Preparation for oxidative stress in the subantarctic stone crab Paralomis granulosa (Crustacea: Decapoda)

ROMERO, MC; MALANGA, GABRIELA; ANSALDO, MARTIN; LOVRICH, GA

Montevideo, Uruguay

Congreso; V Meeting of the Society for free Radical Biology and Medicine – South American Group- and the V International Conference on Peroxynitrite and Reactive Nitrogen Species; 2007

Society for free Radical Biology and Medicine

<!-- /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-parent:""; margin:0cm; margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman"; mso-fareast-font-family:"Times New Roman"; mso-ansi-language:EN-GB;} @page Section1 {size:612.0pt 792.0pt; margin:70.85pt 3.0cm 70.85pt 3.0cm; mso-header-margin:36.0pt; mso-footer-margin:36.0pt; mso-paper-source:0;} div.Section1 {page:Section1;} --> the southern South America the subantarctic stone crab Paralomis granulosa constitutes the most important crustacean in the region. After their capture, animals spend several hours alive exposed to air on deck until they arrive to the fishery company where they are processed. As a direct consequence of interrupted water flow through the gills, the reactive oxygen species start to increase triggering oxidative stress. Hence, the goal of this work was to determine the levels of antioxidant enzyme activities due to air exposure in different tissues of P. granulosa. During winter 2004, 50 male crabs of legal size (carapace length >82 mm) were captured in Beagle Channel (54º 50´S, 68º 20´W). Experiments of air exposure were done using five groups of 10 crabs each, where each one was exposed to dryness at 8 ºC for 0, 3, 6, 12 or 24 h, respectively. Samples of gills, muscle, hepatopancreas and haemolymph were analized to determine enzymatic activity of superoxide dismutase (SOD), catalase (CAT) and glutathione-S transferase (GST). Furthermore, protein oxidation (PO) and lipid peroxidation (LPO) levels were measured in the same tissues.   The activity of the enzymes involved in the antioxidant defense of P. granulosa varied with the time of air exposure. The maximum enzyme activity was obtained between 3 and 6 h of air exposure. After that, values decreased to those observed at time 0. CAT and SOD showed coordinated activity in muscle, hepatopancreas and haemolymph. Gills were the only tissue where SOD activity decreased with time of air exposure. PO levels varied significantly in gills. LPO levels increased significantly in muscle and hepatopancreas. The high activity of antioxidant enzymes registered during anoxic condition was named preparation for oxidative stress. This process seems to be the key to minimize tissue damage during reoxygenation, since tissues are prepared to deal with oxyradicals. The preparation for oxidative stress in a crab that does not inhabit intertidal coastal as P. granulosa is still intriguing, and could be a feature of the intertidal lineage of this group that has been retained by the current species.