Subacute exposure to black phosphorus quantum dots induces cardiac fibrosis and the potential role of gut microbiota.

Black phosphorus quantum dots (BPQDs) have been used as the nano-carrier in the field of biomedicine due to their excellent electronic conductivity, optical and thermoelectric properties. However, it is still lack of evaluation of the safety of BPQDs, specifically on the effects and mechanisms of BPQDs on heart. In this study, the specific pathogen-free male mice were orally administered with different doses of BPQDs (0.02, 0.1, 0.5 mg/kg) for 28 days. BPQDs exposure decreased the heart-body ratio and caused cardiac hypertrophy and fibrosis. Additionally, ferroptosis was observed in the cardiac tissue. The recent study has shown BPQDs oral exposure alter gut microbiota. Here, after exposure to 0.1 mg/kg BPQDs for 28 days, the germ-free mice showed neither cardiac injury nor ferroptosis. Taken together, the study demonstrates that BPQDs induce cardiac ferroptosis and fibrosis, possibly mediated by gut microbiota. This research may aid in enhancing understanding of the biosafety of BP nanomaterials and promoting the sustainable development of nanotechnology.