Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5764281 | Aquatic Toxicology | 2017 | 32 Pages |
Abstract
To evaluate the adverse effects of MeHg on the rotifer Brachionus koreanus and the copepod Paracyclopina nana, we assessed the effects of MeHg toxicity on life parameters (e.g. growth retardation and fecundity), antioxidant systems, and mitogen-activated protein kinase (MAPK) signaling pathways at various concentrations (1Â ng/L, 10Â ng/L, 100Â ng/L, 500Â ng/L, and 1000Â ng/L). MeHg exposure resulted in the growth retardation with the increased ROS levels but decreased glutathione (GSH) levels in a dose-dependent manner in both B. koreanus and P. nana. Antioxidant enzymatic activities (e.g. glutathione S-transferase [GST], glutathione reductase [GR], and glutathione peroxidase [GPx]) in B. koreanus showed more positive responses compared the control but in P. nana, those antioxidant enzymatic activities showed subtle changes due to different no observed effect concentration (NOEC) values among the two species. Expression of antioxidant genes (e.g. superoxide dismutase [SOD], GSTs, glutathione peroxidase [GPx], and catalase [CAT]) also demonstrated similar effects as shown in antioxidant enzymatic activities. In B. koreanus, the level of p-ERK was decreased in the presence of 1000Â ng/L MeHg, while the levels of p-ERK and p-p38 in P. nana were reduced in the presence of 10Â ng/L MeHg. However, p-JNK levels were not altered by MeHg in B. koreanus and P. nana, compared to the corresponding controls. In summary, life parameters (e.g. reduced fecundity and survival rate) were closely associated with effects on the antioxidant system in response to MeHg. These observations provide a better understanding on the adverse effects of MeHg on in vivo life parameters and molecular defense mechanisms in B. koreanus and P. nana.
Keywords
Related Topics
Life Sciences
Agricultural and Biological Sciences
Aquatic Science
Authors
Young Hwan Lee, Duck-Hyun Kim, Hye-Min Kang, Minghua Wang, Chang-Bum Jeong, Jae-Seong Lee,