Antioxidant defenses participation during hypometabolism induced by short-term estivation

AGÜERO, R; GIRAUD BILLOUD, M.

Mendoza

Simposio; 2º Simposio Internacional de Medicina Traslacional y XIV Jornadas de Investigación de la FCM; 2019

Facultad de Ciencias Médicas, Universidad Nacional de Cuyo

Animals respond through different adaptive strategiesto environmental stressors (i.e. temperature or humidity changes, availability of water andfood). The ampullariid Pomaceacanaliculata is capable of support hypometabolic situations induced byextreme environmental conditions such as drying out of water bodies thatinhabit (estivation) and/or cold temperatures (hibernation). Thequiescence-activity cycles determined by the entry and exit (arousal) of thehypometabolic situation activate defenseprotective mechanisms, which in the long term; involve glutathione, uric acid and heat shock proteins. The possibletranslational application of thisischemia-reperfusion experimental model requires knowledge of themechanisms involved in tissue protection to hypoxia. Our hypothesis assumesthat our acute hypometabolism model will activate antioxidant defense mechanisms to counteract the damageinduced by the increase in free radicals that occurred during hypoxia. Westudied the digestive gland, lung andgill of three experimental groups: control, 7 day estivation and 30 minutearousal and we measured lactate produced during hypoxia, the damage caused byoxidative stress (TBARs), the total antioxidant capacity in the sample (ABTS)and we determined some enzymatic antioxidant activities and quantified the mainnon-enzymatic antioxidant of this animal, uric acid. We observed that the onlyorgan that showed oxidative damage during the estivationwas digestive gland, with increased TBARs levels, but also showed increase in totalantioxidants, catalase (CAT) activity and uric acid. Nevertheless, in bothrespiratory organs gill and lung, CAT levels rise significantly duringestivation and in lung uric acid decrease significantly. These results showedthat during acute hypometabolic situation induced by estivation enzymaticdefences protects all tissues and uric acid contribute in the lung protectionto hypoxia. New studies focusing in the activation of antioxidant defences couldhead light in molecular mechanisms related to preparation for oxidative stressstrategy used for this animal species during quiescence-activity cycles.