Understanding the Molecular Mechanisms of H2's Regulatory Effect on miR-29s for Brain Protection during Deep Hypothermic Circulatory Arrest.

INTRODUCTION: Research regarding post-operative brain protection after deep hypothermic circulatory arrest (DHCA) has gained attracted significant attention. We previously demonstrated that hydrogen can significantly reverse DHCA-induced brain damage. METHOD: In the current research, we have established the DHCA model successfully using a modified four-vessel occlusion method and injected miR-29s compounds into the hippocampal tissue of rats. RESULT: We were surprised to find hydrogen increased miR-29s expression in the hippocampal tissue of a DHCA rat model. The administration of agomiR-29s counteracted DHCA-induced hippocampal tissue injury, while the antamiR-29s had the opposite effects. CONCLUSION: Based on the above facts, the brain protection mechanism of hydrogen in DHCAtreated rats may be related to the upregulation of miR-29s, which can exert its beneficial effects by alleviating apoptosis, inflammation, and oxidation.

Ameliorative effect and mechanism of curcumin on diabetes model rats with depression / 中国药房

OBJECTIVE To study the ameliorative effect and potential mechanism of curcumin on diabetes model rats with depression based on cAMP response element binding protein （CREB）/brain-derived neurotrophic factor （BDNF） signaling pathway. METHODS The diabetes model rat with depression was established by high fat and high sugar diet+intraperitoneal injection of streptozotocin+chronic unpredictable stress-induced depression. The successfully modeled rats were randomly divided into model group， positive control group （0.18 g/kg metformin and 1.8 mg/kg fluoxetine， gavage）， curcumin low-dose and high-dose groups （30， 60 mg/kg， gavage） and curcumin high-dose+CREB inhibitor group [60 mg/kg curcumin （gavage）+5 mg/kg CREB inhibitor 666-15 （intraperitoneal injection）]， with 12 rats in each group. Another 12 healthy rats were selected as the normal group. Each group was given a corresponding intervention for 4 weeks， the fasting blood glucose level of rats was detected， and the depression of rats was assessed. The levels of corticosterone （CORT） and inflammatory factors [tumor necrosis factor-α （TNF-α）， interleukin- 1β （IL-1β）， IL-6] in serum， and the levels of norepinephrine （NE） and 5-hydroxytryptamine （5-HT） in hippocampal tissue were determined. The pathological changes and neuronal apoptosis were observed in the hippocampal tissue of rats in each group； the expression levels of CREB， BDNF mRNA and protein in hippocampal tissue were detected. RESULTS Compared with the normal group， the hippocampal tissue of rats in the model group was severely damaged， and neurons were scattered， while the fasting blood glucose， the forced swimming immobility time， the tail suspension immobility time， serum levels of CORT， TNF-α， IL-1β and IL-6， and neuron apoptosis indexes were all increased or prolonged significantly （P＜0.05）. The levels of NE and 5-HT， the number of surviving neurons， and the expression levels of CREB and BDNF mRNA and protein in hippocampal tissue were decreased significantly （P＜0.05）. Compared with the 的model group， the damage to hippocampal tissue was relieved in the positive control group and curcumin groups， while the above indexes were improved significantly （P＜0.05）. The improvement effect of curcumin high-dose group was better than that of curcumin low-dose group （P＜0.05）. CREB inhibitor could significantly reverse the ameliorative effect of high-dose curcumin on the model rats （P＜0.05）. CONCLUSIONS Curcumin can improve the depression of diabetes model rats with depression， and relieve neuronal damage and inflammatory response， the mechanism of which may be associated with activating CREB/BDNF signaling pathway.

Aerobic exercise training reduces deep-frying oil-induced apoptosis of hippocampal tissue by reducing oxidative stress in male rats.

Deep-frying oil (DFO) contains high amounts of free radicals, and consuming foods prepared with this method causes damage to nervous tissue due to oxidative stress (OS). Since moderate-intensity aerobic exercise training (AT) reduces OS, the current search investigated the effects of AT on OS, apoptosis, and neurogenesis markers in the hippocampal tissue of DFO-fed rats. Eighteen Wistar male rats (200-280 gr) were randomly allocated to a control group fed with normal food (Con-ND), a control group receiving DFO (Con-DFO), and a group receiving DFO-aerobic exercise (EX-DFO) (n = 6 in each). DFO was gavaged for four weeks, five days a week, with a dose of 2 ml. AT included running on a treadmill for four weeks and five sessions per week (40 min per session). The expression of genes B-cell lymphoma 2 (BCL-2), Protein X associated with Bcl-2 (BAX), Caspase-3 (Casp-3), and Caspase-9 (Casp-9) was measured by PCR method. The ELISA method was used to calculate levels of Superoxide dismutase (SOD) and Catalase (CAT) activity, malondialdehyde (MDA), and Brain-Derived Neurotrophic Factor (BDNF). Also, the expression of the proteins Cannabinoid receptor type 1(CB1), Cannabinoid receptor type2 (CB2), Glial fibrillary acidic protein (GFAP), Neuronal nuclei (NeuN), and DNA fragmentation was evaluated by Immunohistochemical and TUNEL staining. DFO feeding led to a significant increase in apoptotic markers, such as BAX, Casp-3, and Casp-9 gene expression, and DNA fragmentation (p ≤ 0.05) while decreasing BDNF concentration SOD activity (p ≤ 0.05). AT significantly reduced the BAX, Casp-3, Casp-9, MDA, CB1, GFAP, and DNA fragmentation (p ≤ 0.05). In conclusion, AT can reduce the harmful effects of feeding with DFO on the hippocampal tissue.

Vascular determinants of hippocampal viscoelastic properties in healthy adults across the lifespan.

Arterial stiffness and cerebrovascular pulsatility are non-traditional risk factors of Alzheimer's disease. However, there is a gap in understanding the earliest mechanisms that link these vascular determinants to brain aging. Changes to mechanical tissue properties of the hippocampus (HC), a brain structure essential for memory encoding, may reflect the impact of vascular dysfunction on brain aging. We tested the hypothesis that arterial stiffness and cerebrovascular pulsatility are related to HC tissue properties in healthy adults across the lifespan. Twenty-five adults underwent measurements of brachial blood pressure (BP), large elastic artery stiffness, middle cerebral artery pulsatility index (MCAv PI), and magnetic resonance elastography (MRE), a sensitive measure of HC viscoelasticity. Individuals with higher carotid pulse pressure (PP) exhibited lower HC stiffness (ß = -0.39, r = -0.41, p = 0.05), independent of age and sex. Collectively, carotid PP and MCAv PI significantly explained a large portion of the total variance in HC stiffness (adjusted R2 = 0.41, p = 0.005) in the absence of associations with HC volumes. These cross-sectional findings suggest that the earliest reductions in HC tissue properties are associated with alterations in vascular function.

Feeding crocin ameliorate cognitive dysfunction, oxidative stress and neuroinflammation induced by unpredictable chronic mild stress in rats.

INTRODUCTION: The aim of the current study was to investigate the probable mechanism and effect of crocin on brain oxidative damage and memory deficits induced by unpredictable chronic mild stress (UCMS). MATERIALS AND METHODS: Male Wistar rats were randomly divided into six groups consisting of one vehicle group (received normal saline), four groups included rats who received UCMS 4 weeks out of which three groups were pretreated with different doses of crocin (10, 20, and 30 mg/kg/day) concomitantly. To assess the pure effect of crocin, the last experimental group received a high dose of crocin (30 mg/kg/day) without exposure to the UCMS procedure. The behavioral tests including Morris water maze (MWM) and passive avoidance (PA) were performed and eventually they were sacrificed for the estimation of biochemical parameters. RESULTS: The increase in Malondialdehyde (MDA) as an oxidative stress indicator and nitrite levels in the hippocampus were observed in UCMS rats, along with memory deficits in behavioral tests including passive avoidance and Morris water maze (MWM) test. Moreover, treatment with crocin decreased MDA, nitrite, pro-inflammatory cytokine such as TNF-α, and pathological hallmark of Alzheimer's disease including amyloid-ß (Aß), and glial fibrillary acidic protein (GFAP) in the hippocampus, whereas antioxidant agents including total thiol content, SOD, and catalase activity were increased. Also behavioral test demonstrated a positive effect of crocin on memory deficit induced by UCMS. Interlukin-10 as an important anti-inflammatory agent was increased as well. Interestingly, in some behavioral and biochemical findings, treatment with 30 mg/kg of crocin has given better results compared to vehicle group, which means the administration of crocin could have preventive effects on learning and memory impairment. CONCLUSION: The present study strongly confirmed the positive effect of crocin and has the potential as an antioxidant and anti-inflammatory agent that could improve memory impairment induced by UCMS.

Scalp acupuncture Yikang therapy on Baihui (GV20), Sishencong (EX-HN1), Zhisanzhen, Niesanzhen improves neurobehavior in young rats with cerebral palsy through Notch signaling pathway.

OBJECTIVE: To investigate the efficacy of scalp acupuncture Yikang therapy on Baihui (GV20), Sishencong (EX-HN1), Zhisanzhen, Niesanzhen, on neurobehavior in young rats with cerebral palsy based on Notch signaling pathway. METHODS: Thirty 7-day-old rats were randomly divided into sham, model and acupuncture, 10 rats in each group. The cerebral palsy model was established by the accepted modeling method, the acupuncture group selected "Baihui (GV20)", "Sishencong (EX-HN1)", "Zhisanzhen" and "Niesanzhen" for intervention 24 h after the model was made. The body masses were recorded before and after the treatment, respectively. After the intervention, the rats were subjected to suspension experiment, slope experiment, tactile stimulation experiment and Morris water maze experiment. After the end of the experiment, the morphological changes of hippocampal histology were observed by hematoxylin-eosin (HE) staining under light microscope, and the expression of Notch1, Notch3 and Hes5 were detected by Western blot and quantitative real-time polymerase chain reaction (PCR). RESULTS: The changes in body mass of the rats in each group were different; in behavioral experiments, compared with the sham, the suspension time of the model was shortened, the slope experiment, tactile stimulation experiment, and escape latency time were prolonged, and the number of platform crossing was reduced in the model, compared with the model, the suspension time of the acupuncture was prolonged, the slope experiment, tactile stimulation experiment, and escape latency time were shortened, and the number of platform crossing times was increased; HE staining showed severe hippocampal damage in the model and reduced hippocampal damage in the acupuncture. Western Blot and real-time fluorescence quantitative PCR showed that the expression of Notch1, Notch3 and Hes5 were increased in the model and the expression of Notch1, Notch3, Hes5 in acupuncture were decreased. CONCLUSIONS: Scalp acupuncture Yikang therapy may improve neurobehavior and reduce brain injury in rats with cerebral palsy by downregulating the expression of Notch1, Notch3, and Hes5.

MicroRNAs as potential biomarkers in temporal lobe epilepsy and mesial temporal lobe epilepsy.

Temporal lobe epilepsy is the most common form of focal epilepsy in adults, accounting for one third of all diagnosed epileptic patients, with seizures originating from or involving mesial temporal structures such as the hippocampus, and many of these patients being refractory to treatment with anti-epileptic drugs. Temporal lobe epilepsy is the most common childhood neurological disorder and, compared with adults, the symptoms are greatly affected by age and brain development. Diagnosis of temporal lobe epilepsy relies on clinical examination, patient history, electroencephalographic recordings, and brain imaging. Misdiagnosis or delay in diagnosis is common. A molecular biomarker that could distinguish epilepsy from healthy subjects and other neurological conditions would allow for an earlier and more accurate diagnosis and appropriate treatment to be initiated. Among possible biomarkers of pathological changes as well as potential therapeutic targets in the epileptic brain are microRNAs. Most of the recent studies had performed microRNA profiling in body fluids such as blood plasma and blood serum and brain tissues such as temporal cortex tissue and hippocampal tissue. A large number of microRNAs were dysregulated when compared to healthy controls and with some overlap between individual studies that could serve as potential biomarkers. For example, in adults with temporal lobe epilepsy, possible biomarkers are miR-199a-3p in blood plasma and miR-142-5p in blood plasma and blood serum. In adults with mesial temporal lobe epilepsy, possible biomarkers are miR-153 in blood plasma and miR-145-3p in blood serum. However, in many of the studies involving patients who receive one or several anti-epileptic drugs, the influence of these on microRNA expression in body fluids and brain tissues is largely unknown. Further studies are warranted with children with temporal lobe epilepsy and consideration should be given to utilizing mouse or rat and non-human primate models of temporal lobe epilepsy. The animal models could be used to confirm microRNA findings in human patients and to test the effects of targeting specific microRNAs on disease progression and behavior.

Proteomic-Based Approach Reveals the Involvement of Apolipoprotein A-I in Related Phenotypes of Autism Spectrum Disorder in the BTBR Mouse Model.

Autism spectrum disorder (ASD) is a neurodevelopmental disorder. Abnormal lipid metabolism has been suggested to contribute to its pathogenesis. Further exploration of its underlying biochemical mechanisms is needed. In a search for reliable biomarkers for the pathophysiology of ASD, hippocampal tissues from the ASD model BTBR T+ Itpr3tf/J (BTBR) mice and C57BL/6J mice were analyzed, using four-dimensional (4D) label-free proteomic analysis and bioinformatics analysis. Differentially expressed proteins were significantly enriched in lipid metabolic pathways. Among them, apolipoprotein A-I (ApoA-I) is a hub protein and its expression was significantly higher in the BTBR mice. The investigation of protein levels (using Western blotting) also confirmed this observation. Furthermore, expressions of SphK2 and S1P in the ApoA-I pathway both increased. Using the SphK inhibitor (SKI-II), ASD core phenotype and phenotype-related protein levels of P-CREB, P-CaMKII, and GAD1 were improved, as shown via behavioral and molecular biology experiments. Moreover, by using SKI-II, we found proteins related to the development and function of neuron synapses, including ERK, caspase-3, Bax, Bcl-2, CDK5 and KCNQ2 in BTBR mice, whose levels were restored to protein levels comparable to those in the controls. Elucidating the possible mechanism of ApoA-I in ASD-associated phenotypes will provide new ideas for studies on the etiology of ASD.

Protective effects of various doses of Glycyrrhizin on hippocampal tissue of young rats with status epilepticus / 中华实用儿科临床杂志

Objective:To study the protective effects of various doses of Glycyrrhizin on hippocampus of young rats with status epilepticus (SE).Methods:Lithium chloride and pilocarpine were injected intraperitoneally into male Sprague-Dawley (SD) rats (with a postnatal age of 18-21 days), so as to induce SE in rats.The rats were divided into 5 groups according to the random number table method: control group, SE group, SE+ low dose Glycyrrhizin group, SE+ medium dose Glycyrrhizin group and SE+ high dose Glycyrrhizin group.Three different doses of Glycyrrhizin (20 mg/kg, 40 mg/kg and 60 mg/kg) were injected intraperitoneally into the rats.The levels of tumor necrosis factor (TNF)-α, interleukin (IL)-1β and IL-6 in serum of SE rats were determined by enzyme linked immunosorbent assay.Quantitative real-time PCR (qRT-PCR) was used to detect the mRNA expression levels of TNF- α, IL-1β and IL-6 in hippocampus of SE rats.The expression levels of Bax, Bcl-2 and Caspase-3 in hippocampus were detected by Western blot.The damage of neurons was measured by hematoxylin and eosin (HE) staining and Nissl staining.Neurons apoptosis was examined by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL). The mitochondrial changes were observed under transmission electron microscopy.One-way ANOVA followed by Tukey post-hoc test was used for statistical analysis. Results:Compared to the control group, TNF-α[(369.69±58.07) ng/L vs. (75.46±14.64) ng/L], IL-1β[(242.27±25.23) ng/L vs. (45.29±5.90) ng/L] and IL-6[(288.15±24.60) ng/L vs. (46.59±8.80) ng/L] in the serum of SE rats were significantly up-regulated(all P<0.05). Compared to SE group, low, medium and high doses Glycyrrhizin could effectively reduce the levels of TNF-α[(216.67±8.31) ng/L, (158.81±5.03) ng/L and (113.69±12.54) ng/L vs. (369.69±58.07) ng/L], IL-1β[(131.21±5.50) ng/L, (86.60±7.79) ng/L and (65.06±4.39) ng/L vs. (242.27±25.23) ng/L] and IL-6[(150.24±9.48) ng/L, (101.70±5.85) ng/L and (91.60±2.81) ng/L vs. (288.15±24.60) ng/L] released in serum after SE occurred (all P<0.05). The neuronal damage, loss, apoptosis and mitochondrial damage were found in the hippocampus of SE rats.Glycyrrhizin could ameliorate these symptoms.Compared to the control group, Bax levels(0.57±0.01 vs. 0.14±0.01)and Caspase-3 levels(0.54±0.00 vs. 0.11±0.01)in the hippocampus of SE rats were markedly increased, while Bcl-2 levels(0.27±0.01 vs. 0.57±0.02)were decreased(all P<0.05). Compared to the SE group, low, medium and high doses Glycyrrhizin could effectively reduce the levels of Bax(0.51±0.02, 0.45±0.03 and 0.40±0.02 vs. 0.57±0.01)and Caspase-3(0.47±0.02, 0.42±0.02 and 0.37±0.01 vs. 0.54±0.00), and increase the levels of Bcl-2(0.41±0.02, 0.45±0.02 and 0.51±0.01 vs. 0.27±0.01)(all P<0.05). Conclusions:Glycyrrhizin can effectively protect the hippocampus of young rats with SE.

Protective effects of various doses of Glycyrrhizin on hippocampal tissue of young rats with status epilepticus / 中华实用儿科临床杂志

Objective:To study the protective effects of various doses of Glycyrrhizin on hippocampus of young rats with status epilepticus (SE).Methods:Lithium chloride and pilocarpine were injected intraperitoneally into male Sprague-Dawley (SD) rats (with a postnatal age of 18-21 days), so as to induce SE in rats.The rats were divided into 5 groups according to the random number table method: control group, SE group, SE+ low dose Glycyrrhizin group, SE+ medium dose Glycyrrhizin group and SE+ high dose Glycyrrhizin group.Three different doses of Glycyrrhizin (20 mg/kg, 40 mg/kg and 60 mg/kg) were injected intraperitoneally into the rats.The levels of tumor necrosis factor (TNF)-α, interleukin (IL)-1β and IL-6 in serum of SE rats were determined by enzyme linked immunosorbent assay.Quantitative real-time PCR (qRT-PCR) was used to detect the mRNA expression levels of TNF- α, IL-1β and IL-6 in hippocampus of SE rats.The expression levels of Bax, Bcl-2 and Caspase-3 in hippocampus were detected by Western blot.The damage of neurons was measured by hematoxylin and eosin (HE) staining and Nissl staining.Neurons apoptosis was examined by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL). The mitochondrial changes were observed under transmission electron microscopy.One-way ANOVA followed by Tukey post-hoc test was used for statistical analysis. Results:Compared to the control group, TNF-α[(369.69±58.07) ng/L vs. (75.46±14.64) ng/L], IL-1β[(242.27±25.23) ng/L vs. (45.29±5.90) ng/L] and IL-6[(288.15±24.60) ng/L vs. (46.59±8.80) ng/L] in the serum of SE rats were significantly up-regulated(all P<0.05). Compared to SE group, low, medium and high doses Glycyrrhizin could effectively reduce the levels of TNF-α[(216.67±8.31) ng/L, (158.81±5.03) ng/L and (113.69±12.54) ng/L vs. (369.69±58.07) ng/L], IL-1β[(131.21±5.50) ng/L, (86.60±7.79) ng/L and (65.06±4.39) ng/L vs. (242.27±25.23) ng/L] and IL-6[(150.24±9.48) ng/L, (101.70±5.85) ng/L and (91.60±2.81) ng/L vs. (288.15±24.60) ng/L] released in serum after SE occurred (all P<0.05). The neuronal damage, loss, apoptosis and mitochondrial damage were found in the hippocampus of SE rats.Glycyrrhizin could ameliorate these symptoms.Compared to the control group, Bax levels(0.57±0.01 vs. 0.14±0.01)and Caspase-3 levels(0.54±0.00 vs. 0.11±0.01)in the hippocampus of SE rats were markedly increased, while Bcl-2 levels(0.27±0.01 vs. 0.57±0.02)were decreased(all P<0.05). Compared to the SE group, low, medium and high doses Glycyrrhizin could effectively reduce the levels of Bax(0.51±0.02, 0.45±0.03 and 0.40±0.02 vs. 0.57±0.01)and Caspase-3(0.47±0.02, 0.42±0.02 and 0.37±0.01 vs. 0.54±0.00), and increase the levels of Bcl-2(0.41±0.02, 0.45±0.02 and 0.51±0.01 vs. 0.27±0.01)(all P<0.05). Conclusions:Glycyrrhizin can effectively protect the hippocampus of young rats with SE.

Iron Deficiency-Induced Changes in the Hippocampus, Corpus Striatum, and Monoamines Levels That Lead to Anxiety, Depression, Sleep Disorders, and Psychotic Disorders.

Iron deficiency anemia caused by severe iron deficiency in infancy is associated with poor health and severe neurological impairment such as mental, motor, social, emotional, neurophysiological, and neurocognitive dysfunction. The behavioral effects of iron deficiency can present themselves in infancy, but they are also found in adulthood. Some behaviors can start in childhood but persist throughout adulthood. The behaviors that are particularly often seen in infants and children include wariness and hesitance, lack of positive affect, and diminished social engagement. The affected behaviors in adults include anxiety, depression, higher complex cogitative tasks, and other psychological disorders. The mechanisms of how iron deficiency affects behavior include affecting the hippocampus, the corpus striatum, and certain neurotransmitters. The hippocampus is a brain region that is essential for memory, learning, and other purposes. The hippocampus is very sensitive to lack of Iron during early development. The corpus striatum dispatches dopamine-rich projects to the prefrontal cortex, and it is involved in controlling executive activities such as planning, inhibitory control, sustained attention, working memory, regulation of emotion, memory storage and retrieval, motivation, and reward. Iron deficiency has been known to cause changes in behavioral and developmental aspects by affecting neurotransmitters such as serotonin, noradrenaline, and dopamine. Iron deficiency causes behavior changes that can present in infancy and, even if corrected postnatally, it can have long-lasting effects well into adulthood.

Effect of lead exposure on neuroinflammation of hippocampus and cognitive impairment in diabetic rats / 中国职业医学

OBJECTIVE: To explore the effects of lead exposure on inflammatory damage of hippocampus and cognitive impairment in diabetic rats. METHODS: The specific pathogen free(SPF) male healthy Wistar rats were randomly divided into control group and lead-exposed group. The SPF male Goto-Kakisaki Wistar rats rats were randomly divided into diabetes group and diabetes lead-exposed group, with 10 rats in each group. Rats in lead-exposed group and diabetes lead-exposed group were continuously exposed to lead acetate water with a mass fraction of 0.025% for 9 weeks. Rats in control group and diabetes group were given distilled water. The body weight and blood glucose level of rats were measured before lead exposure and at 1, 3, 5, 7 and 9 weeks after exposure. After the exposure, Morris water maze test was used to evaluate the learning and memory ability of rats. The lead levels in whole blood and hippocampal tissues were detected by inductively coupled plasma mass spectrometry, and the expression of mRNA and protein expression of inflammatory factors in hippocampal tissues of rats were detected by real-time fluorescence quantitative polymerase chain reaction and enzyme-linked immunoadsorption, respectively. RESULTS: At the end of lead exposure, the difference of body mass of rats in the diabetes group and the diabetes lead-exposed group was not statistically significant compared with that in the same group before exposure(all P values were >0.05); but the body mass of rats in these two groups was lower than that of the control group and the lead-exposure group(all P values were <0.05). The blood glucose levels of rats were higher in the diabetic group and the diabetes lead-exposed group than that in the control group and the lead-exposed group, respectively(all P values were <0.05). Morris water maze test showed that the escape latency of rats in the 1 st, 2 nd and 3 rd day were longer in diabetes group and the diabetes lead-exposed group than that in the control group and the lead-exposed group(all P values were <0.05). The number of times of crossing platforms were less in the lead-exposed group and the diabetes group than that of the control group(all P values were <0.05). The number of times of crossing platforms was more in the diabetes lead-exposed group than that in the other 3 groups(all P values were <0.05). The levels of lead in blood and hippocampus of rats were higher in the lead-exposed group than those in the control group(all P values were <0.05), and those in the diabetes lead-exposed group were higher than that in the other 3 groups(all P values were <0.05). The relative expression of mRNA of interferon-γ(ifn-γ) and interleukin(il)-6 in hippocampal tissues of rats was higher in the lead-exposed group and the diabetes group than that of the control group(all P values were <0.05). The relative expression of mRNA of tumour necrosis factor-α(tnf-α) and il-1β in the hippocampal tissues of rats was higher in the diabetes group than that of the control group and the lead-exposed group, respectively(all P values were <0.05). The relative expression of mRNA of ifn-γ, tnf-α, il-1β and il-6 in hippocampal tissues of rats was higher in the diabetes lead-exposed group than that of the other 3 groups(all P values were <0.05). The relative protein expression of IFN-γ, TNF-α, IL-4 and IL-6 in hippocampal tissues of rats was higher in lead-exposed group than that of the control group(all P values were <0.05). The relative protein expression of IFN-γ, TNF-α, IL-1β and IL-6 in hippocampal tissues of rats was higher in diabetes group than that of the control group(all P values were <0.05). The relative protein expression of IFN-γ, IL-1β and IL-6 in hippocampal tissues of rats was higher in diabetes group than that of the other 3 groups(all P values were <0.05). CONCLUSION: Diabetes can promote the lead accumulation in the blood and hippocampus of rats. The combined effect of lead exposure and diabetes can up-regulate the expression of pro-inflammatory cytokines in the hippocampal tissues of rats, aggravate the inflammatory response, and have a synergistic effect on the cognitive impairment in rats.

Graphene-Coated Glass Substrate for Continuous Wave Laser Desorption and Atmospheric Pressure Mass Spectrometric Imaging of a Live Hippocampal Tissue.

The atmospheric pressure mass spectrometric (AP-MS) imaging technology combined with an inverted optical microscopic system is a powerful tool for determining the presence and spatial distributions of specific biomolecules of interest in live tissues. Efficient desorption and ionization are essential to acquire mass spectrometric (MS) information in an ambient environment. In this study, we demonstrate a new and efficient desorption process using a graphene-coated glass substrate and a continuous wave (CW) laser for high-resolution AP-MS imaging of a live hippocampal tissue. We found that desorption of biomolecules in a live tissue slice was possible with the aid of a graphene-coated glass substrate and indirect application of a 532 nm CW laser on the graphene substrate. Interestingly, the desorption efficiency of a live tissue on the graphene-coated substrate was strongly dependent on the number of graphene layers. Single-layer graphene was found to be the most sensitive substrate for efficient desorption and reproducible high-resolution hippocampal tissue imaging applications. The subsequent ionization process using nonthermal plasma generated sufficient amounts of molecular ions to obtain high-resolution two-dimensional MS images of the cornu ammonis and the dentate gyrus regions of the hippocampus. Therefore, graphene-coated substrates could be a promising platform to induce an efficient desorption process essential for highly reproducible ambient MS imaging.

Isolation of Neural Stem Cells from the embryonic mouse hippocampus for in vitro growth or engraftment into a host tissue.

For both stem cell research and treatment of the central nervous system disorders, neural stem/progenitor cells (NSPCs) represent an important breakthrough tool. In the expanded stem cell-based therapy use, NSPCs not only provide a powerful cell source for neural cell replacement but a useful model for developmental biology research. Despite numerous approaches were described for isolation of NSPCs from either fetal or adult brain, the main issue remains in extending cell survival following isolation. Here we provide a simple and affordable protocol for making viable NSPCs from the fetal mouse hippocampi, which are capable of maintaining the high viability in a 2D monolayer cell culture or generating 3D neuro-spheroids of cell aggregates. Further, we describe the detailed method for engraftment of embryonic NSPCs onto a host hippocampal tissue for promoting multilinear cell differentiation and maturation within endogenous environment. Our experimental data demonstrate that embryonic NSPCs isolated using this approach show the high viability (above 88%). Within a host tissue, these cells were capable of differentiating to the main neural subpopulations (principal neurons, oligodendrocytes, astroglia). Finally, NSPC-derived neurons demonstrated matured functional properties (electrophysiological activity), becoming functionally integrated into the host hippocampal circuits within a couple of weeks after engraftment.

Improving Effects of Echinacoside on Spatial Cognitive Function in Mice under Hypobaric Hypoxia Environment and Its Mechanism Study / 中国药房

OBJECTIVE： To study the improving effects of echinacoside （ECH） on spatial cognitive function in mice under hypobaric hypoxia environment and its mechanism. METHODS： Totally 60 mice were randomly divided into blank group （normal saline）， model group （normal saline）， positive group （Ginkgo leaf extract tablet，100 mg/kg） and ECH low-dose， medium-dose and high-dose groups （50， 75， 100 mg/kg）， with 10 mice in each group. Except for blank group， other groups were cultured in hypobaric oxygen chamber to simulate hypobaric hypoxia； they were given relevant medicine intragastrically once a day， for consecutive 7 d （Placing into hypobaric oxygen chamber immediately after medication）. Using the times of horizontal and vertical activities of mice in 2 min as index， negative emotions and spatial cognitive function were evaluated. Histopathological changes of hippocampus in mice were observed by microscopy after HE staining. The levels of SOD， CAT， GSH-Px and MDA in hippocampal tissue of mice were detected. RESULTS： Compared with blank group， the times of horizontal activities， MDA level were increased significantly in model group （P＜0.05）， while the times of vertical activities， the levels of SOD， CAT and GSH-Px were decreased significantly （P＜0.05）； the pyramidal cells in the CA1 area of the hippocampal tissue were arranged loosely， and many pyramidal cells were compressed and stained deeply. Compared with model group， the times of horizontal activities and MDA level were decreased significantly in positive group and ECH high-dose group （P＜0.05）， while the times of vertical activities， the levels of SOD， CAT and GSH-Px were increased significantly （P＜0.05）； the pyramidal cells in the CA1 region of the hippocampal tissue were abundant and closely arranged， and a few of them are constricted and deeply stained. CONCLUSIONS： ECH can improve spatial cognitive impairment of mice under hypobaric hypoxia environment， the mechanism of which may be associated with up-regulation of SOD， CAT and GSH-Px， down-regulation of MDA in the hippocampal tissue.

Development of µ-Low-Flow-Push-Pull Perfusion Probes for Ex Vivo Sampling from Mouse Hippocampal Tissue Slices.

This work demonstrates a reduced tip µ-low-flow-push-pull perfusion technique for ex vivo sampling of the extracellular space of mouse hippocampal brain slices. Concentric fused-silica capillary probes are pulled by an in-house gravity puller with a butane flame producing probe tips averaging an overall outer diameter of 30.3 ± 8 µm. The 10-30 nL/min perfusion flow rate through the probe generates an average recovery of 90%. Sampling was performed with mouse brain tissue slices to characterize basal neurotransmitter content in this model system. Samples were collected from hippocampal tissue slices at a volume of 200 nL per sample. Sample arginine, histamine, lysine, glycine, glutamate, and aspartate content was quantified by micellar electrokinetic chromatography with LED-induced fluorescence detection. Primary amine content was sampled over several hours to determine evidence for tissue damage and loss of extracellular content from the tissue slice. Overall, all amino acid concentrations trended lower as an effect of time relative to tissue slicing. There were significant concentration decreases seen for histamine, lysine, and aspartate between time points 0-2 and 2-6 h (p < 0.05) relative to tissue slicing. Analysis of averaged sampling experiments does not appear to reveal significant probe-insertion-related amino acid changes. The work presented shows the applicability of an 80% reduction of probe tip size relative to previous designs for the collection of extracellular content from thin tissue slices.

Seizure liability assessments using the hippocampal tissue slice: Comparison of non-clinical species.

INTRODUCTION: Traditionally, rat hippocampal tissue slice models are used as an in vitro electrophysiology assay to assess seizurogenic potential in early drug development despite non-clinical species-specific differences noted during in vivo seizure studies. METHODS: Hippocampal tissue slices were acutely isolated from rats, minipigs, dogs and nonhuman primates (NHP). Population spikes (PS) were evoked through stimulation of the CA3 Schaffer collateral pathway and recorded using in vitro electrophysiological techniques via an extracellular electrode placed within the CA1 stratum pyramidale cell body layer. RESULTS: Hippocampal slices, across all species, displayed a concentration-dependent increase in PS area and number with the pro-convulsant pentylenetetrazol (PTZ; 0.1-10mM). Beagle dogs exhibited higher sensitivities to PTZ-induced changes in PS area and number compared to both rats and NHPs which presented nuanced differences in their responsiveness to PTZ modulation. Minipigs were comparatively resistant to PTZ-induced changes in both PS area and number. Rat and NHP hippocampal tissues were further characterized with the pro-convulsant agents 4-aminopyradine (4-AP; 1-100µM) and cefazolin (0.001-10mM). Rats possessed higher sensitivities to 4-AP- and cefazolin-induced changes to both PS area and number whereas NHP displayed greater modulation in PS duration. The anti-convulsant agents, diazepam (10-500µM) and lidocaine (1-500µM), were also tested on either rat and/or NHP tissue with both drugs repressing PS activation at high concentrations. DISCUSSION: Hippocampal tissue slices, across all species, possessed distinct sensitivities to pro- and anti-convulsant agents which may benefit the design of non-clinical seizure liability studies and their associated data interpretation.

Molecular Mapping Alzheimer's Disease: MALDI Imaging of Formalin-fixed, Paraffin-embedded Human Hippocampal Tissue.

A method for the molecular mapping of formalin-fixed, paraffin-embedded human hippocampal tissue affected by Alzheimer's disease (AD) is presented. This approach utilizes imaging mass spectrometry (IMS) with matrix-assisted laser desorption/ionization (MALDI). The usefulness of this technique in comparing diseased versus nor mal tissue at the molecular level while continuing to maintain topological and morphological integrity is evident in the preliminary findings. The critical correlation of the deparaffination, washing, matrix deposition, and analysis steps in handling the tissue sections and how these steps impact the successful mapping of human hippocampal tissue is clearly demonstrated. By use of this technique we have been able to identify several differences between the hippocampal AD tissue and the control hippocampal tissue. From the observed peptide clip masses we present preliminary identifications of the amyloid-beta peptides known to be prominent in the brains of those with AD. We have obtained high-resolution mass spectra and mass images with 100µm spatial resolution. Future experiments will couple this work with MALDI LIFT experiments to enable top down proteomics of fresh frozen tissue, which is not possible with paraffin-embedded tissues.