Biology Basis Of Liver Diversion Based On Chronic Unpredictable Mild Stress Rat Model

ObjectiveTo explore the biological basis of "Liver governs coursing" at the aspects of organ, protein and gene, from the two angles of anatomic liver and functional liver zang.MethodsThe study was divided into three parts:(1) A dynamic observation on the CUMS model. The indices of weight, sucrose preference test (SPT), open field test (OFT), liver ultrasound, resting-state BOLD were measured every two weeks to evaluate the change of depression degree, liver anatomical morphology and hemodynamics, brain neurons activity, by which to interpret the function of liver zang from a dynamic perspective. (2) The study on the biological basis of "depression with liver-qi stagnation and spleen deficiency syndrom", by which to elucidate the function of liver zang from the angle of related pathological model. The rats which were identified as the model of depression with liver-qi stagnation and spleen deficiency syndrome in the first experiment were selected. Accoring to the hypothesis of 973 subject, the methods of liver ultrasound, resting-state BOLD, ELISA, HPLC, digital gene expression profile, and PCR were applied to detect the changes of liver hemodynamics, abnormal brain neuron activity, chemical indicators (Hcy, AngⅡand 5-HT, NE, DA, Cort) in the blood, the hypothalamus neurotransmitters(NE, DOPAC, DA and 5-HIAA, 5-HT, HVA), and the differential expression genes in the liver and hippocampus. (3) The study on the molecular mechanism of Sini San’s antidepressant effect on the model of "depression with liver-qi stagnation and spleen deficiency syndrom", by which to elucidate the function of liver zang from the angle of liver-discharging effect. the same methods as that in the second study were applied to observe whether si-ni-san can improve the indices in the blood (Hcy, Ang Ⅱ and 5-HT, NE, DA, Cort), the hypothalamus neurotransmitters (NE, DOPAC, DA and 5-HIAA,5-HT, HVA), and the genes in the liver (Cyp1a1, Cypla2 Cyp7b1, Hnf4a, and Hnf4y) detected in the second study.Results(1)Since 2-week CUMS, the weight, sucrose preferenc and independent activity have been significantly decreased compared with normal group; The hepatic vein diameter was significantly higher than that of normal group when exposed to 8 week-CUMS. The hepatic venous blood flow velocity was significantly lower than that of normal group when exposed to 2 week-,4 week- and 6 week- CUMS. The hepatic vein blood flow was significantly lower than that in normal group when exposed to 6 week-CUMS. When exposed to 4 week-and 8 week-CUMS, the portal venous blood flow velocity was significantly decreased. The portal venous blood flow was significantly decreased when exposed to 8 week-CUMS; When exposed to 2 week-CUMS, compared with the normal group, the CUMS group demonstrate increased Reho in the cerebellum posterior lobe, increased ALFF in the olfactory bulb and decreased ALFF in the island cortex, olfactory cortex and sensory cortex. When exposed to 4 week-CUMS, compared with the normal group, the CUMS group demonstrate increased Reho in the hippocampus, olfactory cortex, sensory cortex and striatum, increased ALFF in the visual cortex and hippocampus. When exposed to 6 week-CUMS, compared with the normal group, the Reho in the hippocampus, lateral dorsal thalamus nucleus group decreased, the ALFF in the motor cortex, and the sensory cortex increased, and the ALFF in the dorsal thalamus of the lateral nuclear group, medulla oblongata, midbrain tegmentum, and base and tegment of pons decreased. When exposed to 8 week-CUMS, compared with the normal group, the Reho in the hippocampus, hypothalamus, nipple area, the midbrain tegmentum, olfactory cortex, piriform cortex, basal parts of pons decreased, and the ALFF in the cerebellar nuclei, the hypothalamus preoptic area, pons base decreased. (2) The model of "depression with liver-qi stagnation and spleen deficiency syndrom" demonstrated significantly decreased weight, sucrose preference, and independent activity; Both the volume and velocity of the portal venous blood flow were significantly reduced compared with the normal group; The result of BOLD was same as that in the second study(8-week CUMS); The contents of 5-HT,5-HIAA, DA in the hypothalamus were significantly decreased; The levels of Hcy and Cor in the blood were significantly higher than that of normal group, while NE content decreased significantly; A total of 46 in the liver and 85 in the hippocampus differentially expressed genes were detected. According to the enrichment of KEGG pathways, both of the most reliable pathways in the liver and hippocampus were involved in the cytochrome P450 family genes, which were vertificated by PCR. (3) Sini San could significantly improve the reduced number of rearings, while the total moved distance, sucrose preference and immobility time only performed improvement trend; Sini San could reduced the Ang Ⅱ level in the blood, compared with the model group; Sini San could significantly improve the 5-HT in the hypothalamus and show improve tendency on the level of 5-HI A A and DA; Positive correlations between the rearings and the content of 5-HI AA, 5-HT, DA in the hypothalamus, and the expression of Hnf4y in the liver were found. Besides, the content of 5-HIAA in the hypothalamus showed negative correlation with the immobility time and positive correlation with the total moved distance.Conclusions(1) Organ level:From the angle of dynamic and pathological model, it proved that the dysfunction of liver zang can influence the liver hemodynamics especially the portal venous hemodynamics. There are also neuron activity change in the limbic system especially the hippocampus and hypothalamus, and non limbic system including the cerebellum,?midbrain, sensory cortex, the visual cortex, motor cortex and so on; Protein level:From the angle of pathological model and liver-discharging, it proved that the content of 5-HT, DA in the hypothalamus, and the cort in the blood are the biological basis of "liver governs coursing"; Genetic level:Both the anatomic liver and functional liver zang(hipocammpus) exist the dysfunction of CYP450 family.(2) Sini San may improve the depressive behavior via adjust the hypothalamic neurotransmitter and liver Hnf4α、Hnf4y gene level, which indicated a possible relationship between the depression pathogenesis and liver change.(3)Both the anatomic liver and functional liver zang(hipocammpus) are the important biological basis of the liver zang.