- Amphotericin B is a potent antifungal agent used in mammalian cell culture to prevent contamination by fungi, especially yeasts and molds. It primarily targets ergosterol in fungal membranes, disrupting membrane integrity and causing cell death. Although mammalian cell membranes do not contain ergosterol, Amphotericin B can also interact—albeit less strongly—with cholesterol, which shares structural similarities with ergosterol. This interaction raises concerns about Amphotericin B’s potential cytotoxic effects on mammalian cells, particularly at the mitochondrial level.
- Mitochondria are especially susceptible to membrane-disrupting agents because of their critical roles in energy production, membrane potential maintenance, and apoptosis regulation. Studies have shown that Amphotericin B can indirectly or directly impair mitochondrial function in mammalian cells by increasing membrane permeability and inducing oxidative stress. It may compromise mitochondrial membrane integrity, leading to the loss of mitochondrial membrane potential (ΔΨm), increased generation of reactive oxygen species (ROS), and activation of cell death pathways, including apoptosis. These effects are more pronounced at higher concentrations or with prolonged exposure to the drug.
- Moreover, Amphotericin B can impact mitochondrial bioenergetics by interfering with oxidative phosphorylation. Damage to mitochondrial membranes can affect the proton gradient essential for ATP synthesis, leading to reduced cellular energy production. Sensitive cell types—such as neurons, stem cells, or primary cultures—may show reduced viability, altered morphology, or functional decline even at standard culture concentrations (typically 0.25–2.5 µg/mL).
- To mitigate these risks, researchers are encouraged to use Amphotericin B only when fungal contamination is likely or confirmed, and for limited durations. The use of liposomal formulations or lower concentrations can reduce mitochondrial and general cytotoxicity while still maintaining antifungal efficacy. Additionally, experiments involving mitochondrial function, oxidative metabolism, or apoptosis should either avoid Amphotericin B or include proper controls to distinguish drug-related mitochondrial effects from experimental outcomes.
