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1.
Prenatal infection is a major risk responsible for the occurrence of psychiatric conditions in infants. Mimicking maternal infection by exposing pregnant rodents to bacterial endotoxin lipopolysaccharide (LPS) also leads to major brain disorders in the offspring. The mechanisms of LPS action remain, however, unknown. Here, we show that LPS injection during pregnancy in rats, 2 days before delivery, triggered an oxidative stress in the hippocampus of male fetuses, evidenced by a rapid rise in protein carbonylation and by decreases in alpha-tocopherol levels and in the ratio of reduced/oxidized forms of glutathione (GSH/GSSG). Neither protein carbonylation increase nor decreases in alpha-tocopherol levels and GSH/GSSG ratio were observed in female fetuses. NMDA synaptic currents and long-term potentiation in CA1, as well as spatial recognition in the water maze, were also impaired in male but not in female 28-day-old offspring. Pretreatment with the antioxidant N-acetylcysteine prevented the LPS-induced changes in the biochemical markers of oxidative stress in male fetuses, and the delayed detrimental effects in male 28-day-old offspring, completely restoring both long-term potentiation in the hippocampus and spatial recognition performance. Oxidative stress in the hippocampus of male fetuses may thus participate in the neurodevelopmental damage induced by a prenatal LPS challenge.  相似文献   

2.
The plus-maze behavior was studied in offsprings of female rats subjected to immobilization stress on the 15-18 days of pregnancy. Prenatal stress decreased the level of anxiety in males and increased in females. The blockade of the mother's stress-induced glucocorticoid secretion by prior adrenalectomy and subsequent corticosterone injection during immobilization in a low dose (0.3 mg/kg) prevented the behavioral disorders in offsprings. In case of a higher dose of corticosterone (3 mg/kg) injection, the behavior of offsprings was the same as that of offsprings of the intact mothers subjected to immobilization. The results suggest that the stress-induced increase in maternal glucocorticoid level may be the mechanism by which prenatal stress impairs the development of sex differences in rat anxiety behavior.  相似文献   

3.
Antioxidant treatment has previously been shown to be neuroprotective in experimental bacterial meningitis. To obtain quantitative evidence for oxidative stress in this disease, we measured the major brain antioxidants ascorbate and reduced glutathione, and the lipid peroxidation endproduct malondialdehyde in the cortex of infant rats infected with Streptococcus pneumoniae. Cortical levels of the two antioxidants were markedly decreased 22 h after infection, when animals were severely ill. Total pyridine nucleotide levels in the cortex were unaltered, suggesting that the loss of the two antioxidants was not due to cell necrosis. Bacterial meningitis was accompanied by a moderate, significant increase in cortical malondialdehyde. While treatment with either of the antioxidants alpha-phenyl-tert-butyl nitrone or N-acetylcysteine significantly inhibited this increase, only the former attenuated the loss of endogenous antioxidants. Cerebrospinal fluid bacterial titer, nitrite and nitrate levels, and myeloperoxidase activity at 18 h after infection were unaffected by antioxidant treatment, suggesting that they acted by mechanisms other than modulation of inflammation. The results demonstrate that bacterial meningitis is accompanied by oxidative stress in the brain parenchyma. Furthermore, increased cortical lipid peroxidation does not appear to be the result of parenchymal oxidative stress, because it was prevented by NAC, which had no effect on the loss of brain antioxidants.  相似文献   

4.
Cai Q  Zhu Z  Li H  Fan X  Jia N  Bai Z  Song L  Li X  Liu J 《Life sciences》2007,80(7):681-689
Prenatal stress is known to cause neuronal loss and oxidative damage in the hippocampus of offspring rats. To further understand the mechanisms, the present study was undertaken to investigate the effects of prenatal stress on the kinetic properties of high-voltage-activated (HVA) Ca(2+) and K(+) channels in freshly isolated hippocampal CA3 pyramidal neurons of offspring rats. Pregnant rats in the prenatal stress group were exposed to restraint stress on days 14-20 of pregnancy three times daily for 45 min. The patch clamp technique was employed to record HVA Ca(2+) and K(+) channel currents. Prenatal stress significantly increased HVA Ca(2+) channel disturbance including the maximal average HVA calcium peak current amplitude (-576.52+/-7.03 pA in control group and -702.05+/-6.82 pA in prenatal stress group, p<0.01), the maximal average HVA Ca(2+) current density (-40.89+/-0.31 pA/pF in control group and -49.44+/-0.37 pA/pF in prenatal stress group, p<0.01), and the maximal average integral current of the HVA Ca(2+) channel (106.81+/-4.20 nA ms in control group and 133.49+/-4.59 nA ms in prenatal stress group, p<0.01). The current-voltage relationship and conductance--voltage relationship of HVA Ca(2+) channels and potassium channels in offspring CA3 neurons were not affected by prenatal stress. These data suggest that exposure of animals to stressful experience during pregnancy can exert effects on calcium ion channels of offspring hippocampal neurons and that the calcium channel disturbance may play a role in prenatal stress-induced neuronal loss and oxidative damage in offspring brain.  相似文献   

5.
Abstract: Glutamate-induced glutathione depletion in immature embryonic cortical neurons has been shown to lead to oxidative stress and cell death. We have used this in vitro model to investigate the mechanism(s) by which free radicals induce neuronal degeneration. We find that glutathione depletion leads to hypercondensation and fragmentation of chromatin into spherical or irregular shapes, a morphologic signature of apoptosis. These morphologic changes are accompanied by laddering of DNA into multiple oligonucleosomal fragments and can be prevented by the antioxidants idebenone and butylated hydroxyanisole. Cell death induced by glutathione depletion can also be prevented by inhibitors of macromolecular synthesis. Taken together, these observations suggest that oxidative stress can induce apoptosis in neurons.  相似文献   

6.
The effects of prenatal stress procedure were investigated in 3 months old male rats. Prenatally stressed rats showed depressive-like behavior in the forced swim test, including increased immobility, decreased mobility and decreased climbing. In ex vivo frontal cortex slices originating from prenatally stressed animals, the amplitude of extracellular field potentials (FPs) recorded in cortical layer II/III was larger, and the mean amplitude ratio of pharmacologically-isolated NMDA to the AMPA/kainate component of the field potential—smaller than in control preparations. Prenatal stress also resulted in a reduced magnitude of long-term potentiation (LTP). These effects were accompanied by an increase in the mean frequency, but not the mean amplitude, of spontaneous excitatory postsynaptic currents (sEPSCs) in layer II/III pyramidal neurons. These data demonstrate that stress during pregnancy may lead not only to behavioral disturbances, but also impairs the glutamatergic transmission and long-term synaptic plasticity in the frontal cortex of the adult offspring.  相似文献   

7.
Astaxanthin, a natural and nutritional red carotenoid pigment, is used as a dietary supplement. The intention of the present study was to investigate the beneficial effects of dietary pigment astaxanthin, against cyclophosphamide-induced oxidative stress and DNA damage. The end points of evaluation of the study included: (a) malondialdehyde, glutathione and superoxide dismutase concentration in liver to detect oxidative stress; (b) normal and modified alkaline comet assays (the latter includes lesion-specific enzymes formamidopyrimidine-DNA glycosylase and endonuclease-III) to detect normal and oxidative stress-induced DNA damage by cyclophosphamide in the mouse bone marrow and the peripheral blood lymphocytes. In addition, micronucleus assay and chromosomal aberration test capable of detecting the DNA damage were also carried out in peripheral blood and bone marrow of mice. Cyclophosphamide (100 mg/kg intra-peritoneal) treatment led to significant increase in liver malondialdehyde and decreased the antioxidant enzymes glutathione and superoxide dismutase. Further, cyclophosphamide also significantly increased the DNA damage as observed from normal and modified comet assays as well as micronucleus and chromosomal aberration assay. Pre-treatment with astaxanthin (12.5, 25 and 50 mg/kg/day for 5 days per oral) resulted in the restoration of oxidative stress markers such as malondialdehyde, glutathione and superoxide dismutase in liver. The amelioration of oxidative stress with astaxanthin pre-treatment correlated well with the decreased DNA damage as evident from normal and modified alkaline comet assays of bone marrow cells and peripheral blood lymphocytes. Further astaxanthin pre-treatment also reduced the frequency of chromosomal breakage and micronucleus formation in the mouse bone marrow cells and peripheral blood reticulocytes. It is thus concluded that pre-treatment with astaxanthin attenuates cyclophosphamide-induced oxidative stress and subsequent DNA damage in mice and it can be used as a chemoprotective agent against the toxicity of anticancer drug cyclophosphamide.  相似文献   

8.
We aimed to investigate the potential hazardous effects of prenatal and/or postnatal exposure to 1800 MHz GSM-like radiofrequency radiation (RFR) on the blood chemistry and lipid peroxidation levels of infant rabbits. A total of 72 New Zealand female and male white rabbits aged 1-month were used. Thirty-six female and 36 male were divided into four groups which were composed of nine infants: (i) Group 1 were the sham exposure (control), (ii) Group 2 were exposed to RFR, 15 min daily for 7 days in the prenatal period (between 15th and 22nd days of the gestational period) (prenatal exposure group). (iii) Group 3 were exposed to RFR 15 min/day (14 days for male, whereas 7 days for female) after they reached 1-month of age (postnatal exposure group). (iv) Group 4 were exposed to RFR for 15 min daily during 7 days in the prenatal period (between 15th and 22nd days of the gestational period) and 15 min/day (14 days for male, whereas 7 days for female) after they reached 1-month of age (prenatal and postnatal exposure group). Results showed that serum lipid peroxidation level in both female and male rabbits changed due to the RFR exposure. However, different parameters of the blood biochemistry were affected by exposure in male and female infants. Consequently, the whole-body 1800 MHz GSM-like RFR exposure may lead to oxidative stress and changes on some blood chemistry parameters. Studies on RFR exposure during prenatal and postnatal periods will help to establish international standards for the protection of pregnants and newborns from environmental RFR.  相似文献   

9.
Prenatal stress is associated with altered behavioral, cognitive, and psychiatric outcomes in offspring. Due to the importance of GABAergic systems in normal development and in psychiatric disorders, prenatal stress effects on these neurons have been investigated in animal models. Prenatal stress delays GABAergic progenitor migration, but the significance of these early developmental disruptions for the continued development of GABAergic cells in the juvenile brain is unclear. Here, we examined effects of prenatal stress on populations of GABAergic neurons in juvenile and adult medial frontal cortex (mFC) and hippocampus through stereological counting, gene expression, and relevant anxiety‐like and social behaviors. Postnatally, the total GABAergic cell number that peaks in adolescence showed altered trajectories in mFC and hippocampus. Parvalbumin neuron proportion in juvenile brain was altered by prenatal stress, but parvalbumin gene expression showed no differences. In adult brain, parvalbumin neuron proportions were altered by prenatal stress with opposite gene expression changes. Adult prenatally stressed offspring showed a lack of social preference on a three‐chambered task, increased anxiety‐like behavior on the elevated plus maze, and reduced center time in an open field. Despite a lack of significant group differences in adult total GABAergic cell populations, performance of these tasks was correlated with GABAergic populations in mFC and hippocampus. In conclusion, prenatal stress resulted in a delay in GABAergic cell number and maturation of the parvalbumin subtype. Influences of prenatal stress on GABAergic populations during developmentally dynamic periods and during adulthood may be relevant to the anxiety‐like behaviors that occur after prenatal stress. © 2015 Wiley Periodicals, Inc. Develop Neurobiol 76: 1078–1091, 2016  相似文献   

10.
Antioxidants have possible therapeutic value in neurodegenerative disorders, although they may have pro-oxidant effects under certain conditions. Glutathione (GSH) is a key free radical scavenger. N-acetylcysteine (NAC) bolsters GSH and intracellular cysteine and also has effective free radical scavenger properties. The effects of chronic NAC administration (50 mg/kg/day, 500 mg/kg/day, 1500 mg/kg/day × 21 days) on cellular markers of oxidative status was studied in striatum of healthy male Sprague-Dawley rats as well as in animals with apparent striatal oxidative stress following chronic haloperidol treatment (1.5 mg/kg/day × 3 weeks). In non-haloperidol treated animals, NAC 50 and 500 mg/kg did not affect oxidative status, although NAC 1,500 mg/kg significantly increased striatal superoxide levels, decreased lipid peroxidation and increased consumption of reduced glutathione (GSH). Haloperidol alone evoked a significant increase in superoxide and lipid peroxidation. All NAC doses blocked haloperidol induced increases in superoxide levels, while NAC 500 mg/kg and 1,500 mg/kg prevented haloperidol-associated lipid peroxidation levels and also increased the GSSG/GSH ratio. NAC may protect against conditions of striatal oxidative stress, although possible pro-oxidative actions at high doses in otherwise healthy individuals, e.g. to offset worsening of neurodegenerative illness, should be viewed with caution.  相似文献   

11.
Previously we demonstrated that insulin protects against neuronal oxidative stress by restoring antioxidants and energy metabolism. In this study, we analysed how insulin influences insulin-(IR) and insulin growth factor-1 receptor (IGF-1R) intracellular signaling pathways after oxidative stress caused by ascorbate/Fe2+ in rat cortical neurons. Insulin prevented oxidative stress-induced decrease in tyrosine phosphorylation of IR and IGF-1R and Akt inactivation. Insulin also decreased the active form of glycogen synthase kinase-3beta (GSK-3beta) upon oxidation. Since phosphatidylinositol 3-kinase (PI-3K)/Akt-mediated inhibition of GSK-3beta may stimulate protein synthesis and decrease apoptosis, we analysed mRNA and protein expression of "candidate" proteins involved in antioxidant defense, glucose metabolism and apoptosis. Insulin prevented oxidative stress-induced increase in glutathione peroxidase-1 and decrease in hexokinase-II expression, supporting previous findings of changes in glutathione redox cycle and glycolysis. Moreover, insulin precluded Bcl-2 decrease and caspase-3 increased expression. Concordantly, insulin abolished caspase-3 activity and DNA fragmentation caused by oxidative stress. Thus, insulin-mediated activation of IR/IGF-1R stimulates PI-3K/Akt and inhibits GSK-3beta signaling pathways, modifying neuronal antioxidant defense-, glucose metabolism- and anti-apoptotic-associated protein synthesis. These and previous data implicate insulin as a promising neuroprotective agent against oxidative stress associated with neurodegenerative diseases.  相似文献   

12.
13.
Stress can be defined as physical and psychological modifications that disrupt the homeostasis and the balance of organisms. Stress is known as one of the most important reasons of several diseases. In the present study, the anti-stress effect of betaine was evaluated with reference to its antioxidant property. Wistar albino rats were divided into four groups such as control, betaine, restraint stress (6 h/day for 30 days), and betaine + restraint stress. The oxidative damage was assessed by measuring the protein and corticosterone in plasma, lipid peroxidation, non-enzymic (reduced glutathione), and enzymic antioxidants (glutathione peroxidase, glutathione-S-transferase, catalase, and superoxide dismutase) in the lymphoid organs of thymus and spleen. Followed by the induction of restraint stress, the non-enzymic and enzymic antioxidants were significantly decreased with concomitant increase observed in the levels of corticosterone and lipid peroxidation. Oral pretreatment with betaine (250 mg/kg body weight daily for a period of 30 days) significantly (P < 0.001) prevented the restraint stress-induced alterations in the levels of protein and corticosterone in plasma of experimental groups of rats. It counteracted the restraint stress-induced lipid peroxidation and maintained the antioxidant defense system in the lymphoid tissues at near normal. The findings suggest that betaine possesses significant anti-stress activity, which may be due to its antioxidant property.  相似文献   

14.
Maternal intake of flavonoids, known for their antioxidant properties, may affect the offspring's susceptibility to developing chronic diseases at adult age, especially those related to oxidative stress, via developmental programming. Therefore, we supplemented female mice with the flavonoids genistein and quercetin during gestation, to study their effect on the antioxidant capacity of lung and liver of adult offspring. Maternal intake of quercetin increased the expression of Nrf2 and Sod2 in fetal liver at gestational day 14.5. At adult age, in utero exposure to both flavonoids resulted in the increased expression of several enzymatic antioxidant genes, which was more pronounced in the liver than in the adult lung. Moreover, prenatal genistein exposure induced the nonenzymatic antioxidant capacity in the adult lung, partly by increasing glutathione levels. Prenatal exposure to both flavonoids resulted in significantly lower levels of oxidative stress-induced DNA damage in liver only. Our observations lead to the hypothesis that a preemptive trigger of the antioxidant defense system in utero had a persistent effect on antioxidant capacity and as a result decreased oxidative stress-induced DNA damage in the liver.  相似文献   

15.
Chronic oxidative stress plays an important role in depression. The aim of present study was to examine the stress-induced changes in serum corticosterone (CORT) levels, cytosolic protein carbonyl groups, malondialdehyde (MDA), reduced glutathione (GSH), nitric oxide (NO) and total superoxide dismutase (SOD) activity in the prefrontal cortex versus hippocampus of male Wistar rats exposed to acute (2 h of immobilization or cold), chronic (21d of social isolation) stress, and their combination (chronic + acute stress). The subcellular distribution of nuclear factor-κB (NF-κB) and cytosolic cyclooxygenase 2 (COX-2) protein expressions were also examined. Depressive- and anxiety-like behaviors were assessed via the forced swim, sucrose preference, and marble burying tests in chronically isolated rats. Although both acute stressors resulted in elevated CORT, increased MDA in the prefrontal cortex and NF-κB activation accompanied by increased NO in the hippocampus were detected only following acute cold stress. Chronic isolation resulted in no change in CORT levels, but disabled appropriate response to novel acute stress and led to depressive- and anxiety-like behaviors. Increased oxidative/nitrosative stress markers, likely by NF-κB nuclear translocation and concomitant COX-2 upregulation, associated with decreased SOD activity and GSH levels, suggested the existence of oxidative stress in the prefrontal cortex. In contrast, hippocampus was less susceptible to oxidative damage showing only increase in protein carbonyl groups and depleted GSH. Taken together, the prefrontal cortex seems to be more sensitive to oxidative stress than the hippocampus following chronic isolation stress, which may be relevant for further research related to stress-induced depressive-like behavior.  相似文献   

16.
The effects of prenatal stress on the hypothalamic-pituitary-adrenal (HPA) axis activity and brain glycocorticoid receptors were studied in neonatal male and female offspring, as well as the influence of neonatal glycocorticoid receptors blockade on hormonal stress reactivity of adult rats. The results showed that there were sexual differences in plasma corticosterone level and corticosteroid binding in the cortex and hypothalamus of 5-day old control rats. Prenatal stress increased basal level of corticosterone in female rats, decreased corticosterone binding in hypothalamus and hippocampus of male and female rats, and increased corticosteroid receptor level in the male cortex. Neonatal administration of glycocorticoid receptor antagonist did not change plasma corticosterone level in 5-day old rats, but prolonged hormonal stress response of the HPA axis in adult male rats and increased hormonal stress response in female ones. The character of the IIPA axis activity of male and female rats with neonatal blockade of glycocorticoid receptors correspond to hormonal stress response of prenatal stressed rats. These data suggest that change of brain glycocorticoid receptors function in neonatal period of development might be one of the mechanisms of prenatal stress influence on the HPA axis activity in the adulthood.  相似文献   

17.
Maternal stress can disturb normal fetal neurodevelopmental progress, and lead to negative behavioral and neuroendocrine consequences for the offspring. These effects may be related to alterations in the hypothalamic–pituitary–adrenal (HPA) axis. Early life events disrupting the function of the HPA axis may be associated with epigenetic modification. This study investigated the effect of maternal stress on the methylation rate of the corticotrophin-releasing hormone (CRH) promoter and HPA axis response to acute stress in the adolescent offspring of Sprague–Dawley rats. Pregnant dams were randomly assigned to two groups: restraint stress group and normal control group. Adolescent male and female offspring were used from each group. The results showed that prenatal stress is associated with the demethylation of the CRH promoter, and leads to anxiety-like behaviors in adolescent life stages, as well as hyper-responsiveness of the HPA axis. Together, these results imply that prenatal stress alters the normal HPA function, which may be via the epigenetic mechanism.  相似文献   

18.
Impairment of neuroendocrine, immune and antioxidant defenses contribute to pathophysiology of stress-induced depression. Somatostatin executes diverse regulatory effects on endocrine, exocrine and neural functions; however, the possibility that octreotide, a synthetic somatostatin analogue might mitigate stress-induced depression remains elusive. Hence, the current study aimed to explore the immunomodulatory and antioxidant effects of octreotide in a model of chronic mild stress (CMS). This paradigm was performed by exposing rats to a combination of mild unpredictable stressors for 21 days. Fifty male Wistar rats were divided into five groups; (1) control receiving saline, (2) octreotide given to normal unstressed animals. The remaining three groups were subjected to (3) CMS alone or in combination with octreotide (4) 50 μg/kg or (5) 90 μg/kg. Octreotide increased sucrose preference index and attenuated CMS-induced increases in plasma adrenocorticotrophic hormone and corticosterone levels. In addition, octreotide decreased plasma tumor necrosis factor-alpha concentration. Moreover, it prevented CMS-induced oxidative damage by enhancing the antioxidant defenses superoxide dismutase, glutathione reductase and glutathione in the hippocampus. Furthermore, octreotide normalized the elevated malondialdehyde and lactate dehydrogenase levels in the hippocampus. These results demonstrate a possible antidepressant-like activity of octreotide in CMS due to its antioxidant/antiinflammatory aptitude.  相似文献   

19.
Results of the very first experiments conducted to evaluate therapeutic potentials of a fumarate containing Fumaria indica extract and of fairly low daily oral doses of monomethyl fumarate for prevention of chronic unavoidable foot-shock stress-induced gastric ulcers, and possible involvement of diverse neuro-hormonal and oxidative process in their stress response desensitizing effects are reported and discussed in this article. Preventive effects of 21 daily oral 60, 120, and 240 mg/kg doses of a standardized 50 % methanolic F. indica extract (MFI) and 1.25, 2.50, and 5.00 mg/kg/day of pure monomethyl fumarate (MMF) were compared in rats subjected to one hour daily unavoidable foot-shocks. A pharmaceutically well-standardized Withania somnifera (WS) root extract was used as a reference herbal anti-stress agent in all experiments. Effects of the treatments on stress-induced alterations in body weight, adrenal and spleen weights, gastric ulcer and ulcer index, weight of glandular stomach, protective mucosal glycoprotein content, cellular proliferation, oxidative stress on stomach fundus, and brain tissues of male rats were quantified. Other parameters quantified were plasma corticosterone levels, brain monoamine levels, and expressions of the cytokines TNF-α, IL-10, and IL-1β in blood and brain of stressed and treated rats. Most but not every observed stress-induced anomalies were suppressed or completely prevented by both MFI and pure MMF treatments in dose-dependent manner. Qualitatively, the observed activity profiles of both of them were similar to those of WS dose tested. These results reveal that both MFI and MMF are potent gastro-protective agents against chronic unavoidable stress-induced ulcers and strongly suggest that they act as regulators or modulators of monoamine, corticosterone, and cytokine homeostasis.  相似文献   

20.
Effects of dams stress on the carboxypeptidase H: the neuropeptide exchange enzyme in the hypothalamo-pituitary-adrenall-gonadal system, was studied in the litter of different age (0, 14, 28, 45, and 120 day after birth) was studied. The sex differences in dynamic of enzyme activity in intact animals are substantiated. The effect of prenatal stress on carboxypeptidase H activity dependes on age and sex of animals. Prenatal stress is altering during the age dynamics of enzyme activity. This in the pituitary gland and hypothalamus of prenatal stressed female rats was a control for the male rats. In the adrenal and gonadal gland of prenatal stressed males, this was a control for the female rats female. The role of carboxypeptidase H in pubescence and mechanisms of effect of prenatal stress on sex system functional are discussed.  相似文献   

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