Biological Trace Element Research

, Volume 185, Issue 1, pp 185–196 | Cite as

Mercuric Chloride Induced Ovarian Oxidative Stress by Suppressing Nrf2-Keap1 Signal Pathway and its Downstream Genes in Laying Hens

  • Yan Ma
  • Mingkun Zhu
  • Liping Miao
  • Xiaoyun Zhang
  • Xinyang Dong
  • Xiaoting ZouEmail author


The present study evaluated the effects of mercury chloride (HgCl2) on follicular atresia rate, sex hormone secretion, and ovarian oxidative stress in laying hens. Antioxidant enzyme genes and the nuclear factor erythroid 2-related factor 2 (Nrf2)-Kelch-like ECH-associated protein 1 (Keap1) signal pathway were further studied to uncover the molecular mechanism. A total of 768 40-week-old Hy-Line Brown laying hens were randomly allocated to four treatments with eight pens per treatment and 24 hens of each pen. The birds were fed with four experimental diets containing graded levels of mercury (Hg) at 0.280, 3.325, 9.415, and 27.240 mg/kg, respectively. Results revealed that a positive relationship occurred between the accumulation of Hg in ovary and follicular atresia rate. Progesterone (P4) level significantly decreased in all Hg-treatment groups (P < 0.05), and follicle-stimulating hormone (FSH) and luteinizing hormone (LH) levels were the lowest in the 27.240-mg/kg Hg group. Besides, the activities of catalase (CAT), superoxidative dismutase (SOD), glutathione reductase (GR), and glutathione (GSH) content were significantly decreased in all Hg-treatment groups (P < 0.05). Glutathione peroxidase (GSH-Px) activity significantly decreased, while malondialdehyde (MDA) content sharply increased in the 27.240-mg/kg Hg group (P < 0.05). In addition, there were positive relationships between antioxidant enzyme activities and antioxidant gene expressions or between antioxidant gene expressions and Nrf2 mRNA expression, while negative correlations occurred between Nrf2 and Keap1 at transcription and protein levels. It could be concluded that Hg induced ovarian function disorders and ovarian oxidative stress by means of impairing the Nrf2-Keap1 signal pathway in laying hens.


Laying hens Mercury Nrf2-Keap1 Ovary Oxidative stress 



This research was supported by the Modern Argo-industry Technology Research System of China (CARS-40-K10) and the National Key Technology R&D Program (204BAD13B04).

Compliance with Ethical Standards

The experiment was carried out according to the Guiding Principles in the Use of Animals in Toxicology, adopted by the Chinese Society of Toxicology. The animal procedures were approved by the Animal Ethics Committee of Zhejiang University (Hangzhou, China).

Conflict of Interest

The authors declare that they have no conflict of interest.

Supplementary material

12011_2018_1244_MOESM1_ESM.docx (31 kb)
ESM 1 (DOCX 31 kb)


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Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2018

Authors and Affiliations

  • Yan Ma
    • 1
  • Mingkun Zhu
    • 1
  • Liping Miao
    • 1
  • Xiaoyun Zhang
    • 1
  • Xinyang Dong
    • 1
  • Xiaoting Zou
    • 1
    Email author
  1. 1.Key Laboratory of Animal Feed and Nutrition of Zhejiang Province, Feed Science Institute, College of Animal ScienceZhejiang UniversityHangzhouChina

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