title: Immunolocalization of metallothionein in hepatocytes of guppy fish (Poecilia reticulata) exposed to tannery effluent: A biomarker study.
abstract: Composite tannery effluent (TE) contaminated with a load of metals, especially chromium, is used in East Calcutta Wetland Ecosystem (ECW; a Ramsar site of West Bengal; No 1208) after natural stabilization for pisciculture and agriculture. Quantity and synergistic and antagonistic activities of both essential and nonessential metals in the effluents can induce a variety of complex changes in animal physiology. High fish yield and no apparent adverse influence on the fish biosystems thriving under pollutant stress at ECW allowed the practice to thrive sustainably over the last nearly 100 years. Thus, the present study was conducted to investigate the role of metallothionein (MT) as a potential biomarker in a fish biosystem following acute and chronic exposure to sublethal concentrations of tannery wastewater. MT localization in the liver tissue of guppy fish (Poecilia reticulata) was studied by the immuno gold-labeled electron microscopic technique. The data demonstrated increased metal content in fish body upon exposure to TE. Electron micrographs showed significant induction of hepatic MT in exposed P. reticulata over control specimens. Liver, being the detoxification site of an organism, plays a crucial role in the synthesis of MT and arrest of excess metal. The method employed in the present study for demonstrating the induction and localization of MT is innovative and could be used as a biomarker in fish exposed to metal stress. Our study also indicated that the metalloprotein complexes in fish tissue sequestered excess load of metals and thereby arrested unwanted interferences of excess metal loads in metabolic processes.
authors.affiliation: Government College of Engineering and Leather Technology, Sector III, Block LB Salt Lake, Kolkata, 700 098, West Bengal, India. Electronic address: aanulipi@gmail.com.
authors.forename: Anulipi
authors.initials: A
authors.lastname: Aich
authors.affiliation: Government College of Engineering and Leather Technology, Sector III, Block LB Salt Lake, Kolkata, 700 098, West Bengal, India. Electronic address: cbuddhadeb@gmail.com.
authors.forename: Buddhadeb
authors.initials: B
authors.lastname: Chattopadhyay
authors.affiliation: Government College of Engineering and Leather Technology, Sector III, Block LB Salt Lake, Kolkata, 700 098, West Bengal, India. Electronic address: subhro22@gmail.com.
authors.forename: Subhra Kumar
authors.initials: SK
authors.lastname: Mukhopadhyay
mesh_terms: D000818:Animals; D015415:Biomarkers / Q000378:metabolism*; D022781:Hepatocytes / Q000187:drug effects / Q000378:metabolism*; D008658:Inactivation, Metabolic / Q000187:drug effects; D008099:Liver / Q000187:drug effects / Q000378:metabolism*; D008668:Metallothionein / Q000378:metabolism*; D008670:Metals / Q000633:toxicity*; D011036:Poecilia / Q000254:growth & development / Q000378:metabolism*; D062065:Wastewater; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D015415:Biomarkers; D008668:Metallothionein; D008670:Metals; D062065:Wastewater; D014874:Water Pollutants, Chemical
keywords: Biomarker; East Calcutta Wetland (ECW); Immunocytochemistry (electron microscopy); Metallothionein; Metals; Tannery effluent