Ruiguo Zhang

Free and Easy Wanderer Plus (FEWP), a polyherbal preparation, ameliorates PTSD-like behavior and cognitive impairments in stressed rats

Free and Easy Wanderer Plus (FEWP) is a well-known traditional Chinese medicine that has been shown to be effective in treating various mood disorders. The purpose of the present study was to determine whether FEWP could ameliorate stress-associated behavior in rats. Following the exposure to enhanced single prolonged stress (ESPS) paradigm, consisting of 2-hr constraint, 20-min forced swimming, ether-induced loss of consciousness, and an electric foot shock, animals were administered orally with FEWP (2.5, 5, or 10mg/kg daily) or vehicle for 2 weeks. Animals were then tested in the open field, elevated plus-maze, and Morris water maze. ESPS exposure resulted in pronounced anxiety-like behavior, without impairing locomotor activity, as indicated by significant decreases of time spent and number of entries into open arms in the elevated plus-maze test, and unaltered distance traveled in the open field test compared to unexposed animals. ESPS-exposed animals also displayed marked cognitive impairments, with significant increases of distance traveled and the escape latency to the underwater platform, and a striking decrease of time spent in the target quadrant with and without the removal of the platform in the water maze test. However, repeated treatment with FEWP, particularly at higher doses, reversed the aforementioned behavioral values in the elevated plus-maze and water maze tests to the levels similar to unexposed animals. These results indicate that FEWP possesses anxiolytic and cognition-improving effects and may be an effective herbal preparation for the treatment of stress-associated conditions, such as posttraumatic stress disorder (PTSD).

Psychopathological, biological, and neuroimaging characterization of posttraumatic stress disorder in survivors of a severe coalmining disaster in China

On July 29, 2007, a severe coalmine-flooded disaster occurred in central China and 69 miners were trapped in an about 1400 m underground coal pit. Fortunately, all of them were rescued after 75 h of the ordeal. At 3 and 6 months after the disaster, psychopathological profiles, plasma levels of cortisol and adrenocorticotropic hormone (ACTH) were evaluated in 48 survivors for posttraumatic stress disorder (PTSD) and comorbid symptoms. Magnetic resonance imaging (MRI) study was performed at 6 months. The prevalence of PTSD was 35.4% (17/48) at 3 months and 31.3% (15/48) at 6 months post-disaster, with high rates of comorbid symptoms. Risk factors for PTSD included previous traumatic experience, less than 5 years of being a miner, in an extremely exhausted or sick during the disaster, poor interpersonal relationship and poor sleep quality experienced before the disaster. Mean plasma cortisol levels at 6 months, but not at 3 months, were significantly higher in PTSD-positive subjects than the negative, and positively correlated with the severity of several comorbid symptoms. Either whole or regional brain volumes of PTSD-positive subjects were not significantly different from PTSD-negative subjects, but PTSD subjects had significantly reduced fractional anisotropy values in the right posterior cingulum and bilateral hippocampal body compared to subjects without PTSD. These results suggest that traumatic exposure in severe coalmining disasters results in considerable psychological consequences, with highly prevalent PTSD and comorbid symptoms, which are associated with previous traumatic experience, shorter-length underground services, and poor interpersonal relationships and sleep quality experienced before the disaster. Baseline cortisol level may be a useful biological predictor for different phases of the development of PTSD. The aberrant connectivity of the hippocampus and the cingulum may represent an early pathological response to trauma exposure.

Gastrodin ameliorates depression-like behaviors and up-regulates proliferation of hippocampal-derived neural stem cells in rats: Involvement of its anti-inflammatory action

Gastrodin (GAS), an active constituent of the Chinese herbal medicine tianma, has antidepressant-like activity in animals but no specific molecular mechanisms have been identified. In the present study, chronic unpredictable stress (CUS) was used to establish a rat depression model; The sucrose preference test, forced swim test and Morris water maze test were used to assess depression-like behaviors (anhedonia, behavioral despair, motor retardation, and poor spatial memory), and the proliferation of hippocampal stem cells was tested by BrdU immunohistochemistry. The stress and inflammatory responses were assayed by measuring IL-RA, NF-κB, and p-iκB expression by Western blot and IL-1β production by ELISA. Direct and indirect effects of GAS on NSC viable cell number were examined in vitro by WST-1 and BrdU assays. It was found that GAS (200 mg/kg daily) reversed all tested depression-like behaviors in CUS model rats and up-regulated NSCs proliferation in the hippocampus. Enhanced expression of p-iκB, NF-κB, and IL-1β by CUS was also reversed by GAS. Moreover, in vitro experiments revealed that GAS alone did not increase the viability of NSCs but protected them from IL-1β-induced damage. These results support the antidepressant and neuroprotective effects of GAS, and GAS may reduce depression-like behaviors by protecting hippocampal NSCs against the proinflammatory cytokine IL-1β.

Differential effects of classical and atypical antipsychotic drugs on rotenone-induced neurotoxicity in PC12 cells

Although classical and atypical antipsychotics may have different effects against neurotoxicity, the underlying mechanisms remain to be elucidated. In the present study, we compared the atypical agents, risperidone (RIP), olanzapine (OLZ), and quetiapine (QTP), with the classical agent haloperidol (HAL) in reducing cytotoxicity induced by rotenone, a mitochondrial complex I inhibitor, in PC12 cells. We also determined whether there were differential effects of RIP and HAL on the expression of brain-derived neurotrophic factor (BDNF), signal transducers and activators of transcription-3 (STAT-3), and the immediate early gene c-fos, as well as intracellular levels of calcium. Exposure to 6 muM rotenone for 24 h resulted in a significant decrease in cell viability and apoptotic alteration. The rotenone-induced cytotoxicity was dose-dependently worsened by pretreatment with HAL, but significantly improved by the aforementioned atypical agents at low doses. Real-time PCR analysis revealed that HAL pretreatment significantly increased BDNF mRNA expression but did not alter c-fos and STAT-3 expression compared to rotenone-exposed cells. Unlike HAL, RIP pretreatment produced a significant elevation of all the three substance mRNA expression and the expression intensity was 2.6- to 4.6-fold greater than HAL. Pretreatment with RIP, but not HAL, also effectively prevented an elevation of intracellular levels of calcium provoked by rotenone. These results suggest that the protective effects of atypical antipsychotics are associated with a greater capacity to enhance pro-cell survival factors, therapeutic biomarker expression, and blockade of calcium influx. This may provide an alternative for explaining therapeutic advantages of atypical agents observed in clinical use.

Anti-depressive mechanism of repetitive transcranial magnetic stimulation in rat: the role of the endocannabinoid system.

Repetitive transcranial magnetic stimulation (rTMS) to treat depression has been thoroughly investigated in recent years. However, the underlying mechanisms are not fully understood. In this study, a chronic unpredictable mild stress (CUMS) paradigm was applied to male Sprague Dawley rats. Then rTMS was performed for 7 consecutive days, and the anti-depressive effects were evaluated by the sucrose preference test (SPT), the forced swimming test (FST), and the open-field test (OFT). Hippocampal cannabinoid type I receptor (CB1) expression was measured, and the expression levels of brain-derived neurotrophic factor (BDNF), Bcl-2, and Bax and the number of bromodeoxyuridine (BrdU)-positive cells were also investigated. These parameters were also observed after the selective CB1 receptor antagonist AM251 was used as a blocking agent. The results showed that CUMS induced a significant decrease in sucrose preference, a significant increase in immobility time in the FST, and a significantly decreased horizontal distance in the OFT. In addition, reduced hippocampal CB1 receptor, BDNF, and Bcl-2/Bax protein expression levels in CUMS rats, as well as decreased cell proliferation were also observed in the dentate gyrus. Meanwhile, rTMS treatment up-regulated cell proliferation; elevated CB1 receptor, BDNF, and Bcl-2/Bax expression levels in the hippocampus; and ameliorated depressive-like behaviors. All of these beneficial effects were abolished by AM251. These results indicate that rTMS increases BDNF production and hippocampal cell proliferation to protect against CUMS-induced changes through its effect on CB1 receptors.

Ziprasidone ameliorates anxiety-like behaviors in a rat model of PTSD and up-regulates neurogenesis in the hippocampus and hippocampus-derived neural stem cells.

Ziprasidone, a widely used atypical antipsychotic drug, has been demonstrated to have therapeutic effects in patients with post-traumatic stress disorder (PTSD), but its underlying mechanisms remain poorly understood. One possible explanation is that the neuroprotective and neurogenetic actions of ziprasidone can attenuate the neuronal apoptosis which occurs in the hippocampus. To test this hypothesis, the present study was designed to assess the effects of ziprasidone treatment on anxiety-like behaviors, hippocampal neurogenesis, and in vivo/in vitro expression of pERK1/2 and Bcl-2 in male Sprague-Dawley rats. The methodology involved 3 different experiments, and the investigations also included the assessment of U0126 interference in ziprasidone treatment. It was found that the in vivo, administration of ziprasidone not only reversed the anxiety-like behaviors in rats that exposed to an enhanced single prolonged stress paradigm, but also restored the proliferation and the protein expression of pERK1/2 and Bcl-2 in the hippocampus of these rats. Also, mild concentrations of ziprasidone promoted the in vitro proliferation of hippocampal-derived neural stem cells (NSCs) and increased the levels of pERK1/2 and Bcl-2 in NSCs. Interestingly, the observed effects of ziprasidone were inhibited by U0126. These data support the use of ziprasidone for the treatment of PTSD and indicate that the changes in the ERK1/2 signaling cascade may play a critical role in the pathophysiology of PTSD and its treatment modalities. Further investigations are needed to elucidate the detailed signal cascades involved in the pathophysiology of stress-related disorders, and confirm the efficacy of ziprasidone in anti-PTSD treatment.

Microinjection of sanguinarine into the ventrolateral orbital cortex inhibits Mkp-1 and exerts an antidepressant-like effect in rats

We investigated the antidepressant effects of bilateral intra-the ventrolateral orbital cortex (VLO) administration of sanguinarine (SA), a selective mitogen-activated protein kinase phosphatase-1 (Mkp-1) inhibitor, in rats that had been subjected to a forced swimming test (FST) which is a classic animal model of depression. The expression of Mkp-1 and activation of ERK (ratio of phosphor-ERK to ERK) were also examined by immunoblotting. A single bilateral intra-VLO infusion of SA (2.5, 5 or 10 μg/0.5 μl per side) significantly reduced immobility time in the FST in dose-dependent fashion, as compared to vehicle-treated controls. A similar antidepressant effect was also observed in rats systemically administered fluoxetine, a classic antidepressant. The effects observed in the FST could not be attributed to non-specific increases in activity as neither microinjection of SA into the VLO nor fluoxetine treatment altered the behavior of the rats during the locomotion test. In addition, a decrease in the expression of Mkp-1 and a correlative increase in ERK activation were involved in the antidepressant effects of the bilateral SA administration into the VLO. The results indicated that Mkp-1 within the VLO is involved in the process of depression and may be a potential target for therapeutic action of antidepressant treatment.

Quetiapine add-on therapy improves the depressive behaviors and hippocampal neurogenesis in fluoxetine treatment resistant depressive rats

Quetiapine, an atypical antipsychotic, may have efficacy as augmentation therapy in treatment resistant depression (TRD), but evidence is limited and the underlying mechanism remains poorly understood. Therefore, this study was aimed to investigate whether and how quetiapine can be served as an augmentation agent in fluoxetine treatment resistant depressive rats induced by chronic unpredictable mild stress (CUMS). In this study, the effects of CUMS regimen and antidepressant treatment were assessed by behavioral tests and hippocampal neurogenesis. Approximately 20-30% of depressive rats respond poorly to fluoxetine treatment. In their hippocampus, a significant decrease of neurogenesis was also observed. However, quetiapine add-on therapy significantly improved the depressive behaviors and increased the number of the newborn neurons in the hippocampus of fluoxetine treatment resistant depressive rats. Thus, our results suggest that quetiapine may be used as an augmentation agent in the treatment resistant depression partly mediated by increasing the number of newborn neurons in the hippocampus.

Efficacy of repetitive transcranial magnetic stimulation in the prevention of relapse of depression: study protocol for a randomized controlled trial.

BackgroundDepression is a chronic illness that generally requires lifelong therapy. Repetitive transcranial magnetic stimulation (rTMS) is a noninvasive technique with few side effects that has been reported to be useful in the treatment of depression. However, no studies to date have evaluated in a randomized controlled trial (RCT) the efficacy of rTMS for maintenance treatment of depression.Methods/designIn this article, we report the design and protocol of a randomized, single-blind, placebo-controlled, parallel-group, multicenter study in China to evaluate the efficacy of rTMS in the prevention of relapse of depressive symptoms. In total, 540 patients, aged 18 to 60 years, diagnosed with depression and experiencing an acute exacerbation of depressive symptoms, will be enrolled. The study will consist of four phases: a screening/tolerability phase of up to 7 days; an open-label, flexible-dose lead-in phase of 8 weeks; an open-label, fixed-dose stabilization phase of 6 weeks; and a single-blind relapse prevention phase of 12 months. During the open-label phase, all patients will be treated with venlafaxine. Remitters with Hamilton Rating Scale for Depression (HAM-D17) score ≤7 will be eligible to enter the single-blind phase and will be randomly assigned to one of three groups: group 1 on active rTMS and venlafaxine; group 2 on sham rTMS and venlafaxine; and group 3 on venlafaxine alone. Efficacy will be evaluated during the study using relapse assessment (time between subject randomization to treatment and the first occurrence of relapse). Secondary outcome measures will include: symptom changes, measured by the HAM-D17; illness severity changes, measured by the Clinical Global Impression of Severity for Depression (CGI-S-DEP); and changes in subject functioning, assessed with the Personal and Social Performance (PSP)scale. Safety will be assessed throughout the study by monitoring of adverse events, clinical laboratory tests, electrocardiography (ECG), and measurements of vital signs (temperature, pulse, and blood pressure) and weight. Suicidality will be assessed by the Columbia Suicide Severity Rating Scale (C-SSRS).DiscussionThe result of this trial will assess the efficacy of rTMS in the prevention of relapse of symptoms of depression by determining whether rTMS in combination with an antidepressant is more efficacious than the antidepressant alone for maintenance of the clinical response.Trial registrationClinicalTrials.gov,NCT01516931

Quetiapine and repetitive transcranial magnetic stimulation ameliorate depression-like behaviors and up-regulate the proliferation of hippocampal-derived neural stem cells in a rat model of depression: The involvement of the BDNF/ERK signal pathway.

Quetiapine (QUE) and repetitive transcranial magnetic stimulation (rTMS) have been considered to be possible monotherapies for depression or adjunctive therapies for the treatment of the resistant depression, but the underlying mechanisms remain unclear. The present study aimed to assess the effects of combined QUE and rTMS treatment on depressive-like behaviors, hippocampal proliferation, and the in vivo and in vitro expressions of phosphorylated extracellular signal-regulated protein kinase (pERK1/2) and brain-derived neurotrophic factor (BDNF) in male Sprague-Dawley rats. The administration of QUE and rTMS was determined not only to reverse the depressive-like behaviors of rats exposed to chronic unpredictable stress (CUS) but also to restore the protein expressions of pERK1/2 and BDNF and cell proliferation in the hippocampus. Additionally, QUE and rTMS promoted the proliferation and increased the expression of pERK1/2 and BDNF in hippocampal-derived neural stem cells (NSCs), and these effects were abolished by U0126. Taken together, these results suggest that the antidepressive-like effects of QUE and rTMS might be related to the activation of the BDNF/ERK signaling pathway and the up-regulation of cell proliferation in the hippocampus.