To investigate the antidepressant mechanism of Shenling Kaixin Granules(SLKX) in treating chronic unpredictable mild stress(CUMS) model rats. Ninety male SD rats were randomly divided into control group, model group, Shugan Jieyu Capsules(110 mg·kg~(-1)) group and SLKX low-(90 mg·kg~(-1)), medium-(180 mg·kg~(-1)), and high-dose(360 mg·kg~(-1)) groups. Depression rat model was replicated by CUMS method. After treatment, the behavioral changes of rats were evaluated by sugar preference, open field, elevated cross maze and forced swimming experiments. The contents of interleukin 1 beta(IL-1β), tumor necrosis factor α(TNF-α), brain-derived neurotrophic factor(BDNF) and 5-hydroxytryptamine(5-HT) in serum were determined by enzyme linked immunosorbent assay(ELISA), and the activities of superoxide dismutase(SOD) and catalase(CAT) in hippocampal CA1 region were also detected. Pathological changes in hippocampal CA1 region were detected by hematoxylin-eosin(HE) staining, and Western blot was used to determine the expression of nerve growth factor(NGF), BDNF, phospho-tyrosine kinase receptor(p-TrkB)/TrkB, phospho-cAMP-response element binding protein(p-CREB)/CREB, nuclear factor E2 related factor 2(Nrf2), heme oxygenase 1(HO-1), B-cell lymphoma-2(Bcl-2)/Bcl-2 associated X protein(Bax) and caspase-3 in hippocampal CA1 region. RESULTS:: showed that compared with the control group, the model group had decreased sugar preference, reduced number of entries and time spent in the center of open field and shortened total distance of movement, reduced number of entries and proportion of time spent in open arm, and increased number and time of immobility in forced swimming experiment. Additionally, the serum contents of IL-1β and TNF-α and the expression of caspase-3 were higher, while the contents of BDNF and 5-HT, the activities of SOD and CAT in hippocampal CA1 region, the expressions of NGF, BDNF, p-TrkB/TrkB, p-CREB/CREB, HO-1 and Bcl-2/Bax, and the Nrf2 nuclear translocation were lower in model group than in control group. Compared with the conditions in model group, the sugar preference, the number of entries and time spent in the center of open, total distance of movement, and the number of entries and proportion of time spent in open arm in treatment groups were increased while the number and time of immobility in forced swimming experiment were decreased; the serum contents of IL-1β and TNF-α and the expression of caspase-3 were down regulated, while the contents of BDNF and 5-HT, the activities of SOD and CAT in hippocampal CA1 region, the expressions of NGF, BDNF, p-TrkB/TrkB, p-CREB/CREB, HO-1, Bcl-2/Bax, and Nrf2 nuclear translocation were enhanced. In conclusion, SLKX might regulate the Nrf2 nucleus translocation by activating BDNF/TrkB/CREB pathway, lower oxidative stress damage in hippocampus, inhibit caspase-3 activity, and reduce apoptosis of hippocampal nerve cells, thereby playing an antidepressant role.
Rats ; Male ; Animals ; bcl-2-Associated X Protein/metabolism* ; Caspase 3/metabolism* ; Nerve Growth Factor/metabolism* ; Brain-Derived Neurotrophic Factor/metabolism* ; Signal Transduction ; Tumor Necrosis Factor-alpha/metabolism* ; Serotonin/metabolism* ; NF-E2-Related Factor 2/metabolism* ; Rats, Sprague-Dawley ; Antidepressive Agents/pharmacology* ; Hippocampus/metabolism* ; Superoxide Dismutase/metabolism* ; Sugars/pharmacology* ; Depression/genetics* ; Stress, Psychological/metabolism*

Objective To investigate the protective effect of resveratrol (RSV) on improving cognitive function in severely burned rats and its possible mechanism. Methods 18 male SD rats aged 18-20 months were randomly divided into 3 groups: control group, model group and RSV group, with 6 rats in each group. After successful modeling, the rats in RSV group were gavaged once daily with RSV (20 mg/kg). Meanwhile, the rats in control group and model group were gavaged once daily with an equal volume of sodium chloride solution. After 4 weeks, the cognitive function of all rats was estimated by Step-down Test. The concentration of tumor necrosis factor α (TNF-α) and interleukin 6 (IL-6) protein in serum of rats were detected by ELISA. The expression of IL-6, TNF-α mRNA and protein were estimated by real-time PCR and Western blotting. The apoptosis of hippocampal neurons was tested by terminal deoxynuclectidyl transferase-mediated dUTP-biotin nick end labeling assay (TUNEL). The expression of nuclear transcription factor-κB (NF-κB)/c-Jun N-terminal kinase (JNK) pathway-related proteins in hippocampus were assessed by Western blotting. Results Compared with the rats in model group, rats in RSV group exhibited improved cognitive function. Consistently, the rats in RSV group had a reduced concentration of TNF-α and IL-6 in serum, decreased mRNA and protein expressions of TNF-α and IL-6 in hippocampus, and decreased apoptosis rate and relative expression of p-NF-κB p65/NF-κB p65 and p-JNK/JNK in hippocampal neurons. Conclusion RSV alleviates inflammatory response and hippocampal neuronal apoptosis by inhibiting NF-κB/JNK pathway, thereby improving cognitive function in severely burned rats.
Resveratrol/pharmacology* ; Male ; Animals ; Rats ; Rats, Sprague-Dawley ; Burns/drug therapy* ; Cognition/drug effects* ; Hippocampus/metabolism* ; MAP Kinase Signaling System ; NF-kappa B/metabolism* ; Tumor Necrosis Factor-alpha/blood* ; Interleukin-6/blood* ; Neurons/drug effects* ; Apoptosis

Objective To investigate the effects of formononetin (FMN) on cognitive behavior and inflammation in aging rats with chronic unpredictable mild stress (CUMS). Methods SD rats aged about 70 weeks were divided into healthy control group, CUMS model group, CUMS combined with 10 mg/kg FMN group, CUMS combined with 20 mg/kg FMN group and CUMS combined with 1.8 mg/kg fluoxetine hydrochloride (Flu) group. Except for healthy control group, other groups were stimulated with CUMS and administered drugs for 28 days. Sugar water preference, forced swimming experiment and open field experiment were used to observe the emotional behavior of rats in each group. HE staining was used to observe the pathological injury degree of brain equine area. The contents of 5-hydroxytryptamine (5-HT) and 5-hydroxyindoleacetic acid (5-HIAA) were detected by the kit. The apoptosis was tested by terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) in the brain tissue. The levels of tumor necrosis factor α (TNF-α), inducible nitric oxide synthase (iNOS) and interleukin 6 (IL-6) in peripheral blood were measured by ELISA. Western blot analysis was used to detect Bcl2, Bcl2 associated X protein (BAX), cleaved caspase-9, cleaved caspase-3, Toll-like receptor 4 (TLR4), myeloid differentiation factor 88 (MyD88), and phosphorylated nuclear factor κB p65 (p-NF-κB p65) in brain tissues. Results Compared with CUMS model group, sugar water consumption, open field activity time, open field travel distance and swimming activity time significantly increased in the CUMS combined with 20 mg/kg FMN group and the CUMS combined with 1.8 mg/kg Flu group. The number of new outarm entry increased significantly, while the number of initial arm entry and other arm entry decreased significantly. The pathological damage of brain equine area was alleviated, and the contents of 5-HT and 5-HIAA were significantly increased. The ratio of BAX/Bcl2 and the expression of cleaved caspase-9 and cleaved caspase-3 protein as well as the number of apoptotic cells were significantly decreased. The contents of TNF-α, iNOS and IL-6 were significantly decreased. The protein levels of TLR4, MyD88 and p-NF-κB p65 were significantly decreased. Conclusion FMN can inhibit the release of inflammatory factors by blocking NF-κB pathway and improve cognitive and behavioral ability of CUMS aged rats.
Rats ; Animals ; Horses ; NF-kappa B/metabolism* ; Signal Transduction ; bcl-2-Associated X Protein/metabolism* ; Toll-Like Receptor 4/metabolism* ; Caspase 3/metabolism* ; Caspase 9/metabolism* ; Interleukin-6/metabolism* ; Tumor Necrosis Factor-alpha/metabolism* ; Myeloid Differentiation Factor 88 ; Hydroxyindoleacetic Acid/pharmacology* ; Serotonin/metabolism* ; Rats, Sprague-Dawley ; Hippocampus/metabolism* ; Cognition

OBJECTIVE: To investigate whether meranzin hydrate (MH) can alleviate depression-like behavior and hypomotility similar to Chaihu Shugan Powder (CSP), and further explore the potential common mechanisms. METHODS: Totally 120 Spraque-Dawley rats were randomly divided into 5-8 groups including sham, vehicle, fluoxetine (20 mg/kg), mosapride (10 mg/kg), CSP (30 g/kg), MH (9.18 mg/kg), [D-Lys3]-GHRP-6 (Dlys, 0.5 mg/kg), and MH+Dlys groups by a random number table, 8 rats in each group. And 32 mice were randomly divided into wild-type, MH (18 mg/kg), growth hormone secretagogue receptor-knockout (GHSR-KO), and GHSR+MH groups, 8 mice in each group. The forced swimming test (FST), open field test (OFT), tail suspension test (TST), gastric emptying (GE) test, and intestinal transit (IT) test were used to assess antidepressant and prokinetic (AP) effects after drug single administration for 30 min with absorbable identification in rats and mice, respectively. The protein expression levels of brain-derived neurotrophic factor (BDNF) and phosphorylated mammalian target of rapamycin (p-mTOR) in the hippocampus of rats were evaluated by Western blot. The differences in functional brain changes were determined via 7.0 T functional magnetic resonance imaging-blood oxygen level-dependent (fMRI-BOLD). RESULTS: MH treatment improved depression-like behavior (FST, OFT) and hypomotility (GE, IT) in the acute forced swimming (FS) rats (all P<0.05), and the effects are similar to the parent formula CSP. The ghrelin antagonist [D-Lys3]-GHRP-6 inhibited the effect of MH on FST and GE (P<0.05). Similarly, MH treatment also alleviated depression-like behavior (FST, TST) in the wild-type mice, however, no effects were found in the GHSR KO mice. Additionally, administration of MH significantly stimulated BDNF and p-mTOR protein expressions in the hippocampus (both P<0.01), which were also prevented by [D-Lys3]-GHRP-6 (P<0.01). Besides, 3 main BOLD foci following acute FS rats implicated activity in hippocampus-thalamus-basal ganglia (HTB) circuits. The [D-Lys3]-GHRP-6 synchronously inhibited BOLD HTB foci. As expected, prokinetic mosapride only had effects on the thalamus and basal ganglia, but not on the hippocampus. Within the HTB, the hippocampus is implicated in depression and FD. CONCLUSIONS MH accounts for part of AP effects of parent formula CSP in acute FS rats, mainly via ghrelin-related shared regulation coupled to BOLD signals in brain areas. This novel functionally connection of HTB following acute stress, treatment, and regulation highlights anti-depression unified theory.
Rats ; Mice ; Animals ; Brain-Derived Neurotrophic Factor/metabolism* ; Ghrelin/metabolism* ; Antidepressive Agents/therapeutic use* ; Hippocampus ; Stress, Psychological ; Mammals/metabolism*

OBJECTIVE: To investigate the role of hippocampal neurodevelopment in the antidepressant effect of baicalin. METHODS: Forty male Institute of Cancer Research mice were divided into control, corticosterone (CORT, 40 mg/kg), CORT+baicalin-L (25 mg/kg), CORT+baicalin-H (50 mg/kg), and CORT+fluoxetine (10 mg/kg) groups according to a random number table. An animal model of depression was established by chronic CORT exposure. Behavioral tests were used to assess the reliability of depression model and the antidepressant effect of baicalin. In addition, Nissl staining and immunofluorescence were used to evaluate the effect of baicalin on hippocampal neurodevelopment in mice. The protein and mRNA expression levels of neurodevelopment-related factors were detected by Western blot analysis and real-time polymerase chain reaction, respectively. RESULTS: Baicalin significantly ameliorated the depressive-like behavior of mice resulting from CORT exposure and promoted the development of dentate gyrus in hippocampus, thereby reversing the depressive-like pathological changes in hippocampal neurons caused by CORT neurotoxicity. Moreover, baicalin significantly decreased the protein and mRNA expression levels of glycogen synthase kinase 3β (GSK3β), and upregulated the expression levels of cell cycle protein D1, p-mammalian target of rapamycin (mTOR), doublecortin, and brain-derived neurotrophic factor (all P<0.01). There were no significant differences between baicalin and fluoxetine groups (P>0.05). CONCLUSION Baicalin can promote the development of hippocampal neurons via mTOR/GSK3β signaling pathway, thus protect mice against CORT-induced neurotoxicity and play an antidepressant role.
Male ; Animals ; Mice ; Corticosterone ; Fluoxetine/metabolism* ; Depression/chemically induced* ; Glycogen Synthase Kinase 3 beta/metabolism* ; Reproducibility of Results ; Antidepressive Agents/pharmacology* ; Hippocampus ; TOR Serine-Threonine Kinases/metabolism* ; RNA, Messenger/genetics* ; Behavior, Animal ; Disease Models, Animal ; Mammals/metabolism*

OBJECTIVE: To investigate the molecular mechanisms underlying the beneficial effect of electroacupuncture (EA) in experimental models of Alzheimer's disease (AD) in vivo. METHODS: Senescence-accelerated mouse prone 8 (SAMP8) mice were used as AD models and received EA at Yingxiang (LI 20, bilateral) and Yintang (GV 29) points for 20 days. For certain experiments, SAMP8 mice were injected intravenously with human fibrin (2 mg). The Morris water maze test was used to assess cognitive and memory abilities. The changes of tight junctions of blood-brain barrier (BBB) in mice were observed by transmission electron microscope. The expressions of fibrin, amyloid- β (Aβ), and ionized calcium-binding adapter molecule 1 (IBa-1) in mouse hippocampus (CA1/CA3) were detected by reverse transcription-quantitative polymerase chain reaction (qRT-PCR), Western blot or immunohistochemical staining. The expression of fibrin in mouse plasma was detected by enzyme-linked immunosorbent assay. The expressions of tight junction proteins zonula occludens-1 and claudin-5 in hippocampus were detected by qRT-PCR and immunofluorescence staining. Apoptosis of hippocampal neurons was detected by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) staining. RESULTS: Fibrin was time-dependently deposited in the hippocampus of SAMP8 mice and this was inhibited by EA treatment (P<0.05 or P<0.01). Furthermore, EA treatment suppressed the accumulation of Aβ in the hippocampus of SAMP8 mice (P<0.01), which was reversed by fibrin injection (P<0.05 or P<0.01). EA improved SAMP8 mice cognitive impairment and BBB permeability (P<0.05 or P<0.01). Moreover, EA decreased reactive oxygen species levels and neuroinflammation in the hippocampus of SAMP8 mice, which was reversed by fibrin injection (P<0.05 or P<0.01). Mechanistically, EA inhibited the promoting effect of fibrin on the high mobility group box protein 1 (HMGB1)/toll-like receptor 4 (TLR4) and receptor for advanced glycation end products (RAGE)/nicotinamide adenine dinucleotide phosphate (NADPH) signaling pathways (P<0.01). CONCLUSION EA may potentially improve cognitive impairment in AD via inhibition of fibrin/A β deposition and deactivation of the HMGB1/TLR4 and RAGE/NADPH signaling pathways.
Mice ; Humans ; Animals ; NADP/metabolism* ; Toll-Like Receptor 4 ; HMGB1 Protein/metabolism* ; Receptor for Advanced Glycation End Products/metabolism* ; Blood-Brain Barrier/metabolism* ; Neuroinflammatory Diseases ; Electroacupuncture ; Alzheimer Disease/therapy* ; Hippocampus/metabolism* ; Amyloid beta-Peptides/metabolism*

OBJECTIVE: To observe the effect of electroacupuncture (EA) at different frequencies on learning and memory functions, as well as the relevant proteins of brain insulin signal transduction pathway in Alzheimer's disease (AD) mice and explore the effect mechanism of EA in treatment of AD. METHODS: Seventy-two SPF Kunming male mice were randomized into a blank group, a sham-operation group, a model group, a 2 Hz EA group, a 15 Hz EA group and a 30 Hz EA group, 12 mice in each one. In the model group and each EA group, AD model were established by the injection with streptozotocin (ST2) solution (8 mg/kg) into the left lateral ventricles. In the sham-operation group, 0.9% sodium chloride solution of the same volume was injected into the left lateral ventricles. After successful modeling, in each EA group, EA was applied at "Baihui" (GV 20), "Dazhui" (GV 14) and "Shenshu" (BL 23) with corresponding frequencies, once daily. One course of EA intervention consisted of 7 treatments and 2 courses were given totally at interval of 1 day. After modeling and intervention, Morris water maze test was conducted for the mice of each group. Using immunohistochemistry and Western blot method, the protein expression of insulin receptor (IR), insulin receptor substrate-1 (IRS-1) and phosphatidylinositol 3-kinase (PI3K) was detected in the hippocampal of the mice after intervention. RESULTS: Compared with the blank group, in the model group, the 2 Hz, 15 Hz and 30 Hz EA groups, the escape latency and the first time of crossing the platform were all extended (P<0.01), and the number of crossing the platform was reduced (P<0.01) after modeling. When compared with the blank group, the escape latency and the first time of crossing the platform were all extended (P<0.01), and the number of crossing the platform was reduced (P<0.01) in the model group after intervention. In the 2 Hz, 15 Hz and 30 Hz EA groups, the escape latency and the first time of crossing the platform were all shortened (P<0.01), and the number of crossing the platform was increased (P<0.05, P<0.01) after intervention when compared with the model group. The escape latency and the first time of crossing the platform were all shortened (P<0.01, P<0.05), and the number of crossing the platform was increased (P<0.05) in the 15 Hz and 30 Hz EA groups in comparison with the 2 Hz EA group. The protein expression levels of IR, IRS-1 and PI3K were reduced in the model group when compared with those of the blank group (P<0.01, P<0.05); and these protein expression levels were increased in the 15 Hz and 30 Hz EA groups compared with the model group (P<0.05, P<0.01). Compared with the 2 Hz EA group, the protein expression levels of IR, IRS-1 and PI3K were all elevated in the 15 Hz and 30 Hz EA groups (P<0.05). CONCLUSION The learning and memory function of AD mice may be improved through regulating brain insulin signaling transconduction pathway with electroacupuncture, and electroacupuncture at 15 Hz and 30 Hz obtains the overall better effect compared with the intervention at 2 Hz.
Animals ; Male ; Mice ; Alzheimer Disease/therapy* ; Electroacupuncture ; Hippocampus/metabolism* ; Insulin/metabolism* ; Phosphatidylinositol 3-Kinases/metabolism* ; Signal Transduction

Malfunction of the ventral subiculum (vSub), the main subregion controlling the output connections from the hippocampus, is associated with major depressive disorder (MDD). Although the vSub receives cholinergic innervation from the medial septum and diagonal band of Broca (MSDB), whether and how the MSDB-to-vSub cholinergic circuit is involved in MDD is elusive. Here, we found that chronic unpredictable mild stress (CUMS) induced depression-like behaviors with hyperactivation of vSub neurons, measured by c-fos staining and whole-cell patch-clamp recording. By retrograde and anterograde tracing, we confirmed the dense MSDB cholinergic innervation of the vSub. In addition, transient restraint stress in CUMS increased the level of ACh in the vSub. Furthermore, chemogenetic stimulation of this MSDB-vSub innervation in ChAT-Cre mice induced hyperactivation of vSub pyramidal neurons along with depression-like behaviors; and local infusion of atropine, a muscarinic receptor antagonist, into the vSub attenuated the depression-like behaviors induced by chemogenetic stimulation of this pathway and CUMS. Together, these findings suggest that activating the MSDB-vSub cholinergic pathway induces hyperactivation of vSub pyramidal neurons and depression-like behaviors, revealing a novel circuit underlying vSub pyramidal neuronal hyperactivation and its associated depression.
Rats ; Mice ; Animals ; Rats, Sprague-Dawley ; Depressive Disorder, Major/metabolism* ; Basal Forebrain ; Depression ; Hippocampus/metabolism* ; Cholinergic Agents

Gene transcription and new protein synthesis regulated by epigenetics play integral roles in the formation of new memories. However, as an important part of epigenetics, the function of chromatin remodeling in learning and memory has been less studied. Here, we showed that SMARCA5 (SWI/SNF related, matrix-associated, actin-dependent regulator of chromatin, subfamily A, member 5), a critical chromatin remodeler, was responsible for hippocampus-dependent memory maintenance and neurogenesis. Using proteomics analysis, we found protein expression changes in the hippocampal dentate gyrus (DG) after the knockdown of SMARCA5 during contextual fear conditioning (CFC) memory maintenance in mice. Moreover, SMARCA5 was revealed to participate in CFC memory maintenance via modulating the proteins of metabolic pathways such as nucleoside diphosphate kinase-3 (NME3) and aminoacylase 1 (ACY1). This work is the first to describe the role of SMARCA5 in memory maintenance and to demonstrate the involvement of metabolic pathways regulated by SMARCA5 in learning and memory.
Mice ; Animals ; Memory ; Chromatin Assembly and Disassembly ; Hippocampus/metabolism* ; Transcription Factors/metabolism* ; Chromatin/metabolism* ; Metabolic Networks and Pathways

BACKGROUND: Posttraumatic stress disorder (PTSD) and depression are highly comorbid. Psilocybin exerts substantial therapeutic effects on depression by promoting neuroplasticity. Fear extinction is a key process in the mechanism of first-line exposure-based therapies for PTSD. We hypothesized that psilocybin would facilitate fear extinction by promoting hippocampal neuroplasticity. METHODS: First, we assessed the effects of psilocybin on percentage of freezing time in an auditory cued fear conditioning (FC) and fear extinction paradigm in mice. Psilocybin was administered 30 min before extinction training. Fear extinction testing was performed on the first day; fear extinction retrieval and fear renewal were tested on the sixth and seventh days, respectively. Furthermore, we verified the effect of psilocybin on hippocampal neuroplasticity using Golgi staining for the dendritic complexity and spine density, Western blotting for the protein levels of brain derived neurotrophic factor (BDNF) and mechanistic target of rapamycin (mTOR), and immunofluorescence staining for the numbers of doublecortin (DCX)- and bromodeoxyuridine (BrdU)-positive cells. RESULTS: A single dose of psilocybin (2.5 mg/kg, i.p.) reduced the increase in the percentage of freezing time induced by FC at 24 h, 6th day and 7th day after administration. In terms of structural neuroplasticity, psilocybin rescued the decrease in hippocampal dendritic complexity and spine density induced by FC; in terms of neuroplasticity related proteins, psilocybin rescued the decrease in the protein levels of hippocampal BDNF and mTOR induced by FC; in terms of neurogenesis, psilocybin rescued the decrease in the numbers of DCX- and BrdU-positive cells in the hippocampal dentate gyrus induced by FC. CONCLUSIONS A single dose of psilocybin facilitated rapid and sustained fear extinction; this effect might be partially mediated by the promotion of hippocampal neuroplasticity. This study indicates that psilocybin may be a useful adjunct to exposure-based therapies for PTSD and other mental disorders characterized by failure of fear extinction.
Humans ; Mice ; Animals ; Psilocybin/metabolism* ; Fear ; Extinction, Psychological ; Brain-Derived Neurotrophic Factor/metabolism* ; Bromodeoxyuridine/pharmacology* ; Hippocampus/metabolism* ; Neuronal Plasticity ; TOR Serine-Threonine Kinases/metabolism*