Department of Chemical, Biological, Pharmaceutical, and Environmental Sciences, University of Messina, 98166, Messina, Italy.
Department of Human Pathology in Adult and Developmental Age, University of Messina, 98125, Messina, Italy.
J Trace Elem Med Biol. 2021 Dec;68:126870. doi: 10.1016/j.jtemb.2021.126870. Epub 2021 Sep 28.
Trace elements present in sessile molluscs, are important because they are used in human consumption and it has significantly increased in recent years. While their filtering of the water can lead to their build-up of organic and inorganic materials that can be sampled and analyzed, this can also lead to bioaccumulation of harmful substances, such as essential and non-essential elements, that can harm the human health if in taken in high concentrations or for a long period of time.
In the present study, the trace metal content (Al, Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn) of two sessile crustaceans, 20 Mytilus galloprovincialis (mussel) and 20 Tapes decussatus (clam) in Faro and Ganzirri Lakes (Messina, Sicily, Italy) were analyzed. Haemolymph samples were taken on both molluscs in order to analyze the haemocyte population by flow cytometric analysis. Unpaired t-tests were used to determine significant differences for the essential and non-essential metallic elements concentrations in the lake waters and in the tissues of M. galloprovincialis and T. decussatus and for hemocyte populations R1 (halinocytes) and R2 (granulocytes).
The results suggested that that in Faro Lake, the tissue Al, Cr and Pb levels in M. galloprovincialis were higher than those for T. decussatus, in contrast to Mn, Fe, Ni, Cu, Zn and Cd, which were higher in T. decussatus. Unpaired t-tests showed that there were significantly higher proportions of halinocytes in M. galloprovincialis versus T. decussatus for both Faro Lake (41.8 % vs. 24.3 %; P < 0.001) and Ganzirri Lake (43.0 % vs. 22.4 %; P < 0.001). In contrast, while there were significantly higher proportions of granulocytes in Faro Lake (21.2 % vs. 9.1 %; P < 0.001), this difference was not seen for the granulocytes of M. galloprovincialis versus T. decussatus in Ganzirri Lake (9.6 % vs. 13.0 %).
This study shows that M. galloprovincialis and T. decussatus can indeed bioaccumulate some of these metal, such that activation of the immune responses is specific to certain cell types. Future research must focus on the balance of trace elements in the consumption of these shellfish, and analyzes with more sophisticated tools can be used to diagnose the increased concentration of trace elements and the quantification of trace metals from shellfish to clams.
固着蛤类中存在的微量元素很重要，因为它们被人类食用，而且近年来摄入量显著增加。虽然它们过滤水中的有机和无机物质可以进行采样和分析，但这也会导致有害物质的生物积累，如必需和非必需元素，如果长期摄入高浓度的这些元素，会对人体健康造成危害。
在本研究中，分析了来自法罗湖和甘齐里里湖（意大利西西里墨西拿）的 20 只贻贝（Mytilus galloprovincialis）和 20 只帘蛤（Tapes decussatus）中 2 种固着甲壳类动物的痕量金属含量（Al、Cd、Cr、Cu、Fe、Mn、Ni、Pb 和 Zn）。为了分析血细胞群体，从两种贝类中抽取血淋巴样本，采用流式细胞术分析。采用独立样本 t 检验来确定湖泊水中以及 M. galloprovincialis 和 T. decussatus 组织中必需和非必需金属元素浓度以及血细胞群体 R1（halinocytes）和 R2（granulocytes）的显著差异。
结果表明，在法罗湖中，M. galloprovincialis 的组织 Al、Cr 和 Pb 水平高于 T. decussatus，而 Mn、Fe、Ni、Cu、Zn 和 Cd 水平则高于 T. decussatus。独立样本 t 检验显示，在法罗湖和甘齐里里湖中，M. galloprovincialis 的 halinocytes 比例显著高于 T. decussatus（分别为 41.8%对 24.3%；P<0.001）和（分别为 43.0%对 22.4%；P<0.001）。相比之下，在法罗湖中，granulocytes 的比例显著高于 T. decussatus（分别为 21.2%对 9.1%；P<0.001），而在甘齐里里湖中，M. galloprovincialis 的 granulocytes 比例与 T. decussatus 之间没有显著差异（分别为 9.6%对 13.0%）。
本研究表明，M. galloprovincialis 和 T. decussatus 确实可以生物积累某些金属，从而使免疫反应的激活具有特定的细胞类型。未来的研究必须集中在这些贝类食用中的微量元素平衡上，并且可以使用更复杂的工具进行分析，以诊断痕量元素的浓度增加和贝类到帘蛤的痕量金属的定量。
