Evaluation of metformin's effect on 5-fluorouracil-induced cardiotoxicity through cellular protection

Daru. 2026 Feb 4;34(1):11. doi: 10.1007/s40199-025-00589-4.

Abstract

Background: 5-Fluorouracil (5-FU) is a chemotherapeutic agent used primarily to treat various cancers. While it has been successful in improving cancer survival rates, 5-FU is also known to be cardiotoxic. Treatment options for patients experiencing 5-FU-induced cardiotoxicity are limited to standard heart failure medications.

Objectives: This study aims to investigate how metformin can reduce oxidative stress, apoptosis, and mitochondrial dysfunction in human cardiac myocyte (HCM) cells.

Methods: The optimal doses of 5-FU were determined using the MTT assay. Following exposure to 5-FU, HCM cells were treated with metformin for 48 h. The study measured the levels of reactive oxygen species (ROS), glutathione (GSH), and the activity of superoxide dismutase (SOD). Additionally, cytochrome c release and mitochondrial membrane potential were assessed in HCM cells. The expression levels of BAX and Bcl-2 were also examined, along with the activity of Caspase-3.

Results: The findings indicated that 5-FU significantly increased ROS levels, decreased GSH levels, and reduced SOD activity-effects that were mitigated by metformin. Furthermore, 5-FU markedly increased apoptosis and induced mitochondrial dysfunction, both of which were significantly reduced by metformin in a dose-dependent manner in HCM cells.

Conclusion: According to the present study results, metformin, through a reduction in oxidative stress, apoptosis, and mitochondrial malfunction, can have therapeutic potential in HCM cells toxicity induced by 5-FU.

Keywords: Cardiotoxicity; Fluorouracil; Metformin; Mitochondrial diseases.

MeSH terms

  • Antimetabolites, Antineoplastic* / adverse effects
  • Apoptosis / drug effects
  • Cardiotoxicity* / drug therapy
  • Cardiotoxicity* / etiology
  • Cardiotoxicity* / metabolism
  • Cardiotoxicity* / prevention & control
  • Caspase 3 / metabolism
  • Cell Line
  • Cell Survival / drug effects
  • Cytochromes c / metabolism
  • Dose-Response Relationship, Drug
  • Fluorouracil* / adverse effects
  • Fluorouracil* / toxicity
  • Glutathione / metabolism
  • Humans
  • Membrane Potential, Mitochondrial / drug effects
  • Metformin* / pharmacology
  • Myocytes, Cardiac* / drug effects
  • Myocytes, Cardiac* / metabolism
  • Oxidative Stress / drug effects
  • Reactive Oxygen Species / metabolism
  • Superoxide Dismutase / metabolism

Substances

  • Fluorouracil
  • Metformin
  • Reactive Oxygen Species
  • Glutathione
  • Superoxide Dismutase
  • Caspase 3
  • Antimetabolites, Antineoplastic
  • Cytochromes c