Microarray analysis of stress-related gene expression in patients with Ménière's disease

We developed an original microarray carrying 1,467 cDNAs of stress-related genes for the assessment of stress responses. In this study, we used microarray analysis to assess the stress-related gene expression profiles in peripheral leukocytes in 2 patients with definite Ménière's disease. In the attack and active phases, mRNA expression levels of 57 genes and 163 genes were either up-regulated more than twofold or down-regulated by less than half in patient 1 and patient 2, respectively. Patient 1 had sporadic episodes of vertigo attack, while patient 2 had an intractable course with frequent vertigo attacks, suggesting that the magnitude of changes in gene expression is correlated with the severity of the disorder in Ménière's disease. The expression of a total of 26 genes commonly changed in both patients in the attack and active phases and returned to the baseline levels in the remission phase, suggesting the involvement of the distinct group of stress-related genes in the development of vertigo attacks in Ménière's disease. We then examined the effects of caloric stimulation on the stress-related gene expression profiles in peripheral leukocytes in 5 healthy volunteers. Although unilateral caloric stimulation with cold water caused acute vertigo with nystagmus, the expression profiles of stress-related genes did not significantly change after this experiment. This finding indicated that the up- or down-regulated genes in the attack and active phases in patients with Ménière's disease are not secondary to vertigo or vertigo-associated anxiety. All these findings suggested that the distinct group of stress-related genes contributed to the development of vertigo attacks of Ménière's disease and that stress-related gene expression profiles in peripheral leukocytes can be a predictive and therapeutic tool for episodic vertigo attacks in patients with Ménière's disease.