Transgenerational response of glucose metabolism in Caenorhabditis elegans exposed to 6-PPD quinone.

In Caenorhabditis elegans, 6-PPD quinine (6-PPDQ) could cause several aspects of toxicity together with alteration in glucose metabolism. However, transgenerational alteration in glucose metabolism remains still unknown after 6-PPDQ exposure. In the current study, we further observed transgenerational increase in glucose content induced by 6-PPDQ (1-10 μg/L). After 1-10 μg/L 6-PPDQ exposure, although expressions of genes controlling gluconeogenesis were not changed in the offspring, expressions of hxk-1, hxk-3, pyk-1, and pyk-2 controlling glycolysis could be decreased in the offspring. Meanwhile, transgenerational decrease in expressions of daf-16 encoding FOXO transcriptional factor and aak-2 encoding AMPK was detected in the offspring of 6-PPDQ (1-10 μg/L) exposed nematodes. RNAi of daf-16 and aak-2 led to more severe transgenerational increase in glucose content and reduction in expressions of hxk-1 and hxk-3 induced by 6-PPDQ. Moreover, RNAi of daf-16, aak-2, hxk-1, hxk-3, pyk-1, and pyk-2 caused susceptibility to transgenerational 6-PPDQ toxicity on locomotion and reproduction. Additionally, 6-PPDQ induced activation of SOD-3 and HSP-6 reflecting anti-oxidation and mitochondrial UPR responses could be inhibited by RNAi of daf-16, aak-2, hxk-1, hxk-3, pyk-1, and pyk-2. Therefore, exposure to 6-PPDQ potentially resulted in transgenerational alteration in glucose metabolism, which provided the possible link to induction of transgenerational 6-PPDQ toxicity in organisms.