Because there is increasing interest in the common disruption of cytokine pathways seen in both AD and schizophrenia, we tested the association between the functional interleukin-1beta -511 promoter polymorphism with delusions and hallucinations in AD.
Most genes conferring susceptibility to AD are related to amyloid-beta deposition (APP; PS1; PS2; APOE; Cystatin-C; ubiquilin-1), oxidative stress (NOS2; NOS3) and inflammatory response (IL-1 alpha; IL-1 beta; IL-6; TNF-alpha).
These findings indicate that the IL-1β-511C/T polymorphism might be associated with AD risk, and individuals with IL-1β -511C/C genotype might be at higher risk of AD in non-Europe.
TNF-α -308G/A and IL-8 -251T/A were significantly associated with AD and IL-1β+3953C/T with late-life depression, while the significance of these associations was lost after Bonferroni correction.
Because there is increasing interest in the common disruption of cytokine pathways seen in both AD and schizophrenia, we tested the association between the functional interleukin-1beta -511 promoter polymorphism with delusions and hallucinations in AD.
As further evidence of the importance of IL-1 in Alzheimer pathogenesis, two new genetic studies of inheritance of specific polymorphisms in IL-1 genes in Alzheimer and control patients show that homozygosity for a specific IL-1A gene polymorphism at least triples risk for development of Alzheimer's disease.
Interleukin-33 (IL-33), a newly described member of the IL-1 family, is located on chromosome 9p24, a chromosomal region of interest in Alzheimer's disease (AD) defined by many genome-wide studies.
Several polymorphisms associated with neuropsychiatric disorders such as schizophrenia and Alzheimer's disease have been reported at the interleukin-1 (IL-1) panel.
For example, IL-1 overexpression in the brain of Alzheimer patients relates directly to the development and progression of the cardinal neuropathological changes of Alzheimer's disease, i.e., the genesis and accumulation of beta-amyloid (Abeta) plaques and the formation and accumulation of neurofibrillary tangles in neurons, both of which contribute to neuronal dysfunction and demise.
Genetic polymorphisms of APO-E, homocysteine, and the IL-1 gene cluster (IL-1A, IL-1B, receptor antagonist IL-1RN) are associated with sporadic Alzheimer's disease and may involve interdependent pathways of neuronal toxicity.
The concomitant presence of the ACT T,T and IL-1beta T,T genotypes increased the risk of AD (odds ratio: 5.606, confidence interval: 1.654-18.996) and decreased the age at onset of the disease.
We examined the associations of hippocampal subfield volumes with age, a vascular risk factor (hypertension), and genetic polymorphisms associated with variation in pro-inflammatory cytokines levels (IL-1βC-511T and IL-6 C-174G) and risk for Alzheimer's disease (APOEε4) in healthy adult volunteers (N = 80; age = 22-82 years).
In this study, the frequency of polymorphisms in the genes coding for interleukin (IL)-1alpha, IL-1beta and the IL-1 receptor antagonist (RN) and their genotype associations with late-onset AD and VaD were determined in a Japanese-American cohort of men (n=931) participating in the Honolulu-Asia Aging Study (HAAS).
Now there is evidence that the risk of AD is substantially influenced by a total of 10 polymorphisms in the inflammatory agents interleukin 1alpha, interleukin 1beta, interleukin 6, tumor necrosis factor alpha, alpha(2)-macroglobulin, and alpha(1)-antichymotrypsin.
Compared to the IL-1β CC genotype (-31), the TT genotype significantly increased the risk of AD (TT vs. CC, adjusted OR = 1.72, 95% CI = 1.13-2.61, p = 0.010).