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1.
Immunity ; 57(6): 1289-1305.e9, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38772366

RESUMO

Adipose tissue group 2 innate lymphoid cells (ILC2s) help maintain metabolic homeostasis by sustaining type 2 immunity and promoting adipose beiging. Although impairment of the ILC2 compartment contributes to obesity-associated insulin resistance, the underlying mechanisms have not been elucidated. Here, we found that ILC2s in obese mice and humans exhibited impaired liver kinase B1 (LKB1) activation. Genetic ablation of LKB1 disrupted ILC2 mitochondrial metabolism and suppressed ILC2 responses, resulting in exacerbated insulin resistance. Mechanistically, LKB1 deficiency induced aberrant PD-1 expression through activation of NFAT, which in turn enhanced mitophagy by suppressing Bcl-xL expression. Blockade of PD-1 restored the normal functions of ILC2s and reversed obesity-induced insulin resistance in mice. Collectively, these data present the LKB1-PD-1 axis as a promising therapeutic target for the treatment of metabolic disease.


Assuntos
Tecido Adiposo , Homeostase , Resistência à Insulina , Linfócitos , Mitocôndrias , Obesidade , Receptor de Morte Celular Programada 1 , Proteínas Serina-Treonina Quinases , Animais , Resistência à Insulina/imunologia , Receptor de Morte Celular Programada 1/metabolismo , Camundongos , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Serina-Treonina Quinases/genética , Mitocôndrias/metabolismo , Humanos , Tecido Adiposo/metabolismo , Tecido Adiposo/imunologia , Obesidade/imunologia , Obesidade/metabolismo , Linfócitos/imunologia , Linfócitos/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Imunidade Inata , Masculino , Mitofagia/imunologia , Quinases Proteína-Quinases Ativadas por AMP
2.
Artigo em Inglês | MEDLINE | ID: mdl-38940785

RESUMO

Background: Stroke is a major cause of long-term disability in adults. Routine nursing mainly meets the life needs of patients through the intervention of patients' general life but only provides the most basic services for patients, which makes it difficult to meet the requirements of patients' physical exercise and other aspects, affecting the prognosis. Early rehabilitation after a stroke is important for the recovery of bodily functions in stroke patients. However, the impacts of early rehabilitation nursing on motor function, swallowing function as well as quality of life in stroke patients remain to be further explored. Objective: To investigate the effects of early rehabilitation nursing on motor function, swallowing function as well as quality of life in stroke patients. Design: This was a randomized, single-blind, controlled experiment. Setting: This study was carried out in the neurology department at Xuzhou Central Hospital. Participants: A total of 116 acute stroke patients validated by craniocerebral computed tomography (CT) and magnetic resonance imaging (MRI) from January 2021 to December 2022 were chosen and separated into the control group (n=58) and research group (n=58) following the random number method. Interventions: The control group was given routine nursing. The research group implemented early rehabilitation nursing 24 hours after admission on the basis of the control group. Primary Outcome Measures: (1) recovery of swallowing dysfunction (2) recovery of limb function (3) self-care ability (4) sleep quality (5) quality of life and (6) total satisfaction of patients. Results: The research group had an elevated total effective rate of swallowing dysfunction recovery in contrast to the control group after nursing (P < .05). The recovery of limb function, self-care ability, sleep quality, and quality of life were promoted in both groups, followed by nursing (P < .05), and those in the research group were higher relative to the control group (P < .05). The total satisfaction of patients in the research group presented higher relative to the control group (P < .05). Conclusion: The application effect of early rehabilitation nursing in acute stroke patients is outstanding, and the swallowing dysfunction and limb dysfunction of patients can be effectively improved, which has a high nursing value and is worth promoting and applying. Therefore, an early physical rehabilitation program for acute stroke inpatients should be considered for implementation in clinical settings.

3.
Nano Lett ; 23(8): 3309-3316, 2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-36946560

RESUMO

Integrating single atoms and clusters into one system is a novel strategy to achieve desired catalytic performances. Compared with homogeneous single-atom cluster catalysts, heterogeneous ones combine the merits of different species and therefore show greater potential. However, it is still challenging to construct single-atom cluster systems of heterogeneous species, and the underlying mechanism for activity improvement remains unclear. In this work, we developed a heterogeneous single-atom cluster catalyst (ConIr1/N-C) for efficient oxygen evolution. The Ir single atoms worked in synergy with the Co clusters at a distance of about 8 Å, which optimized the configuration of the key intermediates. Consequently, the oxygen evolution activity was significantly improved on ConIr1/N-C relative to the Co cluster catalyst (Con/N-C), exhibiting an overpotential lower by 107 mV than that of Con/N-C at 10 mA cm-2 and a turnover frequency 50.9 times as much as that of Con/N-C at an overpotential of 300 mV.

4.
BMC Biol ; 20(1): 287, 2022 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-36528592

RESUMO

BACKGROUND: Inflammatory bowel diseases (IBDs) are characterized by sustained inflammation and/or ulcers along the lower digestive tract, and have complications such as colorectal cancer and inflammation in other organs. The current treatments for IBDs, which affect 0.3% of the global population, mainly target immune cells and inflammatory cytokines with a success rate of less than 40%. RESULTS: Here we show that berberine, a natural plant product, is more effective than the frontline drug sulfasalazine in treating DSS (dextran sulfate sodium)-induced colitis in mice, and that berberine not only suppresses macrophage and granulocyte activation but also promotes epithelial restitution by activating Lgr5+ intestinal stem cells (ISCs). Mechanistically, berberine increases the expression of Wnt genes in resident mesenchymal stromal cells, an ISC niche, and inhibiting Wnt secretion diminishes the therapeutic effects of berberine. We further show that berberine controls the expression of many circadian rhythm genes in stromal cells, which in turn regulate the expression of Wnt molecules. CONCLUSIONS: Our findings suggest that berberine acts on the resident stromal cells and ISCs to promote epithelial repair in experimental colitis and that Wnt-ß-Catenin signaling may be a potential target for colitis treatment.


Assuntos
Berberina , Colite , Camundongos , Animais , Berberina/farmacologia , Berberina/uso terapêutico , Sulfato de Dextrana/efeitos adversos , Modelos Animais de Doenças , Colite/induzido quimicamente , Colite/tratamento farmacológico , Células-Tronco/metabolismo , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Mucosa Intestinal/metabolismo
5.
J Am Chem Soc ; 144(21): 9271-9279, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35549330

RESUMO

The two-dimensional surface or one-dimensional interface of heterogeneous catalysts is essential to determine the adsorption strengths and configurations of the reaction intermediates for desired activities. Recently, the development of single-atom catalysts has enabled an atomic-level understanding of catalytic processes. However, it remains obscure whether the conventional concept and mechanism of one-dimensional interface are applicable to zero-dimensional single atoms. In this work, we arranged the locations of single atoms to explore their interfacial interactions for improved oxygen evolution. When iridium single atoms were confined into the lattice of CoOOH, efficient electron transfer between Ir and Co tuned the adsorption strength of oxygenated intermediates. In contrast, atomic iridium species anchored on the surface of CoOOH induced inappreciable modification in electronic structures, whereas steric interactions with key intermediates at its Ir-OH-Co interface played a primary role in reducing its energy barrier toward oxygen evolution.

6.
Nano Lett ; 21(11): 4795-4801, 2021 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-34018755

RESUMO

Oxygen evolution reaction (OER) plays an important role in renewable energy supplies as the anodic reaction for electrochemical transformation of various chemicals. Iron-based OER catalysts are potential candidates due to their abundance but suffer from poor activity. Here we demonstrate that a single-atom iron catalyst with in-situ generated Fe4+ centers is highly active toward OER. Only an overpotential of 320 mV was needed to reach 10 mA cm-2. The catalyst exhibited an ultrahigh turnover frequency of 0.62 s-1 at an overpotential of 0.35 V, which is comparable to currently reported transitional-metal based OER catalysts. Experimental and theoretical studies revealed that the valence state of the metal center transferred from Fe3+ to highly active Fe4+ prior to the OER process. This transformation was originated from the strong interaction between atomic Fe and carbon support via C-O-Fe bonding, leading to a lower energy barrier of the rate-limiting *OOH formation.

7.
Toxicol Appl Pharmacol ; 378: 114612, 2019 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-31175881

RESUMO

Infertility caused by environmental pollution is becoming a global problem, but an effective prevention or treatment is lacking. Icariin (ICA) is a flavonoid used in traditional Chinese medicine. The present study investigated the possible roles of ICA in preventing testicular dysfunction caused by di(2-ethylhexyl) phthalate (DEHP), one of the most studied environmental endocrine disruptors. Cultured mouse Leydig cells were pretreated with ICA and exposed to DEHP to determine ICA effects upon cell proliferation, reactive oxygen species (ROS) levels, mitochondrial membrane potential (Δψm), testosterone levels and the expression of transcription factor SF-1 and steroidogenic enzymes (CYP11, 3ß-HSD and 17ß-HSD), which play critical roles in androgen production. Our results showed that ICA reversed the adverse effect of DEHP on Leydig cell proliferation, and decreased ROS levels and elevated Δψm levels. Also, ICA promoted testosterone production and up-regulated the expression of SF-1 and steroidogenic enzymes. We investigated ICA actions in vivo, using male mice administrated DEHP followed by ICA. Exposure to DEHP decreased epididymal sperm counts and disrupted seminiferous tubules, and both of these effects were reversed by ICA treatment. These results showed that the mechanisms of ICA in protecting mouse testes against DEHP-induced damage involves the prevention of ROS accumulation and promotion of testosterone secretion.


Assuntos
Dietilexilftalato/efeitos adversos , Flavonoides/farmacologia , Células Intersticiais do Testículo/efeitos dos fármacos , Ácidos Ftálicos/efeitos adversos , Substâncias Protetoras/farmacologia , Testosterona/metabolismo , Animais , Proliferação de Células/efeitos dos fármacos , Disruptores Endócrinos/metabolismo , Feminino , Células Intersticiais do Testículo/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos ICR , Gravidez , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Espermatozoides/efeitos dos fármacos , Espermatozoides/metabolismo , Testículo/efeitos dos fármacos , Testículo/metabolismo
8.
Cell Rep ; 43(5): 113579, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38670109

RESUMO

Group 2 innate lymphoid cells (ILC2s) play crucial roles in mediating allergic inflammation. Recent studies also indicate their involvement in regulating tumor immunity. The tumor suppressor liver kinase B1 (LKB1) inactivating mutations are associated with a variety of human cancers; however, the role of LKB1 in ILC2 function and ILC2-mediated tumor immunity remains unknown. Here, we show that ablation of LKB1 in ILC2s results in an exhausted-like phenotype, which promotes the development of lung melanoma metastasis. Mechanistically, LKB1 deficiency leads to a marked increase in the expression of programmed cell death protein-1 (PD-1) in ILC2s through the activation of the nuclear factor of activated T cell pathway. Blockade of PD-1 can restore the effector functions of LKB1-deficient ILC2s, leading to enhanced antitumor immune responses in vivo. Together, our results reveal that LKB1 acts to restrain the exhausted state of ILC2 to maintain immune homeostasis and antitumor immunity.


Assuntos
Proteínas Quinases Ativadas por AMP , Imunidade Inata , Linfócitos , Camundongos Endogâmicos C57BL , Proteínas Serina-Treonina Quinases , Animais , Proteínas Serina-Treonina Quinases/metabolismo , Camundongos , Linfócitos/imunologia , Linfócitos/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/patologia , Receptor de Morte Celular Programada 1/metabolismo , Humanos , Linhagem Celular Tumoral , Melanoma/imunologia , Melanoma/patologia
9.
Cell Mol Immunol ; 20(4): 379-388, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36693920

RESUMO

Group 3 innate lymphoid cells (ILC3s) play important roles in maintaining intestinal homeostasis by protecting the host from pathogen infections and tissue inflammation. The transcription factor PLZF (promyelocytic leukemia zinc finger), encoded by zinc finger BTB domain containing 16 (Zbtb16), is highly and transiently expressed in ILC precursors (ILCPs). However, the role of PLZF in regulating ILC3 development and function remains unknown. Here, we show that PLZF was specifically expressed in mature intestinal ILC3s compared with other ILC subsets. PLZF was dispensable for ILC3 development. However, PLZF deficiency in ILC3s resulted in increased innate interleukin-22 (IL-22) secretion and protection against gut infection and inflammation. Mechanistically, PLZF negatively regulated IL-22 expression by ILC3s in a cell-intrinsic manner by binding to the IL-22 promoter region for transcriptional repression. Together, our data suggest that PLZF restricts intestinal ILC3 function to regulate gut immune homeostasis.


Assuntos
Imunidade Inata , Linfócitos , Proteína com Dedos de Zinco da Leucemia Promielocítica , Humanos , Expressão Gênica , Inflamação/metabolismo , Fatores de Transcrição/metabolismo , Proteína com Dedos de Zinco da Leucemia Promielocítica/metabolismo
10.
Nat Commun ; 13(1): 2473, 2022 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-35513390

RESUMO

The homogeneity of single-atom catalysts is only to the first-order approximation when all isolated metal centers interact identically with the support. Since the realistic support with various topologies or defects offers diverse coordination environments, realizing real homogeneity requires precise control over the anchoring sites. In this work, we selectively anchor Ir single atoms onto the three-fold hollow sites (Ir1/TO-CoOOH) and oxygen vacancies (Ir1/VO-CoOOH) on defective CoOOH surface to investigate how the anchoring sites modulate catalytic performance. The oxygen evolution activities of Ir1/TO-CoOOH and Ir1/VO-CoOOH are improved relative to CoOOH through different mechanisms. For Ir1/TO-CoOOH, the strong electronic interaction between single-atom Ir and the support modifies the electronic structure of the active center for stronger electronic affinity to intermediates. For Ir1/VO-CoOOH, a hydrogen bonding is formed between the coordinated oxygen of single-atom Ir center and the oxygenated intermediates, which stabilizes the intermediates and lowers the energy barrier of the rate-determining step.

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