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1.
J Phys Condens Matter ; 36(35)2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38806048

RESUMO

Recently, signatures of superconductivity with critical temperature from 20 to 30 K have been reported in pressured trilayer nickelate La4Ni3O10through a pressure-induced structure transition. Here we explore the evolution of electronic structures and electronic correlations in different phases of La4Ni3O10under corresponding pressure regions, by using density functional theory (DFT) combined with dynamical mean-field theory (DMFT). Similar to bilayer superconductor La3Ni2O7, the electronic bands in superconducting La4Ni3O10are dominated by Ni-3dx2-y2and 3dz2orbits near the Fermi level, in contrast, the inner Ni-O plane in La4Ni3O10generates a doublet hole-pocket Fermi surfaces around the Brillouin-zone corner, meanwhile one branch of the Ni-3dz2bands is pushed very close above the Fermi level, which can induce an electron pocket through small electron doping. The DFT+DMFT simulations suggest that the electronic correlations only give minor modification to the Fermi surfaces, meanwhile the Ni-3dz2and 3dx2-y2states on outer Ni-O layers have considerable greater mass enhancements than on the inner layer. The sensitiveness of electronic structure under doping and unique layer dependence of correlation suggest a distinct superconducting mechanism with respect to bilayer La3Ni2O7. Based on the DFT and DFT+DMFT simulations, we eventually derive a trilayer effective tight-binding model, which can produce rather precise electronic bands and Fermi surfaces, hence can serve as an appropriate model to further study the superconducting mechanism and paring symmetry in trilayer La4Ni3O10.

2.
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
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.
Zhen Ci Yan Jiu ; 47(11): 975-82, 2022 Nov 25.
Artigo em Chinês | MEDLINE | ID: mdl-36453674

RESUMO

OBJECTIVE: To observe the effect of electroacupuncture (EA) on the ocular surface inflammation and α7 nicotinic acetylcholine receptor (α7nAChR) / nuclear factor kappa-B (NF-κB) p65 signal pathway in guinea pigs with dry eye, so as to explore its underlying mechanism. METHODS: A total of 32 male British tricolor short haired guinea pigs were randomized into blank control, model, EA and sham acupuncture groups, with 8 guinea pigs in each group. The dry eye model was established by subcutaneous injection of scopolamine hydrobromide solution (0.6 mg/0.2 mL each time, 4 times a day for 10 days). Guinea pigs of the EA group was treated with EA at bilateral "Cuanzhu" (BL2) and "Taiyang" (HN5), and manual acupuncture at bilateral "Jingming" (BL1), "Sizhukong" (SJ23), "Tongziliao" (GB1) for 15 min, once daily for 14 days. For animals of the sham acupuncture group, a blunt needle was used to prick the skin surface of the acupoints, the acupoint selection and stimulation time were the same as those in the EA group. Before and after modeling and after the intervention, the breakup time (BUT) of lacrimal film, sodium fluorescein coloring (Fl) state of corneal epithelium and phenol red thread (PRT) moist length were recorded for assessing the severity of dry eye. The density of activated immune cells around the corneal epithelial stromal cells was determined by corneal confocal microscopy. The contents of interleukin-4 (IL-4), IL-6, IL-10, tumor necrosis factor α (TNF-α) in the cornea and lacri-mal gland tissues were determined by ELISA, and the expression levels of α7nAChR and NF-κB p65 in the cornea and lacrimal gland were detected by immunohistochemistry and Western blot, separately. RESULTS: Compared with the blank control group, the corneal Fl, density of activated immune cells of corneal epithelium, contents of IL-6, IL-10 and TNF-α in both corneal and lacrimal gland tissues, NF-κB p65 cell positive rate and protein expression of lacrimal gland and corneal tissues were significantly increased (P<0.01, P<0.05), while the BUT, PRT and lacrimal gland α7nAChR cell positive rate considerably decreased (P<0.01) in the model group. In comparison with the model group, the level of corneal Fl, density of the activated immune cells of corneal epithelium, contents of corneal and lacrimal IL-6 and TNF-α, and corneal and lacrimal NF-κB p65 cell positive rates and protein expressions were remarkably down-regulated in the EA group (P<0.01, P<0.05), rather than in the sham acupuncture group (P>0.05) except content of corneal IL-10, lacrimal NF-κB p65 cell positive rate and lacrimal α7nAChR protein expression, whereas the levels of BUT, PRT, corneal and lacrimal IL-10 and corneal and lacrimal α7nAChR cell positive rates and protein expressions significantly up-regulated in the EA group (P<0.01, P<0.05), rather than in the sham acupuncture group (P>0.05) except corneal TNF-α and corneal NF-κB p65 protein expression. CONCLUSION: EA can improve corneal and lacrimal function in dry eye guinea pigs, which may be associated with its actions in increasing the expression of α7nAChR, inhibiting the nuclear translocation of NF-κB, and reducing the activated immune cells and inflammatory reaction.


Assuntos
Terapia por Acupuntura , Síndromes do Olho Seco , Aparelho Lacrimal , Masculino , Cobaias , Animais , NF-kappa B/genética , Receptor Nicotínico de Acetilcolina alfa7/genética , Interleucina-10 , Fator de Necrose Tumoral alfa , Interleucina-6 , Síndromes do Olho Seco/genética , Síndromes do Olho Seco/terapia , Transdução de Sinais , Inflamação/genética , Inflamação/terapia
5.
Zhen Ci Yan Jiu ; 47(5): 393-400, 2022 May 25.
Artigo em Chinês | MEDLINE | ID: mdl-35616412

RESUMO

OBJECTIVE: To observe the effect of electroacupuncture (EA) on ocular surface sensory neuralgia and the expression of P2X3 receptor (P2X3R) and protein kinase C(PKC)in cornea and trigeminal ganglion (TG) in dry eye disease (DED) guinea pigs, so as to explore its mechanism underlying improvement of ocular surface sensory neuralgia in DED. METHODS: Male British tricolor short haired guinea pigs were randomly divided into control, model, medication (pranoprofen), EA and sham acupuncture groups, with 8 guinea pigs in each group. The dry eye model was induced by subcutaneous injection of scopolamine hydrobromide solution (0.6 mg/0.2 mL,once daily) for 10 d. Guinea pigs in the medication group were treated by applying pranoprofen eye drops to eyes, 1 drop for one eye each time, three times a day. Guinea pigs of the EA group received EA stimulation (4 Hz/20 Hz,1 mA) of bilateral "Cuanzhu" (BL2) and "Taiyang" (HN5) and acupuncture at "Jingming" (BL1) "Sizhukong" (TE23), "Tongziliao" (GB1) for 15 min, once a day. Guinea pigs in the sham acupuncture group received blunt stimu-lation at the surface of the same acupoint with the tip of the acupuncture needle, once a day. All the treatments were conducted for 14 d. The corneal epithelium fluorescein staining score (0-3 points) was given according to the number of fluorescence-positive dots and flake-like coloration, the corneal mechanical perception thread (CMPT) detected using a corneal perception meter, and the palpebral fissure height measured. The number of sensory neurons in the cornea and TG was determined by using cholera toxin subunit B conjugated with Alexa Fluor 488 fluorescence labelling, and the expression levels of P2X3R and PKC in the cornea and TG detected by using immunohistochemistry and Western blot, separately. RESULTS: Compared with the control group, the corneal fluorescein staining score, immunoactivity and expression of P2X3R proteins in both cornea and TG, PKC proteins in TG were significantly increased (P<0.01), whereas the CMPT and the height of palpebral fissure and the number of TG neurons significantly decreased in the model group (P<0.05,P<0.01). In comparison with the model group, the fluorescein staining score in the medication and EA groups, the immunoactivity and expression of P2X3R in cornea and TG in the EA group, and that of TG PKC in the EA group and the sham acupuncture groups were significantly decreased (P<0.05, P<0.01), while the height of palpebral fissure and CMPT after EA and the number of labelling TG sensory neurons were remarkably increased in the EA group (P<0.01) rather than in the medication and sham acupuncture groups (P>0.05). CONCLUSION: EA can alleviate the damage of corneal epithelium and sensory neurons in dry eye model guinea pigs, which may be related to its functions in down-regu-lating the expression of P2X3R and PKC in the cornea and TG.


Assuntos
Síndromes do Olho Seco , Eletroacupuntura , Neuralgia , Pontos de Acupuntura , Animais , Córnea , Síndromes do Olho Seco/genética , Síndromes do Olho Seco/terapia , Fluoresceínas , Cobaias , Masculino , Ratos , Ratos Sprague-Dawley , Ácidos Sulfônicos , Gânglio Trigeminal
6.
J Chromatogr A ; 1643: 462058, 2021 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-33756356

RESUMO

A reverse micelle mediated dispersive liquid-liquid microextraction (RM-DLLME) combined with high performance liquid chromatography-ultraviolet detector (HPLC-UV) was developed for extraction and determination of 5 A2 components of teicoplanin (TA2-1, TA2-2, TA2-3, TA2-4, TA2-5) in human plasma, and the mechanism of RM-DLLME was analysed and explored. In this method, 80 µL of the reverse micelle solution of cetylpyridinium chloride/n-hexanol (15 mmol/L) was used as the extraction solvent for the separation, extraction and enrichment of the teicoplanin in plasma sample. All factors affecting the extraction efficiencies of the target analytes, such as the amounts of acetonitrile and chloroform, the type and volume of reverse micelle solution, pH and volume of sample phase, dispersant, salt addition, extraction mode and time, centrifugation rate and time, were investigated and optimized. Under the optimum conditions, the 5 A2 components of teicoplanin achieved effective enrichment with the enrichment factors of 228-347 and obtained good linearity in the range of 0.8375-100.5 µg/mL with correlation coefficients higher than 0.9960. The limits of detection were ranged between 0.5025-3.015 µg/mL. Relative standard deviation values of the method precisions were lower than 10.6% and the average recoveries were in the range of 82.7-111.3%. The determination results of the method were demonstrated with favorable characteristics, such as high enrichment, good selectivity and sensitivity, satisfactory precision and accuracy, and this method could be employed to analysis of the teicoplanin in human plasma samples.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Microextração em Fase Líquida/métodos , Micelas , Teicoplanina/sangue , Humanos , Concentração de Íons de Hidrogênio , Limite de Detecção , Reprodutibilidade dos Testes , Espectrofotometria Ultravioleta , Teicoplanina/química , Teicoplanina/isolamento & purificação
7.
J Phys Condens Matter ; 33(2): 025601, 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-32906113

RESUMO

Using the constrained-path quantum Monte Carlo method, we systematically study the half-filled Hubbard model on AA-stacked honeycomb lattice. Our simulations demonstrate that a dominant chiral d + id wave superconductivity can be induced by a perpendicular electric field. At a fixed electric field, the effective pairing interaction of chiral d + id superconductivity exhibits an increasing behavior with increasing the on-site Coulomb interaction. We attribute the electric field-induced d + id superconductivity to an increased density of states near the Fermi energy and robust antiferromagnetic spin correlation upon turning on electric field. Our results strongly suggest that the AA-stacked graphene system is a good candidate for chiral d + id superconductor.

8.
ACS Omega ; 5(42): 27374-27382, 2020 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-33134700

RESUMO

In this study, the natural zeolite and rice husk biochar were mixed as a combination amendment for metal immobilization in a Cd, Pb, As, and W co-contaminated soil. A 90 day incubation study was conducted to investigate the effects of amendments on toxic metal in soil. Zeolite, biochar, and their combination application increased the soil pH and cation exchange capacity. A combination of amendments decreased the bioavailability of Cd, Pb, As, and W. Besides, the potential drawback of biochar application on As and W release was overcome by the combination agent. Zeolite, biochar, and combination treatment decreased total bioavailability toxicity from 335.5 to 182.9, 250.5, and 143.4, respectively, which means that combination was an optimum amendment for soil remediation. The results of the Community Bureau of Reference sequential extraction and scanning electron microscopy-energy-dispersive spectrometry images confirmed the Cd and Pb adsorption onto biochar. However, As and W immobilization was dominantly controlled by zeolite. It appears that the combination of amendments is an efficient amendment to remediate Cd, Pb, As, and W co-contamination in soil, although the combination of amendments has a lower stabilization rate for W than for zeolite.

9.
Front Pharmacol ; 11: 134, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32210797

RESUMO

Ischemic heart disease (IHD), caused predominantly by atherosclerosis, is a leading cause of global mortality. Our previous studies showed that Shenlian extract (SL) could prevent the formation of atherosclerosis and enhance the stability of atherosclerotic plaques. To further investigate the protective effects of SL on myocardial ischemic injury and its possible mechanisms, anesthetized dogs, ex vivo rat hearts, and H9c2 cardiomyocytes were used as models. The results showed that SL had a significant protective effect on the anesthetized dog ligating coronary artery model, reduced the degree of myocardial ischemia (Σ-ST), and reduced the scope of myocardial ischemia (N-ST). Meanwhile, SL alleviated ischemic reperfusion damage in ex vivo rat hearts with improved LVEDP and ± dp/dtmax values of the left ventricle. SL reduced the pathological changes of LDH, IL-1ß, MDA, and NO contents, all of which are related to the expression of NF-κB. Further analysis by Bio-Plex array and signal pathway blocker revealed that the phosphorylation of IκB was a key factor for SL to inhibit myocardial ischemic injury, and the regulation of SL on IκB was primarily related to degradation of the IκB protein. These results provided dependable evidence that SL could protect against myocardial ischemic injury through the NF-κB signaling pathway.

10.
J Phys Condens Matter ; 32(3): 035602, 2020 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-31536975

RESUMO

We investigate the valence transition in three-dimensional topological Kondo insulator through slave-boson analysis of periodic Anderson model. By including the effect of intra-atomic Coulomb correlation [Formula: see text] between conduction and local electrons, we find a first-order valence transition from Kondo region to mixed valence state upon ascending of local f- level above a critical [Formula: see text], and this valence transition usually occurs very close to or simultaneously with a topological transition. Near the parameter region of zero-temperature valence transition, rise of temperature can generate a thermal valence transition from mixed valence to Kondo region, accompanied by a first-order topological transition. Remarkably, above a critical [Formula: see text] which is considerably smaller than that generating paramagnetic valence transition, the original continuous antiferromagnetic transition is shifted to first order one, at which a discontinuous valence shift takes place. Upon increasing [Formula: see text], the paramagnetic valence transition approaches then converges with the first-order antiferromagnetic transition, leaving a significant valence shift on the magnetic boundary. The continuous antiferromagnetic transition, first-order antiferromagnetic transition, paramagnetic valence transition and topological transitions are all summarized in a global phase diagram. Our proposed exotic transition processes can help to understand the thermal valence variation as well as the valence shift around the pressure-induced magnetic transition in topological Kondo insulator candidates and in other heavy-fermion systems.

11.
EMBO Mol Med ; 11(11): e9127, 2019 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-31532577

RESUMO

The function of nuclear receptor corepressor 1 (NCoR1) in cardiomyocytes is unclear, and its physiological and pathological implications are unknown. Here, we found that cardiomyocyte-specific NCoR1 knockout (CMNKO) mice manifested cardiac hypertrophy at baseline and had more severe cardiac hypertrophy and dysfunction after pressure overload. Knockdown of NCoR1 exacerbated whereas overexpression mitigated phenylephrine-induced cardiomyocyte hypertrophy. Mechanistic studies revealed that myocyte enhancer factor 2a (MEF2a) and MEF2d mediated the effects of NCoR1 on cardiomyocyte hypertrophy. The receptor interaction domains (RIDs) of NCoR1 interacted with MEF2a to repress its transcriptional activity. Furthermore, NCoR1 formed a complex with MEF2a and class IIa histone deacetylases (HDACs) to suppress hypertrophy-related genes. Finally, overexpression of RIDs of NCoR1 in the heart attenuated cardiac hypertrophy and dysfunction induced by pressure overload. In conclusion, NCoR1 cooperates with MEF2 and HDACs to repress cardiac hypertrophy. Targeting NCoR1 and the MEF2/HDACs complex may be an attractive therapeutic strategy to tackle pathological cardiac hypertrophy.


Assuntos
Cardiomegalia/fisiopatologia , Regulação da Expressão Gênica , Miócitos Cardíacos/fisiologia , Correpressor 1 de Receptor Nuclear/metabolismo , Animais , Técnicas de Silenciamento de Genes , Técnicas de Inativação de Genes , Redes Reguladoras de Genes , Humanos , Fatores de Transcrição MEF2/metabolismo , Camundongos , Camundongos Knockout , Correpressor 1 de Receptor Nuclear/deficiência , Ligação Proteica , Mapeamento de Interação de Proteínas
12.
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
13.
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
14.
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
15.
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
16.
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
17.
Hypertension ; 70(1): 137-147, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28559389

RESUMO

Although antagonists of mineralocorticoid receptor (MR) have been widely used to treat heart failure, the underlying mechanisms are incompletely understood. Recent reports show that T cells play important roles in pathologic cardiac hypertrophy and heart failure. However, it is unclear whether and how MR functions in T cells under these pathologic conditions. We found that MR antagonist suppressed abdominal aortic constriction-induced cardiac hypertrophy and decreased the accumulation and activation of CD4+ and CD8+ T cells in mouse heart. T-cell MR knockout mice manifested suppressed cardiac hypertrophy, fibrosis, and dysfunction compared with littermate control mice after abdominal aortic constriction. T-cell MR knockout mice had less cardiac inflammatory response, which was illustrated by decreased accumulation of myeloid cells and reduced expression of inflammatory cytokines. Less amounts and activation of T cells were observed in the heart of T-cell MR knockout mice after abdominal aortic constriction. In vitro studies showed that both MR antagonism and deficiency repressed activation of T cells, whereas MR overexpression elevated activation of T cells. These results demonstrated that MR blockade in T cells protected against abdominal aortic constriction-induced cardiac hypertrophy and dysfunction. Mechanistically, MR directly regulated T-cell activation and modulated cardiac inflammation. Targeting MR in T cells specifically may be a feasible strategy for more effective treatment of pathologic cardiac hypertrophy and heart failure.


Assuntos
Cardiomegalia/metabolismo , Insuficiência Cardíaca/metabolismo , Antagonistas de Receptores de Mineralocorticoides , Receptores de Mineralocorticoides/metabolismo , Linfócitos T/fisiologia , Animais , Aorta/metabolismo , Aorta/fisiopatologia , Cardiomegalia/etiologia , Cardiomegalia/fisiopatologia , Insuficiência Cardíaca/etiologia , Insuficiência Cardíaca/fisiopatologia , Camundongos , Camundongos Knockout , Antagonistas de Receptores de Mineralocorticoides/metabolismo , Antagonistas de Receptores de Mineralocorticoides/farmacologia
18.
Diabetes ; 66(6): 1535-1547, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28325853

RESUMO

Although the importance of macrophages in nonalcoholic fatty liver disease (NAFLD) and type 2 diabetes mellitus (T2DM) has been recognized, how macrophages affect hepatocytes remains elusive. Mineralocorticoid receptor (MR) has been implicated to play important roles in NAFLD and T2DM. However, cellular and molecular mechanisms are largely unknown. We report that myeloid MR knockout (MRKO) improves glucose intolerance, insulin resistance, and hepatic steatosis in obese mice. Estrogen signaling is sufficient and necessary for such improvements. Hepatic gene and protein expression suggests that MRKO reduces hepatic lipogenesis and lipid storage. In the presence of estrogen, MRKO in macrophages decreases lipid accumulation and increases insulin sensitivity of hepatocytes through hepatocyte growth factor (HGF)/Met signaling. MR directly regulates estrogen receptor 1 (Esr1 [encoding ERα]) in macrophages. Knockdown of hepatic Met eliminates the beneficial effects of MRKO in female obese mice. These findings identify a novel MR/ERα/HGF/Met pathway that conveys metabolic signaling from macrophages to hepatocytes in hepatic steatosis and insulin resistance and provide potential new therapeutic strategies for NAFLD and T2DM.


Assuntos
Receptor alfa de Estrogênio/genética , Fator de Crescimento de Hepatócito/metabolismo , Hepatócitos/metabolismo , Resistência à Insulina/genética , Macrófagos/metabolismo , Camundongos Obesos/genética , Hepatopatia Gordurosa não Alcoólica/genética , Proteínas Proto-Oncogênicas c-met/genética , Receptores de Mineralocorticoides/genética , Animais , Células Cultivadas , Imunoprecipitação da Cromatina , Diabetes Mellitus Tipo 2/metabolismo , Ensaio de Imunoadsorção Enzimática , Receptor alfa de Estrogênio/metabolismo , Ácidos Graxos não Esterificados/metabolismo , Feminino , Técnicas de Silenciamento de Genes , Teste de Tolerância a Glucose , Immunoblotting , Insulina/metabolismo , Lipogênese , Masculino , Camundongos , Camundongos Knockout , Camundongos Obesos/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Proteínas Proto-Oncogênicas c-met/metabolismo , Células RAW 264.7 , Transdução de Sinais , Triglicerídeos/metabolismo
19.
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
20.
Zhongguo Zhong Yao Za Zhi ; 42(23): 4548-4555, 2017 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-29376251

RESUMO

Cerebral malaria (CM), a severe neurological syndrome caused by Plasmodium falciparum infection, is a serious life-threatening disease with a high mortality. Survivors' persistent brain injury is manifested as long-term neurocognitive disorders. The main neuropathological feature of CM is the sequestration of parasited red blood cells (pRBCs) in cerebral microvessels. Other neuropathological features of CM include petechial hemorrhage in the brain parenchyma, annular hemorrhage, extensive brain endothelial cell activation, and focal endothelial cell injury and necrosis. However, its pathogenesis is still not clear. Currently, some studies have suggested that the pathogenesis of cerebral malaria mainly include pRBC adhesion, inflammatory reaction cascade, vascular leakage damage and brain hypoxia. Studies have shown that the biomarkers currently used as diagnostic and prognostic markers for CM include C-X-C motif chemokine ligand 10 (CXCL10), CXC chemokine ligand 4 (CXCL4), angiopoietin (Ang). In this paper, we systematically summarize the basic and clinical research for cerebral malaria in recent years and the latest literatures for drug studies, and focused on the advance of studies on cerebral malaria and its immunologic mechanism in the recent three years in the aspects of cytokines, immune cells, regulatory factors and biomarkers, so as to provide references for relevant studies.


Assuntos
Encéfalo/patologia , Eritrócitos/parasitologia , Inflamação/parasitologia , Malária Cerebral/patologia , Biomarcadores/sangue , Quimiocinas/sangue , Humanos , Malária Cerebral/imunologia
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