Pisoni M, Cogotzi L, Frigeri A, Corsi I, Bonacci S, Iacocca A, Lancini L, Mastrototaro F, Focardi S, Svelto M
Department of General and Environmental Physiology, University of Bari, Via Amendola, 165/A, Bari 70125, Italy.
Environ Res. 2004 Oct;96(2):163-75. doi: 10.1016/j.envres.2004.02.011.
The aim of this study was to investigate the impact of environmental pollution at different stations along the Taranto coastline (Ionian Sea, Puglia, Italy) using several biomarkers of exposure and the effect on mussels, Mytilus galloprovincialis, collected in October 2001 and October 2002. Five sampling sites were compared with a "cleaner" reference site in the Aeronautics Area. In this study we also investigated the differences between adduct levels in gills and digestive gland. This Taranto area is the most significant industrial settlement on the Ionian Sea known to be contaminated by polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls, heavy metals, etc. Exposure to PAHs was evaluated by measuring DNA adduct levels and benzo(a)pyrene monooxygenase activity (B(a)PMO); DNA adducts were analyzed by 32P-postlabeling with nuclease P1 enhancement in both gills and digestive glands to evaluate differences between DNA adduct levels in the two tissues. B(a)PMO was assayed in the microsomal fraction of the digestive glands as a result of the high expression of P450-metabolizing enzymes in this tissue. Lysosomal membrane stability, a potential biomarker of anthropogenic stress, was also evaluated in the digestive glands of mussels, by measuring the latent activity of beta-N-acetylhexosaminidase. Induction of DNA adducts was evident in both tissues, although the results revealed large tissue differences in DNA adduct formation. In fact, gills showed higher DNA adduct levels than did digestive gland. No significant differences were found in DNA adduct levels over time, with both tissues providing similar results in both years. DNA adduct levels were correlated with B(a)PMO activity in digestive gland in both years (r = 0.60 in 2001; r = 0.73 in 2002). Increases were observed in B(a)PMO activity and DNA adduct levels at different stations; no statistical difference was observed in B(a)PMO activity over the two monitoring campaigns. The membrane labilization period in mussels from some stations was decreased in both years. No statistical differences were established in the membrane labilization times from 2001 to 2002. Our results suggest the existence of different sources and amounts of environmental contaminants at the stations investigated. The formation of DNA adducts confirms the existence of activation pathways in mussels and shows the importance of DNA adduct analysis in the gill tissue in addition to the more commonly used digestive gland; these results confirm the utility of lysosomal membrane stability as a biomarker of general stress. Overall, the integrated use of biomarkers of exposure and the effects of environmental contaminants on living marine organisms may help to better interpret the impact of pollutants in a marine coastal environment.
本研究旨在利用多种暴露生物标志物，调查意大利普利亚大区伊奥尼亚海沿岸塔兰托不同站点的环境污染情况，以及对2001年10月和2002年10月采集的加利福尼亚贻贝（Mytilus galloprovincialis）的影响。将五个采样点与航空区域内一个“更清洁”的参考站点进行了比较。在本研究中，我们还调查了鳃和消化腺中加合物水平的差异。塔兰托地区是伊奥尼亚海最重要的工业聚居地，已知受到多环芳烃（PAHs）、多氯联苯、重金属等污染。通过测量DNA加合物水平和苯并(a)芘单加氧酶活性（B(a)PMO）来评估PAHs暴露情况；采用32P后标记及核酸酶P1增强法分析鳃和消化腺中的DNA加合物，以评估两个组织中DNA加合物水平的差异。由于该组织中P450代谢酶的高表达，在消化腺的微粒体部分检测B(a)PMO。还通过测量β-N-乙酰己糖胺酶的潜在活性，评估了贻贝消化腺中溶酶体膜稳定性这一潜在的人为应激生物标志物。两个组织中均明显出现了DNA加合物的诱导现象，尽管结果显示DNA加合物形成存在较大的组织差异。事实上，鳃中的DNA加合物水平高于消化腺。随着时间推移，DNA加合物水平未发现显著差异，两个组织在这两年中均给出了相似的结果。两年中，消化腺中的DNA加合物水平均与B(a)PMO活性相关（2001年r = 0.60；2002年r = 0.73）。不同站点的B(a)PMO活性和DNA加合物水平均有所增加；两次监测活动中B(a)PMO活性未观察到统计学差异。两年中，部分站点贻贝的膜不稳定期均有所缩短。2001年至2002年，膜不稳定时间未发现统计学差异。我们的结果表明，在所调查的站点存在不同来源和数量的环境污染物。DNA加合物的形成证实了贻贝中存在活化途径，并且表明除了更常用的消化腺外，鳃组织中DNA加合物分析也很重要；这些结果证实了溶酶体膜稳定性作为一般应激生物标志物的实用性。总体而言，综合使用暴露生物标志物以及环境污染物对海洋生物的影响，可能有助于更好地解释污染物对海洋沿岸环境的影响。
