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ObjectiveTo explore the possible mechanism of the Yiqi Jiedu formula （YQ） in treating ischemic stroke （IS） from the perspective of the microbial-gut-brain axis （MGBA）. MethodRats were randomly divided into five groups， with six in each group， including sham surgery group， model group， and low， medium， and high dose YQ groups （1， 5， and 25 mg·kg-1）. Except for the sham surgery group， all other groups were established with a middle cerebral artery occlusion （MCAO） model using the thread occlusion method. The success of modeling was determined through neurobehavioral scoring， and the protective effect of YQ on IS was evaluated. Then， the changes in gut microbiota before and after MCAO modeling and YQ administration were compared using 16S rDNA sequencing technology， and the possible biological pathways related to the effect of this formula were analyzed. The expression of inflammatory factors such as interleukin-6 （IL-6）， interleukin-17A （IL-17A）， and interleukin-10 （IL-10） in serum was detected by enzyme-linked immunosorbent assay （ELISA）. Western blot was used to detect the expression of tight junction proteins ZO-1 and Occludin in brain and intestinal tissue， and hematoxylin-eosin staining （HE） was used to observe pathological changes in the cerebral cortex and colon， so as to validate the possible mechanism of action. ResultYQ significantly improved the neurobehavioral score of MCAO rats （P<0.01） and played a good regulatory role in intestinal microbial disorders caused by enriched pathogens and opportunistic pathogens during the acute phase. Among them， significantly changed microorganisms include Morgentia， Escherichia Shigella， Adlercreutzia， and Androbacter. Bioinformatics analysis found that these bacteria may be related to the regulation of inflammation in the brain. Compared with the blank group， the detection of inflammatory factors in the serum of IS model rats showed an increase in inflammatory factors IL-6 and IL-17A （P<0.01） and a decrease in the content of anti-inflammatory factor IL-10 （P<0.01）. Compared with the model group， the content of inflammatory factors IL-6 and IL-17A in the serum of the treatment group decreased （P<0.05）， and that of anti-inflammatory factor IL-10 increased （P<0.01）. The expression results of barrier proteins ZO-1 and Occludin in brain and intestinal tissue showed that the expression levels of both decreased in IS model rats （P<0.05）， while the expression levels of both increased in the treatment group （P<0.05）. ConclusionAcute cerebral ischemia can lead to an imbalance of intestinal microbiota and damage to the intestinal barrier， and it can increase intestinal permeability. YQ can regulate intestinal microbiota imbalance caused by ischemia， inhibit systemic inflammatory response， and improve the disruption of the gut-blood brain barrier， preventing secondary cascade damage to brain tissue caused by inflammation. The MGBA may be an important mechanism against the IS.
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ObjectiveTo explore the mechanism of Wenyang Jieyu prescription in regulating hippocampal neuron apoptosis and improving synaptic plasticity in the mouse model of depression induced by maternal separation combined with restraint stress. MethodThe mice on postnatal day 0 （PD0） were randomly assigned into a control group （n=10） and a modeling group （n=50）. Maternal separation combined with restraint stress was adopted to establish the mouse model of depression， and the modeled mice were randomized into model， Wenyang prescription， Jieyu prescription， Wenyang Jieyu prescription， and fluoxetine groups （n=10） on the weaning day （PD21）. From PD21 to PD111， the mice were fed with the diets mixed with corresponding medicines. The sucrose preference test， open field test， O-maze test， and novel object recognition test were then conducted to evaluate the depression， memory， and learning abilities of mice. Immunohistochemistry （IHC） was employed to measure the atomic absorbance （AA） of postsynaptic density protein 95 （PSD95） in the hippocampus. Terminal-deoxynucleoitidyl transferase-mediated nick-end labeling （TUNEL） was employed to detect the apoptosis of hippocampal neurons. Western blot was employed to determine the protein levels of brain-derived neurotrophic factor （BDNF）， phosphorylated tyrosine kinase receptor B/tyrosine kinase receptor B （p-TrkB/TrkB）， phosphorylated protein kinase B/protein kinase B （p-Akt/Akt）， phosphorylated mammalian target of rapamycin/mammalian target of rapamycin （p-mTOR/mTOR）， B-cell lymphoma-2 （Bcl-2）， Bcl-2-associated X （Bax）， cysteinyl aspartate-specific proteinase-3 （Caspase-3）， synaptophysin （Syn）， and PSD95. ResultCompared with the control group， the modeling decreased the sucrose preference rate， time spent in central zone within 5 min， total movement distance， time spent in the open arm， and cognition index （P<0.01）. Furthermore， it decreased the expression of PSD95， increased the neuron apoptosis in the hippocampus （P<0.01）， down-regulated the protein levels of BDNF， p-TrkB/TrkB， p-Akt/Akt， p-mTOR/mTOR， Bcl-2， PSD95， and Syn （P<0.01）， and up-regulated the protein levels of Bax and Caspase-3 （P<0.05） in the hippocampus. Compared with the model group， Wenyang Jieyu prescription and fluoxetine increased the sucrose preference rate， time spent in central zone within 5 min， total movement distance， time spent in the open arm， and cognition index （P<0.05， P<0.01）. Moreover， the drugs increased the expression of PSD95， reduced the neuron apoptosis （P<0.01）， up-regulated the protein levels of BDNF， p-TrkB/TrkB， p-Akt/Akt， p-mTOR/mTOR， Bcl-2， PSD95， and Syn （P<0.01）， and down-regulated the protein levels of Bax and Caspase-3 （P<0.01）. ConclusionWenyang Jieyu prescription outperformed Wenyang prescription and Jieyu prescription in the treatment of the depressive behavior induced by maternal separation combined with restraint stress in mice. It exerted the therapeutic effect by reducing the hippocampal neuron apoptosis and improving the synaptic plasticity via the BDNF/Akt/mTOR pathway.
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ObjectiveTo explore the syndromes and mechanisms of depression induced by maternal separation （MS） combined with chronic restraint stress （RS） in mice. MethodOn postnatal day 0 （PD0）， the offspring mice were randomized into a blank group （NC） and a modeling group. The mouse model of depression was established by MS+RS for 21 days. After removal of female mice on PD21， the modeled mice were randomized into model， Wenyang， Jieyu， Wenyang Jieyu， and fluoxetine groups， with 15 mice in each group. The sucrose preference， tail suspension， and open field tests were carried out to evaluate the anxiety and depression-like behavior in mice. Enzyme-linked immunosorbent assay was used to measure the adrenocorticotrophic hormone （ACTH） and corticosterone （CORT） levels in mouse plasma. High performance liquid chromatography-electrochemical detector was used to determine the content of monoamine neurotransmitters in the hippocampus. Real-time fluorescence quantitative polymerase chain reaction was employed to determine the mRNA levels of genes in the 5-hydroxytryptamine （5-HT） system， hypothalamic-pituitary-adrenal （HPA） axis， and brain-derived neurotrophic factor （BDNF） signaling pathway in the hippocampus. Immunohistochemistry was employed to determine the expression levels of proteins in the 5-HT system and HPA axis in the hippocampus. The Simple Western system was used to determine the protein levels of BDNF and tyrosine kinase receptor B （TrkB） in the hippocampus. ResultCompared with the NC group， the model group exhibited depression-like behavior， which was significantly relieved by Wenyang Jieyu prescription and fluoxetine. Compared with the NC group， the model group showed elevated levels of CORT and ACTH in the plasma （P<0.01）， which， however， were lowered by Wenyang Jieyu prescription and fluoxetine （P<0.05， P<0.01）. Compared with the NC group， the model group showed inhibited expression of neurotransmitters in the hippocampus （P<0.05， P<0.01）， while Wenyang Jieyu prescription and fluoxetine restored the expression of neurotransmitters （P<0.05， P<0.01）. Compared with NC group， the model group showed inhibition of the 5-HTergic nerve and abnormal activation of the HPA axis， and Wenyang Jieyu prescription and fluoxetine regulated the abnormal state of the 5-HTergic nerve and HPA axis. Compared with NC group， the modeling down-regulated the mRNA and protein levels of BDNF and TrkB in the hippocampus （P<0.05， P<0.01）， which， however， were recovered in Wenyang， Jieyu， Wenyang Jieyu， and fluoxetine groups （P<0.05， P<0.01）. ConclusionThe mouse model of depression induced by MS+RS may present the syndrome of Yang deficiency and liver depression. Wenyang Jieyu prescription may increase the content of hippocampal neurotransmitters by regulating the 5-HT system and the BDNF signaling pathway mediated by the HPA axis， thereby alleviating depression-like behavior in mice.
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Background Chronic excessive exposure to fluoride can cause damage to the central nervous system and a certain degree of learning and memory impairment. However, the associated mechanism is not yet clear and further exploration is needed. Objective Using 4D unlabelled quantitative proteomics techniques to explore differentially expressed proteins and their potential mechanisms of action in chronic excessive fluoride exposure induced brain injury. Methods Twenty-four SPF-grade adult SD rats, half male and half male, were selected and divided into a control group and a fluoride group by random number table method, with 12 rats in each group. Among them, the control group drank tap water (fluorine content<1 mg·L−1), the fluoride group drank sodium fluoride solution (fluorine content 10 mg·L−1), and both groups were fed with ordinary mouse feed (fluoride content<0.6 mg·kg−1). After 180 d of feeding, the SD rats were weighed, and then part of the brain tissue was sampled for pathological examination by hematoxylin-eosin (HE) staining and Nissl staining. The rest of the brain tissue was frozen and stored at −80 ℃. Three brain tissue samples from each group were randomly selected for proteomics detection. Differentially expressed proteins were screened and subcellular localization analysis was performed, followed by Gene Ontology (GO) function analysis, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, cluster analysis, and protein-protein interaction analysis. Finally, Western blotting was used to detect the expression levels of key proteins extracted from the brain tissue samples. Results After 180 d of feeding, the average weight of the rats in the fluoride group was significantly lower than that in the control group (P<0.05). The brain tissue stained with HE showed no significant morphological changes in the cerebral cortex of the fluoride treated rats, and neuron loss, irregular arrangement of neurons, eosinophilic changes, and cell body pyknosis were observed in the hippocampus. The Nissl staining results showed that the staining of neurons in the cerebral cortex and hippocampus of rats exposed to fluoride decreased (Nissl bodies decreased). The proteomics results showed that a total of 6927 proteins were identified. After screening, 206 differentially expressed proteins were obtained between the control group and the fluoride group, including 96 up-regulated proteins and 110 down-regulated proteins. The differential proteins were mainly located in cytoplasm (30.6%), nucleus (27.2%), mitochondria (13.6%), plasma membrane (13.6%), and extracellular domain (11.7%). The GO analysis results showed that differentially expressed proteins mainly participated in biological processes such as iron ion transport, regulation of dopamine neuron differentiation, and negative regulation of respiratory burst in inflammatory response, exercised molecular functions such as ferrous binding, iron oxidase activity, and cytokine activity, and were located in the smooth endoplasmic reticulum membrane, fixed components of the membrane, chloride channel complexes, and other cellular components. The KEGG significantly enriched pathways included biosynthesis of secondary metabolites, carbon metabolism, and microbial metabolism in diverse environments. The results of differential protein-protein interaction analysis showed that the highest connectivity was found in glucose-6-phosphate isomerase (Gpi). The expression level of Gpi in the brain tissue of the rats in the fluoride group was lower than that in the control group by Western blotting (P<0.05). Conclusion Multiple differentially expressed proteins are present in the brain tissue of rats with chronic fluorosis, and their functions are related to biosynthesis of secondary metabolites, carbon metabolism, and microbial metabolism in diverse environments; Gpi may be involved in cerebral neurological damage caused by chronic overdose fluoride exposure.
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Based on the neurovascular unit(NVU), neurovascular coupling functions as a barrier to maintain the homeostasis of the microenvironment by regulating the signaling and metabolic activity of nerve cells and capillaries. Widely dispersed across the retina, the NVU is essential to preserving its normal physiological function. A disturbance in retinal neurovascular homeostasis produced by a range of factors can result in a variety of retinal disorders, such as diabetic retinopathy(DR), glaucoma, retinitis pigmentosa(RP)and age-related macular degeneration(ARMD). The retina also has a widespread distribution of brain-derived neurotrophic factor(BDNF), which functions to promote neuron growth and repair damage by binding to its receptor TrkB. In recent years, BDNF was found to play a protective role against damage in the early stage of retinal neurovascular homeostasis imbalance, often known as the neurodegenerative stage. It also helps to reduce the production of pro-angiogenic substances of neurological origin and offers a fresh approach for the early detection and treatment of associated eye disorders.
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Alzheimer's disease is a common central neurodegenerative disease， mainly manifested by cognitive impairment and non-cognitive neuropsychiatric symptoms that severely affect patients' daily life and behavioral functioning. The pathogenesis of Alzheimer's disease is still unclear， and the western medicine currently used to treat Alzheimer's disease is only symptomatic， with a single pathway， limited efficacy， and many side effects. In recent years， with the deepening of research on Alzheimer's disease， the study and application of traditional Chinese medicine （TCM） in the treatment of Alzheimer's disease have gradually increased. Several studies have shown that TCM and its effective components can exert anti-Alzheimer's disease effects by regulating molecular mechanisms such as pathological protein production and aggregation， oxidative stress， neuroinflammation， ferroptosis， mitochondrial dysfunction， neurogenesis and neurotransmission， and brain-gut axis. This paper summarized the research progress of TCM in the treatment of Alzheimer's disease in recent years， so as to provide a reference for further study of the specific mechanism of TCM in the prevention and treatment of Alzheimer's disease and the discovery of effective components of TCM.
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The theory of "brain-heart-kidney-semen chamber" axis is proposed based on the basic theories of traditional Chinese medicine， the modern physiological characteristics of men's diseases， and clinical practice. According to this theory， dysfunctions of the brain， heart， kidney， and semen chamber are the core mechanisms for the occurrence of premature ejaculation， and the loss of control of the opening and closing of the seminal orifices due to the dysfunction of the semen chamber is the final link in the occurrence of premature ejaculation. The treatment of premature ejaculation based on the theory of "brain-heart-kidney-essence chamber" axis highlights the overall regulation of the Zang-fu organs involved in the disease， while focusing on the simultaneous treatment of the mind and body. By exploring the biological basis of the "brain-heart-kidney-essence chamber" axis and premature ejaculation， we propose that the biological basis of premature ejaculation and the axis is mainly related to the function decline of the local brain area， neuromodulation malfunction， central neurotransmitter imbalance， endocrine disorders， and enhanced sensory afferents of the penis. This study aims at providing a new approach for the prevention and treatment of premature ejaculation by traditional Chinese medicine and a scientific basis for the development of more effective therapeutic methods.
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Objective To explore the dynamic changes and mechanisms of neurological and cognitive functions in mice with traumatic brain injury (TBI). Methods Totally 60 12⁃month⁃old Balb/ c mice were divided into control group (10 in group) and TBI group (50 in group). TBT model mice were divided into 5 subgroups according to the time of model construction, including model 1 day, model 1 day, model 3 day, model 7 day, model 14 days and model 28 days group with 10 in each group. At the 29th day of the experiment, neurological scores and step down tests were carried out. After the test, the mice were sacrificed for brains which were detected by immunohistochemistry staining, inflammatory cytokine tests and Western blotting. Results Compared with the control group, the neurological scores of mice in TBI group increased, and then decreased after the 7th day when the scores reached the peak. However, the latency of step down errors was lower than control group, and the number of step down errors was higher than control group which had no changes. Compared with the control group, the expression of lonized calcium⁃binding adapter molecule 1(IBA1), chemokine C⁃X3⁃C⁃motif ligand1 (CX3CL1), C⁃X3⁃C chemokine receptor 1(CX3CR1), NOD⁃like receptor thermal protein domain associated protein 3 (NLRP3), and phosphorylation nuclear factor(p⁃NF)⁃κB in TBI group increased and reached to the peak at the 7th day, and then started to decrease. At the same time, the levels of inflammatory cytokines interleukin⁃6(IL⁃6) and tumor necrosis factor⁃α(TNF⁃α) first increased to the peak, and then began to decrease. However, compared with the control group, the expression of amyloid β(Aβ) protein and p⁃Tau protein in the model group continued to increase at all time. Conclusion The TBI model caused continuous activation of microglia along with inflammatory response, which first increased and then decreased, resultsing in neurological scores changes. In addition, the inflammatory response may act as a promoter of Aβ protein deposition and Tau protein phosphorylation, leading to cognitive impairment in mice.
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Objective To clarify the expression and distribution of brain⁃derived neurotrophic factor (BDNF) in the cerebrum of plateau yaks and cattle, and to explore the relationship between BDNF function and the adaptability of altitude hypoxia. Methods Five yaks and five cattles were selected.The content and distribution of BDNF in frontal lobe, temporal lobe, parietal lobe, occipital lobe, cerebrum white matter and hippocampus of yak and cattle were analyzed by Real⁃time PCR, Western blotting and Immunohistochemistry. Results Real⁃time PCR result showed that BDNF mRNA expression in the cerebrum of yaks and cattles was highest in temporal cortex, followed by hippocampus, parietal cortex, occipital cortex and frontal cortex, and lowest in white matter. Western blotting results showed that the content of BDNF protein in the cerebrum of yaks was the highest in temporal cortex,followed by hippocampus. The content of BDNF protein in other tissues was parietal cortex, frontal cortex and cerebrum white matter, and the content of BDNF protein was the lowest in occipital cortex. The content of BDNF protein intlecerebrum of cattles was the highest in the temporal cortex, followed by the hippocampus. The content of BDNF protein in other tissues was parietal cortex, occipital cortex and frontal cortex in descending order, and the protein content in cerebrum white matter was the lowest. Immunohistochemical results showed that the positive expression of BDNF protein in the cerebrum of yaks and cattles was basically similar, mainly distributed in the granulosa cells and glial cells in the frontal cortex, temporal cortex, parietal cortex and occipital cortex, glial cells in cerebrum white matter, pyramidal cell layer and polyform cell layer in the hippocampus. There was the small amount of distribution in Martinotti cells and the molecular layer of hippocampus in the cerebral cortex. Conclusion BDNF mRNA and protein are distributed and expressed in different brain regions of yaks and cattles, but the expression level different, which is speculated to be closely related to the specific functions of different cerebrum regions. The expression level of the cerebrum of yak is higher than that of cattle except occipital cortex, suggesting that it is related to the altitude hypoxic environment. BDNF may play an important role in enhancing hypoxic tolerance and protecting internal environmental homeostasis in the process of animal adaptation to hypoxic environment.
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Objective The volume and cortical thickness of gray matter in patients with multiple sclerosis (MS) and neuromyelitis optica (NMO) were compared and analyzed by voxel⁃based morphometry (VBM) and surface⁃based morphometry (SBM), and the differences in the structural changes of gray matter in the two diseases were discussed. Methods A total of 21 MS patients, 16 NMO patients and 19 healthy controls were scanned by routine MRI sequence. The data were processed and analyzed by VBM and SBM method based on the statistical parameter tool SPM12 of Matlab2014a platform and the small tool CAT12 under SPM12. Results Compared with the normal control group (NC), after Gaussian random field (GRF) correction, the gray matter volume in MS group was significantly reduced in left superior occipital, left cuneus, left calcarine, left precuneus, left postcentral, left central paracentral lobule, right cuneus, left middle frontal, left superior frontal and left superior medial frontal (P<0. 05). After family wise error (FWE) correction, the thickness of left paracentral, left superiorfrontal and left precuneus cortex in MS group was significantly reduced (P<0. 05). Compared with the NC group, after GRF correction, the gray matter volume in the left postcentral, left precentral, left inferior parietal, right precentral and right middle frontal in NMO group was significantly increased (P<0. 05). In NMO group, the volume of gray matter in left middle occipital, left superior occipital, left inferior temporal, right middle occipital, left superior frontal orbital, right middle cingulum, left anterior cingulum, right angular and left precuneus were significantly decreased (P<0. 05). Brain regions showed no significant differences in cortical thickness between NMO groups after FWE correction. Compared with the NMO group, after GRF correction, the gray matter volume in the right fusiform and right middle frontal in MS group was increased significantly(P<0. 05). In MS group, the gray matter volume of left thalamus, left pallidum, left precentral, left middle frontal, left middle temporal, right pallidum, left inferior parietal and right superior parietal were significantly decreased (P<0. 05). After FWE correction, the thickness of left inferiorparietal, left superiorparietal, left supramarginal, left paracentral, left superiorfrontal and left precuneus cortex in MS group decreased significantly (P<0. 05). Conclusion The atrophy of brain gray matter structure in MS patients mainly involves the left parietal region, while NMO patients are not sensitive to the change of brain gray matter structure. The significant difference in brain gray matter volume between MS patients and NMO patients is mainly located in the deep cerebral nucleus mass.
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Emerging evidences suggest that ferroptosis plays a vital role in the pathophysiological process of brain injury after Ischemic stroke. Accumulating evidence supports pharmacological inhibition of ferroptosis as a therapeutic target for brain injury after Ischemic stroke through activating nuclear factor erythroid 2-related factor 2 (Nrf2), which transcriptionally controls many key components of the ferroptosis pathway. In this review, briefly describe ferroptosis processes and the roles they play in contributing to brain injury after ischemic stroke in the brain. We then provide a critical overview of the relationship between Nrf2 signalling and ferroptosis. With a focus on discuss how therapeutic modulation of the Nrf2 pathway is a viable strategy to explore in the treatment of ferroptosis-driven brain injury after Ischemic stroke.
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Aim To investigate the dynamic time-course changes in neuronal cytoskeleton after acute ischemia and reperfusion in rats. Methods Reperfusion was performedin rats by blocking the middle cerebralarteryfor 90 min, then therats wereobserved and collected at different time points. The brain damage wasobserved by Nissl staining,and neurobehavioural function was evaluated with neurological deficit score and forelimb placement test. The cellular changes in the alternations of cytoskeletal elements including microtubule associated protein 2 (MAP2) and neurofilament heavy chain (NF-H) were observed by immunohistochemistry staining and Western blot. Impaired axons, dendrites and cytoskeletal alternations were detected by electron microscope. Results Brain damage and neurobehavioural function were gradually aggravated with the prolongation of reperfusion. Brain damage appeared earlier and more severe in striatum than in cortex. Moreover, decreased MAP2-related and increased NF-H-related immunoreactive intensities were found in the ischemic areas. Impaired cytoskeletal arrangement and reduced dense were indicated. Damaged cytoskeletal components such as microtubules and neurofilament arrangement, decreased axonal filament density, and swelled dendrites were observed after cerebral ischemia reperfusion by ultrastructural observations. Conclusions Different brain regions have diverse tolerance to ischemia-reperfusion injury. Major elements of neuronal cytoskeleton show dynamic responses to ischemia and reperfusion, which may further contribute to brain damage and neurological impairment following MCAO and reperfusion.
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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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Since the 19th century, the emergence of model systems has helped researchers further understand cellular signaling pathways, identify potential drug targets, and conduct environmental toxicological studies. Exogenous chemicals, such as pollutants, drugs, and industrial chemicals, may affect brain biological processes and functions and eventually lead to neurological diseases. However, the brain is a complex and well-organized human organ, which is fundamentally different from any existing model system. Animal models may not be able to completely simulate the human brain in testing the neurotoxicity of environmental pollutants due to species differences. Human brain organoids, generated from human pluripotent stem cells, are emerging model systems for neurotoxicological research in line with the real situation of human body at the level of genome, transcriptome, and metabolome, and provide an effective platform for testing neurotoxicity of environmental toxins. We reviewed the latest development of brain organoids technology and its application in the evaluation of environmental neurotoxins, and provided new insights into the application of brain organoids in environmental neurotoxicology.
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ObjectiveTo explore the effect of brain-computer interface (BCI) based on visual, auditory and motor feedback combined with transcranial direct current stimulation (tDCS) on upper limb function in stroke patients. MethodsFrom March to October, 2023, 45 stroke inpatients in Xuzhou Rehabilitation Hospital and Xuzhou Central Hospital were divided into BCI group (n = 15), tDCS group (n = 15) and combined group (n = 15) randomly. All the groups received routine rehabilitation, while BCI group received BCI training, tDCS group received tDCS, while the combined group received tDCS and followed by BCI training immediately, for four weeks. They were assessed with Fugl-Meyer Assessment-Upper Extremities (FMA-UE), Action Research Arm Test (ARAT), modified Barthel Index (MBI) and delta-alpha ratio (DAR) and power ratio index (PRI) of electroencephalogram before and after treatment. ResultsThe scores of FMA-UE, ARAT and MBI increased in all the groups after treatment (|t| > 5.350, P < 0.001), and all these indexes were the best in the combined group (F > 3.366, P < 0.05); while DAR and PRI decreased in all the groups (|t| > 2.208 , P < 0.05), they were the best in the combined group (F > 5.224, P < 0.01). ConclusionBCI based on visual, auditory and motor feedback combined with tDCS can further improve the motor function of upper limbs and the activities of daily living of stroke patients.
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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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ObjectiveTo research the mechanism underlying the effect of raw and processed Aurantii Fructus Immaturus switched to Zhishi Shaoyaosan （ZSS） on constipation-predominant irritable bowel syndrome （C-IBS） rats via the brain-gut-microbiota axis. MethodEighty rats were randomly divided into the blank， model， positive drug （pinaverium bromide， 15.625 mg·kg-1）， raw ZSS， stir-fried ZSS， bran-fried ZSS， charcoal-fried ZSS and finished ZSS groups （3.75 g·kg-1）， with 10 rats in each group. Except for the blank group， which received intragastric administration of 0.9% sodium chloride solution at room temperature， all other groups were administered the ice solution at 0 to 4 ℃ （2 mL·d-1， for a total of 14 d） to establish the C-IBS rat model. The fecal water content and the propulsion rate of small intestine were detected after 14 d of continuous drug administration. The levels of 5-hydroxytryptamine （5-HT）， vasoactive intestinal peptide （VIP）， neuro-peptide Y （NPY）， calcitonin gene-related peptide （CGRP）， substance P （SP）， diamine oxidase （DAO） and D-lactic acid （D-LA） were detected by enzyme linked immunosorbent assay （ELISA）. Hematoxylin-eosin （HE） staining was used to observe the changes in colonic pathological injury in each group. The expression levels of cyclic adenosine monophosphate （cAMP）， protein kinase A （PKA） and aquaporin-3 （AQP3） mRNA in colon tissues were detected by Real-time fluorescence quantitative polymerase chain reaction （Real-time PCR） and the protein expressions of VIP and AQP3 in colon tissues were detected by Western blot. The content of short chain fatty acids （SCFAs） was determined by gas chromatography-mass spectrometry. ResultCompared with the blank group， the fecal water content and intestinal propulsion rate of rat in the model group were significantly decreased （P<0.01）， and the levels of 5-HT， VIP， CGRP and SP in serum were significantly increased. Simultaneously， the NPY levels significantly decreased （P<0.01）， the levels of DAO and D-LA in plasma were significantly increased （P<0.01）， and the mucosal epithelium of colon tissue was slightly damaged， with reduced goblet cells and significantly reduced luminal granules. The mRNA expression levels of AQP3， cAMP and PKA and the protein expression levels of AQP3 and VIP in colon tissue were significantly decreased （P<0.05， P<0.01）. The total amount of SCFAs in feces showed an obvious decreasing trend， with the contents of acetic acid， isobutyric acid， isovaleric acid， valeric acid and caproic acid decreased significantly， while the contents of propionic acid and butyric acid increased significantly （P<0.05， P<0.01）. Compared with the model group， the treatment groups increased the intestinal propulsion rate， improved the intestinal mucosal barrier function， and adjusted the level of serum brain-gut peptide in C-IBS rats （P<0.05， P<0.01）. The expression levels of AQP3， cAMP， PKA mRNA and VIP， AQP3 protein in colon tissue of rats in all treatment groups were increased. All the treatment groups had a significant downregulation of the content of SCFAs except for isobutyric acid in rat feces， and the effect of ZSS prepared by the bran-fried Aurantii Fructus Immaturus was superior than that of other ZSS. ConclusionThe raw and processed Aurantii Fructus Immaturus switched to ZSS could influence the brain-gut-microbiota axis to treat C-IBS rats and it is more reasonable to use bran-fried Aurantii Fructus Immaturus in ZSS.
ABSTRACT
Chronic constipation （CC） is one of the most common functional gastrointestinal diseases. At present， the overall therapeutic effect of CC is still not satisfactory worldwide， which seriously affects the quality of life and social function of patients. The etiology and pathophysiological mechanism of constipation are still unclear. It involves comprehensive factors such as heredity， social psychology， diet， intestinal flora imbalance， intestinal motility disorder， visceral sensitivity change， pelvic floor muscle group dysfunction and enteric nervous system （ENS） disorder. Among them， the abnormal factors of the brain-gut-microbiome axis are particularly significant. The brain-gut-microbiome axis is a complex network of interactions between the intestine and the brain， integrating and coordinating the physiological functions and pathological processes of the gastrointestinal tract. Microorganisms in the intestinal lumen play an important role in it， and can communicate with the intestinal tract and the central nervous system through nerve， endocrine and immune pathways. As a key brain-gut peptide in the regulation pathway of the brain-gut-microbiome axis， 5-hydroxytryptamine （5-HT） is involved in the regulation of gastrointestinal motility， sensation and secretion. The abnormal conduction of the 5-HT signaling pathway is closely related to the occurrence and development of constipation. Traditional Chinese medicine（TCM） is a unique precious resource in China， which has good curative effects and safety. In recent years， it has received extensive attention in the treatment of constipation. TCM and active ingredients， acupuncture and massage specifically regulate 5-HT signal transmission， so that the expressions of related molecules tend to be suitable for individual disease state levels to effectively improve constipation symptoms， with unique advantages. Therefore， this study used ''constipation''， ''intestinal flora''， ''5-HT''， and ''traditional Chinese medicine'' as the keywords to search PubMed， China National Knowledge Infrastructure （CNKI） and other literature databases. The correlation between 5-HT and constipation as well as brain-gut-microbiome axis and the research progress of TCM intervention in the 5-HT signaling pathway in the treatment of constipation were reviewed in order to explore the potential therapeutic value of 5-HT system in this disease and provide references for subsequent research.
ABSTRACT
ObjectiveTo decipher the mechanism of Wenxiao powder in alleviating corticosterone-induced depression-like behaviors in mice. MethodMale ICR mice were randomized into normal， model， paroxetine （20 mg·kg-1）， and low- and high-dose （3.27， 6.54 g·kg-1， respectively） Wenxiao powder groups. The mice in normal and model groups received equal volume of saline. Other groups except the normal group were injected with corticosterone subcutaneously 0.5 h after gavage to induce depression. Mice were tested for depression-like behaviors after drug administration. Enzyme-linked immunosorbent assay （ELISA） was performed to measure the corticosterone content in the serum. Nissl staining was performed to observe the damage of hippocampal neurons. Immunofluorescence staining was employed to observe the expression of double cortin （DCX） in the dentate gyrus （DG） of the hippocampus. Western blot was employed to determine the expression of proteins in the brain-derived neurotrophic factor （BDNF）/tyrosine kinase receptor B （TrkB）/extracellular signal-regulated kinase （ERK）/cAMP-response element-binding protein （CREB） pathway in the hippocampus. ResultCompared with the normal group， the model group showed decreased sucrose preference rate， increased immobility time in the tail suspension test （P<0.01）， and reduced residence time in the central area of the open field and the total movement distance （P<0.05， P<0.01）. In addition， the modeling elevated the corticosterone level in the serum （P<0.01）， decreased the volume and intensified the nuclear staining of hippocampal neurons in the DG area， reduced the expression of DCX in the DG area， and down-regulated the protein levels of BDNF， phosphorylated （p）-TrkB， p-ERK， and p-CREB in the hippocampus （P<0.05， P<0.01）. Compared with the model group， low-dose Wenxiao powder improved the mouse behavivors in the sucrose preference， open field， and tail suspension tests （P<0.05， P<0.01）， and high-dose Wenxiao powder improved the behaviors in the sucrose preference and open field tests （P<0.05， P<0.01）. In addition， Wenxiao powder lowered the serum corticosterone level （P<0.01） and recovered the structure and morphology of neurons with obvious nuclei and presence of Nissl bodies in the DG area of the hippocampus. Moreover， Wenxiao powder at both doses promoted the expression of DCX in the DG area， and high-dose Wenxiao powder up-regulated the protein levels of BDNF， p-TrkB， p-ERK， and p-CREB in the hippocampus （P<0.05， P<0.01）. ConclusionWenxiao powder can alleviate corticosterone-induced depression-like behaviors and promote neurogenesis in mice possibly by activating the BDNF/TrkB/ERK/CREB signaling pathway.
ABSTRACT
Acute hypobaric hypoxic brain damage is a potentially fatal high-altitude sickness. Autophagy plays a critical role in ischemic brain injury, but its role in hypobaric hypoxia (HH) remains unknown. Here we used an HH chamber to demonstrate that acute HH exposure impairs autophagic activity in both the early and late stages of the mouse brain, and is partially responsible for HH-induced oxidative stress, neuronal loss, and brain damage. The autophagic agonist rapamycin only promotes the initiation of autophagy. By proteome analysis, a screen showed that protein dynamin2 (DNM2) potentially regulates autophagic flux. Overexpression of DNM2 significantly increased the formation of autolysosomes, thus maintaining autophagic flux in combination with rapamycin. Furthermore, the enhancement of autophagic activity attenuated oxidative stress and neurological deficits after HH exposure. These results contribute to evidence supporting the conclusion that DNM2-mediated autophagic flux represents a new therapeutic target in HH-induced brain damage.