Chlorocholine chloride induced testosterone secretion inhibition mediated by endoplasmic reticulum stress in primary rat Leydig cells

Chlorocholine chloride (CCC) is well acknowledged as a plant growth regulator and may be considered as a potential environmental endocrine disrupting chemical. In our previous studies, it was found that CCC exposure at a pubertal stage reduced the serum and testicular levels of testosterone, decreased the sperm motility and delayed the puberty onset. However, the molecular mechanisms of CCC-induced testosterone secretion disorders remain unclear. In this study, we found that CCC exposure above 20 mg/mL inhibited the secretion of testosterone in Sprague-Dawley rats Leydig cells. Proteomic and pathway enrichment analysis indicated that CCC might induce endoplasmic reticulum (ER) stress. Western blot detection showed CCC exposure at 100, 200 mg/mL increased the protein level of glucose regulated protein 78 (GPR78), C/EBP-homologous protein (CHOP), the ubiquitin-conjugating enzyme E2 D1 (UBE2D1) and the ring finger protein (RNF185) in the Leydig cells. The Leydig cells treated with 4 phenyl butyric acid (4-PBA), an ER stress inhibitor, rescued the testosterone secretion disorders and alleviated CCC-induced increase in the ER stress related protein levels at 200 mg/mL CCC treatment. Overall, CCC in vitro exposure might disturb testosterone production of Leydig cells and endoplasmic reticulum stress was involved in it. (c) 2021 Elsevier B.V. All rights reserved.

Automated summary

Chlorocholine chloride (CCC) is a plant growth regulator with potential as an environmental endocrine disrupting chemical. In this study, it was found that CCC exposure inhibited testosterone secretion in Sprague-Dawley rats Leydig cells, possibly through inducing endoplasmic reticulum (ER) stress. The increase in ER stress-related protein levels caused by CCC exposure could be alleviated by treatment with an ER stress inhibitor, which rescued the testosterone secretion disorders.