Combined Effects of Dibutyl Phthalate (DBP) and Benzo(a)Pyrene on Fertility in Male Rats

Yujing Huang, Ji’an Chen, Weiqun Shu

Department of Environmental Hygiene, College of Preventive Medicine, Third Military Medical University, Chongqing, China.

DOI: 10.4236/gep.2014.22023                

Abstract

Our previous studies revealed the polycyclic aromatic hydrocarbon and phthalic acid esters were the major organic pollutants in the Jialing River and Yangtze River in the Three Gorges area, and they might cause the toxicity in male fertility when combined. Thus we used di-n-butyl phthalate (DBP) and Benzo(a)pyrene (Bap) as their representatives respectively to explore their effects on the spermatogenesis in male rats. Male Sprague Dawley rats were randomly divided into 4 groups and respectively exposed to corn oil, Bap (5 mg/kg/d), DBP (250 mg/kg/d), and combined doses of Bap (5 mg/kg/d) and DBP (250 mg/kg/d) for 90 days. We observed a significant increase in the stillbirth rate after Bap and combined treatments, while the mean area of seminiferous tubules was reduced after Bap, DBP and combined treatments. Bap and combined treatment had a sup- pressing effect on meiosis in germ cells, which reduced the haploid contents and the ratio between haploid and diploid but increased the tetraploid and diploid contents and the ratio between hap- loid and tetraploid. These effects were more obvious in the combined group. Furthermore, the ex- pression of a number of proteins was changed, of which was associated with the oxidative stress and cAMP/PKA signaling pathway. Our results suggest that Bap has significant toxic effects on male fertility, while the combined treatment of Bap and DBP has more toxic effects.

Keywords

Di-n-Butyl Phthalate; Benzo(a)Pyrene; Male Reproductive; Protein Expression; Tubules Structure; Spermatogenesis

Conflicts of Interest

The authors declare no conflicts of interest.

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