ABSTRACT
ObjectiveTo explore the potential mechanism of Zuogui Jiangtang Jieyu Formula （左归降糖解郁方， ZJJF） for diabetic rats with depression. MethodsSixty rats were randomly divided into normal group， model group， wingless MMTV integration site family member 5a （Wnt5a） agonist group， ZJJF group， and ZJJF plus Wnt5a inhibitor group， with 12 rats in each group. Except for the normal group， the rats were fed with high-fat chow， streptozotocin injection， and chronic mild unpredictable stress combination， to establish model of diabetes mellitus complicated with depression. After successful modelling， rats in the Wnt5a agonist group were given bilateral hippocampal stereotactic injections of Wnt5a agonist Foxy-5 with 5 μl each for 7 consecutive days； rats in ZJJF group were given 20.52 g/（kg·d） of ZJJF by gavage； rats in ZJJF plus Wnt5a inhibitor group were given the drug by gavage， and bilateral hippocampal stereotactic injections of Wnt5a inhibitors Box5， with the same dosage and injection method as above. The normal group and model group were given 10 ml/（kg·d） of normal saline by gavage. All groups were gavaged for 4 consecutive weeks. At the end of the intervention， the depression-like behaviour of rats was evaluated using the forced swimming experiment （immobility time） and the absent field experiment （number of activities）； the blood glucose and insulin levels of rats were measured and the insulin resistance index was calculated； the dendritic morphology of dentate gyrus neurons in the hippocampus was observed using Golgi staining； the level of dentate gyrus neuron proliferation was measured using 5-bromodeoxyuracil nucleoside （Brdu） injection and immunofluorescence； RT-qPCR and Western blot were used to detect the mRNA and protein expression of Wnt5a， Ras homologue genomic member A （RhoA） and Rho homologue-associated coiled-coil protein kinase 1 （ROCK1） in the dentate gyrus. ResultsCompared with the normal group， rats in the model group had significantly higher blood glucose， insulin and insulin resistance indices， longer immobility time， fewer activities， lower Brdu integral optical density values and Wnt5a， RhoA， ROCK1 protein and mRNA expression in the dentate gyrus of the hippocampus （P＜0.05 or P＜ 0.01）； the dendritic branches of rat hippocampal dentate gyrus neurons could be seen to be significantly reduced or broken， and their length shortened. Compared with the model group， the blood glucose， insulin and insulin resistance indices of rats in ZJJF group and the ZJJF plus Wnt5a inhibitor group significantly reduced （P＜0.05 or P＜0.01）； the immobility time of rats in the Wnt5a agonist group and ZJJF group was significantly shortened， the number of activities increased， the Brdu integral optical density values elevated， and the Wnt5a， RhoA， ROCK1 protein and mRNA expression elevated （P＜0.05 or P＜0.01）， and the number of dendritic branches of hippocampal dentate gyrus neurons significantly increased， the length lengthened， and the complexity of dendrites increased. Compared with the Wnt5a agonist group， rats in the ZJJF group showed significant decrease in blood glucose， insulin and insulin resistance indices， prolongation of immobilisation time， reduction in the number of activities， and reduction in the Brdu integral optical density value； except for the Wnt5a mRNA in ZJJF group， Wnt5a， RhoA， ROCK1 protein and mRNA expression reduced in both ZJJF group and ZJJF plus Wnt5a inhibitor group （P＜0.05 or P＜0.01）. Compared with ZJJF group， Wnt5a， RhoA， ROCK1 protein and mRNA expression were reduced in ZJJF plus Wnt5a inhibitor group （P＜0.05 or P＜0.01）. ConclusionZJJF can improve hyperglycemia and depressive-like behaviours in rat models of diabetes with depression， and its antidepressant effects may be related to the activation of hippocampal Wnt5a/RhoA signaling and promotion of dentate gyrus neuron dendritic growth.
ABSTRACT
Objective To observe the protective effect of modified Baishile Decoction on hippocampal neuronal cells cultured in vitro;To explore its mechanism of treating post-stroke depression.Methods Hippocampal neuronal cells from mammary rats were isolated and cultured in vitro,cell injury was induced by oxygen glucose deprivation combined with lipopolysaccharide.The cells were divided into normal group,model group,blank serum group(10%)and modified Baishile Decoction containing serum group(10%).Invertedmicroscope was used to observe cell morphological changes,CCK-8 method was used to detect cell survival rate,Hoechst33342 staining was used to observe apoptosis,ELISA was used to detect Glu,5-HT,TNF-α,IL-1β,and IL-6 contents in cell supernatant,the expressions of purinergic P2X7 receptor(P2X7R)and NOD-like receptor protein 3(NLRP3)were detected by immunofluorescence staining.Results Compared with the normal group,the hippocampal neurons in the model group showed significant changes in cell morphology,the cell survival rate significantly decreased(P<0.01),the cell apoptosis increased(P<0.01);Glu,TNF-α,IL-1β,IL-6 contents in cell supernatant significantly increased(P<0.05,P<0.01),5-HT content significantly decreased(P<0.01),P2X7R and NLRP3 expressions in hippocampal neuronal cells significantly increased(P<0.01).Compared with the model group,the morphology of hippocampal neurons in modified Baishile Decoction containing serum group was significantly improved,the cell survival rate significantly increased(P<0.01),the cell apoptosis reduced(P<0.01);Glu,TNF-α and IL-1β content in cell supernatant significantly reduced(P<0.05,P<0.01),5-HT content significantly increased(P<0.01),and P2X7R and NLRP3 expressions in hippocampal neuronal cells significantly decreased(P<0.01).Conclusion Modified Baishile Decoction may exert a protective effect on oxidative glucose deprivation combined with lipopolysaccharide induced hippocampal neuronal inflammation damage by inhibiting the P2X7R/NLRP3 signaling pathway,regulating neurotransmitter secretion,and inhibiting inflammatory factor release,thus treating post-stroke depression.
ABSTRACT
OBJECTIVE@#To investigate the effect of Zuogui Jiangtang Jieyu Decoction (ZJJ) on Shh signaling and self-renewal of neural stem cells in the hippocampal dentate gyrus of diabetic rats with depression.@*METHODS@#Diabetic rat models with depression were randomly divided into model group, positive drug (metformin + fluoxetine) group, and low-, medium-, and high-dose ZJJ groups (n=16), with normal SD rats as the control group. The positive drugs and ZJJ were administered by gavage, and the rats in the control and model groups were given distilled water. After the treatment, blood glucose level was detected using test strips, and behavioral changes of the rats were assessed by forced swimming test and water maze test. ELISA was used to examine the serum level of leptin; The expressions of nestin and Brdu proteins in the dentate gyrus of the rats were detected using immunofluorescence assay, and the expressions of self-renewal marker proteins and Shh signaling proteins were detected using Western blotting.@*RESULTS@#The diabetic rats with depression showed significantly increased levels of blood glucose and leptin (P < 0.01) and prolonged immobility time in forced swimming test (P < 0.01) and increased stage climbing time with reduced stage seeking time and stage crossings in water maze test (P < 0.01). The expressions of nestin and Brdu in the dentate gyrus, the expressions of cyclin D1, SOX2, Shh, Ptch1, Smo in the hippocampus and the nuclear expression of Gli-1 were decreased (P < 0.01) while hippocampal Gli-3 expression was increased significantly (P < 0.01) in the rat models. Treatment of rat models with high-dose ZJJ significantly reduced the blood glucose (P < 0.01) and leptin level (P < 0.05) and improved their performance in behavioral tests (P < 0.01). The treatment also obviously increased the expressions of nestin, Brdu, cyclin D1, SOX2, Shh, Ptch1, and Smo and the nuclear expression of Gli-1 in the dentate gyrus (P < 0.01) and reduced hippocampal expression of Gli-3 (P < 0.05) in the rat models.@*CONCLUSION@#ZJJ can significantly improve the self-renewal ability of neural stem cells and activate Shh signaling in dentate gyrus of diabetic rats with depression.