Effects of oxidative stress on lymphocyte functionality in a murine model of hyperthyroidism. Role of the cellular antioxidant system in the scavenging of oxygen free radicals

ROMEO, H.; BARREIRO ARCOS, M.L.; COSTILLA, M.; CREMASCHI, G.A..; MACRI DELBONO, R.; KLECHA, A.J.

Buenos Aires

Congreso; Reunión de Sociedades de Biociencias 2020; 2020

Sociedad Argentina de Investigación Clínica (SAIC)- Sociedad Argentina de Inmunología (SAI)- Sociedad Argentina de Fisiología (SAFIS)

Introduction: Thyroid hormones increase cellular metabolism and the production of reactive oxygen species (ROS). ROS could act as a signaling molecule involved in cell functionality or exert cytotoxic actions depending on its intracellular concentration. The harmful effects of ROS are counteracted by the cellular antioxidant system. Objective: To study the effects of oxidative stress on lymphocyte functionality in hyperthyroid mice, analyzing the role of antioxidant enzymes in the scavenging of ROS. Methods: Balb/c mice were treated with placebo (euthyroids) or T4 (12 mg/l drinking water for 30 days-hyperthyroids). ROS were evaluated by DCFH-DA staining and flow cytometry. The expression of catalase (CAT), glutathione peroxidase (GPx) and superoxide dismutase (SOD) was determined by qPCR and WB. Apoptosis was evaluated by Annexin V-PI, Rhodamine-123 or Hoechst-33342 staining followed by flow cytometry or fluorescence microscopy. The number of follicles in lymphoid tissue sections stained with hematoxylin-eosin was determined by microscopy. Cell size and granularity was evaluated by flow cytometry. Proliferation was evaluated by incorporation of [3H]-thymidine. Results: We found an increased production of ROS in the lymph nodes (LN) and spleen (S) of hyperthyroid mice (% increase LN:60.6±5.1; S:63.5±5.9, p