tbuckley/cabot-search huggingface dataset:
Human induced pluripotent cardiomyocytes as a model for cardiomyopathy with a Myozap gene mutation
Authors: F Zakzook, R Maria Cherian, K Aalto-Setala
Journal: Cardiovascular Research (2024)

Abstract Funding Acknowledgements Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): 1- Central Department of Missions, Egyptian Ministry of Higher education and Scientific Research. 2- small fund from Tampere University. The contractility of the heart is based on cardiomyocytes (CM). These cardiomyocytes are connected through a complex network of proteins forming the intercalated disc (ID) which is crucial to ensure mechanical and electrochemical coupling. Dilated cardiomyopathy (DCM) is a disease of the myocardium that can lead to heart failure and life-threatening arrhythmias. Up to 30% of DCM cases are caused by mutations in genes encoding proteins of the sarcomere (the basic contractile unit) or desmosome (a cell-to-cell adhesion structure) and the structural cytoskeleton. Myozap (Myocardium-Enriched Zonula Occludens-1-Associated Protein) is a distinctive cardiac-enriched ID protein. It is crucial for biomechanical stress adaption in CMs due to its outstanding role in the Rho/SRF (Serum Response Factor) signalling pathway. In this study, we have identified two Finnish families with DCM and carrying a novel variant in myozap. Our aim is to characterize myozap gene mutation-both heterozygous and homozygous truncating variants-as well as its implication in DCM. We have established patient-specific human induced pluripotent stem-cell lines and derived cardiomyocyte (hiPSC-CM) to study the disease at the cellular level. Myozap expression, compared to the control cell line, was evaluated by immunohistochemistry. Electrophysiological methods, including microelectrode array (MEA) and patch clamping, were implemented to measure various parameters with emphasis on those ones related to cell-cell connection e.g., the conduction velocity. Moreover, metabolic stress indicators, including oxygen consumption rate (OCR), were estimated by Seahorse. Additionally, qPCR and ELISA were performed to measure the colocalised and closely related genes to ID and protein level of troponin, respectively. Immunohistochemistry revealed downregulation and absence of myozap expression in heterozygous and homozygous cell lines, respectively. Compared to the control one, differences in BPM, FPD were observed. Metabolic analysis of the myozap mutant elucidated mitochondrial impairment compared to the control. Some SRF and sarcomeric target genes, including MYH7, MYH6 and Myl-2 were downregulated. On the contrary, apoptotic genes (e.g., caspase 3) were upregulated. Tight junction protein (TJP) was upregulated, and this is very importance since it is closely related to the myozap in the ID proteins network. Moreover, troponin protein level, measured by ELISA, showed upregulation in mutant myozap. In conclusion, our study provides a new insight into understanding myozap’s significance in cardiac biology and in cardiomyopathy pathophysiology.
anti-interleukin-18 as therapy against atherosclerosis
Authors: E Van Ingen, A C Foks, M N A Bernabe Kleijn, J Kuiper, I Bot
Journal: Cardiovascular Research (2024)

Abstract Funding Acknowledgements Type of funding sources: Foundation. Main funding source(s): Established Investigator of the Dutch Heart Foundation Background Interleukin-18 (IL-18) is a pro-inflammatory cytokine and is secreted by macrophages after NLRP3-inflammasome activation. IL-18 is important for the induction of the Th1 response and overexpression of IL-18 aggravates atherosclerosis, suggesting that inhibition of IL-18 may act atheroprotective. In this study, we investigated the therapeutic potential of an IL-18 neutralizing antibody (anti-IL18) on atherosclerosis development. Methods and results Female ApoE-/- mice were fed a Western-type diet for 8 weeks and simultaneously received an antibody against IL-18 (100 µg/mouse; n=15) or a rat IgG2a control (100 µg/mouse; n=15) 3x per week intraperitoneally, after which the mice were sacrificed. First, we assessed macrophage phenotype in the peritoneal cavity. Expression of the proinflammatory markers CD80 (control: 46.3±1.4 *103; p&amp;lt;0.05 vs. anti-IL18: 40.4 ±1.7 *103) and iNOS (control: 15.5±1.8 *102 vs. anti-IL18: 8.0±1.9 *102; p&amp;lt;0.01) were reduced. In the aorta, MFIs of anti-inflammatory macrophage markers Arginase-1 (control: 389±99 vs. anti-IL18: 654±85; p=0.06) and CD206 (control: 55.2±2.4 *103 vs. anti-IL18: 62.8±3.7 *103; p=0.1) tended to be increased expression in the ascending aorta of anti-IL18 mice compared to controls. In addition, anti-IL18 treatment promoted the number of CD4 T cells (control: 20±1% vs. anti-IL18: 28±1%; p&amp;lt;0.0001) in the mediastinal lymph node and increased it’s regulatory phenotype (Tregs; Foxp3+) of CD4 (control: 23±1% vs. anti-IL18: 26±1%; p=0.07) and CD8 T cells (control: 0.4±0.02% vs. anti-IL18: 0.9±0.09%; p&amp;lt;0.0001). These effects however, did not translate into an effect on plaque size in the aortic root, as measured using an Oil-Red-O staining, which did not differ between the control and anti-IL18 treatment group (control: 47.1±2.4 *104 µm2 vs. anti-IL18: 43.4±2.3 *104 µm2). Conclusions Anti-IL18 treatment reduced the proinflammatory phenotype of peritoneal macrophages and promoted Tregs in the mediastinal lymph node. Further analyses on plaque stability and intraplaque macrophage subsets are currently being performed.
Asporin expression is associated with human atherosclerotic plaque integrity
Authors: P Fountas, C Gialeli, J Sun, M Nitulescu, A Persson, E Bengtsson, A Edsfeldt, I Goncalves
Journal: Cardiovascular Research (2024)

Abstract Funding Acknowledgements Type of funding sources: Other. Main funding source(s): This work was supported by the Swedish Research Council, the Swedish Heart and Lung Foundation, Skåne University Hospital funds Background Calcification serves as a clinical marker of atherosclerotic plaque burden. Recent studies have also shed light on its intricate association with plaque vulnerability, likely depend on calcification structures and the surrounding environment. Asporin (ASPN) is a member of the small-leucine-rich proteoglycans that contains a unique and well-conserved stretch of aspartate (D) residues, which mimic the role of glycosaminoglycans. Via its D-repeat, ASPN can interact with calcium and several other extracellular matrix molecules, thus influencing collagen mineralization and TGF-β signaling. ASPN expression has been shown to be higher in asymptomatic compared to symptomatic atherosclerotic plaques, suggesting a potential protective role. However, the role of ASPN in maintaining plaque integrity remains unknown. Purpose Here we aimed to explore the role of ASPN in atherosclerosis, by investigating if ASPN was expressed in human carotid plaques and by determining if ASPN is associated with risk for postoperative cardiovascular events and death. Methods ASPN and TGF-β protein levels were measured by ELISA and Milliplex in 176 human plaque tissue homogenates obtained from the Carotid Plaque Imaging Project (CPIP) biobank. Plaque tissue sections were stained for ASPN, destabilizing (CD68, oil red O, glycophorin A) and stabilizing plaque components (Movat, α-actin). Plaque tissue RNA expression levels were assessed in 82 plaques using bulk RNA sequencing. Plaque levels of phosphate, elastin and collagen were measured using ELISA. Results ASPN protein levels were higher in plaques from asymptomatic patients compared to symptomatic patients (p=0.011). ASPN RNA levels correlated positively to RNA levels of the smooth muscle cell markers ACTA2, MYH11 and TAGLN. Moreover, protein levels correlated with plaque levels of phosphate (r=0.258, p=0.001), elastin (r=0.423, p&amp;lt;0.001), collagen (r=0.248, p=0.002) and stability factors like the TGF-β family members, TGF-β1 (r=0.176, p=0.035), TGF-β2 (r=0.581, p&amp;lt;0.001) and TGF-β3 (r=0.396, p&amp;lt;0.001). Furthermore, plaque ASPN protein concentration, correlated inversely with a histological plaque vulnerability index (r=-0.265, p=0.0029), which is ratio between the plaque area of destabilizing (macrophages, lipids, intra-plaque hemorrhage) and stabilizing plaque components (collagen and smooth muscle cells). Additionally, above median ASPN levels were associated with lower risk for postoperative cardiovascular events (p=0.008) and death (p=0.009). Conclusion Our findings suggest that elevated levels of ASPN might have a crucial role in maintaining plaque stability, affecting plaque calcification.
Pirfenidone treatment reduces cardiac allograft vasculopathy in a mouse model
Authors: C Graebner, M Scheunchen, F Theil, A Kuckhahn, N Vogg, A Gessner, N Fritz, M Ramsperger-Gleixner, O Dewald, C Heim
Journal: Cardiovascular Research (2024)

Abstract Funding Acknowledgements Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): ISHLT research grant Objectives Chronic rejection in the form of cardiac allograft vasculopathy after heart transplantation remains without effective treatment. Main characteristics of cardiac allograft vasculopathy are immigration of leukocytes and proliferation of smooth muscle cells - collectively resulting in development of a neointima narrowing the vessel lumen and leading to graft ischemia. Pirfenidone is an anti-fibrotic drug with anti-inflammatory properties that is already approved for treatment of idiopathic pulmonary fibrosis. The aim of this study was to evaluate whether application of pirfenidone leads to reduced luminal occlusion corresponding with decreased chronic rejection in a mouse transplant model. Methods Murine thoracic aortas were transplanted into the abdominal aorta of CBA mice (H2k). For allogeneic transplantation, C57BL/6 mice (H2b) were used as donors (n = 8 / group). After transplantation, mice were fed a 0.5% pirfenidone diet versus conventional diet. Preliminary tests were performed determining the blood pirfenidone level by mass spectrometry throughout the study period on days 1, 3, 7, 14, 21 and 28, respectively, as well as after obtaining the aortic grafts on day 30 for histological analysis. Results Preliminary tests confirmed the successful uptake of pirfenidone by achieving constant plasma levels of pirfenidone and its metabolite 5-carboxy-pirfenidone over the whole examination period. Pirfenidone treated murine aortic grafts showed significantly reduced neointima formation compared to control allografts (luminal occlusion: 32.92 % ± 13.02 % vs. 42.44 % ± 19.81 %, p=0.046). As expected, syngeneic aortic grafts with and without pirfenidone treatment showed no luminal occlusion. Conclusion The results indicate that pirfenidone application after aortic transplantation reduces neointima formation and thus chronic rejection in a mouse aortic transplant model. Further analyses of underlying mechanisms are currently underway.
Increased bone morphogenetic protein 10 in precapillary pulmonary hypertension patients
Authors: A Llucia-Valldeperas, J Van Wezenbeek, J A Groeneveldt, R Smal, G Sanchez-Duffhues, C Becher, M L Handoko, L Meijboom, J T Marcus, P Symersky, H W M Niessen, A Vonk-Noordegraaf, H J Bogaard, M J Goumans, F S De Man
Journal: Cardiovascular Research (2024)

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Netherlands Organization for Scientific Research: NWO-VICI num. 918.16.610 and NWO-VIDI num. 917.18.338. Dutch Heart Foundation Dekker senior post-doc grant num. 2018T059 and the Netherlands CardioVascular Research Initiative: CVON-2017-10 DOLPHIN-GENESIS and CVON-2018-29 PHAEDRA-IMPACT. Fundació La Marató de TV3 num.202038. The Spanish Ministry of Science through the Ramón y Cajal grant num.RYC2021-030866-I. Introduction Precapillary pulmonary hypertension (PH) results in increased right atrial (RA) stretch and pressure. The right atrium is the major source of bone morphogenetic protein (BMP) 10 (BMP10) in adults, mostly produced by RA cardiomyocytes. The major predisposing risk factor for PH involves loss-of-function mutations in the bone morphogenetic protein receptor type 2 (BMPR2) gene, through which BMP10 and BMP9 transduce signals. Purpose The aim of this study was to investigate if BMP10 expression is altered in PH, and whether BMP10 signaling activity associates with right ventricular (RV) adaptation, RA function and disease progression. Methods We investigated BMP10 gene and protein expressions in RA tissue. We determined BMP10 and BMP9 plasma levels by ELISA. We studied BMP10 signaling activity in PH and CTEPH patients before and after pulmonary endarterectomy (PEA). Results BMP10 mRNA, protein and activity were significantly increased in the PH right atrium. While circulating levels of BMP10 and BMP9 proteins were increased, no significant changes were observed in BMP10 signaling activity between PH and controls. In a cohort of CTEPH patients, BMP10 signaling activity was reduced after PEA which coincided with improved hemodynamics and RV function. Interestingly, high BMP10 activity was associated with reduced RV function and adaptation, increased RA dilation and decreased RA function. No associations were observed with hemodynamics or general disease markers. Conclusions RA BMP10 expression and plasma levels are increased in precapillary PH. High BMP10 transcriptional activity was associated with worse RV function, RV adaptation, RA dilation and RA function. Future studies are needed to further understand the mechanism underlying BMP10 secretion and function in PH.
Estrogen and the estrogen receptor in ZSF1 rats with heart failure with preserved ejection fraction
Authors: P Buettner, S Werner, H Thiele
Journal: Cardiovascular Research (2024)

Abstract Funding Acknowledgements None. Background Heart failure with preserved ejection fraction (HFpEF) is more prevalent in women, so declining estrogen levels after menopause may be involved in genesis of the disease. Estrogen is cardio-protective, affecting blood pressure and vasodilatation and endothelial dysfunction is discussed as HFpEF pathomechanism. However, the potential connection between HFpEF and estrogen levels remains poorly understood. The well-established HFpEF ZSF1 rat model was used to analyze endothelial dysfunction, and a pronounced imbalance of the NO synthase substrates arginine and homoarginine was observed. Of note, estrogen levels in woman are directly and positively associated to homoarginine levels. Purpose We characterized serum estrogen levels and the expression of the estrogen receptor alpha (ERα) in the hearts of female ZSF1 HFpEF rats to investigate a possible contribution of estrogen signaling in HFpEF manifestation and to evaluate the suitability of this animal model in the context of estrogen and HFpEF. Methods In total, 12 obese ZSF1 rats with HFpEF (O-ZSF1) and 12 lean healthy ZSF1 rats (L-ZSF1) at 20 weeks of age and 5 animals of either phenotype aged 32 weeks were analyzed. Further, six O-ZSF1 rats were supplemented with homoarginine (hArg) when HFpEF was manifest and were observed up to 32 weeks of age. The manifestation of HFpEF was confirmed by echocardiography and determination of NT-proBNP by ELISA. Circulating estradiol (E2) in serum was determined using ELISA. Expression of the estrogen receptor alpha was determined by Western Blot analysis in the left ventricle (LV), septum and right ventricle (RV). Results Serum estradiol levels were similar in age-matched L-ZSF1 and O-ZSF1, but were ~2-fold increased at an age of 32 weeks compared to 20 weeks (p=0.002). The canonical ERα-66kDa was very weakly expressed in all tissues. ERα-45kDa expression in the LV was lower in O-ZSF1 at an age of 20 weeks (-46%, p=0.008) and at 32 weeks (-46%, p=0.002). ERα-45kDa expression in LV was 2-fold higher than in septum and 5-fold higher than in RV in rats aged 20 weeks (p&amp;lt;0.001). In RV, no differences in ERα-45kDa expression were observed. Supplementation of O-ZSF1 with hArg reestablished the ERα-45kDa expression in the LV (p=0.005 vs. O-ZSF1 without supplementation). Conclusion The manifestation and progression of HFpEF in ZSF1 rats is accompanied by a decrease of the ERα-45kDa expression in the LV, whereas the RV is not affected. Supplementation with homoarginine normalizes ERα-45kDa expression. The ERα-45kDa isoform was found to suppress the transcriptional activity of the classical ERα-66kDa isoform and to be an acute regulator of endothelial NO synthase in response to estrogen. These results suggest that altered ERα expression in the LV may represent a novel pathomechanism in HFpEF. In combination with decreasing estrogen levels in woman, adverse consequences for NO production in the LV seem likely.
Rapamycin reduces atherosclerotic plaque inflammation in aged mice
Authors: J De Mol, D H De Korte, V Smit, J Kuiper, A C Foks
Journal: Cardiovascular Research (2024)

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – EU funding. Main funding source(s): 1. ERA-CVD. Beat ATHERO consortium. 2. Dutch Heart Foundation Aims Aging is the most dominant risk factor of atherosclerotic cardiovascular disease (CVD), the main underlying cause of death worldwide. Both aging and atherosclerosis are associated with changes in the composition and function of the immune system, such as an enlarged T cell effector memory pool and elevated pro-inflammatory cytokine secretion. Since the accumulation of these pro-inflammatory factors contribute to atherosclerosis progression, halting inflammation might be a promising strategy to combat CVD. Rapamycin is an immunosuppressant that was recently discovered to increase lifespan due to the inhibition of senescent cells and effector T cells. We therefore hypothesized that rapamycin treatment can attenuate pro-atherogenic immunity in aged mice. Methods To explore the effects of rapamycin treatment, we administrated 1 mg/kg rapamycin or control solvent to aged (22 months old) male atherosclerotic Ldlr-/- mice (n=16 per group) three times a week intraperitoneally. After eight weeks, mice were sacrificed and their organs were collected for flow cytometry, single-cell RNA sequencing and histological analysis. Results Using flow cytometry, we revealed that rapamycin treatment decreased total T cell numbers in the atherosclerotic aorta and spleen compared to control treatment and attributed to a 24% increase in the relative frequency of immunosuppressive regulatory T cells in the aorta (rapa: 70.6±3.0% vs. ctrl: 57.1±3.8%, p&amp;lt;0.05), indicating skewing towards anti-atherogenic immunity. Within the reduced effector T cell pool of rapamycin-treated mice, we observed increased percentages of IL-10 and IFN-γ-expressing CD4+ and CD8+ T cells. In addition, rapamycin diminished the percentage of pro-atherogenic age-associated B cells (rapa: 7.5±1.8% vs. ctrl: 9.2±1.5%, p&amp;lt;0.05) in the mediastinal lymph nodes, and the percentage of pro-atherogenic age-associated B cells in the mediastinal lymph nodes, and reduced the expression of the senescent markers p19 and BTG2 in the spleen. In line with attenuated inflammation we observed a 36% reduction in relative plaque macrophage content in rapamycin-treated mice (rapa: 14.0±3.6% vs. ctrl: 21.8±5.5%, p&amp;lt;0.05). Conclusions Collectively, our study demonstrates that rapamycin treatment in aged atherosclerotic mice promotes regulatory T cells and reduces systemic and plaque accumulation of T cells, ABCs and macrophages. This provides a new understanding of rapamycin in regulating age-associated atherogenic immunity, indicating rapamycin could be a potential therapeutic to halt CVD.
Transcriptional regulation of macrophage inflammation in the heart failure with preserved ejection fraction
Authors: E Gorica, S A Mohammed, A Mengozzi, A Mongelli, M Telesca, F A Wenzl, F Ruschitzka, N Hamdani, S Costantino, F Paneni
Journal: Cardiovascular Research (2024)

Abstract Funding Acknowledgements None. Introduction Heart failure with preserved ejection fraction (HFpEF) is a global public health problem with no effective treatment available. Pro-inflammatory cardiac macrophages are emerging as key determinants of adverse left ventricular remodeling; however, their role in HFpEF remains poorly understood. Mechanistically, the recruitment and activation of macrophages represent a key event in maladaptive myocardial remodeling in HFpEF patients. Evidence suggests that remodeling processes in HFpEF hearts are orchestrated and amplified by cardiac macrophages which regulate cardiomyocyte function, endothelial cell activation and fibroblast differentiation. Here we sought to determine the role of macrophage inflammation in experimental and human HFpEF. Methods Experiments were performed in rat cardiomyocytes (H9c2), human endothelial cells (HAECS), transgenic mice, and left ventricular (LV) myocardial samples from patients with HFpEF. H9c2 and HAECS treated with pro-inflammatory macrophage-like cells (RAW 264.7) conditional media in the presence or knockdown of a top-ranking activator of M1 type macrophages such as nuclear receptor corepressor 1 (NCOR1), were used to elucidate better the involvement of this gene in transcriptional regulation in vitro. The cardiac function of myeloid cell-specific NCOR1 knockout HFpEF mice undergoing a high-fat diet and L-NAME was investigated. LV myocardial samples were used to evaluate the pro-inflammatory activity of macrophages in human HFpEF tissues. Results Human and murine LV specimens showed upregulation of vascular adhesion molecules (ICAM1, ICAM2, E-selectin), recruitment of M1 macrophages to the myocardium, and decreased M2 macrophages. Notably, NCOR1 deletion in macrophages protected against diastolic dysfunction, exercise intolerance, and myocardial inflammation (TNF-a, IL6, IL-1b). Mechanistically, induction of metabolic stress by palmitic acid induced macrophage polarization, upregulation of NCOR1 and inflammatory genes in RAW cells. By contrast, Finally, NCOR1 depletion prevented pro-inflammatory transcriptional programs and secretion of TNF-a, IL6 and IL-1b in the macrophage secretome. Conclusion Targeting macrophage NCOR1 could represent a promising approach to blunt myocardial inflammation in HFpEF.