Dipropyl phthalate (DPRP), a plasticizer commonly utilized in the plastics industry, has been identified in food and the environment and has the potential to present a hazard to human health and the environment. In this study, the first comprehensive evaluation of DPRP-induced craniofacial chondrogenic defects was conducted using a zebrafish model. Zebrafish embryos were exposed to 1, 2, and 4 mg/L DPRP from 6 to 96 h post-fertilization. At 80 hpf, it was observed that exposure to DPRP resulted in craniofacial developmental malformations, which were mainly characterized by the shortening of the mandibular pharyngeal arches and the inability of the accompanying artery to elongate forward. The resulting phenotype was similar to that of micrognathia syndrome. Transcriptome sequencing and molecular docking analyses revealed that DPRP down-regulated chondrocyte-related genes and induced activation of the FoxO signaling pathway, which in turn interfered with cell proliferation and apoptosis. In this process, DPRP induced elevated levels of oxidative stress in the craniofacial pharyngeal arch while promoting inflammatory responses. This ultimately led to craniofacial chondrogenic malformations in zebrafish. The present study demonstrates that DPRP induces developmental toxicity of zebrafish craniofacial cartilage, which may have adverse effects on other aquatic organisms and humans.
Xuejun Wang,Si Shen,Hao Wu,Haixia Wang,Lvjing Wang,Zhenmei Lu
Dipropyl phthalate (DPrP) coexists with cadmium as cocontaminants in environmental media. A coculture system including the DPrP-degrading bacteriumGlutamicibacter nicotianaeZM05 and the nondegrading bacteriumAcinetobacter tandoiiZM06 was artificially established to degrade DPrP under Cd(II) stress. Strain ZM06 relieved the pressure of cadmium on strain ZM05 and accelerated DPrP degradation in the following three ways: first, strain ZM06 adsorbed Cd(II) on the cell surface (as observed by scanning electron microscopy) to decrease the concentration of Cd(II) in the coculture system; second, the downstream metabolites of ZM05 were utilized by strain ZM06 to reduce metabolite inhibition; and third, strain ZM06 supplied amino acids and fatty acids to strain ZM05 to relieve stress during DPrP degradation, which was demonstrated by comparative transcriptomic analysis. This study provides an elementary understanding of how microbial consortia improve the degradation efficiency of organic pollutants under heavy metals contamination.Keywords:metatranscriptomics;Glutamicibacter nicotianaeZM05;Acinetobacter tandoiiZM06;cooperation;DPrP biodegradation;cadmium pressure