Related Experiment Video
Updated: Jun 21, 2025

A Phenotyping Regimen for Genetically Modified Mice Used to Study Genes Implicated in Human Diseases of Aging
Published on: July 14, 2016
Caffeine Consumption and Interaction with ADORA2A, CYP1A2 and NOS1 Variants Do Not Influence Age at Onset of
Ana Carolina Martins1,2, Jordânia Dos Santos Pinheiro2,3, Luciana Szinwelski2,3
1Programa de Pós-Graduação em Genética e Biologia Molecular, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves 9500, Porto Alegre, 91501-970, Brazil.
Background:
The age at onset (AO) of Machado-Joseph disease (SCA3/MJD), a disorder due to an expanded CAG repeat (CAGexp) in ATXN3, is quite variable and the role of environmental factors is still unknown. Caffeine was associated with protective effects against other neurodegenerative diseases, and against SCA3/MJD in transgenic mouse models. We aimed to evaluate whether caffeine consumption and its interaction with variants of caffeine signaling/metabolization genes impact the AO of this disease.
Methods:
a questionnaire on caffeine consumption was applied to adult patients and unrelated controls living in Rio Grande do Sul, Brazil. AO and CAGexp were previously determined. SNPs rs5751876 (ADORA2A), rs2298383 (ADORA2A), rs762551 (CYP1A2) and rs478597 (NOS1) were genotyped. AO of subgroups were compared, adjusting the CAGexp to 75 repeats (p < 0.05).
Results:
171/179 cases and 98/100 controls consumed caffeine. Cases with high and low caffeine consumption (more or less than 314.5 mg of caffeine/day) had mean (SD) AO of 35.05 (11.44) and 35.43 (10.08) years (p = 0.40). The mean (SD) AO of the subgroups produced by the presence or absence of caffeine-enhancing alleles in ADORA2A (T allele at rs5751876 and rs2298383), CYP1A2 (C allele) and NOS1 (C allele) were all similar (p between 0.069 and 0.516).
Discussion:
Caffeine consumption was not related to changes in the AO of SCA3/MJD, either alone or in interaction with protective genotypes at ADORA2A, CYP1A2 and NOS1.
Related Concept Videos
Adrenergic Agonists: Indirect-Acting Agents
One mechanism involves depleting stored catecholamines by displacing them from synaptic vesicles. These agents, known as "displacers," are transported into vesicles at the expense of noradrenaline. Examples include amphetamine and tyramine, which lack a catechol moiety, resulting in prolonged action, improved oral...
Drugs Affecting Neurotransmitter Release or Uptake
Drugs Affecting Neurotransmitter Synthesis
Chronopharmacokinetics: Circadian Rhythms and Influence on Drug Response
The time of drug administration is an important factor to consider, as it can influence the toxic dose of a drug. For example, a study conducted by Prins et al. in 1997 examined the effects of the timing of...
Factors Affecting Drug Response: Overview
Nonlinear Pharmacokinetics: Dependence of Elimination Half-Life and Dose Clearance
A study on guinea pigs examined the...

