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1.
Proc Natl Acad Sci U S A ; 119(42): e2202133119, 2022 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-36215479

RESUMO

Unfolded protein response (UPR) is the mechanism by which cells control endoplasmic reticulum (ER) protein homeostasis. ER proteostasis is essential to adapt to cell proliferation and regeneration in development and tumorigenesis, but mechanisms linking UPR, growth control, and cancer progression remain unclear. Here, we report that the Ire1/Xbp1s pathway has surprisingly oncogenic and tumor-suppressive roles in a context-dependent manner. Activation of Ire1/Xbp1s up-regulates their downstream target Bip, which sequesters Yorkie (Yki), a Hippo pathway transducer, in the cytoplasm to restrict Yki transcriptional output. This regulation provides an endogenous defensive mechanism in organ size control, intestinal homeostasis, and regeneration. Unexpectedly, Xbp1 ablation promotes tumor overgrowth but suppresses invasiveness in a Drosophila cancer model. Mechanistically, hyperactivated Ire1/Xbp1s signaling in turn induces JNK-dependent developmental and oncogenic cell migration and epithelial-mesenchymal transition (EMT) via repression of Yki. In humans, a negative correlation between XBP1 and YAP (Yki ortholog) target gene expression specifically exists in triple-negative breast cancers (TNBCs), and those with high XBP1 or HSPA5 (Bip ortholog) expression have better clinical outcomes. In human TNBC cell lines and xenograft models, ectopic XBP1s or HSPA5 expression alleviates tumor growth but aggravates cell migration and invasion. These findings uncover a conserved crosstalk between the Ire1/Xbp1s and Hippo signaling pathways under physiological settings, as well as a crucial role of Bip-Yki interaction in tumorigenesis that is shared from Drosophila to humans.


Assuntos
Proteínas de Drosophila , Proteínas Serina-Treonina Quinases , Animais , Carcinogênese/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Drosophila/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Retículo Endoplasmático/metabolismo , Endorribonucleases , Via de Sinalização Hippo , Humanos , Proteínas Serina-Treonina Quinases/genética , Resposta a Proteínas não Dobradas , Proteína 1 de Ligação a X-Box/genética , Proteína 1 de Ligação a X-Box/metabolismo
2.
Br J Cancer ; 128(6): 1086-1094, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36593359

RESUMO

BACKGROUND: Dysregulation of alternative splicing (AS) triggers many tumours, understanding the roles of splicing events during tumorigenesis would open new avenues for therapies and prognosis in multiple myeloma (MM). METHODS: Molecular, genetic, bioinformatic and statistic approaches are used to determine the mechanism of the candidate splicing factor (SF) in myeloma cell lines, myeloma xenograft models and MM patient samples. RESULTS: GSEA reveals a significant difference in the expression pattern of the alternative splicing pathway genes, notably enriched in MM patients. Upregulation of the splicing factor SRSF1 is observed in the progression of plasma cell dyscrasias and predicts MM patients' poor prognosis. The c-indices of the Cox model indicated that SRSF1 improved the prognostic stratification of MM patients. Moreover, SRSF1 knockdown exerts a broad anti-myeloma activity in vitro and in vivo. The upregulation of SRSF1 is caused by the transcription factor YY1, which also functions as an oncogene in myeloma cells. Through RNA-Seq, we systematically verify that SRSF1 promotes the tumorigenesis of myeloma cells by switching AS events. CONCLUSION: Our results emphasise the importance of AS for promoting tumorigenesis of MM. The candidate SF might be considered as a valuable therapeutic target and a potential prognostic biomarker for MM.


Assuntos
Processamento Alternativo , Mieloma Múltiplo , Humanos , Fatores de Processamento de Serina-Arginina/genética , Fatores de Processamento de Serina-Arginina/metabolismo , Fatores de Processamento de RNA/genética , Fatores de Processamento de RNA/metabolismo , Transformação Celular Neoplásica , Carcinogênese
3.
Blood ; 137(12): 1603-1614, 2021 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-32967010

RESUMO

The initiation and progression of diffuse large B-cell lymphoma (DLBCL) is governed by genetic and epigenetic aberrations. As the most abundant eukaryotic messenger RNA (mRNA) modification, N6-methyladenosine (m6A) is known to influence various fundamental bioprocesses by regulating the target gene; however, the function of m6A modifications in DLBCL is unclear. PIWI-interacting RNAs (piRNAs) have been indicated to be epigenetic effectors in cancer. Here, we show that high expression of piRNA-30473 supports the aggressive phenotype of DLBCL, and piRNA-30473 depletion decreases proliferation and induces cell cycle arrest in DLBCL cells. In xenograft DLBCL models, piRNA-30473 inhibition reduces tumor growth. Moreover, piRNA-30473 is significantly associated with overall survival in a univariate analysis and is statistically significant after adjusting for the National Comprehensive Cancer Network-International Prognostic Index in the multivariate analysis. Additional studies demonstrate that piRNA-30473 exerts its oncogenic role through a mechanism involving the upregulation of WTAP, an m6A mRNA methylase, and thus enhances the global m6A level. Integrating transcriptome and m6A-sequencing analyses reveals that WTAP increases the expression of its critical target gene, hexokinase 2 (HK2), by enhancing the HK2 m6A level, thereby promoting the progression of DLBCL. Together, the piRNA-30473/WTAP/HK2 axis contributes to tumorigenesis by regulating m6A RNA methylation in DLBCL. Furthermore, by comprehensively analyzing our clinical data and data sets, we discover that the m6A regulatory genes piRNA-30473 and WTAP improve survival prediction in DLBCL patients. Our study highlights the functional importance of the m6A modification in DLBCL and might assist in the development of a prognostic stratification and therapeutic approach for DLBCL.


Assuntos
Carcinogênese/genética , Regulação Neoplásica da Expressão Gênica , Linfoma Difuso de Grandes Células B/genética , RNA Interferente Pequeno/genética , Epigênese Genética , Humanos , Linfoma Difuso de Grandes Células B/diagnóstico , Metiltransferases/genética , Prognóstico , RNA Mensageiro/genética
4.
Br J Cancer ; 124(11): 1843-1853, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33785876

RESUMO

BACKGROUND: Secondary plasma cell leukaemia (sPCL) is an aggressive form of multiple myeloma (MM), but the mechanism underlying MM progresses into PCL remains unknown. METHODS: Gene expression profiling of MM patients and PCL patients was analysed to identify the molecular differences between the two diseases. Cox survival regression and Kaplan-Meier analysis were performed to illustrate the impact of integrin subunit alpha 6 (ITGA6) on prognosis of MM. Invasion assays were performed to assess whether ITGA6 regulated the progression of MM to PCL. RESULTS: Gene expression profiling analyses showed that cell metastasis pathways were enriched in PCL and ITGA6 was differentially expressed between PCL and MM. ITGA6 expression was an independent prognostic factor for event-free survival (EFS) and overall survival (OS) of MM patients. Moreover, the stratification ability of the International Staging System (ISS) of MM was improved when including ITGA6 expression. Functional studies uncovered that increased ITGA6 reduced the myeloma cell invasion. Additionally, low expression of ITGA6 resulted from epigenetic downregulating of its anti-sense non-coding RNA, ITGA6-AS1. CONCLUSION: Our data reveal that ITGA6 gradually decreases during plasma cell dyscrasias progression and low expression of ITGA6 contributes to myeloma metastasis. Moreover, ITGA6 abundance might help develop MM prognostic stratification.


Assuntos
Integrina alfa6/genética , Leucemia Plasmocitária/genética , Mieloma Múltiplo/genética , Biomarcadores Tumorais/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Progressão da Doença , Regulação para Baixo/genética , Regulação para Baixo/fisiologia , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Integrina alfa6/fisiologia , Leucemia Plasmocitária/diagnóstico , Leucemia Plasmocitária/mortalidade , Leucemia Plasmocitária/patologia , Mieloma Múltiplo/diagnóstico , Mieloma Múltiplo/mortalidade , Mieloma Múltiplo/patologia , Prognóstico
5.
Stem Cells ; 37(2): 247-256, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30353595

RESUMO

The characteristics of mesenchymal stromal cells (MSCs) which derived from multiple myeloma (MM) patients are typically impaired in osteogenic differentiation. However, the underlying molecular mechanisms need to be further investigated. lncRNAs are emerging as critical regulation molecules in oncogenic pathways. In this study, we identified that bioactive lncRNA HOXC-AS3, which is transcribed in opposite to HOXC10, was presented in MSCs derived from bone marrow (BM) of MM patients (MM-MSCs). HOXC-AS3 was able to interact with HOXC10 at the overlapping parts and this interaction increased HOXC10 stability, then promoted its expression, conferring osteogenesis repression to MM-MSCs. In mouse models, intravenously administered siHOXC-AS3 was proven to be effective in prevention of bone loss, sustained by both anticatabolic activities and bone-forming. These data showed that lncHOXC-AS3 was required for osteogenesis in BM-MSCs by enhancing HOXC10 expression. Our finding thus unveils a novel insight for the potential clinical significance of lncRNA HOXC-AS3 as a therapeutic target for bone disease in MM. Stem Cells 2019;37:247-256.


Assuntos
Proteínas de Homeodomínio/metabolismo , Células-Tronco Mesenquimais/metabolismo , Mieloma Múltiplo/metabolismo , Oligonucleotídeos Antissenso/metabolismo , Osteoblastos/metabolismo , RNA Longo não Codificante/metabolismo , Animais , Estudos de Casos e Controles , Diferenciação Celular/fisiologia , Linhagem Celular Tumoral , Células Cultivadas , Feminino , Xenoenxertos , Proteínas de Homeodomínio/genética , Humanos , Células-Tronco Mesenquimais/citologia , Camundongos , Mieloma Múltiplo/genética , Mieloma Múltiplo/patologia , Oligonucleotídeos Antissenso/genética , Osteogênese , RNA Longo não Codificante/genética , Transfecção , Regulação para Cima
6.
Acta Pharmacol Sin ; 41(1): 119-128, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31534201

RESUMO

Inefficient diabetic ulcer healing and scar formation remain a challenge worldwide, owing to a series of disordered and dynamic biological events that occur during the process of healing. A functional wound dressing that is capable of promoting ordered diabetic wound recovery is eagerly anticipated. In this study, we designed a silicone elastomer with embedded 20(S)-protopanaxadiol-loaded nanostructured lipid carriers (PPD-NS) to achieve ordered recovery in scarless diabetic ulcer healing. The nanostructured lipid carriers were prepared through an emulsion evaporation-solidification method and then incorporated into a network of silicone elastomer to form a unique nanostructured lipid carrier-enriched gel formulation. Interestingly, the PPD-NS showed excellent in vitro anti-inflammatory and proangiogenic activity. Moreover, in diabetic mice with full-thickness skin excision wound, treatment with PPD-NS significantly promoted in vivo scarless wound healing through suppressing inflammatory infiltration in the inflammatory phase, promoting angiogenesis during the proliferation phase, and regulating collagen deposition in the remodeling phase. Hence, this study demonstrates that the developed PPD-NS could facilitate ordered diabetic wound recovery via multifunctional improvement during different wound-healing phases. This novel approach could be promising for scarless diabetic wound healing.


Assuntos
Inibidores da Angiogênese/farmacologia , Anti-Inflamatórios não Esteroides/farmacologia , Pé Diabético/tratamento farmacológico , Neovascularização Patológica/tratamento farmacológico , Sapogeninas/farmacologia , Elastômeros de Silicone/química , Inibidores da Angiogênese/administração & dosagem , Animais , Anti-Inflamatórios não Esteroides/administração & dosagem , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Pé Diabético/patologia , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Géis/administração & dosagem , Géis/química , Humanos , Inflamação/tratamento farmacológico , Inflamação/patologia , Lipídeos/química , Lipopolissacarídeos/antagonistas & inibidores , Lipopolissacarídeos/farmacologia , Masculino , Camundongos , Nanoestruturas/química , Neovascularização Patológica/patologia , Óxido Nítrico/antagonistas & inibidores , Óxido Nítrico/biossíntese , Tamanho da Partícula , Células RAW 264.7 , Sapogeninas/administração & dosagem , Sapogeninas/química , Elastômeros de Silicone/administração & dosagem , Propriedades de Superfície , Cicatrização/efeitos dos fármacos
7.
Mediators Inflamm ; 2020: 2960517, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33013197

RESUMO

Insulin resistance has been shown to be the common pathogenesis of many metabolic diseases. Metainflammation is one of the important characteristics of insulin resistance. Macrophage polarization mediates the production and development of metainflammation. Toll-like receptor 4 (TLR4) mediates macrophage activity and is probably the intersection of immunity and metabolism, but the detailed mechanism is probably not fully understood. Activated protein 1 (AP1) signaling pathway is very important in macrophage activation-mediated inflammation. However, it is unclear whether AP1 signaling pathway mediates metabolic inflammation in the liver. We aimed to investigate the effects of macrophage TLR4-AP1 signaling pathway on hepatocyte metabolic inflammation, insulin sensitivity, and lipid deposition, as well as to explore the potential of TLR4-AP1 as new intervention targets of insulin resistance and liver steatosis. TLR4 and AP1 were silenced in the RAW264.7 cells by lentiviral siRNA transfection. In vivo transduction of lentivirus was administered in mice fed with high-fat diet. Insulin sensitivity and inflammation were evaluated in the treated cells or animals. Our results indicated that TLR4/AP-1 siRNA transfection alleviated high-fat diet-induced systemic and hepatic inflammation, obesity, and insulin resistance in mice. Additionally, TLR4/AP-1 siRNA transfection mitigated palmitic acid- (PA-) induced inflammation in RAW264.7 cells and metabolic abnormalities in cocultured AML hepatocytes. Herein, we propose that TLR4-AP1 signaling pathway activation plays a crucial role in high fat- or PA-induced metabolic inflammation and insulin resistance in hepatocytes. Intervention of the TLR4 expression regulates macrophage polarization and metabolic inflammation and further alleviates insulin resistance and lipid deposition in hepatocytes.


Assuntos
Fígado Gorduroso/sangue , Insulina/sangue , Receptor 4 Toll-Like/sangue , Fator de Necrose Tumoral alfa/sangue , Animais , Western Blotting , Colesterol/sangue , Ensaio de Imunoadsorção Enzimática , Ácidos Graxos não Esterificados/sangue , Teste de Tolerância a Glucose , Inflamação/sangue , Interleucina-10/sangue , Interleucina-1beta/sangue , Interleucina-6/sangue , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Células RAW 264.7 , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Triglicerídeos/sangue
8.
Bioinformatics ; 34(21): 3609-3615, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-29850860

RESUMO

Motivation: Molecular analyses suggest that myeloma is composed of distinct sub-types that have different molecular pathologies and various response rates to certain treatments. Drug responses in multiple myeloma (MM) are usually recorded as a multi-level ordinal outcome. One of the goals of drug response studies is to predict which response category any patients belong to with high probability based on their clinical and molecular features. However, as most of genes have small effects, gene-based models may provide limited predictive accuracy. In that case, methods for predicting multi-level ordinal drug responses by incorporating biological pathways are desired but have not been developed yet. Results: We propose a pathway-structured method for predicting multi-level ordinal responses using a two-stage approach. We first develop hierarchical ordinal logistic models and an efficient quasi-Newton algorithm for jointly analyzing numerous correlated variables. Our two-stage approach first obtains the linear predictor (called the pathway score) for each pathway by fitting all predictors within each pathway using the hierarchical ordinal logistic approach, and then combines the pathway scores as new predictors to build a predictive model. We applied the proposed method to two publicly available datasets for predicting multi-level ordinal drug responses in MM using large-scale gene expression data and pathway information. Our results show that our approach not only significantly improved the predictive performance compared with the corresponding gene-based model but also allowed us to identify biologically relevant pathways. Availability and implementation: The proposed approach has been implemented in our R package BhGLM, which is freely available from the public GitHub repository https://github.com/abbyyan3/BhGLM.


Assuntos
Fenômenos Biológicos , Mieloma Múltiplo , Algoritmos , Teorema de Bayes , Humanos , Modelos Logísticos , Mieloma Múltiplo/tratamento farmacológico
9.
BMC Cancer ; 18(1): 551, 2018 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-29747599

RESUMO

BACKGROUND: Multiple myeloma (MM), like other cancers, is caused by the accumulation of genetic abnormalities. Heterogeneity exists in the patients' response to treatments, for example, bortezomib. This urges efforts to identify biomarkers from numerous molecular features and build predictive models for identifying patients that can benefit from a certain treatment scheme. However, previous studies treated the multi-level ordinal drug response as a binary response where only responsive and non-responsive groups are considered. METHODS: It is desirable to directly analyze the multi-level drug response, rather than combining the response to two groups. In this study, we present a novel method to identify significantly associated biomarkers and then develop ordinal genomic classifier using the hierarchical ordinal logistic model. The proposed hierarchical ordinal logistic model employs the heavy-tailed Cauchy prior on the coefficients and is fitted by an efficient quasi-Newton algorithm. RESULTS: We apply our hierarchical ordinal regression approach to analyze two publicly available datasets for MM with five-level drug response and numerous gene expression measures. Our results show that our method is able to identify genes associated with the multi-level drug response and to generate powerful predictive models for predicting the multi-level response. CONCLUSIONS: The proposed method allows us to jointly fit numerous correlated predictors and thus build efficient models for predicting the multi-level drug response. The predictive model for the multi-level drug response can be more informative than the previous approaches. Thus, the proposed approach provides a powerful tool for predicting multi-level drug response and has important impact on cancer studies.


Assuntos
Antineoplásicos/uso terapêutico , Biomarcadores Tumorais/genética , Perfilação da Expressão Gênica , Modelos Biológicos , Mieloma Múltiplo/tratamento farmacológico , Algoritmos , Bortezomib/uso terapêutico , Ensaios Clínicos como Assunto , Conjuntos de Dados como Assunto , Humanos , Modelos Logísticos , Mieloma Múltiplo/genética , Transcriptoma/genética , Resultado do Tratamento
10.
Mol Pharm ; 15(9): 4139-4147, 2018 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-30048594

RESUMO

Several studies demonstrate that the bromodomain inhibitor OTX015 has an antitumor activity in cancers. However, translation of these data to molecules suitable for clinical development has yet to be accomplished in multiple myeloma (MM). Here, we identified genes and biologic processes that substantiated the antimyeloma activity of OTX015 with global transcriptomics. OTX015 exerted a strong antiproliferative effect and induced cell cycle arrest in vitro. Gene expression profiling uncovered that OTX015 targeted NF-κB, EGFR, cell cycle regulation, and the cancer proliferation signaling pathway. Gene expression signatures displaying various levels of sensitivity to OTX015 were also identified. The data also showed that oral administration of OTX015 displayed significant antitumor activity in the mice model of disseminated human myeloma. In addition, our study provided the first evidence and rationale that OTX015 could promote osteoblast differentiation of mesenchymal stem cells (MSCs) and inhibited osteoclast formation and resorption in vivo experiments. Herein our results expanded the understanding of the mechanism for BET inhibitors OTX015 in MM. Our study provided an impressive basis for the clinical application of the novel antimyeloma agent OTX015 and uncovered signaling pathways that may play key roles in myeloma cell proliferation.


Assuntos
Acetanilidas/uso terapêutico , Antineoplásicos/uso terapêutico , Compostos Heterocíclicos com 3 Anéis/uso terapêutico , Mieloma Múltiplo/tratamento farmacológico , Proteínas/antagonistas & inibidores , Animais , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Camundongos , Mieloma Múltiplo/metabolismo , Osteogênese/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Mol Pharm ; 15(11): 5387-5396, 2018 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-30339013

RESUMO

Treatment failure remains a main challenge in the management of high-risk multiple myeloma (MM) even with the expanding repertoire of new drugs. Combinatorial therapy is considered an encouraging strategy that can overcome the compensatory mechanisms and undesirable off-target effects that limit the benefits of many prospective agents. Preliminary results of a current phase I trial have indicated that the new BET bromodomain inhibitor OTX015 has favorable activity and tolerability. However, OTX015 is not efficacious enough as a monotherapy. Here, we provide evidence that synergistic drug combinations with OTX015 were generally more specific to particular cellular contexts than single agent activities. In addition, pairing OTX015 with three classes of drugs dramatically enhanced the antitumor activity in mouse models of disseminated human myeloma. Our studies further underscored that the BET inhibitor OTX015 sensitized MM cells by interrupting several pathways and genes critical for MM cell proliferation and drug response, which provided the rationale for multiple myeloma therapy with OTX015 combined with conventional chemotherapeutic drugs. Thus, the context specificity of synergistic combinations not only provide profound insights into therapeutically relevant selectivity but also improve control of complex biological systems.


Assuntos
Acetanilidas/farmacocinética , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Compostos Heterocíclicos com 3 Anéis/farmacocinética , Mieloma Múltiplo/tratamento farmacológico , Acetanilidas/uso terapêutico , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Linhagem Celular Tumoral , Sinergismo Farmacológico , Compostos Heterocíclicos com 3 Anéis/uso terapêutico , Humanos , Camundongos , Mieloma Múltiplo/patologia , Estudos Prospectivos , Proteínas/antagonistas & inibidores , Ensaios Antitumorais Modelo de Xenoenxerto
12.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(10): 3410-3, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30247001

RESUMO

In order to enhance the monitoring of paddy growth, utilize the fertilizer more efficiently, increase crop yield and improve the quality of grain, thus the system of laser-induced fluorescence (LIF) was built. The system was designed to study the relationship between the rice leaf chlorophyll content and fluorescence ratio. In this paper, the samples came from the second upper leaves of paddy in shooting stage and the cultivated area was located in Jianghan plain of China. Firstly, the Kjeldahl method combined with the formula which was described by Zivcak et al. was utilized to calculate the chlorophyll content of paddy, then the fluorescence spectrum of paddy leaf with different chlorophyll content by the instrument of laser-induced fluorescence (the wavelength of excitation 355 nm). Fluorescence spectra of paddy leaf with different chlorophyll content were collected and then a fluorescence spectra database was established. It is discussed that the relationship between the ratio of fluorescence (F740/F685 is the ratio of fluorescence intensity of 740 nm dividing that by 685 nm) and the chlorophyll content of paddy. It is found that the effect of chlorophyll content on the fluorescence spectral characteristics is evident. The results demonstrated that it has the tightly positive correlation between the fluorescence ratio (F740/F685) and chlorophyll content of paddy leaf. The determination coefficient (R2) can reach up to 0.901 3 and 0.912 5 at tillering stage and shooting stage, respectively. The experimental analysis showed that the LIF technology has the advantages of convenient, quick and nondestructive, and it has the potential for quantitative monitoring of crop growth.

13.
Small ; 11(14): 1683-90, 2015 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-25408470

RESUMO

Ultrasmall gold nanoclusters (Au NCs) show great potential in biomedical applications. Long-term biodistribution, retention, toxicity, and pharmacokinetics profiles are pre-requisites in their potential clinical applications. Here, the biodistribution, clearance, and toxicity of one widely used Au NC species-glutathione-protected Au NCs or GSH-Au NCs-are systematically investigated over a relatively long period of 90 days in mice. Most of the Au NCs are cleared at 30 days post injection (p.i.) with a major accumulation in liver and kidney. However, it is surprising that an abnormal increase of the Au amount in the heart, liver, spleen, lung, and testis is observed at 60 and 90 days p.i., indicating that the injected Au NCs form a V-shaped time-dependent distribution profile in various organs. Further investigations reveal that Au NCs are steadily accumulating in the muscle in the first 30 days p.i., and the as-stored Au NCs gradually release into the blood in 30-90 days p.i., which induces a re-distribution and re-accumulation of Au NCs in all blood-rich organs. Further hematology and biochemistry studies show that the re-accumulation of Au NCs still causes some liver toxicity at 30 days p.i. The muscle storage and subsequent release may give rise to the potential accumulation and toxicity risk of functional nanomaterials over long periods of time.


Assuntos
Ouro/química , Músculos/química , Nanoestruturas , Animais , Camundongos , Microscopia Eletrônica de Transmissão , Distribuição Tecidual
14.
Zhongguo Zhong Yao Za Zhi ; 40(15): 3027-33, 2015 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-26677706

RESUMO

To discuss the effect of puerarin (Pue) on the proliferation of hypoxia-induced pulmonary artery smooth muscle cells (PASMCs) and discuss whether its mechanism is achieved by regulating reactive oxygen. PASMCs of primarily cultured rats (2-5 generations) were selected in the experiment. MTT, Western blot, FCM and DCFH-DA were used to observe Pue's effect the proliferation of PASMCs. The Western blot was adopted to detect whether ROS participated in Pue's effect in inhibiting PASMC proliferation. The PASMCs were divided into five groups: the normoxia group, the hypoxia group, the hypoxia + Pue group, the hypoxia + Pue + Rotenone group and the hypoxia + Rotenone group, with Rotenone as the ROS blocker. According to the results, under the conditions of normoxia, Pue had no effect on the PASMC proliferation; But, under the conditions of hypoxia, it could inhibit the PASMC proliferation; Under the conditions of normoxia and hypoxia, Pue had no effect on the expression of the tumor necrosis factor-α (TNF-α) among PASMCs, could down-regulate the expression of hypoxia-induced cell cycle protein Cyclin A and proliferative nuclear antigen (PCNA). DCFH-DA proved Pue could reverse ROS rise caused by hypoxia. Both Rotenone and Pue could inhibit the up-regulated expressions of HIF-1α, Cyclin A, PCNA caused by anoxia, with a synergistic effect. The results suggested that Pue could inhibit the hypoxia-induced PASMC proliferation. Its mechanism may be achieved by regulating ROS.


Assuntos
Proliferação de Células/efeitos dos fármacos , Isoflavonas/farmacologia , Miócitos de Músculo Liso/efeitos dos fármacos , Artéria Pulmonar/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Animais , Ciclo Celular/efeitos dos fármacos , Células Cultivadas , Hipóxia/patologia , Masculino , Miócitos de Músculo Liso/fisiologia , Antígeno Nuclear de Célula em Proliferação/análise , Artéria Pulmonar/citologia , Ratos , Ratos Wistar
15.
Zhongguo Zhong Yao Za Zhi ; 40(15): 3041-6, 2015 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-26677708

RESUMO

To discuss the effect of puerarin (Pue) on the proliferation of hypoxia-induced pulmonary artery smooth muscle cells (PASMCs) and discuss whether the extracellular signal PI3K/AKT pathway was involved in the Pue-induced PASMC apoptosis. With the serum starvation group (SD group) as the control group, the MTT colorimetry method, Annexin V-FITC apoptosis detection kit and Western blot were used to detect Pue's effect on apoptosis of rat PASMCs. The protein immunoblot assay was used to detect whether PI3K/AKT pathway was involved in the inhibition of hypoxia-induced PASMC apoptosis process. The results show that under normoxic conditions, Pue had no effect on PASMC apoptosis; Under hypoxia conditions, Pue can inhibit PASMC apoptosis; Under normoxic and hypoxic conditions, Pue had no effect on TNF-α expression. Pue can reverse hypoxia-induced Bcl-2 (P <0.01), up-regulate it and down-regulated Bax (P <0.01). Under normoxic conditions, Pue had no effect on P-AKT expression. Both LY294002 and Pue can inhibit hypoxia-induced Bcl-2, up-regulation of P-AKT expression and down-regulation of Bax expression. Compared with the hypoxia + Pue group or the hypoxia + LY294002 group, the hypoxia + Pue + LY294002 group showed more significantly changes in Bcl-2, Bax, P-AKT expressions. The results show that, Pue can inhibit the hypoxic-induced PASMC apoptosis, which may be regulated through PI3K/AKT pathway.


Assuntos
Apoptose/efeitos dos fármacos , Isoflavonas/farmacologia , Miócitos de Músculo Liso/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/fisiologia , Proteínas Proto-Oncogênicas c-akt/fisiologia , Artéria Pulmonar/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Animais , Células Cultivadas , Cromonas/farmacologia , Morfolinas/farmacologia , Artéria Pulmonar/citologia , Ratos , Ratos Wistar
16.
Immunol Invest ; 43(4): 360-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24484319

RESUMO

Dendritic cells (DCs) are the most powerful antigen-presenting cells that have an important role in the immunity and immune tolerance. Transforming growth factor ß (TGF-ß) is a pleiotropic cytokine widely expressing in various tissues and cells, which regulates cellular proliferation, differentiation and apoptosis of several immune cells and is considered to be a key factor in inducing immune tolerance. The effect of TGF-ß on DCs is very complex. In this study, we further investigated the effect of TGF-ß on inducing immune tolerance of DCs. DCs were differentiated from mice bone marrow cells in the absence or presence of TGF-ß. The phenotype as well as function was studied in detail. We found that TGF-ß limited the expression of CD40, CD83, CD86 and MHCII in DCs, increased CD45RB and indoleamine 2, 3-dioxygenase (IDO) expression in DCs, promoted IL-10 and limited IL-12 secretion by DCs. Moreover, TGF-ß increased the endocytosis ability of DCs and limited the ability of DCs in activating T cells. These results suggest that TGF-ß affects the immunity of DCs and enhances their tolerogenicity.


Assuntos
Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Tolerância Imunológica/genética , Fator de Crescimento Transformador beta/metabolismo , Animais , Antígenos de Superfície/genética , Antígenos de Superfície/metabolismo , Células Dendríticas/efeitos dos fármacos , Endocitose/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Imunofenotipagem , Interleucina-10/biossíntese , Interleucina-12/biossíntese , Ativação Linfocitária/efeitos dos fármacos , Masculino , Camundongos , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Fator de Crescimento Transformador beta/farmacologia
17.
R Soc Open Sci ; 11(7): 231960, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39050727

RESUMO

Many behavioural interactions in real life involve three individuals. When each individual has two alternative strategies, they can be abstracted into mathematical models by means of 2 × 2 × 2 asymmetric games. In this paper, we explore a special class of 2 × 2 × 2 asymmetric games satisfying fixed conditions. Firstly, we analyse two solitary interior equilibrium points and provide the judgement condition for their instability based on the Jacobi matrix local stability analysis method. Secondly, we analyse the interior equilibrium points that are continuously distributed within a line and probe into their stability conditions based on generalized Hamiltonian systems theory. Under the circumstances, the stable interior equilibrium point is surrounded by closed orbits in phase space, which presents an observable stable state where two strategies coexist and fluctuate in each of the three game populations. This work enriches the study of 2 × 2 × 2 asymmetric games' evolutionary dynamics.

18.
Pediatr Obes ; 19(8): e13145, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38890760

RESUMO

BACKGROUND AND OBJECTIVES: This study aimed to examine the associations between breastfeeding duration and metabolic syndrome (MetS) in adolescents and to further investigate the role of birth weight for gestational age (GA) on these associations. METHODS: A total of 10 275 participants aged 7 to 18 years were included applying multistage cluster random sampling from a Chinese national survey. Birth weight was classified into small for GA (SGA), appropriate for GA (AGA) and large for GA (LGA). Information was collected through a self-administered questionnaire, physical examination and blood biochemical examination. Multivariable linear regression, logistic regression models, restricted cubic spline models were applied to assess the relationships of breastfeeding duration and MetS with different birth weight for GA. RESULTS: The prevalence of non-breastfeeding, 0-5, 6-12 and >12 months groups were 16.2%, 23.1%, 42.5% and 18.2%, and the prevalence of SGA and LGA was 11.9% and 12.7%, respectively. Prolonged breastfeeding duration was associated with higher odds of MetS (ß: 0.08, 95% CI: 0.03, 0.13), WC (ß: 3.49, 95% CI: 2.82, 4.16) and SBP (ß: 2.34, 95% CI: 1.80, 2.89). SGA and prolonged breastfeeding synergistically increased MetS risks, but LGA appeared to offset the adverse effects of prolonged breastfeeding. CONCLUSION: Prolonged breastfeeding may increase children's MetS risks. SGA synergies with prolonged breastfeeding increased MetS burden in children and adolescents, while LGA mitigated the risks. This reminds us that intensive attention should be paid to both early birth weight and subsequent living environment for children and adolescents' lifelong health.


Assuntos
Peso ao Nascer , Aleitamento Materno , Idade Gestacional , Síndrome Metabólica , Humanos , Aleitamento Materno/estatística & dados numéricos , Síndrome Metabólica/epidemiologia , Feminino , Adolescente , Masculino , Criança , China/epidemiologia , Prevalência , Fatores de Tempo , Recém-Nascido , Fatores de Risco , Recém-Nascido Pequeno para a Idade Gestacional , Estudos Transversais
19.
Inorg Chem ; 52(15): 8694-8, 2013 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-23879682

RESUMO

Colloidal layered double hydroxides (LDH) nanosheets were sorted by their lateral sizes using a density gradient ultracentrifuge separation technique. Composition investigations on these size-sorted nanosheets indicated that larger sheets had higher Mg:Al ratio than the smaller ones. Experiments using different Mg:Al feed ratios confirmed that high Mg:Al ratio induced fast sheet growth speed. Tracking the source of the Mg:Al spatial distribution difference in one batch of synthesis at the nucleation process revealed the coprecipitation-redissolution of Mg(2+). Thus the discriminative separation of these nanosheets led to a new insight into the structure-composition relationship of LDH nanomaterials and more understanding on their formation mechanism.

20.
Cell Death Dis ; 14(9): 602, 2023 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-37699871

RESUMO

The Hippo pathway is a master regulator of organ growth, stem cell renewal, and tumorigenesis, its activation is tightly controlled by various post-translational modifications, including ubiquitination. While several E3 ubiquitin ligases have been identified as regulators of Hippo pathway, the corresponding E2 ubiquitin-conjugating enzymes (E2s) remain unknown. Here, we performed a screen in Drosophila to identify E2s involved in regulating wing overgrowth caused by the overexpression of Crumbs (Crb) intracellular domain and identified Bruce as a critical regulator. Loss of Bruce downregulates Hippo target gene expression and suppresses Hippo signaling inactivation induced tissue growth. Unexpectedly, our genetic data indicate that Bruce acts upstream of Expanded (Ex) but in parallel with the canonical Hippo (Hpo) -Warts (Wts) cascade to regulate Yorkie (Yki), the downstream effector of Hippo pathway. Mechanistically, Bruce synergizes with E3 ligase POSH to regulate growth and ubiquitination-mediated Ex degradation. Moreover, we demonstrate that Bruce is required for Hippo-mediated malignant tumor progression. Altogether, our findings unveil Bruce as a crucial E2 enzyme that bridges the signal from the cell surface to regulate Hippo pathway activation in Drosophila.


Assuntos
Via de Sinalização Hippo , Ubiquitina-Proteína Ligases , Animais , Carcinogênese , Membrana Celular , Drosophila , Ubiquitina-Proteína Ligases/genética
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