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1.
J Ethnopharmacol ; 322: 117628, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38158101

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Piper longum L., a medicinal and food homologous herb, has a traditional history of use in treating gastrointestinal and neurological disorders. Piperine (PIP) the main alkaloid of P. longum, exists neuroprotective effects on various animal models of Parkinson's disease (PD). Nevertheless, the underlying mechanism, particularly the role of PIP in promoting gut-brain autophagy for α-Synuclein (α-Syn) degradation in PD, remains incompletely understood. AIM OF THE STUDY: To explore the role of PIP in regulating the gut-brain autophagy signaling pathway to reduce α-Syn levels in both the colon and substantia nigra (SN) of PD model rats. MATERIALS AND METHODS: Behavioral experiments were conducted to assess the impact of PIP on 6-hydroxydopamine (6-OHDA)-induced PD rats. The intestinal microbiome composition and intestinal metabolites were analyzed by metagenomics and GC-MS/MS. The auto-phagosomes were visualized by transmission electron microscopy. Immunohistochemistry, immunofluorescence, and western blotting were performed to assess the levels of tyrosine hydroxylase (TH), α-Syn, LC3II/LC3I, p62, and the PI3K/AKT/mTOR pathway in both the SN and colon of the rats. The pathway-related inhibitor and agonist were used to verify the autophagy mechanism in the SH-SY5Y cells overexpressing A53T mutant α-Syn (A53T-α-Syn). RESULTS: PIP improved autonomic movement and gastrointestinal dysfunctions, reduced α-Syn aggregation and attenuated the loss of dopaminergic neurons in 6-OHDA-induced PD rats. After oral administration of PIP, the radio of LC3II/LC3I increased and the expression of p62 was degraded, as well as the phosphorylation levels of PI3K, AKT and mTOR decreased in the SN and colon of rats. The effect of PIP on reducing A53T-α-Syn through the activation of the PI3K/AKT/mTOR-mediated autophagy pathway was further confirmed in A53T-α-Syn transgenic SH-SY5Y cells. This effect could be inhibited by the autophagy inhibitor bafilomycin A1 and the PI3K agonist 740 Y-P. CONCLUSIONS: Our findings suggested that PIP could protect neurons by activating autophagy to degrade α-Syn in the SN and colon, which were related to the suppression of PIP on the activation of PI3K/AKT/mTOR signaling pathway.


Assuntos
Alcaloides , Benzodioxóis , Neuroblastoma , Doença de Parkinson , Piperidinas , Alcamidas Poli-Insaturadas , Ratos , Humanos , Animais , Doença de Parkinson/tratamento farmacológico , alfa-Sinucleína/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Oxidopamina , Espectrometria de Massas em Tandem , Alcaloides/farmacologia , Alcaloides/uso terapêutico , Serina-Treonina Quinases TOR/metabolismo , Encéfalo/metabolismo , Autofagia
2.
Front Nutr ; 8: 664976, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34712684

RESUMO

White kidney beans contain α-amylase inhibitors that can be used in diet for weight reduction. In this study, we investigated the potential of white kidney bean (phaseolus vulgaris L.) extract enriched in α-amylase inhibitor as a food additive in yogurt to regulate blood glucose in hyperglycemic animals. Five groups of C57BL/6J mice were fed for 8 weeks with standard chow diets, high-fat diets (HFD), or high-fat diets with supplement of α-amylase inhibitor in white kidney beans (P. vulgaris extract, PVE), yogurt (Y), and PVE added yogurt (YPVE), respectively. The HFD weakened glucose tolerance and caused insulin resistance in mice, and changed the characteristics of intestinal flora. The intervention of Y, PVE, and YPVE decreased blood glucose, insulin, hyperlipidemia, and inflammatory cytokine levels in mice fed with HFD. Moreover, the YPVE could regulate the components of host intestinal microbiota toward a healthy pattern, significantly increased the metabolic-related flora Corynebacterium, Granulicatella, and Streptococcus, while it decreased Paraprevotella and Allobaculum. Thus, YPVE markedly increased functions of "Amino Acid Metabolism," "Energy Metabolism," "Nucleotide Metabolism," and declined functions of "Glycan Biosynthesis and Metabolism." Consequently, YPVE could be developed as a new functional food because of its beneficial prebiotic properties in the metabolic syndrome.

3.
Front Cell Dev Biol ; 9: 687912, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34222256

RESUMO

MicroRNAs in small extracellular vesicle (sEV-miRNAs) have been widely investigated as crucial regulated molecules secreted by tumor cells to communicate with surroundings. It is of great significance to explore the loading mechanism of sEV-miRNAs by tumor cells. Here, we comprehensively illustrated a reasoned loading pathway of batched tumor-promoting sEV-miRNAs in non-small cell lung cancer (NSCLC) cell line A549 with the application of a multi-omics method. The protein heterogeneous nuclear ribonucleoprotein A1 (hnRNPA1) was strictly selected as a powerful sEV-miRNA loading protein from miRNA-binding proteome and further verified through small RNA sequencing after hnRNPA1 silence. In terms of the mechanism, SUMOylated hnRNPA1 in sEVs was verified to control sEV-miRNA loading. Subsequently, as a scaffolding component of caveolae, caveolin-1 (CAV1) was detailedly demonstrated to assist the loading of SUMOylated hnRNPA1 and its binding miRNAs into sEVs. Inhibition of CAV1 significantly prevented SUMOylated hnRNPA1 from encapsulating into sEVs, resulting in less enrichment of sEV-miRNAs it loaded. Finally, we confirmed that hnRNPA1-loaded sEV-miRNAs could facilitate tumor proliferation and migration based on database analysis and cytological experiments. Our findings reveal a loading mechanism of batched tumor-promoting sEV-miRNAs, which may contribute to the selection of therapeutic targets for lung cancer.

4.
Cell Death Dis ; 12(7): 702, 2021 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-34262023

RESUMO

Acquired resistance to glucocorticoids (GCs) is an obstacle to the effective treatment of leukemia, but the molecular mechanisms of steroid insensitivity have not been fully elucidated. In this study, we established an acquired GC-resistant leukemia cell model and found a long noncoding RNA, HOTAIRM1, was overexpressed in the resistant cells by transcriptional profiling, and was higher expressed in patients with poor prognosis. The whole-genome-binding sites of HOTAIRM1 were determined by ChIRP-seq (chromatin isolation by RNA purification combined with sequencing) analysis. Further study determined that HOTAIRM1 bound to the transcriptional inhibitory region of ARHGAP18 and repressed the expression of ARHGAP18, which led to the increase of RHOA/ROCK1 signaling pathway and promoted GC resistance through antiapoptosis of leukemia cells. The inhibition of ROCK1 in GC-resistant cells could restore GCs responsiveness. In addition, HOTAIRM1 could also act as a protein sequester to prevent transcription factor AML1(acute myeloid leukemia 1) from binding to the regulatory region of ARHGAP18 by interacting with AML1. At last, we also proved AML1 could directly activate the expression of HOTAIRM1 through binding to the promoter of HOTAIRM1, which enriched the knowledge on the regulation of lncRNAs. This study revealed epigenetic causes of glucocorticoid resistance from the perspective of lncRNA, and laid a foundation for the optimization of glucocorticoid-based leukemia treatment strategy in clinic.


Assuntos
Antineoplásicos/farmacologia , Subunidade alfa 2 de Fator de Ligação ao Core/metabolismo , Dexametasona/farmacologia , Resistencia a Medicamentos Antineoplásicos , Proteínas Ativadoras de GTPase/metabolismo , Glucocorticoides/farmacologia , Leucemia/tratamento farmacológico , MicroRNAs/metabolismo , Quinases Associadas a rho/metabolismo , Proteína rhoA de Ligação ao GTP/metabolismo , Apoptose/efeitos dos fármacos , Sítios de Ligação , Linhagem Celular Tumoral , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Resistencia a Medicamentos Antineoplásicos/genética , Proteínas Ativadoras de GTPase/genética , Regulação Leucêmica da Expressão Gênica , Células HEK293 , Humanos , Leucemia/enzimologia , Leucemia/genética , Leucemia/patologia , MicroRNAs/genética , Ligação Proteica , Transdução de Sinais , Quinases Associadas a rho/genética , Proteína rhoA de Ligação ao GTP/genética
5.
Genes (Basel) ; 12(5)2021 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-33922442

RESUMO

Hematopoietic differentiation is a well-orchestrated process by many regulators such as transcription factor and long non-coding RNAs (lncRNAs). However, due to the large number of lncRNAs and the difficulty in determining their roles, the study of lncRNAs is a considerable challenge in hematopoietic differentiation. Here, through gene co-expression network analysis over RNA-seq data generated from representative types of mouse myeloid cells, we obtained a catalog of potential key lncRNAs in the context of mouse myeloid differentiation. Then, employing a widely used in vitro cell model, we screened a novel lncRNA, named Gdal1 (Granulocytic differentiation associated lncRNA 1), from this list and demonstrated that Gdal1 was required for granulocytic differentiation. Furthermore, knockdown of Cebpe, a principal transcription factor of granulocytic differentiation regulation, led to down-regulation of Gdal1, but not vice versa. In addition, expression of genes involved in myeloid differentiation and its regulation, such as Cebpa, were influenced in Gdal1 knockdown cells with differentiation blockage. We thus systematically identified myeloid differentiation associated lncRNAs and substantiated the identification by investigation of one of these lncRNAs on cellular phenotype and gene regulation levels. This study promotes our understanding of the regulation of myeloid differentiation and the characterization of roles of lncRNAs in hematopoietic system.


Assuntos
Hematopoese , Células Mieloides/metabolismo , RNA Longo não Codificante/genética , Transcriptoma , Animais , Proteínas Estimuladoras de Ligação a CCAAT/genética , Proteínas Estimuladoras de Ligação a CCAAT/metabolismo , Linhagem Celular , Camundongos , Células Mieloides/citologia , RNA Longo não Codificante/metabolismo
6.
Proc Natl Acad Sci U S A ; 118(14)2021 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-33782126

RESUMO

microRNA-218 (miR-218) has been linked to several cognition related neurodegenerative and neuropsychiatric disorders. However, whether miR-218 plays a direct role in cognitive functions remains unknown. Here, using the miR-218 knockout (KO) mouse model and the sponge/overexpression approaches, we showed that miR-218-2 but not miR-218-1 could bidirectionally regulate the contextual and spatial memory in the mice. Furthermore, miR-218-2 deficiency induced deficits in the morphology and presynaptic neurotransmitter release in the hippocampus to impair the long term potentiation. Combining the RNA sequencing analysis and luciferase reporter assay, we identified complement component 3 (C3) as a main target gene of miR-218 in the hippocampus to regulate the presynaptic functions. Finally, we showed that restoring the C3 activity in the miR-218-2 KO mice could rescue the synaptic and learning deficits. Therefore, miR-218-2 played an important role in the cognitive functions of mice through C3, which can be a mechanism for the defective cognition of miR-218 related neuronal disorders.


Assuntos
Complemento C3/genética , Hipocampo/metabolismo , Potenciação de Longa Duração , MicroRNAs/metabolismo , Vesículas Sinápticas/metabolismo , Regiões 3' não Traduzidas , Animais , Células Cultivadas , Complemento C3/metabolismo , Exocitose , Hipocampo/citologia , Hipocampo/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/genética , Neurônios/metabolismo , Neurônios/fisiologia
7.
Small ; 17(4): e2004750, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33373110

RESUMO

Molecules involved in crosstalk between tumor cells and fibroblasts play vital roles in tumor progression. Extracellular matrix proteins, whose abundance is altered after being affected by tumor-derived exosomes, possess considerable promise as biomarkers for diagnosis or prognosis. In this study, quantitative proteomics is employed to determine the abundance of proteins secreted by normal fibroblasts and exosome-activated fibroblasts, which first identify differentially secreted proteins affected by lung cancer cell-derived exosomes. Based on the differentially secreted proteins and multiple independent datasets comprising 1897 patient samples with non-small cell lung carcinoma or other lung diseases, a diagnostic marker is identified that can effectively distinguish tumor tissues from normal tissue, as well as tumor-associated stroma from normal stroma, and a five-gene prognostic signature is presented with independent prognostic impact to identify patients who may require further adjuvant therapy after surgical resection. In addition, the secretome provides novel potential targets for clinical treatment.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Exossomos , Neoplasias Pulmonares , Biomarcadores , Biomarcadores Tumorais , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Fibroblastos , Humanos , Neoplasias Pulmonares/diagnóstico
8.
Sci Total Environ ; 762: 143058, 2021 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-33127154

RESUMO

The avian colibacillosis outbreak is a disease that threatens public health, poultry production, and economic interests, even after antibiotic feed addition. It is known that avian pathogenic E. coli is a major pathogenic factor; however, the systemic characteristics of gut flora in disease samples and how pathogens grow remain unknown. To study these issues in depth, we used the whole microbial genome shotgun sequencing technique to compare entire microbes in diseased and healthy broiler chickens. We found that it was not only E. coli that increased substantially, but most pathogenic flora also increased significantly in diseased samples. Subsequently, we proved that aminoglycoside antibiotic resistance genes were mainly found in non-E. coli strains. This suggests that E. coli survival under antibiotic stress was due to the cooperative resistance from non-E. coli strains. Among all these increasing strains, attaching and effacing pathogens could damage host intestinal epithelial cells to release oxygen in the gut to make the microenvironment more adaptable for E. coli strains. Furthermore, we observed that the functions of the T4SS/T6SS secretion system were dramatically enhanced, which could help E. coli to compete and enlarge their living spaces. Ultimately, pathogenic E. coli accumulated to cause avian colibacillosis. This study provides a new insight into intestinal microecology in diseased individuals, which would propose new treatment options for avian colibacillosis from a metagenome perspective.


Assuntos
Microbioma Gastrointestinal , Doenças das Aves Domésticas , Animais , Antibacterianos , Galinhas , Escherichia coli , Humanos , Virulência
9.
Microorganisms ; 8(10)2020 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-33050530

RESUMO

Whole metagenome shotgun sequencing is a powerful approach to detect the functional potential of microbial communities. Currently, the read-based metagenomics profiling for established database (RBED) method is one of the two kinds of conventional methods for species and functional annotations. However, the databases, which are established based on test samples or specific reference genomes or protein sequences, limit the coverage of global microbial diversity. The other assembly-based metagenomics profiling for unestablished database (ABUD) method has a low utilization rate of reads, resulting in a lot of biological information loss. In this study, we proposed a new method, read-based metagenomics profiling for unestablished database (RBUD), based on Metagenome Database of Global Microorganisms (MDGM), to solve the above problems. To evaluate the accuracy and effectiveness of our method, the intestinal bacterial composition and function analyses were performed in both avian colibacillosis chicken cases and type 2 diabetes mellitus patients. Comparing to the existing methods, RBUD is superior in detecting proteins, percentage of reads mapping and ontological similarity of intestinal microbes. The results of RBUD are in better agreement with the classical functional studies on these two diseases. RBUD also has the advantages of fast analysis speed and is not limited by the sample size.

10.
Comput Struct Biotechnol J ; 18: 2326-2335, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32994891

RESUMO

Single-cell genomics has advanced rapidly as trace-DNA amplification technologies evolved. However, current technologies are subject to a variety of pitfalls such as contamination, uneven genomic coverage, and amplification errors. Even for the "golden" strategy of single stem cell-derived clonal formation, high-fidelity amplification is applicable merely to single stem cells. It's still challenging to accurately define somatic mutations of a single cell in various cell types. Herein, we provided evidence, for the first time, to prove that induced pluripotent stem cells (iPS cells or iPSC), being a single somatic cell-derived clone, are recording almost identical (>90%) mutational profile of the initial cell progenitor. This finding demonstrates iPS technique, applicable to any cell type, can be utilized as a cell cloning strategy favorable for single-cell genomic amplification. This novel strategy is not limited by cell-type constraints or amplification artifacts, and thus enables our detailed investigation on the characteristics of somatic mutations in heterogeneous normal cells.

11.
Int J Med Sci ; 17(10): 1428-1438, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32624699

RESUMO

Lung cancer has been the leading cause of cancer morbidity and mortality in recent years. Most lung cancers are often asymptomatic until advanced or metastatic stage. Therefore, looking for the diagnostic biomarker for early-stage lung cancer is quite significant. Circulating exosomal microRNAs (miRNAs) have been reported to be the diagnostic and prognostic markers of various cancers. Here, we obtained circulating exosomal miRNA repertoires of 7 early-stage lung adenocarcinoma patients including pre-operation and post-operation (LA-pre and LA-post) and 7 heathy controls (HCs) by next generation sequence (NGS) and selected miR-342-5p, miR-574-5p and miR-222-3p to validate in ampliative samples by reverse transcription-quantitative PCR (RT-qPCR). Circulating exosomal miR-342-5p, miR-574-5p and miR-222-3p not only significantly elevated in LA patients (n = 56) compared with HCs (n = 40), but also significantly decreased after tumor resection when analyzed 51 paired pre- and post-operation samples. Furthermore, miR-342-5p and miR-574-5p, but not miR-222-3p, had a significantly elevated expression level in carcinoma tissue compared with adjacent non-cancerous tissue (n = 8). The receiver operating characteristic (ROC) curve showed the area under the curve (AUC) of combined miR-342-5p and miR-574-5p was 0.813 (95% CI: 0.7249 to 0.9009) with sensitivity and specificity of 80.0% and 73.2% respectively. In summary, circulating exosomal miR-342-5p and miR-574-5p have potential to serve as novel diagnostic biomarkers for early-stage LA.


Assuntos
Adenocarcinoma de Pulmão/metabolismo , Adenocarcinoma de Pulmão/patologia , Exossomos/metabolismo , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , MicroRNAs/metabolismo , Adenocarcinoma de Pulmão/genética , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Western Blotting , Exossomos/genética , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Regulação Neoplásica da Expressão Gênica/fisiologia , Humanos , Neoplasias Pulmonares/genética , Masculino , MicroRNAs/genética , Pessoa de Meia-Idade
12.
Proc Natl Acad Sci U S A ; 117(8): 4392-4399, 2020 02 25.
Artigo em Inglês | MEDLINE | ID: mdl-32041882

RESUMO

The pathogenesis of bipolar disorder (BD) has remained enigmatic, largely because genetic animal models based on identified susceptible genes have often failed to show core symptoms of spontaneous mood cycling. However, pedigree and induced pluripotent stem cell (iPSC)-based analyses have implicated that dysfunction in some key signaling cascades might be crucial for the disease pathogenesis in a subpopulation of BD patients. We hypothesized that the behavioral abnormalities of patients and the comorbid metabolic abnormalities might share some identical molecular mechanism. Hence, we investigated the expression of insulin/synapse dually functioning genes in neurons derived from the iPSCs of BD patients and the behavioral phenotype of mice with these genes silenced in the hippocampus. By these means, we identified synaptotagmin-7 (Syt7) as a candidate risk factor for behavioral abnormalities. We then investigated Syt7 knockout (KO) mice and observed nocturnal manic-like and diurnal depressive-like behavioral fluctuations in a majority of these animals, analogous to the mood cycling symptoms of BD. We treated the Syt7 KO mice with clinical BD drugs including olanzapine and lithium, and found that the drug treatments could efficiently regulate the behavioral abnormalities of the Syt7 KO mice. To further verify whether Syt7 deficits existed in BD patients, we investigated the plasma samples of 20 BD patients and found that the Syt7 mRNA level was significantly attenuated in the patient plasma compared to the healthy controls. We therefore concluded that Syt7 is likely a key factor for the bipolar-like behavioral abnormalities.


Assuntos
Transtorno Bipolar/metabolismo , Transtorno Bipolar/psicologia , Sinaptotagminas/metabolismo , Adulto , Animais , Comportamento , Transtorno Bipolar/sangue , Transtorno Bipolar/genética , Feminino , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Masculino , Camundongos , Camundongos Knockout , Neurônios/metabolismo , Sinaptotagminas/genética , Adulto Jovem
13.
Zhongguo Zhong Yao Za Zhi ; 44(1): 34-39, 2019 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-30868809

RESUMO

As a large micro-ecosystem in the human body,the intestinal microbiota is closely associated with the occurrence of many diseases.The clinical investigations and animal experiments have showed that traditional Chinese medicine(TCM) could maintain the balance of the intestinal micro-ecological system.This review summarized the research methods and literatures on the regulation effects of TCM,including different effective ingredients,extracts and Chinese herbal formulae,on intestinal microflora in recent five years,in order to provide a reference for the further research and development of TCM.


Assuntos
Microbioma Gastrointestinal/efeitos dos fármacos , Medicina Tradicional Chinesa , Animais , Humanos , Intestinos/microbiologia , Pesquisa/tendências
14.
Nat Neurosci ; 21(6): 894, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29545585

RESUMO

In the version of this article initially published, the affiliation for Jian Zhang and Shuangli Mi was incomplete. In addition to the Key Laboratory of Genomics and Precision Medicine, they are also affiliated with the University of Chinese Academy of Sciences, Beijing, China. In Supplementary Fig. 1h,l, the molecular mass marker accompanying Snap25 was labeled 58 kDa; the correct value is 25 kDa. In Supplementary Fig. 9b,c, the top panel was labeled Syt1, with molecular mass markers ranging from 46 to 100 kDa; it is actually Snap25, with molecular mass markers ranging from 17 to 46 kDa. The errors have been corrected in the HTML and PDF versions of the article.

15.
Nat Neurosci ; 21(3): 447-454, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29403034

RESUMO

CRISPR-Cas9 has been demonstrated to delete genes in postmitotic neurons. Compared to the establishment of proliferative cell lines or animal strains, it is more challenging to acquire a highly homogeneous consequence of gene editing in a stable neural network. Here we show that dCas9-based CRISPR interference (CRISPRi) can efficiently silence genes in neurons. Using a pseudotarget fishing strategy, we demonstrate that CRISPRi shows superior targeting specificity without detectable off-target activity. Furthermore, CRISPRi can achieve multiplex inactivation of genes fundamental for neurotransmitter release with high efficiency. By developing conditional CRISPRi tools targeting synaptotagmin I (Syt1), we modified the excitatory to inhibitory balance in the dentate gyrus of the mouse hippocampus and found that the dentate gyrus has distinct regulatory roles in learning and affective processes in mice. We therefore recommend CRISPRi as a useful tool for more rapid investigation of gene function in the mammalian brain.


Assuntos
Química Encefálica/genética , Sistemas CRISPR-Cas/genética , Afeto/fisiologia , Animais , Proliferação de Células , Cognição/fisiologia , Giro Denteado/metabolismo , Medo/psicologia , Inativação Gênica , Elevação dos Membros Posteriores/psicologia , Aprendizagem/fisiologia , Masculino , Aprendizagem em Labirinto , Memória/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Interferência de RNA , Sinaptotagmina I/genética
18.
Nature ; 527(7576): 95-9, 2015 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-26524527

RESUMO

Bipolar disorder is a complex neuropsychiatric disorder that is characterized by intermittent episodes of mania and depression; without treatment, 15% of patients commit suicide. Hence, it has been ranked by the World Health Organization as a top disorder of morbidity and lost productivity. Previous neuropathological studies have revealed a series of alterations in the brains of patients with bipolar disorder or animal models, such as reduced glial cell number in the prefrontal cortex of patients, upregulated activities of the protein kinase A and C pathways and changes in neurotransmission. However, the roles and causation of these changes in bipolar disorder have been too complex to exactly determine the pathology of the disease. Furthermore, although some patients show remarkable improvement with lithium treatment for yet unknown reasons, others are refractory to lithium treatment. Therefore, developing an accurate and powerful biological model for bipolar disorder has been a challenge. The introduction of induced pluripotent stem-cell (iPSC) technology has provided a new approach. Here we have developed an iPSC model for human bipolar disorder and investigated the cellular phenotypes of hippocampal dentate gyrus-like neurons derived from iPSCs of patients with bipolar disorder. Guided by RNA sequencing expression profiling, we have detected mitochondrial abnormalities in young neurons from patients with bipolar disorder by using mitochondrial assays; in addition, using both patch-clamp recording and somatic Ca(2+) imaging, we have observed hyperactive action-potential firing. This hyperexcitability phenotype of young neurons in bipolar disorder was selectively reversed by lithium treatment only in neurons derived from patients who also responded to lithium treatment. Therefore, hyperexcitability is one early endophenotype of bipolar disorder, and our model of iPSCs in this disease might be useful in developing new therapies and drugs aimed at its clinical treatment.


Assuntos
Potenciais de Ação/efeitos dos fármacos , Antipsicóticos/farmacologia , Transtorno Bipolar/patologia , Compostos de Lítio/farmacologia , Neurônios/efeitos dos fármacos , Neurônios/patologia , Sinalização do Cálcio/efeitos dos fármacos , Giro Denteado/efeitos dos fármacos , Giro Denteado/patologia , Endofenótipos , Humanos , Células-Tronco Pluripotentes Induzidas/patologia , Masculino , Mitocôndrias/patologia , Técnicas de Patch-Clamp
19.
Genomics Proteomics Bioinformatics ; 13(1): 17-24, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25724326

RESUMO

Exosomes are 40-100 nm nano-sized vesicles that are released from many cell types into the extracellular space. Such vesicles are widely distributed in various body fluids. Recently, mRNAs and microRNAs (miRNAs) have been identified in exosomes, which can be taken up by neighboring or distant cells and subsequently modulate recipient cells. This suggests an active sorting mechanism of exosomal miRNAs, since the miRNA profiles of exosomes may differ from those of the parent cells. Exosomal miRNAs play an important role in disease progression, and can stimulate angiogenesis and facilitate metastasis in cancers. In this review, we will introduce the origin and the trafficking of exosomes between cells, display current research on the sorting mechanism of exosomal miRNAs, and briefly describe how exosomes and their miRNAs function in recipient cells. Finally, we will discuss the potential applications of these miRNA-containing vesicles in clinical settings.


Assuntos
Exossomos/genética , MicroRNAs/fisiologia , Neoplasias/genética , RNA Mensageiro/genética , Animais , Humanos
20.
Nat Genet ; 46(3): 287-93, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24509477

RESUMO

Acute leukemia characterized by chromosomal rearrangements requires additional molecular disruptions to develop into full-blown malignancy, yet the cooperative mechanisms remain elusive. Using whole-genome sequencing of a pair of monozygotic twins discordant for MLL (also called KMT2A) gene-rearranged leukemia, we identified a transforming MLL-NRIP3 fusion gene and biallelic mutations in SETD2 (encoding a histone H3K36 methyltransferase). Moreover, loss-of-function point mutations in SETD2 were recurrent (6.2%) in 241 patients with acute leukemia and were associated with multiple major chromosomal aberrations. We observed a global loss of H3K36 trimethylation (H3K36me3) in leukemic blasts with mutations in SETD2. In the presence of a genetic lesion, downregulation of SETD2 contributed to both initiation and progression during leukemia development by promoting the self-renewal potential of leukemia stem cells. Therefore, our study provides compelling evidence for SETD2 as a new tumor suppressor. Disruption of the SETD2-H3K36me3 pathway is a distinct epigenetic mechanism for leukemia development.


Assuntos
Histona-Lisina N-Metiltransferase/genética , Leucemia/genética , Mutação , Proteínas Adaptadoras de Transdução de Sinal/genética , Pré-Escolar , Aberrações Cromossômicas , Doenças em Gêmeos/genética , Epigênese Genética , Feminino , Fusão Gênica , Genes Supressores de Tumor , Humanos , Leucemia Monocítica Aguda/genética , Proteína de Leucina Linfoide-Mieloide/genética , Proteínas Nucleares/genética , Mutação Puntual , Translocação Genética , Gêmeos Monozigóticos
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