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1.
Am J Physiol Heart Circ Physiol ; 319(2): H306-H319, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32618513

RESUMO

Dilated cardiomyopathy (DCM) is clinically characterized by dilated ventricular cavities and reduced ejection fraction, leading to heart failure and increased thromboembolic risk. Mutations in thin-filament regulatory proteins can cause DCM and have been shown in vitro to reduce contractility and myofilament Ca2+-affinity. In this work we have studied the functional consequences of mutations in cardiac troponin T (R131W), cardiac troponin I (K36Q) and α-tropomyosin (E40K) using adenovirally transduced isolated guinea pig left ventricular cardiomyocytes. We find significantly reduced fractional shortening with reduced systolic Ca2+. Contraction and Ca2+ reuptake times were slowed, which contrast with some findings in murine models of myofilament Ca2+ desensitization. We also observe increased sarcoplasmic reticulum (SR) Ca2+ load and smaller fractional SR Ca2+ release. This corresponds to a reduction in SR Ca2+-ATPase activity and increase in sodium-calcium exchanger activity. We also observe dephosphorylation and nuclear translocation of the nuclear factor of activated T cells (NFAT), with concordant RAC-α-serine/threonine protein kinase (Akt) phosphorylation but no change to extracellular signal-regulated kinase activation in chronically paced cardiomyocytes expressing DCM mutations. These changes in Ca2+ handling and signaling are common to all three mutations, indicating an analogous pathway of disease pathogenesis in thin-filament sarcomeric DCM. Previous work has shown that changes to myofilament Ca2+ sensitivity caused by DCM mutations are qualitatively opposite from hypertrophic cardiomyopathy (HCM) mutations in the same genes. However, we find several common pathways such as increased relaxation times and NFAT activation that are also hallmarks of HCM. This suggests more complex intracellular signaling underpinning DCM, driven by the primary mutation.NEW & NOTEWORTHY Dilated cardiomyopathy (DCM) is a frequently occurring cardiac disorder with a degree of genetic inheritance. We have found that DCM mutations in proteins that regulate the contractile machinery cause alterations to contraction, calcium-handling, and some new signaling pathways that provide stimuli for disease development. We have used guinea pig cells that recapitulate human calcium-handling and introduced the mutations using adenovirus gene transduction to look at the initial triggers of disease before remodeling.


Assuntos
Sinalização do Cálcio , Cardiomiopatia Dilatada/genética , Proteínas dos Microfilamentos/genética , Mutação , Contração Miocárdica , Miócitos Cardíacos/enzimologia , Fatores de Transcrição NFATC/metabolismo , Proteína Oncogênica v-akt/metabolismo , Função Ventricular Esquerda , Animais , Cardiomiopatia Dilatada/metabolismo , Cardiomiopatia Dilatada/fisiopatologia , Cardiomiopatia Hipertrófica/genética , Cardiomiopatia Hipertrófica/metabolismo , Cardiomiopatia Hipertrófica/fisiopatologia , Células Cultivadas , Predisposição Genética para Doença , Cobaias , Masculino , Proteínas dos Microfilamentos/metabolismo , Fenótipo , Retículo Sarcoplasmático/metabolismo , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/metabolismo , Trocador de Sódio e Cálcio/metabolismo , Tropomiosina/genética , Tropomiosina/metabolismo , Troponina I/genética , Troponina I/metabolismo , Troponina T/genética , Troponina T/metabolismo
2.
Oxid Med Cell Longev ; 2020: 6286984, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32051732

RESUMO

Folic acid- (FA-) induced kidney injury is characterized by the tubule damage due to the disturbance of the antioxidant system and subsequent interstitial fibrosis. FG-4592 is an inhibitor of prolyl hydroxylase of hypoxia-inducible factor (HIF), an antioxidant factor. The present study investigated the protective role of FG-4592 pretreatment at the early stage of the kidney injury and long-term impact on the progression of renal fibrosis. FG-4592 was administrated two days before FA injection in mice. On the second day after FA injection, the mice with FG-4592 pretreatment showed an improved renal function, compared with those without FG-4592 pretreatment, indicated by biochemical and histological parameters; meanwhile, the cellular content of iron, malondialdehyde, and 4-hydroxynonenal histologically decreased, implying the suppression of iron accumulation and lipid peroxidation. Simultaneously, upregulation of HIF-1α was found, along with Nrf2 activation, which was reflected by increased nuclear translocation and high-expression of downstream proteins, including heme-oxygenase1, glutathione peroxidase4, and cystine/glutamate transporter, as well as ferroportin. Correspondingly, the elevated levels of antioxidative enzymes and glutathione, as well as reduced iron accumulation, were observed, suggesting a lower risk of occurrence of ferroptosis with FG-4592 pretreatment. This was confirmed by reversed pathological parameters and improved renal function in FA-treated mice with the administration of ferrostatin-1, a specific ferroptosis inhibitor. Furthermore, a signal pathway study indicated that Nrf2 activation was associated with increased phosphorylation of Akt and GSK-3ß, verified by the use of an inhibitor of the PI3K that phosphorylates Akt. Moreover, FG-4592 pretreatment also decreased macrophage infiltration and expression of inflammatory factors TNF-α and IL-1ß. On the 14th day after FA injection, FG-4592 pretreatment decreased collagen deposition and expression of fibrosis biomarkers. These findings suggest that the protective role of FG-4592 pretreatment is achieved mainly by decreasing ferroptosis at the early stage of FA-induced kidney injury via Akt/GSK-3ß-mediated Nrf2 activation, which retards the fibrosis progression.


Assuntos
Lesão Renal Aguda/tratamento farmacológico , Glicina/análogos & derivados , Glicogênio Sintase Quinase 3 beta/metabolismo , Isoquinolinas/uso terapêutico , Rim/patologia , Fator 2 Relacionado a NF-E2/metabolismo , Proteína Oncogênica v-akt/metabolismo , Lesão Renal Aguda/induzido quimicamente , Animais , Cicloexilaminas/administração & dosagem , Ferroptose/efeitos dos fármacos , Ácido Fólico/administração & dosagem , Glicina/farmacologia , Glicina/uso terapêutico , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/antagonistas & inibidores , Isoquinolinas/farmacologia , Rim/efeitos dos fármacos , Peroxidação de Lipídeos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Estresse Oxidativo , Fenilenodiaminas/administração & dosagem , Transdução de Sinais
3.
Life Sci ; 245: 117363, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-32001271

RESUMO

AIMS: CircRNAs are emerging as a novel class of non-coding RNAs that play crucial roles in malignant cancer. However, the expression profile and potential mechanism of circRNAs in gliomas remain uncharacterized. In this study, we aim to investigate abnormally expressed circRNAs during glioma pathogenesis and find out potential therapeutic targets for treatment. MAIN METHODS: The glioma cell lines (U251 and SHG-44), 32 pairs of glioma tissue samples and adjacent control samples were used in this study. Microarray and bioinformatics tools were performed to identify circRNAs expression in glioma. QRT-PCR experiment was used to confirm gene expression. CCK-8 and transwell assay were conducted to measure cell viability and invasion. Dual-luciferase reporter experiment was performed to identify target bindings between RNAs. KEY FINDINGS: The circRNA circ_0037655 was highly expressed in both glioma tissues and cell lines (U251 and SHG-44) compared to control. Inhibition of circ_0037655 could suppress the viability and invasion of glioma cells. Circ_0037655 acts as a sponge of miR-214 and inhibition of miR-214 could reverse cell viability and invasion ability induced by si-circ_0037655. Over-expression of miR-214 could reduce the expression of p-Akt (PI3K pathway indicator). SIGNIFICANCE: This study identified circRNAs expression profile in gliomas and revealed that circ_0037655 could promote glioma progression by regulating miR-214/PI3K signaling, which may provide new therapeutic approach for gliomas.


Assuntos
Glioma/metabolismo , MicroRNAs/metabolismo , Proteína Oncogênica v-akt/metabolismo , RNA Circular/metabolismo , RNA Neoplásico/metabolismo , Transdução de Sinais , Animais , Linhagem Celular Tumoral , Glioma/genética , Humanos , Camundongos Nus , Transplante de Neoplasias , Análise de Sequência com Séries de Oligonucleotídeos , RNA Circular/genética , RNA Neoplásico/genética , Reação em Cadeia da Polimerase em Tempo Real , Transcriptoma
4.
Phytother Res ; 34(3): 591-600, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32011040

RESUMO

Icariin (ICA) is obtained from Epimedium brevicornu maxim and exploited to remedy miscellaneous cancers. But the role of ICA in medulloblastoma remains hazy. The research delved into the antitumor activity of ICA in medulloblastoma DAOY cells. ICA with diverse concentrations was utilized to stimulate DAOY cells, and the biological functions of ICA in medulloblastoma DAOY cells were examined. Then, the relative SPARC expression was determined in ICA-managed DAOY cells, and the pc-SPARC vector was transfected into DAOY cells to further probe the influence of SPARC and JAK1/STAT3 and PI3K/AKT pathways in ICA-managed DAOY cells. A xenograft model was established to investigate the function of ICA in vivo. ICA restrained cell viability, expedited apoptosis, prohibited cell migration and invasion, and meanwhile affected the associative factors expression in DAOY cells. Additionally, SPARC expression was declined in ICA-stimulated DAOY cells. Overexpressed SPARC reversed the functions of ICA in above-involved cell behaviors of DAYO cells and the correlative protein levels. Besides, ICA notably frustrated JAK1/STAT3 and PI3K/AKT activations in DAOY cells. Beyond that, ICA prohibited tumor formation in vivo. The results concluded that ICA exhibited the antitumor activity in DAOY cells via decreasing SPARC and inactivating JAK1/STAT3 and PI3K/AKT pathways.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Neoplasias Cerebelares/tratamento farmacológico , Flavonoides/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Meduloblastoma/tratamento farmacológico , Osteonectina/metabolismo , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Humanos , Janus Quinase 1/genética , Janus Quinase 1/metabolismo , Invasividade Neoplásica/prevenção & controle , Proteína Oncogênica v-akt/genética , Proteína Oncogênica v-akt/metabolismo , Osteonectina/genética , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo
5.
Am J Physiol Endocrinol Metab ; 318(2): E173-E183, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-31794259

RESUMO

Growth factor receptor-bound protein 10 (Grb10) is an adaptor protein that binds to the insulin receptor, upon which insulin signaling and action are thought to be inhibited. Grb10 is also a substrate for the mechanistic target of rapamycin complex 1 (mTORC1) that mediates its feedback inhibition on phosphatidylinositide 3-kinase (PI3K)/Akt signaling. To characterize the function of Grb10 and its regulation by mTORC1 in human muscle, primary skeletal muscle cells were isolated from healthy lean young men and then induced to differentiate into myotubes. Knockdown of Grb10 enhanced insulin-induced PI3K/Akt signaling and glucose uptake in myotubes, reinforcing the notion underlying its function as a negative regulator of insulin action in human muscle. The increased insulin responsiveness in Grb10-silenced myotubes was associated with a higher abundance of the insulin receptor. Furthermore, insulin and amino acids independently and additively stimulated phosphorylation of Grb10 at Ser476. However, acute inhibition of mTORC1 with rapamycin blocked Grb10 Ser476 phosphorylation and repressed a negative-feedback loop on PI3K/Akt signaling that increased myotube responsiveness to insulin. Chronic rapamycin treatment reduced Grb10 protein abundance in conjunction with increased insulin receptor protein levels. Based on these findings, we propose that mTORC1 controls PI3K/Akt signaling through modulation of insulin receptor abundance by Grb10. These findings have potential implications for obesity-linked insulin resistance, as well as clinical use of mTORC1 inhibitors.


Assuntos
Proteína Adaptadora GRB10/fisiologia , Insulina/fisiologia , Alvo Mecanístico do Complexo 1 de Rapamicina/fisiologia , Fibras Musculares Esqueléticas/fisiologia , Transdução de Sinais/genética , Transdução de Sinais/fisiologia , Aminoácidos/farmacologia , Células Cultivadas , Proteína Adaptadora GRB10/genética , Técnicas de Silenciamento de Genes , Glucose/metabolismo , Humanos , Insulina/farmacologia , Masculino , Alvo Mecanístico do Complexo 1 de Rapamicina/genética , Proteína Oncogênica v-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação/efeitos dos fármacos , Receptor de Insulina/metabolismo , Adulto Jovem
6.
Oxid Med Cell Longev ; 2019: 7591840, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31885814

RESUMO

Oxidative stress is implicated in a wide range of intestinal disorders and closely associated with their pathological processes. Resveratrol (RSV), a plant extract, plays a vital role in protecting various organs in vitro and in vivo. However, the benefits of RSV are controversial, and underlying mechanisms for its antioxidant effects on intestinal epithelial cells remain unclear. In this study, we evaluated the effects of RSV on oxidative stress induced by H2O2 in IPEC-J2 cells. We found that pretreatment with RSV significantly increased cell viability; increased expression levels of tight junction (TJ) proteins (claudin-1, occludin, and ZO-1); improved activities of superoxide dismutase-1 (SOD-1), catalase (CAT), and glutathione peroxidase (GSH-Px); and decreased intracellular reactive oxygen species (ROS) levels and apoptosis induced by H2O2 (P < 0.05). In addition, RSV upregulated Akt phosphorylation, Nrf2 phosphorylation, and expression levels of antioxidant genes HO-1, SOD-1, and CAT in a dose-dependent manner (P < 0.05) under oxidative stress. Knockdown of Nrf2 by short-hairpin RNA (shRNA) abrogated RSV-mediated protection against H2O2-induced apoptosis, RSV-induced increase of TJ protein levels, and antioxidant gene expression (SOD-1, CAT, and GSH-Px) (P < 0.05). Consistent with Nrf2 knockdown, the PI3K/Akt inhibitor LY294002 significantly suppressed RSV-induced Nrf2 phosphorylation and RSV-induced increase of TJ protein levels and antioxidant gene expression under H2O2 treatment (P < 0.05). Collectively, these results demonstrate that RSV can directly protect IPEC-J2 cells against oxidative stress through the PI3K/Akt-mediated Nrf2 signaling pathway, suggesting that RSV may be an effective feed additive against intestinal damage in livestock production.


Assuntos
Antioxidantes/farmacologia , Mucosa Intestinal/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Resveratrol/farmacologia , Junções Íntimas/metabolismo , Animais , Claudina-1/metabolismo , Regulação da Expressão Gênica , Células HEK293 , Humanos , Peróxido de Hidrogênio/metabolismo , Mucosa Intestinal/patologia , Fator 2 Relacionado a NF-E2/genética , Proteína Oncogênica v-akt/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , RNA Interferente Pequeno/genética , Transdução de Sinais , Suínos , Junções Íntimas/patologia
7.
Cell Mol Biol (Noisy-le-grand) ; 65(7): 105-110, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31880526

RESUMO

Overexpression of p-glycoprotein (p-gp) is the main cause of multidrug resistance and chemotherapy failure in leukemia. Sodium azulene sulfonate (SAS) was used to reverse the multidrug resistance of human leukemia adriamycin-resistant strain K562/A02, and the underlying mechanism was investigated. Human leukemia cell line K562 and drug-resistant cell line K562/A02 in logarithmic phase were used in this study. After 48 hours of treatment of K562/A02 cells with SAS, the intrinsic cytotoxicity of chlorogenic acid and its sensitivity to adriamycin (ADM) were determined with MTT assay. The degree of reversal was calculated. Using ADM accumulation and rhodamine 123 efflux experiments, the average fluorescence intensity of ADM and rhodamine 123 (Rh123) in chlorogenic acid-treated K562/A02 cells was determined flow cytometrically. The expressions of p-gp, t-Akt and p-Akt in K562/A02 cells were assayed using Western blotting. SAS had almost no cytotoxic effect, and the degree of inhibition was only about 20% at the highest concentration of 100 mu-M. The EC50 of MDR reversal by SAS was in the nano range (539±37nM), and it had a high selectivity index for normal cells (>185). The accumulation of ADM in drug-resistant cells was increased significantly after treatment with 1 and 5 mu-M SAS, while the efflux of Rh123 was significantly inhibited, suggesting that SAS reversed MDR by inhibiting p-gp function. Western blotting experiments showed that SAS downregulated the expression of p-gp by inhibiting PI3K/Akt signaling pathway. This contributed to the reversal of drug resistance.SAS effectively reverses multidrug resistance in vitro by inhibiting the function of p-gp in K562/A02 cells, through a mechanism involving downregulation of the P13K/Akt signaling pathway. Therefore, SAS may be a potential candidate drug for reversal of MDR.


Assuntos
Azulenos/farmacologia , Doxorrubicina/farmacologia , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Transporte Biológico/efeitos dos fármacos , Western Blotting , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos , Humanos , Células K562 , Proteína Oncogênica v-akt/metabolismo , Rodamina 123/metabolismo
8.
Oxid Med Cell Longev ; 2019: 1681972, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31737164

RESUMO

Fusobacterium nucleatum (F. nucleatum) plays key roles in the initiation and progression of periodontitis. However, the pathogenic effect of F. nucleatum on human oral tissues and cells has not been fully evaluated. In this study, we aimed to analyze the pathogenic effects of F. nucleatum on human gingival fibroblasts (GFs) and clarify the potential mechanisms. RNA-sequencing analysis confirmed that F. nucleatum significantly altered the gene expression of GF as the stimulation time increased. Cell counting and EdU-labeling assays indicated that F. nucleatum inhibited GF proliferation and promoted cell apoptosis in a time- and dose-dependent manner. In addition, cell apoptosis, intracellular reactive oxygen species (ROS) generation, and proinflammatory cytokine production were dramatically elevated after F. nucleatum stimulation. Furthermore, we found that the AKT/MAPK and NF-κB signaling pathways were significantly activated by F. nucleatum infection and that a large number of genes related to cellular proliferation, apoptosis, ROS, and inflammatory cytokine production downstream of AKT/MAPK and NF-κB signaling pathways were significantly altered in F. nucleatum-stimulated GFs. These findings suggest that F. nucleatum inhibits GF proliferation and promotes cell apoptosis, ROS generation, and inflammatory cytokine production partly by activating the AKT/MAPK and NF-κB signaling pathways. Our study opens a new window for understanding the pathogenic effects of periodontal pathogens on the host oral system.


Assuntos
Fibroblastos/metabolismo , Infecções por Fusobacterium/metabolismo , Fusobacterium nucleatum/fisiologia , Gengiva/patologia , Periodontite/metabolismo , Adulto , Apoptose , Células Cultivadas , Citocinas/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Feminino , Fibroblastos/patologia , Humanos , Mediadores da Inflamação/metabolismo , Masculino , NF-kappa B/metabolismo , Proteína Oncogênica v-akt/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais
9.
Parasit Vectors ; 12(1): 542, 2019 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-31727141

RESUMO

BACKGROUND: Larvae of Echinococcus granulosus (sensu lato) dwell in host organs for a long time but elicit only a mild inflammatory response, which indicates that the resolution of host inflammation is necessary for parasite survival. The recruitment of alternatively activated macrophages (AAMs) has been observed in a variety of helminth infections, and emerging evidence indicates that AAMs are critical for the resolution of inflammation. However, whether AAMs can be induced by E. granulosus (s.l.) infection or thioredoxin peroxidase (TPx), one of the important molecules secreted by the parasite, remains unclear. METHODS: The activation status of peritoneal macrophages (PMs) derived from mice infected with E. granulosus (sensu stricto) was analyzed by evaluating the expression of phenotypic markers. PMs were then treated in vivo and in vitro with recombinant EgTPx (rEgTPx) and its variant (rvEgTPx) in combination with parasite excretory-secretory (ES) products, and the resulting activation of the PMs was evaluated by flow cytometry and real-time PCR. The phosphorylation levels of various molecules in the PI3K/AKT/mTOR pathway after parasite infection and antigen stimulation were also detected. RESULTS: The expression of AAM-related genes in PMs was preferentially induced after E. granulosus (s.s.) infection, and phenotypic differences in cell morphology were detected between PMs isolated from E. granulosus (s.s.)-infected mice and control mice. The administration of parasite ES products or rEgTPx induced the recruitment of AAMs to the peritoneum and a notable skewing of the ratio of PM subsets, and these effects are consistent with those obtained after E. granulosus (s.s.) infection. ES products or rEgTPx also induced PMs toward an AAM phenotype in vitro. Interestingly, this immunomodulatory property of rEgTPx was dependent on its antioxidant activity. In addition, the PI3K/AKT/mTOR pathway was activated after parasite infection and antigen stimulation, and the activation of this pathway was suppressed by pre-treatment with an AKT/mTOR inhibitor. CONCLUSIONS: This study demonstrates that E. granulosus (s.s.) infection and ES products, including EgTPx, can induce PM recruitment and alternative activation, at least in part, via the PI3K/AKT/mTOR pathway. These results suggest that EgTPx-induced AAMs might play a key role in the resolution of inflammation and thereby favour the establishment of hydatid cysts in the host.


Assuntos
Echinococcus granulosus/imunologia , Macrófagos Peritoneais/imunologia , Proteína Oncogênica v-akt/metabolismo , Peroxirredoxinas/imunologia , Fosfatidilinositol 3-Quinases/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Animais , Equinococose/parasitologia , Echinococcus granulosus/enzimologia , Feminino , Ativação de Macrófagos/efeitos dos fármacos , Macrófagos Peritoneais/efeitos dos fármacos , Macrófagos Peritoneais/parasitologia , Camundongos , Camundongos Endogâmicos BALB C , Peroxirredoxinas/farmacologia , Fenótipo , Fosforilação , Transdução de Sinais , Organismos Livres de Patógenos Específicos
10.
BMC Cancer ; 19(1): 1035, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31675995

RESUMO

BACKGROUND: ß-arrestin-2(Arr2) functions as an anti-apoptotic factor and affects cell proliferation, but its downstream molecular pathway in endometrial carcinoma (EC) is still unclear. This study aimed to investigate the effects of the stable overexpression of Arr2 on the proliferation and apoptosis of human EC heterotransplants and the expression of associated molecules, including Toll-like receptor 2(TLR2), serine-threonine kinase Akt (Akt), glycogen synthase kinase-3ß(GSK3ß) and some typical inflammatory cytokines such as NF-κB p56, TNF-α and IL-6 & IL-8. METHODS: Human EC cell line Ishikawa, stably transfected with Arr2 full-length plasmid, was injected subcutaneously into nude mice. They were treated with 0, 10, 20 mg/kg paclitaxel and the volume and weight of the tumor tissue were measured and calculated. The necrotic index were assessed by H&E staining and microscopic observation. The levels of caspase-3, caspase-9, TLR2, NF-κB p56, Akt, GSK3ß were measured by western blot, and the levels of TNF-α, IL-6, IL-8 were measured by real-time PCR. RESULTS: We found that Arr2 overexpression promoted the growth of human EC heterotransplants. Arr2 attenuated the promotion of caspase-3 and caspase-9 by paclitaxel and mediated the increase of TLR2 and several inflammatory cytokines. The levels of Akt and GSK3ß were not affected. CONCLUSION: Arr2 overexpression was associated with the increase of TLR2 and several inflammatory factors, meanwhile inhibited paclitaxel-induced anti-tumor effect on human EC heterotransplants.


Assuntos
Receptor 2 Toll-Like/metabolismo , beta-Arrestina 2/metabolismo , Animais , Apoptose , Linhagem Celular Tumoral , Citocinas/metabolismo , Neoplasias do Endométrio , Feminino , Regulação Neoplásica da Expressão Gênica , Glicogênio Sintase Quinase 3 beta/metabolismo , Xenoenxertos , Humanos , Mediadores da Inflamação/metabolismo , Camundongos , Camundongos Nus , NF-kappa B/metabolismo , Transplante de Neoplasias , Proteína Oncogênica v-akt/genética , Proteína Oncogênica v-akt/metabolismo , Transdução de Sinais , Receptor 2 Toll-Like/genética , Neoplasias Uterinas , beta-Arrestina 2/genética
11.
Life Sci ; 235: 116837, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31493481

RESUMO

AIMS: This study aimed to evaluate the effects of the sigma-1 receptor (S1R) on atrial fibrillation (AF) susceptibility in rats. MAIN METHODS: Rats were randomly assigned into three groups for intraperitoneal treatment with saline (CTL group), BD1047 (an antagonist of the S1R, BD group) or BD1047 plus fluvoxamine (an agonist of the S1R, BD + F group) for 4 weeks. The heart rate variability (HRV) and atrial electrophysiological parameters were measured via the PowerLab system and analyzed by LabChart 8.0 software. Atrial histology was determined with Masson staining. The protein levels of connexin (Cx) 40, Cav1.2, S1R, eNOS, p-eNOS, and p-AKT were detected by western blot assays. KEY FINDINGS: Our results showed that BD1047 significantly shortened the atrial effective refractory period (ERP) and action potential duration (APD), increased AF inducibility and duration, augmented sympathetic activity, depressed parasympathetic activity, and reduced heart rate variability (HRV) compared with the CTL group. Masson staining also showed a significant increase in atrial fibrosis in the BD group. Furthermore, the expressions of S1R, Cx40, Cav1.2, p-eNOS, and p-AKT were dramatically reduced in the BD group compared with the CTL group (all P < 0.01). However, fluvoxamine administration mitigated most of the abovementioned alterations. SIGNIFICANCE: Our findings indicated that S1R inhibition contributed to atrial electrical remodeling, cardiac autonomic remodeling and atrial fibrosis, which could be attenuated by fluvoxamine, thus providing new insights into the relationship between the S1R and AF.


Assuntos
Fibrilação Atrial/fisiopatologia , Remodelamento Atrial/fisiologia , Receptores sigma/antagonistas & inibidores , Receptores sigma/fisiologia , Potenciais de Ação , Animais , Fibrilação Atrial/patologia , Canais de Cálcio Tipo L , Conexinas/metabolismo , Etilenodiaminas/farmacologia , Fluvoxamina/farmacologia , Átrios do Coração/efeitos dos fármacos , Átrios do Coração/metabolismo , Átrios do Coração/patologia , Frequência Cardíaca/efeitos dos fármacos , Masculino , Óxido Nítrico Sintase Tipo III/metabolismo , Proteína Oncogênica v-akt/metabolismo , Ratos , Receptores sigma/agonistas , Receptores sigma/metabolismo
12.
Adv Exp Med Biol ; 1143: 1-39, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31338813

RESUMO

Hematopoietic stem cells (HSCs) and leukemic stem cells (LSCs) utilize many of the same signaling pathways for their maintenance and survival. In this review, we will focus on several signaling pathways whose roles have been extensively studied in both HSCs and LSCs. Our main focus will be on the PI3K/AKT/mTOR pathway and several of its regulators and downstream effectors. We will also discuss several other signaling pathways of particular importance in LSCs, including the WNT/ß-catenin pathway, the NOTCH pathway, and the TGFß pathway. For each of these pathways, we will emphasize differences in how these pathways operate in LSCs, compared to their function in HSCs, to highlight opportunities for the specific therapeutic targeting of LSCs. We will also highlight areas of crosstalk between multiple signaling pathways that may affect LSC function.


Assuntos
Células-Tronco Hematopoéticas , Células-Tronco Neoplásicas , Transdução de Sinais , Células-Tronco Hematopoéticas/fisiologia , Humanos , Células-Tronco Neoplásicas/fisiologia , Proteína Oncogênica v-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Serina-Treonina Quinases TOR/metabolismo
13.
Oxid Med Cell Longev ; 2019: 7283683, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31308876

RESUMO

Antioxidative stress provides a cardioprotective effect during myocardial ischemia/reperfusion (I/R). Previous research has demonstrated that the blockade of transient receptor potential vanilloid 4 (TRPV4) attenuates myocardial I/R injury. However, the underlying mechanism remains unclear. The current study is aimed at investigating the antioxidative activity of TRPV4 inhibition and elucidating the underlying mechanisms in vitro and ex vivo. We found that the inhibiting TRPV4 by the selective TRPV4 blocker HC-067047 or specific TRPV4-siRNA significantly reduces reactive oxygen species (ROS) and methane dicarboxylic aldehyde (MDA) levels in H9C2 cells exposed to hypoxia/reoxygenation (H/R). Meanwhile, the activity of antioxidative enzymes, particularly superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), is enhanced. Furthermore, after H/R, HC-067047 treatment increases the expression of P-Akt and the translocation of nuclear factor E2-related factor 2 (Nrf2) and related antioxidant response element (ARE) mainly including SOD, GSH-Px, and catalase (CAT). LY294002, an Akt inhibitor, suppresses HC-067047 and specific TRPV4-siRNA-induced Nrf2 expression and its nuclear accumulation. Nrf2 siRNA attenuates HC-067047 and specific TRPV4-siRNA-induced ARE expression. In addition, treatment with LY294002 or Nrf2 siRNA significantly attenuates the antioxidant and anti-injury effects of HC-067047 in vitro. Finally, in experiments on isolated rat hearts, we confirmed the antioxidative stress roles of TRPV4 inhibition during myocardial I/R and the application of exogenous H2O2. In conclusion, the inhibition of TRPV4 exerts cardioprotective effects through enhancing antioxidative enzyme activity and expressions via the Akt/Nrf2/ARE pathway.


Assuntos
Antioxidantes/metabolismo , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Traumatismo por Reperfusão Miocárdica/metabolismo , Canais de Cátion TRPV/antagonistas & inibidores , Canais de Cátion TRPV/metabolismo , Animais , Elementos de Resposta Antioxidante/efeitos dos fármacos , Elementos de Resposta Antioxidante/genética , Catalase/metabolismo , Cromonas/farmacologia , Peróxido de Hidrogênio/metabolismo , Masculino , Morfolinas/farmacologia , Morfolinas/uso terapêutico , Fator 2 Relacionado a NF-E2 , Proteína Oncogênica v-akt/antagonistas & inibidores , Proteína Oncogênica v-akt/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Pirróis/uso terapêutico , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Superóxido Dismutase/metabolismo
14.
Oxid Med Cell Longev ; 2019: 7609765, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31214282

RESUMO

Background: Saponin from Aralia taibaiensis (sAT) showed excellent antioxidative effects in several models; however, its effects on brain cells were unknown to us. The present study was designed to evaluate the protective effects of sAT on ischemia/reperfusion- (I/R-) induced injury and clarify its mechanisms. Methods: In vitro, HT22 cells were pretreated with sAT and then subjected to I/R. Apoptosis rate, mitochondrial function, and antioxidant proteins were measured. To clarify the mechanisms, siRNA were used. In vivo, sAT was pretreated through intragastric administration for 7 days and the I/R model was induced. The neurobehavioral scores, infarction volumes, and some cytokines in the brain were measured. Protein levels were investigated by Western blotting. Results: The results showed that sAT treatment significantly protected cells from I/R-induced cell apoptosis and mitochondrial dysfunction. The antioxidant protein levels were increased in a dose-dependent manner. Further study revealed that sAT induced the deacetylation and phosphorylation of PGC-1α and FOXO3a. sAT treatment also induced the phosphorylation levels of Akt and the expression levels of SIRT1. Using the specific targeted siRNA transfection, the interplay relationship between Akt, SIRT1, PGC-1α, and FOXO3a was verified. Furthermore, the same protective effects were also observed in rats subjected to I/R. Conclusion: sAT protected brain cells from I/R-induced mitochondrial oxidative stress and dysfunction through regulating the Akt/SIRT1/FOXO3a/PGC-1α pathway.


Assuntos
Araliaceae , Isquemia Encefálica/tratamento farmacológico , Hipocampo/metabolismo , Fármacos Neuroprotetores/uso terapêutico , Traumatismo por Reperfusão/tratamento farmacológico , Saponinas/uso terapêutico , Animais , Linhagem Celular , Modelos Animais de Doenças , Proteína Forkhead Box O3/genética , Proteína Forkhead Box O3/metabolismo , Hipocampo/efeitos dos fármacos , Hipocampo/patologia , Humanos , Infarto da Artéria Cerebral Média , Masculino , Camundongos , Proteína Oncogênica v-akt/genética , Proteína Oncogênica v-akt/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , RNA Interferente Pequeno/genética , Ratos , Ratos Sprague-Dawley , Sirtuína 1/genética , Sirtuína 1/metabolismo
15.
Cells ; 8(5)2019 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-31130711

RESUMO

Nilotinib, a tyrosine kinase inhibitor, has been studied extensively in various tumor models; however, no information exists about the pharmacological action of nilotinib in bacterial infections. Mycobacterium bovis (M. bovis) and Mycobacterium avium subspecies paratuberculosis (MAP) are the etiological agents of bovine tuberculosis and Johne's disease, respectively. Although M. bovis and MAP cause distinct tissue tropism, both of them infect, reside, and replicate in mononuclear phagocytic cells of the infected host. Autophagy is an innate immune defense mechanism for the control of intracellular bacteria, regulated by diverse signaling pathways. Here we demonstrated that nilotinib significantly inhibited the intracellular survival and growth of M. bovis and MAP in macrophages by modulating host immune responses. We showed that nilotinib induced autophagic degradation of intracellular mycobacterium occurred via the inhibition of PI3k/Akt/mTOR axis mediated by abelson (c-ABL) tyrosine kinase. In addition, we observed that nilotinib promoted ubiquitin accumulation around M. bovis through activation of E3 ubiquitin ligase parkin. From in-vivo experiments, we found that nilotinib effectively controlled M. bovis growth and survival through enhanced parkin activity in infected mice. Altogether, our data showed that nilotinib regulates protective innate immune responses against intracellular mycobacterium, both in-vitro and in-vivo, and can be exploited as a novel therapeutic remedy for the control of M. bovis and MAP infections.


Assuntos
Autofagia/efeitos dos fármacos , Mycobacterium avium subsp. paratuberculosis/efeitos dos fármacos , Mycobacterium bovis/efeitos dos fármacos , Paratuberculose/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Pirimidinas/farmacologia , Pirimidinas/uso terapêutico , Tuberculose Bovina/tratamento farmacológico , Animais , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/efeitos dos fármacos , Bovinos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Citoplasma/metabolismo , Citoplasma/microbiologia , Feminino , Imunidade Inata/efeitos dos fármacos , Macrófagos/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Proteína Oncogênica v-akt/metabolismo , Paratuberculose/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Proteínas Quinases/administração & dosagem , Proteínas Proto-Oncogênicas c-abl/metabolismo , Pirimidinas/administração & dosagem , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo , Tuberculose Bovina/metabolismo , Ubiquitina/metabolismo , Ubiquitina-Proteína Ligases/metabolismo
16.
Mar Drugs ; 17(4)2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-30991727

RESUMO

Marine sponges are a prolific source of bioactive compounds. In this work, the putative antiangiogenic potential of a series of synthetic precursors of Solomonamide A, a cyclic peptide isolated from a marine sponge, was evaluated. By means of an in vitro screening, based on the inhibitory activity of endothelial tube formation, the compound Solo F-OH was selected for a deeper characterization of its antiangiogenic potential. Our results indicate that Solo F-OH is able to inhibit some key steps of the angiogenic process, including the proliferation, migration, and invasion of endothelial cells, as well as diminish their capability to degrade the extracellular matrix proteins. The antiangiogenic potential of Solo F-OH was confirmed by means of two different in vivo models: the chorioallantoic membrane (CAM) and the zebrafish yolk membrane (ZFYM) assays. The reduction in ERK1/2 and Akt phosphorylation in endothelial cells treated with Solo F-OH denotes that this compound could target the upstream components that are common to both pathways. Taken together, our results show a new and interesting biological activity of Solo F-OH as an inhibitor of the persistent and deregulated angiogenesis that characterizes cancer and other pathologies.


Assuntos
Inibidores da Angiogênese/farmacologia , Peptídeos Cíclicos/farmacologia , Inibidores da Angiogênese/química , Animais , Técnicas de Cultura de Células , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Membrana Corioalantoide , Células Endoteliais/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Estrutura Molecular , Proteína Oncogênica v-akt/metabolismo , Fragmentos de Peptídeos/metabolismo , Peptídeos Cíclicos/química , Transdução de Sinais/efeitos dos fármacos , Peixe-Zebra
17.
Inflammation ; 42(4): 1401-1412, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30945038

RESUMO

Acute lung injury (ALI) is a syndrome characterized by damage to the alveolar-capillary wall, pulmonary edema and recruitment of inflammatory cells. Previous studies have indicated that aquaporin 4 (AQP4) plays a key role in brain edema formation and resolution. However, the role of AQP4 in the development and progression of ALI is not clear and needs to be resolved. In our current study, mouse ALI was induced by intratracheal instillation of lipopolysaccharide (LPS) at a concentration of 30 mg/kg. For the inhibition of AQP4, 200 mg/kg of TGN-020 (Sigma, USA) was administered intraperitoneally every 6 h starting at 30 min before intratracheal instillation of LPS. The results of the present work indicate, for the first time, that mice treated with the AQP4 inhibitor TGN-020 had attenuated LPS-induced lung injury, reduced proinflammatory cytokine release (including IL-1α, IL-1ß, IL-6, TNF-α, IL-23, and IL-17A), and an improved survival rate. Additionally, we found that the attenuated lung injury scores, increased survival rate, and decreased BALF total protein concentration in TGN-020-treated mice were all abrogated by rIL-17A administration. Furthermore, TGN-020 treatment downregulated the phosphorylation of PI3K and Akt, increased the expression of SOCS3, and decreased the expression of p-STAT3 and RORγt. In conclusion, inhibition of AQP4 by TGN-020 has a detectable protective effect against lung tissue injury induced by LPS, and this effect is associated with inhibition of IL-17A through the downregulation of the PI3K/Akt signaling pathway and upregulation of SOCS3 protein.


Assuntos
Lesão Pulmonar Aguda/prevenção & controle , Aquaporina 4/antagonistas & inibidores , Proliferação de Células/efeitos dos fármacos , Interleucina-17/antagonistas & inibidores , Células Th17/efeitos dos fármacos , Animais , Lipopolissacarídeos/farmacologia , Camundongos , Niacinamida/análogos & derivados , Niacinamida/farmacologia , Proteína Oncogênica v-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Supressoras da Sinalização de Citocina/metabolismo , Células Th17/citologia , Tiadiazóis/farmacologia
18.
Mar Drugs ; 17(4)2019 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-31022939

RESUMO

Vasculogenic mimicry (VM) formed by tumor cells plays a vital role in the progress of tumor, because it provides nutrition for tumor cells and takes away the metabolites. Therefore, the inhibition of VM is crucial to the clinical treatment of tumors. In this study, we investigated the anti-tumor effect of a novel peptide, KVEPQDPSEW (AATP), isolated from abalone (Haliotis discus hannai) on HT1080 cells by migration, invasion analysis and the mode of action. The results showed that AATP effectively inhibited MMPs by blocking MAPKs and NF-κB pathways, leading to the downregulation of metastasis of tumor cells. Moreover, AATP significantly inhibited VM and pro-angiogenic factors, including VEGF and MMPs by suppression of AKT/mTOR signaling. In addition, molecular docking was used to study the interaction of AATP and HIF-1α, and the results showed that AATP was combined with an active site of HIF-1α by a hydrogen bond. The effect of AATP on anti-metastatic and anti-vascular in HT1080 cells revealed that AATP may be a potential lead compound for treatment of tumors in the future.


Assuntos
Inibidores da Angiogênese/farmacologia , Antineoplásicos/farmacologia , Gastrópodes/química , Neoplasias/tratamento farmacológico , Peptídeos/farmacologia , Adulto , Inibidores da Angiogênese/química , Animais , Antineoplásicos/química , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Metaloproteinases da Matriz/metabolismo , NF-kappa B/metabolismo , Metástase Neoplásica , Neoplasias/irrigação sanguínea , Neoplasias/metabolismo , Neoplasias/patologia , Proteína Oncogênica v-akt/metabolismo , Peptídeos/química , Peptídeos/isolamento & purificação , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo , Esferoides Celulares/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , eIF-2 Quinase/metabolismo
19.
Med Sci Monit ; 25: 2238-2245, 2019 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-30914630

RESUMO

Bacterial meningitis has a high mortality rate and can be challenging to diagnose and manage. This study aimed to evaluate the effect of diosmetin in a rat model of Streptococcus pneumoniae meningitis and to investigate the mechanism of action. Forty rats included a treatment group (n=30) that underwent intracisternal injection with S. pneumoniae, and a sham group (n=10) that underwent intracisternal injection with normal saline. In the treatment group, four days before the inoculation of the bacteria, rats were pre-treated with oral diosmetin 100 mg/kg (n=10) and 200 mg/kg (n=10), and the negative control was pre-treated with normal saline (n=10). Bacterial meningitis was confirmed one day after inoculation by cerebrospinal fluid (CSF) bacterial titer and neurological score. In rat brain tissue, levels of inflammatory mediators were determined by enzyme-linked immunosorbent assay (ELISA) and western blot for protein kinase B (Akt), phosphoinositide 3-kinase (PI3K), myeloid differentiation primary response 88 (MyD88), and nuclear factor-kappaB (NF-kappaB), and the TUNEL assay for apoptosis was performed. In the diosmetin-treated group compared with negative control group, the CSF bacterial titer and the level of pro-inflammatory mediators, and the neurological score, were significantly reduced (p<0.01). In the rat hippocampal tissue, levels of Akt, PI3K, MyD88 and NF-kappaB, and the number of TUNEL-positive apoptotic cells were significantly reduced in the diosmetin-treated group compared with negative control group (p<0.01). In a rat model of bacterial meningitis due to S. pneumoniae, diosmetin reduced neuroinflammation, and neuronal apoptosis by modulating the PI3K/AKT/NF-kappaB signaling pathway.


Assuntos
Flavonoides/farmacologia , Meningite Pneumocócica/tratamento farmacológico , Meningite Pneumocócica/metabolismo , Animais , Apoptose/efeitos dos fármacos , China , Citocinas/metabolismo , Modelos Animais de Doenças , Feminino , Flavonoides/metabolismo , Hipocampo/metabolismo , Inflamação/metabolismo , NF-kappa B/efeitos dos fármacos , NF-kappa B/metabolismo , Neurônios/efeitos dos fármacos , Proteína Oncogênica v-akt/efeitos dos fármacos , Proteína Oncogênica v-akt/metabolismo , Fosfatidilinositol 3-Quinases/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Ratos , Ratos Wistar , Transdução de Sinais/efeitos dos fármacos
20.
Immunobiology ; 224(3): 388-396, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30846331

RESUMO

BACKGROUND: We recently identified a novel alternatively spliced isoform of human programmed cell death 1 (PD-1), named Δ42PD1, which contains a 42-base-pair in-frame deletion compared with the full-length PD-1. Δ42PD1 is likely constitutively expressed on human monocytes and down-regulated in patients infected with human immunodeficiency virus type 1 (HIV-1). The mechanism underlying the regulation of Δ42PD-1 expression in monocytes remains unknown. METHODS: By flow cytometry, we investigated the effect of Interferon-gamma (INF-γ) on the expression of Δ42PD1 in primary human monocytes as well as monocytic cell lines THP-1 and U937 cells. In addition, signaling pathway inhibitors and Δ42PD1-specific blocking antibody were used to explore the pathway involved in INF-γ-induced Δ42PD1 upregulation, and to elucidate the relationship between Δ42PD1 and TNF-α or IL-6 production by INF-γ primed monocytes in response to pre-fixed E. coli. Furthermore, we assessed T-cell proliferation, activation and cytokine production as enriched CD4+ T cells were co-cultured with THP-1 or U937 cells, with or without Δ42PD1-blocking antibody. RESULTS: Treatment of human peripheral blood mononuclear cells (PBMCs) with IFN-γ resulted in an approximately 4-fold increase in the expression of Δ42PD1 on monocytes. Similarly, IFN-γ upregulates Δ42PD1 expression on human monocytic cell lines THP-1 and U937, in a time- and dose-dependent manner. IFN-γ-induced Δ42PD1 upregulation was abolished by JAK inhibitors Ruxolitinib and Tasocitinib, PI3K inhibitor LY294002, and AKT inhibitor MK-2206, respectively, but not by STAT1 inhibitor and MAPK signaling pathway inhibitors. JAK, PI3K-AKT, and MAPK signaling inhibitors abolished effectively the production of TNF-α and IL-6 in INF-γ-primed monocytes in response to pre-fixed E. coli. In contrast, Δ42PD1-specific blocking antibody did not affect the IFN-γ-induced priming effect. Furthermore, the MFI ratio of Δ42PD1 to full-length PD-1 (PD-1 Δ/F ratio) was significantly and positively correlated with TNF-α (P = 0.0289, r = 0.6038) produced by circulating CD14+ monocytes in response to pre-fixed E. coli. Notably, Δ42PD1 blockage significantly inhibited CD4+ T-cells proliferation and cytokine production in the co-culture conditions. CONCLUSIONS: We demonstrated that IFN-γ increases Δ42PD1 expression on human monocytes via activating the PI3K/AKT signaling pathway downstream of JAKs, and that the PD-1 Δ/F ratio is a potential biomarker to predict the functional state of monocytes. Notably, we revealed the Δ42PD1 play a role in T-cell regulation, providing a novel potential approach to manipulate adaptive immune response.


Assuntos
Infecções por HIV/metabolismo , HIV-1/fisiologia , Interferon gama/metabolismo , Monócitos/imunologia , Receptor de Morte Celular Programada 1/genética , Isoformas de Proteínas/genética , Linfócitos T/imunologia , Processamento Alternativo , Anticorpos Bloqueadores/farmacologia , Citometria de Fluxo , Infecções por HIV/genética , Humanos , Janus Quinases/metabolismo , Receptores de Lipopolissacarídeos/metabolismo , Ativação Linfocitária , Proteína Oncogênica v-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Receptor de Morte Celular Programada 1/metabolismo , Isoformas de Proteínas/metabolismo , Transdução de Sinais , Células THP-1 , Células U937 , Regulação para Cima
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