5-Hydroxymethylfurfural mediated developmental toxicity in Drosophila melanogaster.

5-hydroxymethylfurfural is a common byproduct in food. However, its effect on growth and development remains incompletely understood. This study investigated the developmental toxicity of 5-HMF to Drosophila larvae. The growth and development of Drosophila melanogaster fed with 5-50 mM 5-HMF was monitored, and its possible mechanism was explored. It was found that 5-HMF prolonged the developmental cycle of Drosophila melanogaster (25 mM and 50 mM). After 5-HMF intake, the level of reactive oxygen species in the third instar larvae increased by 1.23-1.40 fold, which increased the level of malondialdehyde and caused changes in antioxidant enzymes. Moreover, the nuclear factor erythroid-2 related factor 2 antioxidant signaling pathway and the expression of heat shock protein genes were affected. At the same time, 5-HMF disrupted the glucose and lipid metabolism in the third instar larvae, influencing the expression level of key genes in the insulin signal pathway. Furthermore, 5-HMF led to intestinal oxidative stress, and up-regulated the expression of the pro-apoptotic gene, consequently impacting intestinal health. In short, 5-HMF causes oxidative stress, disturbs glucose and lipid metabolism and induces intestinal damage, damaging related signaling pathways, and ultimately affecting the development of Drosophila melanogaster.

Reproductive toxicity of polystyrene nanoplastics in Drosophila melanogaster under multi-generational exposure.

Micro-nanoplastics have become a new type of pollutant worldwide and have attracted widespread attention for their potential toxicity. However, the toxicity of polystyrene nanoplastics (PS-NPs) under continuous exposure of multi-generations is still unclear. In the present study, Drosophila melanogaster was selected as an in vivo biological model to investigate the reproductive toxicity and underlying mechanism induced by PS-NPs (100 nm; 1, 10, 50, and 100 mg L-1) after continuous exposure of five generations. The results showed that PS-NPs accumulated in the crop, gut and ovaries after 5 d of exposure. It was also observed that the number of egg production and eclosion rate decreased significantly (P < 0.05) accompanied by delayed development during continuous exposure PS-NPs of multi-generations. Further analysis revealed that the degree of apoptosis and necrosis of oocytes in the F5 generation increased with the increasing exposure dose. To elucidate the underlying toxicity mechanism mediated by PS-NPs, transcriptomic analysis was performed on the ovaries of the F5 generation. The results showed that there were 102 and 208 differentially expressed genes (DEGs) in the 1 mg L-1 and 100 mg L-1 PS-NPs treatment groups, respectively, compared with the control group. The transcriptome analysis further detected the KEGG pathway with significant enrichment of DEGs, revealing obvious reproductive toxicity at the molecular level. In conclusion, this research not only highlighted the negative physiological effects of multi-generational exposure to PS-NPs on Drosophila melanogaster, but also explored potential mechanisms by transcriptomic analysis to better understand reproductive toxicity induced by multi-generational exposure.