Social memory,amnesia, and autism: Brain oxytocin secretion is regulated by NAD+ metabolites and single nucleotide polymorphisms of CD38

Previously, we demonstrated that CD38, a transmembrane protein with ADP-ribosyl cyclase activity, plays a critical role in mouse social behavior by regulating the release of oxytocin (OXT), which is essential for mutual recognition. When CD38 was disrupted, social amnesia was observed in Cd38 knockout mice. The autism spectrum disorders (ASDs), characterized by defects in reciprocal social interaction and communication, occur either sporadically or in a familial pattern. However, the etiology of ASDs remains largely unknown. Therefore, the theoretical basis for pharmacological treatments has not been established. Hence, there is a rationale for investigating single nucleotide polymorphisms (SNPs) in the human CD38 gene in ASD subjects. We found several SNPs in this gene. The SNP rs3796863 (C > A) was associated with high-functioning autism (HFA) in American samples from the Autism Gene Resource Exchange. Although this finding was partially confirmed in low-functioning autism subjects in Israel, it has not been replicated in Japanese HFA subjects. The second SNP of interest, rs1800561 (4693C > T), leads to the substitution of an arginine (R) at codon 140 by tryptophan (W; R140W) in CD38. This mutation was found in four probands of ASD and in family members of three pedigrees with variable levels of ASD or ASD traits. The plasma levels of OXT in ASD subjects with the R140W allele were lower than those in ASD subjects lacking this allele. The OXT levels were unchanged in healthy subjects with or without this mutation. One proband with the R140W allele receiving intranasal OXT for approximately 3 years showed improvement in areas of social approach, eye contact and communication behaviors, emotion, irritability, and aggression. Five other ASD subjects with mental deficits received nasal OXT for various periods; three subjects showed improved symptoms, while two showed little or no effect. These results suggest that SNPs in CD38 may be possible risk factors for ASD by abrogating OXT function and that some ASD subjects can be treated with OXT in preliminary clinical trials.     

Intranasal oxytocin,but not vasopressin,augments neural responses to toddlers in human fathers

This study investigates paternal brain function with the hope of better understanding the neural basis for variation in caregiving involvement among men. The neuropeptides oxytocin (OT) and vasopressin (AVP) are implicated in paternal caregiving in humans and other species. In a double-blind, placebo-controlled, within-subject pharmaco-functional MRI experiment, we randomized 30 fathers of 1–2 year old children to receive either 24 IU intranasal OT before one scan and placebo before the other scan (n = 15) or 20 IU intranasal AVP before one scan and placebo before the other scan (n = 15). Brain function was measured with fMRI as the fathers viewed pictures of their children, unknown children and unknown adults, and as they listened to unknown infant cry stimuli. Intranasal OT, but not AVP, significantly increased the BOLD fMRI response to viewing pictures of own children within the caudate nucleus, a target of midbrain dopamine projections, as well as the dorsal anterior cingulate (dACC) and visual cortex, suggesting that intranasal oxytocin augments activation in brain regions involved in reward, empathy and attention in human fathers. OT effects also varied as a function of order of administration such that when OT was given before placebo, it increased activation within several reward-related structures (substantia nigra, ventral tegmental area, putamen) more than when it was given after placebo. Neither OT nor AVP had significant main effects on the neural response to cries. Our findings suggest that the hormonal changes associated with the transition to fatherhood are likely to facilitate increased approach motivation and empathy for children, and call for future research that evaluates the potential of OT to normalize deficits in paternal motivation, as might be found among men suffering from post-partum depression.     

The satiety signal oleoylethanolamide stimulates oxytocin neurosecretion from rat hypothalamic neurons

The anandamide monounsaturated analogue oleoylethanolamide (OEA) acts as satiety signal released from enterocytes upon the ingestion of dietary fats to prolong the interval to the next meal. This effect, which requires intact vagal fibers and intestinal PPAR-alpha receptors, is coupled to the increase of c-fos and oxytocin mRNA expression in neurons of the paraventricular nucleus (PVN) and is prevented by the intracerebroventricular administration of a selective oxytocin antagonist, thus suggesting a necessary role of oxytocinergic neurotransmission in the pro-satiety effect of OEA. By brain microdialysis and immunohistochemistry, in this study we demonstrate that OEA treatment can stimulate oxytocin neurosecretion from the PVN and enhance oxytocin expression at both axonal and somatodendritic levels of hypothalamic neurons. Such effects, which are maximum 2 h after OEA administration, support the hypothesis that the satiety-inducing action of OEA is mediated by the activation of oxytocin hypothalamic neurons.     

Combining oxytocin administration and positive emotion inductions: Examining social perception and analytical performance

Intranasal administration of the hypothalamic neuropeptide oxytocin (OT) has, in some studies, been associated with positive effects on social perception and cognition. Similarly, positive emotion inductions can improve a range of perceptual and performance-based behaviors. In this exploratory study, we examined how OT administration and positive emotion inductions interact in their associations with social and analytical performance. Participants (N = 124) were randomly assigned to receive an intranasal spray of OT (40 IU) or placebo and then viewed one of three videos designed to engender one of the following emotion states: social warmth, pride, or an affectively neutral state. Following the emotion induction, participants completed social perception and analytical tasks. There were no significant main effects of OT condition on social perception tasks, failing to replicate prior research, or on analytical performance. Further, OT condition and positive emotion inductions did not interact with each other in their associations with social perception performance. However, OT condition and positive emotion manipulations did significantly interact in their associations with analytical performance. Specifically, combining positive emotion inductions with OT administration was associated with worse analytical performance, with the pride induction no longer benefiting performance and the warmth induction resulting in worse performance. In sum, we found little evidence for main or interactive effects of OT on social perception but preliminary evidence that OT administration may impair analytical performance when paired with positive emotion inductions.     

Male‐specific alteration in excitatory post‐synaptic development and social interaction in pre‐natal valproic acid exposure model of autism spectrum disorder

Autism spectrum disorder (ASD) is a pervasive developmental disorder characterized by three main behavioral symptoms including social deficits, impaired communication, and stereotyped and repetitive behaviors. ASD prevalence shows gender bias to male. Prenatal exposure to valproic acid (VPA), a drug used in epilepsy and bipolar disorder, induces autistic symptoms in both human and rodents. As we reported previously, prenatally VPA‐exposed animals at E12 showed impairment in social behavior without any overt reproductive toxicity. Social interactions were not significantly different between male and female rats in control condition. However, VPA‐exposed male offspring showed significantly impaired social interaction while female offspring showed only marginal deficits in social interaction. Similar male inclination was observed in hyperactivity behavior induced by VPA. In addition to the ASD‐like behavioral phenotype, prenatally VPA‐exposed rat offspring shows crooked tail phenotype, which was not different between male and female groups. Both male and female rat showed reduced GABAergic neuronal marker GAD and increased glutamatergic neuronal marker vGluT1 expression. Interestingly, despite of the similar increased expression of vGluT1, post‐synaptic marker proteins such as PSD‐95 and α‐CAMKII expression was significantly elevated only in male offspring. Electron microscopy showed increased number of post‐synapse in male but not in female at 4 weeks of age. These results might suggest that the altered glutamatergic neuronal differentiation leads to deranged post‐synaptic maturation only in male offspring prenatally exposed to VPA. Consistent with the increased post‐synaptic compartment, VPA‐exposed male rats showed higher sensitivity to electric shock than VPA‐exposed female rats. These results suggest that prenatally VPA‐exposed rats show the male preponderance of ASD‐like behaviors including defective social interaction similar to human autistic patients, which might be caused by ectopic increase in glutamatergic synapses in male rats.     

Corticosterone may interact with peripubertal development to shape adult resistance to social defeat

Studies of social stress in adult mice have revealed two distinct defeat-responsive behavioral phenotypes; “susceptible” and “resistant,” characterized by social avoidance and social interaction, respectively. Typically, these phenotypes are observed at least 1 day after the last defeat in adults, but may extend up to 30 days later. The current study examined the impact of peripubertal social defeat on immediate (1 day) and adult (30 day) social stress phenotypes and neuroendocrine function in male C57BL/6 mice. Initially, peripubertal (P32) mice were resistant to social defeat. When the same mice were tested for social interaction again as adults (P62), two phenotypes emerged; a group of mice were characterized as susceptible evidenced by significantly lower social interaction, whereas the remaining mice exhibited normal social interaction, characteristic of resistance. A repeated analysis of corticosterone revealed that the adult (P62) resistant mice had elevated corticosterone following the social interaction test as juveniles. This was when all mice, regardless of adult phenotype, displayed equivalent levels of social interaction. Peripubertal corticosterone was positively correlated with adult social interaction levels in defeated mice, suggesting early life stress responsiveness impacts adult social behavior. In addition, adult corticotropin-releasing factor (CRF) mRNA in the paraventricular nucleus of the hypothalamus (PVN) was elevated in all defeated mice, but there were no differences in CRF mRNA expression between the phenotypes. Thus, there is a delayed appearance of social stress-responsive phenotypes suggesting that early life stress exposure, combined with the resultant physiological responses, may interact with pubertal development to influence adult social behavior.     

Dexamethasone exposure affects paraventricular nucleus and pituitary corticotrophs in female rat fetuses: An unbiased stereological and immunohistochemical study

The hypothalamic paraventricular nucleus (PVN) drives the stress response by activating the hypothalamo-pituitary-adrenal (HPA) axis, particularly vulnerable to glucocorticoid exposure during development. To evaluate the effects of fetal dexamethasone (Dx) exposure on the stereological features of PVN and HPA axis activity in female rat fetuses, pregnant rats received 0.5 mg Dx/kg/b.w./day on days 16, 17 and 18 of pregnancy and 21-day-old fetuses were obtained; controls received the same volume of saline. In an unbiased stereological approach, Cavalieri’s principle and an optical fractionator were used for estimating volume and total cell number of the PVN, respectively. The intensity of corticotropin-releasing hormone (CRH) immunoreactivity in the median eminence (ME) was determined by CRH optical density and the adrenocorticotropic hormone (ACTH) relative fluorescence signal intensity (RIF) in pituitary corticotrophs was measured using Image J. Significant reductions (p < 0.05) in PVN volume and cell number were found in fetuses exposed to Dx. Additionally, CRH optical density in the ME and ACTH RIF (p < 0.05) in the corticotrophs were decreased. The established results suggest that the reduced number of cells in the PVN after maternal Dx administration negatively affects the CRH content in the ME and the ACTH quantity in pituitary corticotrophs in near-term fetuses.     

Role of α-CGRP in the regulation of neurotoxic responses induced by kainic acid in mice

Kainic acid (KA) is an excitatory and neurotoxic substance. The role of α-calcitonin gene-related peptide (α-CGRP) in the regulation of KA-induced hippocampal neuronal cell death was investigated in the present study. The intracerebroventricular (i.c.v.) administration with KA (0.07 μg) increased hippocampal α-CGRP mRNA level in ICR mice. The α-CGRP mRNA level began to increase at 1 h, reached at maximal level at 6 and 12 h, and returned to the control level by 24 h after i.c.v. administration with KA. In addition, KA-induced hippocampal CA3 neuronal death in C57BL6 (wild type) group was more pronounced compared to KA-induced hippocampal CA3 pyramidal cell death in α-CGRP knock-out (KO) group. Furthermore, sumatriptan, a CGRP releasing inhibitor, significantly protected the pyramidal cell death in CA3 hippocampal region induced by KA administered i.c.v. in ICR mice. Our results suggest that α-CGRP may play an important role in the regulation of KA-induced pyramidal cell death in CA3 region of the hippocampus.     

Interactive effect of galanin-like peptide (GALP) and spontaneous exercise on energy metabolism

Galanin-like peptide (GALP) is a neuropeptide involved in energy metabolism. The interactive effect of GALP and exercise on energy metabolism has not been investigated. The aim of this study was to determine if energy metabolism in spontaneously exercising mice could be promoted by intracerebroventricular (ICV) GALP administration. Changes in respiratory exchange ratio in response to GALP ICV administration indicated that lipids were primarily consumed followed by a continuous consumption of glucose throughout the dark period in non-exercising mice. In mice permitted to spontaneously exercise on a running-wheel, GALP ICV administration increased the consumed oxygen volume and heat production level from 5 to 11 h after administration. These effects occurred independently from the total running distance. The interaction between GALP ICV administration and spontaneous exercise decreased body weight within 24 h (F_(1,16) = 5.772, p < 0.05), with no significant interaction observed regarding food and water intake or total distance. Energy metabolism-related enzymes were assessed in liver and skeletal muscle samples, with a significant interaction on mRNA expression between GALP ICV administration and spontaneous exercise observed in phosphoenolpyruvate carboxykinase (F_(1,16) = 18.602, p < 0.001) that regulates gluconeogenesis and glucose transporter-4 (F_(1,16) = 21.092, p < 0.001). GALP significantly decreased the mRNA expression of sterol regulatory element-binding protein-1c (p < 0.05) that regulates fatty acid synthesis regardless of spontaneous exercise with no changes to acetyl-CoA carboxylase a and fatty acid synthetase. These results indicate the GALP ICV administration can further promote energy metabolism when administered to spontaneously exercising mice.     

Salivary vasopressin increases following intranasal oxytocin administration

Extant research has documented the effects of intranasal administration of oxytocin (OT), and to a lesser degree Arginine Vasopressin (AVP) – two structurally-related neuropeptides – on brain and behaviour, yet the effects of exogenous manipulation of one on circulating levels of the other remain unknown. Studies have shown that OT administration impacts the peripheral levels of numerous hormones; however, whether OT administration also increases AVP concentrations has not been explored. Utilizing a double-blind placebo-controlled within-subject design, ten male and female subjects provided ten saliva samples over four consecutive hours: at baseline and nine times following OT administration. Results indicate that salivary AVP increased in the first hour following OT manipulation (OT condition: mean AVP = 2.17 pg/ml, SE = 28, placebo condition: mean AVP = 1.42 pg/ml, SE = .18) but returned to baseline levels at the next assessment (80 min) and remained low for the remaining period. Similar to OT, AVP showed high degree of individual stability and baseline levels of AVP correlated with AVP concentrations at the first and second post-administration hours regardless of drug condition (Pearson r = .85–.93). Validity of salivary AVP ELISA measurement was verified by demonstrating individual stability of salivary AVP over a six-month period (r = .70, p < .000) as well correlation with plasma levels over the same period (r = .32, p = .037) in a sample of 45 young adults who did not participate in the current study. Overall, findings suggest a potential crosstalk between OT and AVP and indicate that baseline levels of the two neuropeptides may shape the degree to which these systems respond to exogenous manipulation.     

Effects of an H3R Antagonist on the Animal Model of Autism Induced by Prenatal Exposure to Valproic Acid

Autism spectrum disorders (ASD) are a group of neurodevelopmental disorders primarily characterized by impaired social interaction and communication, and by restricted repetitive behaviors and interests. Ligands of histamine receptor 3 (H3R) are considered potential therapeutic agents for the treatment of different brain disorders and cognitive impairments. Considering this, the aim of the present study is to evaluate the actions of ciproxifan (CPX), an H3R antagonist, on the animal model of autism induced by prenatal exposure to valproic acid (VPA). Swiss mice were prenatally exposed to VPA on embryonic day 11 and assessed for social behavior, nociceptive threshold and repetitive behavior at 50 days of life. The treatment with CPX (3 mg/kg) or saline was administered 30 minutes before each behavioral test. The VPA group presented lower sociability index compared to VPA animals that were treated with CPX. Compared to the Control group, VPA animals presented a significantly higher nociceptive threshold, and treatment with CPX was not able to modify this parameter. In the marble burying test, the number of marbles buried by VPA animals was consistent with markedly repetitive behavior. VPA animals that received CPX buried a reduced amount of marbles. In summary, we report that an acute dose of CPX is able to attenuate sociability deficits and stereotypies present in the VPA model of autism. Our findings have the potential to help the investigations of both the molecular underpinnings of ASD and of possible treatments to ameliorate the ASD symptomatology, although more research is still necessary to corroborate and expand this initial data.     

Progesterone improves neurocognitive outcomes following therapeutic cranial irradiation in mice

Despite improved therapeutic methods, CNS toxicity resulting from cancer treatment remains a major cause of post-treatment morbidity. More than half of adult patients with cranial irradiation for brain cancer develop neurobehavioral/cognitive deficits that severely impact quality of life. We examined the neuroprotective effects of the neurosteroid progesterone (PROG) against ionizing radiation (IR)-induced neurobehavioral/cognitive deficits in mice. Male C57/BL mice were exposed to one of two fractionated dose regimens of IR (3 Gy × 3 or 3 Gy × 5). PROG (16 mg/kg; 0.16 mg/g) was given as a pre-, concurrent or post-IR treatment for 14 days. Mice were tested for short- and long-term effects of IR and PROG on neurobehavioral/cognitive function on days 10 and 30 after IR treatment. We evaluated both hippocampus-dependent and -independent memory functions. Locomotor activity, elevated plus maze, novel object recognition and Morris water maze tests revealed behavioral deficits following IR. PROG treatment produced improvement in behavioral performance at both time points in the mice given IR. Western blot analysis of hippocampal and cortical tissue showed that IR at both doses induced astrocytic activation (glial fibrillary acidic protein), reactive macrophages/microglia (CD68) and apoptosis (cleaved caspase-3) and PROG treatment inhibited these markers of brain injury. There was no significant difference in the degree of deficit in any test between the two dose regimens of IR at either time point. These findings could be important in the context of patients with brain tumors who may undergo radiotherapy and eventually develop cognitive deficits.     

Nicotine improves ethanol-induced memory impairment: The role of dorsal hippocampal NMDA receptors

AimsThe current study was undertaken to determine the role of dorsal hippocampal N-methyl-d-aspartate (NMDA) receptors in nicotine's effect on impairment of memory by ethanol.Main methodsAdult male mice were cannulated in the CA1 regions of dorsal hippocampi and trained on a passive avoidance learning task for memory assessment.Key findingsWe found that pre-training intraperitoneal (i.p.) administration of ethanol (0.5 and 1 g/kg) decreased memory retrieval when tested 24 h later. Pre-test administration of ethanol reversed the decrease in inhibitory avoidance response induced by pre-training ethanol. Similar to ethanol, pre-test administration of nicotine (0.125–0.75 mg/kg, s.c.) prevented impairment of memory by pre-training ethanol. In the animals that received ethanol (1 g/kg, i.p) before training and tested following intra-CA1 administration of different doses of NMDA (0.0005–0.005 µg/mouse), no significant change was observed in the retrieval latencies. Co-administration of the same doses of NMDA with an ineffective dose of nicotine (0.125 mg/kg, s.c.) significantly improved the memory retrieval and mimicked the effects of pre-test administration of a higher dose of nicotine. Pre-test intra-CA1 microinjection of MK-801 (0.25–1 µg/mouse), which had no effect alone, in combination with an effective dose of nicotine (0.75 mg/kg, s.c.) prevented the improving effect of nicotine on memory impaired by pre-training ethanol. Moreover, intra-CA1 microinjection of MK-801 reversed the NMDA-induced potentiation of the nicotine response.SignificanceThe results suggest the importance of NMDA glutamate system(s) in the CA1 regions of dorsal hippocampus for improving the effect of nicotine on the ethanol-induced amnesia.     

Involvement of the oxytocin system in the nucleus accumbens in the regulation of juvenile social novelty-seeking behavior

Exploration of novel environments, stimuli, and conspecifics is highly adaptive during the juvenile period, as individuals transition from immaturity to adulthood. We recently showed that juvenile rats prefer to interact with a novel individual over a familiar cage mate. However, the neural mechanisms underlying this juvenile social novelty-seeking behavior remain largely unknown. One potential candidate is the oxytocin (OXT) system, given its involvement in various motivated social behaviors. Here, we show that administration of the specific oxytocin receptor antagonist desGly-NH₂,d(CH₂)₅-[Tyr(Me)²,Thr⁴]OVT reduces social novelty seeking-behavior in juvenile male rats when injected into the nucleus accumbens (10 ng/0.5 μl/side). The same drug dose was ineffective at altering social novelty-seeking behavior when administered into the lateral septum or basolateral amygdala. These results are the first to suggest the involvement of the OXT system in the nucleus accumbens in the regulation of juvenile social novelty-seeking behavior.     

Perinatal effects of exposure to PCBs on social preferences in young adult and middle-aged offspring mice

In social species, social interactions between conspecifics constitute a fundamental component to establish relations, provide best chances to reproduce, and even improve survival rates. In this study, a three-chambered social approach test was used to estimate the level of sociability and level of preference for social novelty in both male and female young adult (postnatal day (PND) 50) and middle-aged (PND 330) offspring mice (n = 10 per group) that were perinatally exposed to a mixture of six polychlorinated biphenyls (PCBs), 28, 52, 101, 138, 153, and 180, at environmentally low doses (10 and 1000 ng/kg b.w. for dams during gestation and lactation), a profile that closely mimics human exposure to contaminated fish. Our results showed that PCBs bidirectionally modulated social preferences in offspring mice, and the effects were sex and age dependent. However, increased levels of social interactions were rather frequently detected in both assays of the three-chambered test. Reduced social interaction was only induced in 1000 ng/kg PCB-exposed middle-aged males, which exhibited similar preferences to social and non-social stimuli when compared to middle-aged controls. Furthermore, results showed that plasma levels of both corticosterone and acetylcholinesterase activity were higher in all PCB-exposed middle-aged males and females than in their control counterparts. In summary, although the effects of PCBs were only of moderate magnitude, our results suggest that a PCB mixture can act as an endocrine disruptor in offspring mice, disturbing the formation of normal social habits.     

Sub-arachnoid ketamine administration combined with or without misoprostol/oxytocin to facilitate cervical dilation in ewes: A case study

The cervical anatomy limits the use of trans-cervical artificial insemination (AI) and embryo transfer in ewes. Thus, the objective of the study was to evaluate the sub-arachnoid administration of ketamine as a tool to be used in cervical dilation of the ewe. The following experimental treatments were used: in Experiment 1, animals (n = 6) were treated with the sub-arachnoid administration of ketamine (KS, 1.5 mg kg⁻¹); and in Experiment 2, one tablet of misoprostol was diluted in 1.5 ml saline and deposited near the cervical os, 5 h before the trial + oxytocin administered i.v. 5 min before the reproductive procedures (MO, 200 + 20 U.I., respectively). In Experiment 3, animals received sub-arachnoid ketamine + misoprostol/oxytocin (KSMO). The systemic effects, analgesia, sedation, and motor neuron block were evaluated before each experiment and at pre-determined time intervals thereafter. A subjective score system was used to assess pain and discomfort during the reproductive manipulations in the different experiments. The mean duration of analgesia in the sternal decubitus position without sedation was 30 ± 4 and 25 ± 7 min for the KS and KSMO treatments, respectively. All treatments provided sufficient cervical dilation for the passage of the insemination rod into the uterus. The ketamine sub-arachnoid treatment alone produced a complete cervical dilation, allowing easy passage of the rod. Further studies are needed to establish whether this anesthetic technique may interfere with fertility, pregnancy or lambing rate in ewes during AI or embryo transfer.     

Oxytocin promotes intuitive rather than deliberated cooperation with the in-group

A contribution to a special issue on Hormones and Human Competition.In intergroup settings, individuals prefer cooperating with their in-group, and sometimes derogate and punish out-groups. Here we replicate earlier work showing that such in-group bounded cooperation is conditioned by oxytocin and extend it by showing that oxytocin-motivated in-group cooperation is intuitive rather than deliberated. Healthy males (N = 65) and females (N = 129) self-administered intranasal placebo or 24 IU oxytocin in a double-blind placebo-controlled between-subjects design, were assigned to a three-person in-group (that faced a 3-person out-group), and given an endowment from which they could contribute to a within-group pool (benefitting the in-group), and/or to a between-group pool (benefitting the in-group and punishing the out-group). Prior to decision-making, participants performed a Stroop Interference task that was either cognitively taxing, or not. Cognitively taxed individuals kept less to themselves and contributed more to the within-group pool. Furthermore, participants receiving placebo contributed more to the within-group pool when they were cognitively taxed rather than not; those receiving oxytocin contributed to the within-group pool regardless of cognitive taxation. Neither taxation nor treatment influenced contributions to the between-group pool, and no significant sex differences were observed. It follows that in intergroup settings (i) oxytocin increases in-group bounded cooperation, (ii) oxytocin neither reduces nor increases out-group directed spite, and (iii) oxytocin-induced in-group cooperation is independent of cognitive taxation and, therefore, likely to be intuitive rather than consciously deliberated.     

Effect of total flavonoids of Radix Ilicis pubescentis on cerebral ischemia reperfusion model

This paper aims to observe the effects of total flavonoids of Radix Ilicis pubescentis on mouse model of cerebral ischemia reperfusion. Mice were orally given different doses of total flavonoids of Radix Ilicis pubescentis 10 d, and were administered once daily. On the tenth day after the administration of 1 h in mice after anesthesia, we used needle to hook the bilateral common carotid artery (CCA) for 10 min, with 10 min ischemia reperfusion, 10 min ischemia. Then we restored their blood supply, copy the model of cerebral ischemia reperfusion; We then had all mice reperfused for 24 h, and then took their orbital blood samples and measured blood rheology. We quickly removed the brain, with half of the brain having sagittal incision. Then we fixed the brains and sectioned them to observe the pathological changes of brain cells in the hippocampus and cortex. We also measured the other half sample which was made of brain homogenate of NO, NOS, Na⁺-K⁺-, ATP enzyme Mg²⁺-ATPase and Ca²⁺-ATPase. Acupuncture needle hook occlusion of bilateral common carotid arteries can successfully establish the model of cerebral ischemia reperfusion. After comparing with the model mice, we concluded that Ilex pubescens flavonoids not only reduce damage to the brain nerve cells in the hippocampus and cortex, but also significantly reduce the content of NO in brain homogenate, the activity of nitric oxide synthase (NOS) and increases ATP enzyme activity (P < 0.05, P < 0.01). In this way, cerebral ischemia reperfusion injury is improved. Different dosages of Ilex pubescens flavonoids on mouse cerebral ischemia reperfusion model have good effects.     

Kososan,a standardized traditional Japanese herbal medicine,reverses sleep disturbance in socially isolated mice via GABAA-benzodiazepine receptor complex activation

PurposeKososan (KSS), a traditional Japanese medicine with a distinct aroma, is clinically used to treat affective disorders but its antidepressant-like effect has not been thoroughly investigated. In this study, we investigated the effects of inhaled and orally administered KSS on sleep disturbances in socially isolated mice.MethodsFour-weeks-old male ddy mice were housed either in social isolation or in groups for 4–6 weeks before the experiment. KSS was orally administered (0.5 or 1.0 g/kg) or inhaled (0.5, 1.0, or 2.5 g/0.125 m³) 60 min before pentobarbital administration. Stress levels in mice were evaluated by the duration of pentobarbital-induced sleeping time.ResultsSleeping time was shorter in socially-isolated mice than in group-housed mice. Oral and inhaled KSS prolonged sleeping time in stressed mice, but had no effect on sleeping time of group-housed mice. Prolonged sleeping time after oral KSS was significantly inhibited (p < 0.05) by bicuculline (3 mg/kg, i.p.), a GABA_A antagonist, but not by flumazenil (3 mg/kg, i.p.), a selective benzodiazepine antagonist. Prolonged sleeping time after KSS inhalation was significantly inhibited (p < 0.05) by flumazenil but not by bicuculline.ConclusionsOur findings suggest that KSS activates GABA_A-benzodiazepine receptor complex and reverses shortened pentobarbital-induced sleep caused by social isolation.     

Neuroprotective effect of allicin against traumatic brain injury via Akt/endothelial nitric oxide synthase pathway-mediated anti-inflammatory and anti-oxidative activities

Allicin, one of the main biologically active compounds derived from garlic, has been shown to exert various anti-oxidative and anti-inflammatory activities in in vitro and in vivo studies. Here, we sought to investigate the potential neuroprotective effects of allicin against traumatic brain injury (TBI) in rats. We found that allicin treatment (10 and 50 mg/kg, not 1 mg/kg) significantly reduced brain edema and motor functional deficits, as well as apoptotic neuronal cell death in injured cortex. These protective effects could be observed even if the administration was delayed to 4 h after injury. Moreover, allicin treatment decreased the expression levels of MDA and protein carbonyl, preserved the endogenous antioxidant enzyme activities, and suppressed the expression of inflammatory cytokines. The results of Western blot analysis showed that allicin increased the phosphorylation of Akt and endothelial nitric oxide synthase (eNOS). Blocking Akt/eNOS pathway activation by specific inhibitor LY294002 (10 μL, 10 mmol/L) or L-NIO (0.5 mg/kg) partly reversed the protective effects of allicin and its anti-inflammatory activities. The allicin induced anti-oxidative activity was partly prevented by LY294002, but not L-NIO. In summary, our data strongly suggested that allicin treatment at an appropriate dose can exert protective effect against TBI through Akt/eNOS pathway-mediated anti-inflammatory and anti-oxidative activities.