Next Article in Journal
Human Illnesses and Animal Deaths Associated with Freshwater Harmful Algal Blooms—Kansas
Previous Article in Journal
Detection of Cyanotoxins, β-N-methylamino-L-alanine and Microcystins, from a Lake Surrounded by Cases of Amyotrophic Lateral Sclerosis
Article Menu

Export Article

Open AccessArticle
Toxins 2015, 7(2), 337-352; doi:10.3390/toxins7020337

Subacute Microcystin-LR Exposure Alters the Metabolism of Thyroid Hormones in Juvenile Zebrafish (Danio Rerio)

1,2,3
,
1,2,3,* , 1,2,3,4,* , 1,2,3
and
1
1
College of Fisheries, Huazhong Agricultural University, Wuhan 430070, China
2
Freshwater Aquaculture Collaborative Innovation Center of Hubei Province, Wuhan 430070, China
3
Key Laboratory of Freshwater Animal Breeding, Ministry of Agriculture, Wuhan 430070, China
4
Life Science College, Hunan University of Arts and Science, Changde 415000, China
*
Authors to whom correspondence should be addressed.
Academic Editor: John Berry
Received: 19 November 2014 / Revised: 14 January 2015 / Accepted: 21 January 2015 / Published: 30 January 2015
(This article belongs to the Section Marine and Freshwater Toxins)
View Full-Text   |   Download PDF [3114 KB, uploaded 2 February 2015]   |  

Abstract

Microcystin-LR (MC-LR) has been detected extensively in the aquatic environment and has the potential to disturb the thyroid endocrine system. However, limited information is available on the effects of subacute MC-LR exposure on fish thyroid hormone (TH) metabolism. In the present study, juvenile zebrafish (Danio rerio) were exposed to MC-LR at environmentally relevant concentrations (0, 1, 5, and 25 μg/L) for 28 days. Whole-body TH content and thyroid follicle histology were used as direct endpoints to assess thyroid disruption. The activities of iodothyronine deiodinases (IDs) and the transcription of selected genes associated with TH synthesis were also investigated to study the underlying mechanisms of endocrine disruption. Exposure of zebrafish to MC-LR significantly increased whole-body thyroxine (T4) content but decreased whole-body triiodothyronine (T3) content. We also observed hypertrophy and hyperplasia of the thyroid follicle epithelial cells, as well as up-regulation of corticotropin-releasing hormone (CRH), thyroid-stimulating hormone (TSH), thyroid peroxidase (TPO), and transthyretin (TTR) genes. The decreases in ID1 and ID2 activities coupled with an increase in ID3 activity were observed in MC-LR treatment groups. These results demonstrate that exposure to MC-LR at environmental concentrations results in the disturbance of TH homeostasis by disrupting the synthesis and conversion of THs. View Full-Text
Keywords: microcystin-LR; thyroid hormones; histology; gene expression; iodothyronine deiodinases; zebrafish microcystin-LR; thyroid hormones; histology; gene expression; iodothyronine deiodinases; zebrafish
Figures

Figure 1a

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. (CC BY 4.0).

Scifeed alert for new publications

Never miss any articles matching your research from any publisher
  • Get alerts for new papers matching your research
  • Find out the new papers from selected authors
  • Updated daily for 49'000+ journals and 6000+ publishers
  • Define your Scifeed now

SciFeed Share & Cite This Article

MDPI and ACS Style

Liu, Z.; Tang, R.; Li, D.; Hu, Q.; Wang, Y. Subacute Microcystin-LR Exposure Alters the Metabolism of Thyroid Hormones in Juvenile Zebrafish (Danio Rerio). Toxins 2015, 7, 337-352.

Show more citation formats Show less citations formats

Related Articles

Article Metrics

Article Access Statistics

1

Comments

[Return to top]
Toxins EISSN 2072-6651 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top