Natural polyphenols as therapeutic candidates for mitigating neuropsychiatric symptoms in post-traumatic stress disorder: Evidence from preclinical studies.

Post-traumatic stress disorder (PTSD) is a challenging mental health condition that affects millions of people worldwide after they experience traumatic events. The current medications often do not fully address the wide range of PTSD symptoms or the underlying brain mechanisms, prompting the need to explore new treatments. Polyphenols, which are natural compounds found in many plant-based foods, have gained interest due to their brain-protective, anti-inflammatory, and antioxidant benefits.

Stress and glucocorticoids impair inhibitory avoidance memory retrieval and extinction in male mice: the ameliorative effect of Ginkgo biloba extract.

Memory retrieval involves recalling previously consolidated information, while memory extinction refers to the gradual weakening of such memories after recall. Stress and glucocorticoids influence the retrieval and extinction of memory. This study employed a passive avoidance task to examine the impact of acute mild stress and equivalent doses of exogenous corticosterone on fear memory retrieval and extinction in male mice.

Neuroprotective effects of Daphnetin on hippocampal neurons and blood-brain barrier integrity in a mouse model of cerebral ischemia.

The purpose of this research was to assess the impact of different doses of Daphnetin (DAP, a natural compound derived from coumarin) on hippocampus neuronal injury, neurobehavioral function, blood-brain barrier (BBB) integrity, expression of claudin-5, brain-derived neurotrophic factor (BDNF), superoxide dismutase (SOD), and inflammatory markers in a mouse model of cerebral ischemia. Cerebral ischemia was induced in mice through 30 minutes of bilateral common carotid occlusion (BCCAO), followed by 48 hours of reperfusion. The viability of hippocampal neurons was assessed using Cresyl violet staining and BBB function was determined by measuring Evans blue (E.

Systemic corticosterone enhances fear memory extinction in rats: Involvement of the infralimbic medial prefrontal cortex GABA and GABA receptors.

Purpose: The infralimbic (IL) subregion of the medial prefrontal cortex (mPFC) regulates the extinction of conditioned fear memory. Glucocorticoid and gamma-aminobutyric acid (GABA) receptors are expressed in the mPFC and are also critical in fear extinction. This study investigated the possible interactive effects of the glucocorticoids and GABAergic system in the IL on the regulation of fear extinction.

Mild exercise plus levothyroxine ameliorate deficits of spatial navigation, anxiety profile, and hippocampal BDNF in hypothyroid male offspring rats.

Purpose: Levothyroxine (LEV) monotherapy cannot completely improve cognitive and behavioral impairments induced by hypothyroidism, whereas a combination therapy of exercise and LEV may ameliorate these deficits. This study aimed to determine the effects of mild-intensity forced exercise and LEV treatment on the anxiety profile and cognitive functions in male offspring of hypothyroid dams.

Method: Twenty-four female rats (mothers) were randomly divided into sham (healthy) and hypothyroidism groups and then placed with male rats to mate.

Involvement of relaxin-family peptide-3 receptor (RXFP3) in the ventral dentate gyrus of the hippocampus in spatial and fear memory in rats.

The neuropeptide relaxin-3 and its cognate receptor, relaxin family peptide-3 receptors (RXFP3), have been implicated in modulating learning and memory processes, but their specific roles remain unclear. This study utilized behavioral and molecular approaches to investigate the effects of putatively reversible blockade of RXFP3 in the ventral dentate gyrus (vDG) of the hippocampus on spatial and fear memory formation in rats. Male Wistar rats received bilateral vDG cannula implantation and injections of the RXFP3 antagonist, R3(BΔ23-27)R/I5 (400 ng/0.

Saffron and crocin ameliorate prenatal valproic acid-induced autistic-like behaviors and brain oxidative stress in the male offspring rats.

Autism is a neurobehavioral disease that induces cognitive and behavioral alterations, usually accompanied by oxidative stress in the brain. Crocus sativus (saffron) and its active ingredient, crocin, have potent antioxidative effects that may benefit autistic behaviors. This study aimed to determine the effects of saffron extract and crocin against brain oxidative stress and behavioral, motor, and cognitive deficits in an animal model of autism in male offspring rats.

Hypothalamus and Post-Traumatic Stress Disorder: A Review.

Humans have lived in a dynamic environment fraught with potential dangers for thousands of years. While fear and stress were crucial for the survival of our ancestors, today, they are mostly considered harmful factors, threatening both our physical and mental health. Trauma is a highly stressful, often life-threatening event or a series of events, such as sexual assault, war, natural disasters, burns, and car accidents.

Corticosterone injection into the dorsal and ventral hippocampus impairs fear memory reconsolidation in a time-dependent manner in rats.

Reconsolidation is an active process induced following the reactivation of previously consolidated memories. Recent studies suggest brain corticosteroid receptors may participate in the modulation of fear memory reconsolidation. Glucocorticoid receptors (GRs), with 10-fold lower affinity than mineralocorticoid receptors (MRs), are mainly occupied during the peak of the circadian rhythm, and after stress, so they probably have a more critical role than MRs in memory phases during stressful situations.

Glucocorticoid- β-adrenoceptors interactions in the infralimbic cortex in acquisition and consolidation of auditory fear memory extinction in rats.

This study investigated the interactive effect of glucocorticoid and β-adrenoceptors in the infralimbic (IL) cortex on the acquisition and consolidation of fear extinction in rats' auditory fear conditioning (AFC) task. On day 1, rats underwent habituation for 9 min (12 tones, 10 s, 4 kHz, 80 dB, without footshock). On day 2 (conditioning), rats received 3 mild electrical footshocks (US; 2 s, 0.

β-adrenoceptors of the infra-limbic cortex mediate corticosterone-induced enhancement of acquisition and consolidation of fear memory extinction in rats.

The extinction of auditory fear conditioning (AFC) refers to reducing the fear responses induced following repeated presentation of a conditioned stimulus (tone) in the absence of an unconditioned stimulus (electric foot shock). Glucocorticoid receptors (GRs) play an important role in extinction, but the underlying neurobiological mechanisms are unclear. This study aimed to investigate the interaction between glucocorticoids and β-adrenoceptors of the infra-limbic cortex (IL) in regulating the acquisition and consolidation of fear memory extinction in rats.

Role of Amygdala-Infralimbic Cortex Circuitry in Glucocorticoid-induced Facilitation of Auditory Fear Memory Extinction.

Introduction: The basolateral amygdala (BLA) and infralimbic area (IL) of the medial prefrontal cortex (mPFC) are two interconnected brain structures that mediate both fear memory expression and extinction. Besides the well-known role of the BLA in the acquisition and expression of fear memory, projections from IL to BLA inhibit fear expression and have a critical role in fear extinction. However, the details of IL-BLA interaction have remained unclear.

Pre-Ischemic Oxytocin Treatment Alleviated Neuronal Injury via Suppressing NF-κB, MMP-9, and Apoptosis Regulator Proteins in A Mice Model of Stroke.

Objective: This study was designed to determine the effects of pre-ischemic administration of oxytocin (OXT) on neuronal injury and possible molecular mechanisms in a mice model of stroke.

Materials And Methods: In this experimental study, stroke was induced in the mice by middle cerebral artery occlusion (MCAO) for 60 minutes and 24 hours of reperfusion. OXT was given as intranasal daily for 7 consecutive days before ischemic stroke.

Effects of different intensities of treadmill exercise on cued fear extinction failure, hippocampal BDNF decline, and Bax/Bcl-2 ratio alteration in chronic-morphine treated male rats.

Chronic morphine impairs cued fear extinction, which may contribute to the high prevalence of anxiety disorders and the replase of opiate addiction. This work investigated the effects of forced exercise with different intensities on cued fear extinction impairment and alternations of hippocampal BDNF and apoptotic proteins induced by chronic morphine. Rats were injected with bi-daily doses of morphine or saline for ten days and then received a cued or contextual fear conditioning training, which was followed by fear extinction training for four consecutive days.

Chronic light deprivation induces different effects on spatial and fear memory and hippocampal BDNF/TRKB expression during light and dark phases of rat diurnal rhythm.

Disruptions in light/dark cycle have been associated with an altered ability to form and retrieve memory in human and animals. Animal studies have shown that chronic light deprivation disrupts the light/dark cycle and alters the neural connections that mediate hippocampal memory formation. In order to better understand how light deprivation affects the formation and retrieval of memory in adult rats, we examined the effect of total darkness on spatial and auditory fear learning and memory formation and BDNF/TRKB protein levels during the light and dark phases of the rat circadian cycle.

Oxytocin in dorsal hippocampus facilitates auditory fear memory extinction in rats.

Fear extinction is impaired in some psychiatric disorders. Any treatment that facilitates the extinction of fear is a way to advance the treatment of related psychiatric disorders. Recent studies have highlighted the role of oxytocin (OT) in fear extinction, but the endogenous release of OT during fear extinction in the dorsal hippocampal (dHPC) is not clear.

Neuroprotective Effects of Chemerin on a Mouse Stroke Model: Behavioral and Molecular Dimensions.

The present study was conducted to investigate the effects of different doses of recombinant human Chemerin (rhChemerin) on brain damage, spatial memory, blood-brain barrier (BBB) disruption and cellular and molecular mechanisms in a mouse stroke model. The mouse stroke model was developed by blocking the middle cerebral artery for 1 h and performing reperfusion for 23 h. Immediately, one and three hours after the stroke, 200, 400 and 800 ng/mouse of intranasal rhChemerin was administered.

The Effects of Valerian on Sleep Quality, Depression, and State Anxiety in Hemodialysis Patients: A Randomized, Double-blind, Crossover Clinical Trial.

Objectives: Our study sought to determine the effects of valerian on sleep quality, depression, and state anxiety in hemodialysis (HD) patients.

Methods: This randomized, double-blind, placebo-controlled, crossover clinical trial was conducted on 39 patients undergoing HD allocated into a valerian and placebo group. In the first phase of the study, group A (n = 19) received valerian and group B (n = 20) received a placebo one hour before sleep every night for a total of one month.

Prophylactic effect of intranasal oxytocin on brain damage and neurological disorders in global cerebral ischemia in mice.

Objectives: A few experimental studies have shown the therapeutic effects of oxytocin on focal cerebral ischemia. In this study, the prophylactic effect of intranasal oxytocin on brain damage was investigated in a cerebral ischemic model.

Materials And Methods: Intranasal oxytocin (8 IU/per mouse) was prescribed daily for one week.

Role of Hippocampal 5-HT6 Receptors in Glucocorticoid-Induced Enhancement of Memory Consolidation in Rats.

Introduction: of the study: Post-training administration of glucocorticoids enhance memory consolidation of inhibitory avoidance learning. Given the involvement of 5-HT6 receptors in memory processing and the interaction of glucocorticoids with the brain serotonergic system in modulating memory processing, we investigated whether the effect of glucocorticoids on the consolidation of emotionally arousing training depends on hippocampal 5-HT6 receptors.

Methods: Rats were trained in an inhibitory avoidance task and immediately received the systemic injections of corticosterone (CORT) as well as the intra-hippocampal injections of 5-HT receptors agonist or antagonist.

Temporary inactivation of the infralimbic cortex impairs while the blockade of its dopamine D2 receptors enhances auditory fear extinction in rats.

Fear extinction is defined as decline in conditioned fear responses that occurs with repeated and non-reinforced exposure to a feared conditioned stimulus. Experimental evidence suggests that the extinction of fear memory requires the integration of the medial prefrontal cortex (mPFC); nevertheless, the role of its sub-regions in regulating the expression and extinction of auditory fear has been rarely addressed in literature. The present study examined the roles of the infra-limbic (IL) and pre-limbic (PL) regions of the mPFC in the expression and extinction of auditory fear by temporally deactivating these regions using lidocaine (10 μg/0.