Abstract
Orthosteric β-blockers represent the leading pharmacological intervention for managing heart diseases owing to their ability to competitively antagonize β-adrenergic receptors (βARs). However, their use is often limited by the development of adverse effects such as fatigue, hypotension, and reduced exercise capacity, due in part to the nonselective inhibition of multiple βAR subtypes. These challenges are particularly problematic in treating catecholaminergic polymorphic ventricular tachycardia (CPVT), a disease characterized by lethal tachyarrhythmias directly triggered by cardiac β1AR activation. To identify small molecule allosteric modulators of the β1AR that could offer enhanced subtype specificity and robust functional antagonism of β1AR-mediated signaling, we conducted a DNA-encoded small molecule library screen and discovered Compound 11 (C11). C11 selectively potentiates the binding affinity of orthosteric agonists to the β1AR while potently inhibiting downstream signaling following β1AR activation. Moreover, C11 prevents agonist-induced spontaneous contractile activity, Ca2+ release events, and exercise-induced ventricular tachycardia in the CSQ2–/– murine model of CPVT. Collectively, our studies demonstrate that C11 belongs to an emerging class of allosteric modulators termed PAM-antagonists that positively modulate agonist binding but block downstream function. With unique pharmacological properties and selective functional antagonism of β1AR-mediated signaling, C11 represents a promising therapeutic candidate for the treatment of CPVT and other forms of cardiac disease associated with excessive β1AR activation.
Authors
Alyssa Grogan, Robin M. Perelli, Seungkirl Ahn, Haoran Jiang, Arun Jyothidasan, Damini Sood, Chongzhao You, David I. Israel, Alex Shaginian, Qiuxia Chen, Jian Liu, Jialu Wang, Jan Steyaert, Alem W. Kahsai, Andrew P. Landstrom, Robert J. Lefkowitz, Howard A. Rockman
Abstract
Lactylation, a post-translational modification derived from glycolysis, plays a pivotal role in ischemic heart diseases. Neutrophils are predominantly glycolytic cells that trigger intensive inflammation of myocardial ischemia reperfusion (MI/R). However, whether lactylation regulates neutrophil function during MI/R remains unknown. Employing lactyl proteomics analysis, S100a9 was lactylated at lysine 26 (S100a9K26la) in neutrophils, with elevated levels observed in both acute myocardial infarction (AMI) patients and MI/R model mice. S100a9K26la was demonstrated driving the development of MI/R using mutant knock-in mice. Mechanistically, lactylated S100a9 translocated to the nucleus of neutrophils, where it binded to the promoters of migration-related genes, thereby enhancing their transcription as a co-activator and promoting neutrophil migration and cardiac recruitment. Additionally, lactylated S100a9 was released during NETosis, leading to cardiomyocyte death by disrupting mitochondrial function. The enzyme dihydrolipoyllysine-residue acetyltransferase (DLAT) was identified as the lactyltransferase facilitating neutrophil S100a9K26la post-MI/R, a process that could be restrained by α-lipoic acid. Consistently, targeting DLAT/S100a9K26la axis suppressed neutrophil burden and improved cardiac function post-MI/R. In patients with AMI, elevated S100a9K26la levels in plasma were positively correlated with cardiac death. These findings highlight S100a9 lactylation as a potential therapeutic target for MI/R and as a promising biomarker for evaluating poor prognosis of MI/R.
Authors
Xiaoqi Wang, Xiangyu Yan, Ge Mang, Yujia Chen, Shuang Liu, Jiayu Sui, Zhonghua Tong, Penghe Wang, Jingxuan Cui, Qiannan Yang, Yafei Zhang, Dongni Wang, Ping Sun, Weijun Song, Zexi Jin, Ming Shi, Peng Zhao, Jia Yang, Mingyang Liu, Naixin Wang, Tao Chen, Yong Ji, Bo Yu, Maomao Zhang
Abstract
Plasminogen activator inhibitor-1 (PAI-1), encoded by SERPINE1, contributes to age-related cardiovascular diseases (CVD) and other aging-related pathologies. Humans with a heterozygous loss-of-function SERPINE1 variant exhibit protection against aging and cardiometabolic dysfunction. We engineered a mouse model mimicking the human mutation (Serpine1TA700/+) and compared cardiovascular responses with wild-type littermates. Serpine1TA700/+ mice lived 20% longer than littermate controls. Under L-NG-Nitro-arginine methyl ester (L-NAME)-induced vascular stress, Serpine1TA700/+ mice exhibited diminished pulse wave velocity (PWV), lower systolic hypertension (SBP), and preserved left ventricular diastolic function compared to controls. Conversely, PAI-1-overexpressing mice exhibited measurements indicating accelerated cardiovascular aging. Single cell transcriptomics of Serpine1TA700/+ aortas revealed a vascular-protective mechanism with downregulation of extracellular matrix regulators Ccn1 and Itgb1. Serpine1TA700/+ aortas were also enriched in a cluster of smooth muscle cells that exhibited plasticity. Finally, PAI-1 pharmacological inhibition normalized SBP and reversed L-NAME-induced PWV elevation. These findings demonstrate that PAI-1 reduction protects against cardiovascular aging-related phenotypes, while PAI-1 excess promotes vascular pathological changes. Taken together, PAI-1 inhibition represents a promising strategy to mitigate age-related CVD.
Authors
Alireza Khoddam, Anthony Kalousdian, Mesut Eren, Saul Soberanes, Andrew Decker, Elizabeth J. Lux, Benjamin W. Zywicki, Brian Dinh, Bedirhan Boztepe, Baljash S. Cheema, Carla M. Cuda, Hiam Abdala-Valencia, Arun Sivakumar, Toshio Miyata, Lisa D. Wilsbacher, Douglas E. Vaughan
Abstract
Background. Statin therapy lowers the risk of major adverse cardiovascular events (MACE) among people with HIV (PWH). Residual risk pathways contributing to excess MACE beyond low-density lipoprotein cholesterol (LDL-C) are not well understood. Our objective was to evaluate the association of statin responsive and other inflammatory and metabolic pathways to MACE in the Randomized Trial to Prevent Vascular Events in HIV (REPRIEVE). Methods. Cox proportional hazards models were used to assess the relationship between MACE and proteomic measurements at study entry and year 2 adjusting for time-updated statin use and baseline 10-year atherosclerotic cardiovascular disease risk score. We built a machine learning (ML) model to predict MACE using baseline proteins values with significant associations. Results. In 765 individuals (age: 50.8±5.9 years, 82% males) among 7 proteins changing with statin vs. placebo, angiopoietin-related protein 3 (ANGPTL3) related most strongly to MACE (aHR: 2.31 per 2-fold higher levels; 95%CI: 1.11-4.80; p=0.03), such that lower levels of ANGPTL3 achieved with statin therapy were associated with lower MACE risk. Among 248 proteins not changing in response to statin therapy, 26 were associated with MACE at FDR<0.05. These proteins represented predominantly humoral immune response, leukocyte chemotaxis, and cytokine pathways. Our proteomic ML model achieved a 10-fold cross-validated c-index of 0.74±0.11 to predict MACE, improving on models using traditional risk prediction scores only (c-index: 0.61±0.18). Conclusions. ANGPTL3, as well as key inflammatory pathways may contribute to residual risk of MACE among PWH, beyond LDL-C. Trial registration. ClinicalTrials.gov: NCT02344290. Funding. NIH, Kowa, Gilead Sciences, ViiV.
Authors
Márton Kolossváry, Irini Sereti, Markella V. Zanni, Carl J. Fichtenbaum, Judith A Aberg, Gerald S. Bloomfield, Carlos D. Malvestutto, Judith S. Currier, Sarah M. Chu, Marissa R. Diggs, Alex B. Lu, Christopher deFilippi, Borek Foldyna, Sara McCallum, Craig A. Sponseller, Michael T. Lu, Pamela S. Douglas, Heather J. Ribaudo, Steven K. Grinspoon
Abstract
Authors
Alireza Raissadati, Xuanyu Zhou, Harrison Chou, Yuhsin Vivian Huang, Shaheen Khatua, Yin Sun, Anne Xu, Sharon Loa, Arturo Hernandez, Han Zhu, Sean M. Wu
Abstract
Platelet hyperreactivity increases the risk of cardiovascular thrombosis in diabetes and failure of antiplatelet drug therapies. Elevated basal and agonist-induced calcium flux is a fundamental cause of platelet hyperreactivity in diabetes; however, the mechanisms responsible for this remain largely unknown. Using a high-sensitivity, unbiased proteomic platform, we consistently detected over 2,400 intracellular proteins and identified proteins that were differentially released by platelets in type 2 diabetes. We identified that SEC61 translocon subunit β (SEC61B) was increased in platelets from humans and mice with hyperglycemia and in megakaryocytes from mice with hyperglycemia. SEC61 is known to act as an endoplasmic reticulum (ER) calcium leak channel in nucleated cells. Using HEK293 cells, we showed that SEC61B overexpression increased calcium flux into the cytosol and decreased protein synthesis. Concordantly, platelets in hyperglycemic mice mobilized more calcium and had decreased protein synthesis. Platelets in both humans and mice with hyperglycemia had increased ER stress. ER stress induced the expression of platelet SEC61B and increased cytosolic calcium. Inhibition of SEC61 with anisomycin decreased platelet calcium flux and inhibited platelet aggregation in vitro and in vivo. These studies demonstrate the existence of a mechanism whereby ER stress–induced upregulation of platelet SEC61B leads to increased cytosolic calcium, potentially contributing to platelet hyperreactivity in diabetes.
Authors
Yvonne X. Kong, Rajan Rehan, Cesar L. Moreno, Søren Madsen, Yunwei Zhang, Huiwen Zhao, Miao Qi, Callum B. Houlahan, Siân P. Cartland, Declan Robertshaw, Vincent Trang, Frederick Jun Liang Ong, Michael Liu, Edward Cheng, Imala Alwis, Alexander Dupuy, Michelle Cielesh, Kristen C. Cooke, Meg Potter, Jacqueline Stöckli, Grant Morahan, Maggie L. Kalev-Zylinska, Matthew T. Rondina, Sol Schulman, Jean Y. H. Yang, G. Gregory Neely, Simone M. Schoenwaelder, Shaun P. Jackson, David E. James, Mary M. Kavurma, Samantha L. Hocking, Stephen M. Twigg, James C. Weaver, Mark Larance, Freda H. Passam
Abstract
Direct interaction of RAS with the PI3K p110α subunit mediates RAS-driven tumor development: however, it is not clear how p110α/RAS-dependant signaling mediates interactions between tumors and host tissues. Here, using a murine tumor cell transfer model, we demonstrated that disruption of the interaction between RAS and p110α within host tissue reduced tumor growth and tumor-induced angiogenesis, leading to improved survival of tumor-bearing mice, even when this interaction was intact in the transferred tumor. Furthermore, functional interaction of RAS with p110α in host tissue was required for efficient establishment and growth of metastatic tumors. Inhibition of RAS and p110α interaction prevented proper VEGF-A and FGF-2 signaling, which are required for efficient angiogenesis. Additionally, disruption of the RAS and p110α interaction altered the nature of tumor-associated macrophages, inducing expression of markers typical for macrophage populations with reduced tumor-promoting capacity. Together, these results indicate that a functional RAS interaction with PI3K p110α in host tissue is required for the establishment of a growth-permissive environment for the tumor, particularly for tumor-induced angiogenesis. Targeting the interaction of RAS with PI3K has the potential to impair tumor formation by altering the tumor-host relationship, in addition to previously described tumor cell–autonomous effects.
Authors
Miguel Manuel Murillo, Santiago Zelenay, Emma Nye, Esther Castellano, Francois Lassailly, Gordon Stamp, Julian Downward
Abstract
Fibroblast growth factor homologous factors (FHFs) bind to the cytoplasmic carboxy terminus of voltage-gated sodium channels (VGSCs) and modulate channel function. Variants in FHFs or VGSCs perturbing that bimolecular interaction are associated with arrhythmias. Like some channel auxiliary subunits, FHFs exert additional cellular regulatory roles, but whether these alternative roles affect VGSC regulation is unknown. Using a separation-of-function strategy, we show that a structurally guided, binding incompetent mutant FGF13 (the major FHF in mouse heart) confers complete regulation of VGSC steady-state inactivation (SSI), the canonical effect of FHFs. In cardiomyocytes isolated from Fgf13 knockout mice, expression of the mutant FGF13 completely restores wild-type regulation of SSI. FGF13 regulation of SSI derives from effects on local accessible membrane cholesterol, which is unexpectedly polarized and concentrated in cardiomyocytes at the intercalated disc (ID) where most VGSCs localize. Fgf13 knockout eliminates the polarized cholesterol distribution and causes loss of VGSCs from the ID. Moreover, we show that the previously described FGF13-dependent stabilization of VGSC currents at elevated temperatures depends on the cholesterol mechanism. These results provide new insights into how FHFs affect VGSCs and alter the canonical model by which channel auxiliary subunits exert influence.
Authors
Aravind R. Gade, Mattia Malvezzi, Lala Tanmoy Das, Maiko Matsui, Cheng-I J. Ma, Keon Mazdisnian, Steven O. Marx, Frederick R. Maxfield, Geoffrey S. Pitt
Abstract
While weight loss is highly recommended for those with obesity, >60% will regain their lost weight. This weight cycling is associated with elevated risk of cardiovascular disease, relative to never having lost weight. How weight loss/regain directly influence atherosclerotic inflammation is unknown. Thus, we studied short-term caloric restriction (stCR) in obese hypercholesterolemic mice, without confounding effects from changes in diet composition. Weight loss was found to promote atherosclerosis resolution independent of plasma cholesterol. From single-cell RNA-sequencing and subsequent mechanistic studies, this can be partly attributed to a unique subset of macrophages accumulating with stCR in epididymal white adipose tissue (eWAT) and atherosclerotic plaques. These macrophages, distinguished by high expression of Fcgr4, help to clear necrotic cores in atherosclerotic plaques. Conversely, weight regain (WR) following stCR accelerated atherosclerosis progression with disappearance of Fcgr4+ macrophages from eWAT and plaques. Furthermore, WR caused reprogramming of immune progenitors, sustaining hyper-inflammatory responsiveness. In summary, we have developed a model to investigate the inflammatory effects of weight cycling on atherosclerosis and the interplay between adipose tissue, bone marrow, and plaques. The findings suggest potential approaches to promote atherosclerosis resolution in obesity and weight cycling through induction of Fcgr4+ macrophages and inhibition of immune progenitor reprogramming.
Authors
Bianca Scolaro, Franziska Krautter, Emily J. Brown, Aleepta Guha Ray, Rotem Kalev-Altman, Marie Petitjean, Sofie Delbare, Casey Donahoe, Stephanie Pena, Michela L. Garabedian, Cyrus A. Nikain, Maria Laskou, Ozlem Tufanli, Carmen Hannemann, Myriam Aouadi, Ada Weinstock, Edward A. Fisher
Abstract
Authors
Macee C. Owen, Vinay R. Penna, Hao Dun, Wenjun Li, Benjamin J. Kopecky, Kenneth M. Murphy, Daniel Kreisel, Kory J. Lavine
Copyright © 2025 American Society for Clinical Investigation
ISSN: 0021-9738 (print), 1558-8238 (online)