Association of an interleukin 1 alpha polymorphism with Alzheimer's disease.
ABSTRACT Retrospective epidemiologic studies suggest that individuals exposed to anti-inflammatory agents such as nonsteroidal anti-inflammatory drugs have a lower probability of developing AD as well as an older age at onset for the illness. Neuroinflammation may play an important role in the pathogenesis of AD. Interleukin 1 (IL-1), a potent proinflammatory cytokine, is colocalized immunohistochemically to neuritic plaques, a requisite neuropathologic feature for AD. A polymorphism in the 5'-flanking regulatory region at -889 of the IL-1 alpha gene (a C-to-T transition designated as IL-1A[-889] allele 2) may cause an overexpression of IL-1 alpha, a finding shown to be associated with inflammatory diseases. The IL-1A(-889) allele 2 polymorphism may be associated with AD pathogenesis.
A total of 259 patients with AD and 192 nondemented control subjects were included from two different centers (Indianapolis, IN, and Munich, Germany). Genotyping for APOE alleles and IL-1A(-889) allele 2 was performed by PCR-based amplification followed by restrictive endonuclease digestion. Statistical analyses were conducted by center-, gender group-, and age group-stratified Mantel-Haenszel odds ratios, CI, and p values.
The allele frequency of IL-1A(-889) allele 2 was 46% in clinically diagnosed patients with probable AD versus 34% in control subjects from the combined centers.
The authors found an increased risk for AD with an estimated Mantel-Haenszel odds ratio of 1.68 (95% CI 1.1 to 2.6; p = 0.022) for heterozygous carriers and 7.2 (95% CI 2.0 to 24.5; p = 0.003) for individuals homozygous for IL-1A(-889) allele 2. They found no evidence for an interaction between the IL-1A and the apoE epsilon 4 polymorphisms (carriers and homozygotes), age, or gender with regard to conferred risk. The data strongly support an association between the IL-1A(-889) allele 2, especially in homozygotes, and later-onset AD.
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ABSTRACT: Introduction Allergic reaction to dust mites is a relatively common condition among children, triggering cutaneous and respiratory responses that have a great impact on the health of this population. Anaphylactic hypersensitivity is characterized by an exacerbated response involving the production of regulatory cytokines responsible for stimulating the production of IgE antibodies. Objective To investigate an association of variants in cytokine genes (IL1A−889, IL1B−511, +3962, IL1R1970, IL1RA11100, IL4RA+1902, IL12−1188, IFNG+874, TGFB1codon 10, codon 25, TNFA−308, −238, IL2−330, +166, IL4−1098, −590, −33, IL6−174, nt565, and IL10−1082, −819, −592) between patients sensitive to dust mites and a control group. Methods A total of 254 patients were grouped as atopic and non-atopic according to sensitivity as evaluated by the Prick Test and to cytokine genotyping by the polymerase chain reaction-sequence specific primers (PCR-SSP) method using the Cytokine Genotyping Kit. Results A comparison between individuals allergic to Dermatophagoides farinae, Dermatophagoides pteronyssinus, and Blomia tropicalis and a non-atopic control group showed significant differences between allele and genotype frequencies in the regulatory regions of cytokine genes, with important evidence for IL4−590 in T/C (10.2% vs. 43.1%, odd ratio [OR] = 0.15, p = 5.2 10−8, pc = 0.0000011, and 95% confidence interval [95%CI] = 0.07–0.32) and T/T genotypes (42.9% vs. 13.8%, OR = 4.69, p = 2.5 10−6, pc = 0.000055, and 95%CI = 2.42–9.09). Other associations were observed in the pro-inflammatory cytokines IL1A−889 (T/T, C, and T) and IL2−330 (G/T and T/T) and the anti-inflammatory cytokines IL4RA+1902 (A and G), IL4−590 (T/C, T/T, C, and T), and IL10−592 (A/A, C/A, A, and C). Conclusion Our results suggest a possible association between single nucleotide polymorphisms (SNPs) in cytokine genes and hypersensitivity to dust mites.PLoS ONE 09/2014; 9(9):e107921. DOI:10.1371/journal.pone.0107921 · 3.53 Impact Factor
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ABSTRACT: To examine whether the IL-1A (-889) polymorphism associates with a risk for Alzheimer's disease (AD) and acts interactively with the apolipoprotein (APOE) 4 in the development of AD, we performed genotype analyses of the IL-1A and the APOE of the 102 Korean AD patients and 200 Korean non-demented controls. We failed to detect a significant difference in genotypic and allelic frequencies of IL-1A between the AD group and control group. No overexpression of the IL-1A C/T genotype and IL-1A T allele was found when we analyzed the late-onset and early-onset patients, separately. There was no significant genetic interaction between IL-1A polymorphism and the APOE polymorphism. I n conclusion, the IL-1A polymorphism did not contribute to the development of AD independently or interactively with the APOE 4 allele in Koreans.01/2004; 2(2).