Crosstalk between autophagy and apoptosis induced by camphor in Schizosaccharomyces pombe

Camphor is widely used in pharmacy, the food industry, and cosmetics. In this study, we evaluate inhibitory and cytotoxic effects of camphor in the fission yeast (Schizosaccharomyces pombe), which presents a unicellular model in mechanistic toxicology and cell biology. Low-dose camphor exposure (0.4 mg/mL) activated autophagy, which was shown by GFP-Atg8 dots and transcriptional upregulation of Atg6 (Beclin-1 ortholog). Autophagy was also confirmed by using autophagy-deficient cells, which showed reduction in GFP-Atg8 dot formation. However, high-dose camphor exposure (0.8 mg/mL) caused dramatic cell death ratios, demonstrated by spot and colony-forming assays, even in autophagy-deficient cells.