Effects of MCLR exposure on sex hormone synthesis and reproduction-related genes expression of testis in male Rana nigromaculata. (May 2018)

• Record Type: Journal Article
• Authors: Jia, Xiuying; Liu, Zhengquan; Lu, Xiangjun; Tang, Juan; Wu, Yingzhu; Du, Qiongxia; He, Jianbo; Zhang, Xinyun; Jiang, Jinxiao; Liu, Wenli; Zheng, Yuqing; Ding, Ying; Zhu, Weiqin; Zhang, Hangjun
• Is Part Of: Environmental pollution. Volume 236(2018)
• Page Start: 12
• Page End: 20
• Publication Date: 2018-05
• Subjects: Microcystin-LR -- Reproductive toxicity -- Steroidogenesis -- Sex hormone receptors -- Rana nigromaculata; Pollution -- Periodicals; Pollution -- Environmental aspects -- Periodicals; Environmental Pollution -- Periodicals; Pollution -- Périodiques; Pollution -- Aspect de l'environnement -- Périodiques; Pollution -- Effets physiologiques -- Périodiques; Pollution; Pollution -- Environmental aspects; Periodicals; Electronic journals; 363.73
• DOI: 10.1016/j.envpol.2018.01.057
• Languages: English
• ISSNs: 0269-7491

Abstract

Abstract: Microcystin-leucine-arginine (MCLR) is the most popular and toxic variant among microcystins, which can cause severe reproductive toxicity to animals. However, the mechanisms of reproductive toxicity induced by MCLR in amphibians are still not entirely clear. In the current study, toxicity mechanisms of MCLR on the reproductive system of male Rana nigromaculata followed by low concentration (0, 0.1, 1, and 10 μg/L) and short-term (0, 7, and 14 days) MCLR exposure were shown. It was observed that MCLR could be bioaccumulated in the testes of male frogs, and the theoretical bioaccumulation factor values were 0.24 and 0.19 exposed to 1 μg/L and 10 μg/L MCLR for 14 days, respectively. MCLR exposure significantly decreased testosterone (T) concentrations and increased estradiol (E2) concentrations exposed to 1 and 10 μg/L MCLR for 14 days. The mRNA levels of HSD17B3 were downregulated, and HSD17B1 and CYP19A1 mRNA expression levels were upregulated, respectively. Only 10 μg/L MCLR group showed significant induction of follicle-stimulating hormone (FSH) levels and cyclic adenosine monophosphate (cAMP) content. Moreover, AR and ESR1 mRNA expression levels were significantly upregulated exposed to 1 and 10 μg/L MCLR for 14 days, respectively. Our results suggested that low-concentration MCLR induced transcription changes of CYP19A1, HSD17B3, and HSD17B1 led to endocrine disorders, and caused interference of spermatogenesis by the decrease of T and abnormal gene expressions of AR and ESR1 in the testes of R. nigromaculata . Graphical abstract: Image 1 Highlights: MCLR can be bioaccumulated in the testis R. nigromaculata in a concentration and time dependent manner. MCLR exposure can cause endocrine disorders in R. nigromaculata. MCLR-induced abnormal gene expressions of CYP19A1, HSD17B3, and HSD17B1 mainly led to a decrease in T/E2 ratio. MCLR-induced the decrease of T, and abnormal gene expression of AR and ESR1 caused interference of spermatogenesis. Abstract : Low-concentration MCLR exposure can be bioaccumulated in the testes of R. nigromaculata, causing endocrine disorders by transcription changes of steroidogenesis enzymes, and causing interference of spermatogenesis by the decrease of T and abnormal gene expression of AR and ESR1 .MCLR exposure caused endocrine disorders and altered reproduction-related gene expression in the testes of male Rana nigromaculata .