Pubertal exposure to tebuconazole increases testosterone production via inhibiting testicular aromatase activity in rats

Chemosphere. 2019 Sep:230:519-526. doi: 10.1016/j.chemosphere.2019.05.122. Epub 2019 May 15.

Abstract

Tebuconazole is a triazole compound used agriculturally to treat plant pathogenic fungi. However, whether pubertal exposure to tebuconazole affects Leydig cell development remains unknown. Here, we exposed male Sprague-Dawley rats at 35 days of age to 0, 25, 50, or 100 mg kg-1 day-1 tebuconazole for 21 days. Tebuconazole exposure increased serum testosterone level but lowered estradiol level at a dose of 100 mg kg-1, without affecting serum luteinizing hormone and follicle-stimulating hormone concentrations. Tebuconazole up-regulated the expression of testicular Cyp11a1, Hsd11b1, and Fshr genes as well as their proteins at a dose of 100 mg kg-1. However, tebuconazole did not stimulate the proliferation of Leydig cells. Tebuconazole in vitro inhibits aromatase activity in primary rat Leydig cells with IC50 value of 40 μmol/L. In conclusion, tebuconazole exposure stimulates pubertal Leydig cell differentiation via inhibiting aromatase activity.

Keywords: Aromatase; Fungicide; Leydig cell; Rat; Tebuconazole; Testosterone.

MeSH terms

  • Aging / blood
  • Animals
  • Aromatase / metabolism*
  • Cell Differentiation / drug effects
  • Follicle Stimulating Hormone / blood
  • Fungicides, Industrial / toxicity*
  • Gene Expression / drug effects
  • Leydig Cells / drug effects
  • Leydig Cells / enzymology
  • Luteinizing Hormone / blood
  • Male
  • Rats
  • Rats, Sprague-Dawley
  • Testis / drug effects*
  • Testis / enzymology
  • Testis / growth & development
  • Testosterone / blood*
  • Triazoles / toxicity*
  • Up-Regulation

Substances

  • Fungicides, Industrial
  • Triazoles
  • Testosterone
  • tebuconazole
  • Luteinizing Hormone
  • Follicle Stimulating Hormone
  • Aromatase