Nuclear Morphology and Lysosomal Stability of Molluskan Hemocytes as Possible Biomarkers of Arsenic Toxicity

Abstract

The frequency of nuclear aberrations and neutral red retention time of hemocytes in the mollusk Lamellidens marginalis were recorded under exposure to sublethal concentrations of sodium arsenite in order to examine the sensitivity and effectiveness of these inexpensive assays for screening the toxicity of As 3+ in a freshwater ecosystem. A dose and time dependent increase in the density of micronucleated and binucleated hemocytes and gill cells was indicative of the pronounced genotoxic effect of arsenic on this animal. The disruption of intrahemocyte homeostasis imposed by this natural toxicant was evident from a dose and time dependent reduction in the lysosomal stability of the hemocytes of the animal. The tested parameters are indicative of arsenic toxicity in L. marginalis in the freshwater systems of the arsenic affected geographical areas of West Bengal, India.

Proteomic and metabolomic analysis on the toxicological effects of As (III) and As (V) in juvenile mussel Mytilus galloprovincialis

“…Therefore, the altered BCAAs might suggest the immune stress in juvenile mussel induced by As (III) and As (V) exposures. Previous studies confirmed that As exposures could induce immune stress in mollusks indicated by the altered immune effector cells haemocytes and some immune-related enzymes (acid phosphatase and phenoloxidase) (Jing et al, 2007;Chakraborty and Ray, 2009;Ray et al, 2015). The changes of all these metabolites suggested that the As (III) and As (V) exposures might induce disturbance in osmotic regulation and immune system in juvenile mussels via differential metabolic pathways.…”

Toxic Effects of Copper, Cadmium, and Methoxychlor Shown by Neutral Red Retention Assay in Two Species of Freshwater Molluscs

“…Only a few species of freshwater invertebrates have been studied using neutral red retention as a gauge of toxicity, the snails Vivparus contectus [43] and Lymnaea stagnalis [44], and the bivalves, Dreissena polymorpha [29,30], and Lamellidens marginalis [45]. Our use of a unionid bivalve, Elliptio complanata, and a planorbid snail, Helisoma trivolvis in the present study increases the number of freshwater invertebrate species tested, and both have a broad North American geographical distribution.…”

Toxicity of sodium arsenite in the gill of an economically important mollusc of India

“…Free radicals may also stimulate cell growth by damaging specific genes that control the growth rate and differentiation during the promotion phase [66]. The genotoxic effect of NaAsO 2 was found to be significantly high in gills of L. marginalis with elevated count of nuclear abnormalities accounted in the branchial epithelial cells [8]. A decrease in CAT activity indicates a reduced ability to protect cells against H 2 O 2 [67].…”

“…Gills remain in direct exposure of contaminants and are subjected to tissue damage. In L. marginalis, the genotoxic effect of arsenic was found to be significantly high with elevated count of nuclear abnormalities accounted in the branchial epithelial cells [8]. The clogging of the water channels with infiltrated hyperchromatic anaplastic cells and fibrolitic tissues, deformed and punctured branchial epithelium probably signifies a condition of possible perturbation of the normal functioning of the organ that might include inadequate water filtration, insufficient gaseous exchange and reduced in filter-feeding.…”

“…In interstitial lake water, arsenic exists in major as a highly toxic trivalent form, the arsenite [7]. Although extensively examined in mammalian system, the effects of arsenic toxicity on the freshwater invertebrates in Indian subcontinent are least documented [1,8].…”