Aim: 

The purpose of this study was to investigate the effect of aging on various physiological parameters related to inflammation, apoptosis, oxidative stress and NFkB expression in hearts from male senescence-accelerated mice (SAMP-8) and the influence of chronic administration of growth hormone (GH).

Methods: 

Thirteen old male mice (10 months of age) were used. Animals were divided into two groups. Group one was treated with GH (2 mg/kg/day/subcutaneous) for 30 days and the other group was treated with saline, for the same time (control group). After treatment mice were sacrificed by decapitation. Six male mice (2 months old) were used as young controls. The expression of tumor necrosis factor-alpha (TNFa), interleukin 1 (IL-1), interleukin 10 (IL-10), endothelial nitric oxide synthase (eNOS), inducible nitric oxide synthase (iNOS), BAD, BAX, BCL2 and NFkB were determined by real-time reverse transcription polymerase chain reaction. Results were submitted to statistical evaluation with a two way ANOVA using the Statgraphics program.

Results: 

Pro-inflammatory cytokines (TNFa, IL-1), as well as expression of NFkB and BAD were increased while anti-inflammatory IL-10 decreased in the old control males as compared to young mice (p<0.05). Increased age also diminished the levels of eNOS (p<0.05). These effects were partially reverted by exogenous GH administration (p<0.05). No significant differences were observed for iNOS, BAX and BCL2 expression.

Conclusion: 

These results suggest that the inflammatory process and mediators of apoptosis could play a relevant role in the cardiovascular alterations related to aging and that GH may play a potential protective effect during this stage.

This work has been possible trough a RETICEF RD 06/0013, grant from the Instituto Carlos III. Katherine Forman was supported by CONICYT Pre-Doctoral Fellowship, Chile.