tbuckley/cabot-search huggingface dataset:
LMNA p.Arg624His missense variant reduces lamin expression at mRNA level: elucidating molecular pathways toward cardiac involvement in laminopathies
Authors: E Lozano-Velasco, C J Morales-Alcazar, A M Martinez-Rodriguez, S Cano-Carrillo, A B Garcia-Ruano, J A Urbano-Moral, D Franco
Journal: Cardiovascular Research (2024)

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Ministry of Science and Innovation LMNA is a gene encoding lamin A/C proteins of the cell nuclear lamina. Pathogenic variants in LMNA cause a group of diseases known as laminopathies, a common cause of dilated cardiomyopathy (DCM). LMNA is the second most frequently mutated gene in DCM. Although molecular mechanisms underlying the cardiac involvement are unclear, previous studies have shown a reduction of the lamin expression in LMNA heterozygous mutation carriers. We identified a missense variant in LMNA, c.1871G&amp;gt;A (p.Arg624His), in a family affected with DCM. In this study, we analysed the impact of the p.Arg624His variant on the mRNA expression through quantitative PCR (qPCR) to demonstrate its pathogenicity. RNA was isolated from patient’s peripheral blood lymphocytes. Quantitative reverse transcription PCR (RT-qPCR) with LMNA specific primers was performed to measure lamin RNA levels. Whole-exome sequencing (WES) through next-generation sequencing (NGS) yielded an heterozygous missense variant in the LMNA gene (NM_170707.4(LMNA): c.1871G&amp;gt;A; p.Arg624His; ClinVar ID 66870) classified as variant of uncertain significance (VUS) in five members of a family affected with DCM. Computational (In-Silico) programs predict a damaging effect and variant is absent from controls in population databases. RT-qPCR demonstrated a significant reduction in the LMNA mRNA expression between the control (II.1) and affected family members (II.3, III.1) (Figure 2). According to evidence of co-segregation, variant frequency, results of in-silico predictors and mRNA reduction, LMNA p.Arg624His variant has been reclassified as pathogenic. In this study we reclassified to pathogenic a variant of uncertain significance in LMNA which reduces mRNA expression and leads to cardiac laminopathy. Further investigations are needed to determine the effect on the protein.
The RGK protein rrad regulates cardiac calcium levels in zebrafish
Authors: J Salgado-Almario, A Martinez-Sielva, P Mercedes, M Vicente, B Domingo, J Llopis
Journal: Cardiovascular Research (2024)

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Ministry of Science, Innovation and Universities, Spain Background/Introduction High voltage-activated Ca2+ (CaV) channels are essential for excitation-contraction coupling. RGK proteins (Gem, Rad, Rem, and Rem2) are small Ras-like G proteins that bind CaV β-subunits and profoundly inhibit CaV1/CaV2 channels. A recent study showed that Rad inhibits CaV1.2 channels in cardiomyocytes, thus mediating the enhanced inotropy and chronotropy by β-adrenergic agonists during the fight-or-flight response. The zebrafish has emerged as a useful in vivo animal model in cardiovascular physiology and pathophysiology. The role of zebrafish rrad, the orthologe of the human RAD, in the regulation of cardiac Ca2+ homeostasis in zebrafish has not been investigated. Purpose The aim of this study was to investigate the role of rrad in cardiac Ca2+ regulation in zebrafish. Methods We evaluated the cardiac Ca2+ dynamics, heart rhythm, and hemodynamics in transgenic zebrafish larvae that overexpress rrad in the heart, as well as in heterozygous rrad knockout larvae. Measurements were done in the beating heart of 3 dpf transgenic zebrafish larvae expressing the fluorescent Ca2+ biosensor Twitch-4. Results In some larvae, overexpression of rrad induced a severe enlargement of the atrium with pericardial edema and a high mortality rate. In addition, the ventricle displayed low Ca2+ levels and reduced contractility. The remaining larvae had no altered morphology, but the ventricular Ca2+ levels were reduced. On the other hand, preliminary results showed that down regulation of rrad in zebrafish larvae increased atrial and ventricular Ca2+ levels, like what was found in Rad knockout mice. Conclusion Taken together, these findings suggest that rrad in the zebrafish heart, as in mammals, is an inhibitor of the Ca2+ entry, presumably through CaV1/CaV2 channels, and demonstrate the zebrafish's utility as a model to study the involvement of rrad in cardiac function.
Targeting the histone methyltransferase SETD7 rescues diabetes-induced impairment of angiogenic response by transcriptional repression of semaphorin 3G
Authors: S A Mohammed, E Hoxha, M Albiero, G Karsai, S Masi, A Mengozzi, G Spinetti, F Ruschitzka, G P Fadini, S Costantino, F Paneni
Journal: Cardiovascular Research (2024)

Abstract Funding Acknowledgements Type of funding sources: Public Institution(s). Main funding source(s): Swiss National Science Foundation (n. 310030_197557), the Swiss Heart Foundation (n. FF19045) Background Peripheral artery disease (PAD) is highly prevalent in patients with diabetes (DM) and associates with a poor prognosis (1). Revascularization strategies failed to improve outcome, highlighting the need to develop new strategies to promote blood vessel growth (2). Histone modifications have emerged as key modulators of gene expression (3), however their role in angiogenic response in DM remains poorly understood. The present study investigates the role of chromatin remodelling in DM-related impairment of angiogenic response. Methodology Primary human aortic endothelial cells (HAECs) were exposed to normal glucose (NG, 5 mM) or high glucose (HG, 25 mM) levels for 48 hours. Unbiased gene expression profiling was performed by RNA sequencing (RNA-seq). Cell migration and tube formation were employed to study angiogenic properties in HAECs. Levels of the histone methyltransferase SETD7 and its chromatin signature at histone 3 on lysine 4 (H3K4me1) were investigated by Western blot and chromatin immunoprecipitation (ChIP). Pharmacological blockade of SETD7 was achieved by using the selective inhibitor (R)-PFI-2 while the inactive enantiomer (S)-PFI-2 was used as a control. Mice with streptozotocin-induced DM were orally treated with (R)-PFI-2 or vehicle and underwent hindlimb ischemia by femoral artery ligation. Blood flow was analysed at 24 hours, 7 and 14 days by laser Doppler imaging. Our experimental findings were also translated in endothelial cells (ECs) and gastrocnemius muscle samples obtained from DM patients with PAD. Results RNA-seq in HG-treated HAECs unveiled the histone methyltransferase SETD7 as the top-ranking transcript. SETD7 upregulation was associated with increased H3K4me1 levels as well as with impaired HAECs migration and tube formation. Both SETD7 silencing and inhibition by (R)PFI-2 rescued hyperglycemia-induced impairment of HAECs migration and tube formation, while SETD7 overexpression blunted the angiogenic response. RNA-seq and ChIP assays showed that SETD7-induced H3K4me1 enables the transcription of the angiogenesis inhibitor semaphorin-3G (SEMA-3G) by increasing chromatin accessibility to PPARγ. Moreover, SEMA-3G overexpression mimicked the impairment of angiogenic response observed during hyperglycemia. In DM mice with hindlimb ischemia, (R)-PFI-2 improved limb perfusion by suppressing SEMA-3G. Finally, RNAseq in vascular specimens from DM patients with PAD confirmed the upregulation of SETD7/SEMA3G signalling, whereas SETD inhibition restored angiogenic properties in ECs from DM patients. Conclusion SETD7 is a novel epigenetic target to boost neovascularization in DM patients with PAD.
The role of serotonin receptor 7 signalling in macrophages for the inflammatory response after myocardial infarction
Authors: F S Bahr, F E Mueller, N Weber, W Aguapong, S Neumueller, N Benen, M Ricke-Hoch, E Ponimaskin
Journal: Cardiovascular Research (2024)

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Deutsche Forschungsgemeinschaft (DFG) Background The hormone and neurotransmitter serotonin regulates multiple processes, including immune responses and inflammatory signalling. After a cardiac injury, such as myocardial infarction (MI), a precise regulation of the local inflammation is determining the healing process and therefore functional outcome. Immune cells invading the infarcted tissue can be critical modulators, and various immune cells, including macrophages, express different serotonin receptors. Purpose We characterized the importance of serotonin receptor 7 (5-HT7R) signalling in the regulation of macrophage function, which infiltrate the heart after MI and thus can determine the course of cardiac remodelling processes. Methods For investigation of 5-HT7R signalling on a cellular level, we used two in vitro models: primary murine bone marrow-derived macrophages (BMDM) and secondary human THP-1-derived macrophages. To validate the impact of macrophages on intact cardiac tissue, we pre-treated pro-inflammatory M1-like BMDMs with a selective 5-HT7R agonist and then co-cultured them with living cardiac rat slices for up to 48 h (ex vivo) followed by functional analysis. Results We detected 5-HT7R expression in both models during all stages of macrophage polarization at mRNA as well as protein levels. Pro-inflammatory THP-1-derived macrophages displayed significantly enhanced mRNA expression levels of IL-1β and CD80, while pro-inflammatory differentiated M1-like BMDMs showed increased levels of CD38 and TNFα. Pharmacological activation of 5-HT7R with LP-211 reduced phagocytic activity up to 4-fold in THP-1-derived pro-inflammatory macrophages, altered their cytokine secretion profile and inhibited their migration ability (recovered area in scratch assay 1.3 % after LP-211 treatment compared to 6.1 % in control). A reduction in phagocytic activity was also verified in pro-inflammatory BMDMs. Our results also indicate reduced ability of LP-211 treated M1-like BMDMs to infiltrate living cardiac slices 3, 12, 24 and 48 h after seeding. Conclusion 5-HT7R signalling affects the functional properties of pro-inflammatory macrophages, including phagocytic activity, motility and secretion profile. Targeted manipulation of 5-HT7R activity in macrophages represents thus a possibility to modulate their inflammatory profile, which might be a reasonable approach to guide recovery post MI.
BMP9 attenuates IL-33 signaling and prevents endothelial-to-mesenchymal transition in pulmonary arterial hypertension
Authors: C Becher, G Sanchez-Duffhues, M J Goumans
Journal: Cardiovascular Research (2024)

Abstract Funding Acknowledgements Type of funding sources: Foundation. Main funding source(s): Dutch Cardiovascular Alliance - PHAEDRA IMPACT Background Pulmonary Arterial hypertension (PAH) is a rare and progressive disease characterized by increased vascular resistance and remodeling of the pulmonary arteries. Disturbed Transforming growth factor (TGF)-β signaling, often associated with mutations in the gene encoding for the bone morphogenic protein receptor type II (BMPR2) and endothelial-to-mesenchymal transition (EndMT), emerges as a central culprit in the pathogenesis of PAH. Interleukin-33 (IL-33) has been identified as an inducer of EndMT, and its soluble receptor ST2 (sST2) has emerged as a potential biomarker for PAH. Bone morphogenic protein (BMP) 9, a BMPR2 ligand, showing a high affinity for endothelial cells, is being explored as a therapeutic approach. Purpose We hypothesize that a crosstalk between the TGF-β pathway and IL-33, a known promoter of vascular remodeling, occurs in PAH. This study aims to unravel the protective role of BMP9 in PAH, with a specific focus on the involvement of EndMT, a key player in the pathogenesis of vascular diseases. Methods The expression of IL-33 protein levels was assessed in Pulmonary Arterial Endothelial Cells (PAEC) and in lung tissues from experimentally induced PH (Sugen/Hypoxia (SuHx)) or control mice. Signal transduction and EndMT were investigated in PAECs exposed to IL-33, BMP9 and sST2, by gene expression analysis (qPCR), western blotting, ELISA and immunostaining. BMP9 and sST2 levels were measured in plasma from PAH patients by ELISA. Results Elevated IL-33 expression was observed in PAEC from PAH patients and lung tissues from SuHx mice compared to healthy controls. In vitro, BMP9 significantly induced the expression of the IL-33 soluble receptor ST2, while concurrently reducing IL-33 target gene expression. IL-33-induced EndoMT in PAEC was effectively mitigated by pre-incubation with BMP9, proving more efficacious than ST2 neutralizing antibody. Furthermore, a correlation between BMP9 and sST2 levels in plasma from PAH patients was identified. Conclusion Our findings demonstrate that BMP9 offers superior protections against IL-33-induced EndMT in PAECs compared to a ST2 neutralizing antibody. BMP9 induces expression of sST2, leading to IL-33 neutralization and subsequent EndMT inhibition. Therefore, targeting the IL-33 pathway in PAH patients presents a promising therapeutic option for preventing EndMT. This study provides novel insights into the pathogenesis of PAH, revealing a potential therapeutic target for this rare disease.BMP9 inhibits IL-33 downstream signalingBMP9 protects from IL-33-induced EndMT
Effect of diabetes on hypoxic microvascular remodeling and muscle damage in chronic limb threatening ischemia
Authors: G Juusola, G Wirth, T Ord, M Kaikkonen-Maatta, H Hakovirta, S Yla-Herttuala, P Korpisalo
Journal: Cardiovascular Research (2024)

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Finnish Academy/Research Council of Finland. The Finnish Foundation for Cardiovascular Research Background Hypoxia-induced arterialization of skeletal muscle capillaries has recently been identified as an important pathological feature that aggravates ischemic damage in chronic limb threatening ischemia (CLTI). Diabetes is also known to worsen the outcome of CLTI patients but its contribution to capillary arterialization and skeletal muscle pathology under ischemia is still largely unknown. Purpose To study how diabetes affects capillary arterialization and skeletal muscle pathology in CLTI. Methods Amputation muscle samples from CLTI patients (n=21 patients x3 samples) were histologically analyzed, grouped according to microvascular changes and RNA sequencing was performed. Differentially expressed genes, differentially regulated signaling pathways and histology between diabetics and non-diabetics were studied among corresponding microvascular groups. Also, spatial transcriptomics (n=2 patients) was applied to understand the mechanisms through which diabetes alters differential capillary responses on the tissue level. Results Diabetes differentially regulated gene expression of different angiogenic and arteriogenic factors including HIF1A, VEGFA, FLT1, NOTCH1, NOTCH3, NOS1 and ITGB3 in the CLTI muscles. This differential transcriptomic regulation translated as increased sprouting on the level of muscle capillaries, and also affected myofiber pathology. Muscle samples in diabetic patients often presented myofiber swelling and cell death that were uncommon in samples of non-diabetic patients. Conclusion Diabetic patients on the level of muscle transcriptional regulation show changes that can explain observed differential microvascular remodeling and worsened myofiber pathology. These results broaden our understanding of the causes for the exceptionally bad outcome of diabetics among CLTI patients.
Are telocytes related to maintenance of vascular homeostasis in normal and pathological aorta?
Authors: L Borges, R S P Falcao, S R Taboga, P S Gutierrez, J B Michel
Journal: Cardiovascular Research (2024)

Abstract Funding Acknowledgements None. The telocyte (TC) is a new interstitial cell type described in a wide variety of organs and loose connective tissues around small vessels, but its presence in large arteries remains unexplored. TCs have small cell bodies and remarkably thin, long, moniliform processes called telopods (Tps). Using transmission electron microscopy and immunofluorescence, we identified TCs in normal human thoracic aortas and in those with aneurysm and acute dissection (TAAD). In normal aortas the TCs were distributed throughout the connective tissue of the adventitial layer, in its innermost portion and at the zone of transition with the medial layer, with their long axes oriented parallel to the external elastic lamellae, forming a three-dimensional network, without prevalence in the media layer. In contrast, TAAD TCs were present in the medial layer and in regions of neovascularization. The most important feature of the adventitia of diseased aortas was the presence of numerous contacts between TCs and stem cells, including vascular progenitor cells. Although the biologically functional correlations need to be elucidated, the morphological observations presented here provide strong evidence of the involvement of TCs in maintaining vascular homeostasis in pathological situations of tissue injury.
HiPSC-derived cardiomyocyte cultivation and measurement of electrophysiological properties on gelatine/glucose/polypyrrole scaffold
Authors: R Vaiciuleviciute, A Alaburda, A Shelest, K Elkhoury, A Maziz, C Bergaud, M Schubert, K Guan, I Uzieliene, E Bernotiene
Journal: Cardiovascular Research (2024)

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – EU funding. Main funding source(s): EU Horizon 2020 Framework Programme (H2020) under Grant agreements No. 953138 (EMAPS-Cardio) Purpose Cardiotoxicity is one of the main side effects limiting development of new medicines and resulting in withdrawal of drugs from the market. There are different mechanisms of drug-induced cardiotoxicity, including arrhythmia, disruption of mitochondria function, apoptosis, altered growth factor signalling [1]. Heart on a chip model for drug testing seems attractive approach to evaluate the possible cardiotoxic effects on cell biological, but mostly electrophysiological properties. Our aim was to create a 3D system with a biocompatible scaffold, coated with a conductive layer, suitable for culturing and maturation of human induced pluripotent stem cell derived cardiomyocytes (hiPSC-CMs) and compatible with electrophysiology parameter measurement techniques. Methods Elastic scaffold was fabricated by electrospinning of gelatin-glucose microfibers followed by the vapor-phase and electrochemical deposition of conductive polymer polypyrrole (PPy) to create electroconductive layer. hiPSC-CMs at different maturation levels (at 6 vs 14 weeks) were used to test biocompatibility of the scaffold. To increase cell attachment, scaffold was treated with 0.1 M HCl and coated with Geltrex. Cells were stained with fluorescent dyes (Calcein AM, DAPI). Electrophysiological properties were analysed using intracellular calcium imaging (Cal520) and action potential recordings with sharp electrodes. HiPSC-CMs on coverslips were used as a 2D control. Results Calcein AM staining showed that high number of hiPSC-CMs attached to gelatine/glucose/PPy scaffold proving that the scaffold is biocompatible and cells remain viable even after long term incubation (&amp;gt; 2 weeks). HiPSC-CMs at lower maturity (6 weeks) had better attachment properties to it, indicating that more mature cardiomyocytes (14 weeks) gradually lose their capacity to attach to PPy surface. Intracellular calcium imaging showed that both types of cells generated synchronous spontaneous calcium oscillations on gelatine/glucose/PPy scaffolds. Action potential recordings in 3D were similar to those in 2D, and confirmed differences in hiPSC-CMs maturation levels – at lower maturation level hiPSC-CMs had lower upstroke velocity as compared to more matured hiPSC-CMs. Conclusions Gelatine/glucose/PPy scaffold is biocompatible for hiPSC-CMs cultivation, and suitable for evaluation of cardiomyocyte electrophysiological properties. Such electromechanoactive scaffold can be further employed for development of heart-on-a-chip model.
Engineered SPIONs functionalized with endothelin a receptor antagonist ameliorate liver fibrosis by inhibiting hepatic stellate cell activation
Authors: Marit ten Hove, Andreas Smyris, Richell Booijink, Lydia Wachsmuth, Uwe Hansen, Lejla Alic, Cornelius Faber, Carsten Hӧltke, Ruchi Bansal
Journal: Bioactive Materials (2024)

Endothelin-1/endothelin A receptor (ET-1/ETAR) pathway plays an important role in the progression of liver fibrosis by activating hepatic stellate cells (HSCs) - a key cell type involved in the pathogenesis of liver fibrosis. Inactivating HSCs by blocking the ET-1/ETAR pathway using a selective ETAR antagonist (ERA) represents a promising therapeutic approach for liver fibrosis. Unfortunately, small-molecule ERAs possess limited clinical potential due to poor bioavailability, short half-life, and rapid renal clearance. To improve the clinical applicability, we conjugated ERA to superparamagnetic iron-oxide nanoparticles (SPIONs) and investigated the therapeutic efficacy of ERA and ERA-SPIONs in vitro and in vivo and analyzed liver uptake by in vivo and ex vivo magnetic resonance imaging (MRI), HSCs-specific localization, and ET-1/ETAR-pathway antagonism in vivo. In murine and human liver fibrosis/cirrhosis, we observed overexpression of ET-1 and ETAR that correlated with HSC activation, and HSC-specific localization of ETAR. ERA and successfully synthesized ERA-SPIONs demonstrated significant attenuation in TGFβ-induced HSC activation, ECM production, migration, and contractility. In an acute CCl4-induced liver fibrosis mouse model, ERA-SPIONs exhibited higher liver uptake, HSC-specific localization, and ET-1/ETAR pathway antagonism. This resulted in significantly reduced liver-to-body weight ratio, plasma ALT levels, and α-SMA and collagen-I expression, indicating attenuation of liver fibrosis. In conclusion, our study demonstrates that the delivery of ERA using SPIONs enhances the therapeutic efficacy of ERA in vivo. This approach holds promise as a theranostic strategy for the MRI-based diagnosis and treatment of liver fibrosis.
Brucella Prostatitis: A Rare Manifestation of Fever of Unknown Origin, Detected by FDG PET/CT
Authors: Raza Abbas Mahdi, Komal Preet, Bhagwant Rai Mittal, Rajender Kumar, Harmandeep Singh, Sunil Taneja
Journal: Clinical Nuclear Medicine (2024)

Abstract FDG PET/CT is a well-documented imaging investigation to evaluate fever of unknown origin (FUO). Brucellosis is one of the causes of FUO, which can be missed as it requires a longer incubation period for growth on culture media. Rarely, it can involve the prostate. Here, we present a case of FUO with initial negative blood and urine cultures and no localizing signs or symptoms. 18 F-FDG PET/CT revealed hypermetabolism in the prostate and seminal vesicles. A repeat blood and urine culture showed the growth of Brucella species after 5 days of incubation, and the patient responded to Brucella-directed antibiotic therapy.
An Atypical Spindle Cell/Pleomorphic Lipomatous Tumor of the Thigh With a Difficult Imaging Diagnosis That Mimicked a Malignant Lipomatous Tumor
Authors: Taketsugu Fujibuchi, Jiro Ichikawa, Tomonori Kawasaki, Kojiro Onohara, Kaoru Aoki
Journal: Clinical Nuclear Medicine (2024)

Atypical spindle cell/pleomorphic lipomatous tumor is categorized as a benign lipomatous tumor, but various MRI findings pose accurate diagnostic challenges. In our case, both MRI and PET/CT scans indicated the possibility of atypical lipomatous tumor/well-differentiated liposarcoma or dedifferentiated liposarcoma. Needle biopsy suggested benign to low-grade malignancy; hence, we opted for the wide resection. The final diagnosis of atypical spindle cell/pleomorphic lipomatous tumor was confirmed through histopathology analysis, including immunohistochemistry and fluorescence in situ hybridization. Since achieving an accurate diagnosis solely through imaging can be challenging, histopathology remains essential.