Aortic Lesions Research Articles

Neoagarotetraose Alleviates Atherosclerosis via Modulating Cholesterol and Bile Acid Metabolism in ApoE-/- Mice.

Atherosclerosis is closely associated with metabolic disorders such as cholesterol accumulation, bile acid metabolism, and gut dysbiosis. Neoagarotetraose supplementation has been shown to inhibit obesity and alleviate type 2 diabetes, but its effects on modulating the development of atherosclerosis remain unexplored. Therefore, the present study was conducted to investigate the protective effects and potential mechanisms of neoagarotetraose on high-fat, high-cholesterol diet (HFHCD)-induced atherosclerosis in ApoE-/- mice. The results showed that neoagarotetraose supplementation decreased the atherosclerotic lesion area by 50.1% and the aortic arch lesion size by 80.4% compared to the HFHCD group. Furthermore, neoagarotetraose supplementation led to a significant reduction in hepatic lipid content, particularly non-high-density lipoprotein cholesterol. It also resulted in a substantial increase in total bile acid content in both urine and fecal samples by 3.0-fold and 38.7%, respectively. Moreover, neoagarotetraose supplementation effectively downregulated the intestinal farnesoid X receptor by 35.8% and modulated the expressions of its associated genes in both the liver and intestine. In addition, correlation analysis revealed strong associations between gut microbiota composition and fecal bile acid levels. These findings highlight the role of gut microbiota in neoagarotetraose-mitigating atherosclerosis in HFHCD-fed ApoE-/- mice. This study indicates the potential of neoagarotetraose as a functional dietary supplement for the prevention of atherosclerosis.

MiR-369-3p ameliorates diabetes-associated atherosclerosis by regulating macrophage succinate-GPR91 signaling.

Diabetes leads to dysregulated macrophage immunometabolism, contributing to accelerated atherosclerosis progression. Identifying critical factors to restore metabolic alterations and promote resolution of inflammation remains an unmet goal. MicroRNAs (miRs) orchestrate multiple signaling events in macrophages, yet their therapeutic potential in diabetes-associated atherosclerosis remains unclear. MiRNA profiling revealed significantly lower miR-369-3p expression in aortic intimal lesions from Ldlr-/- mice on a high-fat sucrose containing (HFSC) diet for 12 weeks. miR-369-3p was also reduced in peripheral blood mononuclear cells (PBMCs) from diabetic patients with coronary artery disease (CAD). Cell-type expression profiling showed miR-369-3p enrichment in aortic macrophages. In vitro, oxLDL treatment reduced miR-369-3p expression in mouse bone marrow-derived macrophages (BMDMs). Metabolic profiling in BMDMs revealed that miR-369-3p overexpression blocked the oxLDL-mediated increase in the cellular metabolite succinate and reduced mitochondrial respiration (OXPHOS) and inflammation (lL-1β, TNF-a, IL-6). Mechanistically, miR-369-3p targeted the succinate receptor (GPR91) and alleviated the oxLDL-induced activation of inflammasome signaling pathways. Therapeutic administration of miR-369-3p mimics in HFSC-fed Ldlr-/- mice reduced GPR91 expression in lesional macrophages and diabetes-accelerated atherosclerosis, evident by a decrease in plaque size and pro-inflammatory Ly6Chi monocytes. RNA-seq analyses showed more pro-resolving pathways in plaque macrophages from miR-369-3p treated mice, consistent with an increase in macrophage efferocytosis in lesions. Finally, a GPR91 antagonist attenuated oxLDL-induced inflammation in primary monocytes from human subjects with diabetes. These findings establish a therapeutic role for miR-369-3p in halting diabetes-associated atherosclerosis by regulating GPR91 and macrophage succinate metabolism.

IL-1β Inhibition Partially Negates the Beneficial Effects of Diet-Induced Atherosclerosis Regression in Mice.

Thromboembolic events secondary to rupture or erosion of advanced atherosclerotic lesions is the global leading cause of death. The most common and effective means to reduce these major adverse cardiovascular events, including myocardial infarction and stroke, is aggressive lipid lowering via a combination of drugs and dietary modifications. However, we know little regarding the effects of reducing dietary lipids on the composition and stability of advanced atherosclerotic lesions, the mechanisms that regulate these processes, and what therapeutic approaches might augment the benefits of lipid lowering. Smooth muscle cell lineage-tracing Apoe-/- mice were fed a high-cholesterol Western diet for 18 weeks and then a zero-cholesterol standard laboratory diet for 12 weeks before treating them with an IL (interleukin)-1β or control antibody for 8 weeks. We assessed lesion size and remodeling indices, as well as the cellular composition of aortic and brachiocephalic artery lesions, indices of plaque stability, overall plaque burden, and phenotypic transitions of smooth muscle cell and other lesion cells by smooth muscle cell lineage tracing combined with single-cell RNA sequencing, cytometry by time-of-flight, and immunostaining plus high-resolution confocal microscopic z-stack analysis. Lipid lowering by switching Apoe-/- mice from a Western diet to a standard laboratory diet reduced LDL cholesterol levels by 70% and resulted in multiple beneficial effects including reduced overall aortic plaque burden, as well as reduced intraplaque hemorrhage and necrotic core area. However, contrary to expectations, IL-1β antibody treatment after diet-induced reductions in lipids resulted in multiple detrimental changes including increased plaque burden and brachiocephalic artery lesion size, as well as increasedintraplaque hemorrhage, necrotic core area, and senescence as compared with IgG control antibody-treated mice. Furthermore, IL-1β antibody treatment upregulated neutrophil degranulation pathways but downregulated smooth muscle cell extracellular matrix pathways likely important for the protective fibrous cap. Taken together, IL-1β appears to be required for the maintenance of standard laboratory diet-induced reductions in plaque burden and increases in multiple indices of plaque stability.

A systematic review of blunt abdominal aortic injury and analysis of predictors of death.

At present, research on blunt abdominal aortic injury (BAAI) is limited, with the majority being case reports. Consequently, there is a significant knowledge gap concerning this condition. To address this, we conducted a systematic review by extensively searching major databases. We included all literature that provided individual (non-identifiable) data on BAAI patients, irrespective of the study design. Furthermore, we undertook regression analyses to identify predictors of death after BAAI. The search yielded 2,099 results, leading to the inclusion of 102 case reports and one conference abstract. Using the Joanna Briggs Institute (JBI) checklist for assessment, all studies were deemed of medium to high quality. In total, 133 patients were included, with a median age of 34 years, and 73.7% being male. The predominant clinical manifestation was pain, reported in 65.6% of patients. The most frequently observed aortic lesion severity was grade A (intimal tear or intramural hematoma) at 46.9%, and the most common lesion location was zone III (infrarenal aorta) in 88.3% of cases. The overall mortality after BAAI was 15.3%. Multivariate regression analyses revealed the following predictors of death after BAAI: lower limb ischemia (relative risk [RR] = 7.137, 95% confidence interval [CI] 1.154 - 44.161), cardiopulmonary arrest (RR = 10.250, 95% CI 1.452 - 72.344), and injuries to body parts other than the abdomen and lumbar spine (RR = 2.593, 95% CI 1.189 - 5.655). In conclusion, this review provides a detailed quantitative summary of BAAI's clinical manifestations, diagnosis, treatment, and prognosis, emphasizing its high mortality rate and identifying three critical variables as predictors of death.

Abstract 3078: Free Fatty Acid Receptor 4: An Emerging Target To Reduce Atherosclerosis

Free fatty acid receptor 4 (FFAR4) has recently emerged as a target for preventing CVD through its ability to reduce macrophage foam cell formation and inflammation. We have shown that activation of FFAR4 by synthetic agonists decreases foam cell formation, whereas deficiency of FFAR4 increases foam cell formation. Building on these data, we hypothesized that FFAR4 would protect against atherosclerotic plaque formation in vivo . To test this hypothesis, we generated global FFAR4 knockout mice on an apoE-deficient background. Male and female apoE/FFAR4 double knockout mice (n=20) and their apoE knockout controls (n=20) were fed a Western diet (42% calories from fat and 0.2% cholesterol) for 16 weeks. We collected weekly body weights and fasting plasma samples from mice at 0, 8, and 16 weeks to measure triglyceride and cholesterol levels. At the end of the 16-week study, atherosclerotic plaque severity was determined by analyzing the aortic sinus lesion area of the heart and the en-face lesion area of the aortic arch. In both the male and female mice, we observed no differences in weekly body weights or lipid levels between the apoE knockout and apoE/FFAR4 double knockout mice. In our first cohort of male mice (n=10), the two genotypes showed no difference in the aortic sinus lesion area. However, male apoE/FFAR4 double knockout mice had a statistically significant (p=0.039) 1.4-fold increase in total aortic arch lesion area compared to FFAR4-deficient mice. While female mice (n=9) showed no differences in atherosclerotic plaque in the aortic sinus and aortic arch between the two genotypes, they did present with 1.7-fold (p=0.002) and 2-fold increases (p=0.009) in aortic sinus lesion area and aortic arch lesion area, respectively, as compared to male mice. Based on analysis of an initial set of mice, our data support a protective role for FFAR4 in the development of atherosclerotic plaque formation in male mice, and our findings may have uncovered a new therapeutic target against atherosclerosis.

Abstract 3134: Integrated Multi-Omics Profiling Reveals Neutrophil Extracellular Traps Promote Aortic Dissection

Background: Negative aortic remodeling increases the risk of aorta-related adverse events (AAEs) after thoracic endovascular aortic repair (TEVAR) for patients with aortic dissection (AD). Research Questions and Aims: It is worth investigating prognostic indicators to streamline the identification of individuals at elevated risk for postoperative AAEs, and therapeutic targets to optimize the efficacy of TEVAR. Methods: We performed single-cell transcriptomic and proteomic profiling of aortic lesions and peripheral blood samples, respectively. We then integrated single-cell with publicly accessible bulk data to identify phenotype-relevant subpopulations. We further confirmed the results in human plasma samples and in mouse models. The Cox regression analysis were used to identify independent risk factors. Results: Integrated multi-omics analysis identified a highly phenotype-associated and disease-relevant macrophage subset, which closely interacted with neutrophil via CXCL3/CXCR2 axis, and promoted neutrophil extracellular traps (NETs) within aortic lesion. Likewise, increased NETs formation is a defining feature of systemic immunity of AD, with an expansion of inflammatory cytokines in the peripheral blood. Furthermore, we demonstrated that in a prospective cohort of 115 patients with a median follow-up of 13 months, the level of citrullinated histone H3 (CitH3), a NETs marker, could serve as a risk factor for the occurrence of AAEs following TEVAR (HR 8.78, p < .001). The CitH3 level, determined at a cut-off value of 6.9 ng/ml, predicted the postoperative AAEs with a sensitivity and specificity of 0.6 and 0.9, respectively, and an area under the curve of 0.75. In addition, inhibiting NETs formation through the blockade of CitH3 alleviated the progression and rupture of AD in mice. Conclusions: The multi-omics profiling reveals highly disease-relevant macrophage subpopulation, which promotes NETs formation and inflammation infiltration in the development of AD. Increased NETs formation is a defining feature of both aortic lesion and peripheral blood of patients with AD. CitH3 could facilitate the risk stratification and prognostic evaluation, and might serve as potential therapeutic targets of patients with AD.

Aortic valve repair surgery: a historical review, current analysis, and future prospects

Aortic valve repair surgery is an ancient surgical approach. It is ancient in the sense that it emerged alongside aortic valve replacement surgery, but was gradually abandoned due to suboptimal outcomes. Currently, aortic valve replacement surgery has become the preferred method for treating patients with aortic valve dysfunction, with or without aortic root lesions. However, due to the risks of prosthetic valve deterioration and anticoagulation-related complications, aortic valve repair surgery has re-emerged as an attractive treatment option, avoiding the long-term risks associated with prosthetic valves. However, it comes with the risk of recurrence of valve regurgitation. Remodeling and reimplantation are milestones in aortic valve repair, reducing the risk of aortic regurgitation. The concept of functional anatomy of the aortic root and the mechanism of aortic regurgitation lay the theoretical foundation for modern aortic valve repair. Aortic valve repair has become a comprehensive repair strategy that involves the basal ring, sinus, sino-tubular junction, and aortic lobes. The long-term survival rate is close to that of the normal population, and the valvular-related reintervention rate is comparable to that of valve replacement. Aortic valve repair is gradually becoming a novel alternative treatment for patients with aortic valve insufficiency, with or without aortic root lesions.

Abstract 1052: Sex Specific Effects Of Zbp1 Deficiency In Mouse Lesion Necrotic Core

We previously fine mapped a mouse atherosclerosis susceptibility locus on chr 2 via an intercross between AKR/J (atherosclerosis resistant) and DBA/2J (atherosclerosis sensitive) strains on the apoE-deficient background. The Zbp1 gene, encoding Z-DNA binding protein 1, is one of only 3 protein coding genes in the fine mapped locus. Prior mouse aorta single cell RNAseq shows Zbp1 expression in monocytes and macrophages > endothelial cells and fibroblasts. The ZBP1 protein plays a role in non-canonical necroptosis and inflammatory signaling. There are 2 mouse Zbp1 mRNA splice isoforms, long and short, which respectively generate a full-length protein and a C-terminal truncated isoform that is missing the RHIM domains required for necroptosis activity. Our prior RNAseq found ~2-fold higher Zbp1 expression in DBA/2 vs. AKR bone marrow macrophages (p=0.002), with a short to long isoform ratio of about 2.5. To determine if Zbp1 is an atherosclerosis modifier gene, we treated wildtype (WT) and Zbp1 knockout (K0) female and male mice at 6 weeks of age, both on the C57BL/6J background, with LDLr antisense oligos weekly for 16 weeks while feeding a western-type diet. Upon sacrifice at 22 weeks of age, body weight, liver weight, total cholesterol, and HDL-C were significantly reduced in KO vs WT male, but not female, mice (p= 0.005, 0.0003, 0.007, and 0.002, respectively (Figure). In both male and female mice, there were non-significant trends for reduced aortic root lesion area in KO vs. WT mice. The median necrotic lesion area was decreased in KO vs. WT females by 55%, but due to variation this was not significant. In males, median necrotic area was decreased by 83% (p=0.02, Figure). The % necrotic lesion area was decreased by 32% in female (not significant) and 67% in male (p=0.009) KO vs. WT mice (Figure). Thus, Zpb1 appears to be an atherosclerosis modifier gene that may function by increasing lesion necrosis, concordant with its known role in non-canonical necroptosis.

Abstract 3075: Effect Of Inhaled Benzene Exposure On Atherogenesis

Background: Benzene is a ubiquitous environmental pollutant generated by a variety of natural and anthropological sources. It is a known carcinogen and hematopoietic toxin; however, little is known about benzene's potential atherogenicity. Hypothesis: Inhaled benzene induces atherogenesis by increasing vascular inflammation in LDL receptor Knockout (LDLR-KO) mice. Methods: Male LDLR-KO mice were exposed to HEPA-filtered air or benzene (1 ppm, 6h/day, 5days/week) for 24 weeks. For the last 12 weeks of exposure, the mice were maintained on a western diet. The single nuclei RNA sequencing (snRNAseq) of aortae was performed at Novogene. In an independent experiment, male ApoE-KO mice were maintained on a western diet for 12 weeks and then exposed to benzene for 2 weeks. Cytometry by time of flight (CyTOF) analysis was used for the plaque immunophenotyping. For in vitro experiments, splenic naïve T cells were exposed to 1 μM of hydroquinone (HQ) for 24 hours, and intracellular ROR-gamma levels were measured by flow cytometry. Results: Benzene inhalation increased the aortic valve lesion area by more than 25% (P<0.05) in LDLR-KO mice. Using snRNAseq, eleven major cell types were detected, including T cells and vascular smooth muscle cells (VSMC). Benzene increased the number of T cells by 2.5-fold, proliferating T-cells by 5.8-fold, and VSMC by 1.6-fold, suggesting increased cellularity and reduced plaque stability. In addition, benzene upregulated Th17 polarization marker Rorc and negative regulators of apoptosis Rag1 and Bcl11b while significantly attenuating the expression of proliferation inhibitor Ms4a4b in T cells. In VSMC, benzene downregulated extracellular matrix organization genes and upregulated platelet degranulation pathways. CyTOF analysis of the plaques of ApoE-KO mice showed that even short-term benzene exposure increased T-cell abundance in pre-existing lesions. Polarization of T cells into Th17 was confirmed by HQ-dependent upregulation of ROR-gamma in vitro . Conclusion: Our data suggest that inhaled benzene exposure compromises plaque cellularity and stability by facilitating T-cell proliferation and polarization, which coincides with the degradation of smooth muscle extracellular matrix and platelet activation.

Abstract 2052: Macrophage-specific Ripk1 Knockdown Reduces Macrophage Inflammation And Atherosclerosis Progression In Ldlr -/- Mice.

Background: Chronic activation of the innate immune system drives inflammation and contributes to atherosclerosis. Pro-inflammatory agents (oxidised LDL, IL-1β) drive lesional inflammation and development, whereas anti-inflammatory agents (IL-10, HDL, Apolipoprotein-AI), promote an anti-inflammatory milieu and resolution. RIPK1 (Receptor interacting protein kinase 1) is a master regulatory gene that decides whether a cell undergoes inflammation, apoptosis and/or necroptosis, depending on its phosphorylation or ubiquitination status. We have previously observed that RIPK1 gene expression is increased in both endothelial cells and macrophages in early atherosclerotic lesions (Karunakaran et al, Circulation 2022). Here, we seek to determine whether macrophage-specific RIPK1 contributes to atherosclerosis. Methods: Given that Ripk1 -/- mice are lethal, we performed bone marrow (BM) transplants of Ripk1 +/- and wild-type (wt) littermate BM into female and male Ldlr -/- mice (n=8-12/grp) and mice were fed a western diet for 12-16 wks. In vitro experiments were performed in BM derived macrophages from wt and Ripk1 +/- mice. Results: Ldlr -/- mice recipient of Ripk1 +/- BM and western diet feeding for 12 or 16 wk had a marked reduction in aortic sinus lesion area (68.9% and 49.7% respectively, p<0.05) compared to their wt controls. Preliminary analysis show that there is a reduction in lesional macrophage area in Ripk1 +/- BM recipient Ldlr -/- mice relative to control (0.02±0.01 vs 0.01±0.006mm, p<0.01), suggesting that macrophage infiltration was reduced. Interestingly, anti-inflammatory agents, including recombinant IL10, IL13 (both 100ng/ml), Apolipoprotein-AI and discoidal HDL (both 500ug/mL) markedly reduced macrophage Ripk1 expression in vitro (by ~50%, p<0.05), likely reducing Ripk1-dependent inflammation and promoting an anti-inflammatory milieu. Current mechanistic studies are investigating the transcriptional regulator, STAT3, as a key regulator of Ripk1 expression. Conclusion: We identified macrophage-RIPK1 as a central driver of atherosclerosis. These timely studies highlight the therapeutic potential of dampening Ripk1 overexpression, as opposed to the detrimental abolishment of Ripk1, in treating atherosclerosis.

Abstract 2060: Hv1 Contributes To Atherosclerosis

Atherosclerosis is a complex process that involves the interaction between oxidized low-density lipoprotein (oxLDL) and macrophage. It is an inflammatory disease of the large artery driven by macrophage activation and infiltration. Through scavenger receptors, macrophages can uptake oxLDL and other lipids, leading to foam cell formation and the progression of atherosclerosis. Hv1 proton channel is highly expressed in phagocytes and promotes NADPH oxidase-derived ROS (reactive oxygen species) production. So far, most of the research on Hv1 has been focused on immune, reproductive, and neurological diseases. However, the role of Hv1 in cardiovascular diseases, such as arteriosclerosis, remains unclear. To explore the potential roles of Hv1 in atherosclerosis, we detected the expression of Hv1 in atherosclerotic lesions. It was shown that Hv1 is abundantly expressed in human and murine atherosclerotic lesions and highly expressed in macrophages in the aortic root lesions. In addition, Hv1 knockout mice fed with a high-fat western diet exhibit remarkably decreased atherosclerotic plaques compared with control mice. Moreover, deficiency of Hv1 in macrophages impedes macrophage phagocytosis and foam cell formation essential for atherosclerosis development, and Hv1 enhances macrophage ROS production associated with the progression of atherosclerosis. Our results suggested that Hv1 is a pro-atherosclerotic factor and contributes to the pathogenesis of atherosclerosis. The research identified a new function of the Hv1 channel in human diseases and may present a novel target against atherosclerosis and atherosclerosis-related diseases.

Abstract 3047: Extracellular Vesicles Produced By IL4-polarized Human Macrophages Suppress Atherosclerosis By Reprograming Ly6c hi Monocytes

Introduction: Extracellular vesicles (EVs) produced by IL4-polarized macrophages (Mφ) suppress inflammation by communicating microRNA-controlled immunometabolic signaling to recipient immune cells and adipocytes. However, detailed cellular and molecular pathways responsible for these effects remain incompletely understood. Objectives: Examine transcriptional responses sensitive to IL4-polarized Mφ EVs among circulating Ly6C hi monocytes derived from mice with hyperlipidemia. Methods/Approach: EVs were produced by culturing THP1 macrophages with human IL4, and purified using cushioned-density gradient ultracentrifugation. Twenty-week old male LDL-receptor deficient mice fed high-fat diet for 16 weeks were treated to a 6-week course of 3-weekly intraperitoneal infusions of 10e 10 THP1-IL4 EVs or sham. Circulating Ly6C hi monocytes were collected using a cell sorter and RNA was examined using nanoString nCounter inflammatory and metabolic pathway panels. Plasma cytokines were detected with a V-Plex MesoScale assay, while atherosclerosis was assessed by detecting myeloid cell subsets in enzymatically-digested aortae and oil red O positive lesions in the aortic root. Results: THP1-IL4 EVs caused profound transcriptional reprogramming among Ly6C hi monocytes, resulting in reduced signaling pathways controlled by MAPK, PI3K, TLR and inflammasomes. We identified reduced levels of Casp-1, Nlrp1a, as well as Aim2, all recognized to drive atherosclerosis including in JAK2 vf clonal hematopoiesis. Furthermore, THP1-IL4 EVs upregulated metabolic pathways involved in arginine metabolism, IDH1/2 activity, redox stress control, nucleotide salvage, fatty acid oxidation and mitochondrial respiration. In contrast they reduced pathways involved in glucose transport, hypoxia, KEAP-NRF2 pathway and tryptophan metabolism. Control of these pathways in Ly6C hi monocytes contributed to reduced levels of IL-1β, IL-6, IFNγ and TNFα in plasma, as well as CD45 + aortic myeloid cells and oil red O positive aortic lesions. Conclusions: IL4-polarized Mφ EVs suppress atherosclerosis by communicating profound transcriptional reprogramming to Ly6C hi monocytes. Ongoing studies examine their capacity to drive atherosclerosis regression.

Spatiotemporal ATF3 Expression Determines VSMC Fate in Abdominal Aortic Aneurysm.

Abdominal aortic aneurysm (AAA) is a catastrophic disease with little effective therapy, likely due to the limited understanding of the mechanisms underlying AAA development and progression. ATF3 (activating transcription factor 3) has been increasingly recognized as a key regulator of cardiovascular diseases. However, the role of ATF3 in AAA development and progression remains elusive. Genome-wide RNA sequencing analysis was performed on the aorta isolated from saline or Ang II (angiotensin II)-induced AAA mice, and ATF3 was identified as the potential key gene for AAA development. To examine the role of ATF3 in AAA development, vascular smooth muscle cell-specific ATF3 knockdown or overexpressed mice by recombinant adeno-associated virus serotype 9 vectors carrying ATF3, or shRNA-ATF3 with SM22α (smooth muscle protein 22-α) promoter were used in Ang II-induced AAA mice. In human and murine vascular smooth muscle cells, gain or loss of function experiments were performed to investigate the role of ATF3 in vascular smooth muscle cell proliferation and apoptosis. In both Ang II-induced AAA mice and patients with AAA, the expression of ATF3 was reduced in aneurysm tissues but increased in aortic lesion tissues. The deficiency of ATF3 in vascular smooth muscle cell promoted AAA formation in Ang II-induced AAA mice. PDGFRB (platelet-derived growth factor receptor β) was identified as the target of ATF3, which mediated vascular smooth muscle cell proliferation in response to TNF-alpha (tumor necrosis factor-α) at the early stage of AAA. ATF3 suppressed the mitochondria-dependent apoptosis at the advanced stage by upregulating its direct target BCL2. Our chromatin immunoprecipitation results also demonstrated that the recruitment of NFκB1 and P300/BAF/H3K27ac complex to the ATF3 promoter induces ATF3 transcription via enhancer activation. NFKB1 inhibitor (andrographolide) inhibits the expression of ATF3 by blocking the recruiters NFKB1 and ATF3-enhancer to the ATF3-promoter region, ultimately leading to AAA development. Our results demonstrate a previously unrecognized role of ATF3 in AAA development and progression, and ATF3 may serve as a novel therapeutic and prognostic marker for AAA.

Recombinant human proteoglycan 4 lowers inflammation and atherosclerosis susceptibility in female low-density lipoprotein receptor knockout mice.

Recombinant human proteoglycan 4 (rhPRG4) is a macromolecular mucin-like glycoprotein that is classically studied as a lubricant within eyes and joints. Given that endogenously produced PRG4 is present within atherosclerotic lesions and genetic PRG4 deficiency increases atherosclerosis susceptibility in mice, in the current study we investigated the anti-atherogenic potential of chronic rhPRG4 treatment. Female low-density lipoprotein receptor knockout mice were fed an atherogenic Western-type diet for 6 weeks and injected three times per week intraperitoneally with 0.5mg rhPRG4 or PBS as control. Treatment with rhPRG4 was associated with a small decrease in plasma-free cholesterol levels, without a change in cholesteryl ester levels. A marked increase in the number of peritoneal foam cells was detected in response to the peritoneal rhPRG4 administration, which could be attributed to elevated peritoneal leukocyte MSR1 expression levels. However, rhPRG4-treated mice exhibited significantly smaller aortic root lesions of 278 ± 21 × 103μm2 compared with 339 ± 15 × 103μm2 in the aortic root of control mice. The overall decreased atherosclerosis susceptibility coincided with a shift in the monocyte and macrophage polarization states towards the patrolling and anti-inflammatory M2-like phenotypes, respectively. Furthermore, rhPRG4 treatment significantly reduced macrophage gene expression levels as well as plasma protein levels of the pro-inflammatory/pro-atherogenic cytokine TNF-alpha. In conclusion, we have shown that peritoneal administration and subsequent systemic exposure to rhPRG4 beneficially impacts the inflammatory state and reduces atherosclerosis susceptibility in mice. Our findings highlight that PRG4 is not only a lubricant but also acts as an anti-inflammatory agent. KEY POINTS: Endogenously produced proteoglycan 4 is found in atherosclerotic lesions and its genetic deficiency in mice is associated with enhanced atherosclerosis susceptibility. In this study we investigated the anti-atherogenic potential of chronic treatment with recombinant human PRG4 in hypercholesterolaemic female low-density lipoprotein receptor knockout mice. We show that recombinant human PRG4 stimulates macrophage foam cell formation, but also dampens the pro-inflammatory state of monocyte/macrophages, eventually leading to a significant reduction in plasma TNF-alpha levels and a lowered atherosclerosis susceptibility. Our findings highlight that peritoneal recombinant human PRG4 treatment can execute effects both locally and systemically and suggest that it will be of interest to study whether rhPRG4 treatment is also able to inhibit the progression and/or induce regression of previously established atherosclerotic lesions.

Role of macrophage polarization in periodontitis promoting atherosclerosis.

Periodontitis is a chronic inflammatory destructive disease occurring in periodontal supporting tissues. Atherosclerosis(AS) is one of the most common cardiovascular diseases. Periodontitis can promote the development and progression of AS. Macrophage polarization is closely related to the developmentandprogression of the above two diseases, respectively. The purpose of this animal study was to evaluate the effect of periodontitis on aortic lesions in atherosclerotic mice and the role of macrophage polarization in this process. 45 ApoE-/-male mice were randomly divided into three groups: control (NC), atherosclerosis (AS), and atherosclerosis with periodontitis (AS + PD). Micro CT, serological testing and pathological testing(hematoxylin-eosin staining, oil red O staining and Masson staining) were used for Evaluate the modeling situation. Immunohistochemistry(IHC) and immunofluorescence(IF) were performed to evaluate macrophage content and macrophage polarization in plaques. Cytokines associated with macrophage polarization were analyzed using quantitative real-time polymerase chain reaction(qRT-PCR) and enzyme-linked immunosorbent assay(Elisa). The expression of macrophages in plaques was sequentially elevated in the NC, AS, and AS + PD groups(P < 0.001). The expression of M1 and M1-related cytokines showed the same trend(P < 0.05). The expression of M2 and M2-related cytokines showed the opposite trend(P < 0.05). The rate of M1/M2 showed that AS + PD > AS > NC. Our preliminary data support that experimental periodontitis can increase the content of macrophage in aortic plaques to exacerbate AS. Meanwhile, experimental periodontitis can increase M1 macrophages, and decrease M2 macrophages, increasing M1/M2 in the plaque.

Left Ventricle Myocardial Work Correlated with Functional Capacity in Severe Rheumatic Mitral Stenosis with Preserved Left Ventricular Ejection Fraction.

Functional capacity is reduced in mitral stenosis (MS) patients. Previous studies showed a correlation between left atrial strain and functional capacity in this population. However, currently, no left ventricle (LV) echocardiographic parameters were associated with functional capacity in patients with MS. Noninvasive LV pressure-strain loop analysis is a new echocardiographic method for evaluating LV function, integrating longitudinal strain from speckle-tracking analysis and noninvasively measured blood pressure to estimate myocardial work (MW) that overcomes the preload-dependent characteristics conventional parameters by integrating afterload. This study aimed to evaluate the association between MW and functional capacity measured using exercise tests in patients with severe MS and preserved LV ejection fraction (LVEF). Adult patients with symptomatic severe rheumatic MS (mitral valve area <1.5 cm2), and preserved LVEF (>50%) and sinus rhythm who underwent echocardiography and exercise stress test in our hospital from 2019 to 2021 were included. Exclusion criteria were suboptimal image quality for myocardial deformation analysis, significant mitral regurgitation or aortic valve lesions, coronary artery disease, intracardiac shunt, and atrial fibrillation. Standard echocardiographic parameters were measured, and all MW parameters were included. Exercise treadmill testing was performed using the modified Bruce protocol. A total of 33 individuals with isolated severe rheumatic MS in sinus rhythm (age 39.8 ± 9.8 years) were included in the study. Patients with severe isolated MS showed significantly impaired LV-global longitudinal strain values compared to normal reference values. Furthermore, patients with severe MS showed significantly lower values of global work index, global constructive work, and efficiency compared to normal values and higher wasted work. Global work efficiency was significantly correlated to the duration of exercise (P = 0.025, Pearson's r = 0.389). In stable patients with isolated severe mitral stenosis, MW efficiency significantly correlated with functional capacity measured objectively through exercise testing.

Minimally Invasive Approach versus Sternotomy for Bentall Procedure: A Single-Center Experience

Background. The need for minimally invasive Bentall surgery for the treatment of aortic lesions with aortic insufficiency is increasing; however, comparative studies on the safety of the minimally invasive Bentall procedure and sternotomy Bentall procedure are lacking. Methods. Clinical data of 56 patients who underwent the Bentall procedure performed by the same surgical team at our center between December 2018 and December 2021 were retrospectively analyzed and followed up for 6 months after discharge. After dividing the patients into a right anterior chest minimally invasive Bentall surgery (RAT-Bentall) group (n = 13) and a conventional sternotomy Bentall surgery (C-Bentall) group (n = 43), intraoperative and early postoperative clinical data and echocardiography at 6 months after discharge were compared. Results. Compared with the C-Bentall group, the RAT-Bentall group had a lower postoperative visual analogue scale (VAS) pain score [(3.00 ± 2.08) VS (5.77 ± 1.84), P&lt;0.001] and a shorter CSICU hospital stay [(1.90 ± 0.52) VS (2.51 ± 1.58) d, P&lt;0.001] and postoperative hospital stay [(7.62 ± 1.81) VS (10.42 ± 2.45) d, P=0.035]. The incidence of postoperative complications and echocardiographic at 6-month follow-up after discharge was not statistically different between the two groups. Conclusion. The RAT-Bentall procedure is safe and effective. Compared with the sternotomy Bentall procedure, it can reduce postoperative pain as well as patients’ CSICU and postoperative hospital stay. Therefore, this technology is worth promoting and applying.

Image fusion guidance for left subclavian artery in situ fenestration during thoracic endovascular repair.

To evaluate the feasibility and clinical benefit of utilizing image fusion for thoracic endovascular repair (TEVAR) with in situ fenestration (ISF-TEVAR). Between January 2020 and December 2020, we prospectively collected 18 consecutive cases with complex thoracic aortic lesions who underwent image fusion guided ISF-TEVAR. As a control group, 18 patients were collected from historical medical records from June 2019 to December 2019. The fusion group involved the use of 3D fusion of CTA and fluoroscopic images for real-time 3D guidance, and the control group involved the use of only regular fluoroscopic images for guidance. The total contrast medium volume, hand-injected contrast medium volume, overall operative time, radiation dose and fluoroscopy time were compared between the two groups. Accuracy was measured based on preoperative CTA and intraoperative digital subtraction angiography. 3D fusion imaging guidance was successfully implemented in all patients in the fusion group. Hand-injected contrast medium volume and overall operative time were significantly lower in the fusion group than in the control group (p = .028 and p = .011). Compared with the control group, the fusion group showed a significant reduction in time and radiation dose-area product (DAP) for fluoroscopy (p = .004 and p = .010). No significant differences in total radiation dose (DAP) or total contrast medium volume were observed (p = .079 and p = .443). Full accuracy was achieved in 8 cases (44%), with a mean deviation of 2.61mm ± 3.1 (range 0.0-8.4mm). 3D image fusion for ISF-TEVAR was associated with a significant reduction in hand-injected contrast medium, time and radiation exposure for fluoroscopy and overall operative time. The image fusion guidance showed potential clinical benefits towards improved treatment safety and accuracy for complex thoracic endovascular interventions.

Coral reef aorta: a rare form of obstruction of the ascending aorta in adolescent with aortopathy- case report

BackgroundSupra aortic obstruction in children is uncommon and is seen in certain unique conditions. While intraluminal obstruction due to heavy calcification is seen in older populations, it is not described in pediatric populations. The coral reef aorta is a rare and distinct calcifying disease causing luminal obstruction of the suprarenal aorta in adults. The definition of this diagnosis relies entirely on the unique aspects and consistency of the lesions, which are rock-hard, irregular, gritty plaques with a white luminal surface resembling a coral reef. However, no such case has been described in children.Case presentationWe present an adolescent boy who presented with a heavily calcified ascending aortic lesion associated with aortopathy and hypertension, 12 years after an aortic coarctation repair. The investigations included echocardiography, magnetic resonance and computer-tomographic imaging. A 3-D model was printed in order to visualize and plan surgical steps in advance for safe placement of clamps and defining the extent of resection. In addition, it provided an idea about tissue quality, thickness, spatial relationship, and orientation in relation to surrounding structures. Successful resection and replacement of the diseased segment of the aorta were achieved on cardiopulmonary bypass support. Post-operative recovery was uneventful, and at 6-month follow-up, the patient is doing well. In this report, various aspects of such lesions have been discussed, including clinical presentations, complications, planning and conduct of a safe cardiopulmonary bypass, and precautions during surgery for a successful outcome.ConclusionComplicated obstructive aortic lesions in children require careful assessment, appropriate advanced imaging, and the use of 3-D printing technology in order to plan and perform safe and effective surgical management. The etiology of severe calcified aorta in children may be related to metabolic factors, previous surgery, use of a homograft, or an inflammatory process. However, it has yet to be proven.

Abstract TP257: Atherogenic Dyslipidemia Advances Crucially the Aortic Complicated Lesion in Cryptogenic Stroke

Background and purpose: The aortic complicated lesion (ACL) is a notable embolic source of cryptogenic stroke (CS) observed in 10-60 % of patients. Although the antithrombotic and statin therapy are certainly effective, the recurrence of aortogenic stroke is not rare. Atherogenic dyslipidemia (AD) is regarded as the significant residual risk of cardiovascular diseases even under the statin remedy and characterized by low high-density lipoprotein (HDL) and high triglyceride (TG). In the present study, we aimed to clarify the underlying association between ACL and AD. Methods: Clinical data of CS patients admitted between April 2014 and December 2016 in Japanese 8 institutes and underwent transesophageal echocardiography (TEE) were analyzed in the present study. Low HDL was defined as ≤ 40 mg/dl and high TG was defined as ≥ 150 mg/dl in the fasting condition, respectively. Furthermore, AD must satisfy both cut-off values. Based on these criteria, patients were divided into 4 groups as AD group, HDL group, TG group, and non-AD group to compare the clinical features. Results: Of 664 CS patients, 68 (57 men, 68.6 ± 11.1 years) met the criteria of AD (AD group), and 108 (90 men, 68.5 ±13.7 years) fulfilled the low HDL only (HDL group), 115 (76 men, 66.9 ± 11.7 years) merely met the high TG (TG group), 373 (223 men, 69.4 ± 13.1 years) satisfied the neither (non-AD group). In a univariate analysis, ACL in arch revealed with TEE was significantly more frequent in AD group (55.9 vs 38.0 vs 39.1 vs 33.8 %, p=0.007). In a multiple regression analysis, male (OR 2.57, 95%CI 1.23-5.38, p=0.012), body mass index (unit OR 1.16, 95%CI 1.08-1.25, p&lt;0.001), diabetes (OR 2.52, 95%CI 1.41-4.53, p=0.002), ACL in arch (OR 2.12, 95%CI 1.19-3.80, p=0.011) were independently, and past history of stroke (OR 0.35, 95%CI 0.14-0.90, p=0.030) was inversely associated with AD group. Conclusions: Although the previous study exhibited that AD was predominantly associated with intracranial stenosis in atherothrombotic brain infarction, AD was also crucially related to ACL in CS in the present study. Concerning the aortogenic stroke, more intensive and pleiotropic lipid-lowering therapy would be efficacious for further treatment.