Objective:To investigate the role of reactive astrocytes expressing aromatase(ARO)in the penumbra during ischemic stroke.Methods:A mouse model of middle cerebral artery occlusion(MCAO/R)was prepared using the suture method.Western blot and immunofluorescence staining were used to observe the expression of ARO in the penumbra after ischemia reperfusion.We generated a glial fibrillary acidic protein promoter-driven aromatase knock-out(GFAP-ARO-KO)mouse model in vivo.Neurologic impairment scores,rotarod test,grip strength test and adhesive removal test on the plantar surface of the paw were performed after MCAO/R modeling.Results:In wild type mice,the expression of ARO was significantly increased in astrocytes in the penumbra after MCAO/R(P<0.01).Compared to the control group,the expression of ARO in the GFAP-ARO-KO group was significantly reduced in astrocytes in the penumbra after MCAO/R.And loss of ARO increased cerebral infarction volume and aggravated sensorimotor impair-ment.Conclusion:After ischemic stroke,reactive astrocytes in the penumbra highly express ARO and play a protective role in post-ischemia reperfusion injury.

Objective:To observe the effects of electroacupuncture(EA)on learning and memory ability and nucle-ar factor E2 related factor 2(Nrf2),glutathione peroxidase 4(GPX4),NAD(P)H-quinone oxidoreductase 1(NQO1),reactive oxygen species(ROS)in hippocampus of neonatal rats with hypoxic-ischemic brain damage(HIBI)and its anti-oxidative stress mechanism.Methods:A total of 76 neonatal rats were randomly divided into Sham opera-tion group(Sham),HIBI model group(HIBI),electroacupuncture group(HIBI+EA),and Nrf2 inhibitor ML385 group(HIBI+EA+ML385).The neonatal rat model of HIBI was established by classical Rice method.The HIBI+EA group was treated with electroacupuncture for 30 min/d for 14 consecutive days.In the HIBI+EA+ML385 group,30 mg/kg ML385 was intraperitoneally injected at 1 h before each electroacupuncture intervention.Morris water maze test was performed on 21 days after modeling to test the learning and memory ability of neonatal rats in each group.Nissl staining and HE staining were used to observe the morphology of neurons in the hippocampal CA1 region,and DHE flu-orescent probe was used to detect the expression of ROS in the hippocampal CA1 region.The contents of Nrf2,GPX4 and NQO1 in hippocampus were detected by Western blot.Results:Compared with the Sham group,the HIBI group had severe pathological damage,a prolonged escape latency,a decreased number of platform crossings,a significantly increased expression of ROS,and a significantly decreased expression of Nrf2,GPX4,and NQO1(P<0.05).Com-pared with HIBI group,the pathological damage was significantly attenuated,the escape latency was shortened,the number of platform crossings was increased,the expression of ROS was decreased,and the expression of Nrf2,GPX4 and NQO1 was increased in HIBI+EA group(P<0.05).Compared with HIBI+EA group,the pathological damage was aggravated,the escape latency was prolonged,the number of crossing the platform was decreased,the expression of ROS was increased,and the expression of Nrf2,GPX4,and NQO1 was decreased in HIBI+EA+ML385 group(P<0.05).Conclusion:Electroacupuncture can effectively improve the learning and memory ability of hypoxic-ischemic neonatal rats,which is related to its effect in reducing oxidative stress in hippocampal neurons by regulating Nrf2 signa-ling pathway.

Objective:To explore the mechanism of Ginkgo biloba extract(EGb)on cerebral ischemia reperfusion injury(CIRI)in rats via the advanced glycation end products(AGEs)/receptor for AGEs(RAGE)pathway.Methods:SD rats were randomly divided into sham operation group(Sham group),CIRI group,CIRI+EGb pretreat-ment group(CIRI+EGb group),CIRI+AGEs inhibitor alagebrium chloride(ALT711)group(CIRI+ALT711 group)and CIRI+EGb+ALT711 group.HE,Nissl and Prussion blue staining were used to observe pathological chan-ges in the cerebral cortical area.The expression of AGEs,RAGE and nicotinamide adenine dinucleotide phosphate oxi-dase 4(NOX4)in the cerebral cortical area was detected by immunohistochemistry,the expression of AGEs,RAGE,NOX4,ferritin heavy chain 1(FTH),glutathione peroxidase 4(GPX4)and solute carrier family 7 member 11(SLC7A11)in the cerebral cortical area was detected by Western blot,and the expression of RAGE and NOX4 mRNA in the cerebral cortical area was detected by RT-qPCR.Results:Compared with the Sham group,the pathological dam-age in the brain tissue of rats in the CIRI group was observed;the expression of AGEs,RAGE and NOX4 was increased(P<0.01),the expression of FTH,GPX4 and SLC7A11 was reduced(P<0.01),the expression of RAGE and NOX4 mRNA was increased(P<0.01);compared with the CIRI group,the pathological damage in the brain tissue of rats in the CIRI+EGb group and CIRI+ALT711 group was reduced,the expression of AGEs,RAGE and NOX4 was reduced(P<0.01),the expression of FTH,GPX4 and SLC7A11 was increased(P<0.01),the expression of RAGE and NOX4 mRNA was reduced(P<0.05);compared with the CIRI+ALT711 group,the pathological damage in the brain tissue of rats,as well as the expression of AGEs,RAGE and NOX4 in the CIRI+EGb+ALT711 group were re-duced(P<0.01),the expression of FTH,GPX4 and SLC7A11 was increased(P<0.01),the expression of RAGE and NOX4 mRNA was reduced(P<0.01).Conclusion:EGb could protect CIRI by inhibiting NOX4 and ameliorating ferroptosis through the AGEs/RAGE pathway.

Objective:To study the effects of aluminum exposure on learning and memory and the expression of nerve growth factor(NGF)in the hippocampus of offspring rats,and to investigate the mechanism by which aluminum impairs learning and memory function.Methods:Forty pregnant Wistar rats were randomly assigned to the Control group(Control),low-dose Al group(Al-L),medium-dose Al group(Al-M)and high-dose Al group(Al-H).The off-spring rats were fed with Al through breast milk from birth to weaning,while the rats in the control group were fed with distilled water.The maternal rats Al-L,Al-M and Al-H groups drank distilled water solution containing 2.0,4.0 and 8.0 g/L AlCl3,respectively.After weaning,the offspring rats in the aluminum exposure group drank distilled water so-lution containing 2.0,4.0 and 8.0 g/L AlCl3 by themselves until the 90th day after birth to establish the offspring rat model of subchronic aluminum exposure.After aluminum exposure,the shuttle box test was used to detect the learning and memory ability of offspring rats,and the body weight of offspring rats and hippocampus were weighed to evaluate the effect of aluminum exposure.The expression of nerve growth factor(NGF)protein in hippocampus of offspring rats was detected by Western blot,and the expression of NGF mRNA in hippocampus of offspring rats was detected by real time RT-PCR.Results:The body weight of offspring rats in Al-H group was significantly lower than that in the other three dose groups.In the shuttle box test,compared with the control group,the active avoidance response and passive avoid-ance response of the offspring rats in the aluminum exposure group showed a downward trend with the increase of alumi-num exposure dose,indicating that the learning and memory ability of the offspring rats in the aluminum exposure group was impaired.Compared with the control group,the NGF protein content and NGF mRNA expression in the hippocam-pus of offspring rats in the aluminum exposure group were significantly decreased.Conclusion:Subchronic aluminum exposure down-regulates the expression of NGF in the hippocampus,which may cause learning and memory impairment in offspring rats.

Objective:To study the whole-brain distribution of vasoactive intestinal peptide(VIP)-positive neurons in the mouse brain and provide assistance for anatomical and functional studies of VIP neurons.Methods:VIP-Cre::Ai47 mice were used to label VIP neurons in the whole brain.Then,fluorescent imaging of the whole brain slices from VIP-Cre::Ai47 mice was calibrated using the standard brain map.Finally,the distribution density of VIP-positive neurons in different regions of the whole brain was statistically analyzed.Results:The overall distribution densities of VIP neurons in the cortex,olfactory bulb,and hippocampus were all greater than 5 neurons/mm2,and the distribution densities varied greatly in different subregions.The overall distribution density of VIP in the amygdala in the subcortical region was 4 neurons/mm2,and the distribution densities of VIP in the thalamus,hypothalamus,midbrain,and hind-brain regions were less than 2 neurons/mm2 on average,except for that in the supraoptic nucleus of the hypothalamus,where the density of VIP neuron distribution reached 20 neurons/mm2.Conclusion:VIP-positive neurons are mainly distributed in the cortex,hippocampus,and amygdala,which are highly associated with cognition and affection,and are rarely distributed in the thalamus and midbrain.These results suggest that VIP neurons play an essential role in emo-tional and cognitive functions.

Objective:To investigate the inhibitory effect and mechanism of puerarin(Pue)on hydrogen peroxide(H2 O2)induced ferroptosis in the rat Schwann cell derived cell line RSC96.Methods:The RSC96 cells were incuba-ted with H2 O2 to establish a cellular injury model,while a subset of cells were co-incubated with H2 O2 and Pue.The vi-ability of cells was examined using the CCK-8 assay.The intracellular levels of glutathione(GSH),total superoxide dismutase(T-SOD),reactive oxygen species(ROS),malondialdehyde(MDA),and ferrous ions(Fe2+)levels were quantified using commercial kits.Western blot was employed to detect the protein expression level of glutathione peroxi-dase 4(GPX4),cyclooxygenase-2(COX-2),solute carrier family 7 member 11(SLC7A11),nuclear factor erythroid 2-related factor 2(Nrf2),and heme oxygenase-1(HO-1).Immunofluorescence assay was performed to examine the expression and nuclear distribution of Nrf2.Results:Pue pretreatment significantly increased the survival rate of H2 O2-treated RSC96 cells,increased the intracellular content of GSH and T-SOD,and inhibited the concentration of ROS and MDA.It also activated the nuclear translocation of Nrf2 and upregulated GPX4,SLC7A11,HO-1,and Nrf2 proteins in RSC96 cells;This effect was abolished by the Nrf2 inhibitor ML385.Conclusion:Pue treatment alleviated the H2 O2-induced ferroptosis of RSC96 cells via the Nrf2/SLC7A11/GPX4 signaling pathway.

Objective:To establish a simple and efficient method for in vitro extraction,culture and identification of brain microvascular endothelial cells(BMECs)of rabbits.Method:The cerebral cortex of 3-week-old rabbits was cut up,sieved and digested with type II collagenase to obtain pure brain microvascular segments for primary culture and identification.Results:The cultured target cells grew in a typical"cobblestone-like"arrangement.Immunohistochemi-cal staining for von Willebrand factor(vWF)related antigen showed that the cytoplasm was presented as brownish red and the expression was positive.Conclusion:The physical sieving method combined with the chemical enzyme diges-tion method can simply and efficiently culture primary rabbit BMECs with strong activity and high purity.

Objective:To study the effects of epidermal growth factor(EGF)on the coordinated motor behaviors and changes of nigrostriatal dopaminergic system under the impact of EGF in middle-aged rats.Methods:Healthy aged Sprague Dawley(SD)rats were subcutaneously administered EGF(0.1 mg/ml)in the dorsal region for 7 days.Adhe-sive removal test,tapered beam walking test and descending a wire mesh pole test were performed to detect the changes in the coordinated motor behaviors of rats as well as changes in the expression of tyrosine hydroxylase(TH)and dopa-mine transporter(DAT)of nigrostriatal dopaminergic system in rats.Results:Middle-aged rats showed reduced behav-ioral parameters of adhesive removal test,tapered beam walking test and descending a wire mesh pole test compared with those of adult rats(P<0.05),which were improved after treatment with EGF(P<0.05).The expression of TH and DAT in nigrostriatal dopaminergic system was down-regulated in middle-aged rats compared with that in adult rats(P<0.01),however,which were up-regulated after treatment with EGF(P<0.01).Conclusion:EGF can amelio-rate the decline in coordinated motor behaviors and increases the activity of nigrostriatal dopaminergic system in middle-aged rats.

Objective:To explore the effects of essential tremor(ET)on the mitochondrial morphology of GABAer-gic and glutamatergic neurons in the inferior olive(IO).Methods:The ET mouse model was established via intraper-itoneal injection of harmaline.Twelve 8-week-old male C57BL/6J mice were randomly divided into saline control group and harmaline treatment group(HA).Behavioral tests,including open field test,rotarod test,balance beam test,and tremor scoring,were conducted to assess the behavior of mice.Using genetic engineering technology and the CRISPR/Cas9 system,we designed and generated 6 male GAD2-Mito-GFP mice and 6 male VGLUT2-Mito-GFP mice,all being 8-week-old.The mice of each transgenic line were randomly divided into Control and HA group.Immunofluorescence staining was used to analyze the expression of c-FOS positive cells in the IO of both the Control and HA groups,and to classify different types of neurons.Mitochondrial network analysis(MiNA)was performed to quantitatively analyze the area,mean aspect ratio,branch length,and other of mitochondria in different types of neurons in the IO under ET con-ditions.Results:Compared to the Control group,the HA group exhibited motor abnormalities and significant tremors.Immunofluorescence results showed a significant increase in the number of c-FOS positive cells in the IO,primarily in GABAergic neurons.MiNA results revealed that the mitochondria of GABAergic neurons showed increased area,branch length diameter,demonstrating irregular morphology.Conclusion:ET induces activation of GABAergic neurons in the IO and leads to more prominent mitochondrial morphological changes.This provides a new perspective for further inves-tigation of the pathogenesis of essential tremor and its relationship with mitochondrial.

Objective:This study investigated the dynamic expression of lipocalin-2(LCN2)and its receptor,brain-type organic cation transporter protein(BOCT),in spinal cords of hSOD1G93A transgenic mice during disease pro-gression,providing potential targets for early anti-inflammatory therapy for ALS.Methods:Utilizing hSOD1G93A trans-genic mice and their wild-type littermates(WT)as animal models,this investigation examined the expression of LCN2 and BOCT at four distinct disease stages:pre-symptomatic stage(60 d),early-symptomatic stage(95 d),symptomatic stage(108 d),and late-symptomatic stage(122 d).Spinal cords were harvested,then RT-qPCR,Western blot,and immunofluorescence double-labeling techniques were employed to assess alteration expressions of LCN2 and BOCT.Ad-ditionally,BV2 cells transfected with the pcDNA3.1-G93A-SOD1 overexpression plasmid served as an in vitro hSOD1G93A BV2 microglial model.After stimulated with LPS for 24 hours,LCN2 mRNA and protein expression in hSOD1G93A BV2 microglial cells and its culture medium were measured by RT-qPCR and ELISA respectively,while BOCT expression was measured by Western blot.Results:Compared with WT mice littermates,increased expression of LCN2 mRNA was detected in the spinal cords of hSOD1G93A transgenic mice at 108 and 122 d.No significant differences were observed in LCN2 or BOCT protein expression in the spinal cords of hSOD1G93A transgenic mice from 60 to 122 d.Double-immunofluorescence labeling revealed co-localization of LCN2 and BOCT with the microglial marker Iba-1 in the ventral horn of lumbar spinal cord of hSOD1G93A transgenic mice from 95 to 122 d.In hSOD1G93A BV2 microglial model,LPS stimulation led to a significantly increased LCN2 mRNA expression and protein secretion.Conversely,there was no significant change in BOCT protein expression after LPS stimulation.Conclusion:Our findings suggest that during ALS progression,there is an enhanced expression and release of LCN2 from activated microglia,potentially exacerbating neuroinflammation and neuronal degeneration.