bluuebunny/crossref_metadata_2025_split huggingface dataset:
Presence of adipose tissue in aortic valves from aortic regurgitation patients: pathophysiological role and clinical implications
Authors: Sadaba Cipriain A , Navarro Echeverria A.M , Tiraplegui Garjon C.R , Garcia De La Pena Urtasun A , Arrieta Paniagua V , Matilla Cuenca L , Alvarez Asiain V , Fernandez-Celis A , Gainza Calleja A , Sadaba Sagredo R , Lopez-Andres N 
Published: November 2020

Abstract

Introduction
Adipose tissue is a common constituent of the heart and it is located, without great clinical relevance, frequently in the pericardium. The presence of adipose tissue in the aortic valve is rare, with unknown significance on valve structural properties and function. Aortic regurgitation (AR) is the third most prevalent valve disease, although it is uncommon to find it in isolation. Myxoid degeneration may be the cause or result of AR, although the pathophysiology remains poorly understood.

Purpose
To describe and characterize the presence of adipose tissue in the aortic valves from a cohort of AR patients.

Methods
116 patients undergoing aortic valve replacement due to severe AR were enrolled. We classified them in two groups according to the histological results showing presence or absence of adipose tissue in the aortic valves.
In the valve tissue molecular analysis were performed by RT-PCR, Western Blot and ELISA to analyze markers of adipocytes (leptin, adiponectin, resistin), inflammation (Rantes, interleukin-6, interleukin-1β), extracellular matrix remodeling (metalloproteinases-1, -2 and -9), proteoglycans (aggrecan, hyaluronan, lumican, syndecan-1, decorin) and fibrosis (collagens, fibronectin).

Results
Adipose tissue was found in 63% of the aortic valves analyzed. Baseline characteristics (age, hypertension, dyslipidemia, diabetes, smoking, left ventricular telediastolic diameter, left ventricular systolic function, ascending aorta) were similar in patients presenting valve adipose tissue as compared with patients without valve adipose tissue. Valves containing adipocytes exhibited a higher leptin content (p&lt;0.001), fibronectin (p&lt;0.01), decorin (p&lt;0,0001), hyaluronan (p=0.03), aggrecan (p=0.04) and metalloproteinase 1 (p=0.03). Interestingly, the presence of adipocytes in the valve was positively correlated with valve thickness measured by echocardiogram (Pearson chi2 statistical significance = 26.3345 p&lt;0.001).

Conclusion
To our knowledge, this is the first study that describes the presence of adipose cells in aortic valves from a cohort of AR patients. Aortic valves containing adipocytes were thicker and exhibited significant higher levels of proteoglycans, suggesting that adipocytes could contribute to the myxomatous degeneration process. Our results propose that the valve adipose tissue could play a role in the pathophysiology of AR.

Funding Acknowledgement
Type of funding source: Public hospital(s). Main funding source(s): Gobierno de Navarra
Clec4e signalling influences left-ventricular functional recovery in a murine model of myocardial ischemia-reperfusion injury
Authors: Veltman D , Gillijns H , Caluwe E , Wu M , Vanhaverbeke M , Gsell W , Himmelreich U , Sinnaeve P , Janssens S 
Published: November 2020

Abstract

Introduction
The acute inflammatory response contributes substantially to functional recovery and remodelling of the left ventricle after acute ischemic injury. Previously, we have shown that the C-Type Lectin Receptor CLEC4E plays a role in early leukocyte recruitment during the acute inflammatory response of ischemia-reperfusion injury (I/R). However, the role of CLEC4E signalling in functional recovery of the left ventricle after I/R remains unknown. Therefore, we studied the chronic inflammatory response and left-ventricular remodelling in murine gene deletion model of Clec4e, subjected to I/R.

Methods
In anesthetized C57Bl6/J wild-type (n=14) and Clec4e−/− (n=13) mice, we transiently occluded the left-descending artery for 60 min, followed by 4 weeks reperfusion (I/R). A blood sample was collected at 90 minutes reperfusion to measure high-sensitivity troponin I (TnI) levels, as a surrogate marker of cardiac damage. At 4 weeks, mice underwent MRI (7T) to investigate the effect of Clec4e-gene deletion on LV-remodelling.

Results
Plasma TnI-levels showed no statistical difference between both groups, indicating that the initial insult was comparable. In wild-type mice, plasma TnI-levels negatively correlated with ejection fraction (EF, R2=0.92 p&lt;0.0001) at 4 weeks I/R, while Clec4e−/− mice showed preserved EF, irrespective of 90 minutes TnI-levels. MRI-analysis at 4 weeks after I/R showed significantly smaller end-diastolic and end-systolic volumes in Clec4e−/− mice, together with a trend towards a higher ejection fraction, suggesting better preserved structural and functional LV-remodelling (Fig.1).

Conclusion
The inflammatory leukocyte-associated Clec4e signalling pathway impairs functional recovery of the left ventricle after myocardial I/R injury. Inhibition of the Clec4e receptor may be a promising strategy in the treatment of ischemic injury.
Figure 1

Funding Acknowledgement
Type of funding source: Private grant(s) and/or Sponsorship. Main funding source(s): Scholarship Ir. Jozef en Mevr. Reinhilde De Swerts 2018-2022 by the Royal Academy of Medicine of Belgium
Nur77 deficiency exacerbates cardiac fibrosis after myocardial infarction through promoting endothelial to mesenchymal transition
Authors: Qin Q , Chen J.H , Jia J.B , Qian J.Y , Ge J.B 
Published: November 2020

Abstract

Background
Cardiac fibrosis is a reparative process after myocardial infarction (MI), which leads to cardiac remodeling and finally heart failure. Endothelial-to-mesenchymal transition (EndMT) is induced after MI and contributes to cardiac fibrosis after MI. Orphan nuclear receptor Nur77 is a key regulator of inflammation, angiogenesis, proliferation, and apoptosis in vascular endothelial cells. Here, we investigated the role of orphan nuclear receptor Nur77 in EndMT and cardiac fibrosis after MI.

Methods and results
Cardiac fibrosis was induced through MI by ligation of the left anterior descending coronary artery. Results suggested that Nur77 knockout aggravated cardiac dysfunction and cardiac fibrosis 30 days after MI. Moreover, Nur77 deficency resulted in enhanced EndMT as shown by increased expression of FSP-1, SM22α, Snail and decreased expression of PECAM-1 and eNOS compared with WT mice after MI. Then we found overexpression Nur77 in HCAECs significantly inhibited IL-1β and TGFβ2 induced EndMT, as shown by reduced transition to a fibroblast-like phenotype and preserved angiogenesis potential. Mechanistically, we demonstrated that Nur77 downregulated EndMT through inhibiting NF-κB-dependent pathway

Conclusion
Nur77 plays a role in cardiac fibrosis through inhibition of EndMT, and may be a promising target for therapy of cardiac fibrosis after MI.
Nur77 inhibited EndMT

Funding Acknowledgement
Type of funding source: Public grant(s) – National budget only. Main funding source(s): National Natural Science Foundation of China
Circulating pro fibrotic protein promotes fibrosis in liver
Authors: Hsiao Y , Shimizu I , Yoshida Y , Ikegami R , Hayashi Y , Suda M , Katsuumi G , Wakasugi T , Nakao M , Minamino T 
Published: November 2020

Abstract

Background/Introduction
Non-alcoholic steatohepatitis (NASH), driven by the obesity epidemic, has become the most common form of liver disease. Inflamed visceral adipose tissue secretes pro-inflammatory adipokines that are causal for systemic metabolic disorders. Role of adipokines in NASH, especially those from brown adipose tissues (BATokine) remain unclear.

Purpose
To show the pathogenic role of BATokine in NASH.

Methods
To identify and characterize the pathological roles of pro-fibrotic BATokine, we generated a murine obese NASH model by imposing a high fat diet in C57BL6/NCr mice, and murine systemic or BAT specific knockout (KO) models. We also conducted functional in-vitro studies with differentiated brown adipocytes.

Results
Analyzing two sets of DNA micro array data with bioinformatics, we identified a secreted form pro-fibrotic protein (sPFP) expressed in dysfunctional brown adipose tissues (BAT) in mice. Testing our biobank samples, we found this protein increased in plasma of NASH patients. We generated a murine obese NASH model by imposing a high fat diet in C57BL6/NCr mice for 9–10 months since 4 weeks of age, and found that sPFP is produced predominantly by BAT. In this model, we also found that sPFP increased in plasma. We generated a murine systemic or BAT specific sPFP knockout (KO) models and found that liver fibrosis ameliorated in these models. We also suppressed circulating sPFP with a peptide vaccine targeting this molecule, and found that sPFP vaccination therapy inhibited liver fibrosis. Next, we generated sPFP gain of function (GOF) model by the administration of plasmid encoding sPFP into skeletal muscle. Liver fibrosis augmented in sPFP-GOF model, and these results suggested that sPFP has causal role for the progression of fibrotic response in liver. In vitro studies with differentiated brown adipocytes showed that metabolic stress increased c-Fos in nuclear, and this was causal for an increase in sPFP level.

Conclusions
Our results suggest that one of the BATokines, sPFP, contributes for the progression of fibrotic responses in obese-NASH model. Inhibition of sPFP may become a therapy for NASH or obesity related fibrotic disorders.

Funding Acknowledgement
Type of funding source: None
Smooth muscle cell-specific SOCS3 deficiency promote pericardial fibrosis and diastolic dysfunction in aging mice
Authors: Yanai T , Yasukawa H , Mawatari K , Sasaki T , Takahashi J , Nohara S , Shimozono K , Shibata T , Okabe K , Yamamoto M , Fukumoto Y 
Published: November 2020

Abstract

Background
Suppressor of cytokine signaling-3 (SOCS3) is a cytokine-inducible negative regulator of signal transducer and activator of transcription-3 (STAT3) signaling pathway. We have previously shown that cardiac-specific SOCS3 deficiency spontaneously develop cardiac dysfunction with advanced age. However, the role of SOCS3 in smooth muscle cells in cardiovascular pathophysiology remains elusive. In this study, we determined whether STAT3 and SOCS3 in smooth muscle cells would play a role in cardiovascular pathophysiology.

Methods and results
To target inactivation of the SOCS3 gene to smooth muscle cells, SOCS3-flox mice were bred with transgenic mice expressing Cre recombinase under control of the mouse SM22-α promoter (sm-SOCS3-KO mice). Left ventricular weight to body weight ratio was significantly increased in sm-SOCS3-KO mice compared with wild-type mice at 12 months of age (p&lt;0.05). Echocardiographic analyses of smSOCS3-KO mice showed significantly increased left ventricular diastolic dysfunction compared with wild-type from 12 months of age (p&lt;0.05). Sirius-red staining revealed that thickness of pericardium and cardiac interstitial fibrosis in sm-SOCS3-KO mice were markedly greater compared with wild-type mice at 12 months of age (p&lt;0.05). Western blot analyses showed that phosphorylated STAT3 was significantly increased in sm-SOCS3-KO hearts compared with wild-type mice at 12 months of age (p&lt;0.05), whereas no significant differences were observed at 2 months of age. To investigate the mechanism that gave rise to promoted cardiac fibrosis and diastolic dysfunction during aging in sm-SOCS3-KO, we conducted a real-time PCR array analysis for fibrosis. The expression of pro-fibrotic CTGF (connective tissue growth factor), PDGFb (platelet growth factor-b), and TGF (transforming growth factor) family genes including TGFb1, TGFb2, and TGFb3, were significantly higher in sm-SOCS3-KO hearts than those in wild-type at 6 months of age.

Conclusion
Thus, smooth muscle cell-specific SOCS3 deletion induces increased pericardial fibrosis, cardiac interstitial fibrosis, and increased diastolic dysfunction in aging mice, possibly through the augmentation of pro-fibrotic growth factors.

Funding Acknowledgement
Type of funding source: Public grant(s) – National budget only. Main funding source(s): Grant JSPS KAKENHI
Mechanisms of endothelial cell activation by endocannabinoid 2-arachidonoylglycerol
Authors: Jehle J , Eich L , Avraamidou E , Tiyerili V , Bindila L , Lutz B , Nickenig G 
Published: November 2020

Abstract

Background
Endothelial dysfunction promotes atherogenesis, vascular inflammation, and thrombus formation. Reendothelialization after angioplasty is required in order to restore vascular function and to prevent stent thrombosis. The endocannabinoid (eCB) 2-arachidonoylglycerol (2-AG) is a known modulator of inflammation. Earlier studies have demonstrated the relevance of this endocannabinoid in human pathophysiology during coronary artery disease and in murine experimental atherogenesis. However, evidence on the impact of 2-AG on endothelial cell function remains scarce.

Methods
Endothelial repair was studied in two treatment groups of wildtype mice following electrical denudation of the common carotid artery. One group received the monoacylglycerol lipase (MAGL)-inhibitor JZL184, which impairs 2-AG degradation and thus causes elevated 2-AG levels, the other group received DMSO. The residual endothelial gap at five days was visualized by Evan's blue staining in either group. In vitro, the effect of 2-AG on human coronary artery endothelial cell (HCAEC) viability was assessed by an XTT-based assay. Endothelial activation was studied by an adhesion assay of THP-1 monocytes to 2-AG-preconditioned HCAEC. Activation of HCAEC adhesion molecules was characterized by flow cytometry.

Results
Elevated 2-AG levels significantly impaired reendothelialization in wildtype mice following electrical injury of the common carotid artery, resulting in a residual denudation at 5 days of 2291±286 μm vs. 1505±223 μm (n=18–19; p&lt;0.05). In vitro, 2-AG significantly reduced viability of HCAEC at 24 hours (0.31±0.10 vs. 1.00±0.08; n=3; p&lt;0.01). Finally, 2-AG promoted HCAEC activation resulting in a significant increase in THP-1 monocyte adhesion to HCAEC following pre-treatment of HCAEC with 2-AG (0.17±0.03 THP-1 cells per HCAEC vs. 0.07±0.01 THP-1 cells per HCAEC; n=3; p&lt;0.05). Adhesion molecules E-selectin, ICAM-1 and VCAM-1, that are known to be regulated by 2-AG in the venous endothelium, remained unchanged in arterial endothelial cells. Besides, HCAEC migration, ROS-production, expression of NADPH oxidases and secretion of inflammatory cytokines were unaffected by 2-AG.

Conclusion
Elevated 2-AG levels hamper endothelial repair and impair HCAEC proliferation while facilitating adhesion of monocytes. Intriguingly, the underlying mechanisms in the arterial vascular bed appear distinct from venous endothelium. Given that 2-AG is elevated during coronary artery disease in humans, 2-AG might impair reendothelialization after angioplasty and thus impact on clinical outcomes.

Funding Acknowledgement
Type of funding source: None
The role of B cells and IgG in aortic dissection
Authors: Nishida N , Furusho A , Aoki H , Ohno-Urabe S , Nishihara M , Hirakata S , Hayashi M , Ito S , Majima R , Hashimoto Y , Nakao E , Fukumoto Y 
Published: November 2020

Abstract

Background
Aortic dissection (AD) is one of the destructive and fatal aortic diseases, for which molecular pathogenesis is largely unknown. Recent studies have highlighted the importance of inflammatory response in AD. We and others reported that B cells and immunoglobulins participate in pathogenesis of abdominal aortic aneurysm, another form of aortic destructive disease, by promoting inflammatory response. It is not known whether and how B cells participate in AD pathogenesis.

Methods and results
Immunohistochemical staining of human AD tissue revealed that B cells were clustered together with T cells, macrophages and neutrophils at the entry site of AD with medial disruption. B cell cluster was also observed at the site of medial disruption in mouse model of AD that was induced by continuous infusion of beta-aminopropionitrile and angiotensin II (BAPN+AngII). In muMT mouse, which is deficient for B cells and immunoglobulins due to genetic deletion of immunoglobulin heavy chain, BAPN+AngII induced significantly less severe AD compared to that in wild type. Depositions of IgG and fibrinogen, one of the endogenous antigen for natural IgG, were observed after BAPN+AngII infusion before and after AD development in wild type mice. Deposition of fibrinogen was also observed in mMT mice after BAPN+AngII infusion. The rate of aortic rupture and sudden death was approximately 42% in wild type mice, while that in muMT mouse was 12% (P&lt;0.05). Administration of mouse normal polyclonal IgG to muMT mice resulted in dramatic increase in aortic rupture and sudden death, starting at day 7 of BAPN+AngII infusion, and reaching 69% of rupture rate, indicating the critical role of IgG in AD.

Conclusion
These findings demonstrated B cells and IgG are critically involved in the destructive inflammation of AD pathogenesis. Further, the deposition of fibrinogen, one of the targets of natural IgG, precedes the development of AD. Our findings may provide the conceptual foundation of the diagnostic strategy for on-going tissue destruction and for the therapeutic opportunities to intervene the progressive tissue destruction in AD.

Funding Acknowledgement
Type of funding source: Public grant(s) – National budget only. Main funding source(s): The Japan Society for the Promotion of Science
Nox2+ myeloid cells drive vascular inflammation and endothelial dysfunction in heart failure after myocardial infarction via angiotensin II receptor type 1
Authors: Molitor M , Rudi W.S , Garlapati V.S , Finger S , Wild J , Knopp T , Karbach S , Ruf W , Muenzel T , Wenzel P 
Published: November 2020

Abstract

Background
Ischemic heart failure (HF) ensuing myocardial infarction (MI) leads to impaired left ventricular function, reduced cardiac output and counterregulatory activation of angiotensin II (AngII) levels. Furthermore, it is characterized by the initiation of a systemic inflammatory response.

Objective
We aimed to elucidate the impact of myelomonocytic cells and their activation by angiotensin II on vascular endothelial function in a mouse model of HF after MI.

Results
HF was induced in male C57BL/6J mice by permanent ligation of the left anterior descending coronary artery. Compared to sham, HF mice had significantly impaired endothelial function accompanied by enhanced mobilization of Sca-1+c-Kit+ hematopoietic stem cells and Sca-1-c-Kit+ common myeloid and granulocyte-macrophage progenitors in the bone marrow as well as increased vascular infiltration of CD11b+Ly6G-Ly6Chigh monocytes and accumulation of CD11b+ F4/80+ macrophages, assessed by flow cytometry. Using mice with Cre-inducible expression of diphtheria toxin receptor in myeloid cells, we selectively depleted lysozyme M+ myelomonocytic cells for 10 d starting 28d after MI. While the cardiac phenotype remained unaltered until 38d post MI, myeloid cell depletion attenuated vascular accumulation of Nox2+CD45+ cells, endothelial dysfunction, oxidative stress and vascular expression of adhesion molecules and angiotensin II receptor type 1 (AT1R). Pharmacological blockade of this receptor for 4 weeks did not significantly alter cardiac function, but mimicked the effects of myeloid cell depletion: Telmisartan (20 mg/kg/d, fed to C57BL/6J mice) diminished bone marrow myelopoesis and myeloid ROS production, attenuated endothelial leukocyte rolling and vascular accumulation of CD11b+Ly6G-Ly6Chigh monocytes and macrophages, resulting in improved vascular function with less abundance of Nox2+CD45+ cells.

Conclusion
Endothelial dysfunction in HF ensuing MI is mediated by inflammatory Nox2+ myeloid cells infiltrating the vessel wall that can be targeted by AT1R blockade.

Funding Acknowledgement
Type of funding source: None
PHACTR1, a pro-atherosclerotic mechanosensitive PPARgamma corepressor in endothelial cells
Authors: Jiang D , Liu H , Zhu G , Li X , Fan L , Yu Z , Wang S , Rhen J , Yin Y , Gu Y , Xu X , Fisher E , Ge J , Xu Y , Pang J 
Published: November 2020

Abstract

Background
Numerous genome-wide association studies revealed that SNPs at phosphatase and actin regulator 1 (PHACTR1) locus are strongly correlated with coronary artery disease (CAD). However, the mechanism linking these variants to CAD remains uncertain.

Purpose
We studied the biological functions and molecular mechanisms of PHACTR1 in atherosclerosis.

Methods and results
Analysis of GTEx database showed that CAD-related SNPs in PHACTR1 are cis-eQTLs for PHACTR1 in arteries. Therefore, we generated Phactr1 knockout mice and crossed them with apolipoprotein E-deficient (ApoE−/−) mice to induce atherosclerosis by high-fat/high-cholesterol (HF-HC) diet. Phactr1 deficiency significantly inhibited atherosclerosis with decreased inflammatory cell infiltration. Western blot showed that PHACTR1 was restricted to endothelial cells (ECs) in mice. Mechanistically, RNAseq of aortic ECs revealed that the major molecular function of PHACTR1 was transcriptional regulation. PPARγ/RXRα was the top transcription factor, and PPARγ target gene expression substantially increased in Phactr1−/− mice. Moreover, we generated endothelial cell specific Phactr1−/−, ApoE−/− mice and found decreased atherosclerotic plaque area in aortic sinus. In vitro, PHACTR1 associated with PPARγ and inhibited PPARγ transcriptional activity. The inhibitory effect of PHACTR1 on PPARγ required its shuttling from cytosol to nucleus triggered by disturbed flow, a well-established pro-atherosclerotic stimulus.

Conclusion
Our results identified PHACTR1 as a mechanosensitive corepressor of PPARγ in ECs to promote atherosclerosis. Endothelial PHACTR1 is a potential therapeutic target for atherosclerosis treatment.

Funding Acknowledgement
Type of funding source: Public grant(s) – National budget only. Main funding source(s): National Natural Science Foundation of China (NSFC), China Postdoctoral Science Foundation (CPSF)