Doxorubicin (DOX) remains a cornerstone of chemotherapy but is limited by dose-dependent doxorubicin-induced cardiotoxicity (DIC). Recent evidence suggests that mitochondrial dysfunction, particularly oxidative stress and ferroptosis, drives DIC progression. While the flavonoid Calycosin (CAL) is known for its cardioprotective properties, the precise mechanism by which it maintains mitochondrial homeostasis remains elusive. This study aimed to investigate the effects of CAL against DIC and to explore the mechanisms by which CAL regulates mitochondrial integrity and iron homeostasis. Using both in vitro H9c2 cardiomyocytes and in vivo C57BL/6 mice, we demonstrate that CAL significantly restores cardiac contractility and reduces myocardial damage. Transcriptomic analysis indicated that CAL protected mitochondrial function and inhibited ferroptosis. Transmission Electron Microscopy (TEM) showed that CAL preserved mitochondrial structure. Assessments of the lipid peroxidation marker malondialdehyde (MDA) and superoxide dismutase (SOD) confirmed that CAL alleviated oxidative stress, while 8-OHdG staining verified its restoration of mitochondrial DNA integrity. Molecular docking identified the affinity of CAL with NRF2 and NRF1. CAL activated the NRF2/NRF1-TFAM axis both in vivo and in vitro, promoting mitochondrial biogenesis and respiratory function, while regulating iron homeostasis via FTMT and FPN. Knockdown or inhibition of NRF2/NRF1 abolished these protective effects of CAL. Our findings suggest that CAL acts as a dual-regulator of mitochondrial transcriptional machinery and iron metabolism, offering a novel therapeutic strategy to safeguard mitochondria against ferroptosis.

A high-salt and high-sugar (HS) diet is a major contributor to metabolic disorders, including lipid accumulation and oxidative stress. Lithocholic acid (LCA), as a key secondary bile acid, plays a crucial role in regulating metabolism and delaying aging. However, the specific molecular mechanisms underlying LCA’s protective effects against HS-induced metabolic damage remain unclear. In this study, using Caenorhabditis elegans as a model organism, we systematically investigated the protective effects of different concentrations of LCA against HS-induced metabolic damage and their regulatory mechanisms through lifespan analysis, oxidative stress phenotype testing, mitochondrial function assessment, intestinal barrier integrity evaluation, and molecular pathway validation. The aim was to explore the benefits of LCA against HS-induced metabolic abnormalities and to elucidate its potential molecular mechanisms. Result: In HS model, LCA treatment significantly improves overall health in nematodes, enhances motility, and extends lifespan. LCA effectively boosts antioxidant stress resistance in HS conditions, reduces reactive oxygen species (ROS) accumulation, positively regulates mitochondrial membrane potential to maintain stable mitochondrial function, and activates the AMPK signaling pathway. Furthermore, LCA mitigates HS-induced intestinal barrier damage, reduces intestinal permeability, and preserves gut structure and homeostasis. Concurrently, LCA alleviates HS-induced metabolic dysregulation by regulating the sbp-1/nhr-49 metabolic axis, ultimately exerting systemic protective effects through multiple targets and pathways. Conclusion: LCA may have anti-aging qualities, antioxidant properties and the capacity to raise metabolic levels when exposed to HS.