Integrated multi-omics analysis dissects di-isobutyl phthalate exposure-induced male fertility impairment

Di-isobutyl phthalate (DiBP), a member of the phthalate esters, is frequently used in manufacturing consumer and industrial products as plasticizer to improve durability and flexibility. Despite much research, little is known about the direct mechanisms by which DiBP harms the male reproductive system. In the present study, a male ICR mice model was developed to investigate the reproductive effect and mechanism of DiBP exposure, followed by transcriptomics, non-targeted metabolome, and 16S rDNA sequencing accordingly. The results showed that DiBP exposure induced male reproductive malfunction, including testis damage, spermatogenesis impairment, steroid hormone disorders, with sperm quality decline. Totally, 3 and 56 floras at the phylum and genus levels were markedly changed in the DiBP group, as indicated by 16S rDNA sequencing. Besides, untargeted metabolomics uncovered that the 23 altered metabolites were mainly altered by DiBP. Combined analysis indicated that DiBP exposure may disturb the community composition of Paramuribaculum and Alloprevotella, thus upregulated the level of Glycerol 3-phosphate (Gro3P). Transcriptome sequencing and its combined analysis with metabolomic assay were further performed to explore the molecular mechanisms underlying the metabolic perturbation. The key involved genes included Abcd2, Ogdhl, and Ppp1r3g, and the key metabolite Gro3P were further identified. Both of them were significantly associated with reproduction-related parameters. Taken together, the findings of this study provide clues for clarifying molecular mechanisms in toxicity effects induced by DiBP exposure from the perspectives of gut microbiota, transcriptome and metabolome.