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1.
Mol Cell ; 83(11): 1887-1902.e8, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37244254

RESUMO

Interleukin-1ß (IL-1ß) is a key protein in inflammation and contributes to tumor progression. However, the role of IL-1ß in cancer is ambiguous or even contradictory. Here, we found that upon IL-1ß stimulation, nicotinamide nucleotide transhydrogenase (NNT) in cancer cells is acetylated at lysine (K) 1042 (NNT K1042ac) and thereby induces the mitochondrial translocation of p300/CBP-associated factor (PCAF). This acetylation enhances NNT activity by increasing the binding affinity of NNT for NADP+ and therefore boosts NADPH production, which subsequently sustains sufficient iron-sulfur cluster maintenance and protects tumor cells from ferroptosis. Abrogating NNT K1042ac dramatically attenuates IL-1ß-promoted tumor immune evasion and synergizes with PD-1 blockade. In addition, NNT K1042ac is associated with IL-1ß expression and the prognosis of human gastric cancer. Our findings demonstrate a mechanism of IL-1ß-promoted tumor immune evasion, implicating the therapeutic potential of disrupting the link between IL-1ß and tumor cells by inhibiting NNT acetylation.


Assuntos
NADP Trans-Hidrogenases , Neoplasias , Humanos , NADP Trans-Hidrogenases/genética , NADP Trans-Hidrogenases/metabolismo , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Acetilação , Processamento de Proteína Pós-Traducional , Imunoterapia , Neoplasias/tratamento farmacológico , Neoplasias/genética
2.
Eur J Clin Pharmacol ; 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38926166

RESUMO

OBJECTIVE: To systematically evaluate the efficacy of subcutaneous tocilizumab in the treatment of patients with severe COVID-19 and provide evidence for the rational use of subcutaneous tocilizumab in patients with severe COVID-19. METHODS: This meta-analysis was carried out in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. We searched the Cochrane Library, PubMed, Embase, CNKI, SinoMed, and Wanfang Medical Network electronic databases up to 11 January 2023 to identify relevant studies. To obtain the most recent clinical studies of subcutaneous injection of tocilizumab for the treatment of patients with severe COVID-19, we also searched the preprint platforms medRxiv and ChinaXiv. Furthermore, we searched ClinicalTrials.gov for relevant unpublished studies. The studies were screened based on the PICOS principle. The included studies were classified and evaluated for quality based on research type. The RevMan 5.3 software was used to conduct the meta-analysis, and a descriptive analysis was performed to examine relevant outcome indicators. RESULTS: Five observational studies were obtained, involving a total of 498 patients (240 patients in the subcutaneous injection group and 258 patients in the intravenous injection group). All of the studies were of the highest quality. The meta-analysis of the included studies revealed that the mortality rate of patients who received subcutaneous tocilizumab to treat COVID-19 was not significantly higher than that of the intravenous injection group [23.3% (45/193) vs. 18.4% (39/212), RD = 0.06, 95% CI = - 0.01 ~ 0.13, P = 0.11]. Furthermore, there was no significant difference in the proportion of patients requiring mechanical ventilation between the two groups [24.5% (35/143) vs. 22% (35/159), RD = 0.03, 95% CI = - 0.07 ~ 0.12, P = 0.56]. CONCLUSIONS: The meta-analyses do not provide evidence that subcutaneous and intravenous tocilizumab formulations for the treatment of severe COVID-19 infection differ regarding their effectiveness. Considering that the meta-analyses cannot replace an appropriately powered non-inferiority study, subcutaneous formulations still need to be used with caution and only when intravenous formulations are in short supply. At present, there is a lack of randomized controlled trials of subcutaneous injection of tocilizumab for the treatment of severe COVID-19, and more clinical research should be conducted.

3.
Gut ; 72(3): 501-511, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-35803704

RESUMO

OBJECTIVE: Methionine metabolism is involved in a myriad of cellular functions, including methylation reactions and redox maintenance. Nevertheless, it remains unclear whether methionine metabolism, RNA methylation and antitumour immunity are molecularly intertwined. DESIGN: The antitumour immunity effect of methionine-restricted diet (MRD) feeding was assessed in murine models. The mechanisms of methionine and YTH domain-containing family protein 1 (YTHDF1) in tumour immune escape were determined in vitro and in vivo. The synergistic effects of MRD or YTHDF1 depletion with PD-1 blockade were also investigated. RESULTS: We found that dietary methionine restriction reduced tumour growth and enhanced antitumour immunity by increasing the number and cytotoxicity of tumour-infiltrating CD8+ T cells in different mouse models. Mechanistically, the S-adenosylmethionine derived from methionine metabolism promoted the N6-methyladenosine (m6A) methylation and translation of immune checkpoints, including PD-L1 and V-domain Ig suppressor of T cell activation (VISTA), in tumour cells. Furthermore, MRD or m6A-specific binding protein YTHDF1 depletion inhibited tumour growth by restoring the infiltration of CD8+ T cells, and synergised with PD-1 blockade for better tumour control. Clinically, YTHDF1 expression correlated with poor prognosis and immunotherapy outcomes for cancer patients. CONCLUSIONS: Methionine and YTHDF1 play a critical role in anticancer immunity through regulating the functions of T cells. Targeting methionine metabolism or YTHDF1 could be a potential new strategy for cancer immunotherapy.


Assuntos
Metionina , Neoplasias , Camundongos , Animais , Metionina/metabolismo , Linfócitos T CD8-Positivos , Metilação , Receptor de Morte Celular Programada 1 , Racemetionina/metabolismo
4.
Phys Chem Chem Phys ; 25(9): 6857-6866, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36799367

RESUMO

Iridium oxides (iridates) provide a good platform to study the delicate interplay between spin-orbit coupling (SOC) interactions, electron correlation effects, Hund's coupling and lattice degrees of freedom. An overwhelming number of investigations primarily focus on tetravalent (Ir4+, 5d5) and pentavalent (Ir5+, 5d4) iridates, and far less attention has been paid to iridates with other valence states. Here, we pay our attention to a less-explored trivalent (Ir3+, 5d6) iridate, K0.75Na0.25IrO2, crystallizing in a triangular lattice with edge-sharing IrO6 octahedra and alkali metal ion intercalated [IrO2]- layers, offering a good platform to explore the interplay between different degrees of freedom. We theoretically determine the preferred occupied positions of the alkali metal ions from energetic viewpoints and reproduce the experimentally observed semiconducting behavior and nonmagnetic (NM) properties of K0.75Na0.25IrO2. The SOC interactions play a critical role in the band dispersion, resulting in NM Jeff = 0 states. More intriguingly, our electronic structure not only uncovers the presence of intrinsic in-gap states and nearly free electron character for the conduction band minimum, but also explains the abnormally low activation energy in K0.75Na0.25IrO2. Particularly, the band edge can be effectively modulated by mechanical strain, and the in-gap states feature enhanced band-convergence characteristics by 6% compressive strain, which will greatly enhance the electrical conductivity of K0.75Na0.25IrO2. The present work sheds new light on the unconventional electronic structures of trivalent iridates, indicating their promising application as a nanoelectronic and thermoelectric material, which will attract extensive interest and stimulate experimental works to further understand the unprecedented electronic structures and exploit potential applications of the triangular trivalent iridate.

5.
Blood ; 135(3): 208-219, 2020 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-31945154

RESUMO

Mammalian red blood cells lack nuclei. The molecular mechanisms underlying erythroblast nuclear condensation and enucleation, however, remain poorly understood. Here we show that Wdr26, a gene upregulated during terminal erythropoiesis, plays an essential role in regulating nuclear condensation in differentiating erythroblasts. Loss of Wdr26 induces anemia in zebrafish and enucleation defects in mouse erythroblasts because of impaired erythroblast nuclear condensation. As part of the glucose-induced degradation-deficient ubiquitin ligase complex, Wdr26 regulates the ubiquitination and degradation of nuclear proteins, including lamin B. Failure of lamin B degradation blocks nuclear opening formation leading to impaired clearance of nuclear proteins and delayed nuclear condensation. Collectively, our study reveals an unprecedented role of an E3 ubiquitin ligase in regulating nuclear condensation and enucleation during terminal erythropoiesis. Our results provide mechanistic insights into nuclear protein homeostasis and vertebrate red blood cell development.


Assuntos
Diferenciação Celular , Núcleo Celular/metabolismo , Eritroblastos/fisiologia , Eritropoese , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas de Peixe-Zebra/metabolismo , Peixe-Zebra/metabolismo , Animais , Núcleo Celular/genética , Eritroblastos/citologia , Peptídeos e Proteínas de Sinalização Intracelular/genética , Camundongos , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação , Peixe-Zebra/genética , Peixe-Zebra/crescimento & desenvolvimento , Proteínas de Peixe-Zebra/genética
6.
Nature ; 531(7596): 651-5, 2016 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-26982734

RESUMO

CD8(+) T cells have a central role in antitumour immunity, but their activity is suppressed in the tumour microenvironment. Reactivating the cytotoxicity of CD8(+) T cells is of great clinical interest in cancer immunotherapy. Here we report a new mechanism by which the antitumour response of mouse CD8(+) T cells can be potentiated by modulating cholesterol metabolism. Inhibiting cholesterol esterification in T cells by genetic ablation or pharmacological inhibition of ACAT1, a key cholesterol esterification enzyme, led to potentiated effector function and enhanced proliferation of CD8(+) but not CD4(+) T cells. This is due to the increase in the plasma membrane cholesterol level of CD8(+) T cells, which causes enhanced T-cell receptor clustering and signalling as well as more efficient formation of the immunological synapse. ACAT1-deficient CD8(+) T cells were better than wild-type CD8(+) T cells at controlling melanoma growth and metastasis in mice. We used the ACAT inhibitor avasimibe, which was previously tested in clinical trials for treating atherosclerosis and showed a good human safety profile, to treat melanoma in mice and observed a good antitumour effect. A combined therapy of avasimibe plus an anti-PD-1 antibody showed better efficacy than monotherapies in controlling tumour progression. ACAT1, an established target for atherosclerosis, is therefore also a potential target for cancer immunotherapy.


Assuntos
Acetatos/farmacologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Colesterol/metabolismo , Imunoterapia/métodos , Melanoma/tratamento farmacológico , Melanoma/imunologia , Ácidos Sulfônicos/farmacologia , Acetamidas , Acetatos/uso terapêutico , Acetil-CoA C-Acetiltransferase/antagonistas & inibidores , Acetil-CoA C-Acetiltransferase/deficiência , Acetil-CoA C-Acetiltransferase/genética , Acetil-CoA C-Acetiltransferase/metabolismo , Animais , Aterosclerose/tratamento farmacológico , Linfócitos T CD8-Positivos/metabolismo , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Esterificação/efeitos dos fármacos , Feminino , Sinapses Imunológicas/efeitos dos fármacos , Sinapses Imunológicas/imunologia , Sinapses Imunológicas/metabolismo , Masculino , Melanoma/metabolismo , Melanoma/patologia , Camundongos , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Receptor de Morte Celular Programada 1/imunologia , Receptores de Antígenos de Linfócitos T/imunologia , Receptores de Antígenos de Linfócitos T/metabolismo , Transdução de Sinais/efeitos dos fármacos , Sulfonamidas , Ácidos Sulfônicos/uso terapêutico
7.
J Nanobiotechnology ; 20(1): 318, 2022 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-35794597

RESUMO

Cerebral malaria (CM) is a life-threatening neurological complication caused by Plasmodium falciparum. About 627,000 patients died of malaria in 2020. Currently, artemisinin and its derivatives are the front-line drugs used for the treatment of cerebral malaria. However, they cannot target the brain, which decreases their effectiveness. Therefore, increasing their ability to target the brain by the nano-delivery system with brain-targeted materials is of great significance for enhancing the effects of antimalarials and reducing CM mortality. This study used glucose transporter 1 (GLUT1) on the blood-brain barrier as a target for a synthesized cholesterol-undecanoic acid-glucose conjugate. The molecular dynamics simulation found that the structural fragment of glucose in the conjugate faced the outside the phospholipid bilayers, which was conducive to the recognition of brain-targeted liposomes by GLUT1. The fluorescence intensity of the brain-targeted liposomes (na-ATS/TMP@lipoBX) in the mouse brain was significantly higher than that of the non-targeted liposomes (na-ATS/TMP@lipo) in vivo (P < 0.001) after intranasal administration. The infection and recurrence rate of the mice receiving na-ATS/TMP@lipoBX treatment were significantly decreased, which had more advantages than those of other administration groups. The analysis of pharmacokinetic data showed that na-ATS/TMP@lipoBX could enter the brain in both systemic circulation and nasal-brain pathway to treat malaria. Taken together, these results in this study provide a new approach to the treatment of cerebral malaria.


Assuntos
Malária Cerebral , Nanocompostos , Animais , Glucose/química , Transportador de Glucose Tipo 1 , Lipossomos/química , Malária Cerebral/tratamento farmacológico , Camundongos
8.
Sensors (Basel) ; 22(3)2022 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-35162008

RESUMO

Wave attenuation is a widespread physical phenomenon in most acoustic tests, but there is a scarcity of quantitative investigations into the influence of wave attenuation on the determination of shear wave travel time in bender element tests. To ascertain this attenuation effect, a series of bender element tests were conducted on clay samples with different lengths under unconfined conditions. The experimental results suggest that the real first peak of the received signal attenuates gradually with the increase of the sample length and even becomes undistinguished when the sample length exceeds a limit. This phenomenon results in misinterpretation of the wave travel time using the time domain method. In this study, the shear wave travel time is misinterpreted when wave travel distance over approximately 80 mm, leading to underestimation of the VS by 17% for the peak-to-peak approach and 10% for the arrival-to-arrival method. Therefore, besides the near field effect and boundary reflection, the wave attenuation effect turned out to be an important factor influencing the determination of VS using the time domain method. Accordingly, it is advisable to predetermine the limit test distance for a specific testing system under conditions, particularly for long distance testing.

9.
J Biochem Mol Toxicol ; 35(4): e22709, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33491285

RESUMO

Myocardial ischemia/reperfusion (I/R) injury is a very frequent cardiovascular disease and one of the leading causes of death. Abundant evidence has shown that long noncoding RNAs (lncRNAs) are crucial players in myocardial I/R injury. LncRNA cardiac hypertrophy-related factor (CHRF) has been revealed as an important modulator in cardiac disease. However, the function of CHRF in myocardial I/R injury is unclear. In our current work, we found that the expression of CHRF was upregulated in myocardial I/R injury models. Suppression of CHRF relieved myocardial I/R injury in vivo. In addition, in vitro silencing of CHRF enhanced cell viability and attenuated lactate dehydrogenase activity (LDH) as well as apoptosis in H9C2 cells treated with hypoxia/reoxygenation injury. Autophagy has been studied to play an important role in myocardial I/R injury. Thus, experiments related to autophagy were done, and the results showed that CHRF knockdown decreased autophagy. For the exploration of the regulatory mechanism, we found that CHRF sequestered and negatively regulated miR-182-5p to release its inhibition on ATG7. Findings from rescue assays revealed that ATG7 overexpression could suppress the effects of CHRF silence on cell viability, LDH level, apoptosis, and autophagy. To sum up, our results suggested that CHRF exacerbated myocardial I/R injury by enhancing autophagy via modulation of the miR-182-5p/ATG7 pathway. Therefore, this competing endogenous RNA axis may be a potential therapeutic biomarker for myocardial I/R injury.


Assuntos
Proteína 7 Relacionada à Autofagia/metabolismo , MicroRNAs/metabolismo , Traumatismo por Reperfusão Miocárdica/metabolismo , RNA Longo não Codificante/metabolismo , Transdução de Sinais , Animais , Masculino , Traumatismo por Reperfusão Miocárdica/patologia , Ratos , Ratos Sprague-Dawley
10.
Adv Exp Med Biol ; 1316: 149-167, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33740249

RESUMO

T cells recognize "foreign" antigens and induce durable humoral and cellular immune responses, which are indispensable for defending pathogens, as well as maintaining the integrity and homeostasis of tissues and organs. T cells are the major immune cell population in the tumor microenvironment which play a critical role in the antitumor immune response and cancer immune surveillance. Defective immune response of tumor-infiltrating T cells is the main cause of cancer immune evasion. The antitumor response of T cells is affected by multiple factors in the tumor microenvironment, including immunosuppressive cells, immune inhibitory cytokines, tumor-derived suppressive signals like PD-L1, immnuogenicity of tumor cells, as well as metabolic factors like hypoxia and nutrient deprivation. Abundant studies in past decades have proved the metabolic regulations of the immune response of T cells and the tumor-infiltrating T cells. In this chapter, we will discuss the regulations of the antitumor response of tumor-infiltrating T cells by lipid metabolism, which is one of the main components of metabolic regulation.


Assuntos
Neoplasias , Linfócitos T , Citocinas/metabolismo , Humanos , Metabolismo dos Lipídeos , Linfócitos do Interstício Tumoral/metabolismo , Linfócitos T/metabolismo , Microambiente Tumoral
11.
J Pathol ; 248(4): 438-451, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30900255

RESUMO

The mineralocorticoid receptor (MR) plays important roles in cardiovascular pathogenesis. The function of MR in angiogenesis is still controversial. This study aimed to explore the role of endothelial MR in angiogenesis and to delineate the underlying mechanism. Endothelial-hematopoietic MR knockout (EMRKO) mice were generated and subjected to hindlimb ischemia and injection of melanoma cells. Laser Doppler measurements showed that EMRKO mice had improved blood flow recovery and increased vessel density in ischemic limbs. In addition, EMRKO accelerated growth and increased the vessel density of tumors. Matrigel implantation, aortic ring assays, and tube formation assays demonstrated that MRKO endothelial cells (ECs) manifested increased angiogenic potential. MRKO ECs also displayed increased migration ability and proliferation. MRKO and MR knockdown both upregulated gene expression, protein level, and phosphorylation of signal transducer and activator of transcription 3 (STAT3). Stattic, a selective STAT3 inhibitor, attenuated the effects of MRKO on tube formation, migration, and proliferation of ECs. At the molecular level, MR interacted with CCAAT enhancer-binding protein beta (C/EBPß) to suppress the transcription of STAT3. Furthermore, interactions between MR and STAT3 blocked the phosphorylation of STAT3. Finally, stattic abolished the pro-angiogenic phenotype of EMRKO mice. Taken together, endothelial MR is a negative regulator of angiogenesis, likely in a ligand-independent manner. Mechanistically, MR downregulates STAT3 that mediates the impacts of MR deficiency on the angiogenic activity of ECs and angiogenesis. Targeting endothelial MR may be a potential pro-angiogenic strategy for ischemic diseases. © 2019 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.


Assuntos
Células Endoteliais/metabolismo , Neovascularização Patológica/metabolismo , Receptores de Mineralocorticoides/metabolismo , Fator de Transcrição STAT3/metabolismo , Animais , Biomarcadores/metabolismo , Movimento Celular , Proliferação de Células , Regulação para Baixo , Células Endoteliais/patologia , Feminino , Masculino , Camundongos , Camundongos Knockout , Neovascularização Patológica/patologia , Neovascularização Patológica/fisiopatologia
12.
J Biol Chem ; 293(3): 1030-1039, 2018 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-29203528

RESUMO

Type I IFN production and signaling in macrophages play critical roles in innate immune responses. High salt (i.e. high concentrations of NaCl) has been proposed to be an important environmental factor that influences immune responses in multiple ways. However, it remains unknown whether high salt regulates type I IFN production and signaling in macrophages. Here, we demonstrated that high salt promoted IFNß production and its signaling in both human and mouse macrophages, and consequentially primed macrophages for strengthened immune sensing and signaling when challenged with viruses or viral nucleic acid analogues. Using both pharmacological inhibitors and RNA interference we showed that these effects of high salt on IFNß signaling were mediated by the p38 MAPK/ATF2/AP1 signaling pathway. Consistently, high salt increased resistance to vesicle stomatitis virus (VSV) infection in vitro. In vivo data indicated that a high-salt diet protected mice from lethal VSV infection. Taken together, these results identify high salt as a crucial regulator of type I IFN production and signaling, shedding important new light on the regulation of innate immune responses.


Assuntos
Interferon Tipo I/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Cloreto de Sódio/farmacologia , Animais , Antivirais/farmacologia , Western Blotting , Farmacorresistência Viral , Humanos , Imunidade Inata , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Transdução de Sinais/efeitos dos fármacos , Proteínas Quinases p38 Ativadas por Mitógeno/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
13.
Circ Res ; 120(10): 1584-1597, 2017 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-28298295

RESUMO

RATIONALE: Hypertension remains to be a global public health burden and demands novel intervention strategies such as targeting T cells and T-cell-derived cytokines. Mineralocorticoid receptor (MR) antagonists have been clinically used to treat hypertension. However, the function of T-cell MR in blood pressure (BP) regulation has not been elucidated. OBJECTIVE: We aim to determine the role of T-cell MR in BP regulation and to explore the mechanism. METHODS AND RESULTS: Using T-cell MR knockout mouse in combination with angiotensin II-induced hypertensive mouse model, we demonstrated that MR deficiency in T cells strikingly decreased both systolic and diastolic BP and attenuated renal and vascular damage. Flow cytometric analysis showed that T-cell MR knockout mitigated angiotensin II-induced accumulation of interferon-gamma (IFN-γ)-producing T cells, particularly CD8+ population, in both kidneys and aortas. Similarly, eplerenone attenuated angiotensin II-induced elevation of BP and accumulation of IFN-γ-producing T cells in wild-type mice. In cultured CD8+ T cells, T-cell MR knockout suppressed IFN-γ expression whereas T-cell MR overexpression and aldosterone both enhanced IFN-γ expression. At the molecular level, MR interacted with NFAT1 (nuclear factor of activated T-cells 1) and activator protein-1 in T cells. Finally, T-cell MR overexpressing mice manifested more elevated BP compared with control mice after angiotensin II infusion and such difference was abolished by IFN-γ-neutralizing antibodies. CONCLUSIONS: MR may interact with NFAT1 and activator protein-1 to control IFN-γ in T cells and to regulate target organ damage and ultimately BP. Targeting MR in T cells specifically may be an effective novel approach for hypertension treatment.


Assuntos
Pressão Sanguínea/fisiologia , Interferon gama/fisiologia , Receptores de Mineralocorticoides/fisiologia , Linfócitos T/fisiologia , Acetilcolina/farmacologia , Animais , Pressão Sanguínea/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Hipertensão/genética , Hipertensão/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout
14.
J Biol Chem ; 292(3): 925-935, 2017 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-27881672

RESUMO

Mineralocorticoid receptor (MR) has been considered as a potential target for treating atherosclerosis. However, the cellular and molecular mechanisms are not completely understood. We aim to explore the functions and mechanisms of macrophage MR in atherosclerosis. Atherosclerosis-susceptible LDLRKO chimeric mice with bone marrow cells from floxed control mice or from myeloid MR knock-out (MRKO) mice were generated and fed with high cholesterol diet. Oil red O staining showed that MRKO decreased atherosclerotic lesion area in LDLRKO mice. In another mouse model of atherosclerosis, MRKO/APOEKO mice and floxed control/APOEKO mice were generated and treated with angiotensin II. Similarly, MRKO inhibited the atherosclerotic lesion area in APOEKO mice. Histological analysis showed that MRKO increased collagen coverage and decreased necrosis and macrophage accumulation in the lesions. In vitro results demonstrated that MRKO suppressed macrophage foam cell formation and up-regulated the expression of genes involved in cholesterol efflux. Furthermore, MRKO decreased accumulation of apoptotic cells and increased effective efferocytosis in atherosclerotic lesions. In vitro study further revealed that MRKO increased the phagocytic index of macrophages without affecting their apoptosis. In conclusion, MRKO reduces high cholesterol- or angiotensin II-induced atherosclerosis and favorably changes plaque composition, likely improving plaque stability. Mechanistically, MR deficiency suppresses macrophage foam cell formation and up-regulates expression of genes related to cholesterol efflux, as well as increases effective efferocytosis and phagocytic capacity of macrophages.


Assuntos
Apoptose , Aterosclerose/metabolismo , Células Espumosas/metabolismo , Receptores de Mineralocorticoides/deficiência , Regulação para Cima , Angiotensina II/efeitos adversos , Angiotensina II/farmacologia , Animais , Aterosclerose/induzido quimicamente , Aterosclerose/genética , Aterosclerose/patologia , Colesterol/efeitos adversos , Colesterol/metabolismo , Colesterol/farmacologia , Modelos Animais de Doenças , Feminino , Células Espumosas/patologia , Masculino , Camundongos , Camundongos Knockout , Receptores de Mineralocorticoides/metabolismo
15.
Acta Biochim Biophys Sin (Shanghai) ; 50(3): 254-262, 2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29385398

RESUMO

Hypoxic-ischemic encephalopathy (HIE) is a complex condition which is associated with high mortality and morbidity. However, few promising treatments for HIE exist. In the present study, the central objective was to identify the therapeutic effect of pilose antler polypeptides (PAP) on HIE in rats. Sprague-Dawley (SD) rats (14 days old) were used and divided into three groups, including control group, hypoxic-ischemia (HI) group and PAP group. After 21 days of treatment, locomotor activity was improved in PAP-treated rats, brain atrophy was decreased and cerebral edema was mitigated to some extent. Real-time quantitative polymerase chain reaction (RT-qPCR) analysis indicated that PAP administration decreased the expressions of inflammatory cytokines and apoptosis genes in hippocampus compared with HI group. Furthermore, the mRNA expressions of genes related to neurotrophic factors were significantly increased in the hippocampus. In addition, the expressions of oxidative stress markers were all down-regulated after PAP administration. Moreover, PAP up-regulated both the mRNA and protein levels of SDF1 and CXCR4, which may activate the SDF1/CXCR4 axis to moderate brain injury. These results suggest that PAP may be potentially used in the treatment of HIE.


Assuntos
Chifres de Veado/metabolismo , Quimiocina CXCL12/metabolismo , Hipóxia-Isquemia Encefálica/prevenção & controle , Fatores de Crescimento Neural/metabolismo , Peptídeos/farmacologia , Receptores CXCR4/metabolismo , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Quimiocina CXCL12/genética , Citocinas/genética , Citocinas/metabolismo , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Hipóxia-Isquemia Encefálica/genética , Hipóxia-Isquemia Encefálica/metabolismo , Masculino , Atividade Motora/efeitos dos fármacos , Fatores de Crescimento Neural/genética , Ratos Sprague-Dawley , Receptores CXCR4/genética
16.
Zhongguo Zhong Yao Za Zhi ; 43(15): 3051-3057, 2018 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-30200698

RESUMO

Cerebral malaria (CM) is the leading cause of death in children under 5 years in Africa, severe neurological sequelae may occur in surviving children. Although artesunate has made breakthrough progress in the clinical treatment of CM, the clinical problems of high mortality and high morbidity have not yet been completely resolved. In this study, an experimental cerebral malaria (ECM) model was established by infecting C57BL/6 mice with Pb ANKA (Plasmodium berghei ANKA) to compare parasitemia level, survival rates, and rapid murine coma behavior scale scores, cerebral microvascular obstruction, haemozoin deposition in the liver, body temperature and weight to investigate the anti-cerebral malaria effect of the artesunate compound combination. The results showed that the artesunate compound combination could improve the survival rate of Pb ANKA-infected mice, reduce the level of parasitemia, effectively improve the symptoms of ECM neurological injury, reduce cerebrovascular obstruction and haemozoin deposition in the liver, and also significantly improve body temperature, weight and other basic indicators. The results showed that the artesunate compound combination improved the pathological changes and neurological damage caused by CM. It is expected to provide a theoretical basis for human cerebral malaria patients in clinical adjuvant therapy.


Assuntos
Antimaláricos/farmacologia , Artesunato/farmacologia , Malária Cerebral/tratamento farmacológico , Animais , Modelos Animais de Doenças , Camundongos , Camundongos Endogâmicos C57BL , Plasmodium berghei
17.
Zhongguo Zhong Yao Za Zhi ; 43(16): 3397-3403, 2018 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-30200747

RESUMO

Malaria is still the most severe strain of the human malaria parasites, and malaria disease is life-threatening which can result in severe anemia and cerebral malaria, especially in children in tropical Africa. Previous studies have shown that artemisinin and its derivatives could selectively kill erythrocytic stage of malaria and have a greater impact on the ring period. In recent years, there have been new findings of its mechanism continually. However, the concentration of artemisinin and its derivatives used in these studies can reach 50 to 80 times the half-inhibitory concentration in vitro. In this study, the international standard strain 3D7 of Plasmodium falciparum was used to culture in vitro. After half-inhibitory concentration of dihydroartemisinin was treated, the morphological changes of P. falciparum intraerythrocytic stage were observed, and then the 3D7 life cycle and effects of different developmental stages after dosing was explored. The 3D7 strain of P. falciparum was continuously synchronised more than 3 times. And dihydroartemisinin (DHA) at half maximal inhibitory concentration (10 nmol·L⁻¹) was administered for 6 hours after the last synchronization, and 3 life cycles were continuously observed (132 h). The results showed that compared with the parasites untreated by DHA, there was a noticeable delay in the life cycle of at least 36 h, indicating that the growth of 3D7 was significantly inhibited by DHA (P<0.001), and the rate of ring formation was significantly reduced (P<0.05). The trophozoites were abnormal in shape, such as shrink in size, and the number of merozoites in schizonts was significantly decreased (P<0.05). These results suggested that non-killing concentrations of DHA (meaning parasites can be inhibited but not killed) can significantly inhibit the growth of P. falciparum, which may not only affect the ring stage, but also have an impact on other stages of the P. falciparum.


Assuntos
Antimaláricos/farmacologia , Artemisininas/farmacologia , Plasmodium falciparum/efeitos dos fármacos , Humanos
18.
Circ Res ; 117(4): 364-375, 2015 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-26123998

RESUMO

RATIONALE: Wnt/ß-catenin signaling has an important role in the angiogenic activity of endothelial cells (ECs). Bach1 is a transcription factor and is expressed in ECs, but whether Bach1 regulates angiogenesis is unknown. OBJECTIVE: This study evaluated the role of Bach1 in angiogenesis and Wnt/ß-catenin signaling. METHODS AND RESULTS: Hind-limb ischemia was surgically induced in Bach1(-/-) mice and their wild-type littermates and in C57BL/6J mice treated with adenoviruses coding for Bach1 or GFP. Lack of Bach1 expression was associated with significant increases in perfusion and vascular density and in the expression of proangiogenic cytokines in the ischemic hindlimb of mice, with enhancement of the angiogenic activity of ECs (eg, tube formation, migration, and proliferation). Bach1 overexpression impaired angiogenesis in mice with hind-limb ischemia and inhibited Wnt3a-stimulated angiogenic response and the expression of Wnt/ß-catenin target genes, such as interleukin-8 and vascular endothelial growth factor, in human umbilical vein ECs. Interleukin-8 and vascular endothelial growth factor were responsible for the antiangiogenic response of Bach1. Immunoprecipitation and GST pull-down assessments indicated that Bach1 binds directly to TCF4 and reduces the interaction of ß-catenin with TCF4. Bach1 overexpression reduces the interaction between p300/CBP and ß-catenin, as well as ß-catenin acetylation, and chromatin immunoprecipitation experiments confirmed that Bach1 occupies the TCF4-binding site of the interleukin-8 promoter and recruits histone deacetylase 1 to the interleukin-8 promoter in human umbilical vein ECs. CONCLUSIONS: Bach1 suppresses angiogenesis after ischemic injury and impairs Wnt/ß-catenin signaling by disrupting the interaction between ß-catenin and TCF4 and by recruiting histone deacetylase 1 to the promoter of TCF4-targeted genes.


Assuntos
Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Células Endoteliais/metabolismo , Proteínas de Grupos de Complementação da Anemia de Fanconi/metabolismo , Isquemia/metabolismo , Músculo Esquelético/irrigação sanguínea , Neovascularização Fisiológica , Via de Sinalização Wnt , beta Catenina/metabolismo , Acetilação , Animais , Apoptose , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Fatores de Transcrição de Zíper de Leucina Básica/deficiência , Fatores de Transcrição de Zíper de Leucina Básica/genética , Sítios de Ligação , Movimento Celular , Proliferação de Células , Modelos Animais de Doenças , Regulação para Baixo , Proteínas de Grupos de Complementação da Anemia de Fanconi/genética , Feminino , Células HEK293 , Membro Posterior , Histona Desacetilase 1/genética , Histona Desacetilase 1/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Interleucina-8/genética , Interleucina-8/metabolismo , Isquemia/genética , Isquemia/fisiopatologia , Masculino , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Nus , Regiões Promotoras Genéticas , Ligação Proteica , Interferência de RNA , Fator de Transcrição 4 , Fatores de Transcrição/metabolismo , Transfecção , Fator A de Crescimento do Endotélio Vascular/metabolismo , Proteína Wnt3A/metabolismo , beta Catenina/genética , Fatores de Transcrição de p300-CBP/metabolismo
19.
Bioorg Med Chem ; 25(16): 4384-4396, 2017 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-28651913

RESUMO

Highly pathogenic H5N1 virus (H5N1) entry is a key target for the development of novel anti-influenza agents with new mechanisms of action. In our continuing efforts to identify novel potential anti-H5N1 entry inhibitors, a series of 3-O-ß-chacotriosyl oleanolic acid analogs have been designed, synthesized and evaluated as H5N1 entry inhibitors based on two small molecule inhibitors 1 and 2 previously discovered by us. The anti-H5N1 entry activities were determined based on HA/HIV and VSVG/HIV entry assays. Compound 15 displayed the most promising anti-H5N1 entry activities with average IC50 values of 4.05µM and good selective index (22.9). Detailed structure-activity relationships (SARs) studies suggested that either the introduction of an additional oxo group to position 11 at OA or alteration of the C-3 configuration of OA from 3ß- to 3α-forms can significantly enhance the selective index while maintaining their antiviral activities in vitro. Molecular simulation analysis confirmed that the compounds exert their inhibitory activity through binding tightly to hemagglutinin (HA2) protein near the fusion peptide and prevent virus entry.


Assuntos
Antivirais/farmacologia , Virus da Influenza A Subtipo H5N1/efeitos dos fármacos , Ácido Oleanólico/farmacologia , Animais , Antivirais/síntese química , Antivirais/química , Cães , Relação Dose-Resposta a Droga , Células Madin Darby de Rim Canino/efeitos dos fármacos , Células Madin Darby de Rim Canino/virologia , Testes de Sensibilidade Microbiana , Estrutura Molecular , Ácido Oleanólico/síntese química , Ácido Oleanólico/química , Relação Estrutura-Atividade
20.
Zhongguo Zhong Yao Za Zhi ; 42(5): 951-957, 2017 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-28994540

RESUMO

Shuyu Yiban decoction(SYYB) has significant effect in treating the patients with coronary heart disease combined with chronic psychological stress. In this study, in order to observe the effects of SYYB on early formation of atherosclerosis(As) and inflammation response induced by chronic psychological stress, high-fat diet+intraperitoneal injections of Vitamin D3 were given to establish As early lesion models, and based on these models, chronic unpredictable mild stress(CUMS) was used to observe whether the chronic psychological stress could increase coronary atherosclerotic lesions investigate the intervention effect of SYYB(6.6, 13.2, 26.4 mg•kg⁻¹). The tail suspension test and novelty-feeding test were adopted to detectadrenocortico-tropic hormone(ACTH), cortisol(Cor) andnoradrenaline(NE) in serum and weigh thymus and adrenal gland, in order to assess the effects of SYYB on CUMS model rats. The pathological changes of vascular tissues in aortic arch were observed by using hematoxylin and eosin(HE) staining, and then the levels of triglycerides(TG), total cholesterol(TC) and high density lipoprotein(HDL-C) in serum were determined to assess effects of SYYB on As lesions. The effects of SYYB on the inflammatory response in As rats were assessed by detecting high-sensitivity C-reactive protein(hsCRP), interleukin-1ß(IL-1ß) and interleukin-6(IL-6) in serum. The results showed that as compared with the blank control group, TC and TG levels in As group were increased while HDL-C was markedly decreased; furthermore, the aortic wall was thickened in HE staining. Meanwhile, foam cells were formed, and the behavioral assessment and serum stress hormone test showed that there was a chronic stress response, indicating successful establishment of As+CUMS models in this study. The experiment demonstrated that SYYB could lower the levels of serum TC and TG, reduce foam cells, calcification and inflammatory cells infiltration. Moreover, SYYB could obviously lower levels of ACTH, Cor and NE and the As related inflammatory indicatorhs-CRP, IL-1ß and IL-6 in serum.These results indicated that SYYB had protective effect on chronic psychological stress induced in As rats, and the mechanism was associated with balancing the neuroendocrine-immune network system and regulating inflammation response.


Assuntos
Aterosclerose/tratamento farmacológico , Medicamentos de Ervas Chinesas/farmacologia , Estresse Psicológico , Animais , Proteína C-Reativa/análise , Dieta Hiperlipídica , Inflamação/tratamento farmacológico , Interleucina-1beta/sangue , Interleucina-6/sangue , Ratos
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