Redox imbalance influence in the myocardial Akt activation in aged rats treated with DHEA.
This study examined, in young and old (3 and 24 month-old, respectively) healthy Wistar rats, the in vivo effect of DHEA (10 mg/kg body weight) administered subcutaneously for 5 weeks. Reduced (GSH) and oxidized (GSSG) glutathione levels, glucose-6-phosphate dehydrogenase (G6PDH), glutathione peroxidase (GPx), glutathione-S-transferase (GST) and thioredoxin (Trx) reductase activities, hydrogen peroxide steady-state concentration and Nrf2, GST, Trx-1, Akt and p-Akt expressions were assessed in heart tissue. DHEA treatment significantly increased GST activity in 3 and 24 month-old treated groups. The aging factor diminished hydrogen peroxide concentration and Nrf2 expression, independently of treatment. However, the aging process increased GST, Akt and p-Akt expressions in both 24 month-old groups. The aged group responded differently to DHEA respective to GSSG content, GPx activity and p-Akt concentration. Further studies are needed to form conclusions about the efficacy and safety of DHEA replacement in the elderly, and to better understand DHEA's net effect on oxidative stress parameters and its modulation of signaling cascades.
Jacob
Maria Helena Vianna Metello
MH
Laboratório de Interação Neuro-Humoral, ICBS, Universidade Federal do Rio Grande do Sul, Brazil. mhvmjacob@hotmail.com
Janner
Daiane da Rocha
Dda R
Araújo
Alex Sander da Rosa
AS
Jahn
Matheus Parmegiani
MP
Kucharski
Luiz Carlos Rios
LC
Moraes
Tarsila Barros
TB
Dutra Filho
Carlos Severo
CS
Ribeiro
Maria Flavia Marques
MF
Belló-Klein
Adriane
A
D000375:Aging / Q000378:metabolism*; D000818:Animals; D003687:Dehydroepiandrosterone / Q000494:pharmacology*; D019803:Glutathione Disulfide / Q000378:metabolism; D005979:Glutathione Peroxidase / Q000378:metabolism; D005982:Glutathione Transferase / Q000378:metabolism; D006321:Heart / Q000187:drug effects; D008297:Male; D023421:Models, Animal; D009206:Myocardium / Q000378:metabolism*; D051267:NF-E2-Related Factor 2 / Q000378:metabolism; D010084:Oxidation-Reduction / Q000187:drug effects; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar
D051267:NF-E2-Related Factor 2; D003687:Dehydroepiandrosterone; D005979:Glutathione Peroxidase; D005982:Glutathione Transferase; D051057:Proto-Oncogene Proteins c-akt; D019803:Glutathione Disulfide