Johnson, R;Ahmed, S;Solanki, R;Wostear, F;Afewerki, T;Warren, D;
| DOI: 10.1136/heartjnl-2022-bcs.198
Rationale DNA damage accumulation is a hallmark of vascular smooth muscle cell (VSMC) ageing. Importantly, VSMC DNA damage accumulation and ageing has been implicated in the progression of cardiovascular disease (CVD), including atherosclerosis and vascular calcification. Chemotherapy drugs used in the treatment of many cancers are known to induce DNA damage in cardiovascular cells and accelerate CVD. Histone deacetylase (HDAC) inhibitors are drugs being investigated for novel treatments of many cancers. HDACs perform many vital functions in cells; HDAC6 is known to deacetylate alpha-tubulin to regulate microtubule stability and flexibility. We have recently shown that microtubule stability regulates both VSMC morphology and contractility. Therefore, in this study we investigate the impact of HDAC6 inhibition upon VSMC function. Methodology We use polyacrylamide hydrogels (PAHs)
Eder, RA;van den Boomen, M;Yurista, SR;Rodriguez-Aviles, YG;Islam, MR;Chen, YI;Trager, L;Coll-Font, J;Cheng, L;Li, H;Rosenzweig, A;Wrann, CD;Nguyen, CT;
PMID: 35787681 | DOI: 10.1038/s42003-022-03635-y
Both exercise-induced molecular mechanisms and physiological cardiac remodeling have been previously studied on a whole heart level. However, the regional microstructural tissue effects of these molecular mechanisms in the heart have yet to be spatially linked and further elucidated. We show in exercised mice that the expression of CITED4, a transcriptional co-regulator necessary for cardioprotection, is regionally heterogenous in the heart with preferential significant increases in the lateral wall compared with sedentary mice. Concordantly in this same region, the heart's local microstructural tissue helicity is also selectively increased in exercised mice. Quantification of CITED4 expression and microstructural tissue helicity reveals a significant correlation across both sedentary and exercise mouse cohorts. Furthermore, genetic deletion of CITED4 in the heart prohibits regional exercise-induced microstructural helicity remodeling. Taken together, CITED4 expression is necessary for exercise-induced regional remodeling of the heart's microstructural helicity revealing how a key molecular regulator of cardiac remodeling manifests into downstream local tissue-level changes.
The Canadian journal of cardiology
Eguchi, S;Sparks, MA;Sawada, H;Lu, HS;Daugherty, A;Zhuo, JL;
PMID: 37394059 | DOI: 10.1016/j.cjca.2023.06.421
The renin-angiotensin system (RAS) is an essential hormonal system involved in water and sodium reabsorption, renal blood flow regulation, and arterial constriction. Systemic stimulation of the RAS with infusion of the main peptide angiotensin II (Ang II) in animals as well as pathological elevation of renin (i.e renovascular hypertension) to increase circulatory Ang II in humans ultimately lead to hypertension and end-organ damage. In addition to hypertension, accumulating evidence support that the Ang II type 1 receptor exerts a critical role in cardiovascular and kidney diseases independent of blood pressure elevation. In the last two decades, the identification of an increased number of peptides and receptors has facilitated the concept that the RAS has both detrimental and beneficial effects on the cardiovascular system depending on which RAS components are activated. For example, angiotensin 1-7 and Ang II type 2 receptors act as a counter-regulatory system against the classical RAS by mediating vasodilation. While the RAS as an endocrine system for regulation of blood pressure is well established, there remain many unanswered questions and controversial findings regarding blood pressure regulation and pathophysiological regulation of cardiovascular diseases at the tissue level. This review article will include the latest knowledge gleaned from cell type-selective gene deleted mice regarding cell type-specific roles of AngII receptors and discuss their significance in health and diseases. In particular, we focus on the roles of these receptors expressed in vascular, cardiac, and kidney epithelial cells.
Rammah, M;Théveniau-Ruissy, M;Sturny, R;Rochais, F;Kelly, RG;
PMID: 36205127 | DOI: 10.1161/CIRCRESAHA.122.320766
The arterial pole of the heart is a hotspot for life-threatening forms of congenital heart defects (CHDs). Development of this cardiac region occurs by addition of Second Heart Field (SHF) progenitor cells to the embryonic outflow tract (OFT) and subsequently the base of the ascending aorta and pulmonary trunk. Understanding the cellular and genetic mechanisms driving arterial pole morphogenesis is essential to provide further insights into the cause of CHDs.A synergistic combination of bioinformatic analysis and mouse genetics as well as embryo and explant culture experiments were used to dissect the cross-regulatory transcriptional circuitry operating in future subaortic and subpulmonary OFT myocardium.Here, we show that the lipid sensor PPARγ (peroxisome proliferator-activated receptor gamma) is expressed in future subpulmonary myocardium in the inferior wall of the OFT and that PPARγ signaling-related genes display regionalized OFT expression regulated by the transcription factor TBX1 (T-box transcription factor 1). Modulating PPARγ activity in ex vivo cultured embryos treated with a PPARγ agonist or antagonist or deleting Pparγ in cardiac progenitor cells using Mesp1-Cre reveals that Pparγ is required for addition of future subpulmonary myocardium and normal arterial pole development. Additionally, the non-canonical DLK1 (delta-like noncanonical Notch ligand 1)/NOTCH (Notch receptor 1)/HES1 (Hes family bHLH transcription factor 1) pathway negatively regulates Pparγ in future subaortic myocardium in the superior OFT wall.Together these results identify Pparγ as a regulator of regional transcriptional identity in the developing heart, providing new insights into gene interactions involved in congenital heart defects.
Medvedev, R;Turner, D;Gorelik, J;Alvarado, F;Bondarenko, V;Glukhov, A;
| DOI: 10.1016/j.bpj.2022.11.1392
Atrial fibrillation (AF) is commonly observed in patients with hypertension and is associated with pathologically elevated cardiomyocyte stretch. AF triggers have been linked to subcellular Ca2+ abnormalities, while their association with stretch remains elusive. Caveolae are mechanosensitive membrane structures, that play a role in both Ca2+ and cyclic adenosine monophosphate (cAMP) signaling. Therefore, caveolae could provide a mechanistic connection between cardiomyocyte stretch, Ca2+ mishandling, and AF. In isolated mouse atrial myocytes, cell stretch was mimicked by hypotonic swelling, which increased cell width (by ∼30%, p
Journal of the American Heart Association
Xue, Q;Zhang, Q;Guo, Z;Wu, L;Chen, Y;Chen, Z;Yang, K;Cao, J;
PMID: 36789845 | DOI: 10.1161/JAHA.122.026160
Background Therapeutic hypothermia has a beneficial effect on cardiac function after acute myocardial infarction, but the exact mechanism is still unclear. Recent research has suggested that microRNAs participate in acute myocardial infarction to regulate cardiomyocyte survival. This study aimed to explore the ability of hypothermia-regulated microRNA-483-3p (miR-483-3p) to inhibit hypoxia-induced myocardial infarction. Methods and Results Primary cardiomyocytes were cultured under hypoxia at 32 °C to mimic therapeutic hypothermia, and the differentially expressed microRNAs were determined by RNA sequencing. Therapeutic hypothermia recovered hypoxia-induced increases in apoptosis, decreases in ATP levels, and decreases in miR-483-3p expression. Overexpression of miR-483-3p exhibited effects similar to those of therapeutic hypothermia on hypoxia in the treatment of cardiomyocytes to associate with maintaining the mitochondrial membrane potential, and cyclin-dependent kinase 9 (Cdk9) was identified as a target gene with downregulated expression by miR-483-3p. Knockdown of Cdk9 also promoted cardiac survival, ATP production, and mitochondrial membrane potential stability under hypoxia. In vivo, the expression of miR-483-3p and Cdk9 was tested in the cardiac tissue of the mice with acute myocardial infarction, and the expression of miR-483-3p decreased and Cdk9 increased in the region of myocardial infarction. However, miR-483-3p was overexpressed with lentivirus, which suppressed apoptosis, infarct size (miR-483-3p, 22.00±4.04% versus negative control, 28.57±5.44%, P<0.05), and Cdk9 expression to improve cardiac contractility. Conclusions MiR-483-3p antagonizes hypoxia, leading to cardiomyocyte injury by targeting Cdk9, which is a new mechanism of therapeutic hypothermia.
The Journal of clinical investigation
Goodyer, WR;Beyersdorf, BM;Duan, L;van den Berg, NS;Mantri, S;Galdos, FX;Puluca, N;Buikema, JW;Lee, S;Salmi, D;Robinson, ER;Rogalla, S;Cogan, DP;Khosla, C;Rosenthal, EL;Wu, SM;
PMID: 35951416 | DOI: 10.1172/JCI156955
Accidental injury to the cardiac conduction system (CCS), a network of specialized cells embedded within the heart and indistinguishable from the surrounding heart muscle tissue, is a major complication in cardiac surgeries. Here, we addressed this unmet need by engineering targeted antibody-dye conjugates directed against CCS, allowing for the visualization of the CCS in vivo following a single intravenous injection in mice. These optical imaging tools showed high sensitivity, specificity, and resolution, with no adverse effects to CCS function. Further, with the goal of creating a viable prototype for human use, we generated a fully human monoclonal Fab, that similarly targets the CCS with high specificity. We demonstrate that, when conjugated to an alternative cargo, this Fab can also be used to modulate CCS biology in vivo providing a proof-of-principle for targeted cardiac therapeutics. Finally, in performing differential gene expression analyses of the entire murine CCS at single-cell resolution, we uncovered and validated a suite of additional cell surface markers that can be used to molecularly target the distinct subcomponents of the CCS, each prone to distinct life-threatening arrhythmias. These findings lay the foundation for translational approaches targeting the CCS for visualization and therapy in cardiothoracic surgery, cardiac imaging and arrhythmia management.
Worssam, MD;Lambert, J;Oc, S;Taylor, JC;Taylor, AL;Dobnikar, L;Chappell, J;Harman, JL;Figg, NL;Finigan, A;Foote, K;Uryga, AK;Bennett, MR;Spivakov, M;Jørgensen, HF;
PMID: 35994249 | DOI: 10.1093/cvr/cvac138
Quiescent, differentiated adult vascular smooth muscle cells (VSMCs) can be induced to proliferate and switch phenotype. Such plasticity underlies blood vessel homeostasis and contributes to vascular disease development. Oligoclonal VSMC contribution is a hallmark of end-stage vascular disease. Here we aim to understand cellular mechanisms underpinning generation of this VSMC oligoclonality.We investigate the dynamics of VSMC clone formation using confocal microscopy and single cell transcriptomics in VSMC-lineage-traced animal models. We find that activation of medial VSMC proliferation occurs at low frequency after vascular injury and that only a subset of expanding clones migrate, which together drives formation of oligoclonal neointimal lesions. VSMC contribution in small atherosclerotic lesions is typically from one or two clones, similar to observations in mature lesions. Low frequency (<0.1%) of clonal VSMC proliferation is also observed in vitro. Single-cell RNA-sequencing revealed progressive cell state changes across a contiguous VSMC population at onset of injury-induced proliferation. Proliferating VSMCs mapped selectively to one of two distinct trajectories and were associated with cells showing extensive phenotypic switching. A proliferation-associated transitory state shared pronounced similarities with atypical SCA1+ VSMCs from uninjured mouse arteries and VSMCs in healthy human aorta. We show functionally that clonal expansion of SCA1+ VSMCs from healthy arteries occurs at higher rate and frequency compared to SCA1- cells.Our data suggest that activation of proliferation at low frequency is a general, cell-intrinsic feature of VSMCs. We show that rare VSMCs in healthy arteries display VSMC phenotypic switching akin to that observed in pathological vessel remodelling and that this is a conserved feature of mouse and human healthy arteries. The increased proliferation of modulated VSMCs from healthy arteries suggests that these cells respond more readily to disease-inducing cues and could drive oligoclonal VSMC expansion.
Nature Cardiovascular Research
Yamada, S;Ko, T;Hatsuse, S;Nomura, S;Zhang, B;Dai, Z;Inoue, S;Kubota, M;Sawami, K;Yamada, T;Sassa, T;Katagiri, M;Fujita, K;Katoh, M;Ito, M;Harada, M;Toko, H;Takeda, N;Morita, H;Aburatani, H;Komuro, I;
| DOI: 10.1038/s44161-022-00140-7
The underlying mechanisms of ventricular remodeling after myocardial infarction (MI) remain largely unknown. In this study, we performed an integrative analysis of spatial transcriptomics and single-nucleus RNA sequencing (snRNA-seq) in a murine MI model and found that mechanical stress-response genes are expressed at the border zone and play a critical role in left ventricular remodeling after MI. An integrative analysis of snRNA-seq and spatial transcriptome of the heart tissue after MI identified the unique cluster that appeared at the border zone in an early stage, highly expressing mechano-sensing genes, such as Csrp3. AAV9-mediated gene silencing and overexpression of Csrp3 demonstrated that upregulation of Csrp3 plays critical roles in preventing cardiac remodeling after MI by regulation of genes associated with mechano-sensing. Overall, our study not only provides an insight into spatiotemporal molecular changes after MI but also highlights that the mechano-sensing genes at the border zone act as adaptive regulators of left ventricular remodeling.
The Journal of clinical investigation
Yerra, VG;Batchu, SN;Kaur, H;Kabir, MDG;Liu, Y;Advani, SL;Tran, DT;Sadeghian, S;Sedrak, P;Billia, F;Kuzmanov, U;Gramolini, AO;Qasrawi, DO;Petrotchenko, EV;Borchers, CH;Connelly, KA;Advani, A;
PMID: 37115698 | DOI: 10.1172/JCI161453
Inflammation promotes adverse ventricular remodeling, a common antecedent of heart failure. Here, we set out to determine how inflammatory cells affect cardiomyocytes in the remodeling heart. Pathogenic cardiac macrophages induced an IFN response in cardiomyocytes, characterized by upregulation of the ubiquitin-like protein IFN-stimulated gene 15 (ISG15), which posttranslationally modifies its targets through a process termed ISGylation. Cardiac ISG15 is controlled by type I IFN signaling, and ISG15 or ISGylation is upregulated in mice with transverse aortic constriction or infused with angiotensin II; rats with uninephrectomy and DOCA-salt, or pulmonary artery banding; cardiomyocytes exposed to IFNs or CD4+ T cell-conditioned medium; and ventricular tissue of humans with nonischemic cardiomyopathy. By nanoscale liquid chromatography-tandem mass spectrometry, we identified the myofibrillar protein filamin-C as an ISGylation target. ISG15 deficiency preserved cardiac function in mice with transverse aortic constriction and led to improved recovery of mouse hearts ex vivo. Metabolomics revealed that ISG15 regulates cardiac amino acid metabolism, whereas ISG15 deficiency prevented misfolded filamin-C accumulation and induced cardiomyocyte autophagy. In sum, ISG15 upregulation is a feature of pathological ventricular remodeling, and protein ISGylation is an inflammation-induced posttranslational modification that may contribute to heart failure development by altering cardiomyocyte protein turnover.
Rypdal, KB;Olav Melleby, A;Robinson, EL;Li, J;Palmero, S;Seifert, DE;Martin, D;Clark, C;López, B;Andreassen, K;Dahl, CP;Sjaastad, I;Tønnessen, T;Stokke, MK;Louch, WE;González, A;Heymans, S;Christensen, G;Apte, SS;Lunde, IG;
PMID: 36539599 | DOI: 10.1038/s42003-022-04361-1
Heart failure is a major cause of morbidity and mortality worldwide, and can result from pressure overload, where cardiac remodelling is characterized by cardiomyocyte hypertrophy and death, fibrosis, and inflammation. In failing hearts, transforming growth factor (TGF)β drives cardiac fibroblast (CFB) to myofibroblast differentiation causing excessive extracellular matrix production and cardiac remodelling. New strategies to target pathological TGFβ signalling in heart failure are needed. Here we show that the secreted glycoprotein ADAMTSL3 regulates TGFβ in the heart. We found that Adamtsl3 knock-out mice develop exacerbated cardiac dysfunction and dilatation with increased mortality, and hearts show increased TGFβ activity and CFB activation after pressure overload by aortic banding. Further, ADAMTSL3 overexpression in cultured CFBs inhibits TGFβ signalling, myofibroblast differentiation and collagen synthesis, suggesting a cardioprotective role for ADAMTSL3 by regulating TGFβ activity and CFB phenotype. These results warrant future investigation of the potential beneficial effects of ADAMTSL3 in heart failure.
Bi, Q;Wang, C;Cheng, G;Chen, N;Wei, B;Liu, X;Li, L;Lu, C;He, J;Weng, Y;Yin, C;Lin, Y;Wan, S;Zhao, L;Xu, J;Wang, Y;Gu, Y;Shen, XZ;Shi, P;
PMID: 35863346 | DOI: 10.1016/j.immuni.2022.06.018
Although many studies have addressed the regulatory circuits affecting neuronal activities, local non-synaptic mechanisms that determine neuronal excitability remain unclear. Here, we found that microglia prevented overactivation of pre-sympathetic neurons in the hypothalamic paraventricular nucleus (PVN) at steady state. Microglia constitutively released platelet-derived growth factor (PDGF) B, which signaled via PDGFRα on neuronal cells and promoted their expression of Kv4.3, a key subunit that conducts potassium currents. Ablation of microglia, conditional deletion of microglial PDGFB, or suppression of neuronal PDGFRα expression in the PVN elevated the excitability of pre-sympathetic neurons and sympathetic outflow, resulting in a profound autonomic dysfunction. Disruption of the PDGFBMG-Kv4.3Neuron pathway predisposed mice to develop hypertension, whereas central supplementation of exogenous PDGFB suppressed pressor response when mice were under hypertensive insult. Our results point to a non-immune action of resident microglia in maintaining the balance of sympathetic outflow, which is important in preventing cardiovascular diseases.