Abstract:
OBJECTIVE To explore the mechanism of Xiaoyaosan in improving the abnormal glucose metabolism in chronic sleep deprivation(CSD) mice based on tyrosine hydroxylase/alpha-2a adrenergic receptor(TH/ADRA2A) signal pathway.
METHODS Fifty six-week-old male C57BL/6 mice were randomly divided into two groups: 10 in the control group and 40 in the model group. The rats in the model group were deprived of sleep for 4 weeks by the method of multi-platform water environment. Fasting plasma glucose(FPG) and body mass were measured once a week for three consecutive weeks. Then, according to FPG, they were randomly divided into four groups, namely model group, guanethidine group(30 mg·kg
-1·d
-1) and Xiaoyaosan low and high dose groups(33.88, 101.64 g·kg
-1·d
-1). After grouping, continue modeling for a week. Then the drug was administered for 4 weeks. The control group and model group were treated with pure water of the same volume. Modeling continued during the administration period. On the 53rd day, blood was collected from the tail vein for the glucose tolerance test. On the 56th day, the expression of insulin(INS), noradrenaline(NE) and corticosterone(CORT) in serum was detected by ELISA. HE staining was used to observe the pathological changes of pancreatic islets. Detection of co expression of TH and INS in pancreatic tissues by immunofluorescence staining. Real-time PCR and Western blotting were used to detect the expression of ADRA2A mRNA and protein in the pancreas.
RESULTS In the process of CSD modeling, compared with the initial body mass, the body mass of the model group mice decreased significantly at the end of the first week of modeling(
P<0.05), and FPG increased significantly(
P<0.01). After administration, compared with the control group, the glucose tolerance of the model group was significantly abnormal. The levels of NE, CORT and INS increased significantly(
P<0.01), the expression level of ADRA2A mRNA and protein in the pancreas was significantly increased(
P<0.01). Compared with the model group, Xiaoyaosan groups had better glucose tolerance, the levels of NE, CORT and INS decreased significantly(
P<0.05), and the expression of ADRA2A mRNA and protein in the pancreas decreased significantly(
P<0.05 or
P<0.01). HE staining results showed that the number of cells in the islets of the model group was significantly reduced compared with the control group, and the situation was improved in all drug groups. The results of immunofluorescence staining showed that the protein content of TH in the model group increased, and the expression of TH in each group decreased after administration.
CONCLUSION Xiaoyaosan can improve the abnormal glucose metabolism induced by CSD, and its mechanism may be related to the reduction of TH/ADRA2A expression.