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Supplementary Figure Legend from Angiotensinogen Delays Angiogenesis and Tumor Growth of Hepatocarcinoma in Transgenic Mice

Angiotensinogen, a member of the serpin family, is involved in the suppression of tumor growth and metastasis. To investigate whether human angiotensinogen protects against tumor progression in vivo, we established an original bitransgenic model in which transgenic mice expressing human angiotensinogen (Hu-AGT-TG mice) were crossed with a transgenic mouse model of hepatocellular carcinoma (HCC-TG mice). Bitransgenic mice overexpressing human angiotensinogen (HCC/Hu-AGT-TG) had a significantly longer survival time than the HCC-TG mice and a reduction of both tumor growth and blood flow velocities in the liver. This antitumor effect of angiotensinogen is related to a reduced angiogenesis, impaired expression of endothelial arterial markers (active Notch4, Delta-like 4 ligand, and ephrin B2) with a decrease of arterial vessel density in HCC/Hu-AGT-TG mice liver. Overexpression of human angiotensinogen decreases angiogenesis, and prevents tumor sinusoids from remodeling and arterialization, thus delaying tumor progression in vivo. [Cancer Res 2009;69(7):2853–60]

Supplementary Figure 1 from Angiotensinogen Delays Angiogenesis and Tumor Growth of Hepatocarcinoma in Transgenic Mice

Dysregulated autophagy is associated with cardiovascular and metabolic diseases, where impaired flow-mediated endothelial cell responses promote cardiovascular risk. The mechanism by which the autophagy machinery regulates endothelial functions is complex. We applied multi-omics approaches and in vitro and in vivo functional assays to decipher the diverse roles of autophagy in endothelial cells. We demonstrate that autophagy regulates VEGF-dependent VEGFR signaling and VEGFR-mediated and flow-mediated eNOS activation. Endothelial ATG5 deficiency in vivo results in selective loss of flow-induced vasodilation in mesenteric arteries and kidneys, along with increased cerebral and renal vascular resistance. We found a crucial pathophysiological role for endothelial autophagy in flow-mediated outward arterial remodeling, prevention of neointima formation following wire injury, and recovery after myocardial infarction. Together, these findings unravel a fundamental role for autophagy in endothelial function, linking cell proteostasis to mechanosensing.

Enhancing the collateral blood supply during the acute phase of cerebral ischemia may limit both the extension of the core infarct, by rescuing the penumbra area, and the degree of disability. Many imaging techniques have been applied to rodents in preclinical studies, to evaluate the magnitude of collateral blood flow and the time course of responses during the early phase of ischemic stroke. The collateral supply follows several different routes at the base of the brain (the circle of Willis) and its surface (leptomeningeal or pial arteries), corresponding to the proximal and distal collateral pathways, respectively. In this review, we describe and illustrate the cerebral collateral systems and their modifications following pre-Willis or post-Willis occlusion in rodents. We also review the potential pharmaceutical agents for stimulating the collateral blood supply tested to date. The time taken to establish a collateral blood flow supply through the leptomeningeal anastomoses differs between young and adult animals and between different species and genetic backgrounds. Caution is required when transposing preclinical findings to humans, and clinical trials must be performed to check the added value of pharmacological agents for stimulating the collateral blood supply at appropriate time points. However, collateral recruitment appears to be a rapid, beneficial, endogenous mechanism that can be stimulated shortly after artery occlusion. It should be considered a treatment target for use in addition to recanalization strategies.

International audience; Ischemia is a common cause of acute kidney injury worldwide, frequently occurring in patients undergoing cardiac surgery or admitted to the intensive care unit (ICU). Thus, ischemia-reperfusion injury (IRI) remains one of the main experimental models for the study of kidney diseases. However, the classical technique, based on non-traumatic surgical clamps, suffers from several limitations. It does not allow the induction of multiple episodes of acute kidney injury (AKI) in the same animal, which would be relevant from a human perspective. It also requires a deep and long sedation, raising the question of potential anaesthesia-related biases. We designed a vascular occluding device that can be activated remotely in conscious mice. We first assessed the intensity and the reproducibility of the acute kidney injury induced by this new device. We finally investigated the role played by the anaesthesia in the IRI models at the histological, functional and transcriptomic levels. We showed that this technique allows the rapid induction of renal ischemia in a repeatable and reproducible manner, breaking several classical limitations. In addition, we used its unique specificities to highlight the renal protective effect conferred by the anaesthesia, related to the mitigation of the IRI transcriptomic program.

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The poly(ADP-ribose) polymerase inhibitor PJ34 has recently been reported to increase cerebral blood flow, via the endothelial NO synthase, in the naive mouse brain throughout life. We addressed here the benefits of PJ34 after neonatal ischemia on hemodynamics and components of the neurovascular unit including the blood-brain barrier (BBB), microglia, and astrocytes. Nine-day-old mice were subjected to permanent MCA occlusion (pMCAo), and treated with either PBS or PJ34 (10 mg/kg). Mean blood-flow velocities (mBFV) were measured in both internal carotid arteries (ICA) and basilar trunk (BT) using Doppler-ultrasonography. BBB opening was assessed through somatostatin-receptor type-2 internalization and immunohistochemistry at 24 and 48 h. Lesion areas were measured 8 days after ischemia. In PBS-treated mice, pMCAo involved a drop in mBFV in the left ICA (p &lt, 0.001 vs. basal), whereas mBFV remained stable in both right ICA and BT. PJ34 prevented this drop in the left ICA (NS vs. basal) and increased mBFV in the right ICA (p = 0.0038 vs. basal). No modification was observed in the BT. In contrast to PBS, BBB disruption extent and astrocyte demise were reduced in PJ34 mice only in the rostral brain at 48 h and 8 days post-pMCAo, respectively. Accordingly, 8 days after pMCAo, affected areas were reduced in the rostral brain (Bregma +0.86 and +0.14 mm), whereas total tissue loss was not reduced after PJ34 (4.0 ± 3.1%) vs. PBS (5.8 ± 3.4%). These results show that PJ34 reduced BBB permeability, astrocyte demise, and tissue loss (particularly in the rostral territories), suggesting that collateral supply mainly proceeds from the anterior ICA’s branches in the ischemic neonatal mouse brain.

Rationale: Cerebrovascular function is critical for brain health, and endogenous vascular protective pathways may provide therapeutic targets for neurological disorders. S1P (Sphingosine 1-phosphate) signaling coordinates vascular functions in other organs, and S1P 1 (S1P receptor-1) modulators including fingolimod show promise for the treatment of ischemic and hemorrhagic stroke. However, S1P 1 also coordinates lymphocyte trafficking, and lymphocytes are currently viewed as the principal therapeutic target for S1P 1 modulation in stroke. Objective: To address roles and mechanisms of engagement of endothelial cell S1P 1 in the naive and ischemic brain and its potential as a target for cerebrovascular therapy. Methods and Results: Using spatial modulation of S1P provision and signaling, we demonstrate a critical vascular protective role for endothelial S1P 1 in the mouse brain. With an S1P 1 signaling reporter, we reveal that abluminal polarization shields S1P 1 from circulating endogenous and synthetic ligands after maturation of the blood-neural barrier, restricting homeostatic signaling to a subset of arteriolar endothelial cells. S1P 1 signaling sustains hallmark endothelial functions in the naive brain and expands during ischemia by engagement of cell-autonomous S1P provision. Disrupting this pathway by endothelial cell-selective deficiency in S1P production, export, or the S1P 1 receptor substantially exacerbates brain injury in permanent and transient models of ischemic stroke. By contrast, profound lymphopenia induced by loss of lymphocyte S1P 1 provides modest protection only in the context of reperfusion. In the ischemic brain, endothelial cell S1P 1 supports blood-brain barrier function, microvascular patency, and the rerouting of blood to hypoperfused brain tissue through collateral anastomoses. Boosting these functions by supplemental pharmacological engagement of the endothelial receptor pool with a blood-brain barrier penetrating S1P 1 -selective agonist can further reduce cortical infarct expansion in a therapeutically relevant time frame and independent of reperfusion. Conclusions: This study provides genetic evidence to support a pivotal role for the endothelium in maintaining perfusion and microvascular patency in the ischemic penumbra that is coordinated by S1P signaling and can be harnessed for neuroprotection with blood-brain barrier-penetrating S1P 1 agonists.

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Acute myocardial infarction (MI) is a common condition responsible for heart failure and sudden death. Here, we show that following acute MI in mice, CD8+ T lymphocytes are recruited and activated in the ischemic heart tissue, and release Granzyme B leading to cardiomyocyte apoptosis, adverse ventricular remodeling and deterioration of myocardial function. Depletion of CD8+ T lymphocytes decreases apoptosis within the ischemic myocardium, hampers inflammatory response, limits myocardial injury and improves heart function. These effects are recapitulated in mice with Granzyme B-deficient CD8+ T cells. The protective effect of CD8 depletion on heart function was confirmed by using a model of ischemia/reperfusion in pigs. Finally, we reveal that elevated circulating levels of Granzyme B in patients with acute MI predict increased risk of death at 1-year follow-up. Our work unravels an unsuspected deleterious role of CD8+ T lymphocytes following acute ischemia, and identifies novel therapeutic strategy targeting pathogenic CD8+ T lymphocytes in the setting of acute MI.

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Acute myocardial infarction is a common condition responsible for heart failure and sudden death. Here, we show that following acute myocardial infarction in mice, CD8+ T lymphocytes are recruited and activated in the ischemic heart tissue and release Granzyme B, leading to cardiomyocyte apoptosis, adverse ventricular remodeling and deterioration of myocardial function. Depletion of CD8+ T lymphocytes decreases apoptosis within the ischemic myocardium, hampers inflammatory response, limits myocardial injury and improves heart function. These effects are recapitulated in mice with Granzyme B-deficient CD8+ T cells. The protective effect of CD8 depletion on heart function is confirmed by using a model of ischemia/reperfusion in pigs. Finally, we reveal that elevated circulating levels of GRANZYME B in patients with acute myocardial infarction predict increased risk of death at 1-year follow-up. Our work unravels a deleterious role of CD8+ T lymphocytes following acute ischemia, and suggests potential therapeutic strategies targeting pathogenic CD8+ T lymphocytes in the setting of acute myocardial infarction., Immune cells contribute to adverse remodeling following myocardial infarction. Here the authors show in mice and pigs that CD8+ lymphocytes release Granzyme B in the infarcted heart leading to cardiomyocyte death, enhanced inflammation and deterioration of cardiac function.

Patients with severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) pneumonia with SARS-CoV-2 present with coagulation disorders and marked susceptibility to thrombosis ([1][1],[2][2]). However, the exact prevalence of deep vein thrombosis (DVT) has been poorly investigated, although the risk

The endothelin system may be an important player in hypertensive end-organ injury as endothelin-1 increases blood pressure and is pro-inflammatory. The immune system is emerging as an important regulator of blood pressure and we have shown that the early hypertensive response to angiotensin-II infusion was amplified in mice deficient of myeloid endothelin-B (ETB) receptors (LysM-CreEdnrblox/lox). Hypothesizing that these mice would display enhanced organ injury, we gave angiotensin-II to LysM-CreEdnrblox/lox and littermate controls (Ednrblox/lox) for six weeks. Unexpectedly, LysM-CreEdnrblox/lox mice were significantly protected from organ injury, with less proteinuria, glomerulosclerosis and inflammation of the kidney compared to controls. In the eye, LysM-CreEdnrblox/lox mice had fewer retinal hemorrhages, less microglial activation and less vessel rarefaction. Cardiac remodeling and dysfunction were similar in both groups at week six but LysM-CreEdnrblox/lox mice had better endothelial function. Although blood pressure was initially higher in LysM-CreEdnrblox/lox mice, this was not sustained. A natriuretic switch at about two weeks, due to enhanced ETB signaling in the kidney, induced a hypertensive reversal. By week six, blood pressure was lower in LysM-CreEdnrblox/lox mice than in controls. At six weeks, macrophages from LysM-CreEdnrblox/lox mice were more anti-inflammatory and had greater phagocytic ability compared to the macrophages of Ednrblox/lox mice. Thus, myeloid cell ETB receptor signaling drives this injury both through amplifying hypertension and by inflammatory polarization of macrophages., Graphical abstract

Background Curative surgery of synchronous peritoneal metastases (PM) and colorectal liver metastases (LM) has been recently investigated as feasible option. When synchronous peritoneal and liver resection is not achievable, the sequence of the surgery remains unknown. Our hypothesis was that liver resection (LR) promotes peritoneal growth resulting in a non-resectable PM. We sought to analyse the effects of major LR and liver regeneration after hepatectomy in a murine model of PM and the associated angiogenesis. Methods Murine model of colorectal PM in Balb/C mice was developed by intraperitoneal injection of different CT-26 tumour cell concentrations. Five days after the injection, mice were randomized into three groups: 68% hepatectomy group, sham laparotomy and control group without surgery. On post-operative days 1, 5 and 20, PM was evaluated macroscopically, tumour growth and liver regeneration by immunohistochemistry, and angiogenesis by immunofluorescence. Circulating progenitor cells, plasmatic cytokines and digestive arterial blood flow velocity measurements were also analysed. Results Reproducible murine model of limited colorectal PM was obtained. Surgery induced PM increases and promoted neo-angiogenesis. Major hepatectomy influence the tumour growth in the late phase after surgery, the extent of extra-peritoneal metastasis and the increase of Ki-67 expression in the remnant liver. Conclusions This animal model confirms the pro-tumoural and pro-angiogenic role of surgery, laparotomy and major LR, which promotes the increase of angiogenic factors and their participation in PM growth. These results suggest that peritoneal resection should be first step in the case of two-step liver and peritoneal surgery for patients with colorectal PM and LM.

Circulatory failure following cardiac arrest (CA) requires catecholamine support and occasionally veno-arterial extracorporeal membrane oxygenation (vaECMO). VaECMO-generated blood flow is continuous and retrograde, increasing ventricular stroke work. Our aim was to assess the benefit of a device generating a pulsatile vaECMO flow synchronized with the heart rhythm lowering systolic vaECMO output on the left ventricular ejection fraction (LVEF) and pulmonary capillary pressure (Pcap) after CA. This experimental randomized study in pigs compared standard nonpulsatile vaECMO (control) with pulsatile synchronized vaECMO (study) group using a pulsatility-generating device. After sedation and intubation, ventricular fibrillation was induced by pacing. After 10-min ventricular fibrillation, cardiopulmonary resuscitation was performed for 20 min then vaECMO, defibrillation and 0.15 µg/kg/min intravenous epinephrine infusion were initiated. Hemodynamics, Pcap, LVEF by echocardiography and angiography were measured at baseline and every 30 min after the vaECMO start until vaECMO and epinephrine were stopped (at 120 min), and 30 min later. Baseline hemodynamics did not differ between groups; 120 min after vaECMO initiation, LVEF by echocardiography and angiography was significantly higher in the study than control group 55 ± 19% versus 34 ± 13% (P = 0.042), 50 ± 16% versus 33 ± 12% (P = 0.043), respectively. Pcap decreased from baseline by 4.2 ± 8.6 mm Hg in the study group but increased by 5.6 ± 5.9 mm Hg in the control group (P = 0.043). Thirty minutes later, LVEF remained higher in the study group 44 ± 7% versus 26 ± 11% (P = 0.008) while Pcap did not differ. A synchronized pulsatile device decreasing systolic output from vaECMO improved LVEF and Pcap in a pig model of CA and resuscitation.

Introduction L’ischemie renale est une cause frequente d’insuffisance renale aigue (IRA) chez l’homme. C’est pourquoi l’ischemie-reperfusion (IR) est un modele d’IRA couramment utilise chez les rongeurs. La procedure classique pour induire l’IR chez la souris repose sur le clampage unilateral ou bilateral du pedicule vasculaire renal avec un clamp non traumatique sous anesthesie generale. Cependant, la gravite des lesions induites par cette procedure depend fortement non seulement de la duree de l’ischemie mais aussi d’autres parametres (le serrage du clamp, la profondeur de l’anesthesie et le degre d’hypothermie induite par l’anesthesie). Une autre limite importante reside dans le fait qu’elle ne peut pas etre utilisee pour induire plusieurs episodes d’IR chez le meme animal. Description Nous avons concu un nouvel outil pour induire des ischemies multiples pendant une duree precise chez la souris vigile. Methodes L’utilisation de segments de tubes de silicone souple montes sur un simple fil tisse, dont les extremites sont maintenues a la surface de la peau de la souris, nous a permis de repondre a ces exigences. Nous avons nomme ce dispositif le clamp RIRI, pour « Repeated Ischemia-Reperfusion Injury ». Apres avoir constate que l’ischemie sur souris vigiles induit des lesions plus importantes que sur souris anesthesiees, nous avons cherche a comprendre les mecanismes sous-jacents par comparaison des transcriptomes (RNA-seq). Resultats Nous avons montre que l’IR induit des lesions renales plus severes chez les animaux vigiles que chez les animaux anesthesies. Nous avons ensuite teste l’influence potentielle de la temperature corporelle, du stress et du metabolisme grâce a la comparaison des transcriptomes, obtenus par RNA-seq, des reins ischemiques de souris anesthesiees et vigiles. Conclusion Notre etude met ainsi en evidence pour la premiere fois les consequences de l’anesthesie sur le developpement de la lesion ischemique renale, ouvrant la voie a de futures decouvertes dans le domaine de la nephroprotection perioperatoire.

Introduction La COVID-19 est associee a un risque eleve d’evenement thromboembolique veineux (ETEV), thrombose veineuse profonde (TVP) et/ou embolie pulmonaire (EP) en particulier chez les patients hospitalises. Objectifs Caracteriser le desequilibre de la balance hemostatique chez ces patients et decrire la prise en charge et l’evolution a 6 mois des patients avec ETEV. Methodes Etude prospective incluant des patients consecutifs hospitalises en reanimation ou en medecine pour COVID-19, avec : – un echo-Doppler veineux systematique a l’admission en reanimation puis 7 jours plus tard en cas de negativite et en cas de symptomes de TVP en service de medecine ; – un angioscanner thoracique realise en cas de suspicion d’EP ; – un bilan d’hemostase realise a l’admission ; – le suivi des patients ayant presente un ETEV a 1, 3 et 6 mois afin de colliger les evenements thrombotiques et hemorragiques. Resultats Du 17.03 au 11.04.2020, 133 patients d’âge median 65 ans (72 % hommes) ont ete hospitalises pour COVID-19. Trente-huit patients ont presente un ETEV (63 % TVP, 24 % EP, 13 % TVP + EP) dont 9 sont decedes pendant l’hospitalisation, 2 ont ete transferes et 26 suivis. Nos resultats montrent : – un taux de D-dimeres > 3300 ng/mL predictif d’un ETEV avec une VPP 66 % (IC95 % : 51–79) et VPN 80 % (IC95 % : 65–90) en reanimation ; – une discordance significative entre les activites anticoagulante/chromogenique de la proteine C (p = .002 chez les patients ETEV+) evocatrice d’une resistance acquise a la proteine C activee ; – une association entre les taux de facteur Willebrand et d’ADAMTS13 et les ETEV (p = .05 et p = .005 respectivement) d’une part et entre les taux d’ADAMTS13/D-dimeres et la mortalite d’autre part ; – des anticorps antiphospholipides presents chez 88 % des patients en reanimation, non associes a la survenue d’ETEV. Les 26 patients suivis avec ETEV ont ete traites par apixaban (22), rivaroxaban (2) ou tinzaparine (2) durant 3 a 6 mois. Un infarctus du myocarde et 2 saignements mineurs ont ete recenses. Aucune recidive d’ETEV n’a ete observee. Conclusions La frequence elevee d’ETEV chez les patients hospitalises pour COVID-19 est associee a un profil biologique de thrombo-inflammation, avec un desequilibre marque entre facteurs prothrombotiques/inhibiteurs naturels de la coagulation et de l’axe VWF/ADAMTS13. Le traitement par anticoagulant oral direct est une option therapeutique possible pour le traitement d’un ETEV lie a une hospitalisation pour COVID-19.

L’epave d’un bateau medieval a ete decouverte dans la Seine a Fontaine-le-Port en 2015, au cours d’une operation de prospection archeologique subaquatique dans un secteur ou des structures s’apparentant a un amenagement meunier medieval avaient deja ete observees. Le bateau est integralement recouvert par un remblai de pierres et de graviers, entretenu naturellement par la configuration de la rive qui produit un tourbillon a l’origine de son enfouissement et qui l’a miraculeusement protege ju...

Background After incomplete cytoreductive surgery (CRS), the assessment of pseudomyxoma peritonei (PMP) progression remains challenging. The objective was to assess the efficacy of wall shear stress (WSS) measured in superior mesenteric artery (SMA) to predict PMP progression in the postoperative setting to propose additional treatments. Methods In a prospective study, 52 patients with PMP had Doppler-ultrasound examination of the SMA with WSS calculation within one year after CRS with a mean follow-up of 43.3 ± 18.3 months. Patients were categorized according to the completeness of CRS and clinical outcome: Group-1 (n = 19): complete CRS and no recurrence, group-2 (n = 20): incomplete CRS with slowly progressive disease (alive at 2 years without severe clinical symptoms), group-3 (n = 13): incomplete CRS and severe clinical symptoms or dead within two years. Results of WSS were compared between groups and to 24 healthy subjects. Results WSS measured in the SMA was superior in Group-3 (19.6 ± 8.2 dynes/cm2) than in Group-2 (9.2 ± 1.8 dynes/cm2, p = 1.10−6), Group-1 (10.4 ± 2.8 dynes/cm2, p = 8.10−5), and healthy patients (8.7 ± 2.8 dynes/cm2, p = 9.10−7). One year after surgery, among patients with incomplete CRS a cut-off value of 12.1dynes/cm2 allowed distinguishing patients without from those with severe disease progression with a sensitivity of 100% and a specificity of 100% (p Conclusion Post-operative assessment of the WSS in the SMA in patients with incomplete CRS for PMP should be considered as biomarker of tumor progression in the postoperative setting. Therefore, WSS could be useful to target patients needing adjuvant systemic chemotherapy one year after CRS.

Background: Defective systemic and local iron metabolism correlates with cardiac disorders. Hepcidin, a master iron sensor, actively tunes iron trafficking. We hypothesized that hepcidin could play a key role to locally regulate cardiac homeostasis after acute myocardial infarction. Methods: Cardiac repair was analyzed in mice harboring specific cardiomyocyte or myeloid cell deficiency of hepcidin and challenged with acute myocardial infarction. Results: We found that the expression of hepcidin was elevated after acute myocardial infarction and the specific deletion of hepcidin in cardiomyocytes failed to improve cardiac repair and function. However, transplantation of bone marrow–derived cells from hepcidin-deficient mice ( Hamp −/− ) or from mice with specific deletion of hepcidin in myeloid cells (LysM CRE/+ / Hamp f/f ) improved cardiac function. This effect was associated with a robust reduction in the infarct size and tissue fibrosis in addition to favoring cardiomyocyte renewal. Macrophages lacking hepcidin promoted cardiomyocyte proliferation in a prototypic model of apical resection–induced cardiac regeneration in neonatal mice. Interleukin (IL)–6 increased hepcidin levels in inflammatory macrophages. Hepcidin deficiency enhanced the number of CD45 + /CD11b + /F4/80 + /CD64 + /MHCII Low /chemokine (C–C motif) receptor 2 (CCR2) + inflammatory macrophages and fostered signal transducer and activator of transcription factor-3 (STAT3) phosphorylation, an instrumental step in the release of IL-4 and IL-13. The combined genetic suppression of hepcidin and IL-4/IL-13 in macrophages failed to improve cardiac function in both adult and neonatal injured hearts. Conclusions: Hepcidin refrains macrophage-induced cardiac repair and regeneration through modulation of IL-4/IL-13 pathways.

Ngkelo et al. use a mast cell–deficient mouse model to reveal a protective role of mast cells in myocardial infarction, through regulation of the cardiac contractile machinery., Acute myocardial infarction (MI) is a severe ischemic disease responsible for heart failure and sudden death. Inflammatory cells orchestrate postischemic cardiac remodeling after MI. Studies using mice with defective mast/stem cell growth factor receptor c-Kit have suggested key roles for mast cells (MCs) in postischemic cardiac remodeling. Because c-Kit mutations affect multiple cell types of both immune and nonimmune origin, we addressed the impact of MCs on cardiac function after MI, using the c-Kit–independent MC-deficient (Cpa3Cre/+) mice. In response to MI, MC progenitors originated primarily from white adipose tissue, infiltrated the heart, and differentiated into mature MCs. MC deficiency led to reduced postischemic cardiac function and depressed cardiomyocyte contractility caused by myofilament Ca2+ desensitization. This effect correlated with increased protein kinase A (PKA) activity and hyperphosphorylation of its targets, troponin I and myosin-binding protein C. MC-specific tryptase was identified to regulate PKA activity in cardiomyocytes via protease-activated receptor 2 proteolysis. This work reveals a novel function for cardiac MCs modulating cardiomyocyte contractility via alteration of PKA-regulated force–Ca2+ interactions in response to MI. Identification of this MC-cardiomyocyte cross-talk provides new insights on the cellular and molecular mechanisms regulating the cardiac contractile machinery and a novel platform for therapeutically addressable regulators.

Background: Non-alcoholic fatty liver disease (NAFLD), especially non-alcoholic steatohepatitis (NASH) is a chronic liver disease commonly associated with hepatic fibrosis. NASH patients have an increased risk for hepatocellular carcinoma (HCC). Due to western way of life, NASH incidence is rising and predicted to become the leading cause of liver transplant in 2020 and of HCC in the next decades. There is an urgent need for robust animal models fully recapitulating the NASH-related HCC carcinogenesis due to this changing in HCC etiology. In this study, we develop and characterize specific diet-induced variants from our transgenic HCC mouse model, focusing on immune landscape. Methods: We used in the whole study ASV-B mice: a transgenic mouse model (C57BL/6J) spontaneously developing a reproducible stage-defined HCC (hyperplasia at week(W)8, nodular stage at W12, and diffuse carcinoma at W16-20). Livers were characterized for angiogenesis and immune populations using immunostaining (IHC and IF), and qRT-PCR (LightCycler, Roche). To mimic NASH, ASV-B mice were exposed to 5 different diets. Ten ASV-B and 5 control mice were fed as follows: classic diet as control (yellow), or a high-fat diet (blue), a diet enriched with saturated fatty acids + 1.25% cholesterol (green), a diet containing 22% of vegetal oil + 0.2% cholesterol (orange), and a 1.25% cholesterol diet containing 21% of milkfat (red). All mice fed with special diets also received 30% fructose in the drink water. A second experiment was performed on ASV-B and C57BL/6J wild type mice, using control and Nash-inducing regimen, to confirm our first results. Results: ASV-B model showed an increase in liver volume and angiogenesis, HCC livers harboring marked arterialization and capillarization as compared to control. Assessing immune markers on 7 evaluable tumor specimens, we observed an increase in CD8, Foxp3, INOS, CD11b, PD-1, PD-L1, IL1β, IFN-γ, TNF-α, IL17A and IL17F mRNA expressions, as frequently observed in human inflammatory HCC. In addition, IHC staining showed intratumoral infiltration of lymphocytes (CD8+) and macrophages (F4/80+, a well-characterized and extensively referenced mouse macrophage marker). ASV-B mice receiving yellow, blue, and green regimens showed similar liver volumes and weights. By macroscopic analysis, we observed increased liver steatosis, and fibrosis in the red and orange regimen compared to others. Moreover, we observed a 40% mortality rate in the orange regimen, and a 20% mortality rate in the blue and green regimens. Interestingly, by microscopic analysis, we observed liver steatosis and inflammation, in 100%, and 75% of the mice, respectively. These results indicate that the green regimen is the most suitable to induce NASH-underlyning disease in our transgenic HCC model. At the conference, we will show in the diet-variants, the immune landscape of the livers and the results of our ongoing second experiment. Conclusion: ASV-B transgenic mouse model mimics several characteristics of human HCC developing on healthy liver including inflammatory reaction and immune cell infiltration. In the ASV-B model, we have been able to develop specific-diets variants mimicking NASH characteristics that could be used for drug testing. Citation Format: Annemilaï Tijeras-Raballand, Christian Hobeika, Philippe Bonnin, Benoit Rousseau, Aurélie Rodrigues, Fouad Ladfil, Marc Pocard, Armand de Gramont, Eric Raymond, Sandrine Faivre, Valérie Paradis, Clarisse Eveno. Diet-variants and immune characterization of a stage-defined, transgenic immunocompetent mouse model of HCC (ASV-B) [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 1636.

To assess the prognostic value of the wall shear stress (WSS) measured in the feeding native arteries upstream from facial superficial arteriovenous malformations (sAVMs). Reliable prognostic criteria are needed to distinguish progressive from stable sAVMs and thus support the indication for an aggressive or a conservative management to avoid severe facial disfigurement. We prospectively included 25 patients with untreated facial sAVMs, 15 patients with surgically resected sAVMs and 15 controls. All had undergone Doppler ultrasound examination (DUS) with measurements of inner diameters, blood flow velocities, computation of blood flow and WSS of the feeding arteries. Based on the absence or presence of progression in clinical and imaging examinations 6 months after, we discriminated untreated patients as stable or progressive. WSS in the ipsilateral external carotid artery was higher in progressive compared to stable sAVMs (15.8 ± 3.3dynes/cm² vs. 9.6 ± 2.0dynes/cm², mean±SD, p 0.0001) with a cut-off of 11.5dynes/cm² (sensitivity: 92 %, specificity: 92 %, AUC: 0.955, [95 %CI: 0.789-0.998], p = 0.0001). WSS in the ipsilateral facial artery was also higher in progressive compared to stable sAVMs (50.7 ± 14.5dynes/cm² vs. 25.2 ± 7.1dynes/cm², p 0.0001) with a cut-off of 34.0dynes/cm² (sensitivity: 100 %, specificity: 92 %, AUC: 0.974, [95 %CI: 0.819-1.000], p = 0.0001). The hemodynamic data of operated patients were not different from those of the control group. WSS measured in the feeding arteries of an sAVM may be a simple reliable criterion to distinguish stable from progressive sAVMs. This value should be considered to guide the therapeutic strategy as well as the long-term follow-up of patients with facial sAVMs.ZIEL: Beurteilung des prognostischen Wertes der Wandschubspannung (WSS), gemessen in den zuführenden nativen Arterien stromaufwärts von oberflächlichen arteriovenösen Fehlbildungen des Gesichts (sAVMs). Um progressive von stabilen sAVMs zu unterscheiden sind verlässliche prognostische Kriterien erforderlich, die bei der Indikation für eine aggressive oder konservative Behandlung hilfreich sind, um schwere Gesichtsdeformierungen zu vermeiden. Prospektiv wurden 25 Patienten mit unbehandelten sAVMs im Gesicht, 15 Patienten mit chirurgisch-resezierten sAVMs und 15 Kontrollpatienten eingeschlossen. Alle hatten eine Doppler-Ultraschalluntersuchung (DUS) mit Bestimmungen der Innendurchmesser, Blutflussgeschwindigkeiten, Berechnung des Blutflusses und der WSS der zuführenden Arterien. Aufgrund des Fehlens oder Auftretens einer Progression bei den klinischen und bildgebenden Untersuchungen nach 6 Monaten unterschieden wir unbehandelte Patienten als stabil oder progressiv. WSS in der ipsilateralen A. carotis externa war bei progressiven sAVMs im Vergleich zu stabilen sAVMs höher (15,8 ± 3,3 dyn/cm² vs. 9,6 ± 2,0 dyn/cm², Mittelwert±SD, p 0,0001) mit einem Cut-off von 11,5 dyn/cm² (Sensitivität: 92 %, Spezifität: 92 %, AUC: 0,955, [95 %CI: 0,789–0,998], p = 0,0001). WSS in der ipsilateralen A. facialis war ebenfalls höher bei den progressiven im Vergleich zu den stabilen sAVMs (50,7 ± 14,5 dyn/cm² vs. 25,2 ± 7,1 dyn/cm², p 0,0001) mit einem Cut-off von 34,0 dyn/cm² (Sensitivität: 100 %, Spezifität: 92 %, AUC: 0,974, [95 %CI: 0,819–1,000], p = 0,0001). Die hämodynamischen Daten operierter Patienten unterschieden sich nicht von denen der Kontrollgruppe. WSS, gemessen in den zuführenden Arterien eines sAVM, kann ein einfache zuverlässiges Kriterium sein, um stabile von progressiven sAVMs zu unterscheiden. Dieser Wert sollte als Richtschnur für die therapeutische Strategie sowie für die langfristige Nachsorge von Patienten mit sAVM im Gesicht angesehen werden.

International audience; The pathophysiology of sporadic Alzheimer's disease (AD) remains uncertain. Along with brain amyloid-β (Aβ) deposits and neurofibrillary tangles, cerebrovascular dysfunction is increasingly recognized as fundamental to the pathogenesis of AD. Using an experimental model of limb ischemia in transgenic APPPS1 mice, a model of AD (AD mice), we showed that microvascular impairment also extends to the peripheral vasculature in AD. At D70 following femoral ligation, we evidenced a significant decrease in cutaneous blood flow (- 29%, P

To analyze optical coherence tomography angiography images of retinal capillary perfusion in incomplete central retinal artery occlusion.Case report of a 63-year-old male white patient with transient vision loss in the left eye related to central retinal artery occlusion, secondary to left internal carotid thrombosis. Optical coherence tomography angiography images were captured with Angiovue (Optovue, Inc., Freemont, CA). Retinal capillary bed was segmented into the superficial and deep capillary plexus. Each blood flow angiography image was associated with an en face optical coherence tomography image and an optical coherence tomography B-scan showing the level of segmentation.In the left eye, visual acuity was 20/20 five days after transient vision loss. Optical coherence tomography angiography showed a normal superficial capillary plexus but the deep capillary plexus was not distinguishable compared with the right eye, although the posterior pole appeared well perfused on fluorescein angiography. Retrobulbar Doppler ultrasound confirmed a reduced blood flow velocity in the left central retinal artery.In this case of incomplete and transient central retinal artery occlusion, the deep capillary plexus was poorly visible on optical coherence tomography angiography, which could be due to its elective hypoperfusion and explain the ischemic whitening of the inner nuclear layer, previously described as paramacular acute middle maculopathy. However, the reason why the deep capillary plexus is more sensitive to reduced blood flow in the central retinal artery is not fully understood. In a case of partial central retinal artery occlusion, optical coherence tomography angiography allowed showing elective poor perfusion of the retinal deep capillary plexus.

The epidemiological link between hypertension and Alzheimer disease is established. We previously reported that hypertension aggravates the Alzheimer-like pathology in APPPS1 mice (amyloid precursor protein/presenilin-1, mouse model of Alzheimer disease) with angiotensin II–induced hypertension, in relation with hypertension and nitric oxide deficiency. To provide further insights into the role of nitric oxide in the hypertension—Alzheimer disease cross-talk, we studied the effects of nitric oxide blockade in APPPS1 mice using N (ω)-nitro- l -arginine methyl ester ( l -NAME) alone or in combination with hydralazine, to normalize blood pressure. Compared with normotensive APPPS1 mice, those with l -NAME–induced hypertension had greater amyloid burden ( P P P P l -NAME–induced deterioration except for cortical amyloid angiopathy, linked to hypertension-induced arterial wall remodeling. By testing the cerebrovascular response to hypercapnic breathing, we evidenced early functional impairment of cerebral vasomotor activity in APPPS1 mice. Whereas in control wild-type normotensive mice, carbon dioxide breathing resulted in 15±1.3% increase in the mean blood flow velocity ( P P l -NAME–treated hypertensive APPPS1 mice (2.5±1.2%) and partly reversed to mild vasodilation by hydralazine (3.2±1.5%, P l -NAME–induced hypertension. Only cerebral amyloid angiopathy seems to be dependent on hypertension.

To examine whether pulmonary artery balloon pulsation (PABP) could improve circulatory function in acute myocardial infarction (AMI) in pigs.Ten downsize pigs were sedated and ventilated. AMI was induced by inserting a plug into the left anterior descending artery. A pulsation balloon was placed in the pulmonary artery in all animals. In the treatment group (TG), pulsations began when life-threatening arrhythmia or30% drop in mean blood pressure (MBP) or40% decrease in cardiac output compared to baseline occurred. Pulsation rate was 120/min, independent of the heartbeat, maintained for 10 min. The control group (CG) received no pulsation. In the TG (n = 5), mean BP after the AMI improved by 7 ± 12 mmHg after 150 min while in the CG, MBP decreased by 17 ± 25 mmHg, P0.05; coronary perfusion pressure improved by 8 ± 7 mmHg in the TG but decreased by 15 ± 12 in the CG (P0.05). In the CG, cardiac output did not change but in the TG it improved from 3.5 ± 0.9 after the AMI to 4.2 ± 1.1 l/min 150 min after AMI (P0.05). The TG required 1.8 ± 0.4 electric shocks for ventricular fibrillation versus 0.8 ± 0.4 in the pulsation group (P0.05).PABP could be useful in the management of AMI due to improved mean arterial BP, coronary perfusion pressure, cardiac output and electrical stability. The mechanism of this effect remains to be determined.

Background Pseudomyxoma peritonei (PMP) is a rare carcinomatosis limited to the peritoneal cavity, mainly supplied by the superior mesenteric artery (SMA). The only curative treatment is cytoreductive surgery (CRS) associated with hyperthermic intraperitoneal chemotherapy. This study aimed to evaluate the ability of blood flow volume (BFV) recorded in the SMA using Doppler ultrasonography pre-operatively to predict the extent and resectability of the disease and post-operatively to assess clinical outcome. Methods BFV was measured in the SMA of forty-nine patients before and the year following CRS. Patients were categorized in 3 groups according to clinical and surgical outcomes: group-1 (n = 22): patient with completed CRS, group-2 (n = 16): incomplete resection with slowly progressive disease (alive at 2 years without severe clinical symptoms), group-3 (n = 11): incomplete resection and with severe clinical symptoms or dead within two years. Results Pre-operative mean SMA BFV was higher in group-2 (510 mL/min, p = 0.027) and in group-3 (572 mL/min, p = 0.004) than in group-1 (378 mL/min). After surgery, BFV dropped to normal values (203 mL/min, p = 0.001) in group-1, and to 423 mL/min (p = 0.047) in group-2. It remained elevated in group-3 (626 mL/min, p = 0.566). BFV allowed stratification of 1) resectability before CRS (group-2 and -3 vs group-1, area under the ROC curve: 0.794 [0.650–0.939]), and 2) non progression after incomplete CRS (group-3 vs group-2, area under the ROC curve: 0.827 [0.565–1.00]. Conclusions Pre-operative BFV in the SMA correlates with extent and resectability of PMP. After incomplete surgery, post-operative BFV might aid in identifying patients who may benefit of post-operative therapy.

Perinatal arterial stroke is the most frequent form of cerebral infarction in children. Neonatal seizures are the most frequent symptom during the neonatal period. The current management of perinatal stroke is based on supportive care. It is currently unknown if treatment of the seizures modifies the outcome, and no clinical studies have focused on seizures during neonatal stroke. We studied the effect of phenobarbital and levetiracetam on an ischemic-reperfusion stroke model in P7 rats using prolonged electroencephalographic recordings and a histologic analysis of the brain (24 h after injury). The following two types of epileptic events were observed: 1) bursts of high amplitude spikes during ischemia and the first hours of reperfusion and 2) organized seizures consisting in discharges of a 1–2 Hz spike-and-wave. Both phenobarbital and levetiracetam decreased the total duration of the bursts of high amplitude spikes. Phenobarbital also delayed the start of seizures without changing the total duration of epileptic discharges. The markedly limited efficacy of the antiepileptic drugs studied in our neonatal stroke rat model is frequently observed in human neonatal seizures. Both drugs did not modify the stroke volume, which suggests that the modification of the quantity of bursts of high amplitude spikes does not influence the infarct size. In the absence of a reduction in seizure burden by the antiepileptic drugs, we increased the seizure burden and stroke volume by combining our neonatal stroke model with a lithium-pilocarpine-induced status epilepticus. Our data suggest that the reduction of burst of spikes did not influence the stroke volume. The presence of organized seizure with a pattern close to what is observed in human newborns seems related to the presence of the infarct. Further research is required to determine the relationship between seizure burden and infarct volume.

International audience; FSGS, the most common primary glomerular disorder causing ESRD, is a complex disease that is only partially understood. Progressive sclerosis is a hallmark of FSGS, and genetic tracing studies have shown that parietal epithelial cells participate in the formation of sclerotic lesions. The loss of podocytes triggers a focal activation of parietal epithelial cells, which subsequently form cellular adhesions with the capillary tuft. However, in the absence of intrinsic podocyte alterations, the origin of the pathogenic signal that triggers parietal epithelial cell recruitment remains elusive. In this study, investigation of the role of the endothelial PAS domain-containing protein 1 (EPAS1), a regulatory a subunit of the hypoxia-inducible factor complex, during angiotensin II–induced hypertensive nephrop-athy provided novel insights into FSGS pathogenesis in the absence of a primary podocyte abnormality. We infused angiotensin II into endothelial-selective Epas1 knockout mice and their littermate controls. Although the groups presented with identical high BP, endothelial-specific Epas1 gene deletion accentuated albuminuria with severe podocyte lesions and recruitment of pathogenic parietal glomerular epithelial cells. These lesions and dysfunction of the glomerular filtration barrier were associated with FSGS in endothelial Epas1-deficient mice only. These results indicate that endothelial EPAS1 has a global protective role during glomerular hypertensive injuries without influencing the hypertensive effect of angiotensin II. Furthermore, endothelial Epas1 gene deficiency promotes FSGS in this model of hypertension, providing proof of principle that endothelial-derived signaling can trigger FSGS. These findings illustrate the potential importance of the EPAS1 endothelial transcription factor in secondary FSGS.