Associations of cytokine genes with Alzheimer's disease and depression in an elderly Korean population

Abstract

The present findings support the inflammatory hypothesis in the aetiology of AD as measured by several cytokine genes associated with increased proinflammatory cytokine production.

Inflammatory Cytokines and Alzheimer’s Disease: A Review from the Perspective of Genetic Polymorphisms

“…According to the two recent meta-analyses, IL-10 -1082G may be associated with reduced AD risk, particularly among Europeans [40,41]. However, negative results were reported in two studies conducted in Asia [112,119]. Moreover, contradictory conclusions have been drawn by Moraes et al, who very recently found a significant association between the IL-10 -1082 AA genotype and decreased AD risk in a large sample in Brazil [42].…”

“…The significance of the SNPs might be related to the control of IL-4 gene transcription or IL-4 protein expression [110,111]; this would result in an imbalance between pro-and anti-inflammatory cytokines and ultimately accelerate the AD process. The ?33 T/C polymorphism of IL-4 has been identified and was assumed to affect AD risk, but negative results have been obtained in all three relevant studies conducted with Asians [39,112,113].…”

Targeting of Tumor Necrosis Factor Alpha Receptors as a Therapeutic Strategy for Neurodegenerative Disorders

“…On a genetic level, multiple polymorphisms in the TNF-α gene may be associated with the risk of developing AD [79]. For example, the TNF-α G308A promoter polymorphism, which may cause higher TNF-α expression levels, has been found to increase the risk of AD in certain populations [80][81][82]. At the protein level, plasma and serum TNF-α protein levels are elevated in AD [83][84][85].…”

Alzheimer’s disease and cytokine IL-10 gene polymorphisms: is there an association?

“…TNF-α and IL-8 were significantly associated with AD, and IL-1β with late-life depression. They found no significant association between anti-inflammatory cytokine gene polymorphisms and AD or late-life depression 53 . Vargas-Alarcón et al 54 conducted the first study in a Mexican population that considered the analysis of IL-10 SNPs in patients with AD, vascular dementia and mixed dementia (AD/vascular dementia).…”

“…Their findings showed an almost 40% lower chance of AD among homozygotes of the IL-10 -1082A allele 42 . Kang et al 53 investigated the involvement of alleles associated with higher production of proinflammatory and lower production of anti-inflammatory cytokines in 732 elderly Korean individuals with AD or depression. Genotyping was performed for six pro-inflammatory (IL-1β, IL-6, IL-8, TNF-α) and two anti-inflammatory (IL-4 and IL-10-1082A/G) cytokines genes.…”