ABSTRACT
Based on the CX3C chemokine ligand 1(CX3CL1)-CX3C chemokine receptor 1(CX3CR1) axis, this study explored the potential mechanism by which Zuogui Jiangtang Jieyu Formula(ZGJTJY) improved neuroinflammation and enhanced neuroprotective effect in a rat model of diabetes mellitus complicated with depression(DD). The DD rat model was established by feeding a high-fat diet combined with streptozotocin(STZ) intraperitoneal injection for four weeks and chronic unpredictable mild stress(CUMS) combined with isolated cage rearing for five weeks. The rats were divided into a control group, a model group, a positive control group, an inhibitor group, and a ZGJTJY group. The open field test and forced swimming test were used to assess the depression-like behaviors of the rats. Enzyme-linked immunosorbent assay(ELISA) was performed to measure the expression levels of the pro-inflammatory cytokines interleukin-1β(IL-1β) and tumor necrosis factor-α(TNF-α) in plasma. Immunofluorescence staining was used to detect the expression of ionized calcium-binding adapter molecule 1(Iba1), postsynaptic density protein-95(PSD95), and synapsin-1(SYN1) in the hippocampus. Hematoxylin-eosin(HE) staining, Nissl staining, and TdT-mediated dUTP nick end labeling(TUNEL) fluorescence staining were performed to assess hippocampal neuronal damage. Western blot was used to measure the expression levels of CX3CL1, CX3CR1, A2A adenosine receptor(A2AR), glutamate receptor 2A(NR2A), glutamate receptor 2B(NR2B), and brain-derived neurotrophic factor(BDNF) in the hippocampus. Compared with the model group, the ZGJTJY group showed improved depression-like behaviors in DD rats, enhanced neuroprotective effect, increased expression of PSD95, SYN1, and BDNF(P<0.01), and decreased expression of Iba1, IL-1β, and TNF-α(P<0.01), as well as the expression of CX3CL1, CX3CR1, A2AR, NR2A, and NR2B(P<0.01). These results suggest that ZGJTJY may exert its neuroprotective effect by inhibiting the CX3CL1-CX3CR1 axis and activation of hippocampal microglia, thereby improving neuroinflammation and abnormal activation of N-methyl-D-aspartate receptor(NMDAR) subunits, and ultimately enhancing the expression of synaptic-related proteins PSD95, SYN1, and BDNF in the hippocampus.
Subject(s)
Rats , Animals , Depression/drug therapy , Brain-Derived Neurotrophic Factor , Neuroprotective Agents , Tumor Necrosis Factor-alpha/metabolism , Neuroinflammatory Diseases , Diabetes Mellitus , Receptors, Glutamate , CX3C Chemokine Receptor 1/geneticsABSTRACT
Objective To investigate the regulating effects of Zuogui Jiangtang Jieyu Formula (ZJJF) on Bcl-2, Bax and Caspase-8 in hippocampus neuron damage in diabetes mellitus with depression (DD). Methods Hippocampal neurons from 18 d pregnant rats were primitively cultivated, and then combination of glucose and corticosterone was used to construct DD simulation environment. Cultivated hippocampal neurons were randomly divided into normal group, blank serum group, model group, positive medicine (metformin+fluoxetine) serum group and to-be-tested medicine (ZJJF) serum group. Normal group and model group were given same amount culture medium, while other group were given relevant amont of 10％ medicine serum or blank serum. After modeling intervention for 18 h,Hoechst staining was used to detect the apoptosis of hippocampal neurons. The expression of Bcl-2, Bax and Caspase-8 was detected by high content analysis. Results Compared with the control group, hippocampal neuron dendrites ruptured or decreased, neural network connection decreased, cells showed significant staining, broken, uneven distribution of light spots, the expression of Bcl-2 protein decreased significantly (P<0.05), but Bax and Caspase-8 were increased (P<0.05, P<0.01). Compared with the model group, hippocampal neurons in both positive medicine serum group and ZJJF serum group gradually recovered. Hoechst staining showed that the nuclei were significantly homogenized, local highlights were significantly reduced, Bcl-2 protein expression levels were significantly increased (P<0.05, P<0.01), while Bax and Caspase-8 were obviously down-regulated (P<0.05, P<0.01). Conclusion ZJJF has protective effects on hippocampal neurons in DD of model rats, and its mechanism is related to regulating the expression of Bcl-2, Bax and Caspase-8 in hippocampus neuron.
ABSTRACT
Objective To observe the effects of Zuogui Jiangtang Jieyu Formula (ZJJF) on the ability of learning and memory and the expressions of JNK, Bcl-2 and Bax in hippocampus in diabetic rats with depression; To explore the protective mechanism of hippocampal damage in diabetic rats with depression. Methods High-fat gavage combined with intravenous injection of STZ was used to establish the model of diabetic rats. 28 days of chronic stress was given continuously and diabetic rats complicated with depression were built successfully. Then rats were randomly divided into 6 groups, including normal, model, positive medicine, high-, medium-, and low-dose of ZJJF groups. After the last administration, Morris water maze was used to detect escape latency time;Western blot was used to disclose the protein expressions of JNK, Bcl-2 and Bax in rat hippocampaus;RT-PCR was used to test the gene expressions of JNK and Bcl-2 and Bax. Results Compared with the normal group, escape latency time in model rats was significant longer (P<0.01), the protein and gene expression of JNK and Bax in rat hippocampaus significantly increased, Bcl-2 was markedly decreased (P<0.05, P<0.01);Compared with the model group, escape latency time in positive medicine group and high-dose of ZJJF group was significant shorter (P<0.01), the protein and gene expressions of JNK and Bax significantly decreased, and Bcl-2 markedly increased (P<0.05, P<0.01). Conclusion ZJJF can significantly improve the ability of learning and memory in diabetic rats with depression, which might be associated with preventing neuronal apoptosis in hippocampus.
ABSTRACT
Objective: To investigate the effects of Zuogui Jiangtang Jieyu Formula (ZJJF) on protein expression of CoIV, ZO-1, and α-SMA in hippocampal blood-brain barrier (BBB) in diabetes mellitus (DM) rats with depression. Methods: DM rat model with depression was established by the combination of high-fat diet, injection of Streptozotocin (STZ, 38 mg/kg), and chronic stress. The model rats were randomly divided into five groups, DM with depression group, metformin (0.18 g/kg) + fluoxetine (1.8 mg/kg) group, high-, mid-, and low-dose (32.82, 16.41, and 8.20 g/kg) ZJJF groups (n = 10). After 4 weeks of administration, the morphological changes of BBB were observed under the electron microscope, the expression of CoIV, ZO-1, and α-SMA in rat hippocampul BBB was detected by immunocytochemistry. Results: Compared with the control group, the expression of ZO-1 and α-SMA in the model group was decreased (P < 0.05), and the expression of CoIV was increased (P < 0.05). Compared with the model group, the expression of ZO-1 and α-SMA in metformin + fluoxetine group and high-dose ZJJF group was increased (P < 0.05, 0.01), and the expression of CoIV was decreased (P < 0.05). Conclusion: ZJJF could repair the damage of BBB in DM rats with depression, and the mechanism may be related to the expression regulation of CoIV, ZO-1, and α-SMA.
ABSTRACT
ObjectiveTo observe the effect ofZuogui Jiangtang Jieyu Formula on the expressions of glutamate, NR2A and NR2B in hippocampus of diabetic rats with depression;To explore the mechanism of protective effect. Methods Diabetes with depression rat models were established and then were randomly divided into the model group, positive medicine group, high-, medium- and low-doseZuogui Jiangtang Jieyu Formula groups. Normal rats acted as normal group, 16 rats per group. After 28 days of administration, Open-field test was used to detect the behavior of the rats;glutamate content of hippocampus was detected by ELISA;the expressions of NR2A and NR2B in rat hippocampus were detected by immunofluorescence.Results Compared with normal group, automatic activity times of rats in model group decreased significantly (P<0.01);both glutamate content (P<0.01) and expressions of NR2A, NR2B (P<0.01) increased significantly. Compared with the model group, automatic activity times of rats in positive medicine group and high-doseZuogui Jiangtang Jieyu Formula group significantly increased (P<0.01);glutamate content dropped (P<0.01);expressions of NR2A and NR2B decreased (P<0.05).ConclusionZuogui Jiangtang Jieyu Formula can improve depressive behavior of diabetic rats with depression, which may be related to the regulation of glutamate content and expressions of NR2A and NR2B in hippocampus.