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1.
Anim Biosci ; 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38419531

RESUMO

Objective: This study was conducted to investigate the effect of slaughter age on carcass traits, meat quality, and the relative mRNA levels of lipid metabolism-related genes in different muscles of Taihang black goats. Methods: In this study, the triceps brachii (TB), longissimus dorsi (LD) and gluteus (GL) muscles of 15 grazing Taihang black goats slaughtered at the age of 2, 3, and 4(designated as 2-year-old, 3-year-old, and 4-year-old, respectively) were collected. The differences in carcass shape, meat quality, amino acid composition and lipid metabolism gene expression among Taihang black goats of different ages and from different plant parts were compared. Results: Compared with goats at other ages, goats slaughtered at the age of 4 had greater live and carcass weights, meat weights, bone weights and skin areas (P<0.05). LD in the 4-years-old had the lowest cooking loss and moisture content. The content of crude protein in 2-year-old was significantly greater than that in the other muscles. The highest fat content was in LD, followed by TB, for goats slaughtered at the age of 4. Eight out of 9 essential amino acids had higher content in the TB compared with other muscles, regardless of age. The total essential amino acid content was highest in the 4-year-old and lowest in the GL muscle at the age of 3. The SREBP-1c and ATGL genes were significantly more abundant in the TB muscle than in the other muscles for goats slaughtered at the age of 2. At the the age of 4, the ATGL and PPARγ genes were significantly more abundant in the GL than in the LD, while the FAS genes were significantly less abundant in the GL than in the other muscles. Similarly, compared with those in goats of other ages, the relative mRNA expression levels of the FAS and H-FABP genes in goats slaughtered at the age of 4 were the highest, and the relative mRNA expression of the PPARγ gene was the lowest (P<0.05). The relative mRNA expression of the H-FABP and FAS genes was positively correlated with the intramuscular fat (IMF) content, while the relative mRNA expression levels of the PPARγ and ATGL genes was negatively correlated with the IMF content. Conclusion: Overall, a better nutritional value was obtained for TB from 4-year-old goats, in which the total essential amino acid and fat contents were greater than those of other muscles. The comprehensive action of lipid metabolism genes was consistent with that of the IMF content, among which the FAS, H-FABP, PPARγ and ATGL genes had positive and negative effects on the process of IMF deposition in Taihang black goats.

2.
Aging (Albany NY) ; 16(2): 1161-1181, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38231472

RESUMO

Chronic Cerebral Hypoperfusion (CCH) is associated with cognitive dysfunction, the underlying mechanisms of which remain elusive, hindering the development of effective therapeutic approaches. In this study, we employed an established CCH animal model to delve into neuropathological alterations like oxidative stress, inflammation, neurotransmitter synthesis deficits, and other morphological alterations. Our findings revealed that while the number of neurons remained unchanged, there was a significant reduction in neuronal fibers post-CCH, as evidenced by microtubule-associated protein 2 (MAP2) staining. Moreover, myelin basic protein (MBP) staining showed exacerbated demyelination of neuronal fibers. Furthermore, we observed increased neuroinflammation, proliferation, and activation of astrocytes and microglia, as well as synaptic loss and microglial-mediated synapse engulfment post-CCH. Utilizing RNA sequencing, differential expression analysis displayed alterations in both mRNAs and circRNAs. Following gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses, both showed significant enrichment in immunological and inflammation-related terms and pathways. Importantly, the differentially expressed circular RNAs (DE circRNAs) exhibited a notable coexpression pattern with DE mRNAs. The ternary circRNA-miRNA-mRNA competing endogenous RNAs (ceRNA) network was constructed, and subsequent analysis reiterated the significance of neuroimmunological and neuroinflammatory dysfunction in CCH-induced neuropathological changes and cognitive dysfunction. This study underscores the potential role of circRNAs in these processes, suggesting them as promising therapeutic targets to mitigate the detrimental effects of CCH.


Assuntos
Disfunção Cognitiva , MicroRNAs , Animais , RNA Circular/genética , RNA Endógeno Competitivo , MicroRNAs/metabolismo , RNA Mensageiro/metabolismo , Inflamação/genética , Disfunção Cognitiva/genética , Redes Reguladoras de Genes
3.
Langmuir ; 40(4): 2362-2368, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38243902

RESUMO

It has long been held that when a droplet impacts obliquely onto a smooth dry surface at normal ambient temperature and pressure, upward splashing can be more easily suppressed than downward splashing. However, in this research, we experimentally find that for a superhydrophobic surface, increasing the wall inclination beforehand suppresses downward splashing and subsequently suppresses upward splashing. The spreading theory for an inclined surface is modified to predict the spreading process on an inclined superhydrophobic wall. Due to the existence of an asymmetric boundary layer between the upward and downward sheet on an inclined wall, the thickness and growth rate of the upward rim are smaller than those of the downward rim; for this reason, the upward side of the spreading sheet splashes more easily on a superhydrophobic wall, considering the theory of a droplet splashing on a flat surface. However, because the upward rim velocity is smaller than the downward rim velocity, the downward lamella splashes more easily than the upward lamella on a smooth surface. We attempt to theoretically describe the interval of the stochastic flow mode (spreading/splashing) that exists in practice for the first time. We also give the phase diagram containing three flow patterns, namely, two-side spreading, upward-only splashing, and two-side splashing, in the parameter space of the Weber number We and the wall inclination angle χ. The theory agrees well with the experimental results.

4.
J Phys Chem B ; 128(8): 1900-1914, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38289261

RESUMO

The competitive behavior of proteins in the reversible adsorption stage plays a crucial role in determining the composition of the protein layer and the subsequent biological responses to the biomaterial. However, such competitive adsorption is a mesoscopic process at physiological protein concentration, and neither a macroscopic experiment nor microscopic MD (molecular dynamics) simulation is suitable to clarify it. Here, we proposed a mesoscopic DPD (dissipative particle dynamics) model to illustrate the competitive process of albumin and fibrinogen on TiO2 surface with its parameters deduced from our previous MD simulation, and proved the model well retained the diffusion and adsorption properties of proteins in the competitive adsorption on the plane surface. We then applied the model to the competitive adsorption on the surfaces with different nanostructures and observed that when the nanostructure size is much larger than that of protein, the increase in surface area is the main influencing factor; when the nanostructure size is close to that of protein, the coordination between the nanostructure and the size and shape of protein significantly affects the competitive adsorption process. The model has revealed many mechanical phenomena observed in previous experimental studies and has the potential to contribute to the development of high-performance biomaterials.


Assuntos
Albuminas , Fibrinogênio , Fibrinogênio/química , Adsorção , Propriedades de Superfície , Materiais Biocompatíveis/química , Simulação de Dinâmica Molecular
5.
J Alzheimers Dis ; 94(2): 815-839, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37334607

RESUMO

BACKGROUND: Both Alzheimer's disease (AD) and aging have aging-related cognitive dysfunction with a high incidence. These neurological diseases cause serious cognitive problems in patients' daily life. But the cognitive dysfunction mechanism in-depth of aging is far less known than that of AD. OBJECTIVE: To reveal the different mechanisms of AD and aging-related cognitive dysfunction, we compared the mechanisms of aging and AD through analysis of differentially expressed genes. METHODS: Mice were divided into four groups (3-month C57BL, 16-month C57BL, 3-month 3xTg AD mice, and 16-month 3xTg AD mice) according to genotype and age. The Morris water maze was employed to investigate the spatial cognition of mice. Differential expressions of genes of AD and aging were analyzed through RNA sequencing and GO, KEGG, Reactome analysis, and the dynamic change trend analysis. Microglia was stained with immunofluorescence and its numbers were counted for analysis. RESULTS: The cognitive function of elderly mice were worse through testing with the Morris water maze. The cognitive function of 16-month 3xTg AD mice were worse than 16-month C57BL mice. The alteration tendencies of DE genes were uncovered, and microglia numbers increased during aging and AD progression through immunofluorescence. CONCLUSION: These results suggest that immune-related pathways might play a critical role in aging and AD-related cognitive dysfunction. Our research will help to provide some new potential targets for treating cognitive dysfunction in aging and AD.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Humanos , Camundongos , Animais , Doença de Alzheimer/metabolismo , Camundongos Transgênicos , Camundongos Endogâmicos C57BL , Cognição , Disfunção Cognitiva/genética , Modelos Animais de Doenças
6.
Nat Commun ; 14(1): 2792, 2023 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-37193714

RESUMO

Real-time monitoring of flow turbulence is very difficult but extremely important in fluid dynamics, which plays an important role in flight safety and control. Turbulence can cause airflow to detach at the end of the wings, potentially resulting in the aerodynamic stall of aircraft and causing flight accidents. Here, we developed a lightweight and conformable system on the wing surface of aircraft for stall sensing. Quantitative data about airflow turbulence and the degree of boundary layer separation are provided in situ using conjunct signals provided by both triboelectric and piezoelectric effects. Thus, the system can visualize and directly measure the airflow detaching process on the airfoil, and senses the degree of airflow separation during and after a stall for large aircraft and unmanned aerial vehicles.

7.
Aging (Albany NY) ; 15(8): 2999-3020, 2023 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-37053022

RESUMO

Chronic cerebral hypoperfusion (CCH)-mediated cognitive impairment is a serious problem worldwide. However, given its complexity, the underlying mechanisms by which CCH induces cognitive dysfunction remain unclear, resulting in a lack of effective treatments. In this study, we aimed to determine whether changes in the expression of RasGRF1, an important protein associated with cognition and synaptic plasticity, underlie the associated impairments in cognition after CCH. We found that RasGRF1 levels markedly decreased following CCH. Through prediction and validation studies, we observed that miRNA-323-3p was upregulated after CCH and could bind to the 3'-untranslated region of Rasgrf1 mRNA and regulate its expression in vitro. Moreover, the inhibition of miRNA-323-3p upregulated Rasgrf1 expression in the hippocampus after CCH, which was reversed by Rasgrf1 siRNA. This suggests that miRNA-323-3p is an important regulator of Rasgrf1. The Morris water maze and Y maze tests showed that miRNA-323-3p inhibition and Rasgrf1 upregulation improved spatial learning and memory, and electrophysiological measurements revealed deficits in long-term potentiation after CCH that were reversed by Rasgrf1 upregulation. Dendritic spine density and mature mushroom spine density were also improved after miRNA-323-3p inhibition and Rasgrf1 upregulation. Furthermore, Rasgrf1 upregulation by miRNA-323-3p inhibition improved dendritic spine density and mature mushroom spine density and ameliorated the deterioration of synapses and postsynaptic density. Overall, RasGRF1 regulation attenuated cognitive impairment, helped maintain structural and functional synaptic plasticity, and prevented synapse deterioration after CCH. These results suggest that Rasgrf1 downregulation by miRNA-323-3p plays an important role in cognitive impairment after CCH. Thus, RasGRF1 and miRNA-323-3p may represent potential therapeutic targets for cognitive impairment after CCH.


Assuntos
Isquemia Encefálica , Disfunção Cognitiva , MicroRNAs , Ratos , Camundongos , Animais , ras-GRF1/genética , ras-GRF1/metabolismo , ras-GRF1/farmacologia , Regulação para Cima , Ratos Sprague-Dawley , Disfunção Cognitiva/metabolismo , Isquemia Encefálica/complicações , Aprendizagem em Labirinto/fisiologia , Hipocampo/metabolismo , MicroRNAs/metabolismo
8.
iScience ; 25(11): 105374, 2022 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-36388969

RESUMO

Energy harvesting technologies that convert fluid energy into usable electrical energy are of great significance, especially in long-distance pipeline systems. Here, in order to avoid the collision of conventional galloping triboelectric nanogenerators (GTENGs), and cause material damage or noise, a freestanding gallop-based triboelectric-piezoelectric hybrid nanogenerator (HG P-TENG) is proposed to reduce material wear and improve the reliability of GTENG. Two piezoelectric sheets are attached to the cantilever beam. The root-mean-square (RMS) and peak output power of the HG P-TENG are 68.9 µW and 1.27 mW, respectively. To improve the harvesting efficiency, the fixed copper electrodes are segmented, and experiments indicate that this way of segmenting electrodes can improve the energy harvesting efficiency. Finer electrodes can effectively increase the charging rate of capacitors. A self-powered thermohygrometer and light-emitting diodes (LEDs) are demonstrated in the wind tunnel. It demonstrates that the proposed hybrid nanogenerator will exhibit great potential in pipeline systems.

9.
Front Endocrinol (Lausanne) ; 13: 893506, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35966059

RESUMO

Objective: We aimed to evaluate the future outcomes of patients undergoing their first IVF (in vitro fertilization) attempt with no oocyte retrieved, no normal zygotes formed, or no embryos available for transfer and to identify factors affecting the live birth rate. Methods: Patients who underwent no transplantable embryo in their first IVF cycles but carried out several consecutive cycles between January 2012 to December 2020 were retrospectively enrolled and divided into three groups:group A (no egg retrieval), group B (no normal zygotes formed), and group C (no embryos available to transfer). The patients were also divided into the live birth group and non-live birth group according to whether they got a live baby or not. The clinical data and the cumulative clinical outcomes of groups were compared. Results: 496 patients met the inclusion criteria and enrolled, with 121 patients with no oocytes retrieved in group A, 138 patients with no normal zygotes formed in group B, and 237 patients with no embryos available to transfer in group C. The age [(34.75(5.82) vs 31.91(5.31), P<0.001; 34.75(5.82) vs 32.25(5.72), P<0.001)] and baseline FSH level [(13.04(8.82) vs 10.52(7.39), P=0.005; 13.04(8.82) vs 9.91(5.95), P<0.001)] of women in group A were significantly higher than those in groups B and C. The stable cumulative live birth rate/patient of three groups achieved 18.18% (after 5 cycles, group A), 28.98% (after 3 cycles, group B) and 20.25% (after 7 cycles, group C). Moreover, the multivariate regression analysis showed that female age and basic FSH were main factors affecting live birth outcome of patients with no embryo transfer in their first IVF cycle attempts. Conclusions: The future clinical outcome may be better in women with no normal zygotes than those with no oocyte retrieved or no available embryo at their first IVF cycle attempts. The main factors influencing the live birth are age and ovarian reserve.


Assuntos
Transferência Embrionária , Reserva Ovariana , Feminino , Fertilização in vitro , Hormônio Foliculoestimulante , Humanos , Estudos Retrospectivos
10.
Front Aging Neurosci ; 13: 760781, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34744697

RESUMO

Parkinson's disease (PD) is one of the most common neurodegenerative disorders. However, its cellular and molecular mechanisms still wrap in the mist. This is partially caused by the absence of appropriate animal models mimicking sporadic PD that constitutes the majority of cases. Previously, we reported that a cysteine protease, asparagine endopeptidase (AEP), is activated in an age-dependent manner, and cleaves α-synuclein in the brain of sporadic PD patients. The AEP-derived α-synuclein 1-103 fragment is required for the pathogenesis of PD. Thus, we designed and characterized a novel transgenic mouse line expressing α-synuclein 1-103 (designated N103 mice). This model shows an abundant accumulation of pathological α-synuclein in the central nervous system, loss of dopaminergic neurons in the substantia nigra, and progressive striatal synaptic degeneration. The N103 mice also manifest age-dependent PD-like behavioral impairments. Notably, the mice show weight loss and constipation, which are the common non-motor symptoms in PD. The RNA-sequencing analysis found that the transcriptomics pattern was extensively altered in N103 mice. In conclusion, the N103 mouse line, as a brand-new tool, might provide new insights into PD research.

11.
Colloids Surf B Biointerfaces ; 207: 111994, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34303996

RESUMO

In serval experimental researches, UV-induced hydrophilicity enabled better hemocompatibility in the TiO2 surface, which was considered to be caused by the removal of the carboxylic acid contamination from the surface. In this paper, we altered the surface wetting property by applying the formate contamination on the rutile (110) surface, and systematically investigated the adsorption properties of albumin and fibrinogen on hydrophilic/hydrophobic TiO2 surface. Unique contacts were found between the charged residues and the hydrophilic surface, anchoring the protein on the surface. The small size and the heart shape of albumin make it easy to cross the stable water layers near the surface. Besides, albumin has a higher proportion of charged residues, so it can form more unique contacts on the hydrophilic surface. Therefore, the albumin tends to adsorb on the hydrophilic surface. For the hydrophobic surface, the water layers near the surface are weakened, which helps the fibrinogen diffusing to the surface and adjusting its orientation. Although the hydrophobic surface cannot form the unique contacts, the larger size of fibrinogen can provide more residues to form enough ordinary contacts after adjusting, and then achieves stable adsorption. Therefore, fibrinogen tends to adsorb on the hydrophobic surface.


Assuntos
Fibrinogênio , Simulação de Dinâmica Molecular , Adsorção , Albuminas , Interações Hidrofóbicas e Hidrofílicas , Propriedades de Superfície , Titânio , Molhabilidade
12.
Neurobiol Dis ; 154: 105326, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33677035

RESUMO

Parkinson's disease (PD) is one of the most common neurodegenerative diseases, which is characterized by the loss of dopaminergic neurons in the nigrostriatal pathway. Synaptic dysfunction impairs dopamine turnover and contributes to the degeneration of dopaminergic neurons. However, the molecular mechanisms underlying synaptic dysfunction and dopaminergic neuronal vulnerability in PD are not clear. Here, we report that synaptojanin 1 (SYNJ1), a polyphosphoinositide phosphatase concentrated at nerve terminals, is a substrate of a cysteine proteinase, asparagine endopeptidase (AEP). SYNJ1 is cleaved by the cysteine proteinase AEP at N599 in the brains of PD patients. AEP-mediated cleavage of SYNJ1 disrupts neuronal phosphoinositide homeostasis and causes synaptic dysfunction. Overexpression of the AEP-generated fragments of SYNJ1 triggers synaptic dysfunction and the degeneration of dopaminergic neurons, inducing motor defects in the α-synuclein transgenic mice. Blockage of AEP-mediated cleavage of SYJN1 alleviates the pathological and behavioral defects in a mouse model of PD. Our results demonstrate that the fragmentation of SYNJ1 by AEP mediates synaptic dysfunction and dopaminergic neuronal degeneration in PD.


Assuntos
Cisteína Endopeptidases/metabolismo , Doença de Parkinson/metabolismo , Monoéster Fosfórico Hidrolases/metabolismo , Sinapses/metabolismo , Idoso , Animais , Células COS , Células Cultivadas , Chlorocebus aethiops , Potenciais Pós-Sinápticos Excitadores/fisiologia , Feminino , Células HEK293 , Humanos , Masculino , Camundongos , Camundongos da Linhagem 129 , Camundongos Endogâmicos C3H , Camundongos Knockout , Camundongos Transgênicos , Pessoa de Meia-Idade , Doença de Parkinson/genética , Doença de Parkinson/patologia , Monoéster Fosfórico Hidrolases/genética , Sinapses/patologia
13.
Aging (Albany NY) ; 13(7): 9522-9541, 2021 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-33539323

RESUMO

Chronic cerebral hypoperfusion (CCH) may lead to the cognitive dysfunction, but the underlying mechanisms are unclear. EGB761, extracted from Ginkgo biloba and as a phytomedicine widely used in the world, has been showed to have various neuroprotective roles and mechanisms, and therapeutic effects in Alzheimer's disease and other cognitive dysfunctions. However, improvements in cognitive function after CCH, following treatment with EGB761, have not been ascertained yet. In this study, we used the behavior test, electrophysiology, neurobiochemistry, and immunohistochemistry to investigate the EGB761's effect on CCH-induced cognitive dysfunction and identify its underlying mechanisms. The results showed that EGB761 ameliorates spatial cognitive dysfunction occurring after CCH. It may also improve impairment of the long-term potentiation, field excitable potential, synaptic transmission, and the transmission synchronization of neural circuit signals between the entorhinal cortex and hippocampal CA1. EGB761 may also reverse the inhibition of neural activity and the degeneration of dendritic spines and synaptic structure after CCH; it also prevents the downregulation of synaptic proteins molecules and pathways related to the formation and stability of dendritic spines structures. EGB761 may inhibit axon demyelination and ameliorate the inhibition of the mTOR signaling pathway after CCH to improve protein synthesis. In conclusion, EGB761 treatment after CCH may improve spatial cognitive function by ameliorating synaptic plasticity impairment, synapse degeneration, and axon demyelination by rectifying the inhibition of the mTOR signaling pathway.


Assuntos
Isquemia Encefálica/complicações , Disfunção Cognitiva/tratamento farmacológico , Ginkgo biloba , Plasticidade Neuronal/efeitos dos fármacos , Fármacos Neuroprotetores/uso terapêutico , Extratos Vegetais/uso terapêutico , Animais , Isquemia Encefálica/metabolismo , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/metabolismo , Espinhas Dendríticas/efeitos dos fármacos , Espinhas Dendríticas/metabolismo , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Fármacos Neuroprotetores/farmacologia , Extratos Vegetais/farmacologia , Ratos , Ratos Sprague-Dawley , Sinapses/efeitos dos fármacos , Sinapses/metabolismo
14.
Aging (Albany NY) ; 12(19): 19520-19538, 2020 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-33040050

RESUMO

Cognitive dysfunction caused by chronic cerebral hypoperfusion is a common underlying cause of many cognition-related neurodegenerative diseases. The mechanisms of cognitive dysfunction caused by CCH are not clear. Long non-coding RNA is involved in synaptic plasticity and cognitive function, but whether lncRNA is involved in cognitive dysfunction caused by CCH has not yet been reported. In the present study, we identified the altered lncRNAs and mRNAs by deep RNA sequencing. A total of 128 mRNAs and 91 lncRNAs were up-regulated, and 108 mRNAs and 98 lncRNAs were down-regulated. Real-time reverse transcription-polymerase chain reaction verified the reliability of the lncRNA and mRNA sequencing. Gene Ontology and KEGG pathway analyses showed that differentially-expressed mRNAs were related to peptide antigen binding, the extracellular space, the monocarboxylic acid transport, and tryptophan metabolism. The co-expression analysis showed that 161 differentially expressed lncRNAs were correlated with DE mRNAs. By predicting the miRNA in which both DE lncRNAs and DE mRNAs bind together, we constructed a competitive endogenous RNA network. In this lncRNAs-miRNAs-mRNAs network, 559 lncRNA-miRNA-mRNA targeted pairs were identified, including 83 lncRNAs, 67 miRNAs, and 108 mRNAs. Through GO and KEGG pathway analysis, we further analyzed and predicted the regulatory function and potential mechanism of ceRNA network regulation. Our results are helpful for understanding the pathogenesis of cognitive dysfunction caused by CCH and provide direction for further research.

15.
Brain Pathol ; 30(2): 392-404, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31747475

RESUMO

Recent studies have demonstrated that the brain is equipped with a lymphatic drainage system that is actively involved in parenchymal waste clearance, brain homeostasis and immune regulation. However, the exact anatomic drainage routes of brain lymph fluid (BLF) remain elusive, hampering the physiological study and clinical application of this system. In this study, we systematically dissected the anatomy of the BLF pathways in a rat model. Moreover, we developed a protocol to collect BLF from the afferent lymphatic vessels of deep cervical lymph nodes (dcLNs) and cerebrospinal fluid (CSF) from the fourth ventricle. Nuclear magnetic resonance spectroscopy showed that BLF contains more metabolites than CSF, suggesting that BLF might be a more sensitive indicator of brain dynamics under physiological and pathological conditions. Finally, we identified several metabolites as potential diagnostic biomarkers for glioma, Parkinson's disease and CNS infectious diseases. Together, these data may provide insight into the physiology of the lymphatic system in the brain and into the clinical diagnosis of CNS disorders.


Assuntos
Sistema Glinfático/anatomia & histologia , Sistema Glinfático/metabolismo , Animais , Encefalopatias/metabolismo , Encefalopatias/patologia , Masculino , Metaboloma , Ratos , Ratos Sprague-Dawley
16.
Neural Plast ; 2019: 2158285, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30923551

RESUMO

Chronic cerebral hypoperfusion (CCH) is a common pathophysiological mechanism that underlies cognitive decline and degenerative processes in dementia and other neurodegenerative diseases. Low cerebral blood flow (CBF) during CCH leads to disturbances in the homeostasis of hemodynamics and energy metabolism, which in turn results in oxidative stress, astroglia overactivation, and synaptic protein downregulation. These events contribute to synaptic plasticity and cognitive dysfunction after CCH. Tripchlorolide (TRC) is an herbal compound with potent neuroprotective effects. The potential of TRC to improve CCH-induced cognitive impairment has not yet been determined. In the current study, we employed behavioral techniques, electrophysiology, Western blotting, immunofluorescence, and Golgi staining to investigate the effect of TRC on spatial learning and memory impairment and on synaptic plasticity changes in rats after CCH. Our findings showed that TRC could rescue CCH-induced spatial learning and memory dysfunction and improve long-term potentiation (LTP) disorders. We also found that TRC could prevent CCH-induced reductions in N-methyl-D-aspartic acid receptor 2B, synapsin I, and postsynaptic density protein 95 levels. Moreover, TRC upregulated cAMP-response element binding protein, which is an important transcription factor for synaptic proteins. TRC also prevented the reduction in dendritic spine density that is caused by CCH. However, sham rats treated with TRC did not show any improvement in cognition. Because CCH causes disturbances in brain energy homeostasis, TRC therapy may resolve this instability by correcting a variety of cognitive-related signaling pathways. However, for the normal brain, TRC treatment led to neither disturbance nor improvement in neural plasticity. Additionally, this treatment neither impaired nor further improved cognition. In conclusion, we found that TRC can improve spatial learning and memory, enhance synaptic plasticity, upregulate the expression of some synaptic proteins, and increase the density of dendritic spines. Our findings suggest that TRC may be beneficial in the treatment of cognitive impairment induced by CCH.


Assuntos
Isquemia Encefálica/complicações , Disfunção Cognitiva/tratamento farmacológico , Diterpenos/uso terapêutico , Plasticidade Neuronal/efeitos dos fármacos , Fenantrenos/uso terapêutico , Aprendizagem Espacial/efeitos dos fármacos , Animais , Isquemia Encefálica/psicologia , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/psicologia , Espinhas Dendríticas/efeitos dos fármacos , Espinhas Dendríticas/fisiologia , Diterpenos/farmacologia , Hipocampo/efeitos dos fármacos , Hipocampo/fisiologia , Masculino , Plasticidade Neuronal/fisiologia , Fenantrenos/farmacologia , Ratos , Ratos Sprague-Dawley , Aprendizagem Espacial/fisiologia
17.
J Alzheimers Dis ; 66(4): 1559-1576, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30452417

RESUMO

Chronic cerebral hypoperfusion (CCH) affects the aging population and especially patients with neurodegenerative diseases, such as Alzheimer's disease or Parkinson's disease. CCH is closely related to the cognitive dysfunction in these diseases. Glucagon-like peptide-2 receptor (GLP2R) mRNA and protein are highly expressed in the gut and in hippocampal neurons. This receptor is involved in the regulation of food intake and the control of energy balance and glucose homeostasis. The present study employed behavioral techniques, electrophysiology, western blotting, immunohistochemistry, quantitative real time polymerase chain reaction (qRT-PCR), and Golgi staining to investigate whether the expression of GLP2R changes after CCH and whether GLP2R is involved in cognitive impairment caused by CCH. Our findings show that CCH significantly decreased hippocampal GLP2R mRNA and protein levels. GLP2R upregulation could prevent CCH-induced cognitive impairment. It also improved the CCH-induced impairment of long-term potentiation and long-term depression. Additionally, GLP2R modulated after CCH the AKT-mTOR-p70S6K pathway in the hippocampus. Moreover, an upregulation of the GLP2R increased the neurogenesis in the dentate gyrus, neuronal activity, and density of dendritic spines and mushroom spines in hippocampal neurons. Our findings reveal the involvement of GLP2R via a modulation of the AKT-mTOR-p70S6K pathway in the mechanisms underlying CCH-induced impairments of spatial learning and memory. We suggest that the GLP2R and the AKT-mTOR-p70S6K pathway in the hippocampus are promising targets to treat cognition deficits in CCH.


Assuntos
Isquemia Encefálica/metabolismo , Receptor do Peptídeo Semelhante ao Glucagon 2/metabolismo , Hipocampo/metabolismo , Aprendizagem Espacial/fisiologia , Memória Espacial/fisiologia , Animais , Isquemia Encefálica/fisiopatologia , Espinhas Dendríticas/metabolismo , Modelos Animais de Doenças , Masculino , Plasticidade Neuronal/fisiologia , Neurônios/metabolismo , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/fisiologia , Serina-Treonina Quinases TOR/metabolismo , Regulação para Cima
18.
Neurochem Res ; 43(4): 806-820, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29392519

RESUMO

Neuroinflammation and oxidative stress play an important role in cognition deficit following chronic cerebral hypoperfusion (CCH). Luteolin, a natural flavonoid found in many plants, is known for a variety of pharmacological activities, such as its anti-inflammatory, anti-allergy, urate, anti-tumor, antibacterial, and antiviral effects. To assess whether luteolin could prevent CCH-induced cognitive dysfunction, through its anti-inflammatory and anti-oxidative-stress effects, we used enzyme-linked immunosorbent assays, enzyme activity assays, behavioral methods, immunohistochemistry, and electrophysiology to detect neuroinflammation and oxidative stress, cognition alterations, and long-term potential (LTP), in a bilateral common carotid arteries ligation (2VO) rat model. We demonstrated that CCH increased tumor necrosis factor α (TNF-α), interleukin 1ß (IL-1ß), interleukin 6 (IL-6), and malondialdehyde (MDA), and decreased superoxide dismutase (SOD) and glutathione peroxidase (GPx) levels. Further, it caused microglia over-activation and astrogliosis, learning and short-term memory dysfunction, and an LTP deficit. Luteolin treatment reversed CCH-induced changes. Specifically, luteolin prevented the increase of TNF-α and IL-1ß, IL-6, and MDA, improved the activity of SOD and GPx, inhibited microglia over-activation and astrogliosis (particularly in the hippocampus and cortex), and ameliorated learning and short-term memory dysfunction, and LTP deficit. Thus, our study suggested that luteolin could be a preferable anti-inflammatory agent to protect cognitive function and synaptic plasticity following CCH. Luteolin could also be putative therapeutic candidate for other inflammation-related brain diseases.


Assuntos
Anti-Inflamatórios/uso terapêutico , Disfunção Cognitiva/tratamento farmacológico , Disfunção Cognitiva/metabolismo , Mediadores da Inflamação/antagonistas & inibidores , Mediadores da Inflamação/metabolismo , Luteolina/uso terapêutico , Animais , Anti-Inflamatórios/farmacologia , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/metabolismo , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Interleucina-1beta/antagonistas & inibidores , Interleucina-1beta/metabolismo , Luteolina/farmacologia , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Aprendizagem em Labirinto/fisiologia , Ratos , Ratos Sprague-Dawley , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Fator de Necrose Tumoral alfa/metabolismo
19.
Curr Neurovasc Res ; 14(4): 385-396, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29090669

RESUMO

BACKGROUND: Chronic Cerebral Hypoperfusion (CCH) is an important vascular risk factor for vascular-related dementia cognitive impairment and there are no effective measures for the prevention and treatment of cognitive deficit by CCH and the underlying mechanisms are still poorly understood. Methyl cytidine-phosphate-guanosine (CpG) binding protein 2 (MeCP2), regulated by microRNA 132 (miR-132), is as a transcriptional repressor in high concentrations in the brain, which regulates the expression of synaptic proteins and neuroplasticity, and may be involved in the cognitive deficit after CCH. But no relevant studies have been reported. The aim of this study is to investigate the status of MeCP2 expression after CCH and explore whether MeCP2 changes is associated with cognitive deficits after CCH. METHODS: We investigated MeCP2 expression after CCH using Western blotting, quantitative Real- Time Polymerase Chain Reaction (qRT-PCR) analysis and immunofluorescence technique in a rat model of permanent bilateral common carotid artery occlusion (2VO) to mimic CCH. We determined the effect of MeCP2 expression on cognitive deficits and neuroplasticity after CCH through lenti-virus stereotaxic injection, the Morris water maze and electrophysiology. RESULTS: CCH contributed to the down-regulation of MeCP2 and mecp2 expressions in the hippocampus and cortex. miR-132 up-regulated by 2VO was distinctly negatively correlated with MeCP2 down-regulation by miR-132 inhibitors. MeCP2 over-expression improved learning and memory impairment, as well as neuroplasticity after 2VO. Brain-Derived Neurotrophic Factor (BDNF) and the activities of its downstream pathways moleculars, tropomyosin receptor kinase B (TrkB) and the cAMP Response Element Binding Protein (CREB) were down-regulated by 2VO and rescued by MeCP2 over-expression. CONCLUSION: Our study found that miR-132 may participate in the down-regulation of MeCP2 after CCH and MeCP2 down-regulation was possibly involved in the cognitive deficit through regulation of BDNF and its downstream pathways after 2VO. Our findings expounded the underlying mechanisms of cognition deficit after CCH, which contributes to understanding the mechanisms of vascular dementia.


Assuntos
Circulação Cerebrovascular/fisiologia , Transtornos Cerebrovasculares/metabolismo , Disfunção Cognitiva/metabolismo , Regulação para Baixo/fisiologia , Proteína 2 de Ligação a Metil-CpG/metabolismo , MicroRNAs/biossíntese , Animais , Transtornos Cerebrovasculares/complicações , Doença Crônica , Disfunção Cognitiva/etiologia , Masculino , Aprendizagem em Labirinto/fisiologia , Proteína 2 de Ligação a Metil-CpG/antagonistas & inibidores , Ratos , Ratos Sprague-Dawley
20.
Phys Rev E ; 94(5-1): 053117, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27967180

RESUMO

Flow in a rectangular channel with superhydrophobic (SH) top and bottom walls was investigated experimentally. Different SH surfaces, including hierarchical structured surfaces and surfaces with different micropost sizes (width and spacing) but the same solid fraction, were fabricated and measured. Pressure loss and flow rate in the channel with SH top and bottom walls were measured, with Reynolds number changing from 700 to 4700, and the corresponding friction factor for the SH surface was calculated. The statuses of the air plastron on different SH surfaces were observed during the experiment. In our experiment, compared with the experiment for the smooth surface, drag reductions were observed for all SH surfaces, with the largest drag reduction of 42.2%. It was found that the hierarchy of the microstructure can increase the drag reduction by decreasing the solid fraction and enhancing the stability of the air-water interface. With a fixed solid fraction, the drag reduction decreases as the post size (width and spacing) increases, due to the increasing curvature and instability effects of the air-water interface. A correlation parameter between the contact angle hysteresis, the air-water interface stability, and the drag reduction of the SH surfaces was found.

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