Effects of ammonia exposure on apoptosis, oxidative stress and immune response in pufferfish (Takifugu obscurus).
Ammonia is one of major environmental pollutants in the freshwater aquatic system that affects the survival and growth of organisms. In the present study, we investigated the effects of ammonia exposure on apoptosis, oxidative stress and immune response in pufferfish (Takifugu obscurus). Fish were exposed to various concentrations of ammonia (0, 1.43, 3.57, 7.14mM) for 72h. The date showed that ammonia exposure could induce intracellular reactive oxygen species (ROS), interrupt intracellular Ca(2+) (cf-Ca(2+)) homeostasis, and subsequently lead to DNA damage and cell apoptosis. To test the apoptotic pathway, the expression patterns of some key apoptotic related genes including P53, Bax Bcl2, Caspase 9, Caspase 8 and Caspase 3 in the liver were examined. The results showed that ammonia stress could change these genes transcription, associated with increasing of cell apoptosis, suggesting that the P53-Bax-Bcl2 pathway and caspase-dependent apoptotic pathway could be involved in cell apoptosis induced by ammonia stress. In addition, ammonia stress could induced up-regulation of inflammatory cytokines (BAFF, TNF-α, IL-6 and IL-12) transcription, indicating that innate immune system play important roles in ammonia-induced toxicity in fish. Furthermore, the gene expressions of antioxidant enzymes (Mn-SOD, CAT, GPx, and GR) and heat shock proteins (HSP90 and HSP70) in the liver were induced by ammonia stress, suggesting that antioxidant system and heat shock proteins tried to protect cells from oxidative stress and apoptosis induced by ammonia stress. Our results will be helpful to understand the mechanism of aquatic toxicology induced by ammonia in fish.
Key Laboratory of Ecology and Environmental Science of Guangdong Higher Education Institutes, Guangdong Provincial Key Laboratory for Healthy and Safe Aquaculture, School of Life Science, South China Normal University, Guangzhou 510631, PR China.
Chang-Hong
CH
Cheng
Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, PR China.
Fang-Fang
FF
Yang
Key Laboratory of Ecology and Environmental Science of Guangdong Higher Education Institutes, Guangdong Provincial Key Laboratory for Healthy and Safe Aquaculture, School of Life Science, South China Normal University, Guangzhou 510631, PR China.
Ren-Zhi
RZ
Ling
Key Laboratory of Ecology and Environmental Science of Guangdong Higher Education Institutes, Guangdong Provincial Key Laboratory for Healthy and Safe Aquaculture, School of Life Science, South China Normal University, Guangzhou 510631, PR China.
Shao-An
SA
Liao
Key Laboratory of Ecology and Environmental Science of Guangdong Higher Education Institutes, Guangdong Provincial Key Laboratory for Healthy and Safe Aquaculture, School of Life Science, South China Normal University, Guangzhou 510631, PR China.
Yu-Tao
YT
Miao
Key Laboratory of Ecology and Environmental Science of Guangdong Higher Education Institutes, Guangdong Provincial Key Laboratory for Healthy and Safe Aquaculture, School of Life Science, South China Normal University, Guangzhou 510631, PR China. Electronic address: chaoxia_ye@yahoo.com.cn.
Chao-Xia
CX
Ye
Key Laboratory of Ecology and Environmental Science of Guangdong Higher Education Institutes, Guangdong Provincial Key Laboratory for Healthy and Safe Aquaculture, School of Life Science, South China Normal University, Guangzhou 510631, PR China. Electronic address: wanganl@scnu.edu.cn.
An-Li
AL
Wang
D000641:Ammonia / Q000633:toxicity*; D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D004249:DNA Damage / Q000187:drug effects; D029941:Fish Proteins / Q000235:genetics; D005786:Gene Expression Regulation / Q000187:drug effects; D007107:Immune System / Q000187:drug effects*; D008099:Liver / Q000187:drug effects; D018384:Oxidative Stress / Q000187:drug effects*; D015398:Signal Transduction / Q000187:drug effects; D023741:Takifugu / Q000502:physiology*; D014874:Water Pollutants, Chemical / Q000633:toxicity
D029941:Fish Proteins; D014874:Water Pollutants, Chemical; D000641:Ammonia
Ammonia stress; Apoptosis; Immune response; Oxidative stress; Takifugu obscurus