Sodium benzoate induces cardiotoxicity by suppressing the PI3K/AKT/GSK3β signaling axis: An integrated network toxicology and experimental study.

Abstract

Sodium benzoate (SB), a common food preservative, has raised concerns regarding multi-organ toxicity, but its cardiovascular effects remain unclear. Here, we combined network toxicology, molecular docking, and experimental validation to investigate SB-induced cardiotoxicity. The toxicity profile of SB was predicted using ProTox 3.0 and ADMETlab 3.0, which identified potential cardiotoxicity signals. Network analysis identified AKT1 as a hub target, with functional enrichment implicating the PI3K-AKT apoptotic cascade, and molecular dynamics (MD) simulations confirmed stable SB-AKT1 binding. To experimentally validate these predictions, we assessed cardiac function and PI3K/AKT signaling in SB-exposed mice and AC16 cardiomyocytes. In vivo, SB impaired cardiac function and disrupted myocardial morphology, accompanied by elevated serum LDH, CK-MB, and DHE levels. In vitro, SB reduced cardiomyocyte viability, with equimolar NaCl controls confirming specific toxicity of the benzoate moiety. Mechanistically, SB suppressed PI3K/AKT phosphorylation and its downstream GSK3β pro-survival axis, leading to mitochondrial depolarization, BAX/BCL2 imbalance, and Cleaved-Caspase3 activation, collectively indicating mitochondrial apoptosis. mTOR phosphorylation remained unchanged, suggesting that mTOR may not be a functional downstream effector in this model. Notably, although SB elevated ROS production, ROS scavenging failed to restore AKT signaling or rescue cell death, whereas direct AKT activation reversed mitochondrial depolarization and apoptosis, confirming that AKT inhibition, rather than oxidative stress, is the primary driver. Collectively, these findings identify ROS-independent suppression of the PI3K/AKT/GSK3β axis as a key mechanism underlying SB-induced cardiotoxicity, extending its toxicological profile to the cardiovascular system.