Di-(2-ethylhexyl) phthalate (DEHP)-induced testicular toxicity through Nrf2-mediated Notch1 signaling pathway in Sprague-Dawley rats

Environ Toxicol. 2018 Jul;33(7):720-728. doi: 10.1002/tox.22559. Epub 2018 Apr 16.

Abstract

Di-(2-ethylhexyl) phthalate (DEHP) is an environmental endocrine disruptor widely used in China that is harmful to the male reproductive system. Many studies have shown that DEHP causes testicular toxicity through oxidative stress, but the specific mechanism is unknown. Because the Notch pathway is a key mechanism for regulating cell growth and proliferation, we investigated whether Notch is involved in DEHP-induced testicular toxicity and whether vitamins E and C could rescue testicular impairment in Sprague-Dawley (SD) rats. Compared with the control group, we found that DEHP exposure induced testicular toxicity through oxidative stress injury, and it decreased the testosterone level (P < .01) and upregulated nuclear factor-erythroid 2 related factor (Nrf2) expression (P < .01). Therefore, because oxidative stress might be the initiating factor of DEHP-induced testicular toxicity, treatment with the antioxidant vitamins E and C activated the Notch1 signaling pathway in the testis and in Leydig cells. Treatment with vitamins E and C normalized the oxidative stress state after DEHP exposure and restored testicular development to be similar to the control group. In summary, antioxidant vitamins E and C may be used to treat DEHP-induced testicular toxicity.

Keywords: DEHP; Leydig cell; oxidative stress; testis.

MeSH terms

  • Animals
  • Ascorbic Acid / pharmacology
  • Cell Survival / drug effects
  • Cells, Cultured
  • Diethylhexyl Phthalate / toxicity*
  • Down-Regulation / drug effects
  • Leydig Cells / cytology
  • Leydig Cells / drug effects
  • Leydig Cells / metabolism
  • Male
  • Microscopy, Fluorescence
  • NF-E2-Related Factor 2 / metabolism*
  • Oxidative Stress / drug effects
  • Plasticizers / toxicity*
  • Rats
  • Rats, Sprague-Dawley
  • Reactive Oxygen Species / metabolism
  • Receptor, Notch1 / metabolism
  • Signal Transduction / drug effects*
  • Testis / drug effects
  • Testis / metabolism
  • Testis / pathology
  • Testosterone / metabolism
  • Vitamin E / pharmacology

Substances

  • NF-E2-Related Factor 2
  • Plasticizers
  • Reactive Oxygen Species
  • Receptor, Notch1
  • Vitamin E
  • Testosterone
  • Diethylhexyl Phthalate
  • Ascorbic Acid