RESUMO
OBJECTIVE To study the ameliorative effect and potential mechanism of curcumin on diabetes model rats with depression based on cAMP response element binding protein （CREB）/brain-derived neurotrophic factor （BDNF） signaling pathway. METHODS The diabetes model rat with depression was established by high fat and high sugar diet+intraperitoneal injection of streptozotocin+chronic unpredictable stress-induced depression. The successfully modeled rats were randomly divided into model group， positive control group （0.18 g/kg metformin and 1.8 mg/kg fluoxetine， gavage）， curcumin low-dose and high-dose groups （30， 60 mg/kg， gavage） and curcumin high-dose+CREB inhibitor group [60 mg/kg curcumin （gavage）+5 mg/kg CREB inhibitor 666-15 （intraperitoneal injection）]， with 12 rats in each group. Another 12 healthy rats were selected as the normal group. Each group was given a corresponding intervention for 4 weeks， the fasting blood glucose level of rats was detected， and the depression of rats was assessed. The levels of corticosterone （CORT） and inflammatory factors [tumor necrosis factor-α （TNF-α）， interleukin- 1β （IL-1β）， IL-6] in serum， and the levels of norepinephrine （NE） and 5-hydroxytryptamine （5-HT） in hippocampal tissue were determined. The pathological changes and neuronal apoptosis were observed in the hippocampal tissue of rats in each group； the expression levels of CREB， BDNF mRNA and protein in hippocampal tissue were detected. RESULTS Compared with the normal group， the hippocampal tissue of rats in the model group was severely damaged， and neurons were scattered， while the fasting blood glucose， the forced swimming immobility time， the tail suspension immobility time， serum levels of CORT， TNF-α， IL-1β and IL-6， and neuron apoptosis indexes were all increased or prolonged significantly （P＜0.05）. The levels of NE and 5-HT， the number of surviving neurons， and the expression levels of CREB and BDNF mRNA and protein in hippocampal tissue were decreased significantly （P＜0.05）. Compared with the 的model group， the damage to hippocampal tissue was relieved in the positive control group and curcumin groups， while the above indexes were improved significantly （P＜0.05）. The improvement effect of curcumin high-dose group was better than that of curcumin low-dose group （P＜0.05）. CREB inhibitor could significantly reverse the ameliorative effect of high-dose curcumin on the model rats （P＜0.05）. CONCLUSIONS Curcumin can improve the depression of diabetes model rats with depression， and relieve neuronal damage and inflammatory response， the mechanism of which may be associated with activating CREB/BDNF signaling pathway.
RESUMO
ObjectiveTo explore the syndromes and mechanisms of depression induced by maternal separation （MS） combined with chronic restraint stress （RS） in mice. MethodOn postnatal day 0 （PD0）， the offspring mice were randomized into a blank group （NC） and a modeling group. The mouse model of depression was established by MS+RS for 21 days. After removal of female mice on PD21， the modeled mice were randomized into model， Wenyang， Jieyu， Wenyang Jieyu， and fluoxetine groups， with 15 mice in each group. The sucrose preference， tail suspension， and open field tests were carried out to evaluate the anxiety and depression-like behavior in mice. Enzyme-linked immunosorbent assay was used to measure the adrenocorticotrophic hormone （ACTH） and corticosterone （CORT） levels in mouse plasma. High performance liquid chromatography-electrochemical detector was used to determine the content of monoamine neurotransmitters in the hippocampus. Real-time fluorescence quantitative polymerase chain reaction was employed to determine the mRNA levels of genes in the 5-hydroxytryptamine （5-HT） system， hypothalamic-pituitary-adrenal （HPA） axis， and brain-derived neurotrophic factor （BDNF） signaling pathway in the hippocampus. Immunohistochemistry was employed to determine the expression levels of proteins in the 5-HT system and HPA axis in the hippocampus. The Simple Western system was used to determine the protein levels of BDNF and tyrosine kinase receptor B （TrkB） in the hippocampus. ResultCompared with the NC group， the model group exhibited depression-like behavior， which was significantly relieved by Wenyang Jieyu prescription and fluoxetine. Compared with the NC group， the model group showed elevated levels of CORT and ACTH in the plasma （P<0.01）， which， however， were lowered by Wenyang Jieyu prescription and fluoxetine （P<0.05， P<0.01）. Compared with the NC group， the model group showed inhibited expression of neurotransmitters in the hippocampus （P<0.05， P<0.01）， while Wenyang Jieyu prescription and fluoxetine restored the expression of neurotransmitters （P<0.05， P<0.01）. Compared with NC group， the model group showed inhibition of the 5-HTergic nerve and abnormal activation of the HPA axis， and Wenyang Jieyu prescription and fluoxetine regulated the abnormal state of the 5-HTergic nerve and HPA axis. Compared with NC group， the modeling down-regulated the mRNA and protein levels of BDNF and TrkB in the hippocampus （P<0.05， P<0.01）， which， however， were recovered in Wenyang， Jieyu， Wenyang Jieyu， and fluoxetine groups （P<0.05， P<0.01）. ConclusionThe mouse model of depression induced by MS+RS may present the syndrome of Yang deficiency and liver depression. Wenyang Jieyu prescription may increase the content of hippocampal neurotransmitters by regulating the 5-HT system and the BDNF signaling pathway mediated by the HPA axis， thereby alleviating depression-like behavior in mice.
RESUMO
Objective: To investigate the antidepressant mechanism of supercritical CO2 extract from Compound Chaigui Precription from the perspective of cAMP signaling pathway. Methods: The rats model were established by chronic unpredictable mild stress (CUMS). The rats were administrated with high, medium and low doses of supercritical CO2 extract from Compound Chaigui Precription and venlafaxine as intervention drugs. The protein expression levels of cAMP, PKA, p-CREB and BDNF in tissues and their corresponding mRNA levels were explored for their antidepressant mechanism. Results: Compared with the blank group, the expression levels of cAMP, PKA, p-CREB and BDNF in the hippocampus of the model group were significantly decreased (P < 0.05, P < 0.01). After the intervention of the Compound Chaigui Precription, compared with the model group, there was a significant difference in the callus of each dose group. At the same time, the mRNA levels of TrkB, PKA, p-CREB and BDNF in the hippocampus of the model group were significantly decreased (P < 0.05, P < 0.01). After the intervention, there was a callback in each dose group compared with the model group, with significant differences. Conclusion: Supercritical CO2 extract from Compound Chaigui Precription can exert antidepressant effect by regulating cAMP-PKA-CREB-BDNF signaling pathway.