Inflammatory markers in younger vs elderly normal volunteers and in patients with Alzheimer's disease

Background. Recently it has been reported that activation of the inflammatory response system (IRS) may play a role in the aging process and in the pathogenesis of the degenerative changes associated with Alzheimer's disease (SDAT). The aims of the present study were to examine the peripheral IRS in normal aging and in SDAT patients. Methods. Serum zinc (Zn), total serum protein (TSP), albumin (Alb), SP electrophoresis, and serum interleukin-6 (IL-6) and the stimulated production of tumor necrosis factor-α (TNFα) were determined in younger versus elderly healthy subjects and in SDAT patients vs age-matched, healthy volunteers. Results. Serum Zn and Alb were significantly lower in elderly than in younger healthy volunteers and were significantly and inversely correlated with age. The production of TNFα was significantly higher in elderly than in younger healthy volunteers and was significantly and positively correlated with age. In SDAT patients, no significant changes in serum Zn or TNFα production could be found. Serum Alb was significantly lower and serum IL-6 and the α1 and α2 globulin fractions significantly higher in SDAT patients than in controls. Conclusions. Activation of the IRS appears to accompany the normal aging process, i.e. lower serum Zn and Alb and increased TNFα production, as well as SDAT, i.e. lower serum Alb and increased serum IL-6 and α1 and α2 globulin fractions. The findings suggest that not all indicators of IRS activation in SDAT are related to those of the normal ageing process.