Hyperthyroidism in the developing rat testis is associated with oxidative stress and hyperphosphorylated vimentin accumulation.
Hyperthyroidism was induced in rats and somatic indices and metabolic parameters were analyzed in testis. In addition, the morphological analysis evidenced testes maturation and intense protein synthesis and processing, supporting the enhancement in vimentin synthesis in hyperthyroid testis. Furthermore, vimentin phosphorylation was increased, indicating an accumulation of phosphorylated vimentin associated to the cytoskeleton, which could be a consequence of the extracellular-regulated kinase (ERK) activation regulating the cytoskeleton. Biomarkers of oxidative stress demonstrated an increased basal metabolic rate measured by tissue oxygen consumption, as well as, increased TBARS levels. In addition, the enzymatic and non-enzymatic antioxidant defences appeared to respond according to the augmented oxygen consumption. We observed decreased total glutathione levels, with enhancement of reduced glutathione, whereas most of the antioxidant enzyme activities were induced. Otherwise, superoxide dismutase activity was inhibited. These results support the idea that an increase in mitochondrial ROS generation, underlying cellular oxidative damage, is a side effect of hyperthyroid-induced biochemical changes by which rat testis increase their metabolic capacity.
Zamoner
Ariane
A
Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, UFRGS, Porto Alegre, RS, Brazil.
Barreto
Kátia Padilha
KP
Filho
Danilo Wilhelm
DW
Sell
Fabíola
F
Woehl
Viviane Mara
VM
Guma
Fátima Costa Rodrigues
FC
Silva
Fátima Regina Mena Barreto
FR
Pessoa-Pureur
Regina
R
D000818:Animals; D001835:Body Weight; D004798:Enzymes; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism; D005786:Gene Expression Regulation; D005978:Glutathione / Q000378:metabolism; D015292:Glycoprotein Hormones, alpha Subunit / Q000097:blood; D006980:Hyperthyroidism / Q000139:chemically induced / Q000473:pathology*; D015227:Lipid Peroxidation; D008297:Male; D009929:Organ Size; D018384:Oxidative Stress; D010101:Oxygen Consumption; D010766:Phosphorylation; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D013737:Testis / Q000166:cytology / Q000254:growth & development* / Q000648:ultrastructure; D013963:Thyroid Hormones / Q000097:blood; D014746:Vimentin / Q000235:genetics / Q000378:metabolism*
D004798:Enzymes; D015292:Glycoprotein Hormones, alpha Subunit; D012333:RNA, Messenger; D013963:Thyroid Hormones; D014746:Vimentin; D048049:Extracellular Signal-Regulated MAP Kinases; D005978:Glutathione