Cannabidiol does not cause DNA double-strand breaks in a human liver-derived cell model

Abstract Background Cannabidiol (CBD) is a non-psychoactive cannabinoid with potential therapeutic applications, including anti-inflammatory, analgesic, and anticancer effects. However, experts raised concerns about its potential to induce DNA damage and chromosomal aberrations at low concentrations. Notably, these studies used liver cell lines, which may not fully reflect the metabolic processing of CBD, potentially limiting the generalizability of their findings. This study investigated the short time effects of CBD on DNA double-strand breaks (DSBs) and proliferation in the human liver-derived cell line HepG2. Methods HepG2 cells were treated with CBD (5 – 50 $$\mu M$$ , 3 - 72h incubation). To investigate potential imbalances in the expression of cannabinoid receptors 1 and 2 (CB1 / CB2) within HepG2 cells, we examined their expression using Western blot analysis. We hypothesized that such an imbalance could be associated with pathogenic processes. Double-strand breaks were then detected (5 $$\mu M$$ Etoposide (ETP) served as positive control) via indirect immunofluorescence analysis using $$\gamma$$ H2AX and 53BP1 antibodies, followed by quantification of DSB foci. Results Expression of CB2 but not CB1 was downregulated by 30 % in HepG2 cells after exposure to 5 $$\mu M$$ CBD (24h incubation; $$p