NAP Family CG5017 Chaperone Pleiotropically Regulates Human AHR Target Genes Expression in Drosophila Testis

Combining in vivo pathohistological and redox status analysis with in silico toxicogenomic study to explore the phthalates and bisphenol A mixture-induced testicular toxicity

The aim of this study was to: (i) determine and compare the capacity of bis (2 -ethylhexyl) phthalate (DEHP), dibutyl phthalate (DBP), bisphenol A (BPA), and their mixture to produce testicular toxicity after the subacute exposure; (ii) explore the mechanisms behind the observed changes using in silico toxicogenomic approach. Male rats were randomly split into groups (n = 6): (1) Control (corn oil); (2) DEHP (50 mg/kg b.w./day); (3) DBP (50 mg/kg b.w./day); (4) BPA (25 mg/kg b.w./day); and (5) MIX (50 mg/kg b.w./day DEHP + 50 mg/kg b.w/day DBP + 25 mg/kg b.w./day BPA). Animals were sacrificed after 28 days of oral exposure, testes were extracted and prepared for histological assessments under the light microscope (haematoxylin and eosin staining) and redox status analysis. The Comparative Toxicogenomics Database (CTD; http://CTD.mdibl.org), Cytoscape software (https://cytoscape.org) and ToppGene Suite (https://toppgene.cchmc.org) were used for data-mining. Present pathohistological study has demonstrated more pronounced testicular toxicity of the MIX group (desquamated germinal epithelium cells, enlarged cells with hyperchromatic nuclei, multinucleated cell forms and intracytoplasmic vacuoles) in comparison with the single substances, while effects on redox status parameters were either more prominent, or present only in the MIX group. In silico investigation revealed 20 genes linked to male reproductive disorders, affected by all three investigated substances. Effects on metabolism, AhR pathway, apoptosis and oxidative stress could be singled out as the most probable mechanisms involved in the subacute DEHP, DBP and BPA mixture testicular toxicity, while the effect on oxidative stress parameters was confirmed by in vivo experiment.

Aryl Hydrocarbon Receptor as a Target for Lycopene Preventing DEHP-Induced Spermatogenic Disorders

Di(2-ethylhexyl)phthalate (DEHP) is widely used as a plasticizer to improve product flexibility and workability. Lycopene (LYC) is a natural compound and has promising preventive potentials, especially antireproductive toxicity, but the specific underlying mechanism is yet to be fully defined. Our study investigated the effect of LYC on DEHP-induced spermatogenesis disorders. Male ICR mice were treated with DEHP (500 or 1000 mg/kg BW/day) and/or LYC (5 mg/kg BW/day) for 28 days. Our results indicated that LYC could relieve the DEHP-induced injury of seminiferous tubules and spermatogenic cells, swelling of endoplasmic reticulum (ER), and an increase of mitochondria. LYC prevented increased levels of nuclear damage to DNA and the deformity rate and decreased values of sperm motility, number, and density. Moreover, LYC treatment decreased DEHP-induced nuclear accumulation of aryl hydrocarbon receptor (AHR) and AHR nuclear translocator (ARNT), and the expressions of their downstream target genes such as cytochrome P450-dependent monooxygenases (CYP) 1A1, 1A2, and 1B1 were markedly reduced to normal in the LYC treatment group. Our study showed that LYC can prevent DEHP-induced spermatogenic disorders via an AHR/ARNT signaling system. This study provided new evidence of AHR as a target for LYC, which can prevent DEHP-induced toxicity.