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1.
Nature ; 600(7888): 314-318, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34819664

RESUMO

Thermogenesis in brown and beige adipose tissue has important roles in maintaining body temperature and countering the development of metabolic disorders such as obesity and type 2 diabetes1,2. Although much is known about commitment and activation of brown and beige adipose tissue, its multiple and abundant immunological factors have not been well characterized3-6. Here we define a critical role of IL-27-IL-27Rα signalling in improving thermogenesis, protecting against diet-induced obesity and ameliorating insulin resistance. Mechanistic studies demonstrate that IL-27 directly targets adipocytes, activating p38 MAPK-PGC-1α signalling and stimulating the production of UCP1. Notably, therapeutic administration of IL-27 ameliorated metabolic morbidities in well-established mouse models of obesity. Consistently, individuals with obesity show significantly decreased levels of serum IL-27, which can be restored after bariatric surgery. Collectively, these findings show that IL-27 has an important role in orchestrating metabolic programs, and is a highly promising target for anti-obesity immunotherapy.


Assuntos
Adipócitos/metabolismo , Metabolismo Energético , Interleucina-27/metabolismo , Termogênese , Animais , Cirurgia Bariátrica , Modelos Animais de Doenças , Feminino , Humanos , Resistência à Insulina , Interleucina-27/sangue , Interleucina-27/uso terapêutico , Masculino , Camundongos , Obesidade/sangue , Obesidade/tratamento farmacológico , Obesidade/metabolismo , Obesidade/prevenção & controle , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Receptores de Interleucina/metabolismo , Transdução de Sinais , Proteína Desacopladora 1/biossíntese , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
2.
Brain Behav Immun ; 89: 615-622, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32688026

RESUMO

BACKGROUND: Systemic inflammation and immune dysregulation have been considered as risk factors in the pathophysiology of mood disorders including bipolar disorder (BD). Previous neuroimaging studies have demonstrated metabolic, structural and functional abnormalities in the insula in BD, proposed that the insula played an important role in BD. We herein aimed to explore neural mechanisms underlying inflammation-induced in the insular subregions functional connectivity (FC) in patients with BD. METHODS: Brain resting-state functional magnetic resonance imaging (rs-fMRI) data were acquired from 41 patients with unmedicated BD II (current episode depressed), 68 healthy controls (HCs). Three pairs of insular seed regions were selected: the bilateral anterior insula (AI), the bilateral middle insula (MI) and the bilateral posterior insula (PI), and calculated the whole-brain FC for each subregion. Additionally, the serum levels of pro-inflammatory cytokines in patients and HCs, including IL-6 and TNF-α, were detected. Then the partial correlation coefficients between the abnormal insular subregions FC values and pro-inflammatory cytokines levels in patients with BD II depression were calculated. RESULTS: The BD II depression group exhibited decreased FC between the right PI and the left postcentral gyrus, and increased FC between the left AI and the bilateral insula (extended to the right putamen) when compared with the HC group. Moreover, the patients with BD II depression showed higher IL-6 and TNF-α levels than HCs, and IL-6 level was negatively correlated with FC of the right PI to the left postcentral gyrus. CONCLUSIONS: Our results demonstrated that abnormal FC between the bilateral insula, and between the insula and sensorimotor areas in BD. Moreover, disrupted FC between the insula and sensorimotor areas was associated with elevated pro-inflammatory cytokine levels of IL-6 in BD.


Assuntos
Transtorno Bipolar , Transtorno Bipolar/diagnóstico por imagem , Córtex Cerebral/diagnóstico por imagem , Humanos , Inflamação/diagnóstico por imagem , Imageamento por Ressonância Magnética , Neuroimagem
3.
J Cell Physiol ; 234(9): 16178-16190, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30786006

RESUMO

Ovarian cancer resistance to available medicines is a huge challenge in dire need of a solution, which makes its recurrence and mortality rate further exacerbated. A promising approach to overcome chemoresistance is drug screening from natural products. Here, we report that NK007, a (±)-tylophorine malate isolated from the Asclepiadaceae family, selectively inhibited the proliferation of A2780 and A2780 (Taxol) cells and migration of paclitaxel-sensitive and -resistant ovarian cancer cells. Interestingly, the decline of cell viability, including cell multiplication, clonality, and migration capacity was independent on cell apoptosis. At the molecular level, NK007 considerably induced G1/S arrest and upregulated the expression of phospho-p38 mitogen-activated protein kinase (p-p38MAPK). In addition, hexokinase 2 (HK2) protein degradation was considerably elevated in the presence of NK007, which resulted in the reduction of oxygen consumption rate and extracellular acidification rate. Altogether, our results indicate that NK007, an analog of tylophorine, can overcome paclitaxel (PTX) resistance through p38MAPK activation and HK2 degradation. As an effective, alternative antiresistance agent, NK007 exhibits a promising potential to treat PTX-resistant ovarian cancer.

4.
J Cancer ; 15(13): 4386-4405, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38947398

RESUMO

Background: TMEM132A is a transmembrane protein that regulates gastric cancer cell malignancy and overall survival in bladder cancer patients. However, while some studies have investigated the involvement of TMEM132A in specific cancers, further systematic studies are required to elucidate its specific mechanisms of action in different cancer types. Methods: We investigated the pan-cancer role of TMEM132A using several databases. We analyzed TMEM132A expression and its correlation with clinical survival, immune checkpoints, tumor stemness score, prognostic value, immunomodulators, genomic profiles, immunological characteristics, immunotherapy and functional enrichment. Results: First, it was observed that TMEM132A expression levels were higher in the majority of tumors compared to non-tumor tissues. In addition, high TMEM132A expression may have a higher prognostic value in some cancers. Furthermore, TMEM132A was significantly associated with immune checkpoints, immunomodulators, prognosis, immunomodulatory genes, tumor stemness score, cell function status and immune infiltration in most tumors. Further analysis of TMEM132A-related gene enrichment, mutation sites and types, RNA modification and genomic heterogeneity showed that the major mutations of TMEM132A were missense mutations and that TMEM132A plays a very important role in UCEC, LUAD and LIHC. Finally, these results suggest that high TMEM132A expression may be associated with a better response to specific immunotherapies. Conclusion: This comprehensive study uncovers an important function for TMEM132A in different types of cancer. It also has the potential to identify TMEM132A as a potential biomarker for predicting treatment response. This may help us to better understand how TMEM132A plays a role in cancer and provide valuable insights for developing personalised treatments.

5.
Transl Psychiatry ; 14(1): 292, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39013880

RESUMO

Accumulating evidence has revealed the gut bacteria dysbiosis and brain hippocampal functional and structural alterations in major depressive disorder (MDD). However, the potential relationship between the gut microbiota and hippocampal function alterations in patients with MDD is still very limited. Data of resting-state functional magnetic resonance imaging were acquired from 44 unmedicated MDD patients and 42 demographically matched healthy controls (HCs). Severn pairs of hippocampus subregions (the bilateral cornu ammonis [CA1-CA3], dentate gyrus (DG), entorhinal cortex, hippocampal-amygdaloid transition area, and subiculum) were selected as the seeds in the functional connectivity (FC) analysis. Additionally, fecal samples of participants were collected and 16S rDNA amplicon sequencing was used to identify the altered relative abundance of gut microbiota. Then, association analysis was conducted to investigate the potential relationships between the abnormal hippocampal subregions FC and microbiome features. Also, the altered hippocampal subregion FC values and gut microbiota levels were used as features separately or together in the support vector machine models distinguishing the MDD patients and HCs. Compared with HCs, patients with MDD exhibited increased FC between the left hippocampus (CA2, CA3 and DG) and right hippocampus (CA2 and CA3), and decreased FC between the right hippocampal CA3 and bilateral posterior cingulate cortex. In addition, we found that the level of proinflammatory bacteria (i.e., Enterobacteriaceae) was significantly increased, whereas the level of short-chain fatty acids producing-bacteria (i.e., Prevotellaceae, Agathobacter and Clostridium) were significantly decreased in MDD patients. Furthermore, FC values of the left hippocampal CA3- right hippocampus (CA2 and CA3) was positively correlated with the relative abundance of Enterobacteriaceae in patients with MDD. Moreover, altered hippocampal FC patterns and gut microbiota level were considered in combination, the best discrimination was obtained (AUC = 0.92). These findings may provide insights into the potential role of gut microbiota in the underlying neuropathology of MDD patients.


Assuntos
Transtorno Depressivo Maior , Microbioma Gastrointestinal , Hipocampo , Imageamento por Ressonância Magnética , Humanos , Transtorno Depressivo Maior/microbiologia , Transtorno Depressivo Maior/fisiopatologia , Transtorno Depressivo Maior/diagnóstico por imagem , Masculino , Hipocampo/fisiopatologia , Hipocampo/diagnóstico por imagem , Hipocampo/microbiologia , Adulto , Feminino , Disbiose/microbiologia , Disbiose/fisiopatologia , Adulto Jovem , Estudos de Casos e Controles , Pessoa de Meia-Idade , Fezes/microbiologia
6.
Parasit Vectors ; 17(1): 44, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38291478

RESUMO

BACKGROUND: Systemic lupus erythematosus (SLE) is a complex systemic autoimmune disease characterized by the presence of numerous autoantibodies. The interaction of infectious agents (viruses, bacteria and parasites) and a genetically susceptible host may be a key mechanism for SLE. Toxoplasma gondii is a widespread intracellular parasite that has been implicated in the pathogenesis of autoimmune diseases. However, the relationship between T. gondii infection and the increased risk of SLE in Chinese populations remains unclear. METHODS: The seroprevalence of T. gondii infection was assessed in 1771 serum samples collected from Chinese individuals (908 healthy controls and 863 SLE patients) from different regions of China using an enzyme-linked immunosorbent assay. Serum autoantibodies and clinical information were obtained and analysed. RESULTS: Our observations revealed a higher prevalence of anti-T. gondii antibodies (ATxA) immunoglobulin G (IgG) in serum samples from SLE patients (144/863, 16.7%) than in those from the healthy controls (53/917, 5.8%; P < 0.0001), indicating a 2.48-fold increased risk of SLE in the ATxA-IgG+ population, after adjustment for age and sex (95% confidence interval [CI] 1.70-3.62, P < 0.0001). ATxA-IgG+ SLE patients also showed a 1.75-fold higher risk of developing moderate and severe lupus symptoms (95% CI 1.14-2.70, P = 0.011) compared to ATxA-IgG- patients. Relative to ATxA-IgG- patients, ATxA-IgG+ patients were more likely to develop specific clinical symptoms, including discoid rash, oral ulcer, myalgia and alopecia. Seven antibodies, namely anti-ribosomal RNA protein (rRNP), anti-double stranded DNA (dsDNA), anti-cell membrane DNA (cmDNA), anti-scleroderma-70 (Scl-70), anti-cardiolipin (CL), anti-beta2-glycoprotein-I (B2GPI) and rheumatoid factor (RF), occurred more frequently in ATxA-IgG+ patients. When combined with anti-dsDNA and RF/anti-rRNP/anti-cmDNA/ESR, ATxA-IgG significantly increased the risk for severe lupus. CONCLUSIONS: Our results suggest that ATxA-IgG may be a significant risk factor for SLE prevalence and severity in Chinese populations.


Assuntos
Autoanticorpos , Lúpus Eritematoso Sistêmico , Humanos , Estudos Soroepidemiológicos , Prevalência , Lúpus Eritematoso Sistêmico/complicações , Lúpus Eritematoso Sistêmico/epidemiologia , Imunoglobulina G , Fatores de Risco , DNA
7.
Cell Death Dis ; 15(7): 491, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38982043

RESUMO

IL-17+ γδ T cells (γδ T17) are kick-starters of inflammation due to their strict immunosurveillance of xenobiotics or cellular damages and rapid response to pro-inflammatory stimulators. IL-27 is a well-recognized pleiotropic immune regulator with potent inhibitory effects on type 17 immune responses. However, its actions on γδ T17 mediated inflammation and the underlying mechanisms are less well understood. Here we find that IL-27 inhibits the production of IL-17 from γδ T cells. Mechanistically, IL-27 promotes lipolysis while inhibits lipogenesis, thus reduces the accumulation of lipids and subsequent membrane phospholipids, which leads to mitochondrial deactivation and ensuing reduction of IL-17. More importantly, Il27ra deficient γδ T cells are more pathogenic in an imiquimod-induced murine psoriasis model, while intracutaneous injection of rmIL-27 ameliorates psoriatic inflammation. In summary, this work uncovered the metabolic basis for the immune regulatory activity of IL-27 in restraining γδ T17 mediated inflammation, which provides novel insights into IL-27/IL-27Ra signaling, γδ T17 biology and the pathogenesis of psoriasis.


Assuntos
Interleucina-17 , Metabolismo dos Lipídeos , Mitocôndrias , Psoríase , Animais , Mitocôndrias/metabolismo , Camundongos , Psoríase/patologia , Psoríase/imunologia , Psoríase/metabolismo , Interleucina-17/metabolismo , Camundongos Endogâmicos C57BL , Inflamação/patologia , Inflamação/metabolismo , Pele/patologia , Pele/metabolismo , Pele/imunologia , Pele/efeitos dos fármacos , Modelos Animais de Doenças , Receptores de Antígenos de Linfócitos T gama-delta/metabolismo , Transdução de Sinais , Humanos
8.
Acta Pharm Sin B ; 13(9): 3930-3944, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37719372

RESUMO

Interleukin (IL)-17A, a pro-inflammatory cytokine, is a fundamental function in the onset and advancement of multiple immune diseases. To uncover the primary compounds with IL-17A inhibitory activity, a large-scale screening of the library of traditional Chinese medicine constituents and microbial secondary metabolites was conducted using splenic cells from IL-17A-GFP reporter mice cultured under Th17-priming conditions. Our results indicated that some aureane-type sesquiterpene tetraketides isolated from a wetland mud-derived fungus, Myrothecium gramineum, showed remarkable IL-17A inhibitory activity. Nine new aureane-type sesquiterpene tetraketides, myrogramins A-I (1, 4-11), and two known ones (2 and 3) were isolated and identified from the strain. Compounds 1, 3, 4, 10, and 11 exhibited significant IL-17A inhibitory activity. Among them, compound 3, with a high fermentation yield dose-dependently inhibited the generation of IL-17A and suppressed glycolysis in splenic cells under Th17-priming conditions. Strikingly, compound 3 suppressed immunopathology in both IL-17A-mediated animal models of experimental autoimmune encephalomyelitis and pulmonary hypertension. Our results revealed that aureane-type sesquiterpene tetraketides are a novel class of immunomodulators with IL-17A inhibitory activity, and hold great promise applications in treating IL-17A-mediated immune diseases.

9.
J Virol ; 84(18): 9359-68, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20592080

RESUMO

Human immunodeficiency virus type 1 (HIV-1) gp41 plays a critical role in the viral fusion process, and its N- and C-terminal heptad repeat domains serve as important targets for developing anti-HIV-1 drugs, like T-20 (generic name, enfuvirtide; brand name, Fuzeon). Here, we conducted a yeast two-hybrid screening on a human bone marrow cDNA library using the recombinant soluble gp41 ectodomain as the bait and identified a novel gp41 core-binding molecule, designated P20. P20 showed no homology with a current HIV fusion inhibitor, T-20, but had sequence homology to a human protein, troponin I type 3 interacting kinase (TNNI3K)-like protein. While it could bind to the six-helix bundle core structure formed by the N- and C-terminal heptad repeats, P20 did not interrupt the formation of the six-helix bundle. P20 was effective in blocking HIV-1 Env-mediated syncytium formation and inhibiting infection by a broad spectrum of HIV-1 strains with distinct subtypes and coreceptor tropism, while it was ineffective against other enveloped viruses, such as vesicular stomatitis virus and influenza A virus. P20 exhibited no significant cytotoxicity to the CD4(+) cells that were used for testing antiviral activity. Among the 11 P20 mutants, four analogous peptides with a common motif (WGRLEGRRT) exhibited significantly reduced anti-HIV-1 activity, suggesting that this region is the critical active site of P20. Therefore, this peptide can be used as a lead for developing novel HIV fusion inhibitors and as a probe for studying the membrane-fusogenic mechanism of HIV.


Assuntos
Proteína gp41 do Envelope de HIV/metabolismo , Inibidores da Fusão de HIV/isolamento & purificação , HIV-1/fisiologia , Interações Hospedeiro-Patógeno , MAP Quinase Quinase Quinases/genética , Peptídeos/isolamento & purificação , Internalização do Vírus , Sequência de Aminoácidos , Linfócitos T CD4-Positivos/virologia , Células Cultivadas , HIV-1/imunologia , Humanos , Dados de Sequência Molecular , Peptídeos/genética , Ligação Proteica , Proteínas Serina-Treonina Quinases , Homologia de Sequência de Aminoácidos , Técnicas do Sistema de Duplo-Híbrido
10.
Biomed Res Int ; 2021: 5554991, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34337024

RESUMO

BACKGROUND: Obesity is a main contributing factor for the development of glucose intolerance and type 2 diabetes mellitus (T2D). Roux-en-Y gastric bypass (RYGB) is believed to be one of the most effective treatments to reduce body weight and improve glucose metabolism. In this study, we sought to explore the underlying mechanisms of weight reduction and insulin resistance improvement after RYGB. METHODS: This was a prospective observational study using consecutive samples of 14 obese subjects undergoing bariatric surgery. Main assessments were serum indexes (blood metabolites, glucose-lipid regulating hormones, trimethylamine-N-oxide (TMAO), and lipopolysaccharide-binding protein (LBP), fecal short-chain fatty acids (SCFAs), and gut microbiota. Correlation analysis of the factors changed by RYGB was used to indicate the potential mechanism by which surgery improves insulin resistance. RESULTS: The subjects showed significant improvement on indices of obesity and insulin resistance and a correlated change of gut microbiota components at 1 month, 3 months, and 6 months post-RYGB operation. In particular, the abundance of a counterobese strain, Akkemansia muciniphila, had gradually increased with the postoperative time. Moreover, these changes were negatively correlated to serum levels of LBP and positively correlated to serum TMAO and fecal SCFAs. CONCLUSIONS: Our findings uncovered links between intestinal microbiota alterations, circulating endotoxemia, and insulin resistance. This suggests that the underlying mechanism of protection of the intestine by RYGB in obesity may be through changing the gut microbiota.


Assuntos
Endotoxemia/microbiologia , Endotoxemia/cirurgia , Derivação Gástrica , Microbioma Gastrointestinal , Resistência à Insulina , Proteínas de Fase Aguda/metabolismo , Proteínas de Transporte/metabolismo , Regulação para Baixo , Humanos , Glicoproteínas de Membrana/metabolismo , Metaboloma , Metilaminas/metabolismo , Obesidade/microbiologia , Obesidade/cirurgia
11.
Front Immunol ; 12: 686676, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34163485

RESUMO

During pregnancy, the maternal immune system undergoes major adaptive modifications that are necessary for the acceptance and protection of the fetus. It has been postulated that these modifications are temporary and limited to the time of pregnancy. Growing evidence suggests that pregnancy has a long-term impact on maternal health, especially among women with pregnancy complications, such as preeclampsia (PE). In addition, the presence of multiple immunological-associated changes in women that remain long after delivery has been reported. To explain these long-term modifications, we hypothesized that pregnancy induces long-term immunological memory with effects on maternal well-being. To test this hypothesis, we evaluated the immunological phenotype of circulating immune cells in women at least 1 year after a normal pregnancy and after pregnancy complicated by PE. Using multiparameter flow cytometry (FCM) and whole-genome bisulfite sequencing (WGBS), we demonstrate that pregnancy has a long-term effect on the maternal immune cell populations and that this effect differs between normal pregnancy and pregnancy complicated by PE; furthermore, these modifications are due to changes in the maternal methylation status of genes that are associated with T cell and NK cell differentiation and function. We propose the existence of an "immunological memory of pregnancy (IMOP)" as an evolutionary advantage for the success of future pregnancies and the proper adaptation to the microchimeric status established during pregnancy. Our findings demonstrate that the type of immune cell populations modified during pregnancy may have an impact on subsequent pregnancy and future maternal health.


Assuntos
Epigênese Genética/fisiologia , Memória Imunológica/fisiologia , Células Matadoras Naturais/fisiologia , Pré-Eclâmpsia/fisiopatologia , Complicações na Gravidez/fisiopatologia , Adaptação Fisiológica/fisiologia , Adulto , Decídua/imunologia , Feminino , Citometria de Fluxo , Humanos , Metilação , Paridade/fisiologia , Pré-Eclâmpsia/genética , Pré-Eclâmpsia/imunologia , Gravidez , Complicações na Gravidez/genética , Complicações na Gravidez/imunologia , Resultado da Gravidez , Sequenciamento Completo do Genoma , Adulto Jovem
12.
Aging (Albany NY) ; 12(3): 2840-2856, 2020 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-32074508

RESUMO

Uric acid is a common metabolite found in mammals' serum. Recently, several metabolites have been identified that modulate aging, and uric acid levels are positively correlated with mammals' lifespan. However, the molecular mechanisms underlying this are largely undefined. Here we show that uric acid, an end product of purine metabolism, enhances the resistance of oxidative stress and extends the life span of Caenorhabditis elegans (C. elegans). We show that uric acid enhances a variety of pathways and leads to the upregulation of genes that are required for uric acid-mediated life span extension. We find that the transcription factors DAF-16/FOXO, SKN-1/NRF2 and HSF-1 contribute to the beneficial longevity conferred by uric acid. We also show that uric acid induced life span extension by regulating the reproductive signaling and insulin/IGF-1 signaling (IIS) pathways. In addition, we find that mitochondrial function plays an important role in uric acid-mediated life span extension. Taken together, these data suggest that uric acid prolongs the life span of C. elegans, in part, because of its antioxidative activity, which in turn regulates the IIS and the reproductive signaling pathways, thereby activating the function of the transcription factors DAF-16, HSF-1 and SKN-1.


Assuntos
Proteínas de Caenorhabditis elegans/metabolismo , Proteínas de Ligação a DNA/metabolismo , Fatores de Transcrição Forkhead/metabolismo , Longevidade/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Fisiológico/efeitos dos fármacos , Fatores de Transcrição/metabolismo , Ácido Úrico/farmacologia , Animais , Caenorhabditis elegans , Proteínas de Caenorhabditis elegans/genética , Proteínas de Ligação a DNA/genética , Fatores de Transcrição Forkhead/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Herbicidas/toxicidade , Fator 2 Relacionado a NF-E2/genética , Paraquat/toxicidade , Fatores de Transcrição/genética
13.
Front Immunol ; 11: 846, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32528465

RESUMO

Non-alcoholic fatty liver disease (NAFLD) is one of the main causes of cirrhosis and major risk factors for hepatocellular carcinoma and liver-related death. Despite substantial clinical and basic research, the pathogenesis of obesity-related NAFLD remains poorly understood. In this study, we show that perforin can act as an immune regulator to prevent the progression of NAFLD. Aged perforin-deficient (Prf-/-) mice have increased lipid accumulation in the liver compared to WT mice. With high-fat diet (HFD) challenge, Prf-/- mice have increased liver weight, more severe liver damage, and increased liver inflammation when compared with WT controls. Mechanistic studies revealed that perforin specifically regulates intrinsic IFN-γ production in CD4 T cells, not CD8 T cells. We found that CD4 T cell depletion reduces liver injury and ameliorates the inflammation and metabolic morbidities in Prf-/- mice. Furthermore, improved liver characteristics in HFD Prf-/- and IFN-γR-/- double knockout mice confirmed that IFN-γ is a key factor for mediating perforin regulation of NAFLD progression. Overall, our findings reveal the important regulatory role perforin plays in the progression of obesity-related NAFLD and highlight novel strategies for treating NAFLD.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Progressão da Doença , Interferon gama/metabolismo , Hepatopatia Gordurosa não Alcoólica/imunologia , Perforina/metabolismo , Animais , Linfócitos T CD8-Positivos/imunologia , Dieta Hiperlipídica/efeitos adversos , Modelos Animais de Doenças , Hepatite/etiologia , Interferon gama/genética , Metabolismo dos Lipídeos/genética , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Hepatopatia Gordurosa não Alcoólica/sangue , Obesidade/metabolismo , Perforina/deficiência , Perforina/genética
14.
Cell Death Differ ; 27(7): 2248-2262, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32001780

RESUMO

The metabolism-controlled differentiation of αß T cells has been well documented; however, the role of a metabolism program in γδ T cell differentiation and function has not been clarified. Here, using CD2-cre; mTORC1 Raptor-f/f, and mTORC2 Rictor-f/f mice (KO mice), we found that mTORC1, but not mTORC2, was required for the proliferation and survival of peripheral γδ T cells, especially Vγ4 γδ T cells. Moreover, mTORC1 was essential for both γδ T1 and γδ Τ17 differentiation, whereas mTORC2 was required for γδ T17, but not for γδ Τ1, differentiation. We further studied the underlying molecular mechanisms and found that depletion of mTORC1 resulted in the increased expression of SOCS1, which in turn suppressed the key transcription factor Eomes, consequentially reducing IFN-γ production. Whereas the reduced glycolysis resulted in impaired γδ Τ17 differentiation in Raptor KO γδ T cells. In contrast, mTORC2 potentiated γδ Τ17 induction by suppressing mitochondrial ROS (mitoROS) production. Consistent with their cytokine production profiles, the Raptor KO γδ T cells lost their anti-tumor function both in vitro and in vivo, whereas both Raptor and Rictor KO mice were resistant to imiquimod (IMQ)-induced psoriasis-like skin pathogenesis. In summary, we identified previously unknown functions of mTORC1 and mTORC2 in γδ T cell differentiation and clarified their divergent roles in mediating the activity of γδ T cells in tumors and autoimmunity.


Assuntos
Diferenciação Celular , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Alvo Mecanístico do Complexo 2 de Rapamicina/metabolismo , Receptores de Antígenos de Linfócitos T gama-delta/metabolismo , Células Th1/citologia , Células Th1/imunologia , Células Th17/citologia , Células Th17/imunologia , Animais , Modelos Animais de Doenças , Glicólise , Interferon gama/biossíntese , Contagem de Linfócitos , Camundongos Knockout , Subfamília K de Receptores Semelhantes a Lectina de Células NK/metabolismo , Neoplasias/imunologia , Psoríase/patologia , Proteína Regulatória Associada a mTOR/deficiência , Proteína Regulatória Associada a mTOR/metabolismo , Transdução de Sinais , Proteína 1 Supressora da Sinalização de Citocina/metabolismo , Proteínas com Domínio T/metabolismo , Regulação para Cima
15.
Aging (Albany NY) ; 11(12): 3993-4010, 2019 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-31232697

RESUMO

The pyrimidine metabolism pathway has important biological functions; it not only maintains appropriate pyrimidine pools but also produces bioactive intermediate metabolites. In a previous study, we identified that the pyrimidine metabolism pathway is associated with aging regulation. However, the molecular mechanism by which the pyrimidine metabolism pathway regulates aging remains unclear. Here, we investigated the longevity effect of pyrimidine intermediates on Caenorhabditis elegans (C. elegans). Our results demonstrated that the supplementation of some pyrimidine intermediates could extend the lifespan of C. elegans. In addition, the RNAi knockdown of essential enzymes involved in pyrimidine metabolism could also significantly affect lifespan. We further investigated the molecular mechanism by which a representative intermediate metabolite, thymine, extends the lifespan of worms and found that thymine-induced longevity required the nuclear receptors DAF-12 and NHR-49, and the transcription factor DAF-16/FOXO. Further pathway analysis revealed that the longevity effect of thymine depended on the inhibition of reproductive signals. Additionally, we found that other pyrimidine intermediates functioned in a manner similar to thymine to prolong lifespan in C. elegans. Taken together, our results revealed that pyrimidine intermediates increased lifespan by inhibiting reproductive signals and subsequently inducing the function of DAF-12, NHR-49 and DAF-16 in C. elegans.


Assuntos
Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/fisiologia , Longevidade/fisiologia , Pirimidinas/metabolismo , Animais , Proteínas de Caenorhabditis elegans/genética , Regulação da Expressão Gênica/fisiologia , Interferência de RNA , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reprodução
16.
Biochem J ; 403(3): 565-71, 2007 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-17223796

RESUMO

The HIV-1 gp41 (glycoprotein 41) core plays a critical role in fusion between the viral and target cell membranes. We previously identified a gp41 core-binding motif, HXXNPF, by screening the phage display peptide libraries. In the present study, we elucidated the mechanism of action of HXXNPF motif-containing molecules of different sizes, including the phage clone L7.8 (a selected positive phage clone), L7.8-g3p* (a 10-kDa fragment of the gene 3 protein) and JCH-4 (a peptide containing 13 residues of L7.8-g3p*), regarding their respective binding abilities to the six-helix bundle and inhibition on syncytium formation at different temperatures. We found that all of the HXXNPF motif-containing molecules could bind to the gp41 core, and that their binding sites may be located in the N-helix domain. L7.8-g3p* and JCH-4 effectively inhibited HIV-1 Env (envelope glycoprotein)-mediated syncytium formation at 37 degrees C, while the phage clone L7.8 showed no inhibition under the same conditions. However, at suboptimal temperature (31.5 degrees C), all of these HXXNPF motif-containing molecules were capable of inhibiting syncytium formation. These results suggest that these HXXNPF motif-containing molecules mainly bind to the gp41 core and stop the fusion process mediated by the fusion-active core, resulting in inhibition of HIV-1 fusion and entry. The HXXNPF motif-containing molecules may be used as probes for studying the role of the HIV-1 gp41 core in the late stage of the membrane-fusion process.


Assuntos
Motivos de Aminoácidos , Células Gigantes/fisiologia , Proteína gp41 do Envelope de HIV/fisiologia , HIV-1/metabolismo , Fusão de Membrana/efeitos dos fármacos , Células 3T3 , Sequência de Aminoácidos , Animais , Células CHO , Proteínas do Capsídeo , Cricetinae , Cricetulus , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Células Gigantes/efeitos dos fármacos , Camundongos , Dados de Sequência Molecular , Proteínas Virais de Fusão/genética , Proteínas Virais de Fusão/metabolismo
17.
Protein Cell ; 9(12): 1004-1012, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-29497990

RESUMO

FcγRIIB, the only inhibitory IgG Fc receptor, functions to suppress the hyper-activation of immune cells. Numerous studies have illustrated its inhibitory function through the ITIM motif in the cytoplasmic tail of FcγRIIB. However, later studies revealed that in addition to the ITIM, the transmembrane (TM) domain of FcγRIIB is also indispensable for its inhibitory function. Indeed, recent epidemiological studies revealed that a non-synonymous single nucleotide polymorphism (rs1050501) within the TM domain of FcγRIIB, responsible for the I232T substitution, is associated with the susceptibility to systemic lupus erythematosus (SLE). In this review, we will summarize these epidemiological and functional studies of FcγRIIB-I232T in the past few years, and will further discuss the mechanisms accounting for the functional loss of FcγRIIB-I232T. Our review will help the reader gain a deeper understanding of the importance of the TM domain in mediating the inhibitory function of FcγRIIB and may provide insights to a new therapeutic target for the associated diseases.


Assuntos
Doenças Autoimunes/tratamento farmacológico , Doenças Autoimunes/imunologia , Receptores de IgG/química , Receptores de IgG/imunologia , Doenças Autoimunes/genética , Humanos , Domínios Proteicos
18.
Oncol Lett ; 16(3): 3193-3200, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30127914

RESUMO

Allergic rhinitis (AR) is the most common cause of inflammation of the nasal mucosa. It is also the most common form of non-infectious rhinitis associated with an immunoglobulin E (IgE)-mediated immune response against allergens. Previous studies have indicated that interleukin-1ß (IL-1ß) has a pathological role in the development of allergic asthma. The present study was designed to assess whether IL-1ß participates in the pathogenesis of AR. A total of 45 patients with AR were enrolled in the present study and were identified to have increased IL-1ß expression expressed by peripheral blood mononuclear cells (PBMCs), and the mitochondrial reactive oxygen species (ROS) and NLRP3 are required for IL-1ß synthesis in monocytes/macrophages and PBMCs from patients with AR. The levels of IL-1ß and interleukin-17 (IL-17) were increased in patients with AR and were positively correlated with each other. The results of the present study suggested that patients with AR have raised mitochondrial ROS levels, which may upregulate the expression of IL-1ß, affecting IL-17-production and serving a role in the pathogenesis of AR.

19.
PLoS One ; 13(1): e0191127, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29304137

RESUMO

[This corrects the article DOI: 10.1371/journal.pone.0167392.].

20.
J Exp Med ; 215(2): 521-535, 2018 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-29282251

RESUMO

Immune responses and neuroinflammation are critically involved in spinal cord injury (SCI). γδ T cells, a small subset of T cells, regulate the inflammation process in many diseases, yet their function in SCI is still poorly understood. In this paper, we demonstrate that mice deficient in γδ T cells (TCRδ-/- ) showed improved functional recovery after SCI. γδ T cells are detected at the lesion sites within 24 hours after injury and are predominantly of the Vγ4 subtype and express the inflammatory cytokine IFN-γ. Inactivating IFN-γ signaling in macrophages results in a significantly reduced production of proinflammatory cytokines in the cerebrospinal fluid (CSF) of mice with SCIs and improves functional recovery. Furthermore, treatment of SCI with anti-Vγ4 antibodies has a beneficial effect, similar to that obtained with anti-TNF-α. In SCI patients, γδ T cells are detected in the CSF, and most of them are IFN-γ positive. In conclusion, manipulation of γδ T cell functions may be a potential approach for future SCI treatment.


Assuntos
Interferon gama/biossíntese , Traumatismos da Medula Espinal/imunologia , Subpopulações de Linfócitos T/imunologia , Adulto , Animais , Modelos Animais de Doenças , Feminino , Genes Codificadores da Cadeia delta de Receptores de Linfócitos T , Humanos , Interferon gama/antagonistas & inibidores , Interferon gama/líquido cefalorraquidiano , Depleção Linfocítica , Macrófagos/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pessoa de Meia-Idade , Receptores de Antígenos de Linfócitos T gama-delta/deficiência , Receptores de Antígenos de Linfócitos T gama-delta/genética , Receptores de Antígenos de Linfócitos T gama-delta/metabolismo , Transdução de Sinais , Traumatismos da Medula Espinal/etiologia , Traumatismos da Medula Espinal/fisiopatologia , Adulto Jovem
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