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Rupture of aortic aneurysm and dissection (AAD) remains a leading cause of death. Progressive smooth muscle cell (SMC) loss is a crucial feature of AAD that contributes to aortic dysfunction and degeneration, leading to aortic aneurysm, dissection, and, ultimately, rupture. Understanding the molecular mechanisms of SMC loss and identifying pathways that promote SMC death in AAD are critical for developing an effective pharmacologic therapy to prevent aortic destruction and disease progression. Cell death is controlled by programmed cell death pathways, including apoptosis, necroptosis, pyroptosis, and ferroptosis. Although these pathways share common stimuli and triggers, each type of programmed cell death has unique features and activation pathways. A growing body of evidence supports a critical role for programmed cell death in the pathogenesis of AAD, and inhibitors of various types of programmed cell death represent a promising therapeutic strategy. This review discusses the different types of programmed cell death pathways and their features, induction, contributions to AAD development, and therapeutic potential. We also highlight the clinical significance of programmed cell death for further studies.

The aorta is highly heterogeneous, containing many different types of cells that perform sophisticated functions to maintain aortic homeostasis. Recently, single-cell RNA sequencing studies have provided substantial new insight into the heterogeneity of vascular cell types, the comprehensive molecular features of each cell type, and the phenotypic interrelationship between these cell populations. This new information has significantly improved our understanding of aortic biology and aneurysms at the molecular and cellular level. Here, we summarize these findings, with a focus on what single-cell RNA sequencing analysis has revealed about cellular heterogeneity, cellular transitions, communications among cell populations, and critical transcription factors in the vascular wall. We also review the information learned from single-cell RNA sequencing that has contributed to our understanding of the pathogenesis of vascular disease, such as the identification of cell types in which aneurysm-related genes and genetic variants function. Finally, we discuss the challenges and future directions of single-cell RNA sequencing applications in studies of aortic biology and diseases. Graphic Abstract: A graphic abstract is available for this article.

The molecular and cellular processes leading to aortic aneurysm development in Marfan syndrome (MFS) remain poorly understood. In this study, we examined the changes of aortic cell populations and gene expression in MFS by performing single-cell RNA sequencing (scRNA seq) on ascending aortic aneurysm tissues from patients with MFS (n = 3) and age-matched non-aneurysmal control tissues from cardiac donors and recipients (n = 4). The expression of key molecules was confirmed by immunostaining. We detected diverse populations of smooth muscle cells (SMCs), fibroblasts, and endothelial cells (ECs) in the aortic wall. Aortic tissues from MFS showed alterations of cell populations with increased de-differentiated proliferative SMCs compared to controls. Furthermore, there was a downregulation of MYOCD and MYH11 in SMCs, and an upregulation of COL1A1/2 in fibroblasts in MFS samples compared to controls. We also examined TGF-β signaling, an important pathway in aortic homeostasis. We found that TGFB1 was significantly upregulated in two fibroblast clusters in MFS tissues. However, TGF-β receptor genes (predominantly TGFBR2) and SMAD genes were downregulated in SMCs, fibroblasts, and ECs in MFS, indicating impairment in TGF-β signaling. In conclusion, despite upregulation of TGFB1, the rest of the canonical TGF-β pathway and mature SMCs were consistently downregulated in MFS, indicating a potential compromise of TGF-β signaling and lack of stimulus for SMC differentiation.

OBJECTIVE: Using a mouse model of elastin insufficiency that spontaneously develops neointima in the ascending aorta, we sought to understand the origin and phenotypic heterogeneity of smooth muscle cells (SMCs) contributing to intimal hyperplasia. We were also interested in exploring how vascular cells adapt to the absence of elastin. APPROACH AND RESULTS: We used single-cell sequencing together with lineage-specific cell labeling to identify neointimal cell populations in a non-injury, genetic model of neointimal formation. Inactivating elastin production in vascular SMCs results in rapid intimal hyperplasia around breaks in the ascending aorta’s internal elastic lamina. Using lineage-specific Cre drivers to both lineage mark and inactivate elastin expression in the secondary heart field (SHF) and neural crest aortic SMCs, we found that cells with a SHF lineage are significant contributors to neointima formation. We also identified a small population of SHF-derived SMCs underneath and adjacent to the IEL. Within the neointima of SMC-elastin knockout mice, two unique SMC populations were identified that are transcriptionally different from other SMCs. While these cells had a distinct gene signature, they expressed several genes identified in other studies of neointimal lesions, suggesting that some mechanisms underlying neointima formation in elastin insufficiency are shared with adult vessel injury models. CONCLUSIONS: These results highlight the unique developmental origin and transcriptional signature of cells contributing to neointima in the ascending aorta. Our findings also show that the absence of elastin, or changes in elastic fiber integrity, influences the SMC biological niche in ways that lead to altered cell phenotypes.

Background: Ascending thoracic aortic aneurysm (ATAA) is caused by the progressive weakening and dilatation of the aortic wall and can lead to aortic dissection, rupture, and other life-threatening complications. To improve our understanding of ATAA pathogenesis, we aimed to comprehensively characterize the cellular composition of the ascending aortic wall and to identify molecular alterations in each cell population of human ATAA tissues. Methods: We performed single-cell RNA sequencing analysis of ascending aortic tissues from 11 study participants, including 8 patients with ATAA (4 women and 4 men) and 3 control subjects (2 women and 1 man). Cells extracted from aortic tissue were analyzed and categorized with single-cell RNA sequencing data to perform cluster identification. ATAA-related changes were then examined by comparing the proportions of each cell type and the gene expression profiles between ATAA and control tissues. We also examined which genes may be critical for ATAA by performing the integrative analysis of our single-cell RNA sequencing data with publicly available data from genome-wide association studies. Results: We identified 11 major cell types in human ascending aortic tissue; the high-resolution reclustering of these cells further divided them into 40 subtypes. Multiple subtypes were observed for smooth muscle cells, macrophages, and T lymphocytes, suggesting that these cells have multiple functional populations in the aortic wall. In general, ATAA tissues had fewer nonimmune cells and more immune cells, especially T lymphocytes, than control tissues did. Differential gene expression data suggested the presence of extensive mitochondrial dysfunction in ATAA tissues. In addition, integrative analysis of our single-cell RNA sequencing data with public genome-wide association study data and promoter capture Hi-C data suggested that the erythroblast transformation-specific related gene( ERG ) exerts an important role in maintaining normal aortic wall function. Conclusions: Our study provides a comprehensive evaluation of the cellular composition of the ascending aortic wall and reveals how the gene expression landscape is altered in human ATAA tissue. The information from this study makes important contributions to our understanding of ATAA formation and progression.

Atrial fibrillation is the most frequent arrhythmia in both equine and human athletes. Currently, this condition is diagnosed via electrocardiogram (ECG) monitoring which lacks sensitivity in about half of cases when it presents in paroxysmal form. We investigated whether the arrhythmogenic substrate present between the episodes of paroxysmal atrial fibrillation (PAF) can be detected using restitution analysis of normal sinus-rhythm ECGs. In this work, ECG recordings were obtained during routine clinical work from control and horses with PAF. The extracted QT, TQ, and RR intervals were used for ECG restitution analysis. The restitution data were trained and tested using k-nearest neighbor (k-NN) algorithm with various values of neighbors k to derive a discrimination tool. A combination of QT, RR, and TQ intervals was used to analyze the relationship between these intervals and their effects on PAF. A simple majority vote on individual record (one beat) classifications was used to determine the final classification. The k-NN classifiers using two-interval measures were able to predict the diagnosis of PAF with area under the receiving operating characteristic curve close to 0.8 (RR, TQ with k ≥ 9) and 0.9 (RR, QT with k ≥ 21 or TQ, QT with k ≥ 25). By simultaneously using all three intervals for each beat and a majority vote, mean area under the curves of 0.9 were obtained for all tested k-values (3-41). We concluded that 3D ECG restitution analysis can potentially be used as a metric of an automated method for screening of PAF.

Background: The ascending aorta is a common location for aneurysm and dissection. This aortic region is populated by a mosaic of medial and adventitial cells that are embryonically derived from either the second heart field (SHF) or the cardiac neural crest. SHF-derived cells populate areas that coincide with the spatial specificity of thoracic aortopathies. The purpose of this study was to determine whether and how SHF-derived cells contribute to ascending aortopathies. Methods: Ascending aortic pathologies were examined in patients with sporadic thoracic aortopathies and angiotensin II (AngII)–infused mice. Ascending aortas without overt pathology from AngII-infused mice were subjected to mass spectrometry–assisted proteomics and molecular features of SHF-derived cells were determined by single-cell transcriptomic analyses. Genetic deletion of either Lrp1 (low-density lipoprotein receptor–related protein 1) or Tgfbr2 (transforming growth factor–β receptor type 2) in SHF-derived cells was conducted to examine the effect of SHF-derived cells on vascular integrity. Results: Pathologies in human ascending aortic aneurysmal tissues were predominant in outer medial layers and adventitia. This gradient was mimicked in mouse aortas after AngII infusion that was coincident with the distribution of SHF-derived cells. Proteomics indicated that brief AngII infusion before overt pathology occurred evoked downregulation of smooth muscle cell proteins and differential expression of extracellular matrix proteins, including several LRP1 ligands. LRP1 deletion in SHF-derived cells augmented AngII-induced ascending aortic aneurysm and rupture. Single-cell transcriptomic analysis revealed that brief AngII infusion decreased Lrp1 and Tgfbr2 mRNA abundance in SHF-derived cells and induced a unique fibroblast population with low abundance of Tgfbr2 mRNA. SHF-specific Tgfbr2 deletion led to embryonic lethality at E12.5 with dilatation of the outflow tract and retroperitoneal hemorrhage. Integration of proteomic and single-cell transcriptomics results identified PAI1 (plasminogen activator inhibitor 1) as the most increased protein in SHF-derived smooth muscle cells and fibroblasts during AngII infusion. Immunostaining revealed a transmural gradient of PAI1 in both ascending aortas of AngII-infused mice and human ascending aneurysmal aortas that mimicked the gradient of medial and adventitial pathologies. Conclusions: SHF-derived cells exert a critical role in maintaining vascular integrity through LRP1 and transforming growth factor–β signaling associated with increases of aortic PAI1.

Background The process of aortic injury, repair, and remodeling during aortic aneurysm and dissection is poorly understood. We examined the activation of bone marrow (BM)-derived and resident aortic cells in response to aortic injury in a mouse model of sporadic aortic aneurysm and dissection. Materials and methods Wild-type C57BL/6 mice were transplanted with green fluorescent protein (GFP)+ BM cells. For 4 wk, these mice were either unchallenged with chow diet and saline infusion or challenged with high-fat diet and angiotensin II infusion. We then examined the aortic recruitment of GFP+ BM-derived cells, growth factor production, and the differentiation potential of GFP+ BM-derived and GFP− resident aortic cells. Results Aortic challenge induced recruitment of GFP+ BM cells and activation of GFP− resident aortic cells, both of which produced growth factors. Although BM cells and resident aortic cells equally contributed to the fibroblast populations, we did not detect the differentiation of BM cells into smooth muscle cells. Interestingly, aortic macrophages were both of BM-derived (45%) and of non−BM-derived (55%) origin. We also observed a significant increase in stem cell antigen-1 (Sca-1)+ stem/progenitor cells and neural/glial antigen 2 (NG2+) cells in the aortic wall of challenged mice. Although some of the Sca-1+ cells and NG2+ cells were BM derived, most of these cells were resident aortic cells. Sca-1+ cells produced growth factors and differentiated into fibroblasts and NG2+ cells. Conclusions BM-derived and resident aortic cells are activated in response to aortic injury and contribute to aortic inflammation, repair, and remodeling by producing growth factors and differentiating into fibroblasts and inflammatory cells.

Succinylation is a post-translational modification of protein lysine residues with succinyl groups derived from succinyl CoA. Succinylation is considered a significant post-translational modification with the potential to impact protein function which is highly conserved across numerous species. The role of succinylation in the heart, especially in heart failure and myofibril mechanics, remains largely unexplored. Mechanical parameters were measured in myofibrils isolated from failing hearts of ischemic cardiomyopathy patients and non-failing donor controls. We employed mass spectrometry to quantify differential protein expression in myofibrils from failing ischemic cardiomyopathy hearts compared to non-failing hearts. In addition, we combined peptide enrichment by immunoprecipitation with liquid chromatography tandem mass spectrometry to quantitatively analyze succinylated lysine residues in these myofibrils. Several key parameters of sarcomeric mechanical interactions were altered in myofibrils isolated from failing ischemic cardiomyopathy hearts, including lower resting tension and a faster rate of activation. Of the 100 differentially expressed proteins, 46 showed increased expression in ischemic heart failure, while 54 demonstrated decreased expression in ischemic heart failure. Our quantitative succinylome analysis identified a total of 572 unique succinylated lysine sites located on 181 proteins, with 307 significantly changed succinylation events. We found that 297 succinyl-Lys demonstrated decreased succinylation on 104 proteins, while 10 residues demonstrated increased succinylation on 4 proteins. Investigating succinyl CoA generation, enzyme activity assays demonstrated that α-ketoglutarate dehydrogenase and succinate dehydrogenase activities were significantly decreased in ischemic heart failure. An activity assay for succinyl CoA synthetase demonstrated a significant increase in ischemic heart failure. Taken together, our findings support the hypothesis that succinyl CoA production is decreased and succinyl CoA turnover is increased in ischemic heart failure, potentially resulting in an overall decrease in the mitochondrial succinyl CoA pool, which may contribute to decreased myofibril protein succinylation in heart failure.

It is unclear whether intraoperative arterial hypotension is associated with postoperative delirium. We hypothesized that intraoperative hypotension within a range frequently observed in clinical practice is associated with increased odds of delirium after surgery.Adult noncardiac surgical patients undergoing general anesthesia at 2 academic medical centers between 2005 and 2017 were included in this retrospective cohort study. The primary exposure was intraoperative hypotension, defined as the cumulative duration of an intraoperative mean arterial pressure (MAP)55 mm Hg, categorized into and short (15 minutes; median [interquartile range {IQR}], 2 [1-4] minutes) and prolonged (≥15 minutes; median [IQR], 21 [17-31] minutes) durations of intraoperative hypotension. The primary outcome was a new diagnosis of delirium within 30 days after surgery. In secondary analyses, we assessed the association between a MAP decrease of30% from baseline and postoperative delirium. Multivariable logistic regression adjusted for patient- and procedure-related factors, including demographics, comorbidities, and markers of procedural severity, was used.Among 316,717 included surgical patients, 2183 (0.7%) were diagnosed with delirium within 30 days after surgery; 41.7% and 2.6% of patients had a MAP55 mm Hg for a short and a prolonged duration, respectively. A MAP55 mm Hg was associated with postoperative delirium compared to no hypotension (short duration of MAP55 mm Hg: adjusted odds ratio [ORadj], 1.22; 95% confidence interval [CI], 1.11-1.33; P.001 and prolonged duration of MAP55 mm Hg: ORadj, 1.57; 95% CI, 1.27-1.94; P.001). Compared to a short duration of a MAP55 mm Hg, a prolonged duration of a MAP55 mm Hg was associated with greater odds of postoperative delirium (ORadj, 1.29; 95% CI, 1.05-1.58; P = .016). The association between intraoperative hypotension and postoperative delirium was duration-dependent (ORadj for every 10 cumulative minutes of MAP55 mm Hg: 1.06; 95% CI, 1.02-1.09; P =.001) and magnified in patients who underwent surgeries of longer duration (P for interaction = .046; MAP55 mm Hg versus no MAP55 mm Hg in patients undergoing surgery of3 hours: ORadj, 1.40; 95% CI, 1.23-1.61; P.001). A MAP decrease of30% from baseline was not associated with postoperative delirium compared to no hypotension, also when additionally adjusted for the cumulative duration of a MAP55 mm Hg (short duration of MAP decrease30%: ORadj, 1.13; 95% CI, 0.91-1.40; P = .262 and prolonged duration of MAP decrease30%: ORadj, 1.19; 95% CI, 0.95-1.49; P = .141).In patients undergoing noncardiac surgery, a MAP55 mm Hg was associated with a duration-dependent increase in odds of postoperative delirium. This association was magnified in patients who underwent surgery of long duration.

Intraoperative cerebral blood flow is mainly determined by cerebral perfusion pressure and cerebral autoregulation of vasomotor tone. About 1% of patients undergoing noncardiac surgery develop ischemic stroke. We hypothesized that intraoperative hypotension within a range frequently observed in clinical practice is associated with an increased risk of perioperative ischemic stroke within 7 days after surgery.Adult noncardiac surgical patients undergoing general anesthesia at Beth Israel Deaconess Medical Center and Massachusetts General Hospital between 2005 and 2017 were included in this retrospective cohort study. The primary exposure was intraoperative hypotension, defined as a decrease in mean arterial pressure (MAP) below 55 mm Hg, categorized into no intraoperative hypotension, short (15 minutes, median [interquartile range {IQR}], 2 minutes [1-5 minutes]) and prolonged (≥15 minutes, median [IQR], 21 minutes [17-31 minutes]) durations. The primary outcome was a new diagnosis of early perioperative ischemic stroke within 7 days after surgery. In secondary analyses, we assessed the effect of a MAP decrease by30% from baseline on perioperative stroke. Analyses were adjusted for the preoperative STRoke After Surgery (STRAS) prediction score, work relative value units, and duration of surgery.Among 358,391 included patients, a total of 1553 (0.4%) experienced an early perioperative ischemic stroke. About 42% and 3% of patients had a MAP of below 55 mm Hg for a short and a prolonged duration, and 49% and 29% had a MAP decrease by30% from baseline for a short and a prolonged duration, respectively. In an adjusted analysis, neither a MAP55 mm Hg (short duration: adjusted odds ratio [ORadj], 0.95; 95% confidence interval [CI], 0.85-1.07; P = .417 and prolonged duration: ORadj, 1.18; 95% CI, 0.91-1.55; P = .220) nor a MAP decrease30% (short duration: ORadj, 0.97; 95% CI, 0.67-1.42; P = .883 and prolonged duration: ORadj, 1.30; 95% CI, 0.89-1.90; P = .176) was associated with early perioperative stroke. A high a priori stroke risk quantified based on preoperatively available risk factors (STRAS prediction score) was associated with longer intraoperative hypotension (adjusted incidence rate ratio, 1.04; 95% CI, 1.04-1.05; P.001 per 5 points of the STRAS prediction score).This study found no evidence to conclude that intraoperative hypotension within the range studied was associated with early perioperative stroke within 7 days after surgery. These findings emphasize the importance of perioperative cerebral blood flow autoregulation to prevent ischemic stroke.

The clinical impact of rare loss-of-function variants has yet to be determined for most genes. Integration of DNA sequencing data with electronic health records (EHRs) could enhance our understanding of the contribution of rare genetic variation to human disease1. By leveraging 10,900 whole-exome sequences linked to EHR data in the Penn Medicine Biobank, we addressed the association of the cumulative effects of rare predicted loss-of-function variants for each individual gene on human disease on an exome-wide scale, as assessed using a set of diverse EHR phenotypes. After discovering 97 genes with exome-by-phenome-wide significant phenotype associations (P

Atrial fibrillation is the most frequent arrhythmia in both equine and human athletes. Currently, this condition is diagnosed via electrocardiogram (ECG) monitoring which lacks sensitivity in about half of cases when it presents in paroxysmal form. We investigated whether the arrhythmogenic substrate present between the episodes of paroxysmal atrial fibrillation (PAF) can be detected using restitution analysis of normal sinus-rhythm ECGs. In this work, ECG recordings were obtained during routine clinical work from control and horses with PAF. The extracted QT, TQ, and RR intervals were used for ECG restitution analysis. The restitution data were trained and tested using k-nearest neighbor (k-NN) algorithm with various values of neighbors k to derive a discrimination tool. A combination of QT, RR, and TQ intervals was used to analyze the relationship between these intervals and their effects on PAF. A simple majority vote on individual record (one beat) classifications was used to determine the final classification. The k-NN classifiers using two-interval measures were able to predict the diagnosis of PAF with area under the receiving operating characteristic curve close to 0.8 (RR, TQ with k ≥ 9) and 0.9 (RR, QT with k ≥ 21 or TQ, QT with k ≥ 25). By simultaneously using all three intervals for each beat and a majority vote, mean area under the curves of 0.9 were obtained for all tested k-values (3–41). We concluded that 3D ECG restitution analysis can potentially be used as a metric of an automated method for screening of PAF.

Background Cancer is the second leading cause of death globally, and researchers seek to identify modifiable risk factors Over the past several decades, there has been ongoing debate whether opioids are associated with cancer development, metastasis, or recurrence. Basic science, clinical, and observational studies have produced conflicting results. The authors examined the association between prescription opioids and incident cancers using the Surveillance, Epidemiology, and End Results (SEER)-Medicare database. A complex relation was observed between prescription opioids and incident cancer, and cancer site may be an important determinant. Methods By using linked SEER cancer registry and Medicare claims from 2008 through 2013, a case-control study was conducted examining the relation between cancer onset and prior opioid exposure. Logistic regression was used to account for differences between cases and controls for 10 cancer sites. Results Of the population studied (n = 348,319), 34% were prescribed opioids, 79.5% were white, 36.9% were dually eligible (for both Medicare and Medicaid), 13% lived in a rural area, 52.7% had ≥1 comorbidity, and 16% had a smoking-related diagnosis. Patients exposed to opioids had a lower odds ratio (OR) associated with breast cancer (adjusted OR, 0.96; 95% CI, 0.92-0.99) and colon cancer (adjusted OR, 0.90; 95% CI, 0.86-0.93) compared with controls. Higher ORs for kidney cancer, leukemia, liver cancer, lung cancer, and lymphoma, ranging from lung cancer (OR, 1.04; 95% CI, 1.01-1.07) to liver cancer (OR, 1.19; 95% CI, 1.08-1.31), were present in the exposed population. Conclusions The current results suggest that an association exists between prescription opioids and incident cancer and that cancer site may play an important role. These findings can direct future research on specific patient populations that may benefit or be harmed by prescription opioid exposure.

Background Aortic aneurysms and dissections are highly lethal diseases for which an effective treatment strategy is critically needed to prevent disease progression. The nucleotide‐binding oligomerization domain–like receptor pyrin domain containing 3 (NLRP3)–caspase‐1 inflammasome cascade was recently shown to play an important role in aortic destruction and disease development. In this study, we tested the effects of MCC950, a potent, selective NLRP3 inhibitor, on preventing aortic destruction and aortic aneurysm and dissection formation. Methods and Results In a model of sporadic aortic aneurysm and dissection induced by challenging wild‐type mice with a high‐fat, high‐cholesterol diet and angiotensin II infusion, MCC950 treatment significantly inhibited challenge‐induced aortic dilatation, dissection, and rupture in different thoracic and abdominal aortic segments in both male and female mice. Aortic disease reduction by MCC950 was associated with the prevention of NLRP3–caspase‐1 upregulation, smooth muscle cell contractile protein degradation, aortic cell death, and extracellular matrix destruction. Further investigation revealed that preventing matrix metallopeptidase 9 (MMP‐9) expression and activation in macrophages is an important mechanism underlying MCC950's protective effect. We found that caspase‐1 directly activated MMP‐9 by cleaving its N‐terminal inhibitory domain. Moreover, the genetic knockdown of Nlrp3 or Casp‐1 in mice or treatment of mice with MCC950 diminished the challenge‐induced N‐terminal cleavage of MMP‐9, MMP‐9 activation, and aortic destruction. Conclusions Our findings suggest that the NLRP3–caspase‐1 inflammasome directly activates MMP‐9. Targeting the inflammasome with MCC950 is a promising approach for preventing aortic destruction and aortic aneurysm and dissection development.

The incidence of cardiovascular disease (CVD) is higher in cancer survivors than in the general population. Several cancer treatments are recognized as risk factors for CVD, but specific therapies are unavailable. Many cancer treatments activate shared signaling events, which reprogram myeloid cells (MCs) towards persistent senescence-associated secretory phenotype (SASP) and consequently CVD, but the exact mechanisms remain unclear. This study aimed to provide mechanistic insights and potential treatments by investigating how chemo-radiation can induce persistent SASP. We generated ERK5 S496A knock-in mice and determined SASP in myeloid cells (MCs) by evaluating their efferocytotic ability, antioxidation-related molecule expression, telomere length, and inflammatory gene expression. Candidate SASP inducers were identified by high-throughput screening, using the ERK5 transcriptional activity reporter cell system. Various chemotherapy agents and ionizing radiation (IR) up-regulated p90RSK-mediated ERK5 S496 phosphorylation. Doxorubicin and IR caused metabolic changes with nicotinamide adenine dinucleotide depletion and ensuing mitochondrial stunning (reversible mitochondria dysfunction without showing any cell death under ATP depletion) via p90RSK-ERK5 modulation and poly (ADP-ribose) polymerase (PARP) activation, which formed a nucleus-mitochondria positive feedback loop. This feedback loop reprogramed MCs to induce a sustained SASP state, and ultimately primed MCs to be more sensitive to reactive oxygen species. This priming was also detected in circulating monocytes from cancer patients after IR. When PARP activity was transiently inhibited at the time of IR, mitochondrial stunning, priming, macrophage infiltration, and coronary atherosclerosis were all eradicated. The p90RSK-ERK5 module plays a crucial role in SASP-mediated mitochondrial stunning via regulating PARP activation. Our data show for the first time that the nucleus-mitochondria positive feedback loop formed by p90RSK-ERK5 S496 phosphorylation-mediated PARP activation plays a crucial role of persistent SASP state, and also provide preclinical evidence supporting that transient inhibition of PARP activation only at the time of radiation therapy can prevent future CVD in cancer survivors., Graphical abstract Image 1, Highlights • High-throughput screening detects chemo-radiation as p90RSK-ERK5 modulator, which induces senescence-associated secretory phenotype (SASP). • Chemo-radiation instigates mitochondrial (mt) stunning (reversible mt dysfunction without showing any cell death under ATP depletion). • Mt stunning is provoked by p90RSK-ERK5 modulation and PARP activation, which forms a nucleus-mitochondria positive feedback loop. • This feedback loop reprogramed myeloid cells (MCs) to induce a sustained SASP state, and ultimately prime MCs to be more sensitive to reactive oxygen species. • When PARP activity is transiently inhibited at the time of IR, mitochondrial stunning, priming, macrophage infiltration, and coronary atherosclerosis are all eradicated.

Impaired angiogenesis and wound healing carry significant morbidity and mortality in diabetic patients. Metabolic stress from hyperglycemia and elevated free fatty acids have been shown to inhibit endothelial angiogenesis. However, the underlying mechanisms remain poorly understood. In this study, we show that dysregulation of the Hippo–Yes-associated protein (YAP) pathway, an important signaling mechanism in regulating tissue repair and regeneration, underlies palmitic acid (PA)-induced inhibition of endothelial angiogenesis. PA inhibited endothelial cell proliferation, migration, and tube formation, which were associated with increased expression of mammalian Ste20-like kinases 1 (MST1), YAP phosphorylation/inactivation, and nuclear exclusion. Overexpression of YAP or knockdown of MST1 prevented PA-induced inhibition of angiogenesis. When searching upstream signaling mechanisms, we found that PA dysregulated the Hippo–YAP pathway by inducing mitochondrial damage. PA treatment induced mitochondrial DNA (mtDNA) release to cytosol, and activated cytosolic DNA sensor cGAS–STING–IRF3 signaling. Activated IRF3 bound to the MST1 gene promoter and induced MST1 expression, leading to MST1 up-regulation, YAP inactivation, and angiogenesis inhibition. Thus, mitochondrial damage and cytosolic DNA sensor cGAS–STING–IRF3 signaling are critically involved in PA-induced Hippo–YAP dysregulation and angiogenesis suppression. This mechanism may have implication in impairment of angiogenesis and wound healing in diabetes.

Aortic structure and function are controlled by the coordinated actions of different aortic cells and the extracellular matrix. Several pathways have been identified that control the aortic wall in a cell-type–specific manner and play diverse roles in various phases of aortic injury, repair, and remodeling. This complexity of signaling in the aortic wall poses challenges to the development of therapeutic strategies for treating aortic aneurysms and dissections. Here, in part II of this Recent Highlights series on aortic aneurysms and dissections, we will summarize recent studies published in Arteriosclerosis, Thrombosis, and Vascular Biology that have contributed to our knowledge of the signaling pathway–related mechanisms of aortic aneurysms and dissections.

The aortic wall is composed of highly dynamic cell populations and extracellular matrix. In response to changes in the biomechanical environment, aortic cells and extracellular matrix modulate their structure and functions to increase aortic wall strength and meet the hemodynamic demand. Compromise in the structural and functional integrity of aortic components leads to aortic degeneration, biomechanical failure, and the development of aortic aneurysms and dissections (AAD). A better understanding of the molecular pathogenesis of AAD will facilitate the development of effective medications to treat these conditions. Here, we summarize recent findings on AAD published in ATVB . In this issue, we focus on the dynamics of aortic cells and extracellular matrix in AAD; in the next issue, we will focus on the role of signaling pathways in AAD.

The mechanisms underlying pathophysiological regulation of tissue macrophage (Mφ) subsets remain poorly understood. From the expression of 207 Mφ genes comprising 31 markers for 10 subsets, 45 transcription factors (TFs), 56 immunometabolism enzymes, 23 trained immunity (innate immune memory) enzymes, and 52 other genes in microarray data, we made the following findings. (1) When 34 inflammation diseases and tumor types were grouped into eight categories, there was differential expression of the 31 Mφ markers and 45 Mφ TFs, highlighted by 12 shared and 20 group-specific disease pathways. (2) Mφ in lung, liver, spleen, and intestine (LLSI-Mφ) express higher M1 Mφ markers than lean adipose tissue Mφ (ATMφ) physiologically. (3) Pro-adipogenic TFs C/EBPα and PPARγ and proinflammatory adipokine leptin upregulate the expression of M1 Mφ markers. (4) Among 10 immune checkpoint receptors (ICRs), LLSI-Mφ and bone marrow (BM) Mφ express higher levels of CD274 (PDL-1) than ATMφ, presumably to counteract the M1 dominant status via its reverse signaling behavior. (5) Among 24 intercellular communication exosome mediators, LLSI- and BM- Mφ prefer to use RAB27A and STX3 than RAB31 and YKT6, suggesting new inflammatory exosome mediators for propagating inflammation. (6) Mφ in peritoneal tissue and LLSI-Mφ upregulate higher levels of immunometabolism enzymes than does ATMφ. (7) Mφ from peritoneum and LLSI-Mφ upregulate more trained immunity enzyme genes than does ATMφ. Our results suggest that multiple new mechanisms including the cell surface, intracellular immunometabolism, trained immunity, and TFs may be responsible for disease group-specific and shared pathways. Our findings have provided novel insights on the pathophysiological regulation of tissue Mφ, the disease group-specific and shared pathways of Mφ, and novel therapeutic targets for cancers and inflammations.

Background Thoracic aortic aneurysm ( TAA ) and dissection ( TAD ) are characterized by progressive disorganization of the aortic wall matrix, including elastin, a highly immunogenic molecule. Whether acquired autoimmune responses can be detected in TAA / TAD patients who are smokers is unknown. The objectives of this study were to determine whether TAA / TAD smokers have increased T‐cell responses to human elastin fragments, and to determine whether autoimmune responses in TAA / TAD smokers are dependent on chronic obstructive pulmonary disease. Methods and Results In a cross‐sectional study (N=86), we examined peripheral blood CD 4 + T cell responses to elastin fragments in never‐, former‐, or current‐smokers with or without TAA / TAD . CD 4 + T cells were co‐cultured with irradiated autologous peripheral blood CD 1a + / CD 14 + antigen presenting cells pulsed with or without elastin fragments to measure cytokine production. Baseline plasma concentration of anti‐elastin antibodies and elastin‐degrading enzymes (eg, matrix metalloproteinase‐9, and ‐12, and neutrophil elastase) were measured in the same cohort. elastin fragment‐specific CD 4 + T cell expression of interferon‐γ, and anti‐elastin antibodies were dependent on history of smoking in TAA / TAD patients but were independent of chronic obstructive pulmonary disease. Matrix metalloproteinase‐9, and ‐12, and neutrophil elastase plasma concentrations were also significantly elevated in ever‐smokers with TAA / TAD . Conclusions Cigarette smoke is associated with loss of self‐tolerance and induction of elastin‐specific autoreactive T‐ and B‐cell responses in patients with TAA / TAD . Development of peripheral blood biomarkers to track immunity to self‐antigens could be used to identify and potentially prognosticate susceptibility to TAA / TAD in smokers.

SUMMARY Circadian clocks orchestrate daily rhythms in organismal physiology and behavior to promote optimal performance and fitness. In Drosophila, key pacemaker proteins PERIOD (PER) and TIMELESS (TIM) are progressively phosphorylated to perform phase-specific functions. Whereas PER phosphorylation has been extensively studied, systematic analysis of site-specific TIM phosphorylation is lacking. Here, we identified phosphorylation sites of PER-bound TIM by mass spectrometry, given the importance of TIM as a modulator of PER function in the pacemaker. Among the 12 TIM phosphorylation sites we identified, at least two of them are critical for circadian timekeeping as mutants expressing non-phosphorylatable mutations exhibit altered behavioral rhythms. In particular, we observed that CK2-dependent phosphorylation of TIM(S1404) promotes nuclear accumulation of PER-TIM heterodimers by inhibiting the interaction of TIM and nuclear export component, Exportin 1 (XPO1). We propose that proper level of nuclear PER-TIM accumulation is necessary to facilitate kinase recruitment for the regulation of daily phosphorylation rhythm and phase-specific transcriptional activity of CLOCK (CLK). Our results highlight the contribution of phosphorylation-dependent nuclear export of PER-TIM heterodimers to the maintenance of circadian periodicity and identify a new mechanism by which the negative elements of the circadian clock (PER-TIM) regulate the positive elements (CLK-CYC). Finally, because the molecular phenotype of tim(S1404A) non-phosphorylatable mutant exhibits remarkable similarity to that of a mutation in human timeless that underlies familial advanced sleep phase syndrome (FASPS), our results revealed an unexpected parallel between the functions of Drosophila and human TIM and may provide new insights into the molecular mechanisms underlying human FASPS., Graphical Abstract, In Brief Organisms in all domains of life exhibit circadian rhythms. Cai et al. reveal that phosphorylation of TIMELESS modulates kinase accessibility to CLOCK in the nucleus. This mechanism is important in controlling daily phosphorylation rhythm of CLOCK, which is critical for its function as a key regulator of circadian rhythms.

Background The proliferation of pulmonary arterial smooth muscle cells (PASMCs) and subsequent pulmonary vascular remodeling leads to pulmonary arterial hypertension (PAH). Understanding the underlying mechanisms and identifying molecules that can suppress PASMCs proliferation is critical for developing effective pharmacological treatment. We previously showed that plasminogen activator inhibitor-2 (PAI-2) inhibited human PASMC (hPASMCs) proliferation in vitro. However, its inhibitory effect on PAH remains to be determined, and the mechanism remains to be illustrated. Methods We compared serum PAI-2 levels between PAH patients and healthy controls, and examined the correlation between PAI-2 level and disease severity. In monocrotaline-induced PAH rats, we examined the effects of exogenous PAI-2 administration on pulmonary vascular remodeling and PAH development. The effect of PAI-2 and potential mechanisms was further examined in cultured hPASMCs. Results The serum PAI-2 was decreased in PAH patients compared with controls. PAI-2 level was negatively correlated with mean pulmonary arterial pressure and estimated systolic pulmonary arterial pressure in ultrasonic cardiogram, while positively correlated with 6-min walking distance. In rats, administration of exogenous PAI-2 significantly reversed monocrotaline-induced PAH, as indicated by the decrease in right ventricle systolic pressure, right ventricular hypertrophy index and percent media thickness of pulmonary arterioles. Further mechanistic investigation in hPASMCs showed that PAI-2 inhibited cell proliferation by preventing the activation of PI3K/Akt and ERK pathways. Conclusion PAI-2 is downregulated in PAH patients. PAI-2 attenuates PAH development by suppressing hPASMCs proliferation via the inhibition of PI3K/Akt and ERK pathways. PAI-2 may serve as a potential biomarker and therapeutic target for PAH.

Temporal resolution of cellular features associated with a severe COVID-19 disease trajectory is required for understanding skewed immune responses and finding outcome predictors. Here, we performed a longitudinal multi-omics study using a two-centre cohort of 14 patients. We analysed the bulk transcriptome, bulk DNA methylome, and single-cell transcriptome (>358,000 cells, including BCR profiles) of peripheral blood samples harvested from up to 5 time points. Validation was performed in two independent cohorts of COVID-19 patients. Severe COVID-19 was characterized by an increase of proliferating, metabolically hyperactive plasmablasts. Coinciding with critical illness, we also identified an expansion of IFN-activated circulating megakaryocytes and increased erythropoiesis with features of hypoxic signalling. Megakaryocyte- and erythroid cell-derived co-expression modules were predictive of fatal disease outcome. The study demonstrates broad cellular effects of SARS-CoV-2 infection beyond classical immune cells and may serve as an entry point to develop biomarkers and targeted treatments of patients with COVID-19., Graphical Abstract, Highlights • SARS-CoV2 infection elicits dynamic changes of circulating cells in the blood • Severe COVID-19 is characterized by increased metabolically active plasmablasts • Elevation of IFN-activated megakaryocytes and erythroid cells in severe COVID-19 • Cell-type specific expression signatures are associated with a fatal COVID-19 outcome, Bernardes et al. explore COVID-19 disease trajectories by performing longitudinal multi-omics analyses in peripheral blood samples from hospitalized patients. The analyses identify increased numbers of plasmablasts, interferon-activated megakaryocytes and erythroid cells as hallmarks of severe disease, and define molecular signatures linked to a fatal COVID-19 disease outcome.

Supplemental Digital Content is available in the text., Objectives: Managing hemoptysis in chronic thromboembolic pulmonary hypertension can be challenging due to the difficulties in maintaining coagulation homeostasis in affected patients. In this study, we evaluated the efficacy and safety of bronchial artery embolization in treating hemoptysis in chronic thromboembolic pulmonary hypertension patients. Design: Pilot, prospective cohort study. Setting: A large respiratory medical institute. Patients: From January 1, 2012, to December 31, 2017, hospitalized chronic thromboembolic pulmonary hypertension patients were eligible for inclusion. Patients with pulmonary hypertension caused by other conditions, or who failed to participate in the follow-up were excluded. Interventions: Hemoptysis in chronic thromboembolic pulmonary hypertension patients was treated with or without bronchial artery embolization based on whether the bleeding could be stopped with medication alone and patient willingness for bronchial artery embolization treatment. Measurements and Main Results: A total of 328 patients diagnosed with chronic thromboembolic pulmonary hypertension were consecutively collected, 317 patients were completed the follow-up. There were 15 chronic thromboembolic pulmonary hypertension patients with hemoptysis in total, and the occurrence rate of hemoptysis in chronic thromboembolic pulmonary hypertension patients was 4.7%. Among the hemoptysis chronic thromboembolic pulmonary hypertension patients, 10 (67%) underwent bronchial artery embolization, and five (33%) were treated with medication only. The median follow-up period for hemoptysis patients was 7.6 months. In patients underwent bronchial artery embolization treatment, oxygenation index and right heart function showed no significant difference between pre bronchial artery embolization and post bronchial artery embolization. Hemoptysis relapse (20% vs 80%; p = 0.025) and hemoptysis-related mortality (0% vs 40%; p = 0.032) were significantly lower, whereas the overall survival (90% vs 40%; p = 0.040) was higher in patients treated with bronchial artery embolization than in patients treated without bronchial artery embolization. Conclusions: Bronchial artery embolization procedure demonstrated effectiveness and safety to treat hemoptysis in chronic thromboembolic pulmonary hypertension patients at our center, but further controlled studies are needed before it can be considered as an effective therapy for these patients.

Background: Atrial fibrillation (AF) is frequently associated with enhanced inflammatory response. The NLRP3 (NACHT, LRR, and PYD domain containing protein 3) inflammasome mediates caspase-1 activation and interleukin-1β release in immune cells but is not known to play a role in cardiomyocytes (CMs). Here, we assessed the role of CM NLRP3 inflammasome in AF. Methods: NLRP3 inflammasome activation was assessed by immunoblot in atrial whole-tissue lysates and CMs from patients with paroxysmal AF or long-standing persistent (chronic) AF. To determine whether CM-specific activation of NLPR3 is sufficient to promote AF, a CM-specific knockin mouse model expressing constitutively active NLRP3 (CM-KI) was established. In vivo electrophysiology was used to assess atrial arrhythmia vulnerability. To evaluate the mechanism of AF, electric activation pattern, Ca 2+ spark frequency, atrial effective refractory period, and morphology of atria were evaluated in CM-KI mice and wild-type littermates. Results: NLRP3 inflammasome activity was increased in the atrial CMs of patients with paroxysmal AF and chronic AF. CM-KI mice developed spontaneous premature atrial contractions and inducible AF, which was attenuated by a specific NLRP3 inflammasome inhibitor, MCC950. CM-KI mice exhibited ectopic activity, abnormal sarcoplasmic reticulum Ca 2+ release, atrial effective refractory period shortening, and atrial hypertrophy. Adeno-associated virus subtype-9–mediated CM-specific knockdown of Nlrp3 suppressed AF development in CM-KI mice. Finally, genetic inhibition of Nlrp3 prevented AF development in CREM transgenic mice, a well-characterized mouse model of spontaneous AF. Conclusions: Our study establishes a novel pathophysiological role for CM NLRP3 inflammasome signaling, with a mechanistic link to the pathogenesis of AF, and establishes the inhibition of NLRP3 as a potential novel AF therapy approach.

Venous thromboembolism (VTE) recurrence carries significant mortality and morbidity. Accurate risk assessment and effective treatment for patients with acute pulmonary embolism (PE) is important for VTE recurrence prevention. We examined the association of VTE recurrence with risk stratification and PE treatment. We enrolled 627 patients with a first episode of confirmed PE. Baseline clinical information was collected. PE severity was assessed by the European Society of Cardiology's (ESC) risk stratification, the simplified PE Severity Index (sPESI) and the Qanadli score of clot burden. Patients were followed for 1-5 years. The cumulative recurrent VTE and all-cause death were documented. The association between recurrent VTE and risk factors was analyzed. The cumulative incidences of recurrent VTE were 4.5%, 7.3%, and 13.9% at 1, 2, and 5 years of follow-up, respectively. The VTE recurrence was associated with higher (high- and intermediate-) risk stratification predicted by ESC model (HR 1.838, 95% CI 1.318-2.571, P

The past century witnessed a rapid development of respiratory medicine in China. The major burden of respiratory disease has shifted from infectious diseases to chronic noninfectious diseases. Great achievements have been made in improving the national standard of clinical management of various respiratory diseases and in smoking control. The specialty of respiratory medicine is expanding into pulmonary and critical care medicine. Nevertheless, respiratory diseases remain a major public health problem, with new challenges such as air pollution and nosocomial infections. This review describes the history, accomplishments, new challenges, and opportunities in respiratory medicine in China.

The clinical use of cardiac magnetic resonance (CMR) in Australian heart failure (HF) patients has limited evidence.To examine how CMR, compared with routine echocardiography, affects the diagnosis and management of patients with HF.Single-centre retrospective study of HF patients newly referred to the Advanced Heart Failure and Transplant unit at The Prince Charles Hospital, Brisbane. Between January 2010 and December 2014, all patients clinically referred for both CMR and echocardiography in the workup of HF were analysed. Imaging results, electronic records and medical charts were reviewed for final diagnosis and changes in clinical management.A total of 114 new HF referrals was included. Evaluation of HF of uncertain aetiology (70%) was the most common indication for CMR. In 20% of cases, CMR led to a completely new diagnosis or diagnostic confirmation of suspicions raised by echocardiography. Clinical decision-making was altered in 48%, with the greatest impact on decisions regarding revascularisation. Overall, CMR had a significant impact on 50% of patients. In a multivariable model, the only independent variable significantly associated with clinical impact was the presence/absence of late gadolinium enhancement (P0.001). Importantly, body mass index, echocardiography image quality and the presence of sinus rhythm did not show statistical significance in the multivariate analysis.CMR makes a substantial contribution to both the diagnosis and management of HF patients over and above standard echocardiography. This study provides evidence of its clinical utility in the HF population in Australia and supports the role of CMR in the routine assessment of this cohort.

Sporadic aortic aneurysm and dissections (AADs) are common vascular diseases that carry a high mortality rate. ADAMTS-4 (a disintegrin-like and metalloproteinase with thrombospondin motifs-4) is a secreted proteinase involved in inflammation and matrix degradation. We previously showed ADAMTS-4 levels were increased in human sporadic descending thoracic AAD (TAAD) samples. Here, we provide evidence that ADAMTS-4 contributes to aortic destruction and sporadic AAD development. In a mouse model of sporadic AAD induced by a high-fat diet and angiotensin II infusion, ADAMTS-4 deficiency (Adamts-4−/−) significantly reduced challenge-induced aortic diameter enlargement, aneurysm formation, dissection and aortic rupture. Aortas in Adamts-4−/− mice showed reduced elastic fibre destruction, versican degradation, macrophage infiltration, and apoptosis. Interestingly, ADAMTS-4 was directly involved in smooth muscle cell (SMC) apoptosis. Under stress, ADAMTS-4 translocated to the nucleus in SMCs, especially in apoptotic SMCs. ADAMTS-4 directly cleaved and degraded poly ADP ribose polymerase-1 (a key molecule in DNA repair and cell survival), leading to SMC apoptosis. Finally, we showed significant ADAMTS-4 expression in aortic tissues from patients with sporadic ascending TAAD, particularly in SMCs. Our findings indicate that ADAMTS-4 induces SMC apoptosis, degrades versican, promotes inflammatory cell infiltration, and thus contributes to sporadic AAD development.

There are no approved drugs for the treatment of heart failure with preserved ejection fraction (HFpEF), which is characterized by left ventricular (LV) diastolic dysfunction. We demonstrate that ITF2357 (givinostat), a clinical-stage inhibitor of histone deacetylase (HDAC) catalytic activity, is efficacious in two distinct murine models of diastolic dysfunction with preserved EF. ITF2357 blocked LV diastolic dysfunction due to hypertension in Dahl salt-sensitive (DSS) rats and suppressed aging-induced diastolic dysfunction in normotensive mice. HDAC inhibitor-mediated efficacy was not due to lowering blood pressure or inhibiting cellular and molecular events commonly associated with diastolic dysfunction, including cardiac fibrosis, cardiac hypertrophy, or changes in cardiac titin and myosin isoform expression. Instead, ex vivo studies revealed impairment of cardiac myofibril relaxation as a previously unrecognized, myocyte-autonomous mechanism for diastolic dysfunction, which can be ameliorated by HDAC inhibition. Translating these findings to humans, cardiac myofibrils from patients with diastolic dysfunction and preserved EF also exhibited compromised relaxation. These data suggest that agents such as HDAC inhibitors, which potentiate cardiac myofibril relaxation, hold promise for the treatment of HFpEF in humans.

Background D-dimer levels are elevated in patients with acute aortic dissection (AAD). Although D-dimer levels have been used to rule out AAD within 24 h of symptom onset, it is unknown whether they may be used reliably after 24 h but within the acute period. Here, we tested the hypothesis that D-dimer levels remain elevated in AAD patients for at least 10 d after dissection onset. Materials and methods D-dimer levels were measured in preoperative heparinized plasma samples from 100 patients with confirmed AAD for up to 10 d after onset of dissection. When possible, serial samples were obtained for ≥2 d. D-dimer levels were measured in fibrinogen equivalent units using a BCS XP automated coagulation analyzer, which is approved for citrated samples. Therefore, we first validated our samples by comparing D-dimer levels in heparinized and citrated plasma samples from 29 individuals, including patients with and without aortic disease and healthy donors. Results The correlation between heparinized and citrated plasma samples was 0.991 ( P ≤ 0.001). At a threshold of 1.6 μg/mL, the overall sensitivity of the D-dimer assay in AAD patients up to 10 d after onset of dissection was 95.3%. Conclusions D-dimer levels remained elevated in AAD patients over a 10-d period after dissection onset and may be helpful in ruling out AAD in patients who seek treatment after the first 24 h but within the acute period. Heparinized plasma samples may be substituted for citrated samples when evaluating D-dimer levels using the BCS XP coagulation analyzer.

Objective: The pathogenesis of non-familial, sporadic ascending aortic aneurysms (SAAA) is poorly understood, and the relationship between ascending aortic atherosclerosis and medial degeneration is unclear. We evaluated the prevalence and severity of aortic atherosclerosis and its association with medial degeneration in SAAA. Methods and results: Atherosclerosis was characterized in ascending aortic tissues collected from 68 SAAA patients (mean age, 62.9 � 12.0 years) and 15 controls (mean age, 56.6 � 11.4 years [P ¼ 0.07]) by using a modified American Heart Association classification system. Upon histologic examination, 97% of SAAA patientsand73%ofcontrolsshowedatheroscleroticchanges.MostSAAAsampleshadintermediate(types2 and 3, 35%) or advanced atherosclerosis (types � 4; 40%), whereas most control samples showed minimal atherosclerosis (none or type 1, 80%; P < 0.001 after adjusting for age). In a separate analysis, we examined the total incidence and grade distribution of medial degenerative changes among SAAA samples according toatherosclerosisgrade.Advancedatherosclerosiswasassociatedwithhighergradesofsmoothmusclecell depletion (P < 0.001), elastic fiber depletion (P ¼ 0.02), elastic fiber fragmentation (P < 0.001), and mucopolysaccharide accumulation (P ¼ 0.04). Aortic diameter was larger in SAAA patients with advanced atherosclerosis than in patients with minimal (P ¼ 0.04) or intermediate atherosclerosis (P ¼ 0.04). Immunostaining showed marked CD3þ T-cell and CD68þ macrophage infiltration, MMP-2 and MMP-9 production, and cryopyrin expression in the medial layer adjacent to atherosclerotic plaque. Conclusions: SAAA tissues exhibited advanced atherosclerosis that was associated with severe medial degeneration and increased aortic diameter. Our findings suggest a role for atherosclerosis in the progression of sporadic ascending aortic aneurysms.

Thoracic aortic dissection (TAD) is a highly lethal vascular disease. In many patients with TAD, the aorta progressively dilates and ultimately ruptures. Dissection formation, progression, and rupture cannot be reliably prevented pharmacologically because the molecular mechanisms of aortic wall degeneration are poorly understood. The key histopathologic feature of TAD is medial degeneration, a process characterized by smooth muscle cell depletion and extracellular matrix degradation. These structural changes have a profound impact on the functional properties of the aortic wall and can result from excessive protease-mediated destruction of the extracellular matrix, altered signaling pathways, and altered gene expression. Review of the literature reveals differences in the processes that lead to ascending versus descending and sporadic versus hereditary TAD. These differences add to the complexity of this disease. Although tremendous progress has been made in diagnosing and treating TAD, a better understanding of the molecular, cellular, and genetic mechanisms that cause this disease is necessary to developing more effective preventative and therapeutic treatment strategies.

Bleeding refers to the most important complication during anticoagulation therapy in patients with pulmonary embolism (PE). However, the incidence and risk factors of bleeding in Chinese population with anticoagulant therapy remains unknown. Although diabetes mellitus (DM) has been demonstrated to increase the risk of PE, little information of its influence on anticoagulation-associated bleeding risk can be available. In our study, 563 acute PE patients, who fulfilled the including criteria were enrolled from a single center and received conventional anticoagulant therapy. And there were 539 patients completed the 3 months following-up. The cumulative incidences of major bleeding (MB) and clinically relevant non-major bleeding (CRNMB) were 3.0% (95% CI 1.01–3.05) and 14.0% (95% CI 1.47–5.21), respectively. Besides, anemia (OR 3.52, 95% CI 1.12–11.41) and recent history of MB (OR 8.14, 95% CI 1.41–31.95) were independently associated with MB. Age >65 year (OR 1.51, 95% CI 1.12–3.11), cancer (OR 2.01, 95% CI 1.12–4.01) and therapeutic range (TTR) during 3 months (OR 0.93, 95% CI 0.91–0.98) were independently associated with CRNMB. Additionally, DM was an independent risk factor for both MB (OR 2.11, 95% CI 1.10–4.12) and CRNMB (OR 2.11, 95% CI 1.10–4.12). Notably, the incidence of MB or CRNMB was significantly higher in DM patients than non-DM patients. At the end of 3-month follow-up, the HbA1C in CRNMB group was 8.3%, yet it was 7.0% in non-CRNMB group among diabetic patients (p = 0.04). In conclusions, the bleeding rates are high in patients with acute PE who receive anticoagulant therapy. In addition to the already known bleeding risk factors, DM can also increase the bleeding risk significantly. Thus, good glycemic control may be essential after prescription of anticoagulant therapy.

Rationale: Aortic aneurysm and dissection (AAD) are major diseases of the adult aorta caused by progressive medial degeneration of the aortic wall. Although the overproduction of destructive factors promotes tissue damage and disease progression, the role of protective pathways is unknown. Objective: In this study, we examined the role of AKT2 in protecting the aorta from developing AAD. Methods and Results: AKT2 and phospho-AKT levels were significantly downregulated in human thoracic AAD tissues, especially within the degenerative medial layer. Akt2- deficient mice showed abnormal elastic fibers and reduced medial thickness in the aortic wall. When challenged with angiotensin II, these mice developed aortic aneurysm, dissection, and rupture with features similar to those in humans, in both thoracic and abdominal segments. Aortas from Akt2 -deficient mice displayed profound tissue destruction, apoptotic cell death, and inflammatory cell infiltration that were not observed in aortas from wild-type mice. In addition, angiotensin II–infused Akt2- deficient mice showed significantly elevated expression of matrix metalloproteinase-9 (MMP-9) and reduced expression of tissue inhibitor of metalloproteinase-1 (TIMP-1). In cultured human aortic vascular smooth muscle cells, AKT2 inhibited the expression of MMP-9 and stimulated the expression of TIMP-1 by preventing the binding of transcription factor forkhead box protein O1 to the MMP-9 and TIMP-1 promoters. Conclusions: Impaired AKT2 signaling may contribute to increased susceptibility to the development of AAD. Our findings provide evidence of a mechanism that underlies the protective effects of AKT2 on the aortic wall and that may serve as a therapeutic target in the prevention of AAD.

Background ADAMTS (a disintegrin and metalloproteinase with thrombospondin motifs) is a recently identified family of extracellular metalloproteinases that has been shown to participate in tissue destruction. We hypothesized that ADAMTS-1 and ADAMTS-4 expression is increased in aortic tissues from patients with thoracic aortic aneurysms and dissections. Methods We examined ADAMTS-1 and ADAMTS-4 expression in human descending thoracic aortic aneurysms (n = 14), chronic descending thoracic aortic dissections (n = 16), and descending thoracic aortas from age-matched control organ donors (n = 12). In these tissues, we also evaluated the degradation of versican, a proteoglycan substrate of ADAMTS-1 and ADAMTS-4. In cultured macrophages, we examined whether ADAMTS-4 functions in macrophage infiltration by using a transwell assay. Results ADAMTS-1 and ADAMTS-4 protein and mRNA expression was significantly higher in thoracic aortic aneurysm and dissection tissues than in control aortic tissues. Double immunofluorescence staining showed the expression of ADAMTS-1 and ADAMTS-4 in smooth muscle cells and macrophages. Consistent with the upregulation of ADAMTS-1 and ADAMTS-4 in thoracic aortic aneurysm and dissection tissues, versican was degraded significantly more in these tissues than in control aortic tissues. In cultured macrophages, transforming growth factor-β increased ADAMTS-4 protein levels and induced macrophage invasion, and the knockdown of ADAMTS-4 reduced cell invasion. Conclusions Increased expression of ADAMTS proteins may promote thoracic aortic aneurysm progression by degrading versican and facilitating macrophage invasion.

AIM Chronic kidney disease (CKD) is increasingly recognized as a predictor of end-stage renal and cardiovascular disease. There is no data on CKD prevalence in numerous minority communities of China such as the Guangxi Jing community. We determined CKD prevalence and related risk factors in Jing adults. METHODS A stratified cluster random sampling method was used in this study comprising 757 Jing adults. Questionnaires, physical examinations and laboratory tests including measurements of urinary albumin and hematuria, were performed. Estimated glomerular filtration rate (eGFR) was calculated using the improved Chinese population MDRD formula. CKD-related risk factors were also examined. RESULTS After standardization for age and gender, the prevalence of albuminuria, haematuria and eGFR < 60 ml/min per 1.73 m2 was 12.5%, 3.8% and 0.4%, respectively Overall CKD prevalence was 15.3%, while the awareness rate was only 11.6%. Females had a significantly higher (p < 0.05) prevalence of albuminuria, hematuria and eGFR < 60 ml/min compared to males. CKD prevalence tended to increase significantly (< 0.05) with increase in age. Using the standardized age and gender ratios, the prevalence of hypertension, diabetes, hyperlipidemia and hyperuricemia was 14.8%, 5.2%, 38% and 16.2%, respectively, with awareness of 41.0%, 41.2%, 6.6% and 0.9%. Prevalence of overweight or obesity status and metabolic syndrome was 12.1% and 3.0%. Females showed a significantly higher prevalence of hyperuricemia and obesity or overweight status. CKD prevalence was also significantly higher in people with risk diseases. Regression analysis showed that age, gender, hypertension, high cholesterol and diabetes were CKD-related risk factors, while culture (higher education level) was a protective factor. CONCLUSION Jing adults showed a high CKD prevalence of 15.3%, with a low awareness rate of 11.6%. Older subjects and females were more susceptible with a high prevalence of hypertension, diabetes, hyperlipidemia, metabolic syndrome etc. being associated closely with CKD.

Objective— Increasing evidence suggests that contractile dysfunction in smooth muscle cells (SMCs) plays a critical role in aortic biomechanical dysfunction and aortic aneurysm and dissection (AAD) development. However, the mechanisms underlying SMC contractile dysfunction in sporadic AAD are poorly understood. In this study, we examined the role of the NLRP3 (nucleotide oligomerization domain–like receptor family, pyrin domain containing 3)–caspase-1 inflammasome, a key inflammatory cascade, in SMC contractile dysfunction in AAD. Approach and Results— We observed significant SMC contractile protein degradation in aortas from patients with sporadic thoracic AAD. The contractile protein degradation was associated with activation of the NLRP3–caspase-1 inflammasome cascade. In SMCs, caspase-1 bound and directly cleaved and degraded contractile proteins, leading to contractile dysfunction. Furthermore, Nlrp3 or caspase-1 deficiency in mice significantly reduced angiotensin II–induced contractile protein degradation, biomechanical dysfunction, and AAD formation in both thoracic and abdominal aortas. Finally, blocking this cascade with the inflammasome inhibitor, glyburide (an antidiabetic medication), reduced angiotensin II–induced AAD formation. Conclusions— Inflammasome-caspase-1–mediated degradation of SMC contractile proteins may contribute to aortic biomechanical dysfunction and AAD development. This cascade may be a therapeutic target in AAD formation. In addition, glyburide may have protective effects against AAD development.

Background The hallmark of thoracic aortic aneurysms and dissections (TAAD) is progressive medial degeneration, which can result from excessive tissue destruction and insufficient repair. Although multipotent stem cells (SCs) are important in tissue repair, their role in TAAD is unknown. We sought to determine whether SCs are more abundant in TAAD tissue than in control tissues, and whether SCs within the diseased aortic wall differentiate into functionally relevant cell types. Methods Using immunohistochemistry, we compared the abundance of STRO-1+ cells, c-kit+ cells, and CD34+ cells in aortic tissue from patients with descending thoracic aortic aneurysms (n = 12), patients with chronic descending thoracic aortic dissections (n = 18), and age-matched organ donors (n = 5). Using double immunofluorescence staining, we evaluated SC differentiation into smooth muscle cells, fibroblasts, and macrophages. Results All three cell types were significantly more abundant in the media and adventitia of TAAD tissues than in control tissues. We identified subsets of STRO-1+ cells, c-kit+ cells, and CD34+ cells that also expressed the smooth muscle cell marker SM22-α or fibroblast-specific protein-1, suggesting SC differentiation into smooth muscle cells or fibroblasts. Other STRO-1+ cells expressed the macrophage marker CD68, suggesting differentiation into inflammatory cells. Conclusions Stem cells are more abundant in TAAD tissue than in normal aortic tissue. Differentiation of SCs into smooth muscle cells, fibroblasts, and inflammatory cells within the diseased aortic wall suggests that SCs might be involved in both reparative and destructive remodeling processes in TAAD. Understanding the regulation of SC-mediated aortic remodeling will be a critical step toward designing strategies to promote aortic repair and prevent adverse remodeling.

Although caffeine consumption is common and generally believed to affect bladder function, little is known about caffeine intake and incident urinary incontinence.We performed a prospective cohort study in 65,176 women 37 to 79 years old without incontinence in the Nurses' Health Study and the Nurses' Health Study II. Incident incontinence was identified from questionnaires during 4 years of followup. Caffeine intake was measured using food frequency questionnaires administered before incontinence development. The multivariate adjusted relative risk of the relation between caffeine intake and incontinence risk as well as attributable risk were calculated.Caffeine was not associated with incontinence monthly or more. However, there was a modest, significantly increased risk of incontinence at least weekly in women with the highest (greater than 450 mg) vs the lowest (less than 150 mg) daily intake (RR 1.19, 95% CI 1.06-1.34) and a significant trend of increasing risk with increasing intake (p for trend = 0.01). This risk appeared focused on incident urgency incontinence (greater than 450 vs less than 150 mg daily, RR 1.34, 95% CI 1.00-1.80, p for trend = 0.05) but not on stress or mixed incontinence (p for trend = 0.75 and 0.19, respectively). The attributable risk of urgency incontinence associated with high caffeine intake was 25%.Findings suggest that high but not lower caffeine intake is associated with a modest increase in the incidence of frequent urgency incontinence. A fourth of the cases with the highest caffeine consumption would be eliminated if high caffeine intake were eliminated. Confirmation of these findings in other studies is needed before recommendations can be made.

Objectives— Although cadmium (Cd) is an important and common environmental pollutant and has been linked to cardiovascular diseases, little is known about its effects in initial stages of atherosclerosis. Methods and Results— In the 195 young healthy women of the Atherosclerosis Risk Factors in Female Youngsters (ARFY) study, cadmium (Cd) level was independently associated with early atherosclerotic vessel wall thickening (intima-media thickness exceeding the 90th percentile of the distribution; multivariable OR 1.6[1.1.–2.3], P =0.016). In line, Cd-fed ApoE knockout mice yielded a significantly increased aortic plaque surface compared to controls (9.5 versus 26.0 mm 2 , P Conclusion— Our research suggests Cd has promoting effects on early human and murine atherosclerosis, which were partly offset by high Zn concentrations.

OBJECTIVE Oxidative stress induced by free fatty acids contributes to the development of cardiovascular diseases in patients with metabolic syndrome. Reducing oxidative stress may attenuate these pathogenic processes. Activation of AMP-activated protein kinase (AMPK) has been reported to reduce intracellular reactive oxygen species (ROS) levels. The thioredoxin (Trx) system is a major antioxidant system. In this study, we investigated the mechanisms involved in the AMPK-mediated regulation of Trx expression and the reduction of intracellular ROS levels. RESEARCH DESIGN AND METHODS We observed that activation of AMPK by 5-aminoimidazole-4-carboxamide ribonucleotide (AICAR) significantly reduced ROS levels induced by palmitic acid in human aortic endothelial cells. Activation of AMPK increased expression of the antioxidant Trx, which mediated the ROS reduction. RT-PCR showed that AMPK regulated Trx at the transcriptional level. RESULTS Forkhead transcription factor 3 (FOXO3) was identified as the target transcription factor involved in the upregulation of Trx expression. FOXO3 bound to the Trx promoter, recruited the histone acetylase p300 to the Trx promoter, and formed a transcription activator complex, which was enhanced by AICAR treatment. AMPK activated FOXO3 by promoting its nuclear translocation. We further showed that AICAR injection increased the expression of Trx and decreased ROS production in the aortic wall of ApoE−/− mice fed a high-fat diet. CONCLUSIONS These results suggest that activation of the AMPK-FOXO3 pathway reduces ROS levels by inducing Trx expression. Thus, the AMPK-FOXO3-Trx axis may be an important defense mechanism against excessive ROS production induced by metabolic stress and could be a therapeutic target in treating cardiovascular diseases in metabolic syndrome.

Thoracic aortic dissection, one of the major diseases affecting the aorta, carries a very high mortality rate. Improving our understanding of the pathobiology of this disease may help us develop medical treatments to prevent dissection and subsequent aneurysm formation and rupture. Dissection is associated with degeneration of the aortic media. Recent studies have shown increased expression and activation of a family of proteolytic enzymes-called matrix metalloproteinases (MMPs)-in dissected aortic tissue, suggesting that MMPs may play a major role in this disease. Inhibition of MMPs may be beneficial in reducing MMP-mediated aortic damage associated with dissection. This article reviews the recent literature and summarizes our current understanding of the role of MMPs in the pathobiology of thoracic aortic dissection. The potential importance of MMP inhibition as a future treatment of aortic dissection is also discussed.