

Beige adipose tissue-derived extracellular vesicles: a potent metabolic regulator and a novel remedy for nonalcoholic fatty liver disease

Adipose tissue (AT) is an essential metabolic and endocrine organ, which are categorized into the white adipose tissue (WAT) and the brown adipose tissue (BAT), as well as the beige adipose tissue (BeAT) that derives from WAT browning. Notably, extracellular vesicles (EVs), especially tissue-produced EVs, have been recognized to be critical players in multiple physiological and pathophysiological settings and provide efficient strategy for disease treatment. However, little is known about the BeAT-derived EVs (BeEVs). In this study, we induced BeEV formation by cold stimulation and extracted EVs from three kinds of AT via enzyme digestion combined with gradient centrifugation. The isolated BeEVs possess typical morphological, structural and marker characteristics of EVs. Proteomics analysis further demonstrated that the BeEVs hold a distinct protein profile while are enriched with multiple metabolic regulatory proteins. Importantly, systemic injection of BeEVs into mice improved metabolic dysfunction in a nonalcoholic fatty liver disease (NAFLD) model induced by high-fat diet (HFD). Moreover, we demonstrated that the BeEVs alleviated liver steatosis via decreasing the lipogenesis. These findings promote the understanding of AT-EVs and shed light on the isolation, identification and applications of BeEVs as a potent metabolic regulator and novel remedy for metabolic diseases.

cell biology↗

TRIM72 restricts lyssavirus infection by inducing K48-linked ubiquitination and proteasome degradation of the matrix protein

The tripartite motif (TRIM) protein family is the largest subfamily of E3 ubiquitin ligases, playing a crucial role in the antiviral process. In this study, we found that TRIM72, a member of the TRIM protein family, was increased in neuronal cells and mouse brains following rabies lyssavirus (RABV) infection. Over-expression of TRIM72 significantly reduced the viral titer of RABV in neuronal cells and mitigated the pathogenicity of RABV in mice. Furthermore, we found that TRIM72 over-expression effectively prevents the release of RABV. In terms of the mechanism, TRIM72 promotes the K48-linked ubiquitination of RABV Matrix protein (M), leading to the degradation of M through the proteasome pathway. TRIM72 directly interacts with M and the interaction sites were identified and confirmed through TRIM72-M interaction model construction and mutation analysis. Further investigation revealed that the degradation of M induced by TRIM72 was attributed to TRIM72s promotion of ubiquitination at site K195 in M. Importantly, the K195 site was found to be partially conserved among lyssaviruss M proteins, and TRIM72 over-expression induced the degradation of these lyssavirus M proteins. In summary, our study has uncovered a TRIM family protein, TRIM72, that can restrict lyssavirus replication by degrading M, and we have identified a novel ubiquitination site (K195) in lyssavirus M. Author SummaryRabies, caused by lyssaviruses, most often by rabies virus, the most lethal zoonotic disease, is responsible for approximately 59000 human deaths globally each year. Lyssavirus M protein displays an essential role in lyssavirus assembly and budding. Here, we found that TRIM family protein TRIM72 directly interacts with lyssavirus M thereby promoting the K48-linked ubiquitination of M, leading to the degradation of M through the proteasome pathway, restricting lyssavirus release. Moreover, we identified a novel important ubiquitination site (K195) in lyssavirus M. Prior to our study, there had been no reports of a direct interaction between TRIM72 and viral proteins, an antiviral function of TRIM72 was proved in our study. It is possible that TRIM72 interacts and ubiquitinates other viral proteins from various viruses, which warrants further investigation. This research contributes to our understanding of how TRIM72 and other TRIM proteins play a role in defending against viral invasions and may inspire further research in this field.

microbiology↗

Vascular-water-exchange MRI (VEXI) enables the detection of subtle BBB breakdown in Alzheimer's disease without MRI contrast agent

Blood-brain barrier (BBB) impairment is an important pathophysiological process in Alzheimers disease (AD) and a potential biomarker for early diagnosis of AD. However, most current neuroimaging methods assessing BBB function need the injection of exogenous contrast agents (or tracers), which limits the application of these methods in a large population. In this study, we aim to explore the feasibility of vascular water exchange MRI (VEXI), a diffusion-MRI-based method to assess the BBB permeability to water molecules without using a contrast agent, in the detection of the BBB breakdown in AD. We tested VEXI on a 3T MRI scanner on three groups: AD patients (AD group), mild cognitive impairment (MCI) patients due to AD (MCI group), and the age-matched normal cognition subjects (NC group). Interestingly, we find that VEXI can detect the BBB permeability to water molecules increase in MCI and this BBB breakdown happens specifically in the hippocampus. This BBB breakdown gets worse and extends to more brain regions (orbital frontal cortex and thalamus) from MCI group to the AD group. Furthermore, we find that the BBB breakdown of these three regions detected by VEXI is correlated significantly with impairment of respective cognitive domains independent of age, sex and education. These results suggest VEXI is a promising method to assess the BBB breakdown in AD. HighlightsO_LIThe vascular water exchange MRI (VEXI) is a contrast-agent-free method to assess BBB permeability C_LIO_LIBBB breakdown happens specifically in the hippocampus, orbital frontal cortex, and thalamus in AD C_LIO_LIBBB breakdown detected by VEXI is significantly correlated with cognitive dysfunction C_LI

neuroscience↗

A spatial and cellular distribution of neurotropic virus infection in the mouse brain revealed by fMOST and single cell RNA-seq

Neurotropic virus infection can cause serious damage to the central nervous system (CNS) in both human and animals. The complexity of the CNS poses unique challenges to investigate the infection of these viruses in the brain using traditional techniques. In this study, we explore the use of fluorescence micro-optical sectioning tomography (fMOST) and single cell RNA sequencing (scRNA-seq) to map the spatial and cellular distribution of a representative neurotropic virus, rabies virus (RABV), in the whole brain. Mice were inoculated with a lethal dose of recombinant RABV expressing enhanced green fluorescent protein (EGFP) under different infection routes, and a three-dimensional view of the distribution of RABV in the whole mouse brain was obtained using fMOST. Meanwhile, we pinpointed the cellular distribution of RABV by utilizing scRNA-seq. Our fMOST data provide the first evidence that RABV can infect multiple nuclei related to fear independent of different infection routes. More surprisingly, scRNA-seq data indicate that besides neurons RABV can infect macrophages and NK cells in vivo. Collectively, this study draws a comprehensively spatial and cellular map of RABV infection in the mouse brain, providing a novel and insightful strategy to investigate the pathogenesis of neurotropic viruses.

microbiology↗

Apoptotic Extracellular Vesicles (ApoEVs) Safeguard Liver Homeostasis and Regeneration via Assembling an ApoEV-Golgi Organelle

Apoptosis is an integral physiological cell death process that occurs frequently and generates a huge number of apoptotic extracellular vesicles (apoEVs). However, whether apoEVs are necessary for maintaining organ homeostasis remains unclear. Here, we show that circulatory apoEVs engraft in liver and undergo specialized internalization by hepatocytes (HCs) based on surface signature of galactose and N-acetylgalactosamine. Furthermore, apoEVs rescue liver injury in apoptotic-deficient Fas mutant and Caspase-3 knockout mice, which is exerted by restoring the featured hepatic ploidy homeostasis. Surprisingly, apoEVs form a chimeric organelle complex with recipient Golgi apparatus via SNARE-mediated membrane interaction, which consequently facilitates microtubule organization and HC cytokinesis. Notably, through Golgi recovery and ploidy transition, apoEVs contribute to liver regeneration and protect against acute hepatic failure. Collectively, these results identify a previously unrecognized role for apoEVs and the specific mechanisms by which they safeguard liver homeostasis, and suggest the potential of apoEV-based therapy for liver disorders.

cell biology↗

A novel antiviral lncRNA EDAL shields a T309 O-GlcNAcylation site to promote EZH2 degradation

The central nervous system (CNS) is vulnerable for viral infection, yet few host factors in the CNS are known to defend invasion by neurotropic viruses. We report here that multiple neurotropic viruses, including rabies virus (RABV), vesicular stomatitis virus (VSV), Semliki Forest virus (SFV) and herpes simplex virus 1 (HSV-1), elicit the neuronal expression of a host-encoded lncRNA EDAL. EDAL inhibits the replication of these neurotropic viruses in neuronal cells and RABV infection in mouse brains. EDAL binds to the conserved histone methyltransferase enhancer of zest homolog 2 (EZH2) and specifically causes EZH2 degradation via lysosomes, reducing the cellular H3K27me3 level. The antiviral function of EDAL resides in a 56-nt antiviral substructure through which its 18-nt helix-loop intimately contacts multiple EZH2 sites surrounding T309, a known O-GlcNAcylation site. EDAL positively regulate the transcription of Pcp4l1 encoding a 10 kDa peptide, which inhibits the replication of mutiple neurotropic viruses. Our findings proposed a model in which a neuronal lncRNA can exert an effective antiviral function via blocking a specific O-GlcNAcylation that determines EZH2 lysosomal degradation.

microbiology↗