Anmeidan Modulates Circadian Rhythm of Spontaneous Activity and Influences Clock Proteins in Sleep-deprived Rats / 中国实验方剂学杂志

ABSTRACT

ObjectiveTo investigate the effect of Anmeidan （AMD） on biological rhythm and related protein expression in sleep-deprived rats. MethodA total of 80 SD rats were randomized into control group （Ctrl， equivalent volume of saline）， model group （SD， equivalent volume of saline）， AMD group （9.09 g·kg-1·d-1）， and melatonin group （MT， 0.27 g·kg-1·d-1）. Insomnia was induced in rats by self-made sleep deprivation box （4 weeks）. Circadian rhythm of spontaneous activity was evaluated by spontaneous activity video analysis system. Morphology of hypothalamus was observed based on hematoxylin-eosin （HE） staining， and the histomorphology of hypothalamus neurons and the Nissl's bodies based on Nissl staining. Western blotting was employed to detect the expression of hypothalamic proteins in cAMP-response element binding protein （CREB）/clock gene period （Per） pathway， and immunohistochemistry the expression of brain and muscle ARNT-like protein 1 （Bmal1）， Clock， Per1， and cryptochrome circadian regulator 1 （Cry1）. ResultThe model group demonstrated circadian rhythm disorder， as manifested by the significant increase in activity time in 6 designated time periods compared with the control group， and the rise in the activity speed and frequency （P<0.01）. Moreover， model group showed decrease in number of neurons which were sparsely arranged with shrunken or fragmented nuclei， reduction in number and loss of Nissl's bodies with light color， and drop in the relative expression of p-CREB and Per1， and the positive rate of Bmal1， Clock， Per1， and Cry1 （P<0.01）. Compared with model group， AMD group demonstrated reduction in time， speed， and frequency of activity （P<0.01）. Moreover， the AMD group also showed alleviation of neuronal damage （P<0.01）， and increase in the number of neurons with clear nuclei and cytoplasm in some， and the number of Nissl's bodies. AMD raised the expression of p-CREB and Per1 proteins， and the positive rate of Bmal1， Clock， Per1， and Cry1 （P<0.01）. ConclusionAMD ameliorated spontaneous circadian rhythm of sleep-deprived rats by regulating CREB/Per signaling pathway and further increasing the expression of Bmal1， Clock， Per1， and Cry1.