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Made available in DSpace on 2019-09-12T16:53:35Z (GMT). No. of bitstreams: 0 Previous issue date: 2017 Ministério do Meio Ambiente (MMA) Ministério da Ciência, Tecnologia e Inovação (MCTI) Secretaria da Comissão Interministerial para os Recursos do Mar (SECIRM) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ) The gastropod Nacella concinna is the most conspicuous macroinvertebrate of the intertidal zone of the Antarctic Peninsula and adjacent islands. Naturally high levels of copper and cadmium in coastal marine ecosystems are accumulated in N. concinna tissues. We aimed to study the effects of metal cations on N. concinna arginase in the context of possible adaptive microevolution. Gills and muscle had the highest argininolytic activity, which was concentrated in the cytosol in both tissues. Gills had the highest levels of arginase and may be involved in the systemic control of L-arginine levels. The relatively high argininolytic activity of the N. concinna muscular foot, with K-M = 25.3 +/- 3.4 mmol L-1, may be involved in the control of L-arginine levels during phosphagen breakdown. N. concinna arginases showed the following preferences for metal cations: Ni2+ > Mn2+ > Co2+ > Cu2+ in muscle and Mn2+ > Cu2+ in gills. Cu2+ activation is a unique characteristic of N. concinna arginases, as copper is a potent arginase inhibitor. Cu2+ partly neutralized N. concinna arginase inhibition by Cd2+, worked synergistically in muscle arginase activation by Co2+ and neutralized muscle arginase activation by Ni2+. Mn2+ was able to activate muscle arginase in the presence of Fe3+ and Pb2+. The selection of arginases that are activated by Cu2+ and resistant to inhibition by Cd2+ in the presence of Cu2+ over evolutionary timescales may have favored N. concinna occupation of copper- and cadmium-rich niches. (C) 2016 Elsevier Inc. All rights reserved. [de Oliveira, Mariana Feijo; Rodrigues Junior, Edson; Kawagoe Suda, Cecilia Nahomi; Vani, Gannabathula Sree; Rodrigues, Edson] Universidade de Taubaté (Unitau), Basic Biosci Inst [Donatti, Lucelia] Univ Fed Parana, Dept Cell Biol, Curitiba, Parana, Brazil [Lavrado, Helena Passeri] Univ Fed Rio de Janeiro, Dept Marine Biol, Rio De Janeiro, Brazil

Made available in DSpace on 2019-09-12T16:53:39Z (GMT). No. of bitstreams: 0 Previous issue date: 2015 Ministério do Meio Ambiente (MMA) Ministério da Ciência, Tecnologia e Inovação (MCTI) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Secretariat of the Inter-ministerial Commission for the Resources of the Sea (SeCIRM) Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ) Instituto Nacional de Ciência e Tecnologia Antártico de Pesquisas Ambientais (INCT-APA) The intertidal and subtidal environments in the Antarctic Peninsula are vulnerable to pollutants, such as diesel oil, a commonly used fuel. Nacelle concinna is capable of accumulating polycyclic aromatic hydrocarbons and is a potential biomonitor of diesel oil contamination. This work investigates the interaction of diesel oil, temperature and salinity on the activity of antioxidants enzymes defense of the gills, foot muscle and digestive glands. Upregulation of superoxide dismutase occurred in the three tissues by warming. The foot muscle catalase and the gill glutathione reductase were upregulated only by diesel. The inability to upregulate catalase and glutathione S-transferase in the digestive gland, as well as the increase of lipoperoxidation, suggested that this gland is more susceptible to the deleterious effects from oxidative stress. (C) 2015 Elsevier Ltd. All rights reserved. [de Oliveira, Mariana Feijo; Rodrigues Junior, Edson; Donatti, Lucelia] Univ Fed Parana, Dept Cell Biol, BR-81530130 Curitiba, Parana, Brazil [de Oliveira, Mariana Feijo; Rodrigues Junior, Edson; Suda, Cecilia N. K.; Vani, Gannabathula S.; Rodrigues, Edson] Universidade de Taubaté (Unitau), Basic Biosci Inst, BR-12030180 Taubate, SP, Brazil [Lavrado, Helena P.] Univ Fed Rio de Janeiro, Dept Marine Biol, BR-21941902 Rio De Janeiro, RJ, Brazil

Made available in DSpace on 2019-09-12T16:53:28Z (GMT). No. of bitstreams: 0 Previous issue date: 2015 Ministério do Meio Ambiente (MMA) Ministério da Ciência, Tecnologia e Inovação (MCTI) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Secretariat of the Inter-ministerial Commission for the Resources of the Sea (SeCIRM) Instituto Nacional de Ciência e Tecnologia Antártico de Pesquisas Ambientais (INCT-APA) Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ) The present study aimed to assess the sewage effects of the Brazilian Antarctic Station Comandante Ferraz, Admiralty Bay, King George Island, on the hepatic metabolism (energetic, antioxidant, and arginase levels) and levels of plasma constituents of two Antarctic fish species Notothenia rossii and N. coriiceps. The bioassays were conducted under controlled temperature (0 degrees C) and salinity (35 psu), exposing the fish for 96 h, to sewage effluent diluted in seawater to 0.5 % (v/v). Liver homogenates were tested for the specific activities of the enzymes glucose-6-phosphatase (G6Pase), glycogen phosphorylase (GPase), hexokinase, citrate synthase, lactate dehydrogenase, malate dehydrogenase, glucose-6-phosphate dehydrogenase, superoxide dismutase, glutathione reductase, catalase, and arginase. Plasma levels of glucose, triacylglycerides, cholesterol, total protein, albumin, chloride, magnesium, calcium, and inorganic phosphate were also determined. In N. rossii, the decrease in citrate synthase and the increase in G6Pase and GPase suggested that the sewage effluent activated glycogenolysis and hepatic gluconeogenesis, whereas is N. coriiceps, only G6Pase levels were increased. In N. rossii, sewage effluent induced hypertriglyceridemia without modulating glucose plasma levels, in contrast to N. coriiceps, which developed hypoglycemia without elevating plasma triglyceride levels. The decrease in glutathione reductase levels in N. coriiceps and in superoxide dismutase and catalase in N. rossii suggest that these two species are susceptible to oxidative stress stemming from the production of reactive oxygen species. An increase in magnesium in N. rossii and a decrease in N. coriiceps showed that sewage effluent compromised the control of plasma levels of this cation. Although phylogenetically close, both species of Antarctic fish exhibited different metabolic responses to the sewage effluent, with N. coriiceps showing greater susceptibility to the toxic effects of the pollutants. The present study suggests that the biochemical responses of these two species are potential indicators of metabolic changes caused by sewage effluents. [Rodrigues, Edson, Jr.; Feijo-Oliveira, Mariana; Kawagoe Suda, Cecilia Nohome; Vani, Gannabathula Sree; Rodrigues, Edson] Universidade de Taubaté (Unitau), Inst Basic Biosci, BR-12030180 Taubate, SP, Brazil [Donatti, Lucelia] Univ Fed Parana, Dept Cell Biol, BR-81530130 Curitiba, PR, Brazil [Lavrado, Helena Passeri] Univ Fed Rio de Janeiro, Dept Marine Biol, BR-21941902 Rio De Janeiro, RJ, Brazil