Evaluating the protective effect of etazolate on memory impairment, anxiety- and depression-like behaviors induced by post traumatic stress disorder

Cannabidiol ameliorates PTSD-like symptoms by inhibiting neuroinflammation through its action on CB2 receptors in the brain of male mice

Post-traumatic stress disorder (PTSD) is a debilitating mental health disease related to traumatic experience, and its treatment outcomes are unsatisfactory. Accumulating research has indicated that cannabidiol (CBD) exhibits anti-PTSD effects, however, the underlying mechanism of CBD remains inadequately investigated. Although many studies pertaining to PTSD have primarily focused on aberrations in neuronal functioning, the present study aimed to elucidate the involvement and functionality of microglia/macrophages in PTSD while also investigated the modulatory effects of CBD on neuroinflammation associated with this condition. We constructed a modified single-prolonged stress (SPS) mice PTSD model and verified the PTSD-related behaviors by various behavioral tests (contextual freezing test, elevated plus maze test, tail suspension test and novel object recognition test). We observed a significant upregulation of Iba-1 and alteration of microglial/macrophage morphology within the prefrontal cortex and hippocampus, but not the amygdala, two weeks after the PTSD-related stress, suggesting a persistent neuroinflammatory phenotype in the PTSD-modeled group. CBD (10 mg/kg, i.p.) inhibited all PTSD-related behaviors and reversed the alterations in both microglial/macrophage quantity and morphology when administered prior to behavioral assessments. We further found increased pro-inflammatory factors, decreased PSD95 expression, and impaired synaptic density in the hippocampus of the modeled group, all of which were also restored by CBD treatment. CBD dramatically increased the level of anandamide, one of the endocannabinoids, and cannabinoid type 2 receptors (CB2Rs) transcripts in the hippocampus compared with PTSD-modeled group. Importantly, we discovered the expression of CB2Rs mRNA in Arg-1-positive cells in vivo and found that the behavioral effects of CBD were diminished by CB2Rs antagonist AM630 (1 mg/kg, i.p.) and both the behavioral and molecular effects of CBD were abolished in CB2Rs knockout mice. These findings suggest that CBD would alleviate PTSD-like behaviors in mice by suppressing PTSD-related neuroinflammation and upregulation and activation of CB2Rs may serve as one of the underlying mechanisms for this therapeutic effect. The present study offers innovative experimental evidence supporting the utilization of CBD in PTSD treatment from the perspective of its regulation of neuroinflammation, and paves the way for leveraging the endocannabinoid system to regulate neuroinflammation as a potential therapeutic approach for psychiatric disorders.

Cilostazol pretreatment prevents PTSD-related anxiety behavior through reduction of hippocampal neuroinflammation

Current pharmacological treatments against post-traumatic stress disorder (PTSD) lack adequate efficacy. As a result, intense research has focused on identifying other molecular pathways mediating the pathogenesis of this condition. One such pathway is neuroinflammation, which has demonstrated a role in PTSD pathogenesis by causing synaptic dysfunction, neuronal death, and functional impairment in the hippocampus. Phosphodiesterase (PDE) inhibitors (PDEIs) have emerged as promising therapeutic agents against neuroinflammation in other neurological conditions. Furthermore, PDEIs have shown some promise in animal models of PTSD. However, the current model of PTSD pathogenesis, which is based on dysregulated fear learning, implies that PDE inhibition in neurons should enhance the acquisition of fear memory from the traumatic event. As a result, we hypothesized that PDEIs may improve PTSD symptoms through inhibiting neuroinflammation rather than long-term potentiation-related mechanisms. To this end, we tested the therapeutic efficacy of cilostazol, a selective inhibitor of PDE3, on PTSD-related anxiety symptoms in the underwater trauma model of PTSD. PDE3 is expressed much more richly in microglia and astrocytes compared to neurons in the murine brain. Furthermore, we used hippocampal indolamine 2,3-dioxygenase 1 (IDO) expression and interleukin 1 beta (IL-1β) concentration as indicators of neuroinflammation. We observed that cilostazol pretreatment prevented the development of anxiety symptoms and the increase in hippocampal IDO and IL-1β following PTSD induction. As a result, PDE3 inhibition ameliorated the neuroinflammatory processes involved in the development of PTSD symptoms. Therefore, cilostazol and other PDEIs may be promising candidates for further investigation as pharmacological therapies against PTSD.

Synergistic effects of combined therapy with cerebrolysin and enriched environment on anxiety-like behavior and spatial cognitive deficits in posttraumatic stress disorder-like mouse model

Posttraumatic stress disorder (PTSD) is a serious neuropsychiatric disorder that occurs after exposure to stressful, fearful, or troubling events. Cerebrolysin (CBL), consists of low molecular weights neurotrophic factors and amino acids obtained from purified porcine brain proteins. This study aimed to evaluate the possible therapeutic effects of enriched environment (EE) and CBL alone or combined for reducing anxiety and cognitive deficits in PTSD-like mouse models. For this purpose, inescapable electric foot shocks were delivered to Balb/c mice for two consecutive days. Then mice were treated with CBL (2.5 mL/kg) and/or were kept in EE (2 h per day) or received their combination for 14 consecutive days. The hole-board test and Lashley III paradigm were used to assess anxiety and spatial learning and memory, respectively. Changes in the serum corticosterone level and expression of synaptic elements, including; growth-associated protein 43, post-synaptic density 95, and synaptophysin were assessed in the hippocampus. This model caused anxiety and spatial memory impairment associated with increased serum corticosterone levels and decreased synaptic elements. Nevertheless, CBL and/or combination treatment could reverse behavioral and molecular alterations. Our findings indicated that CBL, separately or in combination with EE, is effective in reducing anxiety and spatial memory impairment in PTSD-like mice.

Phosphodiesterase inhibitors in psychiatric disorders

RATIONALE

Challenges in drug development for psychiatric disorders have left much room for the introduction of novel treatments with better therapeutic efficacies and indices. As a result, intense research has focused on identifying new targets for developing such pharmacotherapies. One of these targets may be the phosphodiesterase (PDE) class of enzymes, which play important roles in intracellular signaling. Due to their critical roles in cellular pathways, these enzymes affect diverse neurobiological functions from learning and memory formation to neuroinflammation.

OBJECTIVES

In this paper, we reviewed studies on the use of PDE inhibitors (PDEIs) in preclinical models and clinical trials of psychiatric disorders including depression, anxiety, schizophrenia, post-traumatic stress disorder (PTSD), bipolar disorder (BP), sexual dysfunction, and feeding disorders.

RESULTS

PDEIs are able to improve symptoms of psychiatric disorders in preclinical models through activating the cAMP-PKA-CREB and cGMP-PKG pathways, attenuating neuroinflammation and oxidative stress, and stimulating neural plasticity. The most promising therapeutic candidates to emerge from these preclinical studies are PDE2 and PDE4 inhibitors for depression and anxiety and PDE1 and PDE10 inhibitors for schizophrenia. Furthermore, PDE3 and 4 inhibitors have shown promising results in clinical trials in patients with depression and schizophrenia.

CONCLUSIONS

Larger and better designed clinical studies of PDEIs in schizophrenia, depression, and anxiety are warranted to facilitate their translation into the clinic. Regarding the other conditions discussed in this review (most notably PTSD and BP), better characterization of the effects of PDEIs in preclinical models is required before clinical studies.

Long-term treatment with roflumilast improves learning of fear extinction memory and anxiety-like response in a type-1 diabetes mellitus animal model

Diabetic encephalopathy is related to serious damage to the Central Nervous System leading to several disturbances in memory processing and emotions. It is known that the cyclic adenosine 3',5'-monophosphate (cAMP) responsive element-binding protein (CREB) pathway participates in neuronal plasticity and prevention of neuroinflammation, as well as the mediation of learning/memory processes and emotions in brain areas such as the hippocampus (HIP) and prefrontal cortex (PFC). We aimed to investigate the effect of acute (one injection) and long-term treatment (21 days) with roflumilast (ROF; i.p.; 0, 0.01, 0.03, 0.1 mg/kg), a drug able to inhibit the enzyme phosphodiesterase-4 (PDE-4) responsible for cAMP hydrolysis, on parameters related to the acquisition of fear extinction memory and anxiety-like responses in animals with type-1 diabetes mellitus (T1DM) induced through one injection of streptozotocin (60 mg/kg; ip; STZ animals). When we performed acute treatment, no difference was observed between all the groups when resubmitted to the same context paired with an aversive stimulus (footshock) or to a neutral context. In contrast, long-term treatment was able to improve learning of extinction fear memory and discriminating between a conditioned and neutral context. Moreover, this treatment decreased the pronounced anxiety-like response of STZ animals. In addition, there was an increase in the product of the CREB signaling pathway, the pro brain-derived neurotrophic factor, in the HIP and PFC of these animals. The treatment did not impair glycemic control, whereas it decreased the animal's blood glucose levels. To conclude, these findings suggest that ROF treatment repositioning has potential for future translational investigations involving diabetic patients considering its beneficial effects on emotional processes related to fear memory and anxiety, in addition to improvement of glycemic control.

Antioxidants Activity Assessment and Utilization of Banana Peels to Attenuate the Diabetes Mellitus

Diabetes is the primary metabolic disorder listed among the top 10 death-causing diseases. The complete cure of diabetes is impossible, but the prevention and maintenance of glucose levels can reduce the diabetes severity. Objectives: To utilize the banana peel extracts to evaluate their antioxidant attributes and capability to attenuate diabetes. Methods: The antioxidant properties were assessed by measuring the DPPH, total phenolic contents (TPC), and total flavonoid contents (TFC) in ethanol, methanol, and acetone solutions. Moreover, the renal functional tests (Serum creatinine, serum urea, and BUN) and liver function tests (ALT, ASP, Serum Albumin, and total proteins) were also conducted during the 21 days experimental study in diabetes-induced (via Streptozotocin: 350 mg/kg) male Albino Wister rats. Results: The results indicated that the DPPH, TPC, and TFC contents were higher in methanol solution, i.e., 74.20±0.98%, 54.78±0.69mg GAE/g, and 39.48±0.37mg GAE/g respectively. Moreover, the results indicated that the unripe, ripe, and overripe significantly reduced liver and renal function parameters in diabetic rats. Conclusions: Banana peels have prominent potential to prevent diabetes-linked variables due to their higher antioxidant activity.

L-Carnitine prevents memory impairment induced by post-traumatic stress disorder

BACKGROUND

Post-traumatic stress disorder (PTSD) is a genuine obstructing mental disorder. As indicated by the name, it is related to the patients' stress augmented by life-threatening conditions or accidents. The PTSD has linked to oxidative stress that can result in neurodegeneration. L-carnitine (L-CAR) is known for its antioxidant properties, which can protect against neuronal damage.

OBJECTIVE

In the current study, we investigated the beneficial effects of L-CAR on the memory impairment induced by PTSD using a rat model.

METHODS

A model of single-prolonged stress (a cycle of restraining, forced swimming, rest, and finally diethyl ether exposure for 2 h, 20 min, 15 min, and 1-2 min, respectively) was used to induce PTSD-like behavior. Intraperitoneal L-CAR treatment (300 mg/kg/day) was introduced for four weeks. Both memory and special learning were evaluated utilizing the radial arm water maze (RAWM). Moreover, the levels of glutathione peroxidase (GPx), glutathione reduced (GSH), and glutathione oxidized (GSSG) were assessed as biomarkers oxidative stress in the hippocampus.

RESULTS

The results demonstrated that both the short and long-term memories were impaired by PTSD/SPS model (P <  0.05), while L-CAR treatment prevented this memory impairment in PTSD rats. Besides, L-CAR prevented the reduction in GPx activity and increase in GSSG, which were altered in the hippocampus of the PTSD/SPS rats (P <  0.05). Levels of GSH were not changed in PTSD and/or L-CAR rats.

CONCLUSIONS

L-CAR administration prevented short- and long-term memories' impairments induced in the PTSD/SPS rat model. This is probably related to its antioxidant effects in the hippocampus.

Phosphodiesterase-2 inhibitor reverses post-traumatic stress induced fear memory deficits and behavioral changes via cAMP/cGMP pathway

Phosphodiesterase 2 is one of the phosphodiesterase (PDEs) family members that regulate cyclic nucleotide (namely cAMP and cGMP) concentrations. The present study determined whether PDE2 inhibition could rescue post-traumatic stress disorder (PTSD)-like symptoms. Mice were subjected to single prolonged stress (SPS) and treated with selective PDE2 inhibitor Bay 60-7550 (0.3, 1, or 3 mg/kg, i.p.). The behavioral tests such as forced swimming, sucrose preference test, open field, elevated plus maze, and contextual fear paradigm were conducted to determine the effects of Bay 60-7550 on SPS-induced depression- and anxiety-like behavior and fear memory deficits. The results suggested that Bay 60-7550 reversed SPS-induced depression- and anxiety-like behavior and fear memory deficits. Moreover, Bay 60-7550 prevented SPS-induced changes in the adrenal gland index, synaptic proteins synaptophysin and PSD95 expression, PKA, PKG, pCREB, and BDNF levels in the hippocampus and amygdala. These effects were completely prevented by PKG inhibitor KT5823. While PKA inhibitor H89 also prevented Bay 60-7550-induced pCREB and BDNF expression, but only partially prevented the effects on PSD95 expression in the hippocampus. These findings suggest that Bay 60-7550 protects mice against PTSD-like stress induced traumatic injury by activation of cGMP- or cAMP-related neuroprotective molecules, such as synaptic proteins, pCREB and BDNF.

High intensity interval training protects from Post Traumatic Stress Disorder induced cognitive impairment

This study aimed to show the possible protective effects of high intensity interval training (HIIT) in PTSD-induced rats and probable underlying mechanisms. Female rats (n = 44) were separated as; Sedentary (SED), moderate intensity continuous training (MICT), HIIT groups. Then the groups were divided into subgroups according to PTSD induction (n = 6-8/group). Exercise groups performed HIIT or MICT for 6 weeks. On the fifth week, PTSD was induced by single prolonged stress protocol. Cognitive functions were evaluated by object recognition, anxiety levels by hole-board and elevated plus maze, and fear conditioning by passive avoidance tests. Following decapitation, malondialdehyde (MDA), glutathione (GSH), luminol and lucigenin chemiluminescence levels, and myeloperoxidase (MPO), superoxide dismutase (SOD) and catalase (CAT) activities were measured, and histopathological damage was evaluated. The data was analyzed by one-way ANOVA. Cognitive decline and aggravated anxiety levels in SED + PTSD group were improved in both PTSD-induced exercise groups (p < 0.05-0.001). The increased chemiluminescence levels, MPO activity and histological damage were depressed in both PTSD-induced exercise groups (p < 0.05-0.001). The risen MDA levels in SED + PTSD group were suppressed only in HIIT + PTSD group (p < 0.01-0.001). The decreased GSH levels were increased by MICT (p < 0.05-0.001), and CAT and SOD activities were improved via HIIT (p < 0.05). Compared to SED group, latency was decreased in SED + PTSD (p < 0.05-0.01) group. Neuronal damage scores were alleviated in both PTSD-induced exercise groups (p < 0.001). PTSD-induced memory decline was protected by both of the exercise models however more effectively by HIIT via decreasing oxidative stress, anxiety levels and by improving antioxidant capacity as a protective system for neuronal damage.

Vitamin C attenuates memory loss induced by post-traumatic stress like behavior in a rat model

Oxidative stress is associated with neuronal damage in many brain regions including the hippocampus; an area in the brain responsible of memory processing. Oxidative stress is also linked with many psychiatric conditions including post-traumatic stress disorder (PTSD). PTSD is triggered by traumatic experience and many PTSD patients show signs of memory impairment. Vitamin C is a water-soluble vitamin with antioxidant properties. Herein, we hypothesized that memory impairment observed during PTSD could be a result of oxidative stress in hippocampal tissues and that prophylactic vitamin C administration may reduce oxidative stress in the hippocampus and prevent memory impairment. The above hypothesis was tested in a rat model where PTSD-like behavior was induced through single prolonged stress (SPS). Short and long-term memory was tested using a radial arm water maze (RAWM). We found that SPS induced a significant increase in the oxidized glutathione levels of the hippocampus. This reduction was accompanied with a significant decrease in glutathione peroxidase and catalase enzyme activity, and a significant increase in lipid peroxidation. Intriguingly, vitamin C administration successfully attenuated memory impairment and all of the changes observed in oxidative stress markers. Our findings demonstrate that vitamin C could prevent oxidative stress and memory impairment induced by SPS model of PTSD-like behavior in rat.

Vitamin E prevents the cognitive impairments in post-traumatic stress disorder rat model: behavioral and molecular study

RATIONALE

Post-traumatic stress disorder (PTSD) is a psychiatric disorder developed after an exposure to severe traumatic events. Patients with PTSD suffer from different symptoms including memory impairment. In addition, PTSD is associated with oxidative stress. Vitamin E, a fat-soluble vitamin, possesses cognition protective effects via its antioxidative properties.

OBJECTIVES

To investigate the impact of vitamin E on memory impairment induced by PTSD in animals.

METHODS

A rat model of PTSD-like behavior and the radial arm water maze (RAWM) for testing of learning and memory paradigm were used. Rats were divided into 4 groups: control, vitamin E, PTSD, and vitamin E + PTSD.

RESULTS

In the learning phase, results showed no significant differences among experimental groups, indicating that PTSD-like behavior did not impair learning ability in rats. However, memory tests in the RAWM showed that PTSD-like animals had impairment in both short-term and long-term memories. Vitamin E, on the other hand, prevented this impairment of memory. With respect to oxidative stress, significant decreases were detected in reduced glutathione/oxidized glutathione (GSH/GSSG) ratio, glutathione peroxidase (GPx) and catalase enzyme activities, global histone 3 acetylation, and brain derived neurotrophic factor (BDNF) levels in the PTSD-like animals group compared with other groups (P < 0.05). Vitamin E protected the reduction of these oxidative stress biomarkers, global histone 3 acetylation, and BDNF levels.

CONCLUSIONS

Vitamin E prevented memory impairment associated with PTSD-like behavior in animals, probably via its antioxidative properties, and preservation of epigenetic changes induced in PTSD-like animals.

Edaravone prevents memory impairment in an animal model of post-traumatic distress

Post-traumatic stress disorder (PTSD) is a mental health problem that develops in a proportion of individuals after experiencing a potential life-threatening traumatic stress event. Edaravone is a free radical scavenger, with a neuroprotective effect against cognitive impairment in several animal models. In the present study, the protective effect of edaravone on PTSD-induced memory impairment was investigated. Single prolonged stress was used as an animal model of PTSD, comprising 2 h of restrain, 20-min forced swimming, 15-min rest, and 1-2-min diethyl ether exposure. Concurrently, edaravone was given at a dose of 6 mg/kg/day, intraperitoneally, for 21 days. The radial arm water maze was used to assess learning and memory. Antioxidant biomarkers were measured in hippocampus tissues. Chronic administration of edaravone prevented impairment of short-term and long-term memory. Edaravone also prevented the stress-induced decrease in the ratio of reduced glutathione/oxidized glutathione and the activities of glutathione peroxidase and catalase enzymes in the hippocampus, as well as increases in the levels of oxidized glutathione and thiobarbituric acid reactive substances. In conclusion, edaravone ameliorated oxidative stress and cognitive impairment associated with a PTSD model, probably by supporting antioxidant mechanism in the hippocampus.

Effects of Exercise on Memory Interference in Neuropsychiatric Disorders

There are several mechanisms that cause memory impairment, including motivated forgetting, active forgetting, natural decay, and memory interference. Interference occurs when one is attempting to recall something specific, but there is conflicting information making it more difficult to recall the target stimuli. In laboratory settings, it is common to measure memory interference with paired associate tasks-usually utilizing the AB-CD, AB-AC, AB-ABr, or AB-DE AC-FG method. Memory impairments are frequent among those with neuropsychiatric disorders such as depression, schizophrenia, and multiple sclerosis. The memory effects of each condition differ, but are all related to alterations in brain physiology and general memory deterioration. Exercise, or physical activity, has been demonstrated to attenuate memory interference in some cases, but the mechanisms are still being determined. Further research is needed on memory interference, in regard to exercise and neuropsychiatric disorders.

Heparin Modulates the Main Properties of the Central Nervous System in Experimental Post-Traumatic Stress Disorder: A New Concept of the Mechanisms of Pathogenesis and Treatment

Elevated plus-maze test was used to reveal the role of excitation and inhibition mechanisms in the CNS in the organization of the behavior of male Wistar rats under normal conditions and during modeling experimental post-traumatic stress disorder (with or without administration of low doses of high-molecular-weight heparin). The data about insufficiency in the system of excitation mechanisms and pronounced excess in the system of inhibition mechanisms in post-traumatic stress disorder are prioritized. Heparin seems to be a promising and effective preparation to cope with extreme psychotraumatic abnormalities in CNS.

Molecular targets for the interactive effect of etazolate during post-traumatic stress disorder: Role of oxidative stress, BDNF and histones

Post-traumatic stress disorder (PTSD) develops in individuals after exposure to severe, life-threatening traumatic event. Etazolate is a selective phosphodiesterase IV inhibitor that is highly specific for cAMP, which has anxiolytic and antidepressant effects. We have previously shown that PTSD induced-memory impairment, anxiety and depression were prevented via the administration of etazolate. In the current study, the effect of etazolate on oxidative stress parameters, BDNF, and histone acetylation in the hippocampus were evaluated in a rat model of PTSD. The PTSD was induced by single prolonged stress (SPS) model. Etazolate was administered orally at a dose of 1 mg/kg/day for one month. At the end of the treatment period, the hippocampus was dissected and oxidative stress biomarkers (GSH, GSSG, GPx and TBARS), BDNF protein level, and histone acetylation were assessed. Results revealed that PTSD potentiated oxidative stress in the hippocampus and induced significant reductions in BDNF level and histones acetylation (P < 0.05). Etazolate treatment, on the other hand, led to prevention of changes in these oxidative stress biomarkers (GSH, GSSG, GPx and TBARS), BDNF levels, and histones acetylation. In conclusion, oxidative stress and modulation of BDNF and histones acetylation induced by PTSD can be prevented by treatment with etazolate.

Omega-3 Fatty Acids Prevent Post-Traumatic Stress Disorder-Induced Memory Impairment

Post-traumatic stress disorder (PTSD) is a psychiatric disorder that can happen after exposure to a traumatic event. Post-traumatic stress disorder is common among mental health disorders that include mood and anxiety disorders. Omega-3 fatty acids (OMGs) are essential for the maintenance of brain function and prevention of cognition dysfunctions. However, the possible effect of OMG on memory impairment induced by PTSD has not been studied. In here, such an effect was explored using a rat model of PTSD. The PTSD-like behavior was induced in animals using a single-prolonged stress (SPS) rat model of PTSD (2 h restraint, 20 min forced swimming, 15 min rest, 1–2 min diethyl ether exposure). The OMG was administered orally at a dose of 100 mg omega-3 polyunsaturated fatty acid (PUFA)/100 g body weight/day. Spatial learning and memory were assessed using the radial arm water maze (RAWM) method. Changes in oxidative stress biomarkers, thiobarbituric acid reactive substances (TBARS), and brain derived neuroptrophic factor (BDNF) in the hippocampus following treatments were measured. The results revealed that SPS impaired both short- and long-term memory (p < 0.05). Use of OMG prevented memory impairment induced by SPS. Furthermore, OMG normalized SPS induced changes in the hippocampus that reduced glutathione (GSH), oxidized glutathione (GSSG), GSH/GSSG ratios, the activity of catalase, glutathione peroxidase (GPx), and TBARSs levels. In conclusion, the SPS model of PTSD-like behavior generated memory impairment, whereas OMG prevented this impairment, possibly through normalizing antioxidant mechanisms in the hippocampus.

Prevention of memory impairment induced by post-traumatic stress disorder by cerebrolysin

Post-traumatic stress disorder (PTSD) may occur after exposure to stressful, fearful or troubling events. Until now, there is no curable medication for this disorder. Cerebrolysin is a neuropeptide, which has an important role in the treatment of vascular dementia. In this study, the probable protective effect of cerebrolysin on PTSD-induced memory impairment was investigated. To induce PTSD, the single prolonged stress (SPS) model was used. Rats were allocated into four groups: control (vehicle-treated), CBL (administrated cerebrolysin 2.5 ml/kg by intraperitoneal route for 4 weeks), SPS (as a model of PTSD and administered vehicle), and CBL-SPS (exposed to SPS and administered cerebrolysin for 4 weeks). Learning and memory were assessed using the radial arm water maze (RAWM). Results showed that SPS impaired both short- and long- term memories; and chronic cerebrolysin administration prevented such effect. Cerebrolysin also prevented decreases in hippocampal GSH levels and GSH/GSSG ratios, and increased GSSG and TBARs, levels induced by PTSD. In conclusion, a protective effect of cerebrolysin administration against SPS model of PTSD induced short- and long- term memory impairment was characterized. This protection could be accomplished, at least partly, by prevention of PTSD induced increase in oxidative stress in the hippocampus via the use of cerebrolysin.

Beneficial effect of etazolate on depression-like behavior and, learning, and memory impairment in a model of Parkinson's disease

The aim of this study was to evaluate etazolate against depression-like behavior and, learning and memory impairment induced by 6- hydroxydopamine (6-OHDA) rat model of Parkinson's disease (PD). This aim was achieved through comparing 6-OHDA lesioned rats in the presence and absence of etazolate. The 6-OHDA was used to induce lesion as a model of PD. Etazolate was administered at a dose of 1 mg/kg/day for 14 days, starting 7 days after lesion induction. Apomorphine-induced rotation test was used to evaluate 6-OHDA-induced motor deficits, tail suspension test was used to assess depression-like symptoms, and the radial arms water maze (RAWM) was used to evaluate special learning and memory functions. Antioxidant biomarkers and BDNF protein levels were assessed in the hippocampus. Results revealed that etazolate administration significantly improved 6-OHDA-induced PD related symptoms including motor deficits, depression-like behavior and impairment of both short- and long- term memory. Moreover, etazolate significantly prevented 6-OHDA-induced reduction in oxidative stress biomarkers (GSH/GSSG ratio, GPx) and BDNF levels. In conclusion, motor dysfunction, depressive- like behavior, and learning and memory deficits in the 6-OHDA rat model of PD can be significantly prevented by etazolate. This prevention could be attributed to etazolate's ability to prevent reduction in antioxidative stress biomarkers and BDNF levels.