Modulation of in vivo oxidative status by exogenous corticosterone and restraint stress in rats

Impact of social isolation on corticosterone release and recovery after stroke in aged rats: A behavioral and biochemical analysis

Social isolation (SI) after stroke reduces recovery. The aim of this study was to evaluate the effects of SI on corticosterone release and recovery after stroke in aged rats. A total of 64 male Wistar rats (aged 24 months) were used in the present study. All rats were housed in pairs for two weeks. After two weeks, rats were randomly assigned to one of four groups: (1) rats underwent sham surgery and kept socially isolated (control/social isolated (CO/SI) group); (2) rats underwent sham surgery and kept pair housed (control/pair housed (CO/PH) group); (3) rats underwent middle cerebral artery occlusion (MCAO) surgery and kept socially isolated (stroke/isolated (ST/SI) group); (4) rats underwent MCAO surgery and kept pair housed (stroke/pair housed (ST/PH)) group. Behaviors were assessed using the adhesive removal test, rotarod test and social interaction test at 1st, 7th, 14th and 21st days after stroke. Serum biochemical analysis was also performed on the behavioral testing days. Results showed THAT serum corticosterone and MDA levels in CO/PH group were significantly lower than CO/SI group. Serum BDNF levels in CO/PH group was significantly higher than CO/SI group. Serum corticosterone and MDA levels in ST/PH group were lower than ST/SI group. In ST/PH group, serum Total antioxidant capacity (TAC) and BDNF levels were significantly higher than ST/SI group. Biochemical analysis of certain regions of the brain (hippocampus, striatum and cerebral cortex) was performed on 21st day after stroke. In the hippocampus of CO/PH group, BDNF and TAC levels were significantly higher than CO/SI group. The hippocampal MDA level of CO/PH group were significantly lower than CO/SI group. BDNF and TAC levels in the hippocampus, striatum and cerebral cortex of ST/PH group were significantly higher and MDA level was significantly lower as compared with ST/SI group. Both ischemic groups showed sensorimotor recovery over a 21-day period, but recovery of ST/PH group was significantly greater than ST/SI group. Total social interaction time in ST/PH group was significantly longer than ST/SI group. Based on the results of this study, social interaction after stroke enhances histologic and sensorimotor recovery through reduction of HPA activity and corticosterone release, leading to increased TAC and BDNF levels.

Current Aspects of Selected Factors to Modulate Brain Health and Sports Performance in Athletes

This review offers a comprehensive evaluation of current aspects related to nutritional strategies, brain modulation, and muscle recovery, focusing on their applications and the underlying mechanisms of physiological adaptation for promoting a healthy brain, not only in athletes but also for recreationally active and inactive individuals. We propose that applying the rule, among others, of good sleep, regular exercise, and a properly balanced diet, defined as "SPARKS", will have a beneficial effect on the function and regeneration processes of the gut-brain-muscle axis. However, adopting the formula, among others, of poor sleep, stress, overtraining, and dysbiosis, defined as "SMOULDER", will have a detrimental impact on the function of this axis and consequently on human health as well as on athletes. Understanding these dynamics is crucial for optimizing brain health and cognitive function. This review highlights the significance of these factors for overall well-being, suggesting that adopting the "SPARKS" approach may benefit not only athletes but also older adults and individuals with health conditions.

Glomerular Hypertrophy and Splenic Red Pulp Degeneration Concurrent with Oxidative Stress in 3xTg-AD Mice Model for Alzheimer's Disease and Its Exacerbation with Sex and Social Isolation

The continuously expanding field of Alzheimer's disease (AD) research is now beginning to defocus the brain to take a more systemic approach to the disease, as alterations in the peripheral organs could be related to disease progression. One emerging hypothesis is organ involvement in the process of Aβ clearance. In the present work, we aimed to examine the status and involvement of the kidney as a key organ for waste elimination and the spleen, which is in charge of filtering the blood and producing lymphocytes, and their influence on AD. The results showed morphological and structural changes due to acute amyloidosis in the kidney (glomeruli area) and spleen (red pulp area and red/white pulp ratio) together with reduced antioxidant defense activity (GPx) in 16-month-old male and female 3xTg-AD mice when compared to their age- and sex-matched non-transgenic (NTg) counterparts. All these alterations correlated with the anxious-like behavioral phenotype of this mouse model. In addition, forced isolation, a cause of psychological stress, had a negative effect by intensifying genotype differences and causing differences to appear in NTg animals. This study further supports the relevance of a more integrative view of the complex interplay between systems in aging, especially at advanced stages of Alzheimer's disease.

Exploring the gut microbiota-hippocampus-metabolites axis dysregulation in sepsis mice

Background

Sepsis is commonly associated with a sudden impairment of brain function, thus leading to significant rates of illness and mortality. The objective of this research was to integrate microbiome and metabolome to reveal the mechanism of microbiota-hippocampus-metabolites axis dysfunction in a mouse model of sepsis.

Methods

A mouse model of sepsis was established via cecal ligation and puncture. The potential associations between the composition of the gut microbiota and metabolites in the hippocampus of mice with sepsis were investigated by combining 16S ribosomal RNA gene sequencing and ultra-high-performance liquid chromatography tandem mass spectrometry.

Results

A total of 140 differential metabolites were identified in the hippocampal tissues of mice with sepsis when compared to those of control mice. These differential metabolites in mice with sepsis were not only associated with autophagy and serotonergic synapse, but also involved in the metabolism and synthesis of numerous amino acids. At the phylum level, the abundance of Bacteroidota was increased, while that of Firmicutes (Bacillota) was decreased in mice with sepsis. At the genus level, the abundance of Alistipes was increased, while that of Lachnospiraceae_NK4A136_group was decreased in mice with sepsis. The Firmicutes (Bacillota)/Bacteroidota (F/B) ratio was decreased in mice with sepsis when compared to that of control mice. Furthermore, the F/B ratio was positively correlated with 5'-methylthioadenosine, PC (18:3(9Z,12Z,15Z)/18:0) and curdione, and negatively correlated with indoxylsulfuric acid, corticosterone, kynurenine and ornithine.

Conclusion

Analysis revealed a reduction in the F/B ratio in mice with sepsis, thus contributing to the disturbance of 5'-methylthioadenosine, curdione, PC (18:3(9Z,12Z,15Z)/18:0), corticosterone, ornithine, indoxylsulfuric acid and kynurenine; eventually, these changes led to hippocampus dysfunction. Our findings provide a new direction for the management of sepsis-induced hippocampus dysfunction.

Anthropogenic and climatic factors interact to influence reproductive timing and effort

Reproduction, although absolutely essential to a species' persistence, is in itself challenging. As anthropogenic change increasingly affects every landscape on Earth, it is critical to understand how specific pressures impact the reproductive efforts of individuals, which directly contribute to the success or failure of populations. However, organisms rarely encounter a single burden at a time, and the interactions of environmental challenges can have compounding effects. Understanding environmental and physiological pressures is difficult because they are often context-dependent and not generalizable, but long-term monitoring across variable landscapes and weather patterns can improve our understanding of these complex interactions. We tested the effects of urbanization, climate, and individual condition on the reproductive investment of wild side-blotched lizards (Uta stansburiana) by measuring physiological/reproductive metrics from six populations in urban and rural areas over six consecutive years of variable precipitation. We observed that reproductive stage affected body condition, corticosterone concentration, and oxidative stress. We also observed that reproductive patterns differed between urban and rural populations depending on rainfall, with rural animals increasing reproductive investment during rainier years compared to urban conspecifics, and that reproductive decisions appeared to occur early in the reproductive process. These results demonstrate the plastic nature of a generalist species optimizing lifetime fitness under varying conditions.

Anethole as a promising antidepressant for maternal separation stress in mice by modulating oxidative stress and nitrite imbalance

The occurrence of major depressive disorder is widespread and can be observed in individuals belonging to all societies. It has been suggested that changes in the NO pathway and heightened oxidative stress may play a role in developing this condition. Anethole is a diterpene aromatic compound found in the Umbelliferae, Apiaceae, and Schisandraceae families. It has potential pharmacological effects like antioxidant, anxiolytic, analgesic, anti-inflammatory, antidiabetic, gastroprotective, anticancer, estrogenic, and antimicrobial activities. This study aimed to investigate the potential antidepressant properties of Anethole in a mouse model experiencing maternal separation stress while also examining its impact on oxidative stress and nitrite levels. The research involved the participation of 40 male NMRI mice, separated into five distinct groups to conduct the study. The control group was administered 1 ml/kg of normal saline, while the MS groups were given normal saline and Anethole at 10, 50, and 100 mg/kg doses. The study comprised various behavioural tests, including the open field test (OFT), forced swimming test (FST), and splash test, to assess the effects of Anethole on the mice. In addition to the behavioural tests, measurements were taken to evaluate the total antioxidant capacity (TAC), malondialdehyde (MDA), and nitrite levels in the hippocampus of the mice. According to the findings, maternal separation stress (MS) led to depressive-like conduct in mice, including a rise in immobility duration during the FST and a reduction in the duration of grooming behaviour in the splash test. Additionally, the results indicated that MS correlated with an increase in the levels of MDA and nitrite and a reduction in the TAC in the hippocampus. However, the administration of Anethole resulted in an increase in grooming activity time during the splash test and a decrease in immobility time during the FST. Anethole also exhibited antioxidant characteristics, as demonstrated by its ability to lower MDA and nitrite levels while increasing the TAC in the hippocampus. The results suggest that Anethole may have an antidepressant-like impact on mice separated from their mothers, likely partly due to its antioxidant properties in the hippocampus.

Clinical and cardiac characteristics of primary bilateral macronodular adrenal hyperplasia

Background

Cardiovascular disease is the leading cause of death in Cushingžs syndrome (CS). Primary bilateral macro-nodular adrenal hyperplasia (PBMAH), is a rare cause of CS that is clinically distinct from the other common types of CS, but cardiac characteristics have been poorly studied.

Methods

The clinical data, steroid hormones and echocardiographic variables of 17 patients with PBMAH were collected. Twenty-one CS patients with cortisol-producing adenoma (CPA) were collected as controls. The similarities and differences of clinical and cardiac features between the two groups were compared.

Vitamin E reduces oxidative stress in brains of male albino male rats undergoing immobilization

Stress can lead to various health problems. Exposure to stress is linked to several diseases including cancer, hypertension, diabetes, mental disorders, and heart attacks. Stress stimulates several pathways that produce free radicals, which increases oxidative stress. This results in functional and structural damage to organs, such as the brain, which is highly sensitive to oxidative stress Vitamin E is a naturally occurring potent antioxidant used for various purposes. The main purpose of the current study was to evaluate how vitamin E protects the brain and to what extent it affects antioxidant levels in rats subjected to two hours per day of immobilization stress, the form of stress with the strongest effect. The rats were immobilized by folding their limbs in and wrapping them in netting to prevent movement, while allowing their tails to be extended. The rats were then hung upside down. The effect of vitamin E was tested by intraperitoneally injecting rats with 40 mg/kg of vitamin E daily. Oxidative stress parameters were determined at the completion of the experiment. A dramatic decrease in malondialdehyde (MDA) levels and an increase in catalase (CAT), including glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD), has been shown by vitamin E in the brain. The effects of vitamin E were significantly higher in the acute and chronic stress groups than in the control group. Vitamin E can decrease oxidative stress in stressed rats, indicating that it exerts therapeutic and protective effects owing to its antioxidant properties.

Effects of unpredictable chronic mild stress on the cellular redox state and mitochondrial energy homeostasis in rat adipose tissue: A comprehensive metabolic study

Unpredictable chronic mild stress (UCMS) leads to variable metabolic effects. Oxidative stress (OS) of adipose tissue (AT) and mitochondrial energy homeostasis is little investigated. This work studied the effects of UCMS on OS and the antioxidant/redox status in AT and mitochondrial energy homeostasis in rats. Twenty-four male Wistar rats (180-220 g) were divided into two equal groups; the normal control (NC) group and the UCMS group which were exposed to various stresses for 28 days. An indirect calorimetry machine was used to measure volumes of respiratory gases (VO2 & VCO2 ), total energy expenditure (TEE), and food intake (FI). The AT depots were collected, weighed, and used for measuring activities and gene expression of key antioxidant enzymes (GPx1, SOD, CAT, GR, GCL, and GS), OS marker levels including superoxide anion (SA), peroxynitrite radical (PON), nitric oxide (NO), hydrogen peroxide (H2 O2 ), lipid peroxides (LPO), t-protein carbonyl content (PCC), and reduced/oxidized glutathione levels (GSH, GSSG). Additionally, AT mitochondrial fractions were used to determine the activities of the tricarboxylic acid cycle (TCA) cycle enzymes (CS, α-KGDH, ICDH, SDH, MDH), respiratory chain complexes I-III, II-III, IV, the nicotinamide coenzymes NAD+ , NADH, and ATP/ADP levels. Compared with the NC group, the UCMS group showed very significantly increased OS marker levels, lowered antioxidant enzyme activities and gene expression, as well as lowered TCA cycle and respiratory chain activity and NAD+ , NADH, and ATP levels (p < .001 for all comparisons). Besides, the UCMS group had lowered TEE and insignificant FI and weight gain. In conclusion, AT of the UCMS-subjected rats showed a state of disturbed redox balance linked to disrupted energy homeostasis producing augmentation of AT.

Nrf2 regulates iron-dependent hippocampal synapses and functional connectivity damage in depression

Neuronal iron overload contributes to synaptic damage and neuropsychiatric disorders. However, the molecular mechanisms underlying iron deposition in depression remain largely unexplored. Our study aims to investigate how nuclear factor-erythroid 2 (NF-E2)-related factor 2 (Nrf2) ameliorates hippocampal synaptic dysfunction and reduces brain functional connectivity (FC) associated with excessive iron in depression. We treated mice with chronic unpredictable mild stress (CUMS) with the iron chelator deferoxamine mesylate (DFOM) and a high-iron diet (2.5% carbonyl iron) to examine the role of iron overload in synaptic plasticity. The involvement of Nrf2 in iron metabolism and brain function was assessed using molecular biological techniques and in vivo resting-state functional magnetic resonance imaging (rs-fMRI) through genetic deletion or pharmacologic activation of Nrf2. The results demonstrated a significant correlation between elevated serum iron levels and impaired hippocampal functional connectivity (FC), which contributed to the development of depression-induced CUMS. Iron overload plays a crucial role in CUMS-induced depression and synaptic dysfunction, as evidenced by the therapeutic effects of a high-iron diet and DFOM. The observed iron overload in this study was associated with decreased Nrf2 levels and increased expression of transferrin receptors (TfR). Notably, inhibition of iron accumulation effectively attenuated CUMS-induced synaptic damage mediated by downregulation of brain-derived neurotrophic factor (BDNF). Nrf2-/- mice exhibited compromised FC within the limbic system and the basal ganglia, particularly in the hippocampus, and inhibition of iron accumulation effectively attenuated CUMS-induced synaptic damage mediated by downregulation of brain-derived neurotrophic factor (BDNF). Activation of Nrf2 restored iron homeostasis and reversed vulnerability to depression. Mechanistically, we further identified that Nrf2 deletion promoted iron overload via upregulation of TfR and downregulation of ferritin light chain (FtL), leading to BDNF-mediated synapse damage in the hippocampus. Therefore, our findings unveil a novel role for Nrf2 in regulating iron homeostasis while providing mechanistic insights into poststress susceptibility to depression. Targeting Nrf2-mediated iron metabolism may offer promising strategies for developing more effective antidepressant therapies.

Functional Additives in a Selected European Sea Bass (Dicentrarchus labrax) Genotype: Effects on the Stress Response and Gill Antioxidant Response to Hydrogen Peroxide (H2O2) Treatment

Functional ingredients have profiled as suitable candidates for reinforcing the fish antioxidant response and stress tolerance. In addition, selective breeding strategies have also demonstrated a correlation between fish growth performance and susceptibility to stressful culture conditions as a key component in species domestication processes. The aim of the present study is to evaluate the ability of a selected high-growth genotype of 300 days post-hatch European sea bass (Dicentrarchus labrax) juveniles to use different functional additives as endogenous antioxidant capacity and stress resistance boosters when supplemented in low fish meal (FM) and fish oil (FO) diets. Three isoenergetic and isonitrogenous diets (10% FM/6% FO) were supplemented with 200 ppm of a blend of garlic and Labiatae plant oils (PHYTO0.02), 1000 ppm of a mixture of citrus flavonoids and Asteraceae and Labiatae plant essential oils (PHYTO0.1) or 5000 ppm of galactomannan-oligosaccharides (GMOS0.5). A reference diet was void of supplementation. The fish were fed the experimental diets for 72 days and subjected to a H₂O₂ exposure oxidative stress challenge. The fish stress response was evaluated through measuring the circulating plasma cortisol levels and the fish gill antioxidant response by the relative gene expression analysis of nfΚβ2, il-1b, hif-1a, nd5, cyb, cox, sod, cat, gpx, tnf-1α and caspase 9. After the oxidative stress challenge, the genotype origin determined the capacity of the recovery of basal cortisol levels after an acute stress response, presenting GS fish with a better pattern of recovery. All functional diets induced a significant upregulation of cat gill gene expression levels compared to fish fed the control diet, regardless of the fish genotype. Altogether, suggesting an increased capacity of the growth selected European sea bass genotype to cope with the potential negative side-effects associated to an H₂O₂ bath exposure.

ILF3 prion-like domain regulates gene expression and fear memory under chronic stress

The prion-like domain (PrLD) is a class of intrinsically disordered regions. Although its propensity to form condensates has been studied in the context of neurodegenerative diseases, the physiological role of PrLD remains unclear. Here, we investigated the role of PrLD in the RNA-binding protein NFAR2, generated by a splicing variant of the Ilf3 gene. Removal of the PrLD in mice did not impair the function of NFAR2 required for survival, but did affect the responses to chronic water immersion and restraint stress (WIRS). The PrLD was required for WIRS-sensitive nuclear localization of NFAR2 and WIRS-induced changes in mRNA expression and translation in the amygdala, a fear-related brain region. Consistently, the PrLD conferred resistance to WIRS in fear-associated memory formation. Our study provides insights into the PrLD-dependent role of NFAR2 for chronic stress adaptation in the brain.

Chronic stress decreases fertility parameters in female rats

Multiple effects of stress on health have been reported; however, reproductive alterations in oocytes and cumulus cells have not been fully described. In females, chronic stress has been shown to produce alterations in the estrous cycle, to decrease oocyte in vivo maturation, and to increase the percentage of abnormal oocytes. The aim of this study was to evaluate whether the oocytes from chronically stressed female rats could recover and mature in vitro by providing them with all the necessary culture conditions, as well as to evaluate the functionality of the GAP junctions, and the viability and DNA integrity of the cumulus cells, which are crucial for the complete maturation and development of the oocyte. For this, rats were stressed daily by cold water immersion (15 °C) during 15 min for 30 consecutive days. Corticosterone serum levels in rats increased as an indicator of stress. Chronic stress decreased the percentage of in vitro matured oocytes because the cumulus cells presented irreparable damage to their DNA that led to their death, being unable to establish bidirectional communication with the oocyte for its meiotic resumption through the GAP junctions, which were also damaged. These findings could partially explain an association between stress and infertility.

Increases in serum carbonylated protein levels of dogs with hypercortisolism

Protein carbonylation is an irreversible and degenerative modification that can be used to evaluate oxidative stress caused by glucocorticoids. In this study, we focused on protein carbonylation in dogs with hypercortisolism (HC). Sera samples were collected from 14 dogs diagnosed with HC and treated with trilostane, 12 dogs with inflammatory diseases (disease control group), and eight clinically healthy dogs. When the carbonylated protein levels were detected by the immunoblot analysis, one band of approximately 40 kDa was predominantly increased in the dogs with HC. The band was identified as haptoglobin using the liquid chromatography tandem mass spectrometry method. Furthermore, haptoglobin immune reactivity was higher in the dogs with HC. Although the average protein carbonylation level of the HC group was not significantly different from that of the other groups, the carbonylation level was significantly higher for the poorly controlled HC cases than for the well-controlled HC group. Additionally, the primary culture of canine hepatocytes was used to clarify the direct effect of glucocorticoids on protein carbonylation in dog livers. Both the carbonylated protein and haptoglobin clearly increased after 72 h. These findings suggest that haptoglobin and its carbonylated form are increased with canine HC, and that the protein carbonylation ratio and/or haptoglobin level could be related to disease management. These factors could be useful as biomarkers for an oxidative stress reaction, at least in the liver, and for treatment monitoring of HC.

Chronic clomipramine treatment reverses depressogenic-like effects of a chronic treatment with dexamethasone in rats

Corticosteroids are widely used in medicine, for their anti-inflammatory and immunosuppressive actions, but can lead to troubling psychiatric side-effects. In fact, corticosteroids can induce many symptoms and syndromes, for example, mood disorders, anxiety and panic disorder, suicidal thinking and behavior. Furthermore, chronic stress and the administration of exogenous glucocorticoids are reported to induce affective changes in humans and rodents that relate to depressive state. Animal models are highly useful tools for studying the depression etiology. Face validity, construct validity, and predictive validity are the main criteria to evaluate animal depression models. The present study aimed to investigate the behavioral, cognitive, and biochemical effects of a chronic administration of DEX on Wistar rats. Wistar rats were administered daily with DEX (1.5 mg/kg, i.p., 21 days) or saline, the clomipramine treatment (2 mg/kg, i.p.) was realized just after the DEX injections for 21 days. DEX induced changes were evaluated by: forced swimming, novelty suppressed feeding, saccharin preference, open field, Morris water maze, and oxidative stress state in the brain. Results showed that chronic DEX administration conduct to a range of depression-related behavioral traits, including anhedonia, despair, weight loss, anxiety-like behavior, and cognitive impairments, which fill the face validity criterion. The DEX induced behavioral changes may result from the massive production of oxidative stress agents. This sustains the etiological hypothesis claiming that hyper-circulating glucocorticoid resulting from HPA dysfunction induces damage in certain neural structures related to depressive disorder, essentially the hippocampus. The antidepressant treatment has restored the behavioral state of rats which fills the predictive validity criterion.

Differentiating metabolomic responses of amphibians to multiple stressors

One of the biggest challenges in ecological risk assessment is determining the impact of multiple stressors on individual organisms and populations in real world scenarios. Frequently, data derived from laboratory studies of single stressors are used to estimate risk parameters and do not adequately address scenarios where other stressors exist. Emerging 'omic technologies, notably metabolomics, provide an opportunity to address the uncertainties surrounding ecological risk assessment of multiple stressors. The objective of this study was to use metabolomic profiling to investigate the effect of multiple stressors on amphibian metamorphs. We exposed post-metamorphosis (180 days) southern leopard frogs (Lithobates sphenocephala) to the insecticide carbaryl (480 μg/L), predation stress, and a combined pesticide and predation stress treatment. Corticosterone analysis revealed mild support for an induction in response to predation stress alone but strongly suggests that carbaryl exposure, alone or in combination with predation cues, can significantly elevate this known biomarker in amphibians. Metabolomics analysis accurately classed, based on relative nearness, carbaryl and predation induced changes in the hepatic metabolome and biochemical fluxes appear to be associated with a similar biological response. Support vector machine analysis with recursive feature elimination of the acquired metabolomic spectra demonstrated 85-96% classification accuracy among control and all treatment groups when using the top 75 ranked retention time bins. Biochemical fluxes observed in the groups exposed to carbaryl, predation, and the combined treatment include amino acids, sugar derivatives, and purine nucleotides. Ultimately, this methodology could be used to interpret short-term toxicity assays and the presence of environmental stressors to overall metabolomic effects in non-target organisms.

Probiotics (Bacillus clausii and Lactobacillus fermentum NMCC-14) Ameliorate Stress Behavior in Mice by Increasing Monoamine Levels and mRNA Expression of Dopamine Receptors (D1 and D2) and Synaptophysin

Stress is a physiological consequence of the body to adversity. The gut–brain axis and probiotics are gaining interest to provide better treatment for stress and other neurological disorders. Probiotic (Lactobacillus fermentum NMCC-14 and Bacillus clausii, 1010 colony-forming unit/day/animal, per oral) effects were investigated in acute (up to day 7) and subacute (days 8–14) restraint-stressed and normal mice through behavioral paradigms (elevated plus maze: EPM, light dark box/dark light box: LDB, and open field test: OFT). Time spent in the open arms of the EPM, time spent in the light compartment of the LDB, and movable time and time spent in the center of the OFT were significantly (p ≤ 0.05, n = 5) increased in probiotic-treated restraint-stressed mice. Enzyme-linked immunoassay determined blood cortisol and adrenocorticotropic hormone (ACTH) levels, which were reduced significantly (p &lt; 0.05, n = 5) in probiotic-treated restraint-stressed mice. Hematoxylin and eosin-stained hippocampal slides also showed less or no neurodegeneration in the probiotic-treated animals. High-performance liquid chromatography and quantitative polymerase chain reaction were performed to determine the monoamine levels and mRNA expression of dopamine receptor subtypes (D1 and D2) and synaptophysin in the mice hippocampus (HC) and prefrontal cortex (PFC). The dopamine, serotonin, and norepinephrine levels were also significantly (p &lt; 0.05, n = 5) increased in the HC and PFC of probiotic-treated animal brains. Fold expression of mRNA of D1 and D2 (except HC, LF-S, day 14) receptors and synaptophysin was also significantly (p &lt; 0.05, n = 5) increased in the same brain parts of probiotic-treated restraint-stressed mice. Comparing mice in the Lactobacillus fermentum NMCC-14 and Bacillus clausii groups to mice in the normal group, only a significant (p &lt; 0.05, n = 5) decrease was observed in the serum ACTH and cortisol levels on day 14 in Bacillus clausii-treated mice, where all other parameters also showed improvement. In comparison, Bacillus clausii showed greater stress suppressant activity than Lactobacillus fermentum NMCC-14. However, both probiotic bacteria can be a better and safer therapeutic alternative for ailments than currently available drugs.

Neurobiological Links between Stress, Brain Injury, and Disease

Stress, which refers to a combination of physiological, neuroendocrine, behavioral, and emotional responses to novel or threatening stimuli, is essentially a defensive adaptation under physiological conditions. However, strong and long-lasting stress can lead to psychological and pathological damage. Growing evidence suggests that patients suffering from mild and moderate brain injuries and diseases often show severe neurological dysfunction and experience severe and persistent stressful events or environmental stimuli, whether in the acute, subacute, or recovery stage. Previous studies have shown that stress has a remarkable influence on key brain regions and brain diseases. The mechanisms through which stress affects the brain are diverse, including activation of endoplasmic reticulum stress (ERS), apoptosis, oxidative stress, and excitatory/inhibitory neuron imbalance, and may lead to behavioral and cognitive deficits. The impact of stress on brain diseases is complex and involves impediment of recovery, aggravation of cognitive impairment, and neurodegeneration. This review summarizes various stress models and their applications and then discusses the effects and mechanisms of stress on key brain regions—including the hippocampus, hypothalamus, amygdala, and prefrontal cortex—and in brain injuries and diseases—including Alzheimer’s disease, stroke, traumatic brain injury, and epilepsy. Lastly, this review highlights psychological interventions and potential therapeutic targets for patients with brain injuries and diseases who experience severe and persistent stressful events.

Protective effect of Myrcia pubipetala Miq. against the alterations in oxidative stress parameters in an animal model of depression induced by corticosterone

Depression is a debilitating disorder in humans that significantly affects quality of life. As such, alternative therapies are highly sought after by patients seeking treatment for depression. Experimentally, the chronic administration of corticosterone (CORT) in rodents has been reported to promote depressive-like behaviors. Herein, animals received saline or CORT for 21 days and, during the last 7 days, they were treated with the crude hydroalcoholic extract (CHE) of Myrcia pubipetala Miq (50, 100 or 150 mg/Kg), or vehicle (distilled water), by oral route. After 24 h, animals were subjected to the open field (OFT) and forced swimming tests (FST), and then sacrificed for the removal of the hippocampus and cerebral cortex for biochemical analysis. Results showed enhanced catalase (CAT) and superoxide dismutase (SOD) activities, as well as an elevated formation of thiobarbituric acid reactive substances (TBARS), in the cerebral cortex of CORT-treated mice. The chronic administration of the CHE (100 and 150 mg/Kg) reduced TBARS and the increased total sulfhydryl content, and also reversed the increase in TBARS induced by CORT. In the hippocampus, CORT increased CAT and SOD activities and reduced glutathione peroxidase (GSH-Px) (C) activity, while Myrcia pubipetala Miq. CHE (100 and 150 mg/Kg) increased GSH-Px activity when administered alone and reversed decreased GSH-Px (100 and 150 mg/Kg) activity when given during CORT administration. Neither CORT administration nor CHE treatment significantly altered the immobility time of the animals in FST and no changes were observed in the locomotor activity of the animals in the OFT. Findings indicate that the CHE of Myrcia pubipetala Miq. exerts antioxidant effects in the cerebral cortex and hippocampus of mice induced to depression by CORT. Since phenolic compounds are reported to have antioxidant effects in this species, the effects of the CHE may be, at least in part, mediated by the presence of these compounds in Myrcia extract.

Protective effect of mitophagy against aluminum-induced MC3T3-E1 cells dysfunction

Aluminum (Al) is a ubiquitous environmental metal toxicant that causes osteoblast (OB) damage which leads to Al-related bone diseases. Mitochondrial damage plays a key role in Al-related bone diseases, and while mitophagy can clear damaged mitochondria and improve OB function, the relationship between mitophagy and Al-induced OB dysfunction is unknown. To explore the role of mitophagy in Al-induced OB dysfunction in vitro, we used 2 μM carbonyl cyanide m-chlorophenylhydrazone (CCCP) and 0.4 μM Cyclosporin A (CsA) to activate and inhibit mitophagy, respectively. MC3T3-E1 cells were treated with 0 mM AlCl₃ (control group); 2 mM AlCl₃ (Al group); 2 μM CCCP (CCCP group); 2 μM CCCP and 2 mM AlCl₃ (CCCP + Al group); 0.4 μM CsA (CsA group); 0.4 μM CsA and 2 mM AlCl₃ (CsA + Al group). The results showed that Al induced ultrastructural and functional impairment of MC3T3-E1 cells. Compared to the Al group, mitophagy activation caused mitochondrial membrane potentials to collapse, up-regulated PINK1, Parkin, and LC3 expression, down-regulated p62 expression, and increased mitophagosome numbers. Mitophagy activation also reduced Al-induced oxidative stress and MC3T3-E1 cell functional damage, as seen in improvement in cell viability, cellular calcium and phosphorus contents, and collagen I, osteocalcin, and bone alkaline phosphatase gene expression. Mitophagy inhibition had the opposite effects on activation. Overall, these results show that mitophagy can protect against Al-induced OB dysfunction.

Antidepressant effect of catalpol on corticosterone-induced depressive-like behavior involves the inhibition of HPA axis hyperactivity, central inflammation and oxidative damage probably via dual regulation of NF-κB and Nrf2

This study aimed to investigate the antidepressant effect and mechanism of catalpol on corticosterone (CORT)-induced depressive-like behavior in mice for the first time. As a result, CORT injection induced depressive-like behaviors of mice in behavioral tests, aggravated the serum CORT, adrenocorticotropic hormone, and corticotropin-releasing hormone levels, and conspicuously elevated the phosphorylations of nuclear factor kappa-B (NF-κB) in the hippocampus and frontal cortex, and down-regulated the expression levels of nuclear factor erythroid-2-related factor 2 (Nrf2). Furthermore, CORT exposure dramatically augmented the levels of inflammatory factors (interleukin-1β, tumor necrosis factor-α, nitric oxide synthase, and nitric oxide) and lipid peroxidation product malondialdehyde, and attenuated the levels of antioxidants including reduced glutathione, glutathione S-transferase, total superoxide dismutase, and heme oxygenase-1 in the mouse hippocampus and frontal cortex. On the contrary, catalpol administration markedly suppressed the abnormalities of the above indicators. From the overall results, this study displayed that catalpol exerted a beneficial effect on CORT-induced depressive-like behavior in mice possibly via the inhibition of hypothalamus-pituitary-adrenal (HPA) axis hyperactivity, central inflammation and oxidative damage at least partially through dual regulation of NF-κB and Nrf2.

Differential response of diurnal and nocturnal mammals to prolonged altered light-dark cycle: a possible role of mood associated endocrine, inflammatory and antioxidant system

The circadian system maintains internal 24 h oscillation of behavior and physiology, and its misalignment with external light-dark (LD) cycle results in negative health outcomes. In order to elucidate the effect of prolonged constant condition and the differences in the response between nocturnal and diurnal species, we studied the effects of constant light (LL) and constant darkness (DD) on a diurnal (squirrel) and a nocturnal (mouse) rodent species, focusing on the endocrine, inflammatory and antioxidant systems associated with depression-like behavior. Squirrels and mice (n = 10/group) were placed in chronocubicle under 12:12 h LD cycle, LL and DD. After 4 weeks, animals were subjected to sucrose preference test and blood and brain tissues were collected for measuring melatonin, corticosterone, proinflammatory cytokine, tumor necrosis factor-α (TNF-α) and the activity of primary antioxidant enzymes, catalase (CAT) and superoxide dismutase (SOD). The results show that in diurnal squirrels, prolonged constant darkness reduced sucrose preference, CAT, and SOD, increased corticosterone and TNF-α levels, but caused no significant change in the melatonin compared to LD condition. In contrast, in nocturnal mice constant darkness caused no significant changes in sucrose preference and corticosterone levels, increased melatonin, CAT and SOD levels but decreased TNF-α levels. Chronic LL caused a similar response in both squirrels and mice: it decreased sucrose preference, melatonin, CAT and SOD levels but increased corticosterone and TNF-α levels. Together, the study demonstrates differential effects of altered light-dark cycle in a diurnal and a nocturnal rodent on interrelated endocrine, inflammatory and antioxidant systems associated with depression-like behavior, with constant light having adverse effects on both species but constant darkness having a negative effect mainly in the diurnal squirrels.

Protective role of Allium cepa Linn (onion) juice on maternal dexamethasone induced alterations in reproductive functions of female offspring of Wistar rats

Maternal treatment with dexamethasone induces oxidative stress in the reproductive structures of offspring. Consumption of Allium cepa Linn improves antioxidant status. This study was designed to evaluate the protective role of Allium cepa Linn juice on maternal dexamethasone induced alterations in reproductive functions of the female offspring of Wistar rats. Twenty lactating dams (180-200 ​g) were randomly assigned into four groups (n ​= ​5) on the day of parturition and treated as follows during lactation for 21 days: Control (5 ​ml/kg BW distilled water); Dexamethasone (60 ​μg/kg BW); Allium cepa (5 ​ml/kg BW); Dexamethasone ​+ ​Allium cepa (60 ​μg/kg BW ​+ ​5 ​ml/kg BW). The female offspring were separated at birth. Days of vaginal opening and first oestrus cycle, length and frequency of estrous cycle as well as serum hormonal profiles were assessed as measure of reproductive functions. Ovarian superoxide dismutase (SOD) activity, catalase activity and malondialdehyde (MDA) level were measured as indices of oxidative stress. Oestrous cycle length, frequencies of diestrus as well as the Ovarian MDA were significantly increased (p ​< ​0.05) in dexamethasone (DEX) group relative to control group. Serum 17β-oestradiol and corticosterone level in addition to SOD and catalase activities were significantly reduced (p ​< ​0.05) in DEX group relative to control. Co-administration of Dex with Allium cepa Linn juice reduced the oestrous length, frequency of diestrous as well as ovarian MDA. There was also a significant increase in serum 17β-oestradiol, ovarian SOD and catalase activity. The results suggest that Allium cepa could protect against alterations in reproductive functions of offspring induced by maternal treatment with dexamethasone during lactation in Wistar rats. The flavonoid constituent of onion may also help in reducing oxidative stress in the offspring.

Chronic unpredictable stress negatively regulates hippocampal neurogenesis and promote anxious depression-like behavior via upregulating apoptosis and inflammatory signals in adult rats

Psychological and physical stress play a pivotal role in etiology of anxiety and depression. Chronic psychological and physical stress modify various physiological phenomena, as a consequence of which oxidative stress, decreased neurotransmitter level, elevated corticosterone level and altered NSC homeostasis is observed. However, the precise mechanism by which chronic stress induce anxious depression and modify internal milieu is still unknown. Herein, we show that exposure to CUS increase oxidative stress, microgliosis, astrogliosis while it reduces hippocampal NSC proliferation, neuronal differentiation and maturation in adult rats. CUS exposure in rats reduce dopamine and serotonin level in cortex and hippocampus, which result in increased anxiety and depression-like phenotypes. We also found elevated level of NF-κB and TNF-α while decreased anti-inflammatory cytokine IL-10 level, that led to increased expression of Bax and cleaved Caspase-3 whereas down regulation of antiapoptotic protein Bcl2. Additionally, CUS altered adult hippocampal neurogenesis, increased gliosis and neuronal apoptosis in cerebral cortex and hippocampus which might be associated with reduced AKT and increased ERK signaling, as seen in the rat brain tissue. Taken together, these results indicate that CUS induce oxidative stress and neuroinflammation which directly affects NSC dynamics, monoamines levels and behavioral functions in adult rats.

Protective effects of duloxetine against chronic immobilisation stress-induced anxiety, depression, cognitive impairment and neurodegeneration in mice

OBJECTIVES

This study aimed to evaluate the effect of duloxetine (10 and 20 mg/kg) against chronic immobilisation stress (CIS)-induced anxiety, depression, cognitive impairment and neurodegeneration in mice.

METHODS

CIS, 2 h/10 days (11:00 AM-1:00 PM) was applied after 30 min of pretreatment with saline, duloxetine 10 mg/kg and 20 mg/kg to the respective groups of animals, except the control group. Animals were examined for physiological (body weight, locomotion and grip strength), psychological (memory impairment, anxiety and depression), neurochemical (GABA and glutamate), biochemical (MDA, catalase, glutathione, superoxide dismutase) and histopathological changes.

KEY FINDINGS

CIS exposure revealed anxiety-like behaviour, depression-like behaviour, motor in-coordination and learning and memory impairment in mice. Besides, CIS induction decreased the antioxidant enzymes (GSH, SOD and catalase), GABA and the viable neuronal cell count, whereas CIS exposure significantly elevated the MDA, AChE activity and glutamate content in the cortex and hippocampus. Pretreatment with duloxetine10 and 20 mg/kg showed dose-dependent ameliorated effect against the CIS-induced alterations in mice.

CONCLUSION

In conclusion, the results of this study demonstrated the protective effect of duloxetine against neuropsychiatric symptoms, memory impairment caused by CIS-induction through inhibition of oxidative stress, AChE activity and glutamate release.

The Role of the FOXO1/β2-AR/p-NF-κB p65 Pathway in the Development of Endometrial Stromal Cells in Pregnant Mice under Restraint Stress

Restraint stress causes various maternal diseases during pregnancy. β₂-Adrenergic receptor (β₂-AR) and Forkhead transcription factor class O 1 (FOXO1) are critical factors not only in stress, but also in reproduction. However, the role of FOXO1 in restraint stress, causing changes in the β₂-AR pathway in pregnant mice, has been unclear. The aim of this research was to investigate the β₂-AR pathway of restraint stress and its impact on the oxidative stress of the maternal uterus. In the study, maternal mice were treated with restraint stress by being restrained in a transparent and ventilated device before sacrifice on Pregnancy Day 5 (P5), Pregnancy Day 10 (P10), Pregnancy Day 15 (P15), and Pregnancy Day 20 (P20) as well as on Non-Pregnancy Day 5 (NP5). Restraint stress augmented blood corticosterone (CORT), norepinephrine (NE), and blood glucose levels, while oestradiol (E2) levels decreased. Moreover, restraint stress increased the mRNA levels of the FOXO family, β₂-AR, and even the protein levels of FOXO1 and β₂-AR in the uterus and ovaries. Furthermore, restraint stress increased uterine oxidative stress level. In vitro, the protein levels of FOXO1 were also obviously increased when β₂-AR was activated in endometrial stromal cells (ESCs). In addition, phosphorylated-nuclear factor kappa-B p65 (p-NF-κB p65) and its target genes decreased significantly when FOXO1 was inhibited. Overall, it can be said that the β₂-AR/FOXO1/p-NF-κB p65 pathway was activated when pregnant mice were under restraint stress. This study provides a scientific basis for the origin of psychological stress in pregnant women.

The Associations of Perceived and Oxidative Stress with Hypertension in a Cohort of Police Officers

PURPOSE

Associations between perceived stress and oxidative stress marker and metabolic syndrome (MetS) components were investigated in a cohort of police officers.

METHODS

Cross-sectional data from a cohort of non-diabetic subjects (n=233; 19F), median [interquartile range] age 50 [37-44] years, were analysed. MetS was construed in line with International Diabetes Federation (IDF) criteria and perceived stress with Cohen's 10-item Perceived Stress Scale. Plasma oxidative stress marker (free 8-iso-prostaglandin F_2α; 8-iso-PGF_2α), presence of coronary plaque, carotid artery intima-media thickness (cIMT), and physical activity level were also determined.

RESULTS

Obesity was established in 100 (42.92%), hypertension in 111 (47.64), whereas MetS was identified in 104 (44.63%) of the study subjects. A significant difference (p=0.003) in plasma 8-iso-PGF_2α level, depending on the MetS components status, was noted. The associations of perceived stress with plasma 8-iso-PGF_2α level and the select study variables were gender-specific. In multivariate analysis (adjusted for age and current smoking), positive associations of plasma 8-iso-PGF_2α levels with PSS score (B=0.108, 95% CI [0.008, 0.209], p=0.03) and systolic blood pressure (B=0.029, 95% CI [0.003, 0.057], p=0.02) in men only were established. Both the perceived stress (OR 1.101, 95% CI [1.001-1.202], p=0.03) and plasma 8-iso-PGF_2α levels (OR 1.223, 95% CI [1.046-1.432], p=0.01) impacted the prevalence of hypertension. Out of the MetS components, the effect of waist circumference (OR=1.138, 95% CI [1.064-1.218], p=0.0001) and glucose (B=2.696, 95% CI [1.081-6.725], p=0.03) were also encountered. No such associations were noted in women, though, neither in univariate nor in multivariate analyses. The prevalence of coronary plaque (0.001), obesity (p<0.001), hypertension (p<0.001) and median cIMT value (p=0.005), as well as leisure-time (p=0.04) and total walking physical activity (p=0.03), differed significantly between the subgroups stratified by MetS components status.

CONCLUSION

Both the perceived and oxidative stress were found instrumental in promoting hypertension in a cohort of police officers under study, whereas all study outcomes were conclusively gender-related.

RasGRF1 participates in the protective effect of tanshinone IIA on depressive like behaviors of a chronic unpredictable mild stress induced mouse model

Tanshinone IIA (Tan IIA) is reported to have neuroprotective effects to suppress cell apoptosis of cortical neurons induced by Aβ_25-35 through inhibiting oxidative stress. Nevertheless, few studies have investigated the effects of Tan IIA on depressive disorder. Here, we aimed to measure the effects of Tan IIA on chronic unpredictable mild stress (CUMS) induced mouse model and its underlying mechanism. For 28 days, mice were subjected to CUMS while Tan IIA was administered once daily at doses of 0, 1, 2.5, 5, or 10 mg/kg. CUMS exposure increased depressive-like behaviors, as indicated by increased immobility time in the forced swim and tail suspension tests, decreased sucrose preference in the sucrose preference test, and reduced exploratory behavior in the open field test. All of these behaviors were reversed dose-dependently by Tan IIA treatment. Oxidative stress was determined by measuring malondialdehyde, glutathione peroxidase, and superoxide dismutase activity and total antioxidant capacity. Levels of pro-inflammatory factors IL-1β and IL-18, cAMP response element binding protein and brain derived neurotrophic factor were detected by ELISA and western blot assay, respectively. The results showed that CUMS increased oxidative stress and pro-inflammatory factors and decreased levels of cAMP response element binding protein and brain-derived neurotrophic factor. Tan IIA treatment again reversed these effects. Importantly, RasGRF1 expression increased in CUMS-exposed mice but decreased after Tan IIA administration. Using RasGRF1^-/- mice to determine the role of RasGRF1 in mice exposed to CUMS, we found that knockdown of RasGRF1 reversed the effects of CUMS on mice, just like Tan IIA. These results indicate that Tan IIA may reverse depressive-like behaviors in CUMS-exposed mice by regulating RasGRF1.

Allium cepa Linn juice protect against alterations in reproductive functions induced by maternal dexamethsone treatment during lactation in male offspring of Wistar rats

Treatment with dams with dexamethasone during lactation has been reported to induce oxidative stress in the testis of the offspring. Allium cepa L (Red Onion) is known to be a potent free radical scavenger. The protective role of Allium cepa against oxidative stress induced in testis following treatment with dexamehasone during lactation in Wistar rats was assessed. Twenty female rats were assigned into four groups (n = 5) during lactation and they were treated as follows: Group 1 serve as Control (distilled water), Group 2, 3, and four were admistered dexamethasone (60 μg/kg), Allium cepa (5 ml/kg) and dexamethasone + Allium cepa respectively. Testicular descent, pubertal age, sperm quality indices, and serum hormonal profile were assessed as indices of reproductive function. Testicular malondialdehyde (MDA) reduced glutathione (GSH) as well as superoxide dismutase (SOD) and catalase activities were assessed as measures of oxidative stress. Results obtained showed that dexamethasone caused significant (P < 0.05) reduction in testes weights, indices of sperm quality, serum testosterone, FSH, LH levels and testicular antioxidant enzyme activities. There was significant delay (P < 0.05) in days of testes descent, preputial separation and increase in testicular MDA. However, maternal treatment with Allium cepa Linn juice significantly (P < 0.05) improved both indices of reproductive function and testicular antioxidant enzymes. These findings suggest that Allium cepa Linn has a protective effect against testicular oxidative stress and reproductive dysfunction following treatment of dams with dexamethasone during lactation.

Oxidation-reduction mechanisms in psychiatric disorders: A novel target for pharmacological intervention

While neurotransmitter dysfunction represents a key component in mental illnesses, there is now a wide agreement for a central pathophysiological hub that includes hormones, neuroinflammation, redox mechanisms as well as oxidative stress. With respect to oxidation-reduction (redox) mechanisms, preclinical and clinical evidence suggests that an imbalance in the pro/anti-oxidative homeostasis toward the increased production of substances with oxidizing potential may contribute to the etiology and manifestation of different psychiatric disorders. The substantial and continous demand for energy renders the brain highly susceptible to disturbances in its energy supply, especially following exposure to stressful events, which may lead to overproduction of reactive oxygen and nitrogen species under conditions of perturbed antioxidant defenses. This will eventually induce different molecular alterations, including extensive protein and lipid peroxidation, increased blood-brain barrier permeability and neuroinflammation, which may contribute to the changes in brain function and morphology observed in mental illnesses. This view may also reconcile different key concepts for psychiatric disorders, such as the neurodevelopmental origin of these diseases, as well as the vulnerability of selective cellular populations that are critical for specific functional abnormalities. The possibility to pharmacologically modulate the redox system is receiving increasing interest as a novel therapeutic strategy to counteract the detrimental effects of the unbalance in brain oxidative mechanisms. This review will describe the main mechanisms and mediators of the redox system and will examine the alterations of oxidative stress found in animal models of psychiatric disorders as well as in patients suffering from mental illnesses, such as schizophrenia and major depressive disorder. In addition, it will discuss studies that examined the effects of psychotropic drugs, including antipsychotics and antidepressants, on the oxidative balance as well as studies that investigated the effectiveness of a direct modulation of oxidative mechanisms in counteracting the behavioral and functional alterations associated with psychiatric disorders, which supports the promising role of the redox system as a novel therapeutic target for the improved treatment of brain disorders.

Potential roles of psychological and oxidative stress in insulin resistance: a cohort-based study

BACKGROUND

The present study investigated the relationships between psychological stress indices and oxidative stress marker, also when combined with emergent insulin resistance (IR), in the non-diabetic, middle-aged subjects, exposed to frequent/chronic psychological stressors.

METHODS

Cross-sectional data from a cohort of non-diabetic police officers (n = 234; 19F), aged 27-56 years, were used. Plasma inflammatory (CRP, TNF-α), oxidative stress (free 8-iso-prostaglandin F_2α; 8-iso-PGF_2α) markers, and insulin were measured. The value of homeostasis model assessment of IR index (HOMA-IR) was assumed the threshold value of IR, i.e. 2.04. Free cortisol in urine and perceived stress (psychological stress indices) were also measured.

RESULTS

In the IR subjects, most biochemical variables, inflammatory markers and urine cortisol were significantly higher, as compared to the non-IR ones. Psychological stress indices were associated with plasma 8-iso-PGF_2α [B = 0.139, 95% CI (0.048, 0.230), p = 0.002, and B = 0.007, 95% CI (0.0006, 0.014), p = 0.03; for perceived stress level and cortisol, respectively]. Positive associations were established between plasma 8-iso-PGF_2α [B = 0.069, 95% CI (0.016-0.120), p = 0.01] and urine cortisol [B = 0.003, 95% CI (0.0003, 0.005), p = 0.02] with HOMA-IR. Metabolic syndrome, as defined by IDF criteria, was established in 110 study subjects, whereas 136 of them were hypertensive. Waist circumference [B = 0.056, 95% CI (0.039, 0.074), p < 0.0001], and systolic blood pressure [B = 0.009, 95% CI (0.00003, 0.018), p = 0.04] were positively associated with HOMA-IR, whereas the association of HDL cholesterol [B = - 0.597, 95% CI (- 1.139, - 0.055), p = 0.03] was a negative one. Cortisol [OR = 1.007, 95% CI (1.002, 1.012), p = 0.006], and 8-iso-PGF_2α [OR = 1.103, 95% CI (1.010, 1.201), p = 0.02] affected the incidence of IR. After adjustment for metabolic syndrome (or its components), age, sex, and current smoking, the effects became non-significant. Out of metabolic syndrome components, waist circumference [OR 4.966, 95% CI (2.29, 10.751), p = 0.00004] and hypertriglyceridemia [OR 1.993, 95% CI (1.063, 3.736), p = 0.03] increased the chance of IR incidence.

CONCLUSIONS

Both psychological stress indices were associated with oxidative stress, but only cortisol with HOMA-IR. In the subjects exposed to frequent/chronic psychological stressors, cortisol and oxidative stress marker affected IR incidence, being statistically attenuated, though, following adjustment for metabolic syndrome, or its components.

Morphological and physiological consequences of a dietary restriction during early life in bats

Early life adverse conditions can have major consequences on an individual’s life history traits. Oxidative stress has been hypothesized to be one main mechanism underlying the negative consequences of early life adverse conditions. To test this hypothesis, we restricted the food availability of Seba’s short-tailed bat (Carollia perspicillata) mothers of unweaned pups for 10 days, followed by ad libitum provisioning. We also had a control, unrestricted group. We explored the morphological consequences of dietary restriction during early life by measuring growth rate. We also measured four markers of blood oxidative balance during growth. We assessed the level of cortisol, and its inactive form cortisone, in the hair of the pups at the end of growth. Finally, we monitored survival during the first year. Food restriction triggered a slowdown in growth followed by catch-up growth when ad libitum feeding was restored which did not lead to full compensation in size or mass compared to control individuals. We found that higher growth rate was associated with elevated oxidative damage, suggesting an oxidative cost to growth. However, we found no clear evidence for physiological costs specific to the catch-up growth. Survival after a year was not impacted by the treatment, the oxidative balance or the level of glucocorticoids at the end of growth. In conclusion, our results show that individuals were able to efficiently mitigate the short-term consequences of adverse early life conditions. However, consequences might arise in the long-term, and could impact reproductive success or lifespan.

More dynamic, more quantitative, unexpectedly intricate: Advanced understanding on synaptic RNA localization in learning and memory

Synaptic signaling exhibits great diversity, complexity, and plasticity which necessitates maintenance and rapid modification of a local proteome. One solution neurons actively exploit to meet such demands is the strategic deposition of mRNAs encoding proteins for both basal and experience-driven activities into ribonucleoprotein complexes at the synapse. Transcripts localized in this manner can be rapidly accessed for translation in response to a diverse range of stimuli in a temporal- and spatially-restricted manner. Here we review recent findings on localized RNAs and RNA binding proteins in the context of learning and memory, as revealed by cutting-edge in-vitro and in-vivo technologies capable of yielding quantitative and dynamic information. The new technologies include proteomic and transcriptomic analyses, high-resolution multiplexed RNA imaging, single-molecule RNA tracking in living neurons, animal models and human neuron cell models. Among many recent advances in the field, RNA chemical modification has emerged as one of the new regulatory layers of gene expression at synapse that is complex and yet largely unexplored. These exciting new discoveries have enhanced our understanding of the modulation mechanisms of synaptic gene expression and their roles in cognition.

Kleeb Bua Daeng, a Thai Traditional Herbal Formula, Ameliorated Unpredictable Chronic Mild Stress-Induced Cognitive Impairment in ICR Mice

Thai traditional herbal formula ''Kleeb Bua Daeng (KBD)''consists of a 1:1:1 ratio (dry weight) of three medicinal plants: Piper nigrum fruit, the aerial part of Centella asiatica and the petals of Nelumbo nucifera. Oral administration of KBD to unpredictable chronic mild stress (UCMS) mice significantly improved their cognitive function caused by chronic mild stress. Daily administration of KBD significantly decreased the serum corticosterone (CORT) and malondialdehyde (MDA) levels but increased the catalase and superoxide dismutase activities in both frontal cortex and hippocampus. The effects of KBD were similar to those caused by oral administration of vitamin E. HPLC analysis of the KBD extract revealed the presence of piperine, madecassoside, asiaticoside, luteolin-7-O-glucoside, rutin, kaempferol-3-glucoside, quercetin, kaempferol and ferulic acid as major constituents.

Antidepressant-like effect of a standardized hydroethanolic extract of Asparagus adscendens in mice

OBJECTIVE:

Asparagus adscendens Roxb. (Liliaceae), a traditional herbal medicine, has been used as an aphrodisiac and brain tonic in Asian countries. The aim of the present study is to investigate the antidepressant-like effect of standardized hydroethanolic extract of A. adscendens root and its possible mechanisms.

MATERIALS AND METHODS:

Mice administered with vehicle, imipramine (15 mg/kg/day; i.p.), and A. adscendens extract (AAE) (25, 50, and 100 mg/kg/day; i.p.) for 14 days were subjected to behavioral tests including forced swimming test (FST), tail suspension test (TST), and open-field test (OFT) on the 14^th day. In order to explore the underlying mechanism behind an antidepressant effect of AAE, the brain monoamine levels, oxidative stress parameters, and serum corticosterone levels were monitored.

RESULTS:

Our results indicated that pretreatment of AAE (25, 50, and 100 mg/kg) for 14 days statistically significantly (P < 0.01) demonstrated antidepressant-like effect as evidenced by reduced immobility time in both FST (105, 78.6, and 53.6 s) and TST (97.6, 73.5, and 54.67 s), with no significant change in spontaneous locomotor activities as observed in OFT. Further, the behavioral improvement was supported by the statistically significantly (P < 0.05) enhanced levels of monoamines and reduced corticosterone level along with amelioration of oxidative stress in AAE-treated animals as compared to vehicle control group.

Conclusion:

Our findings clearly demonstrated the antidepressant-like effect of AAE, which might have been mediated through the modulation of monoaminergic system and by regulating hypothalamic–pituitary–adrenal axis with amelioration of oxidative stress.

A Close Look at Echium amoenum Processing, Neuroactive Components, and Effects on Neuropsychiatric Disorders

Pharmacological researches in the area of herbal medicine have considerably increased over the last two centuries. Echium amoenum (known as Gol-e-Gavzaban in Persian) is a medicinal plant that has been widely used in Iranian folk medicine. In this review, databases including PubMed, Scopus, and Google Scholar were searched up. Data collecting was completed by January 2019 and available scientific reports regarding the processing methods, main chemical constituents, and effects of E. amoenum on different neuropsychiatric disorders are summarized. Thirteen five studies met the inclusion criteria. According to results, the important phytochemicals of the plant was phenolic compounds, fatty acids, rosmarinic acid, anthocyanidins, and flavonoids. Also, experimental and clinical studies demonstrated the effectiveness of E. amoenum in the treatment of several neuropsychiatric disorders such as anxiety, depression, ischemic stroke, seizure, Alzheimer's disease, and pain. Many of these effects are, at least in part, due to its rosmarinic acid or polyphenolic compounds such as flavonoids and natural pigments such as anthocyanins. Also, fatty acids such as gamma-linolenic acid play critical role in neuroactive properties of this herb. Among these effects, only the antidepressant and anxiolytic properties of the plant extract have been examined both experimentally and clinically. There was some controversy over its toxicity effects. It seems that E. amoenum protects neurons via attenuation of oxidative stress and inflammation as well as blocking of apoptosis in the nervous system. However, more studies are necessary for assessing exact mechanisms of action in neuropsychiatric disorders, finding of bioactive ingredients, and processing methods of this plant.

Anti-inflammatory and antioxidant effects of muscarinic acetylcholine receptor (mAChR) activation in the rat hippocampus

Recently we found that acute treatment with Oxotremorine (Oxo), a non-selective mAChRs agonist, up-regulates heat shock proteins and activates their transcription factor heat shock factor 1 in the rat hippocampus. Here we aimed to investigate: a) if acute treatment with Oxo may regulate pro-inflammatory or anti-inflammatory cytokines and oxidative stress in the rat hippocampus; b) if chronic restraint stress (CRS) induces inflammatory or oxidative alterations in the hippocampus and whether such alterations may be affected by chronic treatment with Oxo. In the acute experiment, rats were injected with single dose of Oxo (0.4 mg/kg) and sacrificed at 24 h, 48 h and 72 h. In the CRS experiment, the rats were exposed for 21 days to the CRS and then were treated with Oxo (0.2 mg/kg) for further 10 days. The acute Oxo treatment showed an ability to significantly reduce reactive oxygen species (ROS), singlet oxygen (¹O₂), pro-inflammatory cytokines levels (IL-1β and IL-6) and phosphorylated NF-κB-p65. Acute Oxo treatment also increased superoxide dismutase (SOD)-2 protein levels and stimulated SOD activity. No differences were detected in the anti-inflammatory cytokine levels, including IL-10 and TGF-β1. In the group of rats exposed to the CRS were found increased hippocampal IL-1β and IL-6 levels, together with a reduction of SOD activity level. These changes produced by CRS were counteracted by chronic Oxo treatment. In contrast, the upregulation of ROS and ¹O₂ levels in the CRS group was not counteracted by chronic Oxo treatment. The results revealed a hippocampal anti-inflammatory and antioxidant effect of Oxo treatment in both basal conditions and anti-inflammatory in the CRS rat model.

Allicin ameliorates obesity comorbid depressive-like behaviors: involvement of the oxidative stress, mitochondrial function, autophagy, insulin resistance and NOX/Nrf2 imbalance in mice

The increased prevalence of obesity has been a major medical and public health problem in the past decades. In obese status, insulin resistance and sustained oxidative stress damage might give rise to behavioral deficits. The anti-obesity and anti-oxidant effects of allicin have been previously reported in peripheral tissues. In the present study, the functions and mechanisms of allicin involved in the prevention of high-fat diet (HFD)-induced depressive-like behaviors were investigated to better understand the pharmacological activities of allicin. Obese mice (five weeks of age) were treated with allicin (50, 100, and 200 mg/kg) by gavage for 15 weeks and behavioral test (sucrose preference, open field, and tail suspension) were performed. Furthermore, markers of oxidative stress, mitochondrial function, autophagy, and insulin resistance were measured in the hippocampal tissue. Finally, the levels of NADPH oxidase (NOX2, NOX4) and the nuclear factor erythroid 2-related factor 2 (Nrf2) pathway were evaluated in the hippocampus. The body weight, metabolic disorders, and depressive-like behaviors in obese mice were ameliorated by allicin. The depressive-like behaviors presented in the obese mice were accompanied by remarkably excessive reactive oxygen species (ROS) production and oxidative stress, damaged mitochondrial function, imbalanced autophagy, and enhanced insulin resistance in the hippocampus. We found that allicin improved the above undesirable effects in the obese mice. Furthermore, allicin significantly decreased NOX2 and NOX4 levels and activated the Nrf2 pathway. Allicin attenuated depressive-like behaviors triggered by long-term HFD consumption by inhibiting ROS production and oxidative stress, improving mitochondrial function, regulating autophagy, and reducing insulin resistance in the hippocampus via optimization of NOX/Nrf2 imbalance.

A Discovery of Relevant Hepatoprotective Effects and Underlying Mechanisms of Dietary Clostridium butyricum Against Corticosterone-Induced Liver Injury in Pekin Ducks

Clostridium butyricum (C. butyricum) can attenuate oxidative stress, inflammation, and hepatic fatty deposition in poultry, however, the underlying mechanisms for this in Pekin ducks remain unclear. This study evaluated these hepatoprotective effects and the underlying mechanisms in a corticosterone (CORT)-induced liver injury model in Pekin ducks fed a C. butyricum intervention diet. A total of 500 Pekin ducks were randomly divided into five groups: one group (CON group) was only provided with a basal diet, three groups were provided a basal diet with 200 mg/kg (LCB group), 400 mg/kg (MCB group), or 600 mg/kg (HCB group) C. butyricum, respectively, and one group was provided a basal diet with 150 mg/kg aureomycin (ANT group) for 42 d. At 37 days-old, all ducks received daily intraperitoneal injections of CORT for five days to establish a liver injury model. C. butyricum intervention alleviated liver injury by decreasing the liver organ indices, hepatic steatosis and hepatocyte necrosis, and improving liver function, antioxidant capacity, and inflammatory factors. Hepatic RNA-seq revealed 365 differentially expressed genes (DEGs) between the MCB and CON groups, with 229 up- and 136 down-regulated DEGs in the MCB group. Between the MCB and ANT groups, 407 DEGs were identified, including 299 up- and 108 down-regulated genes in MCB group. Some DEGs in the MCB group related to oxidative stress and inflammatory responses such as Sod3, Tlr2a/b, and Il10, which were up-regulated, while Apoa1, Cyp7a1, Acsl1/5, Fasn, Ppar-γ, and Scd, which are involved in lipid metabolism, were down-regulated, indicating that these genes were responsive to dietary C. butyricum for the alleviation of corticosterone-induced hepatic injury. Toll-like receptor signaling, PI3K-Akt signaling pathway, cytokine-cytokine receptor interaction, peroxisome proliferator-activated receptor (PPAR) signaling pathway, adipocytokine and glycerophospholipid metabolism signaling pathway were significantly enriched in the MCB group. These findings indicate that C. butyricum intervention can protect Pekin ducks from corticosterone-induced liver injury by the modulation of immunoregulatory- and lipid metabolism-related genes and pathways.

Chronic restraint stress induces esophageal fibrosis with enhanced oxidative stress in a murine model

Although the underlying mechanism of stress remains unknown, it has been associated with the pathophysiology of gastroesophageal reflux diseases, the development of which appear to be accelerated by oxidative stress and fibrosis. The aim of the current study was to investigate the effect of chronic restraint stress on esophageal oxidative stress and fibrosis, as well as the impact of oxidative stress in a murine model whereby 8-week old C57BL/6J male mice were subjected to intermittent chronic restraint stress for a two-week period. The current study demonstrated that chronic restraint stress significantly reduced the body weight of mice compared with the control group. Although chronic restraint stress did not significantly alter the levels of triglycerides or cholesterol, free fatty acid concentration was significantly increased compared with the control group. Furthermore, chronic restraint stress significantly upregulated the expression levels of several fibrotic biomarkers including collagen type I, transforming growth factor β-1, α-smooth muscle actin and SMAD-3 compared with the control group. In addition, the expression levels of the reactive oxygen species (ROS) NADPH oxidase-4 and malondialdehyde were significantly increased, while the expression levels of nuclear factor erythroid 2-related factor 2 and heme oxygenase-1 were significantly decreased in esophageal tissue from mice in the chronic restraint stress group compared with the control group. In conclusion, chronic restraint stress may induce esophageal fibrosis by accumulating ROS and increasing fibrotic gene expression in a murine model.

Oxidative stress and mitochondrial responses to stress exposure suggest that king penguins are naturally equipped to resist stress

Exposure to unpredictable environmental stressors could influence animal health and fitness by inducing oxidative stress, potentially through downstream effects of glucocorticoid stress hormones (e.g. corticosterone) on mitochondrial function. Yet, it remains unclear whether species that have evolved in stochastic and challenging environments may present adaptations to alleviate the effects of stress exposure on oxidative stress. We tested this hypothesis in wild king penguins by investigating mitochondrial and oxidative stress responses to acute restraint-stress, and their relationships with baseline (potentially mirroring exposure to chronic stress) and stress-induced increase in corticosterone levels. Acute restraint-stress did not significantly influence mitochondrial function. However, acute restraint-stress led to a significant increase in endogenous antioxidant defences, while oxidative damage levels were mostly not affected or even decreased. High baseline corticosterone levels were associated with an up-regulation of the glutathione antioxidant system and a decrease in mitochondrial efficiency. Both processes might contribute to prevent oxidative damage, potentially explaining the negative relationship observed between baseline corticosterone and plasma oxidative damage to proteins. While stress exposure can represent an oxidative challenge for animals, protective mechanisms like up-regulating antioxidant defences and decreasing mitochondrial efficiency seem to occur in king penguins, allowing them to cope with their stochastic and challenging environment.

Oxidative stress and mitochondrial responses to stress exposure suggest that king penguins are naturally equipped to resist stress

Exposure to unpredictable environmental stressors could influence animal health and fitness by inducing oxidative stress, potentially through downstream effects of glucocorticoid stress hormones (e.g. corticosterone) on mitochondrial function. Yet, it remains unclear whether species that have evolved in stochastic and challenging environments may present adaptations to alleviate the effects of stress exposure on oxidative stress. We tested this hypothesis in wild king penguins by investigating mitochondrial and oxidative stress responses to acute restraint-stress, and their relationships with baseline (potentially mirroring exposure to chronic stress) and stress-induced increase in corticosterone levels. Acute restraint-stress did not significantly influence mitochondrial function. However, acute restraint-stress led to a significant increase in endogenous antioxidant defences, while oxidative damage levels were mostly not affected or even decreased. High baseline corticosterone levels were associated with an up-regulation of the glutathione antioxidant system and a decrease in mitochondrial efficiency. Both processes might contribute to prevent oxidative damage, potentially explaining the negative relationship observed between baseline corticosterone and plasma oxidative damage to proteins. While stress exposure can represent an oxidative challenge for animals, protective mechanisms like up-regulating antioxidant defences and decreasing mitochondrial efficiency seem to occur in king penguins, allowing them to cope with their stochastic and challenging environment.

The Behavioral Sequelae of Social Defeat Require Microglia and Are Driven by Oxidative Stress in Mice

Chronic social defeat (CSD) in male mice can produce anxiety and aberrant socialization. Animals susceptible to CSD show activation of microglia, which have elevated levels of oxidative stress markers. We hypothesized that microglia and reactive oxygen species (ROS) production contribute to the CSD stress-induced changes in affective behavior. First, we selectively depleted microglia (99%) by administering the CSF1R (colony-stimulating factor 1 receptor) antagonist PLX5622 before and during the 14 d CSD procedure. Microglia-depleted mice in contrast to nondepleted mice were protected from the stress effects measured by light/dark and social interaction tests. ROS production, measured histochemically following dihydroethidium administration, was elevated by CSD, and the production was reduced to basal levels in mice lacking microglia. The deleterious stress effects were also blocked in nondepleted mice by continuous intracerebral administration of N-acetylcysteine (NAC), a ROS inhibitor. In a second experiment, at the end of the CSD period, PLX5622 was discontinued to allow microglial repopulation. After 14 d, the brain had a full complement of newly generated microglia. At this time, the mice that had previously been protected now showed behavioral deficits, and their brain ROS production was elevated, both in all brain cells and in repopulated microglia. NAC administration during repopulation prevented the behavioral decline in the repopulated mice, and it supported behavioral recovery in nondepleted stressed mice. The data suggest that microglia drive elevated ROS production during and after stress exposure. This elevated ROS activity generates a central state supporting dysregulated affect, and it hinders the restoration of behavioral and neurochemical homeostasis after stress cessation.SIGNIFICANCE STATEMENT Chronic psychosocial stress is associated with psychiatric disorders such as depression and anxiety. Understanding the details of CNS cellular contributions to stress effects could lead to the development of intervention strategies. Inflammation and oxidative stress are positively linked to depression severity, but the cellular nature of these processes is not clear. The chronic social defeat (CSD) paradigm in mice produces mood alterations and microglial activation characterized by elevated reactive oxygen species (ROS) production. The depletion of microglia or ROS inhibition prevented adverse stress effects. Microglial repopulation of the brain post-CSD reintroduced adverse stress effects, and ROS inhibition in this phase protected against the effects. The results suggest that stress-induced microglial ROS production drives a central state that supports dysregulated affective behavior.