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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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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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Objective To investigate the effect of plateau hypoxia on the blood-brain barrier after subarachnoid hemorrhage (SAH) in rats. Methods Adult male SD rats (n = 78) were randomly divided into 4 groups: sham group (sham), SAH model group (SAH), plateau hypoxia sham group (Hp sham) and plateau hypoxia SAH model group (Hp SAH). The rat model of plateau hypoxia was established through low-pressure simulation chamber (altitude 5000 m), and the SAH model was established by endovascular perforation method. At 24 hours after SAH, neurobehavior score and SAH grade were assessed. The morphological changes of neurons and apoptosis of nerve cells in the CA1 region of hippocampal were observed by the staining of Nissl and TUNEL. The expression of phosphorylated PI3K (p-PI3K), PI3K, phosphorylated Akt (p-Akt), Akt, phosphorylated nuclear factor κB (p-NF-κB), NF-κB, matrix metalloproteinase-9 (MMP-9), occludin and claudin-5 in hippocampal were detected by the method of Western blotting. The expression of occludin and claudin-5 proteins in the CA1 region of hippocampal were observed by immunofluorescent staining. Results At 24 hours after SAH, the neurobehavior score decreased significantly and SAH grade increased significantly in the SAH and Hp SAH group (P< 0.05). Neurobehavior score decreased significantly in the Hp SAH group compared with the SAH group (P < 0.05). In the SAH group, neurons in the CA1 region of hippocampus were atrophied and deformed, the arrangement were disordered, the number of neurons decreased significantly, and the apoptosis of nerve cells increased significantly(P< 0.05). Plateau hypoxia could aggravate the morphological damage of neurons and apoptosis of nerve cells. The expression of p-PI3K/PI3K, p-Akt/Akt, occludin and claudin-5 proteins decreased significantly, while the expression of p-NF-κB/NF-κB and MMP-9 proteins increased significantly in the SAH and Hp SAH group (P< 0.05). The expression of p-PI3K/PI3K and MMP-9 proteins increased significantly in Hp SAH group compared with the SAH group. The expression of claudin-5 protein increased significantly in Hp sham group compared with the sham group (P < 0.05). Immunofluorescent staining showed that the expression of occludin and claudin-5 proteins in the CA1 region of hippocampus decreased in the SAH group. Plateau hypoxia could further decreased the expression of occludin and claudin-5 proteins. Conclusion Plateau hypoxia aggravates blood-brain barrier disruption after subarachnoid hemorrhage in rats through inhibiting PI3K/Akt/NF-κB pathway.
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AIM: To investigate the effects of hyperoside on traumatic brain injury (TBI) rats by regulating the Ras homolog gene family, member A (RhoA)/Rho-associated coiled coil-forming kinase (ROCK) signal pathway. METHODS: The TBI rat model was established by modified Feeney free fall hit method, and was randomly divided into model group, low-dose hyperoside (60 mg / kg) group, high-dose hyperoside (120 mg / kg) group, high-dose hyperoside (120 mg / kg) + no load group, and high-dose hyperoside (120 mg / kg) + RhoA overexpression group, with 10 rats in each group, another 10 healthy rats were set as sham operation group, after hyperoside and plasmid were grouped, the nerve injury was detected by modified neurological deficit score (mNSS) and dark avoidance test; Evans blue (EB) quantitative method was used to detect the permeability of blood brain barrier in rats; ultrastructural damage of blood-brain barrier was observed by transmission electron microscopy; the levels of tumor necrosis factor- α (TNF- α), interleukin-8 (IL-8), superoxide dismutase (SOD) and malondialdehyde (MDA) in serum and brain tissue of rats were measured with the kit; and the expression of RhoA/ROCK pathway related proteins in rat brain was detected by Western blot. RESULTS: Compared with the sham operation group, the blood brain barrier structure of the model group rats was damaged, the step-through latency and SOD level decreased obviously (P0.05). CONCLUSION: Hyperoside can inhibit neuroinflammation and oxidative stress in TBI rats by down-regulating RhoA / ROCK signal pathway, thereby reducing the damage of blood brain barrier and repairing its neural function.
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Aim To develop a ultra-high performance liquid chromatography electrospray-ionization tandem mass spectrometry ( UPLC-MS/MS ) method for the simultaneous determination of salidroside derivative pOBz in rat plasma and brain tissue, and to study the pharmacokinetic profile and penetration of the blood-brain barrier in rats after a single dose intravenous administration of pOBz. Methods SD rats were administered pOBz at a dose of 50 mg • kg
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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
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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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The blood-brain barrier (BBB) impairment plays a crucial role in the pathological processes of aging-accompanied neurological diseases (AAND). Meanwhile, circadian rhythms disruption and gut microbiota dysbiosis are associated with increased morbidity of neurological diseases in the accelerated aging population. Importantly, circadian rhythms disruption and gut microbiota dysbiosis are also known to induce the generation of toxic metabolites and pro-inflammatory cytokines, resulting in disruption of BBB integrity. Collectively, this provides a new perspective for exploring the relationship among circadian rhythms, gut microbes, and the BBB in aging-accompanied neurological diseases. In this review, we focus on recent advances in the interplay between circadian rhythm disturbances and gut microbiota dysbiosis, and their potential roles in the BBB disruption that occurs in AAND. Based on existing literature, we discuss and propose potential mechanisms underlying BBB damage induced by dysregulated circadian rhythms and gut microbiota, which would serve as the basis for developing potential interventions to protect the BBB in the aging population through targeting the BBB by exploiting its links with gut microbiota and circadian rhythms for treating AAND.
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In recent years, growing awareness of the role of oxidative stress in brain health has prompted antioxidants, especially dietary antioxidants, to receive growing attention as possible treatments strategies for patients with neurodegenerative diseases (NDs). The most widely studied dietary antioxidants include active substances such as vitamins, carotenoids, flavonoids and polyphenols. Dietary antioxidants are found in usually consumed foods such as fresh fruits, vegetables, nuts and oils and are gaining popularity due to recently growing awareness of their potential for preventive and protective agents against NDs, as well as their abundant natural sources, generally non-toxic nature, and ease of long-term consumption. This review article examines the role of oxidative stress in the development of NDs, explores the 'two-sidedness' of the blood-brain barrier (BBB) as a protective barrier to the nervous system and an impeding barrier to the use of antioxidants as drug medicinal products and/or dietary antioxidants supplements for prevention and therapy and reviews the BBB permeability of common dietary antioxidant suplements and their potential efficacy in the prevention and treatment of NDs. Finally, current challenges and future directions for the prevention and treatment of NDs using dietary antioxidants are discussed, and useful information on the prevention and treatment of NDs is provided.
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Glioblastoma (GBM) is the most aggressive malignant brain tumor and has a high mortality rate. Photodynamic therapy (PDT) has emerged as a promising approach for the treatment of malignant brain tumors. However, the use of PDT for the treatment of GBM has been limited by its low blood‒brain barrier (BBB) permeability and lack of cancer-targeting ability. Herein, brain endothelial cell-derived extracellular vesicles (bEVs) were used as a biocompatible nanoplatform to transport photosensitizers into brain tumors across the BBB. To enhance PDT efficacy, the photosensitizer chlorin e6 (Ce6) was linked to mitochondria-targeting triphenylphosphonium (TPP) and entrapped into bEVs. TPP-conjugated Ce6 (TPP-Ce6) selectively accumulated in the mitochondria, which rendered brain tumor cells more susceptible to reactive oxygen species-induced apoptosis under light irradiation. Moreover, the encapsulation of TPP-Ce6 into bEVs markedly improved the aqueous stability and cellular internalization of TPP-Ce6, leading to significantly enhanced PDT efficacy in U87MG GBM cells. An in vivo biodistribution study using orthotopic GBM-xenografted mice showed that bEVs containing TPP-Ce6 [bEV(TPP-Ce6)] substantially accumulated in brain tumors after BBB penetration via transferrin receptor-mediated transcytosis. As such, bEV(TPP-Ce6)-mediated PDT considerably inhibited the growth of GBM without causing adverse systemic toxicity, suggesting that mitochondria are an effective target for photodynamic GBM therapy.
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The incidence rate of anxiety and depression is significantly higher in patients with inflammatory bowel diseases (IBD) than in the general population. The mechanisms underlying dextran sulfate sodium (DSS)-induced depressive-like behaviors are still unclear. We clarified that IBD mice induced by repeated administration of DSS presented depressive-like behaviors. The paraventricular thalamic nucleus (PVT) was regarded as the activated brain region by the number of c-fos-labeled neurons. RNA-sequencing analysis showed that lipocalin 2 (Lcn2) was upregulated in the PVT of mice with DSS-induced depressive behaviors. Upregulating Lcn2 from neuronal activity induced dendritic spine loss and the secreted protein induced chemokine expression and subsequently contributed to microglial activation leading to blood-brain barrier permeability. Moreover, Lcn2 silencing in the PVT alleviated the DSS-induced depressive-like behaviors. The present study demonstrated that elevated Lcn2 in the PVT is a critical factor for DSS-induced depressive behaviors.
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Mice , Humans , Animals , Lipocalin-2/genetics , Midline Thalamic Nuclei , Brain , Inflammatory Bowel Diseases , Proto-Oncogene Proteins c-fos , Mice, Inbred C57BLABSTRACT
Hepatic encephalopathy (HE) is a common complication and an independent risk factor for death in patients with liver cirrhosis. Brain lactate level is associated with the progression and severity of HE, and research on brain lactate level may help to further explain the pathogenesis of HE. This article summarizes the metabolic process of brain lactate, the association between brain lactate level and HE, and the potential therapeutic targets for HE and provides a reference for clinicians to further systematically evaluate the progression, treatment outcome, and prognosis of patients with HE, in order to reduce the medical burden of patients and improve the prognosis of patients with HE.
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A BBB co-culture cell model consisting of rat brain microvascular endothelial cells (BMEC) and astrocytes (AS) was established to study the effect of Angelica dahurica coumarins on the transport behavior of puerarin across blood-brain barrier (BBB) in vitro and in vivo. The barrier function of this model was evaluated by measuring the transendothelial resistance, phenol red permeability and BBB related protein expression. The permeability assay and western blot methods were performed to study the effects of Angelica dahurica coumarins on the BBB permeability and the expression of BBB related protein. The animal experiment protocols in this study were approved by the Animal Ethics Committee of Xi'an Jiaotong University (Animal Ethics No.: 2021-1329). The results showed that the established BMEC/AS co-culture model could be used to evaluate drug transport across BBB in vitro. After combined with Angelica dahurica coumarins, the transport capacity of puerarin was significantly increased in vitro and in vivo. Additionally, Angelica dahurica coumarins enhanced BBB permeability and inhibited the protein expression of P-glycoprotein (P-gp), zonula occludens-1 (ZO-1) and occludin. Angelica dahurica coumarins might increase BBB permeability by inhibiting the expression of P-gp and tight junction protein, thereby increasing the content of puerarin in brain tissue.
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Since LIU Hejian proposed the concept of sweat pore， the theory of sweat pore has experienced accelerated development. Especially with the advances in modern human anatomy and physiology， the microscopic anatomy of sweat pore begins to focus on the intercellular space， ion channels and other membranous space with channels， pores， doors， etc.， which exert the functions of exchanging fluid， information， and energy inside and outside blood vessels and discharging metabolic wastes so as to maintain the normal operation of organs. Therefore， sweat pore is the structural basis for the movement of Qi and the central link of Qi-fluid exchange in the body. The brain， as the house of original spirit， is in charge of the spirit of five Zang-organs. The brain sweat pore is pivotal for the circulation of Qi， blood， and fluid in the brain， and it is the structural basis for the normal physiological functions of the brain. The dysfunction of the brain sweat pore will cause the stagnation of Qi and the abnormal transport of blood and fluid. It will cause the abnormal exchange of Qi， liquid and other material and information， which fail to nourish the original spirt and cause the loss of vital activity， eventually leading to consciousness and emotion disorders. The treatment should focus on opening the brain sweat pore， smoothing the exchange of Qi and fluid inside and outside the pore， and restoring the Qi movement， so as to cure encephalopathy. At present， western medicine treatment of encephalopathy needs to solve the problem of drug efflux from the blood-brain barrier and improve the effective concentration of drugs into the brain. The structure and function of brain sweat pore is similar to those of the blood-brain barrier. The aromatic resuscitative medicines and wind-extinguishing medicines can open the brain sweat pore. When being combined with other medicines， they can lead the medicine to enter the brain to restore the Qi movement of the brain sweat pore and enhance the therapeutic effect. Liver-pacifying wind-extinguishing medicines， insect medicines， tonifying medicines， heat-clearing toxin-removing medicines， and damp-draining medicines can treat pathological factors such as wind， phlegm， stasis， deficiency， toxin， and dampness， respectively. These medicines， combined with the medicines with the tropism to brain meridians， can open the brain sweat pore and guide the medicine into the brain to enhance the effective concentration of the medicine， thereby enhancing the efficacy against encephalopathy.
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Glioma is a common primary malignant brain tumor. At present, the main clinical treatment is surgical resection combined with radiotherapy and chemotherapy. Due to the selective permeability of the blood-brain barrier and the characteristics of multi-drug resistance of tumor cells, the therapeutic effect is not ideal. In recent years, studies have found that borneol could open the blood-brain barrier and promote the infiltration of chemotherapy drugs. When borneol is combined with or co-carried with chemotherapy drugs, chemotherapy drugs could target more glioma tissues and increase efficacy. The preclinical studies on the combination of borneol and chemotherapy drugs in recent years were reviewed in this article, in order to provide useful reference for the treatment of glioma.
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It is a significant challenge to improve the blood-brain barrier (BBB) permeability of central nervous system (CNS) drugs in their development. Compared with traditional pharmacokinetic property tests, machine learning techniques have been proven to effectively and cost-effectively predict the BBB permeability of CNS drugs. In this study, we introduce a high-performance BBB permeability prediction model named balanced-stacking-learning based BBB permeability predictor(BSL-B3PP). Firstly, we screen out the feature set that has a strong influence on BBB permeability from the perspective of medicinal chemistry background and machine learning respectively, and summarize the BBB positive(BBB+) quantification intervals. Then, a combination of resampling algorithms and stacking learning(SL) algorithm is used for predicting the BBB permeability of CNS drugs. The BSL-B3PP model is constructed based on a large-scale BBB database (B3DB). Experimental validation shows an area under curve (AUC) of 97.8% and a Matthews correlation coefficient (MCC) of 85.5%. This model demonstrates promising BBB permeability prediction capability, particularly for drugs that cannot penetrate the BBB, which helps reduce CNS drug development costs and accelerate the CNS drug development process.
Subject(s)
Blood-Brain Barrier , Algorithms , Area Under Curve , Databases, Factual , PermeabilityABSTRACT
Cerebral small vessel disease (CSVD) is an important cause of ischemic stroke and vascular dementia, which brings heavy burden to families and society. The prevention and treatment of CSVD has always been a research hotspot, but its pathogenesis is still not completely clear. This article reviews the pathogenesis of CSVD, including chronic cerebral hypoperfusion, blood-brain barrier dysfunction, vascular endothelial dysfunction, interstitial fluid reflux disorder, inflammatory response, and genetic factors, in order to provide more sufficient theoretical basis for early intervention and treatment of CSVD.
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Objective:To investigate the correlation between paroxysmal slow-wave events (PSWEs) and cerebral small vessel disease (CSVD) and CSVD-related cognitive impairment.Methods:Patients with CSVD visited Weihai Municipal Hospital from March 2021 to April 2022 were included, and sex- and age-matched healthy controls were recruited for cross-sectional analysis. The patients with CSVD were further divided into cognitive impairment group and non-cognitive impairment group. The self-developed Python script was used to detect the PSWE parameters in electroencephalogram records. Montreal Cognitive Assessment (MoCA) and Mini-Mental State Examination (MMSE) were used to evaluate cognitive function. Multivariate logistic regression analysis was used to determine whether PWSE parameters were the independent related factors of CSVD and CSVD-related cognitive impairment. Multiple linear regression analysis was used to determine the correlation between the PSWE parameters and overall cognitive function (MoCA total score) in patients with CSVD. Results:A total of 76 patients with CSVD (including 41 patients with cognitive impairment and 35 patients without cognitive impairment) and 45 healthy controls were included. Compared with the healthy control group, PWSEs in the F3 (left frontal area) and O1 (left occipital area) regions of the CSVD group occurred more frequently and lasted longer (all P<0.05). Multivariate logistic regression analysis showed that the frequency (odds ratio [ OR] 1.080, 95% confidence interval [ CI] 1.023-1.140; P=0.005) and duration ( OR 1.006, 95% CI 1.001-1.011; P=0.023) of PWSEs in the left frontal area, as well as the frequency ( OR 1.052, 95% CI 1.010-1.095; P=0.014) and duration ( OR 1.003, 95% CI 1.000-1.006; P=0.028) of PWSEs in the left occipital region were the independent related factors for CSVD. The frequency ( OR 1.106, 95% CI 1.033-1.183; P=0.004) and duration ( OR1.010, 95% CI 1.003-1.017; P=0.004) of PWSEs in the left frontal area were the independent risk factors for cognitive impairment in patients with CSVD. Multiple linear regression analysis showed that the frequency ( β= –0.242, P=0.045) and duration ( β= –0.235, P=0.046) of PWSEs in the left frontal region were negatively correlated with the overall cognitive function score in patients with CSVD. Conclusions:The frequency and duration of PSWEs in some brain regions of patients with CSVD increase, and there is an independent correlation between PSWEs and cognitive impairment, suggesting that the damage of blood-brain barrier may participate in the pathogenesis of cognitive impairment in patients with CSVD.
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The concept of the glial-vascular unit (GVU) was raised recently to emphasize the close associations between brain cells and cerebral vessels, and their coordinated reactions to diverse neurological insults from a "glio-centric" view. GVU is a multicellular structure composed of glial cells, perivascular cells, and perivascular space. Each component is closely linked, collectively forming the GVU. The central roles of glial and perivascular cells and their multi-level interconnections in the GVU under normal conditions and in central nervous system (CNS) disorders have not been elucidated in detail. Here, we comprehensively review the intensive interactions between glial cells and perivascular cells in the niche of perivascular space, which take part in the modulation of cerebral blood flow and angiogenesis, formation of the blood-brain barrier, and clearance of neurotoxic wastes. Next, we discuss dysfunctions of the GVU in various neurological diseases, including ischemic stroke, spinal cord injury, Alzheimer's disease, and major depression disorder. In addition, we highlight the possible therapies targeting the GVU, which may have potential clinical applications.
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Humans , Neuroglia , Nervous System Diseases , Blood-Brain Barrier , Alzheimer Disease , Glymphatic SystemABSTRACT
The way sporadic Parkinson's disease (PD) is perceived has undergone drastic changes in recent decades. For a long time, PD was considered a brain disease characterized by motor disturbances; however, the identification of several risk factors and the hypothesis that PD has a gastrointestinal onset have shed additional light. Today, after recognition of prodromal non-motor symptoms and the pathological processes driving their evolution, there is a greater understanding of the involvement of other organ systems. For this reason, PD is increasingly seen as a multiorgan and multisystemic pathology that arises from the interaction of susceptible genetic factors with a challenging environment during aging-related decline.