bioRxiv Science⌕ Search
Home/Archive/bioRxiv

bioRxiv · 10.1101/2020.09.17.301689

Chemotherapeutic cardiotoxicity is associated with elevated β1-adrenergic receptor density

Gupta, M. K.·Martelli, E. E.·Stenson, K. T.·Naga Prasad, S. N.
View original source ↗Export metadata ↓

Abstract

ObjectiveTo understand the underlying pathways that promote cardiotoxicity following chemotherapy. BackgroundAnthracyclines are associated with cardiotoxicity which could be potentiated with use of complementary agents (like anti-ERBB2 inhibitors) which together afford robust anti-neoplastic effects. Anthracyclines lead to oxidative stress and thought to induce cardiotoxicity. However, interventions reducing oxidative stress in patients have been unsuccessful suggesting mechanisms beyond oxidative stress. Despite {beta}-adrenergic receptors ({beta}ARs) being key regulators of cardiac function, nothing is known about their role in chemotherapy-mediated cardiotoxicity. Methods{beta}1 and/or {beta}2-AR density was assessed in end-stage human heart failure patient samples either due to anthracycline cardiotoxicity or non-anthracycline dilated cardiomyopathy (DCM). Since ERBB2 inhibition is integral to overall chemotherapeutic arsenal, we assessed {beta}1- and/or {beta}2-AR density, cardiac function by echocardiography and immunohistochemistry in mice following ERBB2-specific inhibitor AG825. ResultsSelective increase in cardiac {beta}1AR density is observed in end-stage human heart failure patient samples due to anthracycline cardiotoxicity as well as in ERBB2 inhibitor-treated mice. ConclusionsElevated {beta}1AR density may be the key common underlying mechanism which is altered in response to chemotherapy promoting cardiac dilation of otherwise healthy hearts. HighlightsIn contrast to downregulation of {beta}1-adrenergic receptors ({beta}1AR) in end-stage human heart failure, anthracycline cardiotoxicity-mediated failure is associated with selective increase in {beta}1AR density. ERBB2 inhibitor (AG825) treatment in mice results in cardiac dilation and selective rise in {beta}1AR density showing that increased {beta}1AR density in the heart could be a common mechanism underlying cardiotoxicity.

Explore related subjects

pharmacology and toxicologyPreprint

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Gupta, M. K., Martelli, E. E., Stenson, K. T., Naga Prasad, S. N.. 2020-09-18. Chemotherapeutic cardiotoxicity is associated with elevated β1-adrenergic receptor density. https://doi.org/10.1101/2020.09.17.301689

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related preprints

bioRxiv2026

Denaturation-sensitive BRET probes enable intracellular thermal shift measurements across diverse protein targets and biomolecular complexes

Thermal shift assays have revolutionized drug discovery, but can be limited in sensitivity and scalability. Combining the unique attributes of differential scanning fluorimetry (DSF) and cellular thermal shift (CETSA), we report the methodological framework for the bioluminescence resonance energy transfer shift assay (BRETSA). BRETSA utilizes denaturation sensitive BRET probes, in combination with luciferase-tagged target proteins, to track and longitudinally record thermal shift in living cells. Denaturation profiles were successfully measured for over 500 globular proteins, spanning 24 target families in diverse cellular compartments. Among these, target engagement was confirmed for over 200 proteins; including validated drug targets as well as understudied members of the kinase subfamily. Leveraging orthosteric, allosteric, and covalent ligands in potency studies, this method offers improved sensitivity and scalability compared to other thermal shift methods. We extend the utility of BRETSA to interrogate target engagement at biomolecular complexes and query cooperative binding for molecular glues and emerging tricomplex drug modalities.

pharmacology and toxicology↗
bioRxiv2026

Peptide Sequence Determines the Efficacy of Single-Dose AAV-Vectorized GLP-1R Agonists in Diet-Induced Obese Mice

Background: Glucagon-like peptide-1 receptor (GLP-1R) agonists such as semaglutide produce substantial weight loss and glycemic improvement, but their long-term efficacy depends on sustained adherence to chronic dosing. Adeno-associated virus (AAV) gene therapy could, in principle, provide durable GLP-1R agonist (GLP-1RA) exposure from a single administration, but the degree of peptide engineering required for a vectorized GLP-1RA transgene to be efficacious in vivo is unknown. Methods: We generated four self-complementary AAV (scAAV) constructs encoding: native human GLP-1(7-36) (GLP-1), a DPP-IV-resistant Gly8-GLP-1(7-36) variant (Gly8), Exendin-4 (Ex4), or an Exendin-4 human IgG4 Fc fusion protein (Ex4-Fc). All four constructs were validated to secrete functional GLP-1R agonists in vitro using a conditioned-media potency assay. Subsequently, these constructs were packaged into PHP.eB capsids and administered as a single intravenous dose (5x1012 vg/kg) to diet-induced obese (DIO) mice alongside a vehicle control. Body weight, body composition, food intake, fasting plasma insulin, and oral glucose tolerance were assessed over a 3-week period. At the end of the study, tissues were harvested for assessments of plasma/liver lipids, tissue transgene transcript and peptide levels. Results: HEK293 cells transfected with the four AAV constructs all secreted active peptides/proteins as assessed by a cell-based GLP-1R activation assay, although the effective concentration of the GLP-1 constructs in the media spanned nearly four orders of magnitude 72 hours after transfection. In diet-induced obese (DIO) mice, Ex4 and Ex4-Fc vectors, but not GLP-1 or Gly8 vectors, produced significant reductions in body weight of up to 22.6% of starting body weight out to 21 days after a single dose. In addition, reductions in food intake, fat mass, and fasting insulin relative to vehicle were also observed for Ex4 and Ex4-Fc. Furthermore, Ex4-Fc improved oral glucose tolerance while reducing plasma cholesterol and liver triglycerides relative to vehicle. Although transcript levels did not differ appreciably among the four constructs in either brain or liver, measurable peptide product in plasma and brain lysate tracked the rank order of the in vitro supernatant screen, with GLP-1 and Gly8 groups indistinguishable from endogenous background. Conclusions: PHP.eB scAAV Ex4 and Ex4-Fc showed robust efficacy on multiple metabolic endpoints including weight loss and glucose tolerance. In contrast, vectorized GLP-1 and Gly8 showed no in vivo efficacy despite comparable levels of viral transcript in the brain and the liver. Vectorized GLP-1 and Gly8 also performed poorly compared to exendin-4-based constructs in vitro, suggesting that conditioned-media potency screening is a valid early filter for construct selection in vectorized-peptide AAV development. Engineering peptides to improve translation and secretion efficiency, in addition to circulating plasma stability, could further optimize vectorized GLP-1RA therapeutics.

pharmacology and toxicology↗
bioRxiv2026

Preclinical Evaluation of a Novel BOC-Modified Triazoloacridinone (TRA-01AR) in Combination with 5-Fluorouracil in Colorectal Cancer

5-Fluorouracil (5-FU) remains a cornerstone of colorectal cancer (CRC) therapy, yet its clinical efficacy is limited by resistance, systemic toxicity, and unfavorable pharmacokinetics. Strategies that enhance tumor sensitivity while maintaining tolerability are therefore of considerable interest. Here, we evaluated 5-FU in combination with two triazoloacridinones, C-1305 and a novel BOC-modified derivative, TRA-01AR, using integrated cellular, transcriptomic, bioenergetic, and in vivo approaches. Both compounds induced cytotoxic effects across cancer cell models and produced overlapping but distinct transcriptional responses, primarily affecting DNA replication and cell cycle pathways. Bioenergetic profiling revealed a shift toward oxidative phosphorylation accompanied by reduced glycolysis, indicating modulation of cellular metabolism relevant to chemotherapy response. Interestingly, TRA-01AR exhibited delayed cytotoxicity relative to C-1305, although the underlying mechanism remains to be defined. In vivo, the combination of 5-FU with C-1305 significantly reduced tumor weight in HT-29 xenografts, whereas 5-FU combined with TRA-01AR did not result in a statistically significant reduction compared to 5-FU alone. TRA-01AR was associated with a more favorable systemic profile and increased intratumoral blood flow compared with C-1305. Collectively, these findings indicate that triazoloacridinones modulate transcriptional and metabolic programs relevant to the 5-FU response. While C-1305 demonstrated greater antitumor activity under the tested conditions, TRA-01AR exhibited distinct biological effects, including improved tolerability and vascular modulation. Further studies are required to clarify TRA-01AR's mechanism of action and assess its potential relevance in CRC-specific therapies.

pharmacology and toxicology↗