Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 28
Filtrar
Mais filtros











Base de dados
Intervalo de ano de publicação
1.
Photodiagnosis Photodyn Ther ; 46: 104099, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38663487

RESUMO

BACKGROUND: To provide a new non-invasive method for the differentiation of diabetic nephropathy (DN) from non-diabetic renal disease (NDRD) by assessing retinal microstructure using optical coherence tomography angiography (OCTA). METHODS: OCTA parameters were recorded and their relationship with DN was analysed. A differential diagnosis regression model for DN was established, and the diagnostic efficiency was evaluated. RESULTS: Based on the pathological results of renal biopsy, 31 DN patients and 35 NDRD patients were included. Multivariate logistic regression analysis showed that DN was independently associated with the following parameters: 15.3 mm-1 ≤ vessel density (VD) full < 17.369 mm-1 (odds ratio [OR]=8.523; 95% confidence interval [CI]=1.387-52.352; P = 0.021), VD full < 15.3 mm-1 (OR=8.202; 95% CI=1.110-60.623; P = 0.039), DM duration > 60 months (OR=7.588; 95% CI=1.569-36.692; P = 0.012), and estimated glomerular filtration rate < 60 mL/min/1.73 m2 (OR=24.484; 95% CI=4.308-139.142; P < 0.001). The area under the receiver operating characteristic curve was 0.911, indicating a high diagnostic efficiency. CONCLUSIONS: VD full < 17.369 mm-1, DM duration > 60 months, and eGFR < 60 mL/min/1.73 m2 may indicate the presence of DN. OCTA may be an effective non-invasive method for identifying DN and NDRD.

2.
Sci Rep ; 13(1): 16552, 2023 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-37783777

RESUMO

Basal cell carcinoma (BCC) is the most common cancer with a rising incidence among white-skinned individuals. A number of epidemiological studies have suggested that obesity and serum 25-hydroxy-vitamin D (25(OH)D) levels may affect the arising of BCC. To address this, we selected 443 and 96 single nucleotide polymorphisms (SNPs) associated with body mass index (BMI) and serum level of 25(OH)D from large-scale genome-wide association studies (GWAS), respectively. The univariable and multivariable two-sample Mendelian randomization (MR) analyses were conducted with a series of sensitivity analyses to ensure the results were reliable and reproducible. The results of univariable two-sample MR analysis showed that higher BMI was related to lower risk for BCC (Odds ratio(OR) = 0.90; 95% confidence interval (CI),[0.81,0.99]; p = 0.02). In addition, this causal effect of BMI on BCC still remained (OR = 0.88; 95%CI,[- 0.22, - 0.03], p-value = 0.008) after adjusting for 25(OH)D level in the multivariable MR analysis. However, the results suggested that 25(OH)D level was not associated with BCC(OR = 1.02; 95%CI, [0.94,1.09], p-value = 0.67). In conclusion, similar to the conclusions of retrospective observational studies, the MR results indicate that high BMI is an independent protective factor for BCC. Meanwhile, vitamin D levels may not be causally associated with the risk of basal cell carcinoma and increasing vitamin D supplementation is unlikely to reduce the risk.


Assuntos
Carcinoma Basocelular , Estudo de Associação Genômica Ampla , Humanos , Índice de Massa Corporal , Análise da Randomização Mendeliana/métodos , Estudos Retrospectivos , Vitamina D , Calcifediol , Carcinoma Basocelular/epidemiologia , Carcinoma Basocelular/genética , Polimorfismo de Nucleotídeo Único
4.
iScience ; 26(5): 106639, 2023 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-37192967

RESUMO

Dual or multi-targets therapy targeting epidermal growth factor receptor variant III (EGFRvIII) and other molecular may relax the constraint for glioblastoma (GBM), putting forward the urgent requirement of finding candidate molecules. Here, the insulin-like growth factor binding protein-3 (IGFBP3) was considered a candidate, whereas the mechanisms of IGFBP3 production remain unclear. We treated GBM cells with exogenous transforming growth factor ß (TGF-ß) to simulate the microenvironment. We found that TGF-ß and EGFRvIII transactivation induced the activation of transcription factor c-Jun, which specifically bound to the promoter region of IGFBP3 through Smad2/3 and ERK1/2 pathways and promoted the production and secretion of IGFBP3. IGFBP3 knockdown inhibited the activation of TGF-ß and EGFRvIII signals and the malignant behaviors triggered by them in vitro and in vivo. Collectively, our results indicated a positive feedback loop of p-EGFRvIII/IGFBP3 under administration of TGF-ß, blocking IGFBP3 may be an additional target in EGFRvIII-expressing GBM-selective therapeutic strategy.

5.
J Nutr ; 153(7): 1930-1943, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37182694

RESUMO

BACKGROUND: The glucose requirement of dairy cows is mainly met by increasing the rate of hepatic gluconeogenesis. However, due to negative energy balance, the liver of periparturient cows is under oxidative stress induced by lipid over-mobilization, and hepatic gluconeogenesis is reduced. Studies have demonstrated that resveratrol, which is widely known for its antioxidant properties, can alter hepatic gluconeogenesis. However, it is not clear whether resveratrol could regulate hepatic gluconeogenesis by its antioxidant properties. OBJECTIVES: This study aims to investigate the precise effect of resveratrol in hepatic gluconeogenesis, the role of resveratrol on hydrogen peroxide (H2O2)-induced oxidative stress in hepatocytes and the potential mechanism using primary hepatocytes. METHODS: Primary hepatocytes were isolated from 5 healthy Holstein calves (1 d old, 30 to 40 kg, fasted) and treated with different concentrations of resveratrol (0, 5, 10, 25, or 50 µM) combined with or without H2O2 (0, 100, or 200 µM) induction for 12 h. RESULTS: Resveratrol enhanced the expression of gluconeogenic genes of calf hepatocytes in a dose-dependent manner (P < 0.05). Conversely, H2O2 suppressed the expression of gluconeogenic genes and induced oxidative stress (P < 0.05), which was improved by resveratrol in calf hepatocytes (P < 0.001). Furthermore, the mechanistic target of rapamycin complex 2 (mTORC2)-AKT pathway was found to negatively regulate gluconeogenesis. An AKT inhibitor was used to assess the role of the mTORC2-AKT pathway in the effects of resveratrol. The results showed resveratrol promoted hepatic gluconeogenesis by inhibiting the mTORC2-AKT pathway. Moreover, sestrin 2 (SESN2) upregulated the activity of mTORC2. We further found that resveratrol decreased SESN2 levels (P < 0.001). CONCLUSIONS: This study indicated that resveratrol enhances the gluconeogenic capacity of calf hepatocytes by improving H2O2-induced oxidative stress and modulating the activity of the SESN2-mTORC2-AKT pathway, implying that resveratrol may be a promising target for ameliorating liver oxidative stress in transition cows.


Assuntos
Gluconeogênese , Proteínas Proto-Oncogênicas c-akt , Feminino , Animais , Bovinos , Resveratrol/farmacologia , Resveratrol/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Peróxido de Hidrogênio , Hepatócitos , Fígado/metabolismo , Alvo Mecanístico do Complexo 2 de Rapamicina/metabolismo
6.
Cell Death Dis ; 14(4): 292, 2023 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-37185889

RESUMO

Evidence shows that short-chain fatty acids (SCFAs) play an important role in health maintenance and disease development. In particular, butyrate is known to induce apoptosis and autophagy. However, it remains largely unclear whether butyrate can regulate cell ferroptosis, and the mechanism by which has not been studied. In this study, we found that RAS-selective lethal compound 3 (RSL3)- and erastin-induced cell ferroptosis were enhanced by sodium butyrate (NaB). With regard to the underlying mechanism, our results showed that NaB promoted ferroptosis by inducing lipid ROS production via downregulating the expression of solute carrier family 7 member 11 (SLC7A11) and glutathione peroxidase 4 (GPX4). Moreover, the FFAR2-AKT-NRF2 axis and FFAR2-mTORC1 axis accounts for the NaB-mediated downregulation of SLC7A11 and GPX4, respectively, in a cAMP-PKA-dependent manner. Functionally, we found that NaB can inhibit tumor growth and the inhibitory effect could be eliminated by administrating MHY1485 (mTORC1 activator) and Ferr-1 (ferroptosis inhibitor). Altogether, in vivo results suggest that NaB treatment is correlated to the mTOR-dependent ferroptosis and consequent tumor growth through xenografts and colitis-associated colorectal tumorigenesis, implicating the potential clinical applications of NaB for future colorectal cancer treatments. Based on all these findings, we have proposed a regulatory mechanism via which butyrate inhibits the mTOR pathway to control ferroptosis and consequent tumorigenesis.


Assuntos
Ferroptose , Humanos , Ácido Butírico/farmacologia , Carcinogênese , Transformação Celular Neoplásica , Alvo Mecanístico do Complexo 1 de Rapamicina , Serina-Treonina Quinases TOR
7.
Adv Sci (Weinh) ; 10(17): e2206826, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37083230

RESUMO

The amino acid-stimulated Rag GTPase pathway is one of the main pathways that regulate mechanistic target of rapamycin complex 1 (mTORC1) activation and function, but little is known about the effects of growth factors on Rag GTPase-mediated mTORC1 activation. Here, a highly conserved insulin-responsive phosphorylation site on folliculin (FLCN), Ser62, that is phosphorylates by AKT1 is identified and characterized. mTORC2-AKT1 is localized on lysosomes, and RagD-specific recruitment of mTORC2-AKT1 on lysosomes is identified as an essential step in insulin-AKT1-mediated FLCN phosphorylation. Additionally, FLCN phosphorylation inhibits the activity of RagC GTPase and is essential for insulin-induced mTORC1 activation. Functionally, phosphorylated FLCN promotes cell viability and induces autophagy, and also regulates in vivo tumor growth in an mTORC1-dependent manner. Its expression is also positively correlated with mTORC1 activity in colon cancer, clear cell renal cell carcinoma, and chordoma. These results indicate that FLCN is an important intermediate for cross-talk between the amino acid and growth factor pathways. Further, FLCN phosphorylation may be a promising therapeutic target for diseases characterized by mTORC1 dysregulation.


Assuntos
Insulina , Transdução de Sinais , Humanos , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Fosforilação , Transdução de Sinais/fisiologia , Insulina/metabolismo , Aminoácidos/metabolismo , Carcinogênese , Alvo Mecanístico do Complexo 2 de Rapamicina/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Supressoras de Tumor/metabolismo
8.
PeerJ ; 11: e14902, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36919167

RESUMO

With economic and social globalization, invasive alien species have significantly threatened local ecological security. Identifying the invasive mechanisms of invasive alien species can aid in preventing species invasions and protecting local ecological and economic security. As a globally invasive plant, Ageratina adenophora (Asteraceae) has spread to many parts of the world and had a seriously impacted the ecology and economy of its invaded areas. Using observational data and Landsat OLI images in an arid valley region in southwest China, this study examined how climate, human activity and environmental factors influence the invasion of A. adenophora and its underlying mechanism. Our results showed that the invasion abundance of A. adenophora was significantly affected by environmental factors (the relative importance was 87.2%), but was less influenced by human activity and climate factors (the relative importance was 2% and 10.8%, respectively). The A. adenophora abundance significantly decreased with aspect, community canopy density, shrub layer coverage, herb layer coverage, Simpson diversity index of shrub and herb layers, the shortest distance to residential areas and temperature seasonality, whereas it increased with soil moisture, temperature annual range, precipitation of wettest month and precipitation of driest month. We conclude that biotic competition is the most influential factor in the invasion of this plant in the arid valley regions. Our results are of great significance for invasion prevention and forest conservation and management in southwest China. Our work emphasized that optimizing the community structure, such as by increasing canopy and shrub coverage and species biodiversity, may help control and mitigate the A. adenophora invasion in southwest China.


Assuntos
Ageratina , Meio Ambiente , Atividades Humanas , China , Biodiversidade , Ecologia , Agricultura Florestal , Biota
9.
PLoS Genet ; 19(2): e1010629, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36787291

RESUMO

Pharmacological vitamin C (VC) is a potential natural compound for cancer treatment. However, the mechanism underlying its antitumor effects remains unclear. In this study, we found that pharmacological VC significantly inhibits the mTOR (including mTORC1 and mTORC2) pathway activation and promotes GSK3-FBXW7-mediated Rictor ubiquitination and degradation by increasing the cellular ROS. Moreover, we identified that HMOX1 is a checkpoint for pharmacological-VC-mediated mTOR inactivation, and the deletion of FBXW7 or HMOX1 suppresses the regulation of pharmacological VC on mTOR activation, cell size, cell viability, and autophagy. More importantly, it was observed that the inhibition of mTOR by pharmacological VC supplementation in vivo produces positive therapeutic responses in tumor growth, while HMOX1 deficiency rescues the inhibitory effect of pharmacological VC on tumor growth. These results demonstrate that VC influences cellular activities and tumor growth by inhibiting the mTOR pathway through Rictor and HMOX1, which may have therapeutic potential for cancer treatment.


Assuntos
Ácido Ascórbico , Neoplasias , Humanos , Proteína 7 com Repetições F-Box-WD/metabolismo , Ácido Ascórbico/farmacologia , Quinase 3 da Glicogênio Sintase/metabolismo , Proteína Companheira de mTOR Insensível à Rapamicina/genética , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Alvo Mecanístico do Complexo 2 de Rapamicina/genética , Alvo Mecanístico do Complexo 2 de Rapamicina/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/genética , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Fatores de Transcrição/metabolismo , Heme Oxigenase-1/genética , Heme Oxigenase-1/metabolismo
10.
Microbes Infect ; 25(5): 105099, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36642296

RESUMO

Enterotoxigenic Escherichia coli (ETEC) is the main causative pathogen of diarrhea. It causes acute watery diarrhea that leads to rapid dehydration and prostration within hours. ETEC is still an important cause of neonatal and post-weaning diarrhea in pigs. However, the mechanism underlying ETEC-induced diarrhea is not yet clear. In this study, we investigated these mechanisms and found that the mTORC1 pathway plays a role in the host response to ETEC F4 infection. Specifically, we found that ETEC F4 treatment significantly repressed mTORC1 activity as well as cell proliferation, promoted apoptosis and regulated the expression of diarrhea-related genes via the promotion of PKA-mediated phosphorylation of SIN1, which plays a critical role in the assembly of mTORC2. These findings indicate that PKA is a checkpoint for ETEC-induced diarrhea. In terms of potential therapeutic strategies, we found that ZnSO4 dramatically rescued ETEC F4-induced the inhibition of mTORC1 activity and cell viability and the induction of apoptosis and alterations in the expression of diarrhea-related genes. Thus, the present findings demonstrate that ETEC F4 influences mTORC1 activation by inhibiting the assembly of mTORC2 through PKA-mediated phosphorylation of SIN1. Further, supplementation with ZnSO4 is an effective strategy for blocking the effect of ETEC F4 on mTORC1 activation, and it may have potential clinical applications in the treatment of ETEC F4-induced diarrhea.


Assuntos
Escherichia coli Enterotoxigênica , Infecções por Escherichia coli , Suínos , Animais , Diarreia , Apoptose , Células Epiteliais
11.
Int Immunopharmacol ; 116: 109739, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36706590

RESUMO

Dendritic cells (DCs) play pivotal roles in immune responses. The differentiation and function of DCs are regulated by environmental metabolites. Putrescine is ubiquitous in various metabolic microenvironments and its immunoregulation has been of increasing interest. However, the mechanisms associated with its DC-induced immunoregulation remain unclear. In this study, we found putrescine promoted induction of immature bone marrow derived DCs (BMDCs), along with the increased phagocytosis and migration, and altered cytokine secretion in immature BMDCs. Transcriptomic profiles indicated significantly impaired inflammatory-related pathways, elevated oxidative phosphorylation, and decreased p-STAT3 (Tyr705) expression. Additionally, putrescine performed minor influence on the lipopolysaccharide (LPS)-induced maturation of BMDCs but significantly impaired LPS-induced DC-elicited allogeneic T-cell proliferation as well as the cytokine secretion. Furthermore, molecular docking and dynamics on the conjugation between putrescine and STAT3 revealed that putrescine could be stably bound to the hydrophilic cavity in STAT3 and performed significant influence on the Tyr705 phosphorylation. CUT&Tag analysis uncovered altered motifs, downregulated IFN-γ response, and upregulated p53 pathway in Putrescine group compared with Control group. In summary, our results demonstrated for the first time that putrescine might accelerate the differentiation of BMDCs by inhibiting the phosphorylation of STAT3 at Tyr705. Given that both DCs and putrescine have ubiquitous and distinct roles in various immune responses and pathogeneses, our findings may provide more insights into polyamine immunoregulation on DCs, as well as distinct strategies in the clinical utilization of DCs by targeting polyamines.


Assuntos
Lipopolissacarídeos , Putrescina , Fosforilação , Putrescina/farmacologia , Putrescina/metabolismo , Lipopolissacarídeos/metabolismo , Medula Óssea , Simulação de Acoplamento Molecular , Diferenciação Celular , Células Cultivadas , Citocinas/metabolismo , Células Dendríticas , Células da Medula Óssea/metabolismo
12.
Cell Prolif ; 56(3): e13360, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36377675

RESUMO

Paeonia is a well-known species of ornamental plants, traditional Chinese medicines, and emerging oilseed crops. Apart from nutritional unsaturated fatty acids, the seeds of peonies are rich in stilbenes characterized by their wide-ranging health-promoting properties. Although the typical stilbene resveratrol has been widely reported for its multiple bioactivities, it remains uncertain whether the trimer of resveratrol trans-gnetin H has properties that regulate cancer cell viability, let alone the underlying mechanism. Autophagy regulated by trans-gnetin H was detected by western blotting, immunofluorescence, and quantitative real-time PCR. The effects of trans-gnetin H on apoptosis and proliferation were examined by flow cytometry, colony formation and Cell Counting Kit-8 assays. Trans-gnetin H significantly inhibits cancer cell viability through autophagy by suppressing the phosphorylation of TFEB and promoting its nuclear transport. Mechanistically, trans-gnetin H inhibits the activation and lysosome translocation of mTORC1 by inhibiting the activation of AMPK, indicating that AMPK is a checkpoint for mTORC1 inactivation induced by trans-gnetin H. Moreover, the binding of TSC2 to Rheb was markedly increased in response to trans-gnetin H stimulation. Similarly, trans-gnetin H inhibited the interaction between Raptor and RagC in an AMPK-dependent manner. More importantly, trans-gnetin H-mediated autophagy highly depends on the AMPK-mTORC1 axis. We propose a regulatory mechanism by which trans-gnetin H inhibits the activation of the mTORC1 pathway to control cell autophagy.


Assuntos
Neoplasias , Paeonia , Estilbenos , Humanos , Proteínas Quinases Ativadas por AMP , Autofagia , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Paeonia/química , Paeonia/metabolismo , Resveratrol , Sementes/química , Sementes/metabolismo , Estilbenos/análise , Estilbenos/química , Estilbenos/farmacologia
13.
Nutrients ; 14(23)2022 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-36501031

RESUMO

Paeonia species are well-known ornamental plants that are used in traditional Chinese medicines. The seeds of these species are rich in stilbenes, which have wide-ranging health-promoting effects. In particular, resveratrol, which is a common stilbene, is widely known for its anticancer properties. Suffruticosol C, which is a trimer of resveratrol, is the most dominant stilbene found in peony seeds. However, it is not clear whether suffruticosol C has cancer regulating properties. Therefore, in the present study, we aimed to determine the effect of suffruticosol C against various cancer cell lines. Our findings showed that suffruticosol C induces autophagy and cell cycle arrest instead of cell apoptosis and ferroptosis. Mechanistically, suffruticosol C regulates autophagy and cell cycle via inhibiting the mechanistic target of rapamycin complex 1 (mTORC1) signaling. Thus, our findings imply that suffruticosol C regulates cancer cell viability by inducing autophagy and cell cycle arrest via the inhibition of mTORC1 signaling.


Assuntos
Paeonia , Estilbenos , Alvo Mecanístico do Complexo 1 de Rapamicina , Autofagia , Estilbenos/farmacologia , Resveratrol/farmacologia , Pontos de Checagem do Ciclo Celular , Apoptose
14.
Mol Nutr Food Res ; 66(23): e2200186, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36189894

RESUMO

SCOPE: Mechanistic target of rapamycin (mTOR) serves as a central signaling node in the coordination of cell growth and metabolism, and it functions via two distinct complexes, namely, mTOR complex 1 (mTORC1) and mTORC2. mTORC1 plays a crucial role in sensing amino acids, whereas mTORC2 involves in sensing growth factors. However, it remains largely unclear whether mTORC2 can sense amino acids and the mechanism by which amino acids regulate mTORC2 has not been studied. METHODS AND RESULTS: After treating cells with indicated concentration of amino acids for different time, it is found that the mTORC2 activation is significantly increased in response to amino acids stimulation, especially cystine. Particularly, knockdown solute carrier family 7 member 11 (SLC7A11) by siRNA shows that SLC7A11-mediated cystine uptake is responsible for activating mTORC2. Mechanistically, the study finds that p38 is activated in response to cystine stimulation, and co-immunoprecipitation (Co-IP) experiments suggest that p38 regulates the assembly of components within mTORC2 by mediating the phosphorylation of the mTORC2 subunit mitogen-activated protein kinase-interacting protein 1 (Sin1) in a cystine-dependent manner. Finally, combined with inducers and inhibitors of ferroptosis and cell viability assay, the study observes that cystine-mediated regulation of the p38-Sin1-mTOR-AKT pathway induces resistance to ferroptosis. CONCLUSION: These results indicate that cystine-induced activation of the p38-Sin1-mTORC2-AKT pathway suppresses ferroptosis.


Assuntos
Ferroptose , Neoplasias , Alvo Mecanístico do Complexo 2 de Rapamicina/metabolismo , Fosforilação , Cistina/farmacologia , Cistina/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Complexos Multiproteicos/química , Complexos Multiproteicos/genética , Complexos Multiproteicos/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Serina-Treonina Quinases TOR/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo
15.
Adv Nutr ; 13(5): 1882-1900, 2022 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-35561748

RESUMO

Mechanistic target of rapamycin complex 1 (mTORC1) is a multi-protein complex widely found in eukaryotes. It serves as a central signaling node to coordinate cell growth and metabolism by sensing diverse extracellular and intracellular inputs, including amino acid-, growth factor-, glucose-, and nucleotide-related signals. It is well documented that mTORC1 is recruited to the lysosomal surface, where it is activated and, accordingly, modulates downstream effectors involved in regulating protein, lipid, and glucose metabolism. mTORC1 is thus the central node for coordinating the storage and mobilization of nutrients and energy across various tissues. However, emerging evidence indicated that the overactivation of mTORC1 induced by nutritional disorders leads to the occurrence of a variety of metabolic diseases, including obesity and type 2 diabetes, as well as cancer, neurodegenerative disorders, and aging. That the mTORC1 pathway plays a crucial role in regulating the occurrence of metabolic diseases renders it a prime target for the development of effective therapeutic strategies. Here, we focus on recent advances in our understanding of the regulatory mechanisms underlying how mTORC1 integrates metabolic inputs as well as the role of mTORC1 in the regulation of nutritional and metabolic diseases.


Assuntos
Diabetes Mellitus Tipo 2 , Doenças Metabólicas , Aminoácidos/metabolismo , Glucose/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intercelular , Lipídeos , Alvo Mecanístico do Complexo 1 de Rapamicina , Doenças Metabólicas/metabolismo , Nucleotídeos , Nutrientes , Serina-Treonina Quinases TOR/metabolismo
16.
J Agric Food Chem ; 69(51): 15716-15727, 2021 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-34918923

RESUMO

T-2 toxin is a trichothecene mycotoxin commonly found in animal feed and agricultural products. Evidence indicates that T-2 toxin induces apoptosis and autophagy. This study investigated the role of ferroptosis in T-2 toxin cytotoxicity. RAS-selective lethal compound 3 (RSL3) and Erastin were applied to initiate ferroptosis. RSL3- and Erastin-initiated cell death were enhanced by T-2 toxin. Treatment with the ferroptosis inhibitor ferrostatin-1 markedly restored the sensitizing effect of T-2 toxin to RSL3- or Erastin-initiated apoptosis, suggesting that ferroptosis plays a vital role in T-2 toxin-induced cytotoxicity. Mechanistically, T-2 toxin promoted ferroptosis by inducing lipid reactive oxygen species (ROS), as N-acetyl-l-cysteine significantly blocked T-2 toxin-induced ferroptosis. Moreover, T-2 toxin decreased the expression of solute carrier family 7 member 11 (SLC7A11) and failed to further enhance ferroptosis in SLC7A11-deficient cells. SLC7A11 overexpression significantly rescued the enhanced ferroptosis caused by T-2 toxin. T-2 toxin induces ferroptosis by downregulating SLC7A11 expression. Ferroptosis mediates T-2 toxin-induced cytotoxicity by increasing ROS and downregulating SLC7A11 expression.


Assuntos
Ferroptose , Toxina T-2 , Animais , Apoptose , Lipídeos , Espécies Reativas de Oxigênio , Toxina T-2/toxicidade
17.
Reprod Fertil Dev ; 33(5): 363-371, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33641714

RESUMO

MicroRNAs (miRNAs) have been determined to participate in the process of oestradiol production. Generally, there are two pathways by which oestradiol levels change, one being the state of cells (i.e. the status of enzymes involved in the synthesis of hormones such as oestradiol) and the other being the number of cells that secrete oestradiol. It is known that oestrogens are the main steroids produced by granulosa cells (GCs) of mature ovarian follicles. In this study we explored the function of miR-18b in rabbit GCs by overexpressing or inhibiting its activity. We found that miR-18b silencing promoted the secretion of oestradiol by significantly affecting the expression of steroidogenesis-related genes. Thus, miR-18b may act as a negative regulator of the production of enzymes related to oestradiol synthesis and affect oestradiol production. Furthermore, the effects of miR-18b on the proliferation, cell cycle and apoptosis of GCs were investigated using a cell counting kit (CCK-8) proliferation assay, detection of annexin V-fluorescein isothiocyanate apoptosis, flow cytometry and quantitative polymerase chain reaction. The results showed that miR-18b upregulated GC apoptosis (miR-18b overexpression decreases cell growth and stimulates apoptosis). These findings suggest that miR-18b and the oestrogen receptor 1 (ESR1) gene may be attractive targets to further explore the molecular regulation of GCs. The miR-18b may also explain, in part, the abnormal folliculogenesis in mammals caused by conditions such as polycystic ovary syndrome, primary ovarian insufficiency, and others.


Assuntos
Células da Granulosa/fisiologia , MicroRNAs/fisiologia , Animais , Apoptose , Ciclo Celular , Proliferação de Células , Células Cultivadas , Epigênese Genética/genética , Estradiol/biossíntese , Estradiol/genética , Receptor alfa de Estrogênio/genética , Feminino , Expressão Gênica , Inativação Gênica , MicroRNAs/genética , Coelhos , Transfecção
18.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 32(2): 191-5, 2016 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-26927379

RESUMO

OBJECTIVE: To compare the differentiation, inducing effects of human placenta mesenchymal stem cells (hPMSCs) on IL-10(+) T cells derived from cord blood and peripheral blood, and investigate the effect of IFN-γ on the induction. METHODS: The hPMSCs were isolated from human placenta and cultured. The expression of programmed death ligand 1 (PD-L1) in hPMSCs was detected by reverse transcriptase PCR and flow cytometry (FCM), respectively. Mononuclear cells were isolated from cord blood and peripheral blood of healthy donors by Ficoll density gradient centrifugation, and T cells were purified by sheep red blood cells. Then hPMSCs, pretreated with PD-L1 mAb or IFN-γ, were co-cultured with phytohaemagglutinin (PHA)-activated T cells. Percentages of CD4(+)IL-10(+) and CD8(+)IL-10(+) T cells in cord blood and peripheral blood T cells were analyzed by FCM. RESULTS: hPMSCs could induce the differentiation of CD4(+)IL-10(+) and CD8(+)IL-10(+) T cells from cord blood or peripheral blood T cells, and the number of IL-10(+) T cells in the peripheral blood T cells was significantly higher than that in the cord blood T cells. Pretreatment with IFN-γ markedly enhanced the differentiation, inducing ability of hPMSCs. PD-L1 was highly expressed in hPMSCs, and the expression was also significantly promoted by IFN-γ. After the expression of PD-L1 was blocked in hPMSCs, the percentages of CD4(+)IL-10(+) and CD8(+)IL-10(+) T cells obviously decreased in cord blood and peripheral blood T cells. CONCLUSION: The ability of hPMSCs to induce the differentiation of IL-10(+) T cells from peripheral blood T cells was apparently stronger than that in cord blood T cells. IFN-γ could up-regulate the number of IL-10(+)T cells differentiated from cord blood and peripheral blood T cells in the present of hPMSCs by enhancing the expression of PD-L1 in hPMSCs.


Assuntos
Antígeno B7-H1/metabolismo , Diferenciação Celular/efeitos dos fármacos , Interferon gama/farmacologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Linfócitos T/efeitos dos fármacos , Adulto , Animais , Antígeno B7-H1/genética , Células Cultivadas , Técnicas de Cocultura , Feminino , Sangue Fetal/citologia , Citometria de Fluxo , Expressão Gênica/efeitos dos fármacos , Humanos , Interleucina-10/metabolismo , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Placenta/citologia , Gravidez , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Ovinos , Linfócitos T/citologia , Linfócitos T/metabolismo
19.
Cytotherapy ; 17(11): 1560-71, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26432559

RESUMO

BACKGROUND AIMS: Mesenchymal stromal cells (MSCs) and regulatory T cells (Treg) have been successfully used in treating autoimmune diseases accompanied by abundant inflammatory cytokines such as interferon (IFN)-γ and tumor necrosis factor (TNF)-α. Therefore, this work investigated the effects of IFN-γ and TNF-α on the ability of human placenta-derived mesenchymal stromal cells (hPMSCs) on inducing the differentiation of CD4(+)interleukin (IL)-10(+)and CD8(+)IL-10(+)Treg subsets. METHODS: Human PMSCs were co-cultured with T cells in the presence or absence of a trans-well system or anti- programmed death ligand-2 (PDL2) monoclonal antibody (mAb), respectively. CD4(+)IL-10(+)and CD8(+)IL-10(+)Treg subsets, as well as the levels of IL-10 in the supernatants, were detected on this basis. Examinations were conducted to explore the impact of IFN-γ and TNF-α on the expression of PDL2 in hPMSCs. In this process, flow cytometry, Western blot and reverse-transcriptase-polymerase chain reaction were used. RESULTS: CD4(+)IL-10(+)and CD8(+)IL-10(+)Treg subsets from T cells either non-activated or activated by use of phytohaemagglutinin (PHA) or CD3/CD28mAb significantly increased in the presence of hPMSCs. However, these levels markedly decreased after blocking the expression of PDL2 in hPMSCs. IL-10 followed the same pattern. Furthermore, the percentages of CD4(+)IL-10(+) and CD8(+)IL-10(+)T cells also sharply declined under the trans-well system, whereas the percentages as well as the expression of PDL2 in hPMSCs oppositely raised after hPMSCs pre-stimulated by IFN-γ and TNF-α. IFN-γ could promote the expression of PDL2 partly through the JAK/STAT signaling pathway. CONCLUSIONS: IFN-γ and TNF-α could promote the ability of hPMSCs in inducing the differentiation of CD4(+)IL-10(+)and CD8(+)IL-10(+)Treg subsets and enhance the expression of PDL2 in hPMSCs. These would benefit the application of hPMSCs in clinical trials.


Assuntos
Interferon gama/metabolismo , Interleucina-10/metabolismo , Células-Tronco Mesenquimais/fisiologia , Placenta/citologia , Proteína 2 Ligante de Morte Celular Programada 1/metabolismo , Linfócitos T Reguladores/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/metabolismo , Antígenos CD8/metabolismo , Diferenciação Celular/efeitos dos fármacos , Técnicas de Cocultura , Feminino , Humanos , Interferon gama/imunologia , Interferon gama/farmacologia , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Gravidez , Linfócitos T Reguladores/efeitos dos fármacos , Linfócitos T Reguladores/imunologia , Fator de Necrose Tumoral alfa/farmacologia
20.
Cancer Invest ; 32(6): 262-71, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24787022

RESUMO

B7-H3 has been detected in different cancers and correlated to tumor progression and outcome in cancer patients. In this study, we investigated the expression of B7-H3 in tissues and cells of primary hepatocellular carcinoma (PHC) patients. The research showed that B7-H3 is aberrantly expressed in PHC tissues and cells, and its high expression on HepG2 cells significantly promotes cell proliferation, adhesion, migration, and invasion capacity; moreover, it inhibits the proliferation of CD8(+) T cells. Thus, B7-H3 may have a critical role in PHC and it may enhance tumor escape from the immune surveillance of CD8(+) T cells.


Assuntos
Antígenos B7/biossíntese , Carcinogênese , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , Antígenos B7/imunologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Carcinoma Hepatocelular/imunologia , Carcinoma Hepatocelular/patologia , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Células Hep G2 , Humanos , Neoplasias Hepáticas/imunologia , Neoplasias Hepáticas/patologia , Linfócitos do Interstício Tumoral/imunologia , Evasão Tumoral
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA