Aim: 

Hormesis has emerged as an important manipulation of mild stress-induced stimulation resulting in protective mechanisms for cells and organisms. The exposure to low doses of otherwise harmful agents has a variety of healthful and longevity-extending hormetic effects. The function and redox state of immune cells are good markers of health and longevity. The aim of the present work is to study if the administration of bacterial endotoxin lipopolysaccharide in very low dose on mature prematurely aging mice (animals with immunosenescence and oxidation state) stimulates several functions and oxidative stress parameters in immune cells.

Methods: 

prematurely aging mice, twelve months old, received four injections of 0.1 mg/kg of bacterial endotoxin lipopolysaccharide from Escherichia coli (hormesis group) or PBS (control group), during 2 moths with an interval of 15 days. After the last injection peritoneal cells were obtained and the microbicidal capacity (by intracellular superoxide anion levels), natural killer activity, extracellular superoxide anion levels and catalase activity, were analysed.

Results: 

The results showed an increase of the microbicidal and natural killer capacities as well as of catalase activity in immune cells from the mice submitted to hormesis with respect to the controls.

Conclusion: 

In premature aging mice, a mild and periodic infection challenge is a good hormesis intervention to improve the immune cell conditions and reach a healthy aging.

Supported: F.I.Mutua Madrileña; MICINN (BFU2008-04336), Research Group UCM (910379ENEROINN); RETICEF (RD06/0013/0003).