Cadmium induces hydrogen peroxide production and initiates hydrogen peroxide-dependent apoptosis in the gill of freshwater crab, Sinopotamon henanense.
Cadmium (Cd) is a well-known toxic heavy metal that accumulates in the aquatic environment. Cd has been reported to induce oxidative damage and apoptosis. We investigated the regulation mechanism of hydrogen peroxide (H(2)O(2)) on Cd-induced apoptosis. We show that in the gills of the freshwater crab Sinopotamon henanense Cd induced apoptosis, in a time- and concentration-dependent manner, as confirmed by DNA fragmentation analysis and transmission electron microscopy. Additionally, Cd caused production of H(2)O(2) after 2 h of treatment at 58 mg L(-1) Cd, and significantly increased the caspase-3/8/9 activity in crabs relative to the control group. Pre-treatment with the scavenger for H(2)O(2), dimethylthiourea (DMTU) and antioxidant, N-acetyl cysteine (NAC), effectively inhibited the activities of caspase-3 and caspase-9, eventually blocked Cd-induced DNA fragmentation and the appearance of markers for apoptotic cell death. These results suggest that Cd might induce intracellular H(2)O(2) generation to trigger the crab apoptotic processes by regulating the activities of caspase enzymes.
School of Life Science, Shanxi University, Taiyuan 030006, China.
Jinxiang
J
Wang
Qian
Q
Wang
Jiarui
J
Li
Qingqing
Q
Shen
Fei
F
Wang
Lan
L
Wang
D000111:Acetylcysteine / Q000494:pharmacology; D000818:Animals; D017209:Apoptosis; D015415:Biomarkers / Q000378:metabolism; D003386:Brachyura / Q000033:anatomy & histology / Q000187:drug effects* / Q000378:metabolism; D002104:Cadmium / Q000633:toxicity*; D053148:Caspase 3 / Q000378:metabolism; D053453:Caspase 9 / Q000378:metabolism; D061945:Caspase Inhibitors / Q000494:pharmacology; D053938:DNA Fragmentation; D004305:Dose-Response Relationship, Drug; D004789:Enzyme Activation; D005880:Gills / Q000187:drug effects* / Q000378:metabolism / Q000648:ultrastructure; D006861:Hydrogen Peroxide / Q000378:metabolism*; D008297:Male; D046529:Microscopy, Electron, Transmission; D017382:Reactive Oxygen Species / Q000378:metabolism; D013890:Thiourea / Q000031:analogs & derivatives / Q000494:pharmacology; D013997:Time Factors; D018675:Toxicity Tests / Q000379:methods
D015415:Biomarkers; D061945:Caspase Inhibitors; D017382:Reactive Oxygen Species; D002104:Cadmium; C038983:1,3-dimethylthiourea; D006861:Hydrogen Peroxide; D053148:Caspase 3; D053453:Caspase 9; D013890:Thiourea; D000111:Acetylcysteine