chronic unpredictable stress

Chronic stress is a major cause of anxiety disorders that can be reliably modeled pre-clinically, providing insight into alternative therapeutic targets for this mental health illness. Neuropeptides have been targeted in the past to no avail possibly due to our lack of understanding of their role in pathological models. In this study we use a rat model of chronic stress-induced anxiety-like behaviours and hypothesized that neuropeptidergic modulation of synaptic transmission would be altered in the Bed Nucleus of the Stria Terminalis (BNST), a brain region suspected to contribute to anxiety disorders...

Unlike majority of current antidepressants, HBK-15-a 5-HT1A and 5-HT7 receptor antagonist - showed memory-enhancing properties. In this study, we aimed to further characterize pharmacological profile of HBK-15 and investigate its antidepressant- and anxiolytic-like activity in the mouse model of unpredictable chronic mild stress. We used sucrose consumption test, forced swim test and elevated plus maze and evaluated the influence on brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF) levels in the hippocampus and prefrontal cortex, as well as body weight, relative adrenal glands weight and plasma corticosterone level in the stressed mice...

ETHNOPHARMACOLOGICAL RELEVANCE: Maerua angolensis DC (Capparaceae) has been employed in the management of several central nervous system (CNS) disorders including anxiety. This study evaluated the anxiolytic effects of the petroleum ether/ethyl acetate fraction stem bark extract and its possible mechanism(s) using zebrafish anxiety models. METHODS: Adult zebrafish, tested in the novel tank and light dark tests, have shown by previous authors to be sensitive to the anxiolytic effects of known anxiolytic drugs...

BACKGROUND Major depressive disorder (MDD) is a recurrent mental illness worldwide. The glutamatergic neurotransmission system is now a target for antidepressant therapy because it takes part in synaptic plasticity and cognition in physical condition and has a potential excitatory neurotoxicity in pathological conditions. Glial glutamate transporter EAAT2 performs 90% of Glu neurotransmission. Therefore, the aim of the study was to evaluate the effect of acupuncture on depressive behaviors and EAAT2 in CUMS...

BACKGROUND: Chronic stress induces an impaired GABAA (γ-aminobutyric acid type A) receptor-mediated inhibition in the hypothalamic paraventricular nucleus (PVN). It is not clear whether GABAB receptor function is altered in chronic stress. We hypothesize that chronic stress alters GABAB receptor function in PVN corticotrophin-releasing hormone (CRH) neurons to control hypothalamus-pituitary-adrenal (HPA) axis activity. EXPERIMENTAL APPROACH: Whole cell patch-clamp recording was performed on PVN-CRH neurons expressing eGFP driven by CRH promoter in brain slices from unstressed rats and rats that had been subjected to chronic unpredictable mild stress (CUMS)...

BACKGROUND: Hippocampal volume loss is a hallmark of clinical depression. Chronic stress produces volume loss in the hippocampus in humans and atrophy of CA3 pyramidal cells and suppression of adult neurogenesis in rodents. METHODS: To investigate the relationship between decreased adult neurogenesis and stress-induced changes in hippocampal structure and volume, we compared the effects of chronic unpredictable restraint stress and inhibition of neurogenesis in a rat pharmacogenetic model...

BACKGROUND: Xiao Yao San (XYS) is an herbal prescription which is used in the treatment of depression for thousands of years from Song dynasty in China (960-1127 A.D.), and is the bestselling and most popular herb formula for treating major depression. This study aimed to assess the chronic antidepressant effects of XYS and fluoxetine in depressed mice induced by chronic unpredictable mild stress (CUMS) and its association with  alterations in glutamate/glutamine cycle and glutamate transporters...

Chronic stress enhances risk for psychiatric disorders, and in animal models is known to evoke depression-like behavior accompanied by perturbed neurohormonal, metabolic, neuroarchitectural and transcriptional changes. Serotonergic neurotransmission, including serotonin2A (5-HT2A) receptors, have been implicated in mediating specific aspects of stress-induced responses. Here we investigated the influence of chronic unpredictable stress (CUS) on depression-like behavior, serum metabolic measures, and gene expression in stress-associated neurocircuitry of the prefrontal cortex (PFC) and hippocampus in 5-HT2A receptor knockout (5-[Formula: see text]) and wild-type mice of both sexes...

Our previous studies have demonstrated that prenatal caffeine exposure (PCE) induced an intrauterine programming of hypothalamic-pituitary-adrenal axis (HPAA)-associated neuroendocrine metabolism in 3-month-old offspring rats. In this study, we aimed to confirm this programming disorder and high susceptibility to metabolic syndrome (MS) in 10-month-old female PCE offspring with postnatal catch-up growth. We found that PCE female offspring rats showed decreased bodyweight but a higher rate of weight gain after birth...

Depression is a world-wide disease with no effective therapeutic methods. Increasing evidence indicates that astrocytic pathology contributes to the formation of depression. In this study, we investigated the effects of harmine, a natural β-carboline alkaloid and potent hallucinogen, known to modulate astrocytic glutamate transporters, on chronic unpredictable stress (CUS)-induced depressive-like behaviors and astrocytic dysfunctions. Results showed that harmine treatment (10, 20mg/kg) protected the mice against the CUS-induced increases in the immobile time in the tail suspension test (TST) and forced swimming test (FST), and also reversed the reduction in sucrose intake in the sucrose preference experiment...

Major depression has been interpreted as an inflammatory disease characterized by cell-mediated immune activation, which is generally triggered by various stresses. Microglia has been thought to be the cellular link between inflammation and depression-like behavioural alterations. The expression of cathepsin C (Cat C), a lysosomal proteinase, is predominantly induced in microglia in neuroinflammation. However, little is known about the role of Cat C in pathophysiology of depression. In the present study, Cat C transgenic mice and wild type mice were subjected to an intraperitoneal injection of LPS (0...

BACKGROUND: Hypothalamic-pituitary-adrenal (HPA) axis hyperactivity is a well-established pathological feature of major depression, accompanied by the persistent increase of glucocorticoid level and the dysfunction of hypothalamic-pituitary-gonadal (HPG) axis. Ginsenoside Rg1 (Rg1) is one of the most active ingredients of Panax ginseng, which has various biological activity. OBJECTIVE: This study aimed to investigate the antidepressive effects of Rg1 and elucidate its impact on neuroendocrine system...

Resolvin D1 (RvD1) and D2 (RvD2) are lipid mediators that are derived from docosahexaenoic acid. We recently demonstrated that intracerebroventricular (i.c.v.) infusions of RvD1 or RvD2 attenuate lipopolysaccharide-induced depression-like behaviors via mammalian target of rapamycin complex 1 signaling. However, the antidepressant effects of RvD1 and RvD2 have not been fully investigated. Here, we examined the antidepressant effects of RvD1 and RvD2 using the tail suspension test (TST) and forced swim test (FST) in murine chronic unpredictable stress (CUS) model...

The C57BL6/J mouse is the most commonly used strain in genetic investigations and behavioural tests. However, only a few studies have used C57BL6/J mice to assess the effects of antidepressant compounds. We carried out a study to compare the behavioural effects of fluoxetine (FLX) in a model of depression in two mice strains: C57BL6/J and BALB/c. We used an 8-week unpredictable chronic mild stress (UCMS) protocol during which FLX was administered (15 mg/kg, oral) from the third week to the end of the protocol...

OBJECTIVE: Fos protein expression in catecholamine-synthesizing neurons of the substantia nigra (SN) pars compacta (SNC, A8), pars reticulata (SNR, A9), and pars lateralis (SNL), the ventral tegmental area (VTA, A10), the locus coeruleus (LC, A6) and subcoeruleus (sLC), the ventrolateral pons (PON-A5), the nucleus of the solitary tract (NTS-A2), the area postrema (AP), and the ventrolateral medulla (VLM-A1) was quantitatively evaluated aft er a single administration of asenapine (ASE) (designated for schizophrenia treatment) in male Wistar rats preconditioned with a chronic unpredictable variable mild stress (CMS) for 21 days...

Depression is a prevalent psychiatric disorder with an increasing impact in global public health. However, a large proportion of patients treated with currently available antidepressant drugs fail to achieve remission. Recently, antipsychotic drugs have received approval for the treatment of antidepressant-resistant forms of major depression. The modulation of adult neuroplasticity, namely hippocampal neurogenesis and neuronal remodeling, has been considered to have a key role in the therapeutic effects of antidepressants...

Post-stroke depression (PSD) is the most common mood disorder following a stroke, and is also the main factor limiting recovery and rehabilitation in stroke patients. The present study was aimed to investigate whether Huperzine A (HupA) has antidepressant-like activity in a rat model of PSD, which was developed by middle cerebral artery occlusion followed by an 18-day chronic unpredictable mild stress in conjunction with isolation rearing. The sucrose preference and forced swim tests were used to assess depression-like behavior...

Schizophrenia is a neurodevelopmental disorder in which impaired decision-making and goal-directed behaviors are core features. One of the genes associated with schizophrenia is the Close Homolog of L1 (CHL1); CHL1-deficient mice are considered a model of schizophrenia-like deficits, including sensorimotor gating, interval timing and spatial memory impairments. Here we investigated temporal discounting in CHL1-deficient (KO) mice and their wild-type littermates. Although no discounting differences were found under baseline conditions, CHL1-KO mice showed increased impulsive choice following chronic unpredictable stress (fewer % larger-later choices, and reduced area under the discounting curve)...

Background: Prostaglandin (PG) D2 is the most abundant prostaglandin in the mammalian brain. The physiological and pharmacological actions of PGD2 in the central nervous system seem to be associated with some of the symptoms exhibited by patients with major depressive disorder (MDD). Previous studies have found that PGD2 synthase was decreased in the cerebrospinal fluid of MDD patients. We speculated that there may be a dysregulation of PGD2 levels in MDD. Methods: Ultra-performance liquid chromatography-tandem mass spectrometry coupled with a stable isotopic labeled internal standard was used to determine PGD2 levels in the plasma of MDD patients and in the brains of depressive mice...

Chronic unpredicted mild stress (CUMS)-induced depression could alter the pharmacokinetics of many drugs in rats, however, the underlying mechanism is not clear. In this work we studied the pharmacokinetics of repaglinide, and explored the role of glucocorticoid and adrenergic signaling pathway in regulating drug metabolizing enzymes (DMEs) in GK rats and BRL 3A cells. The plasma cortisol and epinephrine levels were increased, meanwhile the pharmacokinetics of repaglinide were altered significantly in depression model rats...