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1.
Nat Immunol ; 24(1): 96-109, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36510022

RESUMO

Immune aging combines cellular defects in adaptive immunity with the activation of pathways causing a low-inflammatory state. Here we examined the influence of age on the kinetic changes in the epigenomic and transcriptional landscape induced by T cell receptor (TCR) stimulation in naive CD4+ T cells. Despite attenuated TCR signaling in older adults, TCR activation accelerated remodeling of the epigenome and induced transcription factor networks favoring effector cell differentiation. We identified increased phosphorylation of STAT5, at least in part due to aberrant IL-2 receptor and lower HELIOS expression, as upstream regulators. Human HELIOS-deficient, naive CD4+ T cells, when transferred into human-synovium-mouse chimeras, infiltrated tissues more efficiently. Inhibition of IL-2 or STAT5 activity in T cell responses of older adults restored the epigenetic response pattern to the one seen in young adults. In summary, reduced HELIOS expression in non-regulatory naive CD4+ T cells in older adults directs T cell fate decisions toward inflammatory effector cells that infiltrate tissue.


Assuntos
Envelhecimento , Linfócitos T CD4-Positivos , Fator de Transcrição Ikaros , Idoso , Animais , Humanos , Camundongos , Adulto Jovem , Envelhecimento/imunologia , Envelhecimento/patologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/patologia , Montagem e Desmontagem da Cromatina , Ativação Linfocitária , Receptores de Antígenos de Linfócitos T , Fator de Transcrição STAT5 , Fator de Transcrição Ikaros/metabolismo
2.
Small ; 19(43): e2303186, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37365955

RESUMO

With the advent of intelligent society and the popularity of electronic equipment, the protection and treatment of electromagnetic (EM) radiation have become hot research topics all over the world. Herein, novel 2D carbon-based nanoplates with uniformly embedded Co nanoparticles are prepared, with unique hierarchical structure and integrated magnetic-dielectric components. The obtained hierarchical nanoplates exhibit a wide range of tunable EM properties (ε' for 3.38 to 34.67 and ε″ for 0.13 to 31.45) by manipulating the dispersed states inside wax system, which can achieve an effective switch from microwave absorption to EM interference shielding performance. The optimal reflection loss reaches -55.6 dB, and the shielding efficiency is 93.5%. Meanwhile, the hierarchical nanoplates also exhibit impressive capacitive performance, with a specific capacitance of 1654 F g-1 at 1 A g-1 . Based on this, a creative device is constructed with the nanoplates, which can convert harmful EM radiation to useful electric energy for recycling. This work offers a new idea for the development of EM materials and functional devices, powerfully promoting the advance of energy and environmental fields.

3.
Proc Natl Acad Sci U S A ; 117(1): 532-540, 2020 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-31879353

RESUMO

The T cell repertoire in each individual includes T cell receptors (TCRs) of enormous sequence diversity through the pairing of diverse TCR α- and ß-chains, each generated by somatic recombination of paralogous gene segments. Whether the TCR repertoire contributes to susceptibility to infectious or autoimmune diseases in concert with disease-associated major histocompatibility complex (MHC) polymorphisms is unknown. Due to a lack in high-throughput technologies to sequence TCR α-ß pairs, current studies on whether the TCR repertoire is shaped by host genetics have so far relied only on single-chain analysis. Using a high-throughput single T cell sequencing technology, we obtained the largest paired TCRαß dataset so far, comprising 965,523 clonotypes from 15 healthy individuals including 6 monozygotic twin pairs. Public TCR α- and, to a lesser extent, TCR ß-chain sequences were common in all individuals. In contrast, sharing of entirely identical TCRαß amino acid sequences was very infrequent in unrelated individuals, but highly increased in twins, in particular in CD4 memory T cells. Based on nucleotide sequence identity, a subset of these shared clonotypes appeared to be the progeny of T cells that had been generated during fetal development and had persisted for more than 50 y. Additional shared TCRαß in twins were encoded by different nucleotide sequences, implying that genetic determinants impose structural constraints on thymic selection that favor the selection of TCR α-ß pairs with entire sequence identities.


Assuntos
Receptores de Antígenos de Linfócitos T alfa-beta/genética , Gêmeos Monozigóticos/genética , Adulto , Sequência de Aminoácidos/genética , Sequência de Bases/genética , Linfócitos T CD4-Positivos/metabolismo , Conjuntos de Dados como Assunto , Feminino , Antígenos HLA/genética , Antígenos HLA/metabolismo , Sequenciamento de Nucleotídeos em Larga Escala , Teste de Histocompatibilidade , Humanos , Memória Imunológica , Masculino , Pessoa de Meia-Idade , Modelos Genéticos , Receptores de Antígenos de Linfócitos T alfa-beta/metabolismo , Análise de Sequência de DNA , Análise de Célula Única
4.
J Am Chem Soc ; 144(45): 20825-20833, 2022 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-36318653

RESUMO

Thioredoxin reductase (TrxR) is highly overexpressed in cancer cells to promote malignant tumor survival. Designing drugs that inhibit TrxR activity is a promising approach to achieve highly effective cancer chemotherapy. However, the selectivity of TrxR inhibitors continue to be a challenge for scientists. In this work, we demonstrate a new strategy to selectively inhibit TrxR through constructing electrophilic center -N-Se(δ+)-N- by using the polarization effect of the selenium atom. The constructed electrophilic center interacts noncovalently with the active motif of TrxR to avoid the interference of other residues in human tissues, thereby selectively inhibiting intracellular TrxR activity. Computational and experimental analysis confirms that the formed electrophilic selenium center preferred to attack the SeC residues in the redox active center of TrxR at the 498 site through strong noncovalent interactions. Both in vitro and in vivo experimental results confirmed that this strategy can significantly improve the anticancer effect. This study may provide a novel route to design highly effective and selective chemotherapeutic drugs.


Assuntos
Neoplasias , Selênio , Humanos , Tiorredoxina Dissulfeto Redutase , Selênio/farmacologia , Neoplasias/tratamento farmacológico , Oxirredução , Antioxidantes
5.
Molecules ; 27(15)2022 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-35956890

RESUMO

Inappropriate and disproportionate antibiotic use contributes immensely to the development of antibiotic resistance in bacterial species associated with food contamination. Therefore, alternative strategies to treat multidrug-resistant (MDR) bacterial infections are urgently needed. In this study, verbascoside was shown to exhibit excellent antibacterial activity and synergistic effects in combination with cell wall synthesis-inhibiting antibiotics, indicating that it can be used as an adjuvant to restore or increase the activity of antibiotics against resistant pathogens. In a mechanistic study, higher concentrations of verbascoside resulted in a longer lag phase and a lower specific exponential-phase growth rate of bacteria. Furthermore, verbascoside exerted its antimicrobial activity through multiple mechanisms, including cell membrane dysfunction, biofilm eradication and changes in cell morphology. The promising antibacterial activity and in vitro safety assessment results suggested that verbascoside can be used as a food additive for fresh meat preservation. Treatment with medium and high doses of verbascoside caused significant bacterial death in meat samples, slowed the spoilage rate, and extended the shelf life. Collectively, verbascoside is expected to be useful as an antibiotic adjuvant to prevent or treat resistant bacteria-related infections and an alternative novel antimicrobial additive in the food industry.


Assuntos
Antibacterianos , Carne , Antibacterianos/farmacologia , Bactérias , Farmacorresistência Bacteriana Múltipla , Glucosídeos , Carne/microbiologia , Testes de Sensibilidade Microbiana , Fenóis
6.
Nanotechnology ; 32(44)2021 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-34320474

RESUMO

Ti3C2Txis an important member of the MXenes family. Due to its excellent electrical conductivity, adjustable atomic layer, and modifiable active surface, Ti3C2Txhas attracted great attention in the field of electromagnetic interference (EMI) shielding. This paper introduces the important role of regulating conductive network to improve the EMI shielding performance of materials and summarizes the EMI shielding performance of Ti3C2Txnanohybrids reported in recent years. In addition, Ti3C2Txbased EMI shielding materials towards multifunctional devices are also systematically introduced. After that, the development status of Ti3C2Txnanohybrids in the field of EMI shielding is objectively described, and the main problems and challenges are evaluated. Finally, the prospect of Ti3C2Txnanohybrids for advanced and green EMI shielding materials is forecasted.

7.
Luminescence ; 36(2): 316-325, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32845573

RESUMO

Self-activated Ca5 Mg3 Zn(VO4 )6 and Ca5 Mg3 Zn(VO4 )6 :xEu3+ phosphors were synthesized via a high-temperature solid-state reaction route. The crystalline structure and luminescence properties of the phosphors were analyzed using an X-ray diffractometer and a photoluminescence spectrometer. The explored results indicated that by varying calcination temperature and the raw material ratio of Ca2+ /Mg2+ /Zn2+ , the phosphors could be developed with different phases, crystallinity, and various fluorescence performances. The fluorescence spectrum of Ca5 Mg3 Zn(VO4 )6 showed a broad emission band over the range 400-650 nm under an excitation wavelength of 330 nm, as well as green light emission. Furthermore, after introduction of Eu3+ ions in Eu(VO4 )4 , the luminescence intensity of the Eu3+ ions greatly increased as the Eu3+ ion concentration increased at the 393 nm excitation wavelength, showing green-yellow light emission simultaneously. Therefore, the obtained phosphors could be used as a potential green-yellow-emitting luminescent material in a white light-emitting diode device.


Assuntos
Európio , Luminescência , Temperatura , Zinco
8.
Pharm Biol ; 58(1): 72-79, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31875760

RESUMO

Context: Cisplatin-based chemotherapy was widely used in treating human malignancies. However, side effects and chemoresistance remains the major obstacle.Objective: To verify whether natural borneol (NB) can enhance cisplatin-induced glioma cell apoptosis and explore the mechanism.Materials and methods: Cytotoxicity of cisplatin and/or NB towards U251 and U87 cells were determined with the MTT assay. Cells were treated with 0.25-80 µg/mL cisplatin and/or 5-80 µM NB for 48 h. The effects of NB and/or cisplatin on apoptosis and cell cycle distribution were quantified by flow cytometric analysis. Protein expression was detected by western blotting. ROS generation was conducted by measuring and visualising an oxidation-sensitive fluorescein DCFH-DA.Results: NB synergistically enhanced the anticancer efficacy of cisplatin in human glioma cells. Co-treatment of 40 µg/mL NB and 40 µg/mL cisplatin significantly inhibited U251 cell viability from 100% to 28.2% and increased the sub-G1 population from 1.4% to 59.3%. Further detection revealed that NB enhanced cisplatin-induced apoptosis by activating caspases and triggering reactive oxygen species (ROS) overproduction as evidenced by the enhancement of green fluorescence intensity from 265% to 645%. ROS-mediated DNA damage was observed as reflected by the activation of ATM/ATR, p53 and histone. Moreover, MAPKs and PI3K/AKT pathways also contributed to co-treatment-induced U251 cell growth inhibition. ROS inhibition by antioxidants effectively improved MAPKs and PI3K/AKT functions and cell viability, indicating that NB enhanced cisplatin-induced cell growth in a ROS-dependent manner.Discussion and conclusions: Natural borneol had the potential to sensitise human glioma cells to cisplatin-induced apoptosis with potential application in the clinic.


Assuntos
Antineoplásicos/farmacologia , Canfanos/farmacologia , Cisplatino/farmacologia , Glioma/tratamento farmacológico , Antineoplásicos/administração & dosagem , Apoptose/efeitos dos fármacos , Canfanos/administração & dosagem , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cisplatino/administração & dosagem , Dano ao DNA/efeitos dos fármacos , Relação Dose-Resposta a Droga , Resistencia a Medicamentos Antineoplásicos , Glioma/patologia , Humanos , Estresse Oxidativo/efeitos dos fármacos , Fosfatidilinositol 3-Quinase/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espécies Reativas de Oxigênio/metabolismo
9.
Small ; : e1800987, 2018 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-29882284

RESUMO

Electromagnetic energy radiation is becoming a "health-killer" of living bodies, especially around industrial transformer substation and electricity pylon. Harvesting, converting, and storing waste energy for recycling are considered the ideal ways to control electromagnetic radiation. However, heat-generation and temperature-rising with performance degradation remain big problems. Herein, graphene-silica xerogel is dissected hierarchically from functions to "genes," thermally driven relaxation and charge transport, experimentally and theoretically, demonstrating a competitive synergy on energy conversion. A generic approach of "material genes sequencing" is proposed, tactfully transforming the negative effects of heat energy to superiority for switching self-powered and self-circulated electromagnetic devices, beneficial for waste energy harvesting, conversion, and storage. Graphene networks with "well-sequencing genes" (w = Pc /Pp > 0.2) can serve as nanogenerators, thermally promoting electromagnetic wave absorption by 250%, with broadened bandwidth covering the whole investigated frequency. This finding of nonionic energy conversion opens up an unexpected horizon for converting, storing, and reusing waste electromagnetic energy, providing the most promising way for governing electromagnetic pollution with self-powered and self-circulated electromagnetic devices.

11.
Nanotechnology ; 27(6): 065702, 2016 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-26685017

RESUMO

Tuning microwave absorption to meet the harsh requirement of thermal environments is a great challenge. Three kinds of nanowires, including multi-walled carbon nanotubes (MWCNTs) coated with CdS nanocrystals (CdS-MWCNTs), and MWCNTs coated with different-thickness CdS sheaths, have been synthesized through mild solution-process synthesis. The influence of CdS amount, external temperature, loading concentration and sample thickness on the absorption performance were studied. The composite loading with 6 vol.% CdS-MWCNTs shows the best absorption of -47 dB at 473 K with a thickness of 2.6 mm in the temperature range of 323-573 K and X band. The effective bandwidth covers the full X band in 323-473 K for RL ≤ -20 dB and reaches 2.0 GHz at 473 K for RL ≤ -20 dB. The enhanced absorption ability of CdS-MWCNTs arises from the effective impedance matching, benefiting from abundant interfacial polarization from the added CdS nanocrystals and the changeable dielectric property at elevated temperature. The results indicate that the CdS-MWCNT is a promising functional material for high temperature microwave absorption.

12.
Eur J Immunol ; 43(1): 258-69, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23065757

RESUMO

Bone marrow-derived macrophages (BMMs) treated with granulocyte-macrophage colony-stimulating factor (GM-CSF) or macrophage colony-stimulating factor (M-CSF), differentiate into GM-CSF-induced mouse bone marrow-derived macrophages (GM-BMMs) or M-CSF-induced mouse bone marrow-derived macrophages (M-BMMs), which have an M1 or M2 profile, respectively. GM-BMMs produce large amounts of proinflammatory cytokines and mediate resistance to pathogens, whereas M-BMMs produce antiinflammatory cytokines that contribute to tissue repair and remodeling. M-BMMs stimulated with lipopolysaccharide (LPS) are in an antiinflammatory state, with an IL-12(low) IL-10(high) phenotype. However, the regulation of this process remains unclear. Klf10 belongs to the family of Krüppel-like transcription factors and was initially described as a TGF-ß inducible early gene 1. IL-12p40 is upregulated in LPS-stimulated M-BMMs from Klf10-deficient mice, but downregulated during Klf10 overexpression. Klf11, another member of the Krüppel-like factor family, can also repress the production of IL-12p40. Furthermore, Klf10 binds to the CACCC element of the IL-12p40 promoter and inhibits its transcription. We have therefore identified Klf10 as a transcription factor that regulates the expression of IL-12p40 in M-BMMs.


Assuntos
Células da Medula Óssea/imunologia , Fatores de Transcrição de Resposta de Crescimento Precoce/metabolismo , Subunidade p40 da Interleucina-12/metabolismo , Fatores de Transcrição Kruppel-Like/metabolismo , Macrófagos/imunologia , Animais , Diferenciação Celular , Células Cultivadas , Citocinas/metabolismo , Fatores de Transcrição de Resposta de Crescimento Precoce/genética , Fatores de Transcrição de Resposta de Crescimento Precoce/imunologia , Regulação da Expressão Gênica/genética , Mediadores da Inflamação/metabolismo , Subunidade p40 da Interleucina-12/genética , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/imunologia , Fator Estimulador de Colônias de Macrófagos/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Regiões Promotoras Genéticas/genética , Transcrição Gênica/imunologia , Transgenes/genética
13.
Artigo em Inglês | MEDLINE | ID: mdl-38837922

RESUMO

Flocking control of autonomous underwater vehicles (AUVs) has been regarded as the basis of many sophisticated marine coordination missions. However, there is still a research gap on the flocking of AUVs in weak communication and complex marine environment. This article attempts to fill up the above research gap from graph theory and intelligent learning perspectives. We first employ the bearing rigidity graph to describe the topology relationships of AUVs, through which an iterative gradient decent-based localization estimator is provided to obtain the position information. In order to improve the localization accuracy and energy efficiency, a min-weighted bearing rigidity graph generation strategy is developed. Along with this, we adopt the semi-supervised broad learning system (BLS) to design the model-free flocking controllers for AUVs in obstacle environment. The innovations of this article are summarized as follows: 1) the min-weighted bearing rigidity-based localization strategy can balance the localization accuracy and communication consumption as compared to the neighboring rule-based solutions and 2) the semi-supervised broad learning-based flocking controller can decrease the training time and solve the label limit over the supervised learning-based controllers. Finally, simulation and experimental studies are provided to verify the effectiveness.

14.
Nanomicro Lett ; 16(1): 173, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38619642

RESUMO

With the diversified development of big data, detection and precision guidance technologies, electromagnetic (EM) functional materials and devices serving multiple spectrums have become a hot topic. Exploring the multispectral response of materials is a challenging and meaningful scientific question. In this study, MXene/TiO2 hybrids with tunable conduction loss and polarization relaxation are fabricated by in situ atomic reconstruction engineering. More importantly, MXene/TiO2 hybrids exhibit adjustable spectral responses in the GHz, infrared and visible spectrums, and several EM devices are constructed based on this. An antenna array provides excellent EM energy harvesting in multiple microwave bands, with |S11| up to - 63.2 dB, and can be tuned by the degree of bending. An ultra-wideband bandpass filter realizes a passband of about 5.4 GHz and effectively suppresses the transmission of EM signals in the stopband. An infrared stealth device has an emissivity of less than 0.2 in the infrared spectrum at wavelengths of 6-14 µm. This work can provide new inspiration for the design and development of multifunctional, multi-spectrum EM devices.

15.
Bioact Mater ; 37: 393-406, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38689659

RESUMO

Radiation-induced heart disease (RIHD), characterized by severe oxidative stress and immune dysregulation, is a serious condition affecting cancer patients undergoing thoracic radiation. Unfortunately, clinical interventions for RIHD are lacking. Selenium (Se) is a trace element with excellent antioxidant and immune-modulatory properties. However, its application in heart radioprotection remains challenging. Herein, we developed a novel bioactive Cordyceps militaris-based Se oral delivery system (Se@CM), which demonstrated superior radioprotection effects in vitro against X-ray-induced damage in H9C2 cells through suppressing excessive ROS generation, compared to the radioprotectant Amifostine. Moreover, Se@CM exhibited exceptional cardioprotective effects in vivo against X-ray irradiation, reducing cardiac dysfunction and myocardial fibrosis by balancing the redox equilibrium and modulating the expression of Mn-SOD and MDA. Additionally, Se@CM maintained immuno-homeostasis, as evidenced by the upregulated population of T cells and M2 macrophages through modulation of selenoprotein expression after irradiation. Together, these results highlight the remarkable antioxidant and immunity modulation properties of Se@CM and shed light on its promising application for cardiac protection against IR-induced disease. This research provides valuable insights into developing effective strategies for preventing and managing RIHD.

16.
Adv Sci (Weinh) ; 10(26): e2302361, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37431193

RESUMO

Lightweight and flexible electronic materials with high energy attenuation hold an unassailable position in electromagnetic stealth and intelligent devices. Among them, emerging heterodimensional structure draws intensive attention in the frontiers of materials, chemistry, and electronics, owing to the unique electronic, magnetic, thermal, and optical properties. Herein, an intrinsic heterodimensional structure consisting of alternating assembly of 0D magnetic clusters and 2D conductive layers is developed, and its macroscopic electromagnetic properties are flexibly designed by customizing the number of oxidative molecular layer deposition (oMLD) cycles. This unique heterodimensional structure features highly ordered spatial distribution, with an achievement of electron-dipole and magnetic-dielectric double synergies, which exhibits the high attenuation of electromagnetic energy (160) and substantial improvement of dielectric loss tangent (≈200%). It can respond to electromagnetic waves of different bands to achieve multispectral stealth, covering visible light, infrared radiation, and gigahertz wave. Importantly, two kinds of ingenious information interaction devices are constructed with heterodimensional structure. The hierarchical antennas allow precise targeting of operating bands (S- to Ku- bands) by oMLD cycles. The strain imaging device with high sensitivity opens a new horizon for visual interaction. This work provides a creative insight for developing advanced micro-nano materials and intelligent devices.

17.
Zookeys ; 1168: 151-159, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37415717

RESUMO

The known species of the genus Norellisoma from China are reviewed and two new species from Yintiaoling Nature Reserve in Chongqing City, where no other Norellisoma species are recorded, are described: Norellisomawuxiensesp. nov., Norellisomayintiaoensesp. nov. A key to the species of Norellisoma from China is provided.

18.
Front Immunol ; 14: 1154699, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37081887

RESUMO

The brain has long been considered an immune-privileged organ due to the presence of the blood-brain barrier (BBB). However, recent discoveries have revealed the underestimated role of T cells in the brain through the meningeal lymphatic system. Age is the primary risk factor for Alzheimer's disease (AD), resulting in marked age-dependent changes in T cells. Manipulating peripheral T cell immune response has been shown to impact AD, but the relationship between T cell aging and AD remains poorly understood. Given the limited success of targeting amyloid beta (Aß) and the growing evidence of T cells' involvement in non-lymphoid organ aging, a deeper understanding of the relationship between T cells and AD in the context of aging is crucial for advancing therapeutic progress. In this review, we comprehensively examine existing studies on T cells and AD and offer an integrated perspective on their interconnections in the context of aging. This understanding can inform the development of new interventions to prevent or treat AD.


Assuntos
Doença de Alzheimer , Humanos , Doença de Alzheimer/etiologia , Peptídeos beta-Amiloides , Linfócitos T , Envelhecimento , Senescência Celular
19.
Biomed Pharmacother ; 160: 114326, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36736279

RESUMO

Osteoporosis is a common disease of the elderly that affects millions of patients worldwide. It is mainly characterized by low bone mineral density and increased risk of fracture due to the deterioration of the bone structure, leading to difficulties in functional recovery, reduced quality of life, increased disability risk and mortality in the population. It has already been a major public health problem. Osteoporosis is a chronic disease that is difficult to treat in the elderly population, so it is crucial to develop new drugs for the treatment of osteoporosis. Oleoyl serine, an endogenous fatty acyl amide found in bone, has been shown to have excellent anti-osteoporosis effects, but it is easily hydrolyzed by amidases in vivo. The aim of this study is to determine the anti-osteoporotic effect of calcium-derived oleoyl serine, a novel oleoyl serine derivative and the molecular mechanism underneath. In vitro experiments demonstrated that calcium-derived oleoyl serine suppressed the expression of Fabp4, and Cebpα while Alp, and Runx2 was significantly upregulated compared with the oleoyl serine group and control. With the activation of ß-catenin, calcium-derived oleoyl serine restored the abnormal osteogenesis and lipogenesis, indicating calcium-derived oleoyl serine compared with oleoyl serine has better effects on promoting osteogenesis and suppressing lipogenesis. In vivo experiment agreed with these findings that calcium-derived oleoyl serine promotes osteogenesis and suppresses its lipogenesis to ameliorate osteoporosis via a ß-catenin dependent method. It is a new candidate for treating osteoporosis.


Assuntos
Cálcio , Osteoporose , Idoso , Humanos , Cálcio/farmacologia , beta Catenina/metabolismo , Serina/farmacologia , Serina/uso terapêutico , Qualidade de Vida , Osteoporose/metabolismo , Via de Sinalização Wnt , Osteogênese , Diferenciação Celular
20.
Cell Rep ; 42(3): 112195, 2023 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-36884349

RESUMO

Naive CD4+ T cells are more resistant to age-related loss than naive CD8+ T cells, suggesting mechanisms that preferentially protect naive CD4+ T cells during aging. Here, we show that TRIB2 is more abundant in naive CD4+ than CD8+ T cells and counteracts quiescence exit by suppressing AKT activation. TRIB2 deficiency increases AKT activity and accelerates proliferation and differentiation in response to interleukin-7 (IL-7) in humans and during lymphopenia in mice. TRIB2 transcription is controlled by the lineage-determining transcription factors ThPOK and RUNX3. Ablation of Zbtb7b (encoding ThPOK) and Cbfb (obligatory RUNT cofactor) attenuates the difference in lymphopenia-induced proliferation between naive CD4+ and CD8+ cells. In older adults, ThPOK and TRIB2 expression wanes in naive CD4+ T cells, causing loss of naivety. These findings assign TRIB2 a key role in regulating T cell homeostasis and provide a model to explain the lesser resilience of CD8+ T cells to undergo changes with age.


Assuntos
Linfócitos T CD8-Positivos , Linfopenia , Idoso , Animais , Humanos , Camundongos , Envelhecimento , Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Diferenciação Celular , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Homeostase , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fatores de Transcrição/metabolismo
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