Red Sea Research Center (RSRC), King Abdullah University of Science and Technology (KAUST), Thuwal 23955, Saudi Arabia.
Australian Institute of Marine Science (AIMS), Townsville 4810, Queensland, Australia; James Cook University (JCU), Townsville, Queensland 4811, Australia.
Aquat Toxicol. 2018 May;198:165-174. doi: 10.1016/j.aquatox.2018.03.008. Epub 2018 Mar 9.
Exposure to polycyclic aromatic carbons (PAHs) poses a growing risk to coral reefs due to increasing shipping and petroleum extraction in tropical waters. Damaging effects of specific PAHs can be further enhanced by the presence of ultraviolet radiation, known as phototoxicity. We tested phototoxic effects of the PAHs anthracene and phenanthrene on larvae of the scleractinian coral Acropora tenuis in the presence and absence of UVA (320-400 nm). Activity of superoxide dismutase (SOD) enzyme was reduced by anthracene while phenanthrene and UVA exposure did not have any effect. Gene expression of MnSod remained constant across all treatments. The genes Catalase, Hsp70 and Hsp90 showed increased expression levels in larvae exposed to anthracene, but not phenanthrene. Gene expression of p53 was upregulated in the presence of UVA, but downregulated when exposed to PAHs. The influence on stress-related biochemical pathways and gene expresson in A. tenuis larvae was considerably greater for anthracene than phenanthrene, and UVA-induced phototoxicity was only evident for anthracene. The combined effects of UVA and PAH exposure on larval survival and metamorphosis paralleled the sub-lethal stress responses, clearly highlighting the interaction of UVA on anthracene toxicity and ultimately the coral's development.
多环芳烃 (PAHs) 的暴露对珊瑚礁构成了越来越大的风险，这是由于热带水域的航运和石油开采增加所致。特定 PAHs 的破坏性影响可以通过紫外线辐射（称为光毒性）进一步增强。我们在存在和不存在 UVA（320-400nm）的情况下，测试了蒽和菲这两种多环芳烃对软珊瑚 Acropora tenuis 幼虫的光毒性作用。蒽降低了超氧化物歧化酶 (SOD) 酶的活性，而菲和 UVA 暴露则没有任何影响。MnSod 的基因表达在所有处理中保持不变。在暴露于蒽的幼虫中，Catalase、Hsp70 和 Hsp90 基因的表达水平增加，但在暴露于菲的幼虫中则没有。p53 基因在 UVA 存在下被上调，但在暴露于 PAHs 时被下调。蒽对 A. tenuis 幼虫的应激相关生化途径和基因表达的影响明显大于菲，而只有蒽会产生 UVA 诱导的光毒性。UVA 和 PAH 暴露对幼虫存活率和变态的综合影响与亚致死应激反应相似，这清楚地强调了 UVA 对蒽毒性的相互作用以及珊瑚的发育。
