Ameliorative effect and mechanism of curcumin on diabetes model rats with depression / 中国药房

ABSTRACT

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.