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1.
Int J Mol Sci ; 24(7)2023 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-37047287

RESUMO

Despite the well-studied effects of the full-length membrane-locating isoform Iso1 of Programmed Cell Death Protein-Ligand 1 (PD-L1) on immunosuppression, little is known about another membrane-locating isoform, Iso2. While expressional and survival analysis of liver cancer patients indicated that Iso2 plays a tumor-suppressive role, our results also indicated that the tumor-promoting and immune-suppressive effects of Iso1 depended on the positive expression of Iso2. Through mediation analysis, we discovered several downstream genes or pathways of Iso2 and investigated their effects on the Iso1-regulating survival. Among all potential downstream immune factors, Iso2 was inclined to activate the proliferation of T cells by regulating chemokine activity and increasing CD3 levels by promoting TNF expression. Similar results were confirmed in the Mongolian liver cancer cohort, and the Iso2/TNF/T-cell axis was verified in several other cancers in the TCGA cohort. Finally, we demonstrated the promoting effects of Iso2 in terms of producing TNF and increasing T cells both in vitro and in vivo. Our findings illustrate that PD-L1 Iso2 can increase the number of T cells in the tumor microenvironment by elevating TNF levels, which is a necessary part of the tumor-suppressive effects of Iso1 in liver cancer.


Assuntos
Antígeno B7-H1 , Neoplasias Hepáticas , Humanos , Antígeno B7-H1/genética , Antígeno B7-H1/metabolismo , Proliferação de Células/genética , Terapia de Imunossupressão , Ligantes , Neoplasias Hepáticas/genética , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Microambiente Tumoral/genética , Fatores de Necrose Tumoral/metabolismo
2.
Int J Mol Sci ; 24(17)2023 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-37686324

RESUMO

Chlorogenic acid (CGA) is a bioactive substance with anti-inflammatory activities. Clusters of CD36 have been suggested to be widely involved in inflammatory damage. However, the mechanism of CGA protecting against LPS-induced inflammation involving the CD36 regulation is unclear. Here, we demonstrated that CGA protected against LPS-induced cell death and decreased the production of ROS. Moreover, the SOD, CAT, and GSH-Px activities were also upregulated in CGA-treated cells during LPS stimulation. CGA reduced COX-2 and iNOS expression and IL-1ß, IL-6, and TNF-α secretion in LPS-stimulated RAW264.7 macrophages. In addition, CGA treatment widely involved in immune-related signaling pathways, including NF-κB signaling, NOD-like receptor signaling, and IL-17 signaling using transcriptomic analysis and CD36 also markedly reduced during CGA pretreatment in LPS-induced RAW264.7 cells. Furthermore, the CD36 inhibitor SSO attenuated inflammation and oxidative stress by enabling activation of the AMPK/PGC-1α cascade. These results indicate that CGA might provide benefits for the regulation of inflammatory diseases by modulating CD36/AMPK/PGC-1α to alleviate oxidative stress.


Assuntos
Proteínas Quinases Ativadas por AMP , Ácido Clorogênico , Humanos , Ácido Clorogênico/farmacologia , Lipopolissacarídeos/toxicidade , Macrófagos , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Estresse Oxidativo , Antígenos CD36
3.
Gut ; 70(11): 2159-2171, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-33303565

RESUMO

OBJECTIVE: Dysfunction of endoplasmic reticulum (ER) proteins is closely related to homeostasis disturbance and malignant transformation of hepatocellular carcinoma (HCC). Reticulons (RTN) are a family of ER-resident proteins critical for maintaining ER function. Nevertheless, the precise roles of RTN in HCC remain largely unclear. The aim of the study is to examine the effect of reticulon family member RTN3 on HCC development and explore the underlying mechanisms. DESIGN: Clinical HCC samples were collected to assess the relationship between RTN3 expression and patients' outcome. HCC cell lines were employed to examine the effects of RTN3 on cellular proliferation, apoptosis and signal transduction in vitro. Nude mice model was used to detect the role of RTN3 in modulating tumour growth in vivo. RESULTS: We found that RTN3 was highly expressed in normal hepatocytes but frequently downregulated in HCC. Low RTN3 expression predicted poor outcome in patients with HCC in TP53 gene mutation and HBV infection status-dependent manner. RTN3 restrained HCC growth and induced apoptosis by activating p53. Mechanism studies indicated that RTN3 facilitated p53 Ser392 phosphorylation via Chk2 and enhanced subsequent p53 nuclear localisation. RTN3 interacted with Chk2, recruited it to ER and promoted its activation in an ER calcium-dependent manner. Nevertheless, the tumour suppressive effects of RTN3 were abrogated in HBV-positive cells. HBV surface antigen competed with Chk2 for RTN3 binding and blocked RTN3-mediated Chk2/p53 activation. CONCLUSION: The findings suggest that RTN3 functions as a novel suppressor of HCC by activating Chk2/p53 pathway and provide more clues to better understand the oncogenic effects of HBV.


Assuntos
Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/virologia , Vírus da Hepatite B/patogenicidade , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/virologia , Proteína Supressora de Tumor p53/metabolismo , Animais , Apoptose , Carcinogênese/metabolismo , Proteínas de Transporte/metabolismo , Linhagem Celular Tumoral , Quinase do Ponto de Checagem 2/metabolismo , Retículo Endoplasmático/metabolismo , Hepatócitos/metabolismo , Humanos , Masculino , Proteínas de Membrana/metabolismo , Camundongos Endogâmicos BALB C , Camundongos Nus , Proteínas do Tecido Nervoso/metabolismo , Proteína Supressora de Tumor p53/genética
4.
Molecules ; 26(17)2021 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-34500612

RESUMO

Red cabbage (Brassica oleracea L. var. capitata) continues to receive increasing attention on its health-promoting properties because of its high glucosinolate content. Glucosinolates are an unstable active substance; however, there are few studies on their changes in different cooking processes. In this study, we investigated the effects of processing methods (boiling, steaming, microwave heating, frying, stir-frying) and boiling time on glucosinolates in red cabbage. Ten glucosinolates, including 4-methoxyglucobrassicin, neoglucobrassicin, glucoalyssin, glucobrassicin, glucoraphanin, glucoiberin, progoitrin, gluconapin and sinigrin, in red cabbage were detected. Decreases of 32.36%, 24.83%, 25.27%, 81.11% and 84.29% for total glucosinolates were observed after boiling, microwaving, steaming, frying and stir-frying. Indole glucosinolates were more efficiently lost compared to aliphatic glucosinolates after boiling, while microwaving, steaming, frying and stir-frying also resulted in a greater reduction in indole glucosinolates than aliphatic glucosinolates. Glucoalyssin, glucoerucin and sinigrin were more thermal sensitive than other glucosinolates. It was confirmed that microwaving and steaming retained higher levels of glucosinolates than other methods and may be better for cooking red cabbage.


Assuntos
Brassica/química , Glucosinolatos/química , Cromatografia Líquida/métodos , Culinária/métodos , Glucose/análogos & derivados , Glucose/química , Imidoésteres/química , Indóis/química , Micro-Ondas , Oximas/química , Sulfóxidos/química , Espectrometria de Massas em Tandem/métodos
5.
Biochem Biophys Res Commun ; 508(4): 1113-1119, 2019 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-30553444

RESUMO

Immune responses against antigens generally require an efficient activation of antigen-presenting cells (APCs). Currently, the targeting of vaccine antigens to APCs has emerged as a promising strategy for boosting vaccine immunogenicity. Here, we reported that the C-terminus of heat shock protein 60 (HSP60C) can activate mouse peritoneal macrophages to secret a series of cytokines, and phosphorylation of p38 mitogen-activated protein kinase (MAPK) and NF-κB p65 was involved in the pathway. We showed that the activation effect of HSP60C on macrophages was independent of toll-like receptor (TLR) 4 and the TLR-associated myeloide differentiation factor 88 (MyD88). Knockdown of lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) reduced the activation of HSP60C-induced macrophage p38 MAPK, NF-κB p65 and cytokine secretion to some extent. Finally, we found that HSP60C up-regulated the expression of LOX-1 on macrophages and ovalbumin (OVA) model antigen fused with HSP60C markedly enhanced OVA-specific IgG responses. Thus, our results unravel a novel LOX-1-dependent pathway by which HSP60C can effectively activate macrophages and APCs targeting based on LOX-1 interaction is a promising approach to improve vaccines.


Assuntos
Chaperonina 60/química , Chaperonina 60/metabolismo , Ativação de Macrófagos , Macrófagos Peritoneais/metabolismo , Receptores Depuradores Classe E/metabolismo , Animais , Formação de Anticorpos , Células CHO , Cricetinae , Cricetulus , Citocinas/metabolismo , Endocitose , Feminino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fator 88 de Diferenciação Mieloide/metabolismo , Ovalbumina/metabolismo , Ligação Proteica , Transdução de Sinais , Relação Estrutura-Atividade , Receptor 4 Toll-Like/metabolismo , Regulação para Cima , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
6.
Cell Commun Signal ; 17(1): 113, 2019 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-31477130

RESUMO

BACKGROUND: C-Type Lectin Domain Family 3 Member B (CLEC3B), is down-regulated in serum and tumor tissues in different cancers including hepatocellular carcinoma (HCC). However, the functions of CLEC3B in HCC remains elucidated. The aim of this study is to analyze the roles of CLEC3B in HCC. METHODS: The expression of genes was evaluated by immunohistochemistry, western blot, real-time PCR, enzyme-linked immunosorbent assays, and analysis on TCGA-LIHC database and gene expression omnibus. Transmission electron microscopy and immunofluorescence were applied to detect CLEC3B in exosomes. The function of exosomal CLEC3B in tumor progression were performed in vivo and in vitro. RESULTS: We determined that down-regulated CLEC3B in HCC indicated a poor prognosis. Exosomes derived from HCC with down-regulated CLEC3B promoted migration, invasion, epithelial-mesenchymal transition of both tumor cells and endothelial cells (ECs). Moreover, the downregulation CLEC3B in exosomes suppressed VEGF secretion in both HCC cells and ECs, and eventually inhibited angiogenesis. Mechanistically, CLEC3B-mediated VEGF expression in tumor cells and ECs depends on the activation of AMPK signal pathway. CONCLUSION: This study demonstrates that CLEC3B acts as a novel independent prognostic factor, and CLEC3B in exosomes might be a potential therapeutic target for hepatocellular carcinoma.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Carcinoma Hepatocelular/patologia , Regulação para Baixo , Lectinas Tipo C/genética , Neoplasias Hepáticas/patologia , Transdução de Sinais/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo , Animais , Carcinoma Hepatocelular/irrigação sanguínea , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/genética , Linhagem Celular Tumoral , Exossomos/metabolismo , Humanos , Masculino , Camundongos , Metástase Neoplásica , Neovascularização Patológica/genética , Prognóstico
7.
Mikrochim Acta ; 186(3): 166, 2019 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-30739206

RESUMO

Stable and low-cost carbon dots (C-dots) were prepared from polyethylenimine (PEI) by a hydrothermal method. It is found that the fluorescence of the C-dots (best measured at excitation/emission wavelengths of 365/473 nm) is quenched by selective oxidation of surface PEI by periodate but recovers in the presence of uric acid (UA). It is assumed that this is due to the selective reduction of the nitrone groups to hydroxylamine groups by UA. The findings were used to design a fluorometric method for determination of UA that has a 2.3 nM detection limit. This is lower than that of reported fluorometric and enzymatic assays. The performance of the method has been validated by determination of UA in samples of human saliva. It is found that the results agree well with those obtained by a commercial UA assay. Graphical abstract Schematic presentation of the polyethylenimine (PEI) carbon nanodots (C-dots) as a fluorescent probe for uric acid. Their fluorescence is quenched by periodate (IO4-) due to oxidative formation of nitrone groups, an subsequently restored due to reduction by uric acid (UA).


Assuntos
Fluorometria/métodos , Pontos Quânticos/química , Ácido Úrico/análise , Carbono , Fluorescência , Humanos , Limite de Detecção , Nanoestruturas , Nitrogênio , Saliva/química
8.
J Hepatol ; 68(6): 1191-1202, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29454068

RESUMO

BACKGROUND & AIMS: Aberrant oncogenic mRNA translation and protein O-linked ß-N-acetylglucosaminylation (O-GlcNAcylation) are general features during tumorigenesis. Nevertheless, whether and how these two pathways are interlinked remain unknown. Our previous study indicated that ribosomal receptor for activated C-kinase 1 (RACK1) promoted chemoresistance and growth in hepatocellular carcinoma (HCC). The aim of this study is to examine the role of RACK1 O-GlcNAcylation in oncogene translation and HCC carcinogenesis. METHODS: The site(s) of RACK1 for O-GlcNAcylation was mapped by mass spectrometry analysis. HCC cell lines were employed to examine the effects of RACK1 O-GlcNAcylation on the translation of oncogenic factors and behaviors of tumor cells in vitro. Transgenic knock-in mice were used to detect the role of RACK1 O-GlcNAcylation in modulating HCC tumorigenesis in vivo. The correlation of RACK1 O-GlcNAcylation with tumor progression and relapse were analyzed in clinical HCC samples. RESULTS: We found that ribosomal RACK1 was highly modified by O-GlcNAc at Ser122. O-GlcNAcylation of RACK1 enhanced its protein stability, ribosome binding and interaction with PKCßII (PRKCB), leading to increased eukaryotic translation initiation factor 4E phosphorylation and translation of potent oncogenes in HCC cells. Genetic ablation of RACK1 O-GlcNAcylation at Ser122 dramatically suppressed tumorigenesis, angiogenesis, and metastasis in vitro and in diethylnitrosamine (DEN)-induced HCC mouse model. Increased RACK1 O-GlcNAcylation was also observed in HCC patient samples and correlated with tumor development and recurrence after chemotherapy. CONCLUSIONS: These findings demonstrate that RACK1 acts as key mediator linking O-GlcNAc metabolism to cap-dependent translation during HCC tumorigenesis. Targeting RACK1 O-GlcNAcylation provides promising options for HCC treatment. LAY SUMMARY: O-GlcNAcylation of ribosomal receptor for activated C-kinase 1 at the amino acid serine122 promotes its stability, ribosome localization and interaction with the protein kinase, PKCßII, thus driving the translation of oncogenes and tumorigenesis of hepatocellular carcinoma. Increased O-GlcNAcylation of ribosomal receptor for activated C-kinase 1 is positively correlated with tumor growth, metastasis and recurrence in patients with hepatocellular carcinoma.


Assuntos
Carcinoma Hepatocelular/etiologia , Neoplasias Hepáticas/etiologia , Proteínas de Neoplasias/metabolismo , Receptores de Quinase C Ativada/metabolismo , Substituição de Aminoácidos , Animais , Carcinógenos/química , Carcinógenos/metabolismo , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Progressão da Doença , Glicosilação , Humanos , Neoplasias Hepáticas/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Camundongos Nus , Camundongos Transgênicos , Mutagênese Sítio-Dirigida , Proteínas de Neoplasias/química , Proteínas de Neoplasias/genética , Transplante de Neoplasias , Proteína Quinase C beta/metabolismo , Estabilidade Proteica , Receptores de Quinase C Ativada/química , Receptores de Quinase C Ativada/genética , Serina/química
9.
Virol J ; 15(1): 174, 2018 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-30424815

RESUMO

BACKGROUND: Rabies is a fatal disease that is preventable when post exposure prophylaxis (PEP) is administered in a timely fashion. CpG oligodeoxynucleotides (ODNs) can trigger cells that express Toll-like receptor 9, and their immunopotentiation activity in an inactivated aluminum-adjuvanted rabies vaccine for dogs has been identified using mouse and dog models. METHODS: A human diploid cell rabies vaccine (HDCV) of humans and a CpG ODNs with cross-immunostimulatory activity in humans and mice were used to evaluate the immunogenicity and protective efficacy of CpG ODN in a mouse model that simulates human PEP. RESULTS: HDCV combined with CpG ODN (HDCV-CpG) stimulated mice to produce rabies virus-specific neutralizing antibody (RVNA) earlier and increased the seroconversion rate. Compared with HDCV alone, either HDCV-1.25 µg CpG or HDCV-5 µg CpG increased the levels of RVNA. In particular, 5 µg CpG ODN per mouse significantly boosted the levels of RVNA compared with HDCV alone. IFN-γ producing splenocytes generated in the HDCV-5 µg CpG group were significantly increased compared to the group treated with HDCV alone. When the immunization regimen was reduced to three injections or the dose was reduced to half of the recommended HDCV combined with CpG ODN, the RVNA titers were still higher than those induced by HDCV alone. After viral challenge, 50% of mice immunized with a half-dose HDCV-CpG survived, while the survival rate of mice immunized with HDCV alone was 30%. CONCLUSIONS: The immunopotentiation activity of CpG ODNs for a commercially available human rabies vaccine was first evaluated in a mouse model on the basis of the Essen regimen. Our results suggest that the CpG ODN used in this study is a potential adjuvant to rabies vaccines for human use.


Assuntos
Adjuvantes Imunológicos/administração & dosagem , Oligodesoxirribonucleotídeos/imunologia , Profilaxia Pós-Exposição , Vacina Antirrábica/imunologia , Vírus da Raiva/imunologia , Raiva/imunologia , Animais , Anticorpos Antivirais/sangue , Modelos Animais de Doenças , Feminino , Humanos , Imunogenicidade da Vacina , Camundongos , Camundongos Endogâmicos BALB C , Oligodesoxirribonucleotídeos/administração & dosagem , Raiva/prevenção & controle , Vacina Antirrábica/administração & dosagem , Vacinas de Produtos Inativados/administração & dosagem , Vacinas de Produtos Inativados/imunologia
10.
Gastroenterology ; 150(5): 1183-1195.e16, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26855187

RESUMO

BACKGROUND & AIMS: C-type lectin-like receptor 2 (CLEC2) is a transmembrane receptor expressed on platelets and several hematopoietic cells. CLEC2 regulates platelet aggregation and the immune response. We investigated its expression and function in normal and transformed gastric epithelial cells from human tissues. METHODS: We performed tissue microarray analyses of gastric carcinoma samples collected from 96 patients who underwent surgery at Zhongshan Hospital of Fudan University in Shanghai, China and performed real-time polymerase chain reaction assays from an independent group of 60 patients; matched nontumor gastric mucosa tissues were used as the control. Full-length and mutant forms of CLEC2 were expressed in gastric cancer cell line (MGC80-3), or CLEC2 protein was knocked down using small-hairpin RNAs in gastric cancer cell lines (NCI-N87 and AGS). CLEC2 signaling was stimulated by incubation of cells with recombinant human podoplanin or an antibody agonist of CLEC2; cell migration and invasion were assessed by transwell and wound-healing assays. Immunoblot, immunofluorescence microscopy, and real-time polymerase chain reaction assays were used to measure expression of markers of the epithelial to mesenchymal transition and activation of signaling pathways. Immunoprecipitation experiments were performed with an antibody against spleen tyrosine kinase (SYK). Cells were injected into lateral tail vein of BALB/C nude mice; some mice were also given injections of the phosphoinositide 3-kinase (PI3K) inhibitor LY294002. Lung and liver tissues were collected and analyzed for metastases. RESULTS: Levels of CLEC2 were higher in nontumor gastric mucosa (control) than in gastric tumor samples. Levels of CLEC2 protein in gastric tumor tissues correlated with depth of tumor invasion, metastasis to lymph node, tumor TNM stage, and 5-year survival of patients. Activation of CLEC2 in gastric cancer cells reduced their invasive activities in vitro and expression of epithelial to mesenchymal transition markers; these tumor-suppressive effects of CLEC2 required SYK. CLEC2 and SYK interacted physically, and SYK maintained the stability of CLEC2 in cells. AGS cells with CLEC2 knockdown had increased levels of phosphorylated AKT and glycogen synthase kinase-3 beta, increased expression of Snail, reduced levels of E-cadherin, and formed more metastases in mice than AGS cells that expressed CLEC2; these knockdown changes were prevented by the PI3K inhibitor LY294002. Activation of CLEC2 in AGS cells reduced protein and messenger RNA levels of PI3K subunits p85 and p110; this effect was blocked by SYK inhibitor R406. Levels of CLEC2 and SYK proteins and messenger RNAs correlated in gastric tumor samples. CONCLUSIONS: CLEC2 suppresses metastasis of gastric cancer cells injected into mice, and prevents activation of AKT and glycogen synthase kinase-3 beta signaling, as well as invasiveness and expression of epithelial to mesenchymal transition markers in gastric cancer cell lines. CLEC2 prevents expression of PI3K subunits, in a SYK-dependent manner.


Assuntos
Movimento Celular , Classe Ia de Fosfatidilinositol 3-Quinase/metabolismo , Lectinas Tipo C/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Neoplasias Gástricas/enzimologia , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Classe Ia de Fosfatidilinositol 3-Quinase/genética , Transição Epitelial-Mesenquimal , Feminino , Regulação Neoplásica da Expressão Gênica , Glicogênio Sintase Quinase 3 beta/metabolismo , Humanos , Lectinas Tipo C/genética , Neoplasias Hepáticas/enzimologia , Neoplasias Hepáticas/prevenção & controle , Neoplasias Hepáticas/secundário , Neoplasias Pulmonares/enzimologia , Neoplasias Pulmonares/prevenção & controle , Neoplasias Pulmonares/secundário , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , Invasividade Neoplásica , Inibidores de Fosfoinositídeo-3 Quinase , Inibidores de Proteínas Quinases/farmacologia , Interferência de RNA , Transdução de Sinais/efeitos dos fármacos , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Quinase Syk/antagonistas & inibidores , Quinase Syk/genética , Quinase Syk/metabolismo , Fatores de Tempo , Transfecção , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Apoptosis ; 21(1): 96-109, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26481477

RESUMO

Heat shock proteins (HSPs) were originally identified as stress-responsive proteins and serve as molecular chaperones in different intracellular compartments. Translocation of HSPs to the cell surface and release of HSPs into the extracellular space have been observed during the apoptotic process and in response to a variety of cellular stress. Here, we report that UV irradiation and cisplatin treatment rapidly induce the expression of membrane-bound Hsp60, Hsp70, and Hsp90 upstream the phosphatidylserine exposure. Membrane-bound Hsp60, Hsp70 and Hsp90 could promote the release of IL-6 and IL-1ß as well as DC maturation by the evaluation of CD80 and CD86 expression. On the other hand, Hsp60, Hsp70 and Hsp90 on cells could facilitate the uptake of dying cells by bone marrow-derived dendritic cells. Lectin-like oxidized LDL receptor-1 (LOX-1), as a common receptor for Hsp60, Hsp70, and Hsp90, is response for their recognition and mediates the uptake of dying cells. Furthermore, membrane-bound Hsp60, Hsp70 and Hsp90 could promote the cross-presentation of OVA antigen from E.G7 cells and inhibition of the uptake of dying cells by LOX-1 decreases the cross-presentation of cellular antigen. Therefore, the rapid exposure of HSPs on dying cells at the early stage allows for the recognition by and confers an activation signal to the immune system.


Assuntos
Chaperonina 60/genética , Apresentação Cruzada , Células Dendríticas/imunologia , Proteínas de Choque Térmico HSP70/genética , Proteínas de Choque Térmico HSP90/genética , Proteínas Mitocondriais/genética , Animais , Apoptose/efeitos dos fármacos , Antígeno B7-1/genética , Antígeno B7-1/imunologia , Antígeno B7-2/genética , Antígeno B7-2/imunologia , Células CHO , Membrana Celular/efeitos dos fármacos , Membrana Celular/imunologia , Membrana Celular/metabolismo , Chaperonina 60/imunologia , Cricetulus , Células Dendríticas/citologia , Células Dendríticas/efeitos dos fármacos , Regulação da Expressão Gênica , Células HL-60 , Proteínas de Choque Térmico HSP70/imunologia , Proteínas de Choque Térmico HSP90/imunologia , Humanos , Interleucina-1beta/genética , Interleucina-1beta/imunologia , Interleucina-6/genética , Interleucina-6/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Mitocondriais/imunologia , Ovalbumina/farmacologia , Fosfatidilserinas/imunologia , Fosfatidilserinas/metabolismo , Ligação Proteica , Receptores Depuradores Classe E/genética , Receptores Depuradores Classe E/imunologia , Transdução de Sinais
12.
Anal Chem ; 87(9): 4925-32, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25853548

RESUMO

We have developed a simple, sensitive, and rapid fluorescence assay for the detection of cancer cells, based on "turn-on" retro-self-quenched fluorescence inside the cells. 1,3-Phenylenediamine resin (DAR) nanoparticles (NPs) containing rhodamine 6G (R6G) are conjugated with aptamer (apt) sgc8c to prepare sgc8c-R6GDAR NPs, while that containing rhodamine 101 (R101) are conjugated with TD05 for the preparation of TD05-R101DAR NPs. The sgc8c-R6GDAR and TD05-R101DAR NPs separately recognize CCRF-CEM and Ramos cells. The fluorescence intensities of the two apt-DAR NPs are both weak due to self-quenching, but they increase inside the cells as a result of release of the fluorophores from the apt-DAR NPs. The apt-DAR NPs' structure becomes less compact at low pH value, leading to the release of the fluorophores. The sgc8c-R6GDAR and TD05-R101DAR NPs allow detection of as low as 44 CCRF-CEM cells and 79 Ramos cells mL(-1), respectively, using a commercial reader within 10 min. Practicality of the two probes have been validated by the quantitation and identification of CCRF-CEM and Ramos cells spiked in blood samples through conventional fluorescence and flow cytometry analysis, with advantages of sensitivity, selectivity, and rapidity.


Assuntos
Aptâmeros de Nucleotídeos/química , Separação Celular/métodos , Fluorescência , Nanopartículas/química , Neoplasias/patologia , Polímeros/química , Animais , Humanos , Camundongos , Células NIH 3T3 , Neoplasias/diagnóstico , Células Tumorais Cultivadas
13.
Biochem Biophys Res Commun ; 463(4): 839-45, 2015 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-26056003

RESUMO

Hepatocellular carcinoma (HCC) remains the second leading cause of cancer-related death worldwide, and elevated rates of reactive oxygen species (ROS) have long been considered as a hallmark of almost all types of cancer including HCC. Protein kinase C alpha (PKCα), a serine/threonine kinase among conventional PKC family, is recognized as a major player in signal transduction and tumor progression. Overexpression of PKCα is commonly observed in human HCC and associated with its poor prognosis. However, how PKCα is involved in hepatocellular carcinogenesis remains not fully understood. In this study, we found that among the members of conventional PKC family, PKCα, but not PKCßI or ßII, promoted ROS production in HCC cells. PKCα stimulated generation of ROS by up-regulating DUOX2 at post-transcriptional level. Depletion of DUOX2 abrogated PKCα-induced activation of AKT/MAPK pathways as well as cell proliferation, migration and invasion in HCC cells. Moreover, the expression of DUOX2 and PKCα was well positively correlated in both HCC cell lines and patient samples. Collectively, our findings demonstrate that PKCα plays a critical role in HCC development by inducing DUOX2 expression and ROS generation, and propose a strategy to target PKCα/DUOX2 as a potential adjuvant therapy for HCC treatment.


Assuntos
Carcinoma Hepatocelular/enzimologia , Neoplasias Hepáticas/enzimologia , NADPH Oxidases/metabolismo , Proteína Quinase C-alfa/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Sequência de Bases , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Oxidases Duais , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Proteína Quinase C-alfa/genética , RNA Interferente Pequeno , Reação em Cadeia da Polimerase em Tempo Real
14.
Glycoconj J ; 32(1-2): 69-76, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25501264

RESUMO

The complicated delivery mechanism of group II membrane proteins makes it difficult to decide the fusion pattern of their extracellular domains (ECDs) with Fc moiety. In this study, we compared the expression of ECDs of three group II membrane proteins including CLEC-2, Dectin-1, and LOX-1 by fusion of Fc moiety. We found that the pattern of ECD-Fc fusion order produced the functionally active recombinant proteins while the pattern of Fc-ECD fusion order led to the altered glycosylation which abolished the binding of these proteins with their ligands. Meanwhile, our results indicated that the secretion of mouse Fc (mFc)-fused ECD of CLEC-2 was more efficient than that of rabbit Fc (rFc)-fused protein, while rFc moiety was more sensitive for detection compared with mFc moiety. Altogether, we provide a favorable fusion pattern of Fc moiety with the ECDs of group II transmembrane proteins.


Assuntos
Fragmentos Fc das Imunoglobulinas/metabolismo , Lectinas Tipo C/metabolismo , Processamento de Proteína Pós-Traducional , Animais , Células CHO , Membrana Celular/metabolismo , Cricetinae , Cricetulus , Glicosilação , Células HEK293 , Humanos , Fragmentos Fc das Imunoglobulinas/genética , Lectinas Tipo C/química , Lectinas Tipo C/genética , Camundongos , Estrutura Terciária de Proteína , Transporte Proteico , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Receptores Depuradores Classe E/química , Receptores Depuradores Classe E/genética , Receptores Depuradores Classe E/metabolismo
15.
Anal Bioanal Chem ; 406(27): 6917-23, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24553661

RESUMO

In this study, highly hydrophilic and photoluminescent sheets of reduced graphene oxide decorated with carbon dots (C-dots@RGO), methylene blue (MB), and a probe DNA have been used for the detection of DNA. The photoluminescence of C-dots@RGO is quenched by MB, which is restored in the presence of a target DNA. The combination of the C-dots@RGO, MB, and a DNA probe is selective for perfectly matched DNA over mismatched DNA, mainly because relative to single-stranded DNA, double-stranded DNA intercalates more strongly with MB, but interacts more weakly with RGO. In the presence of a target DNA, MB intercalates with the as-formed double-stranded DNA and is released from the surface of C-dots@RGO, leading to "turn-on" photoluminescence. The practicality of this assay has been validated by the determination of tumor suppressor gene BRCA1, with linearity over the concentration range from 25 to 250 nM and a limit of detection (LOD, at a signal-to-noise ratio of 3) of 14.6 nM. The C-dots@RGO probe provides higher specificity towards target DNA than towards common salts, carbohydrates, amino acids, and proteins found in real samples. Having the advantages of simplicity, cost-effectiveness, selectivity, and sensitivity, the DNA-P/C-dots@RGO-MB probe on microwells has been successfully employed for the detection of DNA, suggesting its potential for multiple analyses of DNA targets when various DNA probes are employed.


Assuntos
Sondas de DNA , Sequência de Bases , Luminescência , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Dados de Sequência Molecular
16.
J Agric Food Chem ; 72(23): 13164-13174, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38819965

RESUMO

Obtaining a microorganism strain with a broad-spectrum resistance property and highly efficient antifungal activity is important to the biocontrol strategy. Herein, a marine Streptomyces sp. HNBCa1 demonstrated a broad-spectrum resistance to 17 tested crop pathogenic fungi and exhibited a high biocontrol efficiency against mango anthracnose and banana fusarium wilt. To uncover the critical bioactive secondary metabolites basis, genome assembly and annotation, metabolomic analysis, and a semipreparative HPLC-based activity-guide method were employed. Finally, geldanamycin and ectoine involved in codifferential secondary metabolites were also found to be related to biosynthetic gene clusters in the genome of HNBCa1. Reblastatin and geldanamycin were uncovered in response to broad-spectrum resistance to the 17 crop pathogenic fungi. Our results suggested that reblastatin and geldanamycin were critical to maintaining the broad-spectrum resistance property and highly efficient antifungal activity of HNBCa1, which could be further developed as a biological control agent to control crop fungal diseases.


Assuntos
Fusarium , Lactamas Macrocíclicas , Doenças das Plantas , Metabolismo Secundário , Streptomyces , Streptomyces/genética , Streptomyces/metabolismo , Streptomyces/química , Doenças das Plantas/microbiologia , Lactamas Macrocíclicas/farmacologia , Lactamas Macrocíclicas/metabolismo , Lactamas Macrocíclicas/química , Fusarium/efeitos dos fármacos , Benzoquinonas/farmacologia , Benzoquinonas/metabolismo , Benzoquinonas/química , Fungos/genética , Antifúngicos/farmacologia , Antifúngicos/metabolismo , Antifúngicos/química
17.
Medicine (Baltimore) ; 103(6): e37128, 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38335434

RESUMO

Early recognition of malnutrition is essential to improve the prognosis of older patients with hip fracture. The Nutritional Risk Screening 2002 (NRS-2002), the Short-Form Mini Nutritional Assessment (MNA-SF) and the Global Leadership Initiative on Malnutrition (GLIM) are widely used in malnutrition diagnosis. However, criteria for predicting postoperative hip joint motor function in older patients with hip fractures are still necessary. The objective of this study was to select the most appropriate criteria from the NRS-2002, the MNA-SF and the GLIM in predicting the postoperative hip joint motor function recovery 1 year after surgery. This retrospective observational study included 161 patients aged ≥ 65 years with hip fractures. The nutritional status of patients was determined by the NRS-2002, MNA-SF and GLIM. The Harris hip joint score (HHS), the primary outcome of this study, was used to evaluate hip joint motor function. HHS was classified as excellent (HHS > 75) or non-excellent outcomes (HHS ≤ 75). Logistic regression models for hip joint motor function recovery were constructed. Both the receiver operating characteristic curve and the decision curve analysis were used to select the most predictive criteria. The overall mean age of the 161 patients was 77.90 ±â€…8.17. As a result, NRS-2002 (OR:0.06, 95%CI [0.01, 0.17]), MNA-SF (OR:0.05, 95%CI [0.00, 0.23]) and GLIM (OR of moderate: 0.03, 95%CI [0.01, 0.11]; OR of severe: 0.02 [0.00, 0.07]) were predictive for recovery of hip joint motor function. Additionally, both the area under curve of the receiver operating characteristic curve (NRS-2002: 81.2 [73.8, 88.6], MNA-SF: 76.3 [68.5, 84.2], GLIM: 86.2 [79.6,92.8]) and the decision curve analysis showed the GLIM was better than others. Compared with NRS-2002 and MNA-SF, GLIM was a more suitable nutritional assessment criteria to predict the postoperative recovery of hip joint motor function for older patients with hip fracture 1 year after surgery.


Assuntos
Fraturas do Quadril , Desnutrição , Humanos , Idoso , Estado Nutricional , Estudos Retrospectivos , Recuperação de Função Fisiológica , Liderança , Desnutrição/diagnóstico , Avaliação Nutricional , Fraturas do Quadril/cirurgia
18.
Nutrients ; 15(20)2023 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-37892439

RESUMO

To investigate the role of gastrointestinal (GI) polysaccharide fermentation in alleviating constipation, two polysaccharide fractions were isolated from a soluble fiber extract with determined anti-constipation activity: a 2.04 kDa neutral fraction (SSP-1) contained 99.29% glucose, and a 41.66 kDa acidic fraction (SSP-2) contained 63.85% uronic acid. After mice were given loperamide for 14 d to induce constipation, the GI transit rate increased significantly in the SSP-1 group (p < 0.05) but not in the SSP-2 group. The stool weight in the SSP-2 group was significantly higher than that in SSP-1 (383.60 mg vs. 226.23 mg) (p < 0.05). Both SSP-1 and SSP-2 groups had significantly increased serum gastrin and motilin levels (p < 0.05) and changes in their fecal short-chain fatty acid (SCFA) profiles, while SSP-1 showed better fermentation properties than SSP-2 in terms of statistically higher fecal contents of acetic acid and total SCFAs (p < 0.05). Bioinformatic analysis indicated that SSP-1 upregulated bacteria such as Oscillibacter to improve SCFA metabolism and stimulate GI hormone secretion, while SSP-2 had less influence on the gut microbiota. These results suggest that the neutral polysaccharide with superior GI fermentation properties exerted beneficial effects on constipation, while the less fermentable pectic fraction might act as a stool-bulking agent.


Assuntos
Constipação Intestinal , Loperamida , Camundongos , Animais , Loperamida/efeitos adversos , Constipação Intestinal/induzido quimicamente , Constipação Intestinal/tratamento farmacológico , Polissacarídeos/efeitos adversos , Ácidos Graxos Voláteis/análise , Fezes/microbiologia
19.
Foods ; 12(8)2023 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-37107415

RESUMO

The influence of steaming treatment on the soluble dietary fiber (SDF) of sweet potato was investigated. The SDF content increased from 2.21 to 4.04 g/100 g (in dry basis) during 20 min of steaming. The microcosmic morphology of the fractured cell wall indicated the release of SDF components during steaming. The SDF from fresh (SDF-F) and 20 min steamed (SDF-S) sweet potato was characterized. The neutral carbohydrates and uronic acid levels in SDF-S were significantly higher than SDF-F (59.31% versus 46.83%, and 25.36% versus 9.60%, respectively) (p < 0.05). The molecular weight of SDF-S was smaller than SDF-F (5.32 kDa versus 28.79 kDa). The probiotic property was evaluated by four Lactobacillus spp. fermentation in vitro with these SDF as carbon source, using inulin as the references. SDF-F showed the best proliferation effects on the four Lactobacillus spp. in terms of the OD600 and pH in cultures, and the highest production of propanoic acid and butyric acid after 24 h fermentation. SDF-S presented higher Lactobacillus proliferation effects, but slight lower propanoic acid and butyric acid production than inulin. It was concluded that 20 min of steaming released SDF with inferior probiotic properties, which might derive from the degraded pectin, cell wall components, and resistant dextrin.

20.
Cell Signal ; 110: 110834, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37532137

RESUMO

FBN1 mutation promotes the degeneration of microfibril structures and extracellular matrix (ECM) integrity in the tunica media of the aorta in Marfan syndrome. However, whether FBN1 modulates cervical artery dissection (CAD) development and the potential molecular mechanisms of abnormal FBN1 in CAD remains elusive. In this study, FBN1 deficiency participated in the development of CAD and influenced the proliferation, apoptosis, and migration of vascular smooth muscle cells. FBN1 knockout induced alternations in mRNA levels of the transcriptome, protein expression of the proteome, and abundance of N-glycosylation of the N-glycoproteome. Comprehensive analysis of multiple omics showed up-regulation in mRNA levels of ECM proteins; yet, both the ECM protein levels and relative abundance of N-glycosylation were decreased. Moreover, we performed in vivo experiments to confirm the altered glycosylation of proteins in vascular smooth muscle cells. In conclusion, FBN1 deletion in vascular smooth muscle cells can result in altered N-glycosylation of ECM protein, which were critical for the stability of ECM and the process of CAD. This may open the way for a novel therapeutic strategy to treat people with CAD.


Assuntos
Proteínas da Matriz Extracelular , Fibrilina-1 , Músculo Liso Vascular , Animais , Ratos , Aorta/metabolismo , Matriz Extracelular/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Fibrilina-1/genética , Fibrilina-1/metabolismo , Glicosilação , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , RNA Mensageiro/metabolismo
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