Profiling mRNA encoding glucocorticoid receptor alpha in saliva: Relationship to hair cortisol levels in individuals aged 15-25 years.

OBJECTIVE: We assessed levels of mRNA encoding two glucocorticoid receptor (GR) isoforms (GRalpha and GRbeta) in saliva and examined their relationship with hair cortisol levels and dental caries experience. DESIGN: Adolescents and young adults were assessed for dental caries experience, and hair cortisol was measured by ELISA. RNA was extracted from whole saliva using TRIzol, followed by quantitative real-time PCR analysis of GRalpha, GRbeta, and glyceraldehyde 3-phosphate dehydrogenase (GAPDH). RESULTS: GRbeta mRNA was not detectable in most samples, whereas GRalpha mRNA was observed in all samples. There were significantly lower levels of GRalpha mRNA in individuals with elevated hair cortisol levels than in those with normal cortisol levels. Levels of GRalpha mRNA did not differ significantly in individuals with dental caries experience compared to individuals with no caries experience. CONCLUSIONS: We identified and quantified mRNA encoding GRalpha in saliva. Its levels were inversely associated with hair cortisol (a marker of chronic stress). Although caries experience was associated with hair cortisol levels, there was no significant association between GRalpha levels and caries experience. Chronic stress has been proposed to be associated with reduced expression of GRalpha and this association appears to hold for GRalpha mRNA levels in saliva.