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Objective(s): Alzheimer’s disease (AD) is a neurodegenerative disease that results in the gradual breakdown of brain tissue, causing the deterioration of intellectual function and ability. Crocin is a saffron carotenoid compound proven to have excellent neuroprotective and anti-inflammation properties, although it has some limitations such as low stability and bioavailability. Therefore, in the current research, we tried to improve these limitations by using nanotechnology and chitosan as the carrier. Our study examined the therapeutic effects of crocin nano-chitosan-coated compound and compared it with intact crocin in lower dosages than other studies in AD rat models. Materials and Methods: Encapsulating crocin into chitosan nanoparticles was done through a modified technique to improve its limitations. The AD rat model was induced by bilaterally injecting beta-amyloid (Aβ) peptide into the frontal lobe using a stereotaxic device. To evaluate memory, we conducted the Barnes maze test, and to evaluate anxiety, we used the elevated plus maze test. Also, histological tests were conducted to evaluate neuronal damage in each group. Results: Crocin nano-chitosan-coated administration significantly improved specific memory indicators compared to the Aβ and other treated groups. A significant decrease in anxiety indicators was detected compared to the Aβ and other treated groups. Finally, the results of hippocampus staining indicated a meaningful difference between the Aβ group and other treated groups, compared to the crocin nano-chitosan-coated group. Conclusion: Treatment with low dosages of crocin in the nano-coated form exhibited great efficacy in reducing AD’s adverse effects compared to the same dosage of intact crocin. [ABSTRACT FROM AUTHOR]

Background and Aim: Emotion regulation is an important and determining factor in psychological wellbeing and effective behavior of people, which plays an essential role in adapting to stressful life events. People who experience emotion dysregulation may show symptoms such as impulsive behaviors, severe anxiety, aggression, and problems with metacognition. This study aims to investigate the effectiveness of high-definition transcranial direct current stimulation (HD-tDCS) in the dorsolateral prefrontal cortex (DLPFC) of the brain in improving emotion dysregulation and the speed of brain information processing. Methods: This study is pre-post-test research. In this study, 20 healthy participants (male, right-handed) were used. The participants were randomly assigned to two anodal stimulation groups and sham (control) groups. By completing the ERQ and DTS questionnaires, as well as performing the Paced Auditory Serial Addition Test (PASAT) before and after electrical stimulation of the brain by the HD-tDCS method in the L-DLPFC area, this study was followed up and carried out. Results: After the intervention (stimulation) in the pre-post test comparison between the stimulation group and the control group, there was a difference in terms of evaluation variables, suppression, being absorbed by negative emotions, regulating efforts to relieve distress, the number of correct answers in the PASAT test and the time to answer the PASAT test. There was significance (P<0.05). This shows the effectiveness of the intervention (anodal stimulation) on these components between the stimulation and control groups. However, there was no significant difference between the stimulation and control groups in terms of emotional distress tolerance, subjective estimation of distress, and the number of incorrect answers in the PASAT test (P>0.05). Also, in the comparison of the pre-post test, time was not recognized as a significant factor in any of the research components. Conclusion: High-definition transcranial direct current stimulation (HD-tDCS) in the left dorsolateral prefrontal cortex (DLPFC) improves some components of emotion dysregulation and also improves brain information processing speed. [ABSTRACT FROM AUTHOR]

The serotonin-1A receptors (5-HT1A) in the two cerebral hemispheres are differentially involved in memory. The distribution of 5-HT1A receptors in the left and right amygdala is different. Furthermore, evidence shows that the 5-HT1A receptors in the left and right amygdala work differently in memory function. The basolateral amygdala (BLA) also regulates hippocampal long-term potentiation (LTP) during stress. However, which BLA structure in each hemisphere underlies such lateralized function is unclear. The present research investigated the possible involvement of 5-HT1A lateralization in the BLA on stress-induced memory impairment. 5-HT1A receptor antagonist (Way-100-635) was injected into the left, right, or bilateral BLA twenty minutes before chronic restraint stress (CRS) for 14 consecutive days. Results indicated that suppression of 5HT1A-receptors in the BLA plays an essential role in reducing the acquisition of passive avoidance in the shuttle box test and spatial memory in the Barnes maze test in the stress animals. This decrease was significant in the CRS animals with left and bilateral suppressed 5HT1A-receptors in the BLA. Field potential recording results showed that the left, right, and bilateral injection of Way-100-635 into the BLA significantly reduced the slope and amplitude of fEPSP in the CA1 area of the hippocampus in stressed rats. No significant difference was observed in neuronal arborization in the CA1 area of the hippocampus. In conclusion, the 5-HT1A receptor in the left and right sides of BLA nuclei play a different role in memory consolidation in the hippocampus under stress. [ABSTRACT FROM AUTHOR]

Introduction: The flexibility of the heart is important for cardiovascular health. The heart rate variation (HRV) is a metric of heart flexibility. Muslims perform praying (Namaz) which has some significant effects on general health regularity. The study aimed to assess the impact of real Namaz on HRV. Materials and Methods: Eighty-two participants who performed Namaz daily were categorized into three groups, including more minor, more than, and equal to the normal cortisol level range based on salivary cortisol. The electrocardiography was recorded before, during (divided into standing, bowing, prostration, and sitting positions), and after a four-cycle Namaz around noon. The linear and non-linear features of HRV were extracted. Results: The two-way analysis of variance showed that the standard deviation (SD)1 and SD2 of the Poincare plots of all groups increased after Namaz (P<0.0001). During Namaz, the indexes of sympathetic tone decreased in the prostration and bowing compared to the sitting and standing positions (P<0.00001). The SD of the mean of the R peaks interval, SD1, and SD2 of the Poincare plot also increased in those comparisons (P<0.00001). In addition, the spectral entropy was decreased in the bowing and prostration compared with standing and sitting positions (P<0.001). Conclusion: Namaz significantly increased the performance of the cardiovascular system and decreased the effect of daily stress on it. [ABSTRACT FROM AUTHOR]

Behavioral and functional studies describe hemispheric asymmetry in anxiety and metabolic behaviors in responses to stress. However, no study has reported serotonergic receptor (the 5-HT1A receptor) lateralization in the basolateral amygdala (BLA) in vivo on anxiety and metabolic behaviors under stress. In the present study, the effect of unilateral and bilateral suppression of the 5-HT1A receptor in the BLA on anxiety, and metabolic responses to chronic restraint stress was assessed. Male Wistar rats 7 days after cannulation into the BLA received chronic restraint stress for 14 consecutive days. 20 minutes before induction of stress, WAY-100–635 (selective 5-HT1A antagonist) or sterile saline (vehicle) was administered either uni- or bi-laterally into the BLA. Behavioral (elevated plus maze; EPM, and open field test), and metabolic parameter studies were performed. Results showed that stress causes a significant increase in weight gain compared to control. In the non-stress condition, the left and bilaterally, and in the stress condition the right, left, and both sides, inhibition of 5-HT1A in the BLA reduced weight gain. In the restraint stress condition, only inhibition of the 5-HT1A receptor in the left BLA led to decreased food intake compared to the control group. In stress conditions, inhibition of the 5-HT1A receptor on the right, left, and bilateral BLA increased water intake compared to the stress group. Inhibition of the 5-HT1A receptor on the left side of the BLA by WAY-100–635 induced anxiety-like behaviors in stressed rats. Similarly, WAY-100–635 on the left BLA effectively caused anxiety-like behaviors in both EPM and open field tests in the control animals. In conclusion, it seems that 5-HT1A receptors in the left BLA are more responsible for anxiety-like behaviors and metabolic changes in responses to stress. [ABSTRACT FROM AUTHOR]

Chronic restraint stress induces anxiety‐like behaviors and emotional abnormalities via an alteration of synaptic remodeling in the amygdala and the hippocampus. Given that the date palm spathe has been shown to have neuroprotective effects on different experimental models, this study aimed to address whether the date palm spathe extract (hydroalcoholic extract of date palm spathe [HEDPP]) can reduce chronic restraint stress‐induced behavioral, electrophysiological, and morphological changes in the rat model. Thirty‐two male Wistar rats (weight 200–220 g) were randomly divided into control, stress, HEDPP, and stress + HEDPP for 14 days. Animals were submitted to restraint stress for 2 h per day for 14 consecutive days. The animals of the HEDPP and stress + HEDPP groups were supplemented with HEDPP (125 mg/kg) during these 14 days, 30 min before being placed in the restraint stress tube. We used passive avoidance, open‐field test, and field potential recording to assess emotional memory, anxiety‐like behavioral and long‐term potentiation in the CA1 region of the hippocampus, respectively. Moreover, Golgi–Cox staining was used to investigate the amygdala neuron dendritic arborization. Results showed that stress induction was associated with behavioral changes (anxiety‐like behavioral and emotional memory impairment), and the administration of HEDPP effectively normalized these deficits. HEDPP remarkably amplified the slope and amplitude of mean‐field excitatory postsynaptic potentials (fEPSPs) in the CA1 area of the hippocampus in stressed rats. Chronic restraint stress significantly decreased the dendritic arborization in the central and basolateral nucleus of the amygdala neuron. HEDPP suppressed this stress effect in the central nucleus of the amygdala. Our findings indicated that HEDPP administration improves stress‐induced learning impairment and memory and anxiety‐like behaviors by preventing adverse effects on synaptic plasticity in the hippocampus and amygdala. [ABSTRACT FROM AUTHOR]

This study aimed to compare the changes in psychological status and cortisol level between multiple sclerosis (MS) patients and a healthy control group (HC). One hundred and fifty-five MS patients and 165 HC subjects had completed questionnaires consisting of 36-Item short health survey (SF-36), Hamilton Anxiety Rating Scale (HAM-A), Beck Depression Inventory-II (BDI-II), and fatigue severity score (FSS) before and after (one year from onset) COVID-19 pandemic. The salivary cortisol level was also measured again in 26 MS patients and 14 control individuals. MS patients had lower scores of mental and physical components of quality of life (MCS and PCS), but higher HAM-A, FSS, and BDII scores than HC Before and after COVID-19. There were significant changes in scores of MCS, BDI-II, HAM-A, and FSS after the COVID-19 outbreak in MS patients, but not in PCS score. In HC group, we observed significant changes in scores of MCS, BDI-II, and FSS, but not in scores of PCS and HAM-A. Compared to HC, the MS patients reported greater deterioration in the overall mental health component of their health-related quality of life, and their levels of anxiety and fatigue over the study period. The change of cortisol levels was non-significant with a small effect size. [ABSTRACT FROM AUTHOR]

The article highlights a study on the effects of intra-ventral hippocampal memantine administration in male NMRI stressed mice were studied. It could be concluded that N-Methyl-D-aspartic acid glutamate receptors in the ventral hippocampus may play a pivotal role in the mediation of maintenance of anxiety and depression induced by stress in the mice.

Introduction: Today, humans live in a world surrounded by electromagnetic fields. Numerous studies have been conducted to discover the biological, physiological, and behavioral effects of electromagnetic fields on humans and animals. Given the biological similarities between monkeys and humans, The present research aimed to examine Visual Memory (VM), hormonal, genomic, and anatomic changes, in the male rhesus macaques exposed to an Extremely Low-Frequency Magnetic Field (ELF-MF). Methods: Four male rhesus macaques (Macaca mulatta) were used. For the behavioral tests, the animals should be fasting for 17 hours. For the tests such as visual memory, the animal's cooperation was necessary. Using the radiation protocol, we exposed two monkeys to a 12-Hz electromagnetic field with a magnitude of 0.7 µT (electromagnetic radiation) four hours a day for a month. Before and after the exposure, a visual memory test was conducted using a coated device (visible reward) on a movable stand. Ten milliliters of blood was obtained from the femoral artery of each monkey, and half of it was used to examine cortisol serum levels using the MyBioSource kit (made in the USA). The other half of the blood was used to extract lymphocytes for assaying expressions of Glucocorticoid Receptor (GR) genes before and after radiation using the PCR method. Anatomic studies of the amygdala were carried out based on pre- and post-radiation Magnetic Resonance Imaging (MRI). Results: Research results indicated that visual memory in male primates increased significantly after exposure to the 12-Hz frequency. Hormonal analysis at the 12-Hz frequency showed a decrease in cortisol serum levels. However, visual memory and serum cortisol levels did not change considerably in male primates in the control group. There was no considerable amygdala volumetric difference after exposure to the 12-Hz frequency. The expression of the GR genes decreased in the 12-Hz group compared to the control group. Conclusion: In short, these results indicated that ELF might benefit memory enhancement because exposure to the 12-HZ ELF can enhance visual memory. This outcome may be due to a decrease in plasma cortisol and or expression of GR genes. Moreover, direct amygdala involvement in this regard cannot be recommended. [ABSTRACT FROM AUTHOR]

Subclinical hypothyroidism tends to be more prevalent due to having a deficiency in iodine intake, which could lead to it. The role of sex differentiation in the susceptibility for anxiety-like behaviors of adult rats with mild neonatal hypothyroidism and then levothyroxine therapy is aimed to be investigated. Data showed that in both genders, reduced social performance and increased anxiety-like behaviors were revealed in a dose-dependent manner to propylthiouracil exposure in hypothyroid groups and levothyroxine therapy reversed the impairment performance and increased anxiety-like in the behavioral tests. Therefore, levothyroxine therapy can also be used as therapeutic methods for adult subject treatment. [ABSTRACT FROM AUTHOR]

Behavioral and functional studies describe hemispheric asymmetry in anxiety and metabolic behaviors in responses to stress. However, no study has reported serotonergic receptor (the 5-HT 1A receptor) lateralization in the basolateral amygdala (BLA) in vivo on anxiety and metabolic behaviors under stress. In the present study, the effect of unilateral and bilateral suppression of the 5-HT 1A receptor in the BLA on anxiety, and metabolic responses to chronic restraint stress was assessed. Male Wistar rats 7 days after cannulation into the BLA received chronic restraint stress for 14 consecutive days. 20 minutes before induction of stress, WAY-100-635 (selective 5-HT 1A antagonist) or sterile saline (vehicle) was administered either uni- or bi-laterally into the BLA. Behavioral (elevated plus maze; EPM, and open field test), and metabolic parameter studies were performed. Results showed that stress causes a significant increase in weight gain compared to control. In the non-stress condition, the left and bilaterally, and in the stress condition the right, left, and both sides, inhibition of 5-HT 1A in the BLA reduced weight gain. In the restraint stress condition, only inhibition of the 5-HT 1A receptor in the left BLA led to decreased food intake compared to the control group. In stress conditions, inhibition of the 5-HT 1A receptor on the right, left, and bilateral BLA increased water intake compared to the stress group. Inhibition of the 5-HT 1A receptor on the left side of the BLA by WAY-100-635 induced anxiety-like behaviors in stressed rats. Similarly, WAY-100-635 on the left BLA effectively caused anxiety-like behaviors in both EPM and open field tests in the control animals. In conclusion, it seems that 5-HT 1A receptors in the left BLA are more responsible for anxiety-like behaviors and metabolic changes in responses to stress., (© 2024. The Author(s).)