Effects of the aqueous extract of Pimpinella anisum L. seeds on exploratory activity and emotional behavior in rats using the open field and elevated plus maze tests

Phyllanthus niruri L. Administration during pregnancy and breastfeeding: Maternal evaluation and effects on initial development and adult behavior of male rat offspring

The leaves of Phyllanthus niruri L. are used in folk medicine in many countries to treat various diseases. However, despite the enormous therapeutic potential, use of the plant is contraindicated during pregnancy and breastfeeding. Reports on the impacts of exposure to this plant on the development of the offspring of rats are still scarce and controversial. The aim of this study is to evaluate the effects of the administration of P. niruri aqueous extract, during pregnancy and lactation, on maternal toxicity, on postnatal physical development, and on behavioral aspects in adult male offspring. Pregnant rats were divided into three experimental groups (n = 8/group) and treated daily during pregnancy and lactation, (gavage), with vehicle and doses of 75 and 150 mg/kg of aqueous extract of P. niruri. To assess maternal toxicity; weight gain, feed intake, reproductive outcomes, and biochemical profiles were analyzed. The male pups were evaluated for physical development through the end of lactation and submitted to tests evaluating their behavior in adulthood. Treatment with the aqueous extract of P. niruri (AEPN) did not cause significant changes in the maternal and reproductive parameters analyzed. However, changes in the biochemical markers of liver function were observed. In the male offspring, the extract did not alter postnatal physical growth, but caused early opening of the ear canal and eyes. In the evaluation of adult male offspring, it was found that the groups exposed to AEPN presented behavioral changes predictive of anxiolytic effect. Brain malondialdehyde levels of male offspring whose mothers were treated with AEPN were significantly reduced. Our results demonstrate that exposure to P. niruri extract did not induce significant changes sufficiently to indicate occurrence of maternal or postnatal toxicity. In addition, in the male offspring exposed to the extract, anticipation of physical maturation parameters and anxiolytic-like behavior was observed.

Sugarcane (Saccharum officinarum L.) induces psychostimulant, anxiolytic-like effects and improvement of motor performance in rats

ETHNOPHARMACOLOGICAL RELEVANCE

Sugarcane (Saccharum officinarum L.) is reported by traditional medicine as tonic, stimulating and beneficial in increasing resistance to fatigue. Previous preclinical studies in rats using aqueous extract of sugarcane leaves (AE) revealed pharmacological effects on the central nervous and cardiovascular systems involving the participation of dopaminergic pathways. This neurotransmission system is also related to motor, emotional and cognitive activities, which could, in part, justify the ethnopharmacological information.

AIM OF STUDY

The present study aimed to investigate the motor, emotional and cognitive activities of rats submitted to AE treatment using behavioral tests in order to correlate the pharmacological effects with the therapeutic benefits postulated by traditional medicine. Additionally, the chemical profile of AE was evaluated by HPLC-UV/Vis, and the presence of shikimic acid, vitexin, and ferulic acid, as possible chemical markers, was investigated through comparisons of chemical parameters with the authentic patterns, and a UV-Vis scan of known spectra.

MATERIAL AND METHODS

Rats received water (1.5 mL/kg, p.o.) and AE (0.5, 10 and 500 mg/kg, p.o.) in the absence and presence of haloperidol (0.5 mg/kg, i.p.), 90 min before open field; rotarod; elevated plus maze and inhibitory avoidance tests for investigation of motor; emotional and cognitive responses. As a positive control was used apomorphine (0.25 mg/kg, s.c.). The chemical profile of AE was evaluated by HPLC-UV/Vis and the presence of shikimic acid, vitexin and ferulic acid, as possible chemical markers, was investigated through comparisons with the retention times, an increase of the integral of the peak area determined by co-injection of AE with the authentic patterns, and a UV-Vis scan of known spectra.

RESULTS

In open field, it revealed that AE increased locomotion; reduced rearing but did not change freezing and grooming. Besides, AE increased motor performance in rotarod and reduced anxiety in elevated plus maze. A relation dose-response was observed in these tests where the lowest dose of AE was more effective in developing pharmacological responses. Previous administration of haloperidol inhibited the responses of AE. Inhibitory avoidance test revealed that AE did not modify fast-learning and associative memory.

CONCLUSIONS

Sugarcane induced psychostimulant, anxiolytic-like effects, and improvement of motor performance in rats, with the involvement of dopaminergic pathways. The present study points to AE as a potential adaptogen but, in addition to behavioral assessments, metabolic and molecular aspects, that involve the participation of a variety of regulatory systems, will be investigated in futures studies. Phytochemical analyses showed that AE is a complex matrix and revealed shikimic acid, vitexin, and ferulic acid as potential chemical markers.

Betula pendula Leaf Extract Targets the Interplay between Brain Oxidative Stress, Inflammation, and NFkB Pathways in Amyloid Aβ1-42-Treated Rats

Alzheimer's disease (AD) is known as the primary and most common cause of dementia in the middle-aged and elderly population worldwide. Chemical analyses of B. pendula leaf extract (BPE), performed using spectrophotometric and chromatographic methods (LC/MS), revealed high amounts of polyphenol carboxylic acids (gallic, chlorogenic, caffeic, trans-p-coumaric, ferulic, and salicylic acids), as well as flavonoids (apigenin, luteolin, luteolin-7-O-glucoside, naringenin, hyperoside, quercetin, and quercitrin). Four groups of Wistar rats were used in this experiment (n = 7/group): control (untreated), Aβ1-42 (2 μg/rat intracerebroventricular (i.c.v.), Aβ1-42 + BPE (200 mg/Kg b.w.), and DMSO (10 μL/rat). On the first day, one dose of Aβ1-42 was intracerebroventricularly administered to animals in groups 2 and 3. Subsequently, BPE was orally administered for the next 15 days to group 3. On the 16th day, behavioral tests were performed. Biomarkers of brain oxidative stress Malondialdehyde (MDA), (Peroxidase (PRx), Catalase (CAT), and Superoxid dismutase (SOD) and inflammation (cytokines: tumor necrosis factor -α (TNF-α), Interleukin 1β (IL-1β), and cyclooxygenase-2 (COX 2)) in plasma and hippocampus homogenates were assessed. Various protein expressions (Phospho-Tau (Ser404) (pTau Ser 404), Phospho-Tau (Ser396) (pTau Ser 396), synaptophysin, and the Nuclear factor kappa B (NFkB) signaling pathway) were analyzed using Western blot and immunohistochemistry in the hippocampus. The results show that BPE diminished lipid peroxidation and neuroinflammation, modulated specific protein expression, enhanced the antioxidant capacity, and improved spontaneous alternation behavior, suggesting that it has beneficial effects in AD.

Syringic acid alleviates valproic acid induced autism via activation of p38 mitogen-activated protein kinase: Possible molecular approach

Autism spectrum disorder (ASD) is a multifactorial neurodevelopmental disorder characterized by restrictive and repetitive behavior followed by impairment in social, verbal, and non-verbal interaction and communication. Valproic acid (VPA) is a well-known anti-epileptic drug, but its prenatal exposure to animals causes social impairment, neurotransmitters imbalance, and neuroinflammation with ASD-like phenotypes. Syringic acid (SA) is a polyphenolic compound with anti-inflammatory, anti-apoptotic, antioxidant, and neuromodulator activity. The purpose of study was to investigate the protective effect of Syringic acid (SA) in prenatal VPA-treated rats through behavioral, neuroinflammation, oxidative stress, neurotransmitters, neuronal integrity, and apoptotic marker. Single dose of VPA was administered 600 mg/kg, i.p. on a gestational day (GD) 12th and SA was administrated from PnD 26th to 54th at the dose of 25, 50, and 100 mg/kg, p.o. On PnD 56th behavioral parameters (Pain sensitivity, open field test, narrow beam walks test and social impairment test) were performed and all animals were sacrificed, and brain tissue was isolated for oxidative stress (GSH, CAT, and LPO), neuroinflammation (TNF-α and IL-6) and neurotransmitters (GABA and Glutamate), histopathology (H&E, Nissl), immunohistochemistry (p38 MAPK) analysis. Rat treated with SA dose-dependently prevented behavioral alteration, restored antioxidant enzymes, neurotransmitters level, decreased neuroinflammatory markers, and improved neuronal integrity. Furthermore, immunohistochemistry confirmed the reduced p38 MAPK marker expression by SA in VPA induced autistic behavior.

Neurotoxicity of Bisphenol A and the Impact of Melatonin Administration on Oxidative Stress, ERK/NF-kB Signaling Pathway, and Behavior in Rats

Bisphenol A (BPA) exposure can be associated with neurodevelopmental disorders due to impairment of cell proliferation and synaptic development. Our study evaluated the effects of melatonin (MEL) on ambulatory activity, lipid peroxidation, cytokines, ERK/NF-kB signaling pathway in the hippocampus and frontal lobe, and histopathological changes in the hippocampus of the BPA-treated rats. The animals were divided into 4 groups: control, BPA, BPA + MEL I, and BPA + MEL II. MEL I (20 mg/kg b.w.) and MEL II (40 mg/kg b.w.) were orally administered for 28 days. On the 29th day, BPA (1 mg/kg b.w.) was intraperitoneally administered, and, after 24 h, an open field test (OFT) and an elevated plus maze (EPM) were conducted. The results showed that the MEL II group made significantly more entries in the open arms of EPM, traveled significantly greater distance, and spent more time in the central part of OFT. Malondialdehyde levels were diminished by MEL II in the hippocampus and by MEL I in the frontal lobe. In the hippocampus, the MAPK level was significantly lowered by both doses of MEL (p < 0.05) while in the frontal lobe, only MEL II reduced the MAPK activation. MEL I and II significantly decreased the γH2AX and upregulated the NFkB and pNFkB expressions in the hippocampus while MEL II downregulated the MCP1 expression. Both doses of MEL attenuated the BPA-evoked histopathological alterations in the hippocampus. These data indicate that MEL can mediate the neuroprotection against BPA-induced neurotoxicity and improves behavioral changes suggesting a real potential as a protective agent in brain toxicity.

Under or Absent Reporting of Light Stimuli in Testing of Anxiety-Like Behaviors in Rodents: The Need for Standardization

Behavioral neuroscience tests such as the Light/Dark Test, the Open Field Test, the Elevated Plus Maze Test, and the Three Chamber Social Interaction Test have become both essential and widely used behavioral tests for transgenic and pre-clinical models for drug screening and testing. However, as fast as the field has evolved and the contemporaneous involvement of technology, little assessment of the literature has been done to ensure that these behavioral neuroscience tests that are crucial to pre-clinical testing have well-controlled ethological motivation by the use of lighting (i.e., Lux). In the present review paper, N = 420 manuscripts were examined from 2015 to 2019 as a sample set (i.e., n = ~20–22 publications per year) and it was found that only a meager n = 50 publications (i.e., 11.9% of the publications sampled) met the criteria for proper anxiogenic and anxiolytic Lux reported. These findings illustrate a serious concern that behavioral neuroscience papers are not being vetted properly at the journal review level and are being released into the literature and public domain making it difficult to assess the quality of the science being reported. This creates a real need for standardizing the use of Lux in all publications on behavioral neuroscience techniques within the field to ensure that contributions are meaningful, avoid unnecessary duplication, and ultimately would serve to create a more efficient process within the pre-clinical screening/testing for drugs that serve as anxiolytic compounds that would prove more useful than what prior decades of work have produced. It is suggested that improving the standardization of the use and reporting of Lux in behavioral neuroscience tests and the standardization of peer-review processes overseeing the proper documentation of these methodological approaches in manuscripts could serve to advance pre-clinical testing for effective anxiolytic drugs. This report serves to highlight this concern and proposes strategies to proactively remedy them as the field moves forward for decades to come.

Escitalopram Targets Oxidative Stress, Caspase-3, BDNF and MeCP2 in the Hippocampus and Frontal Cortex of a Rat Model of Depression Induced by Chronic Unpredictable Mild Stress

In recent years, escitalopram (ESC) has been suggested to have different mechanisms of action beyond its well known selective serotonin reuptake inhibition. The aim of this study is to investigate the effects of escitalopram on oxidative stress, apoptosis, brain-derived neurotrophic factor (BDNF), Methyl-CpG-binding protein 2 (MeCP2), and oligodendrocytes number in the brain of chronic unpredictable mild stress-induced depressed rats. The animals were randomised in four groups (8 in each group): control, stress, stress + ESC 5 and stress + ESC 5/10. ESC was administered for 42 days in a fixed dose (5 mg/kg b.w.) or in an up-titration regimen (21 days ESC 5 mg/kg b.w. then 21 days ESC 10 mg/kg b.w.). Sucrose preference test (SPT) and elevated plus maze (EPM) were also performed. ESC improved the percentage of sucrose preference, locomotion and anxiety. ESC5/10 reduced the oxidative damage in the hippocampus and improved the antioxidant defence in the hippocampus and frontal lobe. ESC5/10 lowered caspase 3 activity in the hippocampus. Escitalopram had a modulatory effect on BDNF and the number of oligodendrocytes in the hippocampus and frontal lobe and also improved the MeCP2 expressions. The results confirm the multiple pathways implicated in the pathogenesis of depression and suggest that escitalopram exerts an antidepressant effect via different intricate mechanisms.

Targeting Oxidative Stress Reduction and Inhibition of HDAC1, MECP2, and NF-kB Pathways in Rats With Experimentally Induced Hyperglycemia by Administration of Thymus marshallianus Willd. Extracts

The effects of two lyophilized extracts obtained from the aerial parts of Thymus marschallianus Willd. and harvested from wild flora (TMW) and obtained from culture (TMC) were evaluated in Wistar rats with experimentally induced hyperglycemia. The hyperglycemia was induced by streptozotocin (STZ) administration and the obtained results were evaluated in comparison for TMW and TMC. The polyphenolic composition of extracts was evaluated by spectrophotometrical and LC-MS methods. In vitro antioxidant capacity assays (DPPH, FRAP, EPR) were performed in order to preliminary establish the ability of tested samples to protect against free radical induced damage. Afterwards, the effects of these extracts were assessed in vivo on rats with experimental-induced hyperglycemia. Oxidative stress biomarkers (e.g. malondialdehyde-MDA), phosphorylated transcription factor subunit of nuclear kappaB (NF-kB) p65, methyl CpG binding protein (MECP) 2 and histone deacetylase 1 (HDAC1) expressions in hippocampus and frontal lobe were assessed. Open Field Test (OFT) and Elevated Plus Maze (EPM) were conducted on tested animals. Malondialdehyde (MDA) levels and HDAC1and MeCP2 expressions increased significantly in hippocampus (p<0.05) and frontal lobe (p<0.001) of diabetes group compared to the control group in parallel with decreasing of GSH/GSSG ratio. TMW and TMC administration reduced blood glucose levels and diminished lipid peroxidation, HDAC1 expression and enhanced antioxidant capacity in frontal lobe. TMW improved central locomotion of rats, increased phospho-NFkB p65 and diminished MECP2 expressions in hippocampus. Both tested samples exerted a beneficial effect by increasing the antioxidant defense. Our findings indicate that the administration of these extracts might represent a good option in the treatment of diabetes and its complications.

The Modulatory Effect of Metformin on Ethanol-Induced Anxiety, Redox Imbalance, and Extracellular Matrix Levels in the Brains of Wistar Rats

The study investigated the potential neuroprotective effects of metformin (MET) on alcohol-induced neurotoxicity in adult Wistar rats. The animals were randomized in four groups (n = 10): control, alcohol (ALC), ALC + MET, and MET. ALC (2 g/kg b.w.) and MET (200 mg/kg b.w.) were orally administered for 21 days, once daily. For the ALC + MET group, MET was administered 2 h after ALC treatment. On day 22, the open field test (OFT) and elevated plus maze (EPM) were performed. MET improved global activity and increased the time spent in unprotected open arms, decreased oxidative stress, both in the frontal lobe and in the hippocampus, and increased neuroglobin expression in the frontal cortex. Histopathologically, an increased neurosecretory activity in the frontal cortex in the ALC + MET group was noticed. Thus, our findings suggest that metformin has antioxidant and anxiolytic effects and may partially reverse the neurotoxic effects induced by ethanol.

Low-dose alcohol ameliorated homocysteine-induced anxiety-related behavior via attenuating oxidative stress in mice

Recent studies showed that homocysteine (Hcy) levels were obviously elevated in patients with anxiety, furthermore, oxidative stress and inflammation were closely linked with Hcy-related damage. Despite alcohol exposure has differential effects on different forms of anxiety, the role of alcohol on anxiety-related behavior induced by high Hcy levels is still not entirely clear. The present study investigated the protective potential of low-dose alcohol against homocysteine-induced anxiety-related behavior and explored the possible underlying mechanisms. Mice were administered intragastrically with methionine (2.0 g/kg/day) or alcohol (0.6 g/kg/day). After 21 days of administration, the anxiety-related behavior was evaluated through open field (OF) and elevated plus maze (EPM) tests, and the variations of oxidative stress and inflammation levels were measured. The results of OF and EPM tests showed that the anxiety-related behavior in mice was prevented by alcohol treatment. Alcohol lowered the elevated serum Hcy levels and alleviated the damage of hippocampal tissues in hyperhomocysteinemia (HHcy) mice. Meanwhile, the superoxide dismutase (SOD) activity of the hippocampal tissues enhanced, and the malondialdehyde (MDA) concentration of the hippocampal tissues and the serum interleukin-1β (IL-1β) level decreased. In addition, after administering alcohol, the increase of superoxide dismutase 1 (SOD1), heme oxygenase 1 (HO-1) protein expression and the decrease of IL-1β protein expression were also detected in HHcy mice hippocampal tissues. Taken together, low-dose alcohol significantly ameliorated the Hcy-induced anxiety-related behavior in mice, which might be related to SOD1 and HO-1 upregulation and IL-1β downregulation.

Pharmacological evaluation of the hydro-alcoholic extract of Campomanesia phaea fruits in rats

Campomanesia phaea (Myrtaceae), popularly known as cambuci, is one of several species of plants producing comestible fruits, largely used in human nutrition. Despite its consumption and economic potential, limited scientific research is available on the Campomanesia, especially those related to its therapeutic benefits. It is reported by traditional medicine the use of the plant in the treatment of different disorders, such as cardiovascular and nervous system disturbances. So, the aim of this study was to carry out the pharmacological evaluation of the hydro-alcoholic extract (HAE) of Campomanesia fruits in rats by screening consisting of tests: a) neuropharmacological observation, b) test on the cardiovascular system. The HAE, prepared from the extraction of fruits with water/ethanol, was concentrated and freeze-dried. Behavioral responses in rats were investigated in open field test and the cardiovascular actions were investigated by a register of indirect blood pressure and the register of spontaneous beating rate right atrium. The results revealed that HAE induced grooming, hypotension and bradycardia. So, this study identified an action on the central nervous system, represented by grooming, and a cardiovascular activity of Campomanesia. The hypotension, attributed in part to bradycardia, was not related to a cholinergic effect, discarding a possible cholinomimetic action of the plant that could justify both cardiovascular and central actions.

Resveratrol ameliorates brain injury via the TGF-β-mediated ERK signaling pathway in a rat model of cerebral hemorrhage

Brain injury is the most common intracranial injury in human cerebrovascular disease, which may lead to ischemic stroke. Resveratrol induces ameliorative effects in the treatment of certain human diseases by regulating different signaling pathways. The present study assessed the therapeutic effects of resveratrol and its potential mechanism of action in the neurons from rats with ischemia/reperfusion-induced cerebral hemorrhage. The rat model of cerebral hemorrhage was established and reverse transcription-quantitative polymerase chain reaction, western blotting, immunohistochemistry and terminal deoxynucleotidyl-transferase-mediated dUTP nick end labeling assays were subsequently performed to assess the therapeutic effects of resveratrol. The results demonstrated that treatment with resveratrol (10 mg/kg/day) decreased cerebral water content, hippocampal cell apoptosis and cerebral infarct volume compared with the PBS-treated group. Resveratrol treatment also increased neuronal cell viability, improved neurological function and blood brain barrier disruption compared with the PBS group following 21 days of treatment. The administration of resveratrol was demonstrated to decrease the levels of certain inflammatory factors, including ionized calcium binding adaptor molecule 1 and myeloperoxidase, in rats with cerebral hemorrhage. The results revealed that treatment with resveratrol regulated neuronal apoptosis by downregulating the transforming growth factor-β (TGF-β)-mediated extracellular signal-regulated kinase (ERK) signaling pathway. In conclusion, these results indicate that resveratrol decreases ischemia/reperfusion-induced neuronal apoptosis by downregulating the TGF-β-mediated ERK pathway in a rat model of cerebral hemorrhage and may serve as a potential agent for the treatment of cerebral hemorrhage.

Preclinical investigation of the cardiovascular actions induced by aqueous extract of Pimpinella anisum L. seeds in rats

ETHNOPHARMACOLOGY RELEVANCE

Pimpinella anisum is used in traditional medicine because of its pharmacological properties which include cardiovascular action. However, no scientific information supports this use.

AIM OF THE STUDY

This study investigated the effects of Pimpinella on arterial blood pressure (BP) and its pharmacological mechanism of action.

MATERIAL AND METHODS

Pimpinella seeds were extracted with water, concentrated and freeze-dried yielding the aqueous extract (AE). A non-invasive BP assessment method was used (via the caudal artery) on Wistar, Wistar Kyoto, SHRs and rats that were submitted to high intake of dietary salt. Direct BP and heart rate were evaluated in Wistar rats in the absence or presence of atropine, L-NAME and angiotensin II. Spontaneous diuresis and the effect of AE on depolarized portal vein of Wistar rats was also examined.

RESULTS

The data revealed that AE reduced BP in all groups evaluated and its effects were not due to diuretic, sympatholytic or parasympathomimetic actions. Additionally, it was shown that AE does not act as an angiotensin receptor blocker and does not induce hypotension by reducing vascular resistance induced by oxide nitric. In the depolarized portal vein, AE inhibited calcium influx, which indicates that AE acts as calcium channel blocker.

CONCLUSION

This study validates the cardiovascular actions of Pimpinella and characterizes the hypotensive effects of Pimpinella that are related to the blockade of calcium channels.

Effect of Conjugated Linoleic Acid on Memory and Reflex Maturation in Rats Treated During Early Life

In the critical period of neurodevelopment (gestation and lactation), maternal consumption of essential fatty acids (FAs) can alter the offspring cognitive function permanently causing damage. Lipids can regulate neurotrophin and compose brain tissue. However, the effects of maternal consumption of a mixture of conjugated linoleic acid (CLA) on an offspring nervous system are not completely clear. We aimed to investigate the impacts of different CLA concentrations mixed into the maternal diet during early life on neonatal reflex maturation and cognitive functions of the offspring. Three groups were formed: control (CG): receiving a standard diet; CLA1: receiving a diet containing 1% of CLA, and CLA3: receiving a diet containing 3% of CLA, offered during gestation and lactation. After birth, the reflex responses of the offspring were observed from the 1st to the 21st day. After weaning, the animals' anxiety and memory were assessed using open field (OF) and novel object recognition tests. Fatty acids in the breast milk and the offspring's brain were also quantified. The data were analyzed using one-way ANOVA and the Kruskal-Wallis test. CLA1 presented accelerated palmar grasp disappearance versus CLA3 and negative-geotaxis versus CG; and the CLA3 presented increases for most reflexes (cliff-avoidance, vibrissa-placing, negative-geotaxis, and auditory-startle response), and decrease in reflexes palmar grasp and free-fall righting versus CG (p < 0.05). CLA3 group explored less of the OF in the second exposure. CLA1 and CLA3 presented an increased exploration ratio for new objects, which indicates memory improvement. The milk tested from CLA3 demonstrated an increase in polyunsaturated fatty acids (PUFAs), and a decrease in monounsaturated fatty acids. The amount of CLA in milk was greater in CLA1 and CLA3 and in the brain offspring both presented moderated amounts of CLA. Maternal treatment with the CLA mixture induced anticipated reflex maturation and improved memory in the offspring. Even though CLA was detected in the brains in only trace amounts, offspring's brain PUFA and SFA levels were increased. Further studies aimed to delineate the effect of maternal CLA supplementation on offspring's brain lipid metabolism and long-term neurologic outcome are needed to confirm these findings.

Simvastatin improves cerebrovascular injury caused by ischemia‑reperfusion through NF‑κB‑mediated apoptosis via MyD88/TRIF signaling

Cerebrovascular injury is the most prevalent human cerebrovascular disease and frequently results in ischemic stroke. Simvastatin may be a potential therapeutic agent for the treatment of patients with cerebrovascular injury. The present study aimed to investigate the efficacy of and the potential mechanisms regulated by simvastatin in a rat model of ischemia-reperfusion (I/R)-induced cerebrovascular injury. Cerebrovascular injury model rats were established and were subsequently treated with simvastatin or a vehicle control following I/R injury. Cell damage, neurological functions and neuronal apoptosis were examined, as well as the nuclear factor (NF)-κB-mediated myeloid differentiation primary response protein 88 (MyD88)/toll-interleukin-1 receptor domain-containing adapter molecule 1 (TRIF) signaling pathway following simvastatin treatment. The results of the present study demonstrated that simvastatin treatment led to a reduction in cell damage, improvement of neurological functions and decreased neuronal apoptosis compared with vehicle-treated I/R model rats, 14 days post-treatment. In addition, simvastatin treatment reduced cerebral water content and blood-brain barrier disruption in cerebrovascular injury induced by I/R. The results also revealed that simvastatin treatment inhibited neuronal apoptosis via the NF-κB-mediated MyD88/TRIF signaling pathway. In conclusion, simvastatin treatment may reduce I/R-induced neuronal apoptosis via inhibition of the NF-κB-mediated MyD88/TRIF signaling pathway.

Beneficial effects of environmental enrichment on behavior, stress reactivity and synaptophysin/BDNF expression in hippocampus following early life stress

Exposure to environmental enrichment can beneficially influence the behavior and enhance synaptic plasticity. The aim of the present study was to investigate the mediated effects of environmental enrichment on postnatal stress-associated impact with regard to behavior, stress reactivity as well as synaptic plasticity changes in the dorsal hippocampus. Wistar rat pups were submitted to a 3 h maternal separation (MS) protocol during postnatal days 1-21, while another group was left undisturbed. On postnatal day 23, a subgroup from each rearing condition (maternal separation, no-maternal separation) was housed in enriched environmental conditions until postnatal day 65 (6 weeks duration). At approximately three months of age, adult rats underwent behavioral testing to evaluate anxiety (Elevated Plus Maze), locomotion (Open Field Test), spatial learning and memory (Morris Water Maze) as well as non-spatial recognition memory (Novel Object Recognition Test). After completion of behavioral testing, blood samples were taken for evaluation of stress-induced plasma corticosterone using an enzyme-linked immunosorbent assay (ELISA), while immunofluorescence was applied to evaluate hippocampal BDNF and synaptophysin expression in dorsal hippocampus. We found that environmental enrichment protected against the effects of maternal separation as indicated by the lower anxiety levels and the reversal of spatial memory deficits compared to animals housed in standard conditions. These changes were associated with increased BDNF and synaptophysin expression in the hippocampus. Regarding the neuroendocrine response to stress, while exposure to an acute stressor potentiated corticosterone increases in maternally-separated rats, environmental enrichment of these rats prevented this effect. The current study aimed at investigating the compensatory role of enriched environment against the negative outcomes of adverse experiences early in life concurrently on emotional and cognitive behaviors, HPA function and neuroplasticity markers.

Curcumin Reverses the Diazepam-Induced Cognitive Impairment by Modulation of Oxidative Stress and ERK 1/2/NF-κB Pathway in Brain

Oxidative stress and inflammation can be involved in cognitive dysfunction associated with neurodegenerative disorders. Diazepam (DZP) administration has been chosen to simulate the memory impairment. The aim of this study was to evaluate the effects of curcumin (CUR) on spatial cognition, ambulatory activity, and blood and brain oxidative stress levels. The ERK/NF-κB signaling pathway and the histopathological changes in the hippocampus and frontal lobe, in diazepam-treated rats, were also analyzed. The animals were divided into 4 groups: control, carboxymethylcellulose (CMC) + CUR, CMC + DZP, and CUR + CMC + DZP. CUR (150 mg/kg b.w.) was orally administered for 28 days. DZP (2 mg/kg b.w.) was intraperitoneally administered 20 minutes before the behavioral tests (open field test, Y-maze, and elevated plus maze). CUR improved the spontaneous alternation behavior, decreased the oxidative stress levels, both in the blood and in the hippocampus, and downregulated the extracellular signal-regulated kinase (ERK 1/2)/nuclear transcription factor- (NF-) κB/pNF-κB pathway in the hippocampus and the iNOS expression in the hippocampus and frontal lobe of the DZP-treated rats. Histopathologically, no microscopic changes were found. The immunohistochemical signal of iNOS decreased in the DZP and CUR-treated group. Thus, our findings suggest that curcumin administration may improve the cognitive performance and may also have an antioxidant effect.

Maternal intake of cashew nuts accelerates reflex maturation and facilitates memory in the offspring

Essential fatty acids, being indispensable during the stages of pregnancy, lactation and infancy influence the transmission of nerve impulses and brain function, and cashew nuts are a good source of these fatty acids. The objective of this study was to evaluate the effects of cashew nut consumption on reflex development, memory and profile of fatty acids of rat offspring treated during pregnancy and lactation. The animals were divided into three groups: Control (CONT), treated with 7% lipid derived from soybean oil; Normolipidic (NL) treated with 7% lipids derived from cashew nuts; and Hyperlipidic (HL) treated with 20% lipids derived from cashew nuts. Reflex ontogeny, Open-field habituation test and the Object Recognition Test (ORT) were assessed. The profile of fatty acids in the brain was carried out when the animals were zero, 21 and 60days old. Accelerated reflex maturation was observed in animals treated with cashew nuts (p<0.05). NL presented better memory in the Open-field habituation test; the NL and HL showed improvement of short-term memory in the ORT, but long term damage in HL (p<0.05). The results of the lipid profile of the brain at the end of the experiment showed an increase in levels of saturated fatty acids and less Docosahexaenoic acid (DHA) in animals of the HL. The data showed that maternal consumption of cashew nuts can accelerate reflex maturation and facilitate memory in offspring when offered in adequate quantities.