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1.
Front Pharmacol ; 13: 940999, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35935875

RESUMO

Alzheimer's disease (AD) is a neurodegenerative disease characterized by memory loss and cognitive dysfunction in the elderly, with amyloid-beta (Aß) deposition and hyperphosphorylation of tau protein as the main pathological feature. Nuclear factor 2 (Nrf2) is a transcription factor that primarily exists in the cytosol of hippocampal neurons, and it is considered as an important regulator of autophagy, oxidative stress, and inflammation. Total saikosaponins (TS) is the main bioactive component of Radix bupleuri (Chaihu). In this study, it was found that TS could ameliorate cognitive dysfunction in APP/PS1 transgenic mice and reduce Aß generation and senile plaque deposition via activating Nrf2 and downregulating the expression of ß-secretase 1 (BACE1). In addition, TS can enhance autophagy by promoting the expression of Beclin-1 and LC3-II, increasing the degradation of p62 and NDP52 and the clearance of phosphorylated tau (p-tau), and reducing the expression of p-tau. It can also downregulate the expression of nuclear factor-κB (NF-κB) to inhibit the activation of glial cells and reduce the release of inflammatory factors. In vitro experiments using PC12 cells induced by Aß, TS could significantly inhibit the aggregation of Aß and reduce cytotoxicity. It was found that Nrf2 knock-out weakened the inhibitory effect of TS on BACE1 and NF-κB transcription in PC12 cells. Moreover, the inhibitory effect of TS on BACE1 transcription was achieved by promoting the binding of Nrf2 and the promoter of BACE1 ARE1. Results showed that TS downregulated the expression of BACE1 and NF-κB through Nrf2, thereby reducing the generation of Aß and inhibiting neuroinflammation. Furthermore, TS can ameliorate synaptic loss and alleviate oxidative stress. In gut microbiota analysis, dysbiosis was demonstrated in APP/PS1 transgenic mice, indicating a potential link between gut microbiota and AD. Furthermore, TS treatment reverses the gut microbiota disorder in APP/PS1 mice, suggesting a therapeutic strategy by remodeling the gut microbe. Collectively, these data shows that TS may serve as a potential approach for AD treatment. Further investigation is needed to clarify the detailed mechanisms underlying TS regulating gut microbiota and oxidative stress.

2.
Transl Neurodegener ; 10(1): 27, 2021 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-34372927

RESUMO

Alzheimer's disease (AD) is a neurodegenerative disease that currently cannot be cured by any drug or intervention, due to its complicated pathogenesis. Current animal and cellular models of AD are unable to meet research needs for AD. However, recent three-dimensional (3D) cerebral organoid models derived from human stem cells have provided a new tool to study molecular mechanisms and pharmaceutical developments of AD. In this review, we discuss the advantages and key limitations of the AD cerebral organoid system in comparison to the commonly used AD models, and propose possible solutions, in order to improve their application in AD research. Ethical concerns associated with human cerebral organoids are also discussed. We also summarize future directions of studies that will improve the cerebral organoid system to better model the pathological events observed in AD brains.


Assuntos
Doença de Alzheimer/patologia , Pesquisa Biomédica/tendências , Encéfalo/patologia , Modelos Biológicos , Organoides/patologia , Doença de Alzheimer/metabolismo , Animais , Pesquisa Biomédica/métodos , Encéfalo/metabolismo , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Células-Tronco Pluripotentes Induzidas/patologia , Organoides/metabolismo , Dobramento de Proteína
3.
Biol Pharm Bull ; 44(11): 1688-1696, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34433707

RESUMO

Microglial activation and neuroinflammation induced by amyloid ß (Aß) play pivotal roles in Alzheimer's disease (AD) pathogenesis. Astragaloside IV (AS-IV) is one of the major active compounds of the traditional Chinese medicine Astmgali Radix. It has been reported that AS-IV could protect against Aß-induced neuroinflammation and cognitive impairment, but the underlying mechanisms need to be further clarified. In this study, the therapeutic effects of AS-IV were investigated in an oligomeric Aß (oAß) induced AD mice model. The effects of AS-IV on microglial activation, neuronal damage and reduced nicotinamide adenine dinucleotide phosphate (NADPH) oxidase expression were further studied. Different doses of AS-IV were administered intragastrically once a day after intracerebroventricularly oAß injection. Results of behavioral experiments including novel object recognition (NOR) test and Morris water maze (MWM) test revealed that AS-IV administration could significantly ameliorate oAß-induced cognitive impairment in a dose dependent manner. Enzyme linked immunosorbent assay (ELISA) results showed that increased levels of reactive oxygen species (ROS), tumor necrosis factor α (TNF-α), interleukin-1ß (IL-1ß) and IL-6 in hippocampal tissues induced by oAß injection were remarkably inhibited after AS-IV treatment. OAß induced microglial activation and neuronal damage was significantly suppressed in AS-IV-treated mice brain, observed in immunohistochemistry results. Furthermore, oAß upregulated protein expression of NADPH oxidase subunits gp91phox, p47phox, p22phox and p67phox were remarkably reduced by AS-IV in Western blotting assay. These results revealed that AS-IV could ameliorate oAß-induced cognitive impairment, neuroinflammation and neuronal damage, which were possibly mediated by inhibition of microglial activation and down-regulation of NADPH oxidase protein expression. Our findings provide new insights of AS-IV for the treatment of neuroinflammation related diseases such as AD.


Assuntos
Doença de Alzheimer , Astrágalo/química , Disfunção Cognitiva , Microglia/efeitos dos fármacos , NADPH Oxidases/metabolismo , Doenças Neuroinflamatórias , Saponinas/farmacologia , Triterpenos/farmacologia , Doença de Alzheimer/induzido quimicamente , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/efeitos adversos , Animais , Disfunção Cognitiva/tratamento farmacológico , Disfunção Cognitiva/metabolismo , Citocinas/metabolismo , Modelos Animais de Doenças , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , Hipocampo/citologia , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Masculino , Aprendizagem em Labirinto , Camundongos Endogâmicos ICR , NADP , Doenças Neuroinflamatórias/tratamento farmacológico , Doenças Neuroinflamatórias/metabolismo , Neurônios , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Fitoterapia , Espécies Reativas de Oxigênio/metabolismo , Saponinas/uso terapêutico , Triterpenos/uso terapêutico
4.
Journal of Experimental Hematology ; (6): 1272-1277, 2020.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-827127

RESUMO

OBJECTIVE@#To explore the renal pathology and cytogenetic features in the multiple myeloma (MM) patients with renal impairment.@*METHODS@#The clinical data of newly diagnosed MM patients with renal impairment in our hospital from January 2009 to January 2019 were analyzed retrospectively, and the relationship between FISH results and results of renal pathological exanimation was analyzed statistically by using SPSS 20.0.@*RESULTS@#A total of 20 patients underwent renal biopsy, included 12 males and 8 females. FISH result showed that out of 20 patients, 7 cases presented interstitial nephritis, among which 3 cases were negative for FISH, and in the remaining cases the rate of IgH rearrangement, 1q21 amplification, RB1 deletion, D13S319 deletion, and P53 deletion detection was 42.86%, 28.57%, 28.57%, 28.57% and 14.29% respectively, the detection positive rate was statistically significantly lower as compared with total probe positive rate (P<0.01). There were 6 cases of cast nephropathy, among which IgH rearrangement, the rate of 1q21 amplification, RB1 deletion, D13S319 deletion, and P53 deletion detection was 66.67%, 50%, 66.67%, 50% and 0% respectively. Compared with the total probe positive rate, there was no statistical significance (P>0.05). There were 4 cases of acute tubular necrosis, among which the detection rates of IgH rearrangement, 1q21 amplification, RB1 deletion, D13S319 deletion, and P53 deletion was 100%, 50%, 50%, 25% and 25%, respectively. Compared with the total probe positive rate, there was no statistical significance (P>0.05). There were one case of amyloidosis, and one case of tubular nephropathy with amyloidosis, the detection with 5 probes were all positive. One case of light chain deposition disease was positive for RB1 gene deletion + D13S319 gene deletion.@*CONCLUSION@#FISH in the MM patients with different renal pathological changes is characterized by heterogeneity, which can be used to predict the risk of renal damage and speculate possible renal pathological types to guide prognosis.


Assuntos
Feminino , Humanos , Masculino , Aberrações Cromossômicas , Análise Citogenética , Citogenética , Hibridização in Situ Fluorescente , Mieloma Múltiplo , Estudos Retrospectivos
5.
Chem Commun (Camb) ; 55(62): 9144-9147, 2019 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-31304482

RESUMO

The phosphine-catalyzed asymmetric dearomative [3+2] cycloaddition of 2-nitrobenzofurans with aldehyde-derived Morita-Baylis-Hillman (MBH) carbonates or allenoate was developed. The reaction with MBH carbonates resulted in a series of cyclopentabenzofurans containing three contiguous stereocenters with good to high yields, diastereoselectivities and enantioselectivities. The use of allenoate also gave the target product with moderate enantioselectivity.

6.
Chem Commun (Camb) ; 55(4): 553-556, 2019 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-30556555

RESUMO

Intermolecular asymmetric dearomative 1,3-dipolar cycloaddition of 2-nitrobenzofurans with azomethine ylides was enabled by using a chiral Cu(i)/(S,Sp)-iPr-Phosferrox catalyst. As a result, a series of highly stereoselective chiral [2,3]-fused hydrobenzofurans possessing four contiguous stereogenic centers were obtained with good to high yields, diastereoselectivities and enantioselectivities. The reaction has broad substrate scope tolerating various functional groups.

7.
Journal of Experimental Hematology ; (6): 1402-1408, 2019.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-775707

RESUMO

OBJECTIVE@#To investigate the mechanism of rapamycin-induced apoptosis of chronic myelogenous leukemia cells.@*METHODS@#The chronic granulocytic leukemia K562 cells were divided into 3 groups: A, B and C group were treated with rapamycin of 10, 15 and 20 nmol/L, repectively for 24 h, while the K562 cells in control group were not treated with rapamycin. The effect of rapamycin on the proliferation of K562 cells was detected by MTT, and the effect of rapamycin on the apoptosis of K562 cells was detected by AnnexinV-FITC/PI double staining. The expression level of EZH2/Hedgehog signaling pathway genes in K562 cells was detected by RT-PCR, and Western blot was used to detect the levels of apoptotic protein and the related signaling pathway proteins in K562 cells.@*RESULTS@#The MTT assay showed that the different concentration of rapamycin had obvious inhibitory effects on the cells, and the survival rate of cells in group C was 37.6%±3.4%, which was significantly lower than that of the other groups (P<0.05). The apoptosis rate of cells in group C was 93.1%±8.1%, which was significantly higher than that of the other groups (P<0.05). By Western blot, it was found that the relative expression levels of Caspase-3 and BAX protein in group C were 0.36 ± 0.04 and 0.39±0.06, respectively, which were significantly higher than those in other groups (P<0.05), and the level of BCL-2 protein was 0.17±0.03, which was significantly lower than that of other groups (P<0.05). By RT-PCR, it was found that the mRNA levels of EZH2 and Hedgehog genes in A, B and C groups were significantly lower than those in the control group (P<0.05), but mRNA level of Ptch1 gene was significantly higher than that of the control (P<0.05). By Western blot, it was found that the expression levels of EZH2 and Hedgehog protein in A, B and C groups were significantly lower than that in the control group (P<0.05), but the level of Ptch1 protein was higher than that of the control (P<0.05). The relative levels of EZH2 and Hedgehog protein in group C were 0.21 ±0.03 and 0.16±0.05 respectively, which were significantly lower than those in other groups (P<0.05), and Ptch1 protein level were 0.46 ±0.06, significantly higher than that of other groups (P<0.05).@*CONCLUSION@#Rapamycin can inhibit the protein expression of EZH2 in leukemic cells, thus interfere with the activation of Hedgehog signaling pathway, promote the expression of apoptotic protein, reduce the level of anti apoptotic protein, and eventually induce apoptosis of leukemia cells.


Assuntos
Humanos , Apoptose , Proliferação de Células , Proteína Potenciadora do Homólogo 2 de Zeste , Proteínas Hedgehog , Células K562 , Transdução de Sinais , Sirolimo
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