Aging is associated with circulating cytokine dysregulation.
OBJECTIVE
Aging is accompanied by a progressive increase in pro-inflammatory cytokine status. However, little is known about the development of age-dependent modifications in other circulating cytokines. The aim of this study was to investigate in vivo the influence of age on circulating cytokine production in healthy subjects (HC).


METHODS
Circulating cytokines were measured by CBA and ELISA in 73 HC. Intracellular cytokine production was assessed in CD3+ and CD14+ cells by flow cytometry. Production of cytokines in cell culture supernatants was also studied after polyclonal stimulation.


RESULTS
Subjects were divided into three different groups according to age: 28 young HC (<30 years, 26.2 ± 2.4), 24 middle age HC (30-60 years, 44.7 ± 8.4) and 21 elderly HC (>60 years, 70.6 ± 7.9). Age was positively correlated with the circulating levels of IL-12p70, IL-1β, TNFα, IL-6, and IL-10. Age had a negative correlation with circulating levels of IL-17. Besides, age was positively correlated with spontaneous intracellular expression of proinflammatory cytokines in circulating monocytes. No correlation was found with other intracellular cytokine expression or with the production of cytokines in cell culture supernatants after in vitro stimulation. Gender had a marginal effect on the circulating cytokine profile.


CONCLUSIONS
Aging has a significant impact on the production of circulating cytokines in healthy individuals. The circulating cytokine milieu may contribute to the development of age-restricted conditions.
Division of Rheumatology, Hospital Universitario Marqués de Valdecilla-IFIMAV, Facultad de Medicina, Universidad de Cantabria, Santander, Spain.
Lorena
L
Alvarez-Rodríguez
Marcos
M
López-Hoyos
Pedro
P
Muñoz-Cacho
Víctor Manuel
VM
Martínez-Taboada
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000097:blood / Q000276:immunology*; D017252:CD3 Complex / Q000276:immunology; D002478:Cells, Cultured; D016207:Cytokines / Q000096:biosynthesis / Q000097:blood* / Q000276:immunology; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D018950:Lipopolysaccharide Receptors / Q000276:immunology; D008297:Male; D008875:Middle Aged; D009000:Monocytes / Q000166:cytology / Q000276:immunology*; D013601:T-Lymphocytes / Q000166:cytology / Q000276:immunology*; D058408:Th1-Th2 Balance
D017252:CD3 Complex; D016207:Cytokines; D018950:Lipopolysaccharide Receptors