Proteomic and metabolomic responses of clam Ruditapes philippinarum to arsenic exposure under different salinities

Abstract

a b s t r a c t Arsenic (As) contamination is a severe problem in the intertidal zones of the Bohai Sea (China) with wide salinity variation. In the present study, we combined proteomics and metabolomics to characterize the differential responses of arsenic in clam Ruditapes philippinarum under different salinities (31.1, 23.3 and 15.6 psu). Both proteomic and metabolomic responses indicated that varying salinities could significantly affect the toxicological responses of clams to As. Metabolic biomarkers revealed that the environmentally relevant arsenic (20 g L −1 ) exposure induced disturbance in energy metabolism and/or osmotic regulation under different salinities, whereas protein biomarkers indicated oxidative stress, cellular injury and apoptosis and disturbance in energy metabolism. In addition, the up-regulated proteins including ATP synthase, succinyl-CoA synthetase and nucleoside diphosphate kinase were validated by related metabolites, succinate and ATP, which confirmed the disturbance in energy metabolism in clam gills at low salinity (15.6 psu). These findings provide important insights into toxicological effects of environmental contaminant at molecular levels using combined proteomics and metabolomics.

A comparative proteomic study on the effects of metal pollution in oysters Crassostrea hongkongensis

“…The significant alterations of these seven cytoskeleton-related proteins (actin, F-actin-capping protein, twinfilin, actin-depolymerizing factor, cofilin, myosin regulatory light chains and tubulin-specific chaperone A) confirmed the cellular injury in oysters induced by metal pollution in BJ site. In numerous previous studies, some of these proteins such as actin, actin-depolymerizing factor, myosin regulatory light chain and F-actin-capping protein, were responsive to environmental stressor (e.g., arsenic, salinity, tetrabromobisphenol A)-induced oxidative stress in animals (Wu et al, 2013b;Ji et al, 2013). In this work, these altered proteins confirmed the oxidative stress and subsequent cellular injury in cytoskeleton induced by metal pollution in oysters collected from BJ site.…”

Metabolite and gene expression responses in juvenile flounder Paralichthys olivaceus exposed to reduced salinities

“…3H). In a previous study, the GST activity was also decreased in clam Ruditapes philippinarum under this hyposaline condition that could induce oxidative stress in clams and resulted in redox balance alterations [19]. In the low salinity (15.6‰) treatment, CAT was significantly (P < 0.05) upregulated (Fig.…”

“…Sry-related high mobility group box 9 (SOX 9) is one of the most important transcription factors in gonadal differentiation in vertebrates [18]. As known anti-oxidative enzymes, superoxide dismutase (SOD, EC 1.15.1.1), glutathione Stransferases (GST, EC 2.5.1.18) and catalase (CAT, EC 1.11.1.6) are usually used as scavengers for reactive oxidative species (ROS) to reduce oxidative stress in organisms [19]. NADH dehydrogenase, lactate dehydrogenase (LDH) and ATP synthase are three known enzymes involved in energy metabolism.…”

Comparative investigations on the biological effects of As (III) and As (V) in clam Ruditapes philippinarum using multiple biomarkers

“…As shown in Table 1, the total arsenic concentrations between As (III) and As (V) treatments were not significantly different (p > 0.05). In our previous study, As (V) treatment induced significant expression of arsenite-resistance protein in clam R. philippinarum, which meant that As (V) could be transformed into As (III) in clams [27]. Therefore, As (III) and As (V) exposures might induce both similar and differential biological effects in clams.…”

“…In both arsenic treatments, however, SOD activities were not significantly altered (p > 0.05), which probably meant that both chemical forms of arsenic exposures did not induce excessive superoxide anions in clam digestive gland. Both glutathione S-transferase (GST, EC 2.5.1.18) and glutathione (24) homarine, (25) b-glucose, (26) a-glucose, (27) glycogen, (28) peroxidase (GPx, EC 1.11.1.9) are related to GSH cycles promoting the conversion of GSH to resist the oxidative stress caused by environmental stressors. However, both GST and GPx activities were depleted in As (V)-treated clam samples with p values approaching or less than 0.05, respectively (Table 1), which might be accounted for the down-regulated synthesis of GST and GPx caused by As (V) in clam samples.…”