Thyroid hormone-mediated regulation on intracellular glutathione concentration and antioxidant enzyme activity in lymphoid tissue of Balb/c mice

MACRI DELBONO R.; KLECHA A.; BARREIRO ARCOS M.L.; CONTIN M.; ROMEO H.; TRIPODI V.; COSTILLA M.; CREMASCHI G.

on line

Congreso; Annual Meeting 2021 - SAFIS- ALACF; 2021

Sociedad Argentina de Fisiología (SAFIS); Asociación Latinoamericana de Ciencias Fisiológicas (ALACF)

Introduction: Thyroid hormones (TH) regulate metabolism and redox status in most tissues. We previously demonstrated that TH increase reactive oxygen species (ROS) in lymphoid cells. However, the antioxidant defense mechanisms involved in ROS clearance have not yet been elucidated. Objectives: To analyze the intracellular glutathione content, the GSH/GSSG ratio and the activity or expression of antioxidant enzymes in lymphoid tissue from euthyroid and hyperthyroid mice. Methods: Hyperthyroidism was induced in Balb/c mice by treatment with thyroxine in drinking water (12 mg/ml) for 40 days. Lymphoid cells from lymph nodes (LN) and spleen (S) were purified for biological assays. Assessment of GSH and GSSG was performed by liquid chromatography and tandem mass spectrometry (HPLC-MS/MS). Catalase (CAT) and Glutathione peroxidase-1 (GPx-1) expression was quantified by real-time PCR and western blot. The conversion of H2O2 to molecular oxygen by CAT was determined by spectrophotometry. ROS were evaluated by DCFH-DA staining and flow cytometry. Results: We found that GSH and GSSG were increased in LN and S from hyperthyroid mice, and the GSH/GSSG ratio was similar to euthyroid mice (% increase- GSH LN: 30.2±2.1, GSH S: 29.6±1.8; GSSG LN: 32.4±2.9, GSSG S: 31.7±2.7; n=5; p