Age-Related Differences in Cytokine Secretion

Abstract

The aim of the present study was to compare cytokine secretion in healthy young and old subjects. Peripheral blood mononuclear cells were isolated from 55 healthy volunteers (aged 23-77 years) and cultured for 24 h in the presence or the absence of lipopolysaccharide (LPS) and 1,25-dihydroxyvita-min D₃. Interleukin-lΒ (IL-1), tumor necrosis factor a (TNF) and prostaglandin E₂ were measured in the culture superna-tants with specific immunoassays. The unstimulated and LPS-stimulated production of IL-1 was significantly higher in the group of subjects older than 55 years than in the group aged less than 55 years. Likewise, there were positive correlations between age and the unstimulated and LPS-stimulated IL-1 secretion (r= 0.50 and 0.63, respectively, p < 0.01 in both cases). However, there were no age-related differences in the secretion of IL-1 in the presence of 1,25-dihydroxyvitamin D or in the secretion of TNF or prostaglandin E₂ in any culture condition. These results suggest the existence of subtle abnormalities in cytokine secretion in healthy aged subjects, in comparison with younger individuals. In theory, the increased secretion of IL 1 might play a role in the pathophysiology of some diseases which are frequent in old people, such as osteoporosis.

Effects of aging and menopause on serum interleukin-6 levels and peripheral blood mononuclear cell cytokine production in healthy nonobese women

“…However, von Haehling et al (2003 determined that a significant correlation exists between age and TNF-α production by PBMCs. Riancho et al (1994) showed a positive correlation between age and IL-1β levels, but not TNF-α, in supernatants from isolated human monocyte cultures stimulated with LPS for 24 h. On the other hand, Bruunasgaard et al (1999) reported decreased levels of TNF-α and IL-1β in whole blood supernatants following LPS stimulation from the elderly, as compared to younger individuals. There was no difference with regard to IL-6 levels.…”

Critical role of the liver CD8+ CD122+ T cells in the generalized Shwartzman reaction of mice

“…The mechanisms of such vulnerability to infections in the elderly have been ascribed to a breakdown in the anatomic barriers, underlying illnesses, or the declining capacity of the immune system [6][7][8][9]. Although many investigators have attempted to characterize the response to infection in aged animals, their attempts have produced equivocal results; some studies have shown a decreased response in aged hosts [10][11][12][13][14], while others have not [15][16][17][18].…”

Increased Prostaglandin E₂ Production by Concanavalin A-Stimulated Splenocytes of Old Mice

“…A similar argument may apply to the studies of Riancho et al [16] on human cells, which failed to demonstrate an age-related increase in PGEi production by activated peripheral blood mononuclear cells from healthy people, younger and older than 55 years. A trend of an increase, although statistically nonsignificant, in PGE2 production by Con A-stimulated splenocytes was noted in 24-month-old as compared to 3-month-old C57BL/6NNia mice [12], in line with our data on 18-to 23-month-old mice in the present study.…”