Mercury-Pollution Induction of Intracellular Lipid Accumulation and Lysosomal Compartment Amplification in the Benthic Foraminifer Ammonia parkinsoniana

• Published in: PloS one 2016-09, Vol.11 (9), p.e0162401-e0162401
• Main Authors: Frontalini, Fabrizio, Curzi, Davide, Cesarini, Erica, Canonico, Barbara, Giordano, Francesco M, De Matteis, Rita, Bernhard, Joan M, Pieretti, Nadia, Gu, Baohua, Eskelsen, Jeremy R, Jubb, Aaron M, Zhao, Linduo, Pierce, Eric M, Gobbi, Pietro, Papa, Stefano, Coccioni, Rodolfo
• Format: Article
• Language: English
• Subjects: Accumulation; Acridine; Acridine orange; Acridine Orange - analysis; Ammonia; Autophagy; BASIC BIOLOGICAL SCIENCES; Bioaccumulation; Biological magnification; Biology and Life Sciences; Biomarkers; Cell Compartmentation; Cell death; Cell membranes; Chemical analysis; Confocal; cytoplasm; Earth Sciences; Ecology and Environmental Sciences; Ecosystem; Environmental science; Fluorescence; Fluorescent indicators; foraminifera; Foraminifera - metabolism; Gene expression; Health aspects; Health hazards; Heavy metals; Hg-pollution; Intracellular; Intracellular Space - metabolism; Ion probes; Laboratories; Linings; lipid; Lipids; Lipids - analysis; lysosome; Lysosomes; Lysosomes - metabolism; Medicine and Health Sciences; Membranes; Mercury; Mercury (metal); Mercury - analysis; Physical Sciences; Pollutants; Pollution; Research and Analysis Methods; scanning electron microscopy; sea water; Seawater; Sediments; Septum; vesicles; Water analysis; Water Pollutants, Chemical - analysis; Water pollution; Water Pollution - analysis; Water treatment; Zebrafish
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0162401

Heavy metals such as mercury (Hg) pose a significant health hazard through bioaccumulation and biomagnification. By penetrating cell membranes, heavy metal ions may lead to pathological conditions. Here we examined the responses of Ammonia parkinsoniana, a benthic foraminiferan, to different concentrations of Hg in the artificial sea water. Confocal images of untreated and treated specimens using fluorescent probes (Nile Red and Acridine Orange) provided an opportunity for visualizing the intracellular lipid accumulation and acidic compartment regulation. With increased Hg over time, we observed an increased number of lipid droplets, which may have acted as a detoxifying organelle where Hg is sequestered and biologically inactivated. Further, Hg seems to promote the proliferation of lysosomes both in terms of number and dimension that, at the highest level of Hg, resulted in cell death. We report, for the first time, the presence of Hg within the foraminiferal cell: at the basal part of pores, in the organic linings of the foramen/septa, and as cytoplasmic accumulations.