Chemokines and pro-inflammatory cytokines in Down's syndrome: An early marker for Alzheimer-type dementia?

Background. People with Down's syndrome (DS) show early Alzheimer-like dementia. It has been suggested that the pro-inflammatory cytokine class plays a role in Alzheimer's disease (AD). The study aims at verifying whether pro-inflammatory cytokines in DS are correlated with age, affective symptoms and intellectual decline to a different degree than in subjects with non-DS learning disabilities. Methods: Cases: 19 subjects with DS; controls: sex- and age-matched individuals with learning disabilities caused by perinatal ischaemic damage. The level of mental retardation was assessed according to DSM-IV; psychopathological symptoms were measured by the Assessment and Information Rating Profile. Serum levels of cytokines were determined with ELISA. Results: DS patients showed higher levels of cytokines and chemokines, with the exception of RANTES; but the only significant difference detected was for MIP-1alpha. A correlation between the degree of mental retardation and IL-6, and between MIP-1alpha and age was found in patients with DS, but not in controls. Conclusions: The data obtained suggest a possible involvement of chemokines in the inflammatory and degenerative processes similar to AD in DS. Further longitudinal research is required to confirm these findings.