Figure 2.

Models for interplay of miRNA regulation, circadian rhythm, sleep homeostasis and neuroprotection. Common miRNAs which could regulate circadian rhythm, sleep homeostasis and redox states are represented. Sleep homeostasis is strongly connected to circadian rhythm. Disruption of circadian rhythm causes sleep disorder, and vice versa. Patients with neurodegenerative disease often complain of sleep deprivation. Moreover, sleep disorders can be an early symptom of neurodegenerative diseases. Several miRNAs that are altered with the circadian abnormalities, sleep disorders or neurodegenerative diseases are dysregulated in the brain and blood of disease-model animals or patients with neurodegenerative diseases. Taken together, these facts suggest that miRNAs have the potential to be biomarkers as well as therapeutics for these diseases.