Human herpesvirus 6 and 7 are biomarkers for fatigue, which distinguish between physiological fatigue and pathological fatigue

• Published in: Biochemical and biophysical research communications 2016-09, Vol.478 (1), p.424-430
• Main Authors: Aoki, Ryo, Kobayashi, Nobuyuki, Suzuki, Go, Kuratsune, Hirohiko, Shimada, Kazuya, Oka, Naomi, Takahashi, Mayumi, Yamadera, Wataru, Iwashita, Masayuki, Tokuno, Shinichi, Nibuya, Masashi, Tanichi, Masaaki, Mukai, Yasuo, Mitani, Keiji, Kondo, Kazuhiro, Ito, Hiroshi, Nakayama, Kazuhiko
• Format: Article
• Language: English
• Subjects: Adult; Biomarkers; Chronic fatigue syndrome; Diagnosis, Differential; Fatigue; Fatigue Syndrome, Chronic - diagnosis; Fatigue Syndrome, Chronic - virology; Herpesviridae; Herpesvirus 6, Human - isolation & purification; Herpesvirus 7, Human - isolation & purification; HHV-6; HHV-7; Human herpesvirus 6; Human herpesvirus 7; Humans; Major depressive disorder; Male; Military Personnel; Obstructive sleep apnea syndrome; Reproducibility of Results; Saliva - virology; Sensitivity and Specificity; Viral Load - methods
• ISSN: 0006-291X; 1090-2104
• DOI: 10.1016/j.bbrc.2016.07.010

Fatigue reduces productivity and is a risk factor for lifestyle diseases and mental disorders. Everyone experiences physiological fatigue and recovers with rest. Pathological fatigue, however, greatly reduces quality of life and requires therapeutic interventions. It is therefore necessary to distinguish between the two but there has been no biomarker for this. We report on the measurement of salivary human herpesvirus (HHV-) 6 and HHV-7 as biomarkers for quantifying physiological fatigue. They increased with military training and work and rapidly decreased with rest. Our results suggested that macrophage activation and differentiation were necessary for virus reactivation. However, HHV-6 and HHV-7 did not increase in obstructive sleep apnea syndrome (OSAS), chronic fatigue syndrome (CFS) and major depressive disorder (MDD), which are thought to cause pathological fatigue. Thus, HHV-6 and HHV-7 would be useful biomarkers for distinguishing between physiological and pathological fatigue. Our findings suggest a fundamentally new approach to evaluating fatigue and preventing fatigue-related diseases. •Salivary HHV-6 and HHV-7 can be used for assessment of physiological fatigue.•Activation and differentiation of macrophages are needed for viral reactivation.•Salivary HHV-6 and HHV-7 do not increase with pathological fatigue.•Salivary HHV-6/7 can distinguish between physiological and pathological fatigue.