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An amendment to this paper has been published and can be accessed via a link at the top of the paper.
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Systemic immunosuppression greatly affects the chemotherapeutic antitumor effect. Here, we showed that CD19+ extracellular vesicles (EVs) from B cells through CD39 and CD73 vesicle-incorporated proteins hydrolyzed ATP from chemotherapy-treated tumor cells into adenosine, thus impairing CD8+ T cell responses. Serum CD19+ EVs were increased in tumor-bearing mice and patients. Patients with fewer serum CD19+ EVs had a better prognosis after chemotherapy. Upregulated hypoxia-inducible factor-1α (HIF-1α) promoted B cells to release CD19+ EVs by inducing Rab27a mRNA transcription. Rab27a or HIF-1α deficiency in B cells inhibited CD19+ EV production and improved the chemotherapeutic antitumor effect. Silencing of Rab27a in B cells by inactivated Epstein-Barr viruses carrying Rab27a siRNA greatly improved chemotherapeutic efficacy in humanized immunocompromised NOD PrkdcscidIl2rg-/- mice. Thus, decreasing CD19+ EVs holds high potential to improve the chemotherapeutic antitumor effect.
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Linfócitos B/imunologia , Linfócitos T CD8-Positivos/imunologia , Vesículas Extracelulares/imunologia , Animais , Antígenos CD19/imunologia , Linhagem Celular , Linhagem Celular Tumoral , Feminino , Células HEK293 , Herpesvirus Humano 4/imunologia , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Células NIH 3T3 , RNA Mensageiro/imunologia , Transcrição Gênica/imunologia , Proteínas rab27 de Ligação ao GTP/imunologiaRESUMO
RIG-I is a critical RNA virus sensor that serves to initiate antiviral innate immunity. However, posttranslational regulation of RIG-I signaling remains to be fully understood. We report here that RNA viruses, but not DNA viruses or bacteria, specifically upregulate lectin family member Siglecg expression in macrophages by RIG-I- or NF-κB-dependent mechanisms. Siglec-G-induced recruitment of SHP2 and the E3 ubiquitin ligase c-Cbl to RIG-I leads to RIG-I degradation via K48-linked ubiquitination at Lys813 by c-Cbl. By increasing type I interferon production, targeted inactivation of Siglecg protects mice against lethal RNA virus infection. Taken together, our data reveal a negative feedback loop of RIG-I signaling and identify a Siglec-G-mediated immune evasion pathway exploited by RNA viruses with implication in antiviral applications. These findings also provide insights into the functions and crosstalk of Siglec-G, a known adaptive response regulator, in innate immunity.
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RNA Helicases DEAD-box/metabolismo , Infecções por Bactérias Gram-Negativas/imunologia , Imunidade Inata , Lectinas/metabolismo , Infecções por Vírus de RNA/imunologia , Receptores de Antígenos de Linfócitos B/metabolismo , Animais , Proteína DEAD-box 58 , RNA Helicases DEAD-box/química , Células Dendríticas/imunologia , Bactérias Gram-Negativas/metabolismo , Fator Regulador 3 de Interferon/metabolismo , Lectinas/genética , Lisina/metabolismo , Macrófagos/imunologia , Camundongos , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 11/metabolismo , Proteínas Proto-Oncogênicas c-cbl/metabolismo , Vírus de RNA/metabolismo , Receptores de Antígenos de Linfócitos B/genética , Lectinas Semelhantes a Imunoglobulina de Ligação ao Ácido Siálico , UbiquitinaçãoRESUMO
The key molecular mechanisms that control signaling via T cell antigen receptors (TCRs) remain to be fully elucidated. Here we found that Nrdp1, a ring finger-type E3 ligase, mediated Lys33 (K33)-linked polyubiquitination of the signaling kinase Zap70 and promoted the dephosphorylation of Zap70 by the acidic phosphatase-like proteins Sts1 and Sts2 and thereby terminated early TCR signaling in CD8(+) T cells. Nrdp1 deficiency significantly promoted the activation of naive CD8(+) T cells but not that of naive CD4(+) T cells after engagement of the TCR. Nrdp1 interacted with Zap70 and with Sts1 and Sts2 and connected K33 linkage of Zap70 to Sts1- and Sts2-mediated dephosphorylation. Our study suggests that Nrdp1 terminates early TCR signaling by inactivating Zap70 and provides new mechanistic insights into the non-proteolytic regulation of TCR signaling by E3 ligases.
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Linfócitos T CD8-Positivos/imunologia , Proteínas de Transporte/imunologia , Ativação Linfocitária/imunologia , Lisina/imunologia , Proteína-Tirosina Quinase ZAP-70/imunologia , Animais , Linfócitos T CD8-Positivos/metabolismo , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Ativação Linfocitária/genética , Lisina/genética , Lisina/metabolismo , Camundongos Congênicos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microscopia Confocal , Fosforilação/imunologia , Poliubiquitina/imunologia , Poliubiquitina/metabolismo , Ligação Proteica/imunologia , Interferência de RNA , Receptores de Antígenos de Linfócitos T/genética , Receptores de Antígenos de Linfócitos T/imunologia , Receptores de Antígenos de Linfócitos T/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/genética , Transdução de Sinais/imunologia , Transcriptoma/genética , Transcriptoma/imunologia , Ubiquitina-Proteína Ligases , Ubiquitinação/imunologia , Proteína-Tirosina Quinase ZAP-70/metabolismoRESUMO
Excessive activation of dendritic cells (DCs) leads to the development of autoimmune and inflammatory diseases, which has prompted a search for regulators of DC activation. Here we report that Rhbdd3, a member of the rhomboid family of proteases, suppressed the activation of DCs and production of interleukin 6 (IL-6) triggered by Toll-like receptors (TLRs). Rhbdd3-deficient mice spontaneously developed autoimmune diseases characterized by an increased abundance of the TH17 subset of helper T cells and decreased number of regulatory T cells due to the increase in IL-6 from DCs. Rhbdd3 directly bound to Lys27 (K27)-linked polyubiquitin chains on Lys302 of the modulator NEMO (IKKγ) via the ubiquitin-binding-association (UBA) domain in endosomes. Rhbdd3 further recruited the deubiquitinase A20 via K27-linked polyubiquitin chains on Lys268 to inhibit K63-linked polyubiquitination of NEMO and thus suppressed activation of the transcription factor NF-κB in DCs. Our data identify Rhbdd3 as a critical regulator of DC activation and indicate K27-linked polyubiquitination is a potent ubiquitin-linked pattern involved in the control of autoimmunity.
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Proteínas Reguladoras de Apoptose/fisiologia , Autoimunidade , Células Dendríticas/imunologia , Interleucina-6/biossíntese , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Ubiquitinação , Animais , Interleucina-6/antagonistas & inibidores , Lisina/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , NF-kappa B/fisiologia , Estrutura Terciária de Proteína , Linfócitos T/imunologia , Receptores Toll-Like/fisiologiaRESUMO
Leymus chinensis, a dominant perennial grass in the Eurasian Steppe, is well known for its remarkable adaptability and forage quality. Hardly any breeding has been done on the grass, limiting its potential in ecological restoration and forage productivity. To enable genetic improvement of the untapped, important species, we obtained a 7.85-Gb high-quality genome of L. chinensis with a particularly long contig N50 (318.49 Mb). Its allotetraploid genome is estimated to originate 5.29 million years ago (MYA) from a cross between the Ns-subgenome relating to Psathyrostachys and the unknown Xm-subgenome. Multiple bursts of transposons during 0.433-1.842 MYA after genome allopolyploidization, which involved predominantly the Tekay and Angela of LTR retrotransposons, contributed to its genome expansion and complexity. With the genome resource available, we successfully developed a genetic transformation system as well as the gene-editing pipeline in L. chinensis. We knocked out the monocot-specific miR528 using CRISPR/Cas9, resulting in the improvement of yield-related traits with increases in the tiller number and growth rate. Our research provides valuable genomic resources for Triticeae evolutionary studies and presents a conceptual framework illustrating the utilization of genomic information and genome editing to accelerate the improvement of wild L. chinensis with features such as polyploidization and self-incompatibility.
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Melhoramento Vegetal , Poaceae , Poaceae/genética , Genoma , Evolução MolecularRESUMO
The jasmonic acid (JA) signaling pathway is involved in the plant response to drought stress. JA and other hormones synergistically regulate the drought response in plants. However, the molecular mechanism underlying this synergism remains poorly defined. In the present study, transcriptome analyses of guard cells and quantitative PCR experiments revealed that MYC2 negatively regulated the negative regulator of ABA signaling, SlPP2C1, and the type-B response regulator in the cytokinin pathway, SlRR26, and this negative regulation was direct. SlRR26 overexpression reduced drought tolerance in transgenic tomatoes, whereas slrr26cr lines were more tolerant to drought. SlRR26 negatively modulated reactive oxygen species levels in stomata and stomatal closure through RobhB. Moreover, SlRR26 overexpression counteracted JA-mediated stomatal closure, suggesting that SlRR26 played a negative role in the JA-mediated drought response. These findings suggest that MYC2 plays a key role in JA-regulated stomatal closure under drought stress by inhibiting SlPP2C1 and SlRR26.
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Solanum lycopersicum , Fatores de Transcrição , Fatores de Transcrição/metabolismo , Ácido Abscísico/metabolismo , Solanum lycopersicum/genética , Osmorregulação , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Estresse Fisiológico , Estômatos de Plantas/fisiologia , Regulação da Expressão Gênica de Plantas , Plantas/metabolismo , Fosfoproteínas Fosfatases/metabolismo , SecasRESUMO
Chimeric antigen receptor T-cell (CAR-T) therapy targeting B-cell maturation antigen (BCMA) has shown profound efficacy and manageable toxicity in patients with relapsed/refractory multiple myeloma (RRMM). However, determining the best course of treatment for post-CAR-T therapy relapse remains a significant challenge. We conducted a retrospective analysis of patients from the phase I LEGEND-2 study (NCT03090659) enrolled at the Xi'an site, analysing the first salvage line of therapy and outcomes in patients with RRMM who progressed after receiving LCAR-B38M CAR-T therapy. Of 45 eligible patients, 34 (76%) had progressive disease (PD). Overall response rate (ORR) to salvage treatment was 50.0%. Median progression-free survival (PFS) after starting salvage treatment was 16.3 months. Median PFS of patients receiving proteasome inhibitor (PI)-based combination therapy was longer (28.2 months) than that of patients receiving a second BCMA CAR-T (including LCAR-B38M; 3.9 months, p = 0.0022) or chemotherapy (1.67 months, p = 0.0001). All patients with extramedullary disease at baseline (n = 11) progressed after CAR-T therapy; ORR to salvage therapy was 25.0% and median PFS was 9.7 months. In conclusion, salvage therapy in patients with PD after receiving LCAR-B38M CAR-T cells produced moderate efficacy, with better outcomes for PI-based salvage regimens.
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Antígeno de Maturação de Linfócitos B , Imunoterapia Adotiva , Mieloma Múltiplo , Terapia de Salvação , Humanos , Mieloma Múltiplo/terapia , Mieloma Múltiplo/mortalidade , Terapia de Salvação/métodos , Masculino , Feminino , Pessoa de Meia-Idade , Estudos Retrospectivos , Imunoterapia Adotiva/efeitos adversos , Imunoterapia Adotiva/métodos , Idoso , Adulto , Resultado do TratamentoRESUMO
BACKGROUND & AIMS: Although small patient subsets benefit from current targeted strategies or immunotherapy, gemcitabine remains the first-line drug for pancreatic cancer (PC) treatment. However, gemcitabine resistance is widespread and compromises long-term survival. Here, we identified ubiquitin-conjugating enzyme E2T (UBE2T) as a potential therapeutic target to combat gemcitabine resistance in PC. METHODS: Proteomics and metabolomics were combined to examine the effect of UBE2T on pyrimidine metabolism remodeling. Spontaneous PC mice (LSL-KrasG12D/+, LSL-Trp53R172H/+, Pdx1-Cre; KPC) with Ube2t-conditional knockout, organoids, and large-scale clinical samples were used to determine the effect of UBE2T on gemcitabine efficacy. Organoids, patient-derived xenografts (PDX), and KPC mice were used to examine the efficacy of the combination of a UBE2T inhibitor and gemcitabine. RESULTS: Spontaneous PC mice with Ube2t deletion had a marked survival advantage after gemcitabine treatment, and UBE2T levels were positively correlated with gemcitabine resistance in clinical patients. Mechanistically, UBE2T catalyzes ring finger protein 1 (RING1)-mediated ubiquitination of p53 and relieves the transcriptional repression of ribonucleotide reductase subunits M1 and M2, resulting in unrestrained pyrimidine biosynthesis and alleviation of replication stress. Additionally, high-throughput compound library screening using organoids identified pentagalloylglucose (PGG) as a potent UBE2T inhibitor and gemcitabine sensitizer. The combination of gemcitabine and PGG diminished tumor growth in PDX models and prolonged long-term survival in spontaneous PC mice. CONCLUSIONS: Collectively, UBE2T-mediated p53 degradation confers PC gemcitabine resistance by promoting pyrimidine biosynthesis and alleviating replication stress. This study offers an opportunity to improve PC survival by targeting UBE2T and develop a promising gemcitabine sensitizer in clinical translation setting.
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Gencitabina , Neoplasias Pancreáticas , Humanos , Camundongos , Animais , Enzimas de Conjugação de Ubiquitina/genética , Enzimas de Conjugação de Ubiquitina/metabolismo , Proteína Supressora de Tumor p53/genética , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Modelos Animais de Doenças , Linhagem Celular Tumoral , Neoplasias PancreáticasRESUMO
N-type PbSe thermoelectric materials encounter challenges in improving the power factor due to the single-band structure near the Fermi level, which obstructs typical band convergence. The primary strategy for enhancing the thermoelectric figure of merit (ZT) for n-type PbSe involves reducing lattice thermal conductivity (κlat) by introducing various defect structures. However, lattice mismatches resulting from internal defects within the matrix can diminish carrier mobility, thereby affecting electrical transport properties. In this study, n-type AgCuTe-alloyed PbSe systems achieve a peak ZT value of ≈1.5 at 773 K. Transmission electron microscopy reveals nanoprecipitates of Ag2Te, the room temperature second phase of AgCuTe, within the PbSe matrix. Meanwhile, a unique semi-coherent phase boundary is observed between the PbSe matrix and the Ag2Te nanoprecipitates. This semi-coherent phase interface effectively scatters low-frequency phonons while minimizing damage to carrier mobility. Additionally, the dynamic doping effect of Cu atoms from the decomposition of AgCuTe within the matrix further optimize the high-temperature thermoelectric performance. Overall, these factors significantly enhance the ZT across the whole temperature range. The ZT value of ≈1.5 indicates high competitiveness compared to the latest reported n-type PbSe materials, suggesting that these findings hold promise for advancing the development of efficient thermoelectric systems.
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Acute myeloid leukemia (AML) is one of the most prevalent types of leukemia and is challenging to cure for most patients. Basic Leucine Zipper ATF-Like Transcription Factor (BATF) has been reported to participate in the development and progression of numerous tumors. However, its role in AML is largely unknown. In this study, the expression and prognostic value of BATF were examined in AML. Our results demonstrated that BATF expression was upregulated in AML patients, which was significantly correlated with poor clinical characteristics and survival. Afterward, functional experiments were performed after knocking down or overexpressing BATF by transfecting small interfering RNAs and overexpression plasmids into AML cells. Our findings revealed that BATF promoted the migratory and invasive abilities of AML cells in vitro and in vivo. Moreover, the target genes of BATF were searched from databases to explore the binding of BATF to the target gene using ChIP and luciferase assays. Notably, our observations validated that BATF is bound to the promoter region of TGF-ß1, which could transcriptionally enhance the expression of TGF-ß1 and activate the TGF-ß1/Smad/MMPs signaling pathway. In summary, our study established the aberrantly high expression of BATF and its pro-migratory function via the TGF-ß1-Smad2/3-MMP2/9 axis in AML, which provides novel insights into extramedullary infiltration of AML.
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Fatores de Transcrição de Zíper de Leucina Básica , Leucemia Mieloide Aguda , Fator de Crescimento Transformador beta1 , Animais , Feminino , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Fatores de Transcrição de Zíper de Leucina Básica/genética , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Regulação Leucêmica da Expressão Gênica , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patologia , Leucemia Mieloide Aguda/genética , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 9 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/genética , Invasividade Neoplásica , Prognóstico , Transdução de Sinais , Proteínas Smad/metabolismo , Proteínas Smad/genética , Fator de Crescimento Transformador beta1/metabolismo , Fator de Crescimento Transformador beta1/genéticaRESUMO
Ultralow thermal conductivity and fast ionic diffusion endow superionic materials with excellent performance both as thermoelectric converters and as solid-state electrolytes. Yet the correlation and interdependence between these two features remain unclear owing to a limited understanding of their complex atomic dynamics. Here we investigate ionic diffusion and lattice dynamics in argyrodite Ag8SnSe6 using synchrotron X-ray and neutron scattering techniques along with machine-learned molecular dynamics. We identify a critical interplay of the vibrational dynamics of mobile Ag and a host framework that controls the overdamping of low-energy Ag-dominated phonons into a quasi-elastic response, enabling superionicity. Concomitantly, the persistence of long-wavelength transverse acoustic phonons across the superionic transition challenges a proposed 'liquid-like thermal conduction' picture. Rather, a striking thermal broadening of low-energy phonons, starting even below 50 K, reveals extreme phonon anharmonicity and weak bonding as underlying features of the potential energy surface responsible for the ultralow thermal conductivity (<0.5 W m-1 K-1) and fast diffusion. Our results provide fundamental insights into the complex atomic dynamics in superionic materials for energy conversion and storage.
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Signaling via the T cell antigen receptor (TCR) during the CD4(+)CD8(+) double-positive developmental stage determines thymocyte selection and lineage commitment. Here we describe a previously uncharacterized T cell-expressed protein, Tespa1, with critical functions during the positive selection of thymocytes. Tespa1(-/-) mice had fewer mature thymic CD4(+) and CD8(+) T cells, which reflected impaired thymocyte development. Tespa1 associated with the TCR signaling components PLC-γ1 and Grb2, and Tespa1 deficiency resulted in attenuated TCR signaling, as reflected by defective activation of the Erk-AP-1 and Ca(2+)-NFAT pathways. Our findings demonstrate that Tespa1 is a component of the TCR signalosome and is essential for T cell selection and maturation through the regulation of TCR signaling during T cell development.
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Receptores de Antígenos de Linfócitos T/imunologia , Linfócitos T/imunologia , Timo/imunologia , Proteínas Adaptadoras de Transdução de Sinal/imunologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Diferenciação Celular/imunologia , Clonagem Molecular , Proteína Adaptadora GRB2/imunologia , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Dados de Sequência Molecular , Fosfolipase C gama/imunologia , RNA Mensageiro/química , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Alinhamento de Sequência , Transdução de Sinais/imunologia , Timo/citologiaRESUMO
The measurement accuracy of digital image correlation (DIC) is influenced by the quality of the speckle pattern. Although various models for generating random speckle patterns have been well discussed, obtaining appropriate speckle images with isotropic quality and performance could be a challenging issue in DIC. In this paper, we propose a novel (to our knowledge) method for generating speckle patterns based on modified Conway's game of life (GoL). By sequentially assembling the speckle patterns generated from the modified GoL, we produced the GoL speckle image. Then, verification and comparison experiments were conducted through pure in-plane translations. The results show that the generated speckle image which was resized with k s=6& k r=2 processing and subsequently fuzzified using a Gaussian filter, produces the best accuracy for DIC measurement. Furthermore, based on the rigid body in-plane rotation displacement tests in the physical experimental results of three different speckle images, the GoL speckle generated from our proposed method shows the smallest measurement error. This indicates that the proposed speckle patterns generating method could provide a new type of speckle pattern with better quality and accuracy.
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Bright daylight photon noise and the saturation of wavefront sensors pose challenges to high-resolution daytime imaging. In this paper, a daytime hybrid wavefront sensor (HyWFS) approach for real-time wavefront sensing in daylight adaptive optics (AO) is described. The Shack-Hartmann wavefront sensor (SHWFS) algorithm is used to efficiently compensate large-scale wavefronts, while the pyramid wavefront sensor (PyWFS) algorithm offers highly sensitive correction of small wavefronts. Daylight closed-loop AO experiments were performed using the daytime HyWFS approach with both algorithms, respectively. The experiment results indicate that the proposed approach provides accurate daylight AO correction and allows for a simple switch between the two algorithms without increasing system complexity. The daytime HyWFS approach can serve as an alternative for daylight natural guide star AO, enabling high-resolution observation of resident space objects no longer limited to dawn and dusk.
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Doxorubicin (Dox) is an anti-tumor drug with a broad spectrum, whereas the cardiotoxicity limits its further application. In clinical settings, liposome delivery vehicles are used to reduce Dox cardiotoxicity. Here, we substitute extracellular vesicles (EVs) for liposomes and deeply investigate the mechanism for EV-encapsulated Dox delivery. The results demonstrate that EVs dramatically increase import efficiency and anti-tumor effects of Dox in vitro and in vivo, and the efficiency increase benefits from its unique entry pattern. Dox-loading EVs repeat a "kiss-and-run" motion before EVs internalization. Once EVs touch the cell membrane, Dox disassociates from EVs and directly enters the cytoplasm, leading to higher and faster Dox import than single Dox. This unique entry pattern makes the adhesion between EVs and cell membrane rather than the total amount of EV internalization the key factor for regulating the Dox import. Furthermore, we recognize ICAM1 as the molecule mediating the adhesion between EVs and cell membranes. Interestingly, EV-encapsulated Dox can induce ICAM1 expression by irritating IFN-γ and TNF-α secretion in TME, thereby increasing tumor targeting of Dox-loading EVs. Altogether, EVs and EV-encapsulated Dox synergize via ICAM1, which collectively enhances the curative effects for tumor treatment.
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Antibióticos Antineoplásicos , Doxorrubicina , Vesículas Extracelulares , Molécula 1 de Adesão Intercelular , Doxorrubicina/farmacologia , Doxorrubicina/administração & dosagem , Animais , Humanos , Molécula 1 de Adesão Intercelular/metabolismo , Vesículas Extracelulares/metabolismo , Vesículas Extracelulares/efeitos dos fármacos , Antibióticos Antineoplásicos/farmacologia , Antibióticos Antineoplásicos/administração & dosagem , Linhagem Celular Tumoral , Camundongos Endogâmicos BALB C , Camundongos , Feminino , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Adesão Celular/efeitos dos fármacos , Sistemas de Liberação de Medicamentos , Camundongos Nus , Fator de Necrose Tumoral alfa/metabolismoRESUMO
Mammalian cells utilize Akt-dependent signaling to deploy intracellular Glut4 toward cell surface to facilitate glucose uptake. Low-density lipoprotein receptor (LDLR) is the cargo receptor mediating endocytosis of apolipoprotein B-containing lipoproteins. However, signaling-controlled regulation of intracellular LDLR trafficking remains elusive. Here, we describe a unique amino acid stress response, which directs the deployment of intracellular LDLRs, causing enhanced LDL endocytosis, likely via Ca2+ and calcium/calmodulin-dependent protein kinase II-mediated signalings. This response is independent of induction of autophagy. Amino acid stress-induced increase in LDL uptake in vitro is comparable to that by pravastatin. In vivo, acute AAS challenge for up to 72 h enhanced the rate of hepatic LDL uptake without changing the total expression level of LDLR. Reducing dietary amino acids by 50% for 2 to 4 weeks ameliorated high fat diet-induced hypercholesterolemia in heterozygous LDLR-deficient mice, with reductions in both LDL and VLDL fractions. We suggest that identification of signaling-controlled regulation of intracellular LDLR trafficking has advanced our understanding of the LDLR biology, and may benefit future development of additional therapeutic strategies for treating hypercholesterolemia.
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Aminoácidos , Receptores de LDL , Aminoácidos/metabolismo , Animais , Proteínas de Transporte/metabolismo , Endocitose , Lipoproteínas/metabolismo , Fígado/metabolismo , Camundongos , Receptores de LDL/genética , Receptores de LDL/metabolismoRESUMO
Sepsis, a life-threatening health issue, lacks effective medicine targeting the septic response. In China, treatment combining the intravenous herbal medicine XueBiJing with conventional procedures reduces the 28-day mortality of critically ill patients by modulating septic response. In this study, we identified the combined active constituents that are responsible for the XueBiJing's anti-sepsis action. Sepsis was induced in rats by cecal ligation and puncture (CLP). The compounds were identified based on their systemic exposure levels and anti-sepsis activities in CLP rats that were given an intravenous bolus dose of XueBiJing. Furthermore, the identified compounds in combination were assessed, by comparing with XueBiJing, for levels of primary therapeutic outcome, pharmacokinetic equivalence, and pharmacokinetic compatibility. We showed that a total of 12 XueBiJing compounds, unchanged or metabolized, circulated with significant systemic exposure in CLP rats that received XueBiJing. Among these compounds, hydroxysafflor yellow A, paeoniflorin, oxypaeoniflorin, albiflorin, senkyunolide I, and tanshinol displayed significant anti-sepsis activities, which involved regulating immune responses, inhibiting excessive inflammation, modulating hemostasis, and improving organ function. A combination of the six compounds, with the same respective doses as in XueBiJing, displayed percentage survival and systemic exposure in CLP rats similar to those by XueBiJing. Both the combination and XueBiJing showed high degrees of pharmacokinetic compatibility regarding interactions among the six active compounds and influences of other circulating XueBiJing compounds. The identification of XueBiJing's pharmacologically significant constituents supports the medicine's anti-sepsis use and provides insights into a polypharmacology-based approach to develop medicines for effective sepsis management.
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Medicamentos de Ervas Chinesas , Ratos Sprague-Dawley , Sepse , Animais , Sepse/tratamento farmacológico , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/administração & dosagem , Medicamentos de Ervas Chinesas/uso terapêutico , Medicamentos de Ervas Chinesas/farmacocinética , Masculino , Ratos , Administração IntravenosaRESUMO
OBJECTIVE: There is increasing interest in early intervention and detection strategies for youth at-risk of developing a serious mental illness (SMI). Little is known about early factors that may be related to the later development of a SMI; thus, the aim of this study was to determine what clinical factors might relate to the development of in this study psychosis, bipolar disorder and severe or recurrent major depression in at-risk youth. METHOD: The sample consisted of 162 youth aged 12-26 years at different stages of risk. Thirty-one participants developed a SMI during the study. Those who made a transition were compared on a range of baseline clinical and functional measures with those who did not make the transition. A Cox regression model was used to assess the association between measures and later development of a SMI. RESULTS: Female sex, attenuated psychotic symptoms as assessed with the Scale of Psychosis-Risk Symptoms (SOPS) and ratings on the K-10 Distress Scale, were found to be significantly associated with the later transition to mental illness. Females were 2.77 times more likely to transition compared to males. For the SOPS and K-10 scales, there is a 14% increase in the transition rate relative to a one-scale increase in SOPS and a 7% increase in the transition rate relative to a one-point increase in the K-10. CONCLUSIONS: Results from these longitudinal data provide further insight into the specific clinical measures that may be pertinent in early detection of mental illnesses.
Assuntos
Transtorno Bipolar , Transtorno Depressivo , Transtornos Mentais , Transtornos Psicóticos , Masculino , Adolescente , Humanos , Feminino , Transtornos Mentais/diagnóstico , Transtornos Mentais/epidemiologia , Transtornos Psicóticos/diagnóstico , Transtornos Psicóticos/epidemiologia , Transtorno Bipolar/diagnóstico , Transtorno Bipolar/epidemiologiaRESUMO
BACKGROUND: Emergency psychiatric care, unplanned hospital admissions, and inpatient health care are the costliest forms of mental health care. According to Statistics Canada (2018), almost 18% (5.3 million) of Canadians reported needing mental health support. However, just above half of this figure (56.2%) have reported their needs were fully met. In light of this evidence there is a pressing need to provide accessible mental health services in flexible yet cost-effective ways. To further expand capacity and access to mental health care in the province, Nova Scotia Health has launched a novel mental health initiative for people in need of mental health care without requiring emergency department visits or hospitalization. This new service is referred to as the Rapid Access and Stabilization Program (RASP). This study evaluates the effectiveness and impact of the RASP on high-cost health services utilization (e.g. ED visits, mobile crisis visits, and inpatient treatments) and related costs. It also assesses healthcare partners' (e.g. healthcare providers, policymakers, community leaders) perceptions and patient experiences and satisfaction with the program and identifies sociodemographic characteristics, psychological conditions, recovery, well-being, and risk measures in the assisted population. METHOD: This is a hypothesis-driven program evaluation study that employs a mixed methods approach. A within-subject comparison (pre- and post-evaluation study) will examine health services utilization data from patients attending RASP, one year before and one year after their psychiatry assessment at the program. A controlled between-subject comparison (cohort study) will use historical data from a control population will examine whether possible changes in high-cost health services utilization are associated with the intervention (RASP). The primary analysis involves extracting secondary data from provincial information systems, electronic medical records, and regular self-reported clinical assessments. Additionally, a qualitative sub-study will examine patient experience and satisfaction, and health care partners' impressions. DISCUSSION: We expect that RASP evaluation findings will demonstrate a minimum 10% reduction in high-cost health services utilization and corresponding 10% cost savings, and also a reduction in the wait times for patient consultations with psychiatrists to less than 30 calendar days, in both within-subject and between-subject comparisons. In addition, we anticipate that patients, healthcare providers and healthcare partners would express high levels of satisfaction with the new service. CONCLUSION: This study will demonstrate the results of the Mental Health and Addictions Program (MHAP) efforts to provide stepped-care, particularly community-based support, to individuals with mental illnesses. Results will provide new insights into a novel community-based approach to mental health service delivery and contribute to knowledge on how to implement mental health programs across varying contexts.