Cadmium stress induces mitochondrial damage and transgenerational inheritance in Drosophila melanogaster

Cadmium (Cd) is a common toxic heavy metal in the environment, which can exert extensive toxic effects on the reproduction, development, and aging of organisms. This study employed Drosophila melanogaster (Canton-S strain) to investigate the developmental toxicity and transgenerational genetic effects of Cd, a prevalent environmental toxic heavy metal. The study showed that Cd exposure caused a significant reduction in F₀ citrate synthase activity, an effect that persisted for two generations specifically in female treatment groups. Cd exposure was associated with transcriptional and enzymatic alterations suggestive of mitochondrial damage characterized by reduced functional activity, imbalance of mitochondrial fission and fusion dynamics, and abnormal autophagy levels, specifically characterized by excessive mitochondrial fission and inhibited mitochondrial fusion. These alterations could be inherited maternally by female offspring not directly exposed to Cd. These results confirm that Cd-induced developmental toxicity exerts intergenerational and transgenerational effects, emphasizing the importance of considering intergenerational effects and transgenerational inheritance in the assessment of Cd toxicity and environmental risks.