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ObjectiveTo examine the inhibitory effects of berberine compounds， including columbamine， on acetylcholinesterase from the perspectives of drug-target binding affinity and kinetics and explore the blood-brain barrier （BBB） permeability of these compounds in different multi-component backgrounds. MethodThe median inhibitory concentration （IC50） of acetylcholinesterase by berberine compounds including columbamine was measured using the Ellman-modified spectrophotometric method. The binding kinetic parameters （Koff） of these compounds with acetylcholinesterase were determined using the enzyme activity recovery method. A qualitative analysis of the ability of these components to penetrate the BBB and arrive at the brain tissue in diverse multi-component backgrounds （including medicinal herbs and compound formulas） was conducted using ultra performance liquid chromatography-high resolution mass spectrometry （UPLC-HRMS）. ResultBerberine compounds， including columbamine， exhibited strong inhibition of acetylcholinesterase， with IC50 values in the nanomolar range. Moreover， they displayed better drug-target binding kinetics characteristics （with smaller Koff values） than the positive control of donepezil hydrochloride （P<0.01）， indicating a longer inhibition duration of acetylcholinesterase. Berberine components such as columbamine could penetrate the BBB to arrive at brain tissue in the form of a monomer， as well as in the multi-component backgrounds of Coptis and Phellodendri Chinensis Cortex medicinal extracts and the compound formula Huanglian Jiedutang. ConclusionThese berberine compounds such as columbamine exhibit a strong inhibitory effect on acetylcholinesterase and can arrive at brain tissue in multi-component backgrounds. In the level of pharmacological substance， this supports the clinical efficacy of compound Huanglian Jiedutang in improving Alzheimer's disease， providing data support for elucidating the pharmacological basis of compound Huanglian Jiedutang.
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Aim To investigate whether alisol A (AA) could improve the blood brain barrier (BBB) mediated cortex cerebral ischemia-repeifusion injury (CIRI) by inhibiting matrix metalloproteinase 9 (MMP-9). Methods The global cerebral ischemia- reperfusion (GCI/R) model in mice was established, and the AA was intragastric injected subsequently for seven days. The modified neurological severity scores (mNSS), open field test and Y-maze test were applied to detect neurological function. Magnetic resonance spectroscopy (MRS) was used to detect relevant neu- rosubstance metabolism in cortex of mice. Transmission electron microscope (TEM) was employed to observe the ultrastructure of BBB in cortex. Western blot and immunohistochemistry were used to detect the MMP-9 level in cortex. The binding possibility of A A and MMP-9 was determined by molecular docking. Results Compared with Sham group, mice in GCI/R group have an increased mNSS score but decreased at total distance and center distance to total distance ratio in open field test as well as alternation rate in Y-maze test (P<0.01). While mice in GCI/R + AA group have a decreased mNSS score but increased at total distance and center distance to total distance ratio in open field test as well as alternation rate in Y-maze test (P<0.01) compared with GCI/R group. MRS results found that in cortex of GCI/R group mice, the level of GABA and NAA significantly decreased while the Cho, mI and Tau level increased (P<0.01). Whereas in GCI/R + AA group mice, the GABA and NAA level increased and the Cho, ml and Tau decreased significantly (P<0.01). By TEM we observed that the basilemma of cerebral microvessels collapsed, the lumen narrowed, the endothelial cells were active and plasma membranes ruffled, gaps between cells were enlarged and tight junctions were damaged and the end feet of astrocytes were swollen in GCI/R group mice. While in GCI/R + AA group mice, the lumen was filled, plasma membranes of endothelial cells were smooth, tight junctions were complete and end feet of astrocytes were in normal condition. Western blot and immunohistochemistry both found that the MMP-9 level increased in GCI/R group mice (P < 0.01) and decreased in GCI/R + AA group mice (P < 0.05). Molecular docking proved the binding between aliso A and MMP9 through TYR-50 and ARG-106, and the binding energy was calculated as -6.24 kcal · mol
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Oligonucleotide drugs have experienced accelerated development in the past 10 years, and some of them have been used in clinical treatment. Because of its convenient design, flexible sequence, and high specificity, it is expected to solve the “undruggable” challenge of many targets which are difficult in drug development. Moreover, its clinical transformation period and cost are relatively low, which makes oligonucleotide drug become the frontier of emerging biotechnology drug discovery. Brain diseases include a series of incurable diseases, such as neurodegenerative diseases, glioma, and motor neuron diseases. Many of them are age-related and regarded as aging-associated brain diseases. Due to the complex etiology, many targets are difficult to be drugged. At the same time, the existence of the barrier system “blood-brain barrier” in the brain makes most drugs unable to achieve effective accumulation at brain lesions, and many small molecule drugs have failed in clinical transformation. The specificity and sequence flexibility of oligonucleotide acid drugs provide new possibilities for drug development, but they also face the challenge of brain delivery. Although a variety of oligonucleotide drugs have been used in the medical market, brain-targeted oligonucleotide drugs are still extremely rare. This article reviewed recent advances and discussed key topics and clinical transformation challenges in this field, such as clinical approval cases, bottlenecks of brain-targeted delivery and current strategies, as well as potential targets for aging-related brain diseases.
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Objective @#To ob serve the expression and trends of tight j unction proteins Occludin and zonula occluden-1 (ZO-1) in blood brain barrier (BBB) of rats with traumatic brain injury (TBI) , and to explore the intervention effect of cannabidiol (CBD) on the BBB . @*Methods @#The TBI model of rat was prepared by modified “Feeney free fall method ”and randomly divided into three groups : the sham operated group ( Sham group) , the model group (TBI + vehicle group) and the CBD intervention group ( TBI + CBD group) , with 24 rats in each group . Each group was subdivided into six time points : 8 h , 1 , 2 , 3 , 5 and 7 d after injury. The expression of Occludin and ZO-1 , which are closely related to the permeability of BBB , was detected by immunohistochemistry , immuno fluorescence staining and Western blot at different points . The permeability of BBB was detected by sodium fluores cein assay.@*Results @#The results of immunohistochemistry showed that compared with Sham group , the positive ex pression of Occludin and ZO-1 decreased with time after brain trauma ( P < 0.05) , and both reached the lowest level at 2 d . The expression levels of Occludin and ZO-1 were up regulated after 1 d of CBD intervention ( P < 0.05) . Immunofluorescence staining showed a similar trend to Western blot results , with Occludin and ZO-1 fluo rescence expression intensity and protein expression reduced after TBI compared with Sham group ( P < 0.05 ) . And the expression levels of Occludin and ZO-1 were up regulated after 2 d of CBD intervention (P < 0.05) . The results of fluorescein sodium experiment showed that the BBB integrity of brain tissue was destroyed after TBI , and the permeability increased after TBI (P < 0.01) . The permeability of BBB decreased after CBD intervention (P < 0.05) . @*Conclusion @#The expression of tight junction proteins O ccludin and ZO-1 decreases after TBI , and the permeability of BBB is disrupted , and CBD intervention reverses the disruption of the BBB by TBI .
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Cognitive impairment is a common clinical complication in type 2 diabetes (T2DM). T2DM-related cognitive impairment has complex and multifactorial pathogenesis. Cerebral microvascular dysfunction is an important pathological change in patients with T2DM and pre-T2DM, and it can induce blood-brain barrier injury and impaired blood perfusion regulation, with disturbed neurovascular coupling and cerebral autoregulation, leading cognitive impairment. This article reviews the epidemiology and pathophysiological mechanisms related to T2DM cerebral microvascular lesions and cognitive impairment, and how to monitor changes of cerebral microvascular structure and function so as to provide new approach for diagnosis and treatment of T2DM-related cognitive impairment.
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Cell membrane-modified nanoparticles (NPs) have attracted widespread attention as a new approach for malignant brain tumors in recent years. This method can enhance the targeting, biocompatibility, and circulation time of NPs by preserving the characteristics of source cell membrane, thereby ensuring efficient drug delivery to intracranial lesions. This paper focuses on the research progress in this field, especially advantages of NPs penetrating the blood-brain barrier, immune evasion and drug delivery, as well as modified effect of different cell membrane on NPs, in order to provide help for treatment of malignant brain tumors.
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SUMMARY OBJECTIVE: Blood-brain barrier is a protective layer that regulates the influx and efflux of biological materials for cerebral tissue. The aim of this study was to investigate the effects of Biochanin A on cerebral histopathology and blood-brain barrier immunohistochemically. METHODS: A total of 24 rats were assigned to three groups: sham, ischemia-reperfusion, and ischemia-reperfusion+Biochanin A. Ischemia-reperfusion was performed by occluding the left carotid artery for 2/24 h. Notably, 20 mg/kg Biochanin A was administered to rats for 7 days after ischemia-reperfusion. Blood was collected for malondialdehyde and total oxidant/antioxidant status analysis. Cerebral tissues were processed for histopathology and further for immunohistochemical analysis. RESULTS: Malondialdehyde content with total oxidant status value was significantly increased and total antioxidant status values were significantly decreased in the ischemia-reperfusion group compared with the sham group. Biochanin A treatment significantly improved scores in the ischemia-reperfusion+Biochanin A group. The normal histological appearance was recorded in the cerebral sections of the sham group. Degenerated neurons and vascular structures with disrupted integrity of the cerebral cortex were observed after ischemia-reperfusion. Biochanin A alleviated the histopathology in the cerebrum in the ischemia-reperfusion+Biochanin A group. Ischemia-reperfusion injury decreased the expression of blood-brain barrier in the ischemia-reperfusion group compared to the sham group. Administration of Biochanin A upregulated the blood-brain barrier immunoreactivity in the cerebrum by restoring blood-brain barrier. CONCLUSION: Cerebral ischemia-reperfusion caused an increase in oxidative stress and pathological lesions in the cerebrum. Biochanin A treatment restored the adverse effects of ischemia-reperfusion injury by restoring blood-brain barrier.
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Objective:To evaluate the role of aquaporin 4 (AQP4) in dexmedetomidine-induced reduction of blood-brain barrier permeability in mechanically ventilated mice and the relationship with protein kinase C (PKC).Methods:One hundred and fifty clean-grade healthy male C57BL6 mice, weighing 20-25 g, aged 8-12 weeks, were divided into 5 groups ( n=30 each) using a random number table method: control group (group C), mechanical ventilation group (group V), LY317615 group (group L), dexmedetomidine group (group D), and dexmedetomidine+ PMA group (group DP). Group C spontaneously breathed air for 6 h. The animals were mechanically ventilated for 6 h in group V. PKC inhibitor LY3176 15 μg/kg was intraperitoneally injected at 30 min before mechanical ventilation in group L. Dexmedetomidine 50 μg/kg was intraperitoneally injected at 30 min before mechanical ventilation in D and DP groups. PKC activator PMA 15 μg/kg was intraperitoneally injected at 60 min before mechanical ventilation in group DP. Mice were anesthetized at 1 day after mechanical ventilation, then sacrificed and hippocampal tissues were taken for microscopic examination of pathological changes in the hippocampal CA1 and CA3 areas (with a light microscope). Brain tissues were also taken to measure the water content and content of Evans blue (EB) and to detect the expression of PKC and AQP4 (by Western blot). The cognitive function was evaluated using a novel object recognition task at 3 days after mechanical ventilation. Results:Compared with group C, the water content and EB content of brain tissues were significantly increased after mechanical ventilation, the expression of PKC and AQP4 in brain tissues was up-regulated, the percentage of novel object exploration and discrimination index were decreased ( P<0.05), and the histopathological damage in the hippocampal CA1 and CA3 areas was aggravated in group V and group DP. Compared with group V, the water content and EB content of brain tissues were significantly decreased after mechanical ventilation, the expression of PKC and AQP4 in brain tissues was down-regulated, the percentage of novel object exploration and discrimination index were increased ( P<0.05), and the histopathological damage in the hippocampal CA1 and CA3 areas was significantly attenuated in group D and group L. Compared with group D, the water content and EB content of brain tissues were significantly increased after mechanical ventilation, the expression of PKC and AQP4 in brain tissues was up-regulated, the percentage of novel object exploration and discrimination index were decreased ( P<0.05), and the histopathological damage in the hippocampal CA1 and CA3 areas was aggravated in group DP. Conclusions:AQP4 is involved in dexmedetomidine-induced reduction of blood-brain barrier permeability in mechanically ventilated mice, and the mechanism is related to inhibiting activation of PKC.
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Objective To analyze the effect of LncRNA MEG3 on the blood-brain barrier in neonatal mice with hypoxic-ischemic brain injury(HIBD)by regulating miR-17-5p.Methods A total of 90 C57BL mice were randomly grouped into control group,model group,si-NC group,si-LncRNA MEG3 group,si-LncRNA MEG3+anti-miR-NC group and si-LncRNA MEG3+anti-miR-17-5p group,with 15 mice in each group.Except for the control group,the rest of the mice were constructed with HIBD model,and the Longa score was used to evaluate the nerve damage of mice.The ultrastructure of vascular endothelial cells around brain tissue was observed by electron microscope.The permeability of blood-brain barrier in mice was measured by EB method.The levels of LncRNA MEG3 and miR-17-5p in the brain tissue of mice in each group were determined by qRT-PCR.The levels of ZO-1 and Occludin protein in the brain tissue of mice were determined by Western blotting.Results Compared with control group,the vascular endothelium of mice in model group was unevenly thin and thick,and showed edema in many places.Compared with model group,the vascular endothelial cells in the si-LncRNA MEG3 group were gradually tightly connected,the thickness was more uniform,and the edema was reduced.Compared with the si-LncRNA MEG3 group,vascular endothelial cell damage was intensified in the si-LncRNA MEG3+anti-miR-17-5p group.Compared with those in the control group,the neurological deficit score,brain water content,EB content,and LncRNA MEG 3 level in the model group were significantly increased,miR-1 7-5 p level,ZO-1 and Occludin expression were significantly decreased(all P＜0.05).Compared with those in model group,there were no significant differences in neural function deficit score,brain water content,EB content,lncRNA MEG3 level,miR-17-5p level,ZO-1 and Occludin expression in si-NC group(all P＞0.05);the neurological deficit score,brain water content,EB content and LncRNA MEG3 level in si-LncRNA MEG3 group were significantly decreased,miR-17-5p level,ZO-1,and Occludin expression were significantly increased(all P＜0.05).Compared with those in si-LncRNA MEG3 group,there were no significant differences in neural function deficit score,brain water content,EB content,LncRNA MEG3 level,miR-17-5p level,ZO-1 and Occludin expression in si-LncRNA MEG3+anti-miR-NC group(all P＞0.05);the neurological deficit score,brain water content and EB content in si-LncRNA MEG3+anti-miR-17-5p group were significantly increased,miR-17-5p level,ZO-1 and Occludin expression were significantly decreased(all P＜0.05).Conclusion LncRNA MEG3 silencing may reduce the permeability of the blood-brain barrier in neonatal mice with HIBD by up-regulating miR-17-5p,maintaining the protective effect of the blood-brain barrier on the brain,and protecting brain tissue.
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Objective:To investigate the protective mechanism of TRPV4 channel inhibitor on blood-brain barrier(BBB)damage after traumatic brain injury(TBI).Methods:The TBI rat model was established.TRPV4 channel inhibitor HC067047 or PKC-δ inhibitor Rottlerin was used to detect changes in BBB permeability,neurological function score,and the expression of microvascular endothelial tight junction proteins ZO-1 and ZO-2 in brain injury areas after TBI.Results:Compared with the Sham group,BBB permeability significantly increased,brain neurological function score significantly decreased,and the expression of ZO-1 and ZO-2 significantly decreased in TBI group(P＜0.05).Compared with the TBI group,after administration of HC067047 or Rottlerin,changes in BBB permeability,brain neurological function score,the expression of ZO-1 and ZO-2 were partially reversed(P＜0.05).Conclusions:TBI-induced BBB injury may be mediated by TRPV4 channel regulating PKC-δ signaling pathway to affect the expression of tight junction proteins ZO-1 and ZO-2.Inhibition of TRPV4 channel function or PKC-δ signal molecule can partially alleviate BBB damage induced by TBI.This study may provide new ideas for the treatment of clinical TBI.
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Objective To explore the optimal duration of long-term mild hypothermia(MHT)for traumatic brain injury(TBI)in rats,and observe its effect on intracranial pressure(ICP)and neurological function.Methods Forty-eight healthy adult male SD rats were divided into the normal temperature treatment(NT)group,the MHT4 h group,the MHT24 h group and the MHT48 h group by random number table method,with twelve rats in each group.The TBI model of rats was prepared by electronic controllable cortical injury device,and ICP monitoring probe was implanted.After modeling,the NT group was treated with normal temperature(37℃),and the other groups were treated with low temperature(33.0±1.0)℃for 4 h,24 h and 48 h,respectively.ICP was monitored and brain water content(BWC)was calculated after MHT treatment in each group.Blood-brain barrier permeability was determined by Evansland(EB)staining.The expression of 5-bromodeoxyuracil nucleoside(BrdU),neuronal nuclear antigen antibody(NeuN)and leukocyte differentiation antigen 86(CD86)positive cells were detected by immunofluorescence staining.The expressions of B-cell lymphoma-2(Bcl-2),Bcl-2 associated X protein(Bax),inducable nitric oxide synthase(iNOS),interleukin(IL)-10 and arginase 1(Arg-1)were detected by Western blot assay.Results Compared with the NT group,levels of BWC,ICP,EB,and CD86 positive cells,Bax and iNOS expression levels were decreased in the MHT4 h group,the MHT24 h group and the MHT48 h group,and the number of BrdU positive cells and BrdU/NeuN double-labeled positive cells were increased in hippocampus.The expression levels of Bcl-2,IL-10 and Arg-1 were increased(P＜0.01).Compared with the MHT24 h group,levels of BWC,ICP and EB,and CD86 positive cells,Bax and iNOS expression were decreased,and the number of BrdU positive cells and BrdU/NeuN double-labeled positive cells were increased in the MHT48 h group,while levels of Bcl-2,IL-10 and Arg-1 expression were increased(P＜0.01).Conclusion Long-term MHT can promote the proliferation and differentiation of neurons,inhibit apoptosis and reduce inflammation by suppressing ICP rebound,further promoting neuroprotection after TBI.
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Currently,methamphetamine(MA)has become the most commonly abused synthetic stimulant.The long-term use of MA has resulted in serious mental disorders and cognitive impairments,posing significant public health and social issues both domestically and internationally.As a novel adjunctive therapy,exercise intervention can effectively mitigate the neuro-structural and functional injury caused by MA by suppressing neural oxidative stress,reducing inflammatory factors and cellular apoptosis levels,restoring glutamate/gamma-aminobutyric acid homeostasis and blood-brain barrier function,and promoting neuroplasticity.Exercise intervention also contributes to decreasing drug cravings,enhancing physical fitness,alleviating with-drawal symptoms,and reducing negative subjective emotions among addicts.Therefore,scientifically tailored exercise interven-tion programs with abundant types of sports and personalized exercise programs designed based on the physical and mental conditions of individuals with addiction can lead to better intervention outcomes and reduce the risk of relapse.This paper provides a comprehensive review of the research progress on the effects,mechanisms and intervention strategies of exercise on neural injury in MA addicts,aiming to provide evidence for the application of exercise intervention in drug withdrawal programs for MA addicts.
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Objective To study the effect of dual-mediated brain targeting liposomes(RVGPR9-SSL)as delivery vehicles on the blood brain barrier(BBB)permeability of doxorubicin(DOX),providing a new strategy for brain drug delivery.Methods The dual-mediated brain targeting liposomes(RVGPR9-SSL)were prepared by thin film dispersion/leading compound method.And the chemo-therapeutic drug DOX was encapsulated in RVGPR9-SSL(DOX@RVGPR9-SSL).Brain microvascular endothelial cells(BMVEC)were cultured and used to construct in vitro BBB models.The BBB model was then evaluated by a 4h leakage test,transmembrane resist-ance value(TEER)measurement,and tight junctions between cells observed by scanning transmission electron microscope(SEM).After the successful construction of the BBB model,the integrity of RVGPR9-SSL after crossing the BBB was investigated by confocal laser scanning microscopy using fluorescence a resonance energy transfer(FRET)pair.The effect of RVGPR9-SSL administration on BBB in-tegrity was evaluated by comparative analysis of BBB morphology and TEER values before and after liposome administration.The BBB per-meability of DOX@RVGPR9-SSL was investigated by fluorescence spectrophotometry.Results The encapsulation efficiency of DOX@RVGPR9-SSL was 97.25％.The TEER values of the constructed BBB model were all greater than 200Ω·cm2,and it was observed by SEM that the BMVEC cells were closely arranged and there were obvious tight junctions,indicating that the in vitro BBB model was suc-cessfully established and could be used for the investigation of BBB permeability.The 4h BBB cumulative permeability of DOX@RVGPR9-SSL was greater than 10％,which was significantly higher than that of free DOX.And both BBB and liposomes maintained good integrity after administration.Conclusion RVGPR9-SSL can significantly improve the BBB permeability of DOX,indicating that it is a very promising brain drug delivery vehicle.
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Objective To investigate the protective effect and mechanism of propofol on the blood-brain barrier in rats with cerebral ischemia.Methods A total of 48 10-week-old male SD rats were randomly divided into the sham group,the cerebral ischemia group,the propofol group and the propofol+LY294002 group.Twenty-four hours before the induction of the model,the rats in the propofol+LY294002 group were intracerebroventricularly injected with PI3K inhibitor LY294002(0.3 mg·kg-1),and the rats in the other groups were administrated with saline(10 μL).Rats in the cerebral ischemia group,the propofol group and the propofol+LY294002 group established cerebral ischemia models by carotid artery occlusion.Rats in the sham group only isolated the common carotid artery and ligated the external carotid artery without other treatment.During the modeling period,the rats in the propofol group and the propofol+LY294002 group were given propofol(10 mg·kg-1)via the tail vein,and the sham group and the propofol group were treated with saline.After 24 hours,the neurological function of rats was evaluated by Zea Longa method;the area of cerebral infarction was detected by TTC staining;the degree of cerebral edema was detected by the dry-wet weight method.EB tracer method was used to evaluate the integrity of the blood-brain barrier;ELISA was used to detect inflammatory cytokines in cerebrospinal fluid;Western blot was used to detect the expression of PI3K/AKT signaling pathway proteins and blood-brain barrier tight junction proteins Claudin-5 and Occludin.Results Cerebral ischemia led to the increase of neurological function scores and local infarction of brain tissues in rats.Compared with the sham group,the EB content in the brain tissue of rats in the cerebral ischemia group increased,the degree of brain edema increased,and the content of inflammatory cytokines in the cerebrospinal fluid increased.And the use of propofol could significantly decrease the neurological function scores,reduce the area of cerebral infarction,inhibit EB penetrating blood-brain barrier,reduce the degree of brain edema,reduce the release of inflammatory cytokines,and up-regulate the expression of PI3K/AKT signaling pathway proteins and tight junction proteins Claudin-5 and Occludin.LY294002 significantly reversed the above effects of propofol.Conclusion Propofol can maintain the expression of tight junction proteins Claudin-5 and Occludin through the PI3K/AKT signaling pathway,protect the structural and functional integrity of blood-brain barrier,reduce the degree of brain edema,prevent other inflammatory cytokines into the brain tissue,reduce cerebral infarction,and alleviate the neurological functional damage caused by cerebral ischemia.
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Objective To analyze the bioelectromagnetic dose of human blood-brain barrier opening induced by electromagnetic pulse.Methods A typical exposure platform was used to establish an environment for human brain dosimetric study.The bioelectromagnetic dose was evaluated with electromagnetic simulation method using a 3D digital human model.Results The electric field at the centre of the head reached a peak of 1.49 kV/m,and there was a decrease of 41.6 dB from the excitation field.The maximum electric field amplitude on the surface of the nose tip was 1795 kV/m.The head had an average absorption rate of 4.16×10-8 J/kg under one pulse,while under extreme conditions with a repetition frequency of 1000 s-1,the average specific absorption rate of the head was 4.16×10-5 W/kg.Conclusion Local high-intensity electric fields pose significant safety risks in clinical application,and it is necessary to study the means of inhibiting local high-intensity electric field in combination with the dose-effect relationship of blood-brain barrier opening.The human brain bioelectromagnetic doses provided by the study can be used to evaluate the clinical efficacy.
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Objective To observe the effects of Xixin Decoction on the blood-brain barrier permeability and the expressions of P-glycoprotein(P-gp),cannabinoid receptor 1(CB1)and cannabinoid receptor 2(CB2)in hippocampal tissue of rapidly aging mice(SAMP8);To explore the possible mechanism of Xixin Decoction in the treatment of Alzheimer disease(AD).Methods Totally 60 SAMP8 mice were randomly divided into model group,probiotics group,and Xixin Decoction high-,medium-and low-dosage groups,with 12 mice in each group,another 12 SAMR1 mice were set as control group.The medicated groups received corresponding drugs by gavage for 10 weeks respectively,while the control group and model group were gavaged with equal volume of distilled water.Morris water maze test was used to detect the learning and memory ability of mice,the blood-brain barrier permeability was detected by Evans blue method,the contents of matrix metalloproteinase 9(MMP9),nuclear factor(NF)-κB and tumor necrosis factor-α(TNF-α)in serum were determined by ELISA,the expressions of P-gp,CB1 and CB2 in hippocampal tissue were detected by Western blot,P-gp expression in hippocampal tissue was detected by immunofluorescence staining.Results Compared with the control group,the learning and memory ability of mice in model group significantly decreased,Evans blue exudation in brain tissue significantly increased,the contents of MMP9,TNF-α and NF-κB in serum significantly increased,the expressions of P-gp and CB2 protein significantly decreased,the expression of CB1 protein significantly increased,with statistical significance(P<0.01,P<0.05).Compared with the model group,the learning and memory ability of mice in Xixin Decoction high-dosage group significantly increased,the Evans blue exudation in brain tissue significantly decreased,the contents of MMP9,TNF-α and NF-κB in serum significantly decreased,the protein expressions of P-gp and CB2 significantly increased,and the protein expression of CB1 significantly decreased,with statistical significance(P<0.01,P<0.05).Conclusion Xixin Decoction can improve the spatial learning and memory ability of AD model mice,and its mechanism is related to regulating the permeability of the blood-brain barrier and related protein expression,and inhibiting neuroinflammation.
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Objective To investigate the role and underlying mechanism of atorvastatin on hyper-glycemia induced hemorrhagic transformation(HT)in a mouse model of cerebral ischemia.Meth-ods A total of 36 SPF-grade male C57BL/6 mice were randomly divided into sham operation group,HT model group and atorvastatin group,with 12 mice in each group.HE staining was used to observe cerebral hemorrhage,immunofluorescent staining was employed to detect the integrity of blood-brain barrier,and Western blotting was applied to measure the protein expression of IgG,ZO-1,occludin,claduin5,MMP-2 and-9 in ischemic penumbra brain tissues.Results Com-pared with sham operation group,the neurological deficit score,mortality rate,HT incidence,HT grading score,IgG fluorescence intensity,and protein levels of IgG,MMP-2 and-9 were signifi-cantly increased,while the protein levels of ZO-1,occludin and claudin5 were obviously decreased in the HT model group(P＜0.01).Atorvastatin treatment resulted in significantly lower neuro-logical deficit score(2.73±1.19 vs 3.91±0.94),mortality rate(16.7％vs 41.6％),HT incidence(58.3％vs 91.6％),HT grading score(1.00±1.04 vs 2.58±1.13),IgG fluorescence intensity(504.30±105.52 a.u vs 859.91±153.28 a.u),and protein levels of IgG(4.55±1.40 vs 12.06± 3.73),MMP-2(1.87±0.41 vs 2.95±0.68)and-9(1.47±0.24 vs 2.12±0.23)(P＜0.05,P＜0.01),and increased protein levels of ZO-1(1.55±0.20 vs 0.53±0.10),occludin(0.92±0.11 vs 0.35±0.07)and claudin5(0.58±0.04 vs 0.30±0.05)(P＜0.01)when compared with the HT model group.Conclusion Atorvastatin can reduce the permeability of blood-brain barrier by in-hibiting the activation of MMP-2 and MMP-9 and up-regulating the protein levels of ZO-1,occlu-din and claudin5,and thus attenuate hyperglycemia-induced HT.
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Objective To investigate the action mechanism of long non-coding RNA(lncRNA)-N1LR on blood-brain barrier(BBB)after cerebral ischemia-reperfusion(I/R)injury.Methods Primary rat brain microvascular endothelial cells(BMECs)were cultured and treated with OGD/R to simulate cerebral I/R injury.The experiment was divided into normal control group,ln-cRNA-N1LR OGD group,overexpression group(lncRNA-N1LR overexpression after OGD treat-ment)and silence group(lncRNA-N1LR silence after OGD treatment).The mRNA levels of ln-cRNA-N1LR,claudin-5 and occludin in each group were detected by RT-qPCR.The BBB permea-bility was detected by FITC-dextran infiltration assay.The expression of claudin-5 and occludin were detected by Western blotting.Results The mRNA levels of lncRNA-N1LR,occludin and claudin-5 were significantly decreased(0.31±0.01 vs 1.00±0.10,0.42±0.03 vs 1.01±0.13,0.38±0.03 vs 1.00±0.15,P＜0.05),and the BBB permeability was significantly increased(58.79± 3.04 vs 8.87±0.63,P＜0.05)in the OGD group than the control group.The lncRNA-N1LR over-expression group increased the mRNA expression of lncRNA-N1LR,occludin and claudin-5(0.67±0.07 vs 0.31±0.01,0.92±0.02 vs 0.42±0.03,0.70±0.08 vs 0.38±0.03,P＜0.05),and decreased the BBB permeability(41.57±2.43 vs 58.79±3.04,P＜0.05)than the OGD group.lncRNA-N1LR silence resulted in lower mRNA levels of lncRNA-N1LR,occludin and claudin-5(0.21±0.02 vs 0.31±0.01,0.31±0.03 vs 0.42±0.03,0.22±0.02 vs 0.38±0.03,P＜0.05),and enhanced BBB permeability(72.34±1.43 vs 58.79±3.04,P＜0.05)when compared with the OGD group.Conclusion Up-regulation of lncRNA-N1LR may play a neuroprotective role by reducing BBB permeability.
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The establishment of the cerebral pharmacokinetic model aims to truly reflect the disposition and course of action of drugs entering brain tissues, to ensure that brain-targeted drugs reach effective intracerebral concentrations, while preventing neurological damage from non-brain-targeted drugs, and to greatly improve effectiveness and safety. With the rapid development of research strategies and analytical techniques in the field of pharmacokinetics, intracerebral pharmacokinetic techniques have evolved from traditional brain tissue homogenization and cerebrospinal fluid extraction to in situ in vivo analysis techniques, from invasive techniques to non-invasive imaging techniques, and from the macroscopic tissue level to the microscopic cellular/subcellular level. A variety of pharmacokinetic research methods in brain are complementing each other and becoming increasingly perfect, gradually forming a comprehensive " subcellular-cellular-tissue" pharmacokinetic research system in brain, laying the foundation for elucidating the dynamic changes of drugs in brain and predicting the course of action of drugs in brain. This paper reviews the evolution and development of pharmacokinetic research strategies in brain, evaluates the advantages and limitations of various techniques and methods, and provides a reference for predicting the pharmacodynamic and toxic effects of drugs in brain tissues.
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Aim To investigate the effect of astaxanthin (ASTA) on the blood brain barrier (BBB) injury and cognitive disorders in mice induced by hyperglycemia and the possible mechanism. Methods db/db mice aged eight weeks were administered ASTA (5, 10, 20 mg • kg