Gene transfer of wild-type apoA-I and apoA-I Milano reduce atherosclerosis to a similar extent

<p>Abstract</p> <p>Background</p> <p>The atheroprotective effects of systemic delivery of either apolipoprotein A-I (wtApoA-I) or the naturally occurring mutant ApoA-I Milano (ApoA-I_M) have been established in animal and human trials, but direct comparison studies evaluating the phenotype of ApoA-I or ApoAI-Milano knock-in mice or bone marrow transplantated animals with selectively ApoA-I or ApoAI-Milano transduced macrophages give conflicting results regarding the superior performance of either one. We therefore sought to compare the two forms of apoA-I using liver-directed somatic gene transfer in hypercholesterinemic mice – a model which is most adequately mimicking the clinical setting.</p> <p>Methods and results</p> <p>Vectors based on AAV serotype 8 (AAV2.8) encoding wtApoA-I, ApoA-I_Mor green fluorescent protein (GFP) as control were constructed. LDL receptor deficient mice were fed a Western Diet. After 8 weeks the AAV vectors were injected, and 6 weeks later atherosclerotic lesion size was determined by aortic <it>en face </it>analysis. Expression of wtApoA-I reduced progression of atherosclerosis by 32% compared with control (p = 0.02) and of ApoA-I_Mby 24% (p = 0.04). There was no significant difference between the two forms of ApoA-I in inhibiting atherosclerosis progression.</p> <p>Conclusion</p> <p>Liver-directed AAV2.8-mediated gene transfer of wtApoA-I and ApoA-I_Meach significantly reduced atherosclerosis progression to a similar extent.</p

Interleukin-6 predicts inflammation-induced increase of Glucagon-like peptide-1 in humans in response to cardiac surgery with association to parameters of glucose metabolism

Objective: Glucagon-like peptide-1 (GLP-1) is an incretin hormone, which gets secreted in response to nutritional stimuli from the gut mediating glucose-dependent insulin secretion. Interestingly, GLP-1 was recently found to be also increased in response to inflammatory stimuli in an interleukin 6 (IL-6) dependent manner in mice. The relevance of this finding to humans is unknown but has been suggested by the presence of high circulating GLP-1 levels in critically ill patients that correlated with markers of inflammation. This study was performed to elucidate, whether a direct link exists between inflammation and GLP-1 secretion in humans. Research design and methods: We enrolled 22 non-diabetic patients scheduled for cardiac surgery as a reproducible inflammatory stimulus with repeated blood sampling before and after surgery. Results: Mean total circulating GLP-1 levels significantly increased in response to surgery from 25.5 +/- 15.6 pM to 51.9 +/- 42.7 pM which was not found in a control population. This was preceded by an early rise of IL6, which was significantly associated with GLP-1 under inflammatory but not basal conditions. Using repeated measure ANCOVA, IL6 best predicted the observed kinetics of GLP-1, followed by blood glucose concentrations and cortisol plasma levels. Furthermore, GLP-1 plasma concentrations significantly predicted endogenous insulin production as assessed by C-peptide concentrations over time, while an inverse association was found for insulin infusion rate. Conclusion: We found GLP-1 secretion to be increased in response to inflammatory stimuli in humans, which was associated to parameters of glucose metabolism and best predicted by IL6

Increased plasma zonulin in patients with sepsis

Introduction: Zonulin is a eukaryotic protein structurally similar to Vibrio cholerae’s zonula occludens toxin. It plays an important role in the opening of small intestine tight junctions. The loss of gut wall integrity during sepsis might be pivotal and has been described in various experimental as well as human studies. Increased levels of zonulin could be demonstrated in diseases associated with increased intestinal inflammation, such as celiac disease and type 1 diabetes. We therefore investigated the role of plasma levels of zonulin in patients with sepsis as a non-invasive marker of gut wall integrity. Materials and methods: Plasma level of zonulin was measured in 25 patients with sepsis, severe sepsis or septic shock according to ACCP/SCCM criteria at the first day of diagnosed sepsis. 18 non-septic post-surgical ICU-patients and 20 healthy volunteers served as control. Plasma levels were determined by using commercially available ELISA kit. Data are given as median and interquartile range (IQR). Results: Significantly higher plasma concentration of zonulin were found in the sepsis group: 6.61 ng/mL (IQR 3.51-9.46), as compared to the to the post-surgical control group: 3.40 ng/mL (IQR 2.14-5.70) (P = 0.025), as well as to the healthy group: 3.55 ng/mL (IQR 3.14-4.14) (P = 0.008). Conclusion: We were able demonstrate elevated levels of plasma zonulin, a potential marker of intestinal permeability in septic patients. Increased zonulin may serve as an additional mechanism for the observed increased intestinal permeability during sepsis and SIRS

Low Adiponectin Levels Are an Independent Predictor of Mixed and Non-Calcified Coronary Atherosclerotic Plaques

Atherosclerosis is the primary cause of coronary artery disease (CAD). There is increasing recognition that lesion composition rather than size determines the acute complications of atherosclerotic disease. Low serum adiponectin levels were reported to be associated with coronary artery disease and future incidence of acute coronary syndrome (ACS). The impact of adiponectin on lesion composition still remains to be determined. We measured serum adiponectin levels in 303 patients with stable typical or atypical chest pain, who underwent dual-source multi-slice CT-angiography to exclude coronary artery stenosis. Atherosclerotic plaques were classified as calcified, mixed or non-calcified. In bivariate analysis adiponectin levels were inversely correlated with total coronary plaque burden (r = -0.21, p = 0.0004), mixed (r = -0.20, p = 0.0007) and non-calcified plaques (r = -0.18, p = 0.003). No correlation was seen with calcified plaques (r = -0.05, p = 0.39). In a fully adjusted multivariate model adiponectin levels remained predictive of total plaque burden (estimate: -0.036, 95%CI: -0.052 to -0.020, p<0.0001), mixed (estimate: -0.087, 95%CI: -0.132 to -0.042, p = 0.0001) and non-calcified plaques (estimate: -0.076, 95%CI: -0.115 to -0.038, p = 0.0001). Adiponectin levels were not associated with calcified plaques (estimate: -0.021, 95% CI: -0.043 to -0.001, p = 0.06). Since the majority of coronary plaques was calcified, adiponectin levels account for only 3% of the variability in total plaque number. In contrast, adiponectin accounts for approximately 20% of the variability in mixed and non-calcified plaque burden. Adiponectin levels predict mixed and non-calcified coronary atherosclerotic plaque burden. Low adiponectin levels may contribute to coronary plaque vulnerability and may thus play a role in the pathophysiology of ACS

Endothelial ADAM10 controls cellular response to oxLDL and its deficiency exacerbates atherosclerosis with intraplaque hemorrhage and neovascularization in mice

IntroductionThe transmembrane protease A Disintegrin And Metalloproteinase 10 (ADAM10) displays a “pattern regulatory function,” by cleaving a range of membrane-bound proteins. In endothelium, it regulates barrier function, leukocyte recruitment and angiogenesis. Previously, we showed that ADAM10 is expressed in human atherosclerotic plaques and associated with neovascularization. In this study, we aimed to determine the causal relevance of endothelial ADAM10 in murine atherosclerosis development in vivo.Methods and resultsEndothelial Adam10 deficiency (Adam10ecko) in Western-type diet (WTD) fed mice rendered atherogenic by adeno-associated virus-mediated PCSK9 overexpression showed markedly increased atherosclerotic lesion formation. Additionally, Adam10 deficiency was associated with an increased necrotic core and concomitant reduction in plaque macrophage content. Strikingly, while intraplaque hemorrhage and neovascularization are rarely observed in aortic roots of atherosclerotic mice after 12 weeks of WTD feeding, a majority of plaques in both brachiocephalic artery and aortic root of Adam10ecko mice contained these features, suggestive of major plaque destabilization. In vitro, ADAM10 knockdown in human coronary artery endothelial cells (HCAECs) blunted the shedding of lectin-like oxidized LDL (oxLDL) receptor-1 (LOX-1) and increased endothelial inflammatory responses to oxLDL as witnessed by upregulated ICAM-1, VCAM-1, CCL5, and CXCL1 expression (which was diminished when LOX-1 was silenced) as well as activation of pro-inflammatory signaling pathways. LOX-1 shedding appeared also reduced in vivo, as soluble LOX-1 levels in plasma of Adam10ecko mice was significantly reduced compared to wildtypes.DiscussionCollectively, these results demonstrate that endothelial ADAM10 is atheroprotective, most likely by limiting oxLDL-induced inflammation besides its known role in pathological neovascularization. Our findings create novel opportunities to develop therapeutics targeting atherosclerotic plaque progression and stability, but at the same time warrant caution when considering to use ADAM10 inhibitors for therapy in other diseases

Rare Case of an Adult With Double-Chambered Left VentricleNovel Teaching Points

The rare case of an adult with a double-chambered left ventricle was revealed using multimodality imaging using echocardiography and cardiac magnetic resonance imaging in a 38-year-old asymptomatic male patient. The congenital malformation was dominated by a second, coarsely trabeculated muscular shelf dividing the left ventricle into 2 chambers without signs for left ventricular inflow or outflow tract obstruction. The partition wall did not show any signs for intramyocardial fibrosis in late gadolinium enhancement cardiovascular magnetic resonance imaging. Flow measurements excluded a relevant intracardial shunt across the additive perimembranous ventricular septal defect. There were no signs for global right and left ventricular dysfunction with left and right ventricular volumes and ejection fraction within normal limits. A conservative approach was recommended. In summary, we are able to present the case of an adult with a double-chambered left ventricle with a second muscular “septum” partially dividing the left ventricular cavity without causing a relevant impact on cardiac function or clinical signs for heart failure. Résumé: Le cas rare d’un adulte présentant un ventricule gauche à double chambre a été révélé par une imagerie multimodale utilisant l’échocardiographie et l’imagerie par résonnance magnétique cardiaque chez un homme asymptomatique de 38 ans. La malformation congénitale était dominée par une deuxième bande musculaire grossièrement trabéculaire divisant le ventricule gauche en deux chambres sans signes d’obstruction des chambres d’admission et d’éjection du ventricule gauche. La cloison de partition ne montrait aucun signe de fibrose intramyocardique à l’imagerie par résonnance magnétique cardiovasculaire avec rehaussement tardif au gadolinium. Les mesures du débit ont exclu un shunt intracardiaque significatif à travers le défaut septal ventriculaire transmembranaire supplémentaire. Il n’y avait pas de signe de dysfonction ventriculaire droite et gauche globale, les volumes ventriculaires gauche et droit et la fraction d’éjection étant dans les limites normales. Une approche conservatrice a été recommandée. En résumé, nous pouvons présenter le cas d’un adulte porteur d’un ventricule à double chambre avec une deuxième « cloison » musculaire divisant partiellement la cavité ventriculaire gauche sans causer d’effet notable sur la fonction cardiaque ou de signes cliniques d’insuffisance cardiaque