Rapid eye movement sleep behavior disorder (RBD) is currently considered as a prodromal stage of alphasynucleinopathies neurodegeneration. The update data suggested that over 80% patients with idiopathic RBD eventually developed neurodegenerative disease after a mean of 14 years interval from the onset of RBD. A series of potential biomarkers have been identified to predict the development of neurodegeneration in idiopathic RBD, including olfactory loss, color vision deficit, depression, mild cognitive impairment, excessive daytime sleepiness, dopamine dysfunction, and tonic electromyographic activity. Early recognition of the predictive markers of neurodegeneration in idiopathic RBD is essential for development of intervention or prevention strategies at the presymptomatic stage. Nonetheless, the current literature is lacking biomarkers that might reflect the alpha-synuclein neuropathology at the earliest stages. Future studies with large samples and systematic follow-up are needed to confirm more potential markers of neurodegeneration at its early stages.
alpha-Synuclein ; Biomarkers* ; Color Vision ; Depression ; Dopamine ; Follow-Up Studies ; Humans ; Mild Cognitive Impairment ; Neurodegenerative Diseases ; Parkinson Disease ; Prodromal Symptoms ; REM Sleep Behavior Disorder* ; Sleep, REM*

OBJECTIVETo assess the biological effects of the six-herb mixture Anti-Insomia Formula (AIF) extract using caffeine-induced insomnia Drosophila model and short-sleep mutants.

METHODSCaffeineinduced insomnia wild-type Drosophila and short-sleep mutant flies minisleep (mns) and Hyperkinetic(Y) (Hk(Y)) were used to assess the hypnotic effects of the AIF in vivo. The night time activity, the amount of night time sleep and the number of sleep bouts were determined using Drosophila activity monitoring system. Sleep was defined as any period of uninterrupted behavioral immobility (0 count per minute) lasting > 5 min. Night time sleep was calculated by summing up the sleep time in the dark period. Number of sleep bouts was calculated by counting the number of sleep episodes in the dark period.

RESULTSAIF at the dosage of 50 mg/mL, effectively attenuated caffeine-induced wakefulness (P<0.01) in wild-type Canton-S flies as indicated by the reduction of the sleep bouts, night time activities and increase of the amount of night time sleep. AIF also significantly reduced sleeping time of short-sleep Hk(Y) mutant flies (P<0.01). However, AIF did not produce similar effect in mns mutants.

CONCLUSIONAIF might be able to rescue the abnormal condition caused by mutated modulatory subunit of the tetrameric potassium channel, but not rescuing the abnormal nerve firing caused by Shaker gene mutation. This study provides the scientific evidence to support the use of AIF in Chinese medicine for promoting sleep quality in insomnia.

Animals ; Caffeine ; Chromatography, High Pressure Liquid ; Disease Models, Animal ; Drosophila melanogaster ; drug effects ; physiology ; Hypnotics and Sedatives ; pharmacology ; therapeutic use ; Mutation ; genetics ; Potassium Channels ; genetics ; Sleep ; drug effects ; Sleep Initiation and Maintenance Disorders ; drug therapy ; Wakefulness ; drug effects