NADPH oxidase and redox status in amygdala, hippocampus and cortex of male Wistar rats in an animal model of post-traumatic stress disorder.

Post-traumatic stress disorder (PTSD) is a highly prevalent and impairing disorder. Oxidative stress is implicated in its pathogenesis. Nicotinamide adenine dinucleotide phosphate (NADPH) oxidase is an important source of free radicals. The aim of the study was to assess oxidative stress parameters, activities of respiratory chain enzymes, and the expression of NADPH oxidase subunits (gp91phox, p22phox, and p67phox) in the single prolonged stress (SPS) animal model of PTSD. Twenty-four (12 controls; 12 subjected to SPS), 9-week-old, male Wistar rats were used. SPS included physical restraint, forced swimming, and ether exposure. The rats were euthanized seven days later. Cortex, hippocampus, amygdala, and thalamus were dissected. Malondialdehyde (MDA), reduced glutathione (GSH), superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT), Complex I, and cytochrome C oxidase were measured using spectrophotometric methods, while the expression of NADPH oxidase subunits was determined by Western blot. Increased MDA and decreased GSH concentrations were found in the amygdala and hippocampus of the SPS rats. SOD activity was decreased in amygdala and GPx was decreased in hippocampus. Increased expression of the NADPH oxidase subunits was seen in amygdala, while mitochondrial respiratory chain enzyme expression was unchanged both in amygdala and hippocampus. In the cortex concentrations of MDA and GSH were unchanged despite increased Complex I and decreased GPx, while in the thalamus no change of any parameter was noticed. We conclude that oxidative stress is present in hippocampus and amygdala seven days after the SPS procedure. NADPH oxidase seems to be a main source of free radicals in the amygdala.

Effects of IL-33/ST2 pathway in acute inflammation on tissue damage, antioxidative parameters, magnesium concentration and cytokines profile.

AIM: The aim of this study was to examine the role of IL-33/ST2 pathway in a pathogenesis of acute inflammation and its effects on tissue damage, antioxidative capacity, magnesium concentration and cytokine profile in acutely inflamed tissue. MATERIAL AND METHODS: Male mice were randomly divided in four groups: wild-type control group (WT-C), ST2 knockout control group (KO-C), wild-type inflammatory group (WT-I), and ST2 knockout inflammatory group (KO-I). Acute inflammation was induced in WT-I and KO-I by intramuscular injection of turpentine oil, while mice in WT-C and KO-C were treated with saline. After 12h, animals were euthanized, and blood was collected for determination of creatine kinase (CK) and aspartate transaminase (AST) activity. The treated tissue was used for histopathological analysis, determination of volume density of inflammatory infiltrate (Vdii) and necrotic fiber (Vdnf), gene expression of interleukin (IL)-33, ST2, tumor necrosis factor alpha (TNF-alpha), IL-6, IL-12p35, and transforming growth factor beta (TGF-beta), concentration of magnesium (Mg), copper (Cu), selenium (Se), manganese (Mn) and reduced glutathione (GSH), and superoxide dismutase (SOD) and glutathione peroxidase (GPx) activity. RESULTS: Presence of inflammatory infiltration and necrosis in the treated tissue was histopathologically confirmed in WT-I and KO-I. Vdii was significantly higher in WT-I when compared to KO-I, whereas Vdnf did not significantly differ between WT-I and KO-I. CK and AST significantly increased in both inflammatory groups when compared to corresponding control groups. However, the values of CK and AST were significantly higher in WT-I than in KO-I. Mg in the treated tissue was significantly lower in WT-I in comparison to WT-C and KO-I, while there was no significant difference between KO-C and KO-I. There was no significant difference in Cu, Se, and Mn in the treated tissue between WT-C, KO-C, WT-I and KO-I. Gene expression of IL-33 in the treated tissue increased in both inflammatory groups when compared to the corresponding control groups, but it was significantly higher in KO-I than in WT-I. Gene expression of ST2 in the treated tissue was significantly higher in WT-I than in WT-C. Gene expression of TNF-alpha, IL-6, and IL-12p35 in the treated tissue was significantly higher in WT-I and KO-I than in the corresponding control groups, and IL-6 was significantly higher in KO-C than in WT-C. TGF-beta gene expression in the treated tissue was significantly higher in KO-I when compared to WT-I, while there was no difference between WT-C and KO-C. SOD activity decreased at the site of acute inflammation in both inflammatory groups, while the GPx activity increased. GSH in the treated tissue was significantly higher in KO-I than in KO-C or WT-I. CONCLUSION: The results of our study have indicated, to our knowledge for the first time, that IL-33/ST2 pathway plays a role in enhancing inflammation and tissue damage at the site of acute inflammation by affecting the concentration of magnesium and GSH, important for antioxidative capacity, as well as gene expression of anti-inflammatory cytokine TGF-beta.

Anxiety-related behavior in hyperhomocysteinemia induced by methionine nutritional overload in rats: role of the brain oxidative stress.

The aim of this study was to examine the effects of a methionine-enriched diet on anxiety-related behavior in rats and to determine the role of the brain oxidative status in these alterations. Adult male Wistar rats were fed from the 30th to 60th postnatal day with standard or methionine-enriched diet (double content comparing with standard diet: 7.7 g/kg). Rats were tested in open field and light-dark tests and afterwards oxidative status in the different brain regions were determined. Hyperhomocysteinemia induced by methionine-enriched diet in this study decreased the number of rearings, as well as the time that these animals spent in the center of the open field, but increased index of thigmotaxy. Oxidative status was selectively altered in the examined regions. Lipid peroxidation was significantly increased in the cortex and nc. caudatus of rats developing hyperhomocysteinemia, but unaltered in the hippocampus and thalamus. Based on the results of this research, it could be concluded that hyperhomocysteinemia induced by methionine nutritional overload increased anxiety-related behavior in rats. These proanxiogenic effects could be, at least in part, a consequence of oxidative stress in the rat brain.

Long-term Effects of Maternal Deprivation on the Volume, Number and Size of Neurons in the Amygdala and Nucleus Accumbens of Rats.

BACKGROUND: Maternal deprivation (MD) in rodents is an important neurodevelopmental model for studying a variety of behavioral changes which closely resemble the symptoms of schizophrenia in humans. SUBJECTS AND METHODS: To determine whether early-life stress leads to changes in the limbic system structures: the amygdala and the nucleus accumbens, 9-day-old Wistar rats were exposed to 24 hour MD. On P60 the rats were sacrificed for morphometric analysis and their brains were compared to the control group. RESULTS: Results show that MD affected important limbic system structures: the amygdala and the nucleus accumbens, whose volume was decreased (17% of the control value for the amygdala and 9% of the control value for the nucleus accumbens ), as well as the number of neurons (41% of the control value for the amygdala and 43% of the control value for the nucleus accumbens ) and the size of their cells soma (12% of the control value for the amygdala and 33% of the control value for the nucleus accumbens ). CONCLUSION: This study indicates that early stress in life leads to changes in the morphology of the limbic areas of the brain, most probably due to the loss of neurons during postnatal development, and it further contributes to our understanding of the effects of maternal deprivation on brain development.

The influence of sex hormones on anterior cruciate ligament ruptures in males.

PURPOSE: The purpose of this study is to determine the difference in the concentrations of testosterone, 17-ß estradiol and progesterone between male patients with and without ACL rupture, as well as the possible effect of these hormones on generalized joint laxity. METHODS: Male subjects with non-contact knee joint injury were included in this study. Two groups were formed: the examined group, consisting of subjects with ACL rupture and the control group consisting of patients without ACL rupture. After this, the patients from these two groups were paired off on the basis of three factors, level of professional involvement in sports (including the type of sports activity), left or right side of the body and the age of the subjects. In the end, there were 29 pairs (58 subjects). The concentration of sex hormones was determined from saliva specimens with the aid of the Salimetrics enzyme immunoassay. The testing of generalized joint laxity was performed with the aid of the "laxity score" according to Beighton et al. RESULTS: Subjects with ACL rupture have highly statistically significantly greater concentrations of testosterone (p < 0.01), statistically significantly greater concentrations of 17-ß estradiol (p < 0.05), and a highly statistically significantly greater generalized joint laxity score than subjects with an intact ACL (p < 0.01). CONCLUSION: Increased concentrations of testosterone or 17-ß estradiol may be a risk factor leading to ACL rupture. Also, generalized joint laxity may be a factor leading to ACL rupture, but none of the monitored hormones can be set down as the cause of its existence. Young male athletes with higher concentrations of testosterone and greater hyperelasticity should plan preventive programs of physiotherapy for ACL preservation since they present a vulnerable group susceptible to ACL rupture. LEVEL OF EVIDENCE: Diagnostic study, Level II.

The influence of sex hormones on anterior cruciate ligament rupture: female study.

PURPOSE: The purpose of this study was to determine the difference in the concentrations of testosterone, 17-ß estradiol and progesterone between female patients with and without ACL rupture and the possible effect of these hormones on generalised joint laxity. METHODS: Female subjects with non-contact knee joint injury were included in this study. They were divided into two groups: the examined group, consisting of female subjects with ACL rupture, and the control group, consisting of female patients without ACL rupture. In the next step, the patients from these two groups were paired off on the basis of three factors: the level of professional sports involvement (including the type of sports activity), the side of the body where the injury had occurred (left or right) and the age of the subjects. In the end, there were 12 pairs (24 subjects). The concentrations of sex hormones were established from saliva specimens with the aid of the Salimetrics enzyme immunoassay. Generalised joint laxity was tested with the aid of the "laxity score" according to Beighton, Solomon and Soskolne. RESULTS: Female subjects with ACL rupture had significantly lower concentrations of testosterone (p < 0.01), significantly lower concentrations of 17-ß estradiol (p < 0.05) and significantly lower concentrations of progesterone (p < 0.01) than female subjects with intact ACL. CONCLUSIONS: Decreased concentrations of testosterone, 17-ß estradiol or progesterone may be a risk factor leading to ACL rupture. The concentrations of these hormones do not affect generalised joint laxity. Additional research on a larger group of patients is necessary to further determine the effects of these hormones on generalised joint laxity and ACL ruptures. Young female athletes with lower concentrations of sex hormones are more prone to anterior cruciate ligament rupture which is why they need to reduce their sports activities during the pre-ovulatory phase of the menstrual cycle, when these concentrations are additionally reduced.

Finasteride improves motor, EEG, and cellular changes in rat brain in thioacetamide-induced hepatic encephalopathy.

Neurosteroids are involved in the pathogenesis of hepatic encephalopathy (HE). This study evaluated the effects of finasteride, inhibitor of neurosteroid synthesis, on motor, EEG, and cellular changes in rat brain in thioacetamide-induced HE. Male Wistar rats were divided into the following groups: 1) control; 2) thioacetamide-treated group, TAA (300 mg·kg(-1)·day(-1)); 3) finasteride-treated group, FIN (50 mg·kg(-1)·day(-1)); and 4) group treated with FIN and TAA (FIN + TAA). Daily doses of TAA and FIN were administered in three subsequent days intraperitoneally, and in the FIN + TAA group FIN was administered 2 h before every dose of TAA. Motor and reflex activity was determined at 0, 2, 4, 6, and 24 h, whereas EEG activity was registered about 24 h after treatment. The expressions of neuronal (NeuN), astrocytic [glial fibrilary acidic protein (GFAP)], microglial (Iba1), and oligodendrocyte (myelin oligodendrocyte glycoprotein) marker were determined 24 h after treatment. While TAA decreased all tests, FIN pretreatment (FIN + TAA) significantly improved equilibrium, placement test, auditory startle, head shake reflex, motor activity, and exploratory behavior vs. the TAA group. Vital reflexes (withdrawal, grasping, righting and corneal reflex) together with mean EEG voltage were significantly higher (P < 0.01) in the FIN + TAA vs. the TAA group. Hippocampal NeuN expression was significantly lower in TAA vs. control (P < 0.05). Cortical Iba1 expression was significantly higher in experimental groups vs. control (P < 0.05), whereas hippocampal GFAP expression was increased in TAA and decreased in the FIN + TAA group vs. control (P < 0.05). Finasteride improves motor and EEG changes in TAA-induced HE and completely prevents the development of hepatic coma.

Hyperhomocysteinemia induced by methionine dietary nutritional overload modulates acetylcholinesterase activity in the rat brain.

Methionine is the only endogenous precursor of homocysteine, sulfur-containing amino acid and well known as risk factor for various brain disorders. Acetylcholinesterase is a serine protease that rapidly hydrolyzes neurotransmitter acetylcholine. It is widely distributed in different brain regions. The aim of this study was to elucidate the effects of methionine nutritional overload on acetylcholinesterase activity in the rat brain. Males of Wistar rats were randomly divided into control and experimental group, fed from 30th to 60th postnatal day with standard or methionine-enriched diet (double content comparing to standard, 7.7 g/kg), respectively. On the 61st postnatal day, total homocysteine concentration was determined and showed that animals fed with methionine-enriched diet had significantly higher serum total homocysteine concentrations comparing to control rats (p < 0.01). Acetylcholinesterase activity has been determined spectrophotometrically in homogenates of the cerebral cortex, hippocampus, thalamus, and nc. caudatus. Acetylcholinesterase activity showed tendency to decrease in all examined brain structures in experimental comparing to control rats, while statistical significance of this reduction was achieved in the cerebral cortex (p < 0.05). Brain slices were stained with haematoxylin and eosin (H&E) and observed under light microscopy. Histological analysis of H&E-stained brain slices showed that there were no changes in the brain tissue of rats which were on methionine-enriched diet compared to control rats. Results of this study showed selective vulnerability of different brain regions on reduction of acetylcholinesterase activity induced by methionine-enriched diet and consecutive hyperhomocysteinemia.

Protective effects of glucose-6-phosphate dehydrogenase on neurotoxicity of aluminium applied into the CA1 sector of rat hippocampus.

BACKGROUND & OBJECTIVES: Aluminum (Al) toxicity is closely linked to the pathogenesis of Alzheimer's disease (AD). This experimental study was aimed to investigate the active avoidance behaviour of rats after intrahippocampal injection of Al, and biochemical and immunohistochemical changes in three bilateral brain structures namely, forebrain cortex (FBCx), hippocampus and basal forebrain (BF). METHODS: Seven days after intra-hippocampal (CA1 sector) injection of AlCl3 into adult male Wistar rats they were subjected to two-way active avoidance (AA) tests over five consecutive days. Control rats were treated with 0.9% w/v saline. The animals were decapitated on the day 12 post-injection. The activities of acetylcholinesterase (AChE) and glucose-6-phosphate dehydrogenase (G6PDH) were measured in the FBCx, hippocampus and BF. Immunohistochemical staining was performed for transferrin receptors, amyloid ß and tau protein. RESULTS: The activities of both AChE and G6PDH were found to be decreased bilaterally in the FBCx, hippocampus and basal forebrain compared to those of control rats. The number of correct AA responses was reduced by AlCl3 treatment. G6PDH administered prior to AlCl 3 resulted in a reversal of the effects of AlCl3 on both biochemical and behavioural parameters. Strong immunohistochemical staining of transferrin receptors was found bilaterally in the FBCx and the hippocampus in all three study groups. In addition, very strong amyloid ß staining was detected bilaterally in all structures in AlCl3-treated rats but was moderate in G6PDH/AlCl3-treated rats. Strong tau staining was noted bilaterally in AlCl3-treated rats. In contrast, tau staining was only moderate in G6PDH/AlCl3-treated rats. INTERPRETATION & CONCLUSIONS: Our findings indicated that the G6PDH alleviated the signs of behavioural and biochemical effects of AlCl3-treatment suggesting its involvement in the pathogenesis of Al neurotoxicity and its potential therapeutic benefit. The present model could serve as a useful tool in AD investigations.

Influence of the green tea leaf extract on neurotoxicity of aluminium chloride in rats.

Aluminium may have an important role in the aetiology/pathogenesis/precipitation of Alzheimer's disease. Because green tea (Camellia sinensis L.) reportedly has health-promoting effects in the central nervous system, we evaluated the effects of green tea leaf extract (GTLE) on aluminium chloride (AlCl3 ) neurotoxicity in rats. All solutions were injected into the cornu ammonis region 1 hippocampal region. We measured the performance of active avoidance (AA) tasks, various enzyme activities and total glutathione content (TGC) in the forebrain cortex (FbC), striatum, basal forebrain (BFb), hippocampus, brain stem and cerebellum. AlCl3 markedly reduced AA performance and activities of cytochrome c oxidase (COX) and acetylcholinesterase (AChE) in all regions. It decreased TGC in the FbC, striatum, BFb, hippocampus, brain stem and cerebellum, and increased superoxide dismutase activity in the FbC, cerebellum and BFb. GTLE pretreatment completely reversed the damaging effects of AlCl3 on AA and superoxide dismutase activity, markedly corrected COX and AChE activities, and moderately improved TGC. GTLE alone increased COX and AChE activities in almost all regions. GTLE reduces AlCl3 neurotoxicity probably via antioxidative effects and improves mitochondrial and cholinergic synaptic functions through the actions of (-)-epigallocatechin gallate and (-)-epicatechin, compounds most abundantly found in GTLE. Our results suggest that green tea might be beneficial in Alzheimer's disease.

Maternal deprivation causes CaMKII downregulation and modulates glutamate, norepinephrine and serotonin in limbic brain areas in a rat model of single prolonged stress.

BACKGROUND: Early life stress is a major risk factor for later development of psychiatric disorders, including post-traumatic stress disorder (PTSD). An intricate relationship exists between various neurotransmitters (such as glutamate, norepinephrine or serotonin), calcium/calmodulin-dependent protein kinase II (CaMKII), as an important regulator of glutamatergic synaptic function, and PTSD. Here, we developed a double-hit model to investigate the interaction of maternal deprivation (MD) as an early life stress model and single prolonged stress (SPS) as a PTSD model at the behavioral and molecular levels. METHODS: Male Wistar rats exposed to these stress paradigms were subjected to a comprehensive behavioral analysis. In hippocampal synaptosomes we investigated neurotransmitter release and glutamate concentration. The expression of CaMKII and the content of monoamines were determined in selected brain regions. Brain-derived neurotrophic factor (BDNF) mRNA was quantified by radioactive in situ hybridization. RESULTS: We report a distinct behavioral phenotype in the double-hit group. Double-hit and SPS groups had decreased hippocampal presynaptic glutamatergic function. In hippocampus, double-hit stress caused a decrease in autophosphorylation of CaMKII. In prefrontal cortex, both SPS and double-hit stress had a similar effect on CaMKII autophosphorylation. Double-hit stress, rather than SPS, affected the norepinephrine and serotonin levels in prefrontal cortex, and suppressed BDNF gene expression in prefrontal cortex and hippocampus. LIMITATIONS: The study was conducted in male rats only. The affected brain regions cannot be restricted to hippocampus, prefrontal cortex and amygdala. CONCLUSION: Double-hit stress caused more pronounced and distinct behavioral, molecular and functional changes, compared to MD or SPS alone.

Serum levels of interleukin-6 and tumor necrosis factor-alpha in exacerbation and remission phase of schizophrenia.

BACKGROUND: The variations in proinflamatory cytokine levels have been associated with schizophrenia (SCH), duration of illness, psychopathology and treatment. The aim of the study was to investigate serum levels of interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α) in schizophrenic patients during exacerbation and remission, and its association with course of illness and therapy. SUBJECTS AND METHODS: We measured serum levels of IL-6 and TNF-α in 43 schizophrenic patients in exacerbation and remission and compared them to 29 healthy controls, matched by sex, age, body mass index (BMI) and smoking habits. The severity of psychopathology was assessed using the Positive and Negative Syndrome Scale (PANSS). RESULTS: There was no difference in levels of IL-6 and TNF-α in exacerbation compared to remission in schizophrenic patients. IL-6 was higher and TNF-α was lower in schizophrenic patients in both exacerbation and remission in comparison with healthy controls. TNF-α in exacerbation was in negative correlation with IL-6 in remission. No statistical significance was found between levels of cytokines and sex, age, BMI, smoking habits, antipsychotic medication, duration of treatment and duration of illness. IL-6 levels were in positive correlation with the age of onset and the duration of untreated psychosis. In schizophrenic patients on adjunctive treatment with mood stabilizers, TNF-α levels increased in remission. CONCLUSION: Our results suggest that the connection between schizophrenia, cytokines and medication is multifaceted, and not necessarily linear. Adjunct mood stabilizers not only ameliorate psychopathology, but might convey immunomodulatory effects as well. Further longitudinal studies could elucidate potential beneficial effect of combined therapy in treatment of SCH.

Decreased Plasma Levels of Kynurenine and Kynurenic Acid in Previously Treated and First-Episode Antipsychotic-Naive Schizophrenia Patients.

Tryptophan (TRP) catabolites exert neuroactive effects, with the plethora of evidence suggesting that kynurenic acid (KYNA), a catabolite of the kynurenine pathway (KP), acts as the regulator of glutamate and acetylcholine in the brain, contributing to the schizophrenia pathophysiology. Newer evidence regarding measures of KP metabolites in the blood of schizophrenia patients and from the central nervous system suggest that blood levels of these metabolites by no means could reflect pathological changes of TRP degradation in the brain. The aim of this study was to investigate plasma concentrations of TRP, kynurenine (KYN) and KYNA at the acute phase and remission of schizophrenia in a prospective, case-control study of highly selected and matched schizophrenia patients and healthy individuals. Our study revealed significantly decreased KYN and KYNA in schizophrenia patients (p < 0.001), irrespective of illness state, type of antipsychotic treatment, number of episodes or illness duration and no differences in the KYN/TRP ratio between schizophrenia patients and healthy individuals. These findings could be interpreted as indices that kynurenine pathway might not be dysregulated in the periphery and that other factors contribute to observed disturbances in concentrations, but as our study had certain limitations, we cannot draw definite conclusions. Further studies, especially those exploring other body compartments that participate in kynurenine pathway, are needed.

Matrix metalloproteinase-2 (MMP-2) and -9 (MMP-9) in preoperative serum as independent prognostic markers in patients with colorectal cancer.

Colorectal cancer is one of the leading causes of cancer related death in developed countries. One of the reasons is the absence of tumor specific diagnostic and prognostic markers. The aim of this study was to examine the correlation of matrix metalloproteinase-2 (MMP-2) and -9 (MMP-9) expressions in serum and clinicopathological features of the colorectal adenocarcinoma. Another aim was to examine expression of MMP-9 in the tissue of the colorectal carcinoma in MMP-9 serum positive patients. In addition, we tried to establish the correlation between preoperative levels of serum markers (CEA and CA 19-9) and presence of MMP-2 or MMP-9. The study was performed on 32 patients with colorectal adenocarcinoma who underwent surgery and 11 patients in a control group who were operated for benign diseases. The samples were analyzed by SDS-PAGE to determine the molecular mass and SDS-PAGE zymography to determine levels of MMP-2 and MMP-9. Expression of MMP-9 was determined immunohistochemically in the tissue of the colorectal carcinoma of MMP-9 serum positive patients. MMP-2 and MMP-9 levels were increased in the serum of the patients with colorectal cancer compared to the control group. There was significant correlation in MMPs levels among the patients with tumor stage I and II and the patients with tumor stage III and IV. Obtained results did not demonstrate correlation between levels of CEA, CA 19-9 and presence of MMP-2 or MMP-9. MMP-9 expression was positive in 85% of MMP-9 serum positive patients with colorectal carcinoma. The overexpression of MMP-2 and MMP-9 strongly suggests its association with colorectal adenocarcinoma. Detection of MMP-2 and MMP-9 in serum might be useful for identification of patients with higher risk for colorectal cancer recurrence.

Maternal Deprivation in Rats Decreases the Expression of Interneuron Markers in the Neocortex and Hippocampus.

Early life stress has profound effects on the development of the central nervous system. We exposed 9-day-old rat pups to a 24 h maternal deprivation (MD) and sacrificed them as young adults (60-day-old), with the aim to study the effects of early stress on forebrain circuitry. We estimated numbers of various immunohistochemically defined interneuron subpopulations in several neocortical regions and in the hippocampus. MD rats showed reduced numbers of parvalbumin-expressing interneurons in the CA1 region of the hippocampus and in the prefrontal cortex, compared with controls. Numbers of reelin-expressing and calretinin-expressing interneurons were also reduced in the CA1 and CA3 hippocampal areas, but unaltered in the neocortex of MD rats. The number of calbinin-expressing interneurons in the neocortex was similar in the MD rats compared with controls. We analyzed cell death in 15-day-old rats after MD and found no difference compared to control rats. Thus, our results more likely reflect the downregulation of markers than the actual loss of interneurons. To investigate synaptic activity in the hippocampus we immunostained for glutamatergic and inhibitory vesicular transporters. The number of inhibitory synapses was decreased in the CA1 and CA3 regions of the hippocampus in MD rats, with the normal number of excitatory synapses. Our results indicate complex, cell type-specific, and region-specific alterations in the inhibitory circuitry induced by maternal deprivation. Such alterations may underlie symptoms of MD at the behavioral level and possibly contribute to mechanisms by which early life stress causes neuropsychiatric disorders, such as schizophrenia.

Attenuation of cold restraint stress-induced gastric lesions by an olive leaf extract.

Olive leaf extract (OLE) possesses, among other, antioxidative properties, but whether it influences gastroprotection against stress-induced gastric lesions remains unknown. In this study we investigated the protective effect of OLE, a natural antioxidant, on gastric mucosal damage induced by cold restraint stress (CRS) in rats. Three different doses of commercial OLE EFLA((R)) 943 were applied intragastrically (i.g.) 30 min prior to stress induction. Macroscopic gastric lesions were evaluated and ulcer index (UI) was calculated. Histological evidence of gastric mucosal lesions was also obtained. Concentration of malondialdehyde (MDA) as an index of lipid peroxidation, and catalase (CAT) and superoxide dismutase (SOD) activities were determined in gastric mucosa. The effects of applied OLE on gastric mucosal lesions, lipid peroxidation and antioxidative enzymes activity were compared with effects of i.g. pretreatment of reference drug, ranitidine. CRS caused severe gastric lesions in all non-pretreated animals, and this finding was confirmed histologicaly. Pretreatment with OLE (40, 80 and 120 mg.kg(-1)), as well as with ranitidine (50 mg.kg(-1)), significantly (p < 0.001) attenuated stress-induced gastric lesions. Treatment with 80 mg.kg(-1) of OLE was the most effective in prevention of rise in gastric MDA level and decrease in CAT and SOD activity. The results obtained indicate that OLE possesses gastroprotective activity against CRS-induced gastric lesions in rats, possibly related to its antioxidative properties.

Acetylcholinesterase as a potential target of acute neurotoxic effects of lindane in rats.

The aim of our study was to investigate the possible involvement of acetylcholinesterase (AchE) in mediating the early phase of acute lindane neurotoxicity in rats. Male Wistar rats (n = 48) were divided into following groups: 1. control, saline-treated group; 2. dimethylsulfoxidetreated group; 3. group that received lindane dissolved in dimethylsulfoxide, in a dose of 8 mg/kg intraperitoneally. Eight animals from each group were sacrificed 0.5 and 4 h after treatment and brain samples were prepared for further analysis. AchE activity (mitochondrial and synaptosomal fraction) was determined in cerebral cortex, thalamus, hippocampus and nc. caudatus spectrophotometrically. A significant increase in mitochondrial AchE activity was detected in cortex and nc. caudatus of lindane-treated animals 0.5 h after administration (p < 0.05). This rise was sustained in nc. caudatus within 4 h after treatment (p < 0.05). In contrast, activity of synaptosomal AchE fraction was significantly increased only in thalamus 4 h after lindane administration (p < 0.05). An increase in AchE activity may be involved in mediating acute neurotoxic effects of lindane, at least in some brain structures in rats.

Short-term sleep fragmentation enhances anxiety-related behavior: The role of hormonal alterations.

INTRODUCTION: The neuroendocrine background of acute sleep fragmentation in obstructive sleep apnea and sleep fragmentation involvement in psychiatric comorbidities, common in these patients, are still largely unknown. The aim of this study was to determine the effects of short-term experimental sleep fragmentation on anxiety -like behavior and hormonal status in rats. METHODS: Male rats were adapted to treadmill (ON and OFF mode with belt speed set on 0.02m/s and 0.00m/s) and randomized to: 1) treadmill control (TC, only OFF mode); 2) motion, activity control (AC, 10min ON and 30min OFF mode) and 3) sleep fragmentation (SF, 30s ON and 90s OFF mode) group. Six hours later, the animals were tested in the open field, elevated plus maze and light/dark test (n = 8/group). Testosterone, estradiol, progesterone and corticosterone were determined in separate animal cohort immediately upon sleep fragmentation (n = 6/group). RESULTS: SF rats showed decreased rearings number, decreased time spent in the central area and increased thigmotaxic index compared to TC and AC rats in the open field test. Similarly, increased anxiety upon sleep fragmentation was observed in the elevated plus maze and the light/dark test. Significantly lower testosterone, estradiol and progesterone levels were determined in SF in comparison to AC and TC groups, while there was no significant difference in the levels of corticosterone. CONCLUSION: Short term sleep fragmentation enhances anxiety-related behavior in rats, which could be partly mediated by the observed hormonal changes presented in the current study in form of testosterone, estradiol and progesterone depletion.

Low bone mineral density and high bone metabolism turnover in premenopausal women with unipolar depression.

INTRODUCTION AND HYPOTHESIS: The majority of studies reporting decreased bone mineral density (BMD) in patients with unipolar depression neglected sex and age differences and menopause as the most important risk factor for osteoporosis. We presumed that physically healthy premenopausal women with unipolar depression have decreased BMD and altered bone cell metabolism. METHODS: BMD at lumbar spine and femoral neck by dual X-ray absorptiometry, bone alkaline phosphatase sera activity, 5b-tartarate resistant acid phosphatase sera activity and urine N-terminal telopeptide were measured in 73 premenopausal women with unipolar depression and compared with 47 healthy, age- and osteoporosis risk factors-matched premenopausal women. The duration and severity of depression, hormonal status (cortisol, prolactin, parathormone, oestradiol), antidepressive treatment, and physical activity through whole and modified QUALEFFO-41 questionnaire were evaluated. The results were statistically elaborated by the chi-square test, Student's t-test for independent samples, one-way analysis of variance - ANOVA, one-sample Kolmogorov-Smirnov test. Correlations were assessed by means of Pearson's coefficient. RESULTS: Patients with unipolar depression had significantly lower BMD, the decrease of which correlated only with the duration of depression. High bone metabolism turnover was found with a predomination of osteoresorption which, but not osteosynthesis, correlated with the severity of depression, estimated through Hamilton depression scores. Despite higher but not significant levels of cortisol in women with unipolar depression, the BMD decrease and high bone turnover seem not to be the consequence of hormonal changes or medical treatment. The significant correlations between physical activity and osteoresorption markers were found indicating possible underlying mechanism. CONCLUSIONS: Premenopausal women with unipolar depression have significantly lower BMD because of stimulated bone cell metabolism with predomination of osteoresorption process, mostly due to decreased physical activity in depression. These women should be investigated for osteoporosis and the multidisciplinary team approach is advocated.

Plasma homocysteine levels in young male patients in the exacerbation and remission phase of schizophrenia.

High levels of homocysteine (Hcy) were suggested to contribute to the pathogenesis of schizophrenia. Recent investigations have shown that treatment with folic acid, vitamin B-12 and pyridoxine are effective in reducing Hcy levels while concomitantly reducing the score of positive and negative symptoms in schizophrenic patients. In addition to the availability of nutrients (mainly folate, vitamins B6 and B12), plasma Hcy concentrations are dependent on complex metabolic regulation that could be disrupted in schizophrenia. This study was designed to test the influence of disease activity on plasma Hcy levels. Plasma Hcy concentrations were measured in male chronic schizophrenic patients with a predominantly positive (SCH (+)) or predominantly negative (SCH (-)) syndrome in schizophrenia immediately upon admission to the hospital (exacerbation phase) and one month later (remission phase). During this period patients received antipsychotic medications without vitamin therapy. The effects of age, duration of illness, folate and B12 concentrations, as well as smoking and coffee consumption habits on the observed changes were evaluated. Age- and sex-matched subjects were included in the control group. In the control group plasma Hcy concentration was 8.75+/-1.84 micromol/L. In the exacerbation phase plasma Hcy concentrations were significantly increased both in SCH (+) (14.91+/-6.19 micromol/L) and SCH (-) groups (12.8+/-3.27 micromol/L). There was no difference in plasma Hcy concentrations between SCH (+) and SCH (-) patients. Serum folate and B12 concentrations were not significantly different in any of the investigated groups of subjects. The plasma Hcy concentrations could not be correlated with age, duration of illness, the score of positive symptoms or the concentration of folate and vitamin B12. A positive correlation was found between plasma Hcy level and score of negative symptoms in both groups of patients. No correlation was found between smoking or coffee consumption habits and plasma Hcy concentrations. All patients exhibited decreased plasma Hcy levels in the remission phase of the illness, with a mean decrease of 2.68+/-1.57 micromol/L. Folate and B12 levels did not differ in the exacerbation and remission phases of the illness. The significant decrease of plasma Hcy levels, without changes in folate and vitamin B12 concentrations in the remission phase of schizophrenia, could indicate an influence of a pathogenetic process involved in schizophrenia on Hcy metabolism.