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1.
J Oral Sci ; 62(4): 423-426, 2020 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-32863319

RESUMO

PURPOSE: Diabetes causes hyperglycemic disorders due to insufficient activity of insulin, and it also increases blood glucose level. Recent studies have reported the relationship between diabetes and periodontal disease. Periodontitis is advanced by inflammatory cytokines stimulated with LPS. The purpose of this study was to investigate the effects of hyperglycemia on the expression of inflammatory cytokines induced by LPS in osteoblasts. METHODS: Cells were cultured for 7 and 14 days in the presence or absence of LPS and glucose. The expression mRNA level of IL-6, RANKL and OCN was determined using real-time PCR. The protein expression of IL-6 and RANKL was also measured using ELISA. RESULTS: LPS and glucose increased the mRNA expression of IL-6, coupled with a decrease in the mRNA expression of OCN, which is associated with IL-6 and glucose. It also increased the protein expression of IL-6 compared to LPS. However, LPS+Glucose did not affect the mRNA and protein expression of RANKL. Furthermore, GLUT4 inhibitor, WZB117, blocked the stimulatory effect of glucose on LPS-induced IL-6 mRNA expression. WZB117 did not affect LPS-reduced OCN mRNA expression. CONCLUSION: These results suggest that high glucose levels increase LPS-induced IL-6 expression mediated by GLUT4.


Assuntos
Transportador de Glucose Tipo 4/fisiologia , Interleucina-6 , Lipopolissacarídeos , Glucose , Proteínas Facilitadoras de Transporte de Glucose , Interleucina-6/metabolismo , Osteoblastos/metabolismo
2.
Nan Fang Yi Ke Da Xue Xue Bao ; 40(4): 525-530, 2020 Apr 30.
Artigo em Chinês | MEDLINE | ID: mdl-32895145

RESUMO

OBJECTIVE: To investigate the molecular mechanism underlying the inhibitory effect of propofol on pyroptosis of macrophages. METHODS: Macrophages derived from bone marrow were extracted and divided into three groups: control group, LPS+ATP group and propofol+LPS+ATP group. The control group was not given any treatment; LPS+ATP group was given LPS 1 µg/mL stimulation for 4 h, then ATP 4 mM stimulation for 1 h; Propofol+LPS+ATP group was given propofol+LPS 1 µg/mL stimulation for 4 h, then ATP stimulation for 1 h. After treatment, the supernatant and cells of cell culture were collected. the cell activity was detected by CCK8 and flow cytometry. The inflammatory cytokines IL-1ßand IL-18 were detected by Elisa. Western blot was used to detect the expression of caspase-1 protein and TLR4 on cell membran Immunohistochemical fluorescence was used to detect apoptosis of cells. RESULTS: LPS+ATP significantly decreased the viability of the macrophages and increased the cellular production of IL-1ß and IL-18, activation of caspase-1 protein and the expression of TLR-4 on the cell membrane (P < 0.05). Treatment with propofol obviously reversed the changes induced by LPS+ATP. CONCLUSIONS: LPS+ATP can induce pyroptosis of mouse bone marrow-derived macrophages, and propofol effectively inhibits such cell death, suggesting that propofol anesthesia is beneficial during operation and helps to regulate the immune function of in patients with sepsis.


Assuntos
Piroptose , Animais , Caspase 1 , Lipopolissacarídeos , Macrófagos , Camundongos , Propofol
3.
Rev Lat Am Enfermagem ; 28: e3290, 2020 Sep 07.
Artigo em Inglês, Português, Espanhol | MEDLINE | ID: mdl-32901764

RESUMO

OBJECTIVE: to analyze variations in body temperature and in plasma nitrate and lactate concentrations in rats submitted to the experimental sepsis model. METHOD: a total of 40 rats divided equally into five groups. The induction of endotoxemia was performed with intravenous administration of lipopolysaccharide, 0.5 mg/Kg, 1.5 mg/Kg, 3.0 mg/Kg, and 10 mg/Kg, respectively. The control group received 0.5 mL of saline solution. The experiment lasted six hours, with evaluations performed at 0 (baseline data), 2nd, 4th, and 6thhours. RESULTS: The animals that received doses up to 3.0 mg/kg showed a significant increase in body temperature compared to the group with 10 mg/kg, which showed a decrease in these values. The increase in plasma nitrate and lactate concentrations in the groups with lipopolysaccharide was significantly higher than in the group that received the saline solution and was correlated with the increase in body temperature. CONCLUSION: the variations in body temperature observed in this study showed the dose-dependent effect of lipopolysaccharide and were correlated with the increase in the concentrations of nitrate and plasma lactate biomarkers. The implications of this study are the importance of monitoring body temperature, together with the assessment of these pathophysiological markers, which suggest worsening in the prognosis of sepsis.


Assuntos
Endotoxemia , Sepse , Animais , Biomarcadores , Modelos Animais de Doenças , Lipopolissacarídeos , Ratos
4.
Nat Commun ; 11(1): 4561, 2020 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-32917873

RESUMO

The protein high-mobility group box 1 (HMGB1) is released into the extracellular space in response to many inflammatory stimuli, where it is a potent signaling molecule. Although research has focused on downstream HMGB1 signaling, the means by which HMGB1 exits the cell is controversial. Here we demonstrate that HMGB1 is not released from bone marrow-derived macrophages (BMDM) after lipopolysaccharide (LPS) treatment. We also explore whether HMGB1 is released via the pore-forming protein gasdermin D after inflammasome activation, as is the case for IL-1ß. HMGB1 is only released under conditions that cause cell lysis (pyroptosis). When pyroptosis is prevented, HMGB1 is not released, despite inflammasome activation and IL-1ß secretion. During endotoxemia, gasdermin D knockout mice secrete HMGB1 normally, yet secretion of IL-1ß is completely blocked. Together, these data demonstrate that in vitro HMGB1 release after inflammasome activation occurs after cellular rupture, which is probably inflammasome-independent in vivo.


Assuntos
Proteína HMGB1/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Macrófagos/metabolismo , Proteínas de Ligação a Fosfato/metabolismo , Animais , Modelos Animais de Doenças , Endotoxemia/metabolismo , Feminino , Proteína HMGB1/genética , Inflamassomos/metabolismo , Interleucina-1beta/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Lipopolissacarídeos/efeitos adversos , Macrófagos/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas de Ligação a Fosfato/genética , Piroptose , Transdução de Sinais
5.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi ; 32(4): 367-373, 2020 Jul 10.
Artigo em Chinês | MEDLINE | ID: mdl-32935510

RESUMO

OBJECTIVE: To investigate the polarization of human acute monocytic leukemia THP-1 cells-derived macrophages induced by Nippostrongylus brasiliensis proteins in vitro, so as to provide insights into the elucidation of the mechanisms underlying host immune responses to hookworm infections. METHODS: The in-vitro culture of N. brasiliensis was established and maintained in the laboratory, and the third- (L3) and fifth-stage larvae (L5) were collected under a sterile condition for preparation of L3 and L5 proteins. The in-vitro culture of THP-1 cells was established, stimulated with 500 ng/mL PMA to yield M0 macrophages that were adherent to the plate wall. The LPS + IFN-γ group, IL-4 + IL-13 group, L3 protein group and L5 protein group were given stimulation with 500 ng/mL LPS plus 100 ng/mL IFN-γ, IL-4 and IL-13 (both 100 ng/mL), L3 protein (5 mg/mL) and L5 protein (5 mg/mL), respectively, while the negative control group was given no stimulation. The cell morphology was observed using microscopy, the mRNA expression of M1/M2 macrophages-specific genes was quantified using a quantitative real-time PCR (qPCR) assay, and the surface markers of M1/M2 macrophages were detected using flow cytometry, while the levels of cytokines secreted by M1/M2 macrophages were measured using enzyme-linked immunosorbent assay (ELISA) following stimulations, so as to examine the polarization of THP-1-derived macrophages induced by N. brasiliensis proteins in vitro. RESULTS: Following stimulation with PMA, THP-1 cells appeared wall-adherent M0 macrophages, and polarized to typical M1 macrophages following stimulation with LPS + IFN-γ, and typical M2 macrophages following stimulation with IL-4 + IL-13, IL-3 protein or L5 protein. There was a significant difference in the proportion of M1 macrophages among the negative control group, the LPS + IFN-γ group, the IL-4 + IL-13 group, the L3 protein group and the L5 protein group (χ2 = 3 721.00, P < 0.001), with the highest proportion detected in the LPS + IFN-γ group, and there was also a significant difference in the proportion of M2 macrophages among groups (χ2 = 105.43, P < 0.001). There were significant differences among groups in terms of the mRNA expression of CCL2 (F = 191.95, P < 0.001), TNF-α (F = 129.95, P < 0.001), IL-12b (F = 82.89, P < 0.001), PPARγ (F = 11.30, P < 0.001), IL-10 (F = 9.51, P < 0.001) and Mrc1 genes (F = 12.35, P < 0.001). In addition, there were significant differences in the proportion of positive CD86 and CD206 expression among groups (χ2 = 24 004.33 and 832.50, P < 0.001). Higher IL-1ß and TNF-α levels were measured in the LPS + IFN-γ group than in the IL-4 + IL-13 group, the L3 protein group and the L5 protein group (P < 0.001), and greater TGF-ß1 and IL-10 levels were seen in the IL-4 + IL-13 group, the L3 protein group and the L5 protein group than in the negative control group and the LPS + IFN-γ group (P < 0.05). CONCLUSIONS: Both L3 and L5 proteins of N. brasiliensis may induce the polarization of THP-1-derived macrophages to M2 type in vitro.


Assuntos
Leucemia Monocítica Aguda , Animais , Antígenos de Helmintos/farmacologia , Criança , Humanos , Lipopolissacarídeos , Macrófagos/efeitos dos fármacos , Nippostrongylus/química , Células THP-1/citologia , Células THP-1/efeitos dos fármacos
6.
Zhonghua Jie He He Hu Xi Za Zhi ; 43(9): 765-771, 2020 Sep 12.
Artigo em Chinês | MEDLINE | ID: mdl-32894910

RESUMO

Objective: To explore the protective effect of human adipose-derived mesenchymal stem cells (AD-MSCs) and liraglutide on lipopolysaccharide (LPS) -induced acute lung injury (ALI) . Methods: AD-MSCs were cultured in vitro and randomly divided into 3 groups: control group, LPS group (30 mg/L) , and LPS (30 mg/L) +liraglutide (10 nM) group. MTT assay was used to detect the proliferation of AD-MSCs at 6, 24, 48 and 72 h. Annexin V-FITC / PI double staining flow cytometry was used to detect the apoptosis of the cells. Western blot was used to detect the expression of apoptotic proteins cleaved caspase-3, Bax and Bcl-2 at 72 h in vitro. For the in vivo experiment, 60 male SPF BALB/c mice were randomly divided into 5 groups: control group, ALI group, ALI+AD-MSCs group, ALI+Liraglutide group, and ALI+AD-MSCs+Lraglutide group. The mice were sacrificed on day 2 and day 7 after LPS treatment. HE staining was used to examine the pathological changes of the lungs of mice, and the scores of lung injury were measured. The lung tissues of mice were examined by immunohistochemistry, and the expression of the marker protein Nanog of mesenchymal stem cells was observed. BALF was collected, and the number of BALF neutrophils was counted by Rayleigh Giemsa staining. The wet/dry specific gravity of mouse lung tissue was recorded. Results: The apoptosis of AD-MSCs stimulated by LPS was significantly higher than that of the control group (P<0.05) , and the proliferation of AD-MSCs at 6, 24, 48 and 72 h was significantly lower than that of the control group (all P<0.05) . The addition of Liraglutide reduced the apoptosis of AD-MSCs (P<0.05) , and promoted the proliferation of AD-MSC at 6, 24, 48 and 72 h. Compared with the control group, in the 2 d and 7 d model groups, the lung injury pathology of ALI group had lung injury, increased number of neutrophils in BALF (65.63±1.34 vs 1.74±0.17, 51.67±1.35 vs 1.55±0.13) ×10(4)/ml (all P<0.05) , and increased W/D of lung tissues. The expression level of Nanog protein was low in the 7 d model group. Compared with the ALI group, in 2 d and 7 d model groups, the ALI+AD-MSCs group, the ALI+liraglutide group, and the ALI+AD-MSCs+liraglutide group showed reduced lung injury pathology, and the number of neutrophils was decreased, (37.04±1.23, 29.17±0.68) ×10(4) / ml (all P<0.05) in the ALI+AD -MSCs group, (39.58±1.67, 35.42±0.25) ×10(4) / ml in the ALI+Liraglutide group (all P<0.05) and (28.54±0.37, 21.46±0.89) ×10(4)/ml (all P<0.05) in the ALI+AD-MSCs+Liraglutide group. Lung tissue W/D in the ALI+AD-MSCs group, ALI+Liraglutide group and ALI+AD-MSCs+Liraglutide group showed the same trend. Nanog protein expression increased in the 7 d model group. Conclusions: AD-MSCs play a protective role in acute lung injury in mice under the synergistic effect of liraglutide.


Assuntos
Lesão Pulmonar Aguda , Células-Tronco Mesenquimais , Animais , Lipopolissacarídeos , Liraglutida , Pulmão , Masculino , Camundongos , Camundongos Endogâmicos BALB C
7.
Zhongguo Zhong Yao Za Zhi ; 45(16): 3938-3944, 2020 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-32893592

RESUMO

The aim of this paper was to observe the anti-inflammatory action and mechanism of Lonicerae Japonicae Flos extract and Lonicerae Flos extract in xylene-induced ear swelling experiment and lipopolysaccharide(LPS)-induced RAW264.7 cell inflammatory model. In vivo, xylene-induced mouse auricle swelling model was used to detect the auricle swelling degree and swelling inhibition rate of Lonicerae Japonicae Flos extract and Lonicerae Flos extract; the pathological changes of mice auricle were observed by hematoxylin eosin(HE) staining. In vitro, RAW264.7 inflammatory cell model was induced by LPS, where the cytotoxic effects of Lonicerae Japonicae Flos extract and Lonicerae Flos extract on RAW264.7 cells were detected by CCK-8 method; Griess method was used to detect the effect of Lonicerae Japonicae Flos extract and Lonicerae Flos extract on nitric oxide(NO) production, and ELISA method was used to detect the content of inflammatory factors interleukin-6(IL-6), IL-1ß, and tumor necrosis factor-α(TNF-α). At last, Western blot was used to detect the protein changes of cyclooxygenase 1(COX1), COX2 and inducible nitric oxide synthetase(iNOS) for RAW264.7 cells. The results showed that both Lonicerae Japonicae Flos extract and Lonicerae Flos extract could significantly inhibit the degree of auricle swelling caused by xylene in mice and the inhibition rate was positively correlated with the drug dose. Furthermore, both of them could reduce the infiltration of lymphocytes and neutrophils in mouse ear tissues. For in vitro experiments, both Lonicerae Japonicae Flos extract and Lonicerae Flos extract inhibited NO secretion in RAW264.7 cells, down-regulated the release of IL-1ß, IL-6 and TNF-α, and down-regulated iNOS protein and COX2, NF-κB p65 protein content. In conclusion, both Lonicerae Japonicae Flos extract and Lonicerae Flos extract have good anti-inflammatory effect, and the mechanism may be related with the inhibition of NF-κB signaling pathway.


Assuntos
Lonicera , Animais , Anti-Inflamatórios , Lipopolissacarídeos , Camundongos , Extratos Vegetais
8.
Nat Commun ; 11(1): 4596, 2020 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-32929083

RESUMO

Earlier studies indicate that either the canonical or non-canonical pathways of inflammasome activation have a limited role on malaria pathogenesis. Here, we report that caspase-8 is a central mediator of systemic inflammation, septic shock in the Plasmodium chabaudi-infected mice and the P. berghei-induced experimental cerebral malaria (ECM). Importantly, our results indicate that the combined deficiencies of caspases-8/1/11 or caspase-8/gasdermin-D (GSDM-D) renders mice impaired to produce both TNFα and IL-1ß and highly resistant to lethality in these models, disclosing a complementary, but independent role of caspase-8 and caspases-1/11/GSDM-D in the pathogenesis of malaria. Further, we find that monocytes from malaria patients express active caspases-1, -4 and -8 suggesting that these inflammatory caspases may also play a role in the pathogenesis of human disease.


Assuntos
Caspase 8/metabolismo , Inflamação/patologia , Malária Cerebral/enzimologia , Animais , Encéfalo/patologia , Caspase 1/metabolismo , Células Dendríticas/metabolismo , Ativação Enzimática , Matriz Extracelular/metabolismo , Regulação da Expressão Gênica , Humanos , Interferon gama/metabolismo , Interleucina-1beta/metabolismo , Lipopolissacarídeos , Malária Cerebral/genética , Camundongos Endogâmicos C57BL , Monócitos/metabolismo , Plasmodium chabaudi/fisiologia , Baço/metabolismo , Receptores Toll-Like/metabolismo
9.
J Environ Pathol Toxicol Oncol ; 39(3): 235-245, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32865915

RESUMO

Ulcerative colitis (UC) is an intractable ailment, in which may chronic inflammations/ulcerations may develop in the mucosal lining of the colon with multiple recurrences. Various drugs such as steroids, immunosuppressants, and antibiotics are extensively used to treat UC. The patients suffer from adverse effects of these advanced drugs. So, they need a harmless therapeutic agent from natural sources. The therapeutic D-carvone has an anti-inflammatory action against the investigational colon cancer models. Therefore, we analyzed the effect of D-carvone on dextran sulfate sodium (DSS) provoked colitis model in mice as follows: Group I: noncolitis healthy control mice; Group II: ulcerative colitis mice models; Group III: D-carvone (40 mg/kg) + ulcerative colitis models; Group IV: sulfasalazine (50 mg/kg) + ulcerative colitis models. On the 8th day, the experimental study was terminated and serum samples and colon tissues were processed for further analysis. The effect of D-carvone at different concentration was studied on the LPS challenged RAW 264.7 cell lines. The D-carvone (40 mg/kg) treatment maintained the colon length and decreased disease activity index (DAI) score in UC animals. The increased antioxidant enzymes status and decreased oxidative stress and pro-inflammatory markers were noted in the D-carvone (40 mg/ kg) + UC mice. Histopathological study of colon tissue of D-carvone (40 mg/kg) treated UC mice displayed less mucosal damage and improved crypt integrity and goblet cells compared with DSS only provoked mice. The im-munohistochemical expression of iNOS and COX-2 was drastically diminished in the D-carvone treated UC mice. D-carvone (40 mg/kg) treatment appreciably diminished the LPS provoked NO production and pro-inflammatory modulators in the RAW 264.7 macrophage cell lines. These findings proved that D-carvone has a potential therapeutic effect to prevent LPS induced inflammation in in vitro cells and chemically induced ulcerative colitis in vivo models.


Assuntos
Anti-Inflamatórios/uso terapêutico , Colite Ulcerativa/tratamento farmacológico , Monoterpenos Cicloexânicos/uso terapêutico , Ciclo-Oxigenase 2/metabolismo , Macrófagos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Fator de Necrose Tumoral alfa/sangue , Animais , Anti-Inflamatórios/administração & dosagem , Sobrevivência Celular/efeitos dos fármacos , Colite Ulcerativa/imunologia , Colite Ulcerativa/patologia , Colo/efeitos dos fármacos , Colo/imunologia , Colo/patologia , Monoterpenos Cicloexânicos/administração & dosagem , Sulfato de Dextrana , Modelos Animais de Doenças , Lipopolissacarídeos , Macrófagos/imunologia , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Células RAW 264.7
10.
Proc Natl Acad Sci U S A ; 117(37): 22984-22991, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32868431

RESUMO

Immune evasion through membrane remodeling is a hallmark of Yersinia pestis pathogenesis. Yersinia remodels its membrane during its life cycle as it alternates between mammalian hosts (37 °C) and ambient (21 °C to 26 °C) temperatures of the arthropod transmission vector or external environment. This shift in growth temperature induces changes in number and length of acyl groups on the lipid A portion of lipopolysaccharide (LPS) for the enteric pathogens Yersinia pseudotuberculosis (Ypt) and Yersinia enterocolitica (Ye), as well as the causative agent of plague, Yersinia pestis (Yp). Addition of a C16 fatty acid (palmitate) to lipid A by the outer membrane acyltransferase enzyme PagP occurs in immunostimulatory Ypt and Ye strains, but not in immune-evasive Yp Analysis of Yp pagP gene sequences identified a single-nucleotide polymorphism that results in a premature stop in translation, yielding a truncated, nonfunctional enzyme. Upon repair of this polymorphism to the sequence present in Ypt and Ye, lipid A isolated from a Yp pagP+ strain synthesized two structures with the C16 fatty acids located in acyloxyacyl linkage at the 2' and 3' positions of the diglucosamine backbone. Structural modifications were confirmed by mass spectrometry and gas chromatography. With the genotypic restoration of PagP enzymatic activity in Yp, a significant increase in lipid A endotoxicity mediated through the MyD88 and TRIF/TRAM arms of the TLR4-signaling pathway was observed. Discovery and repair of an evolutionarily lost lipid A modifying enzyme provides evidence of lipid A as a crucial determinant in Yp infectivity, pathogenesis, and host innate immune evasion.


Assuntos
Aciltransferases/imunologia , Evasão da Resposta Imune/imunologia , Imunidade Inata/imunologia , Lipídeo A/imunologia , Yersinia pestis/imunologia , Animais , Evolução Biológica , Linhagem Celular , Linhagem Celular Tumoral , Células HEK293 , Humanos , Leucócitos Mononucleares/imunologia , Lipopolissacarídeos/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Polimorfismo de Nucleotídeo Único/imunologia , Células THP-1/imunologia , Células U937 , Yersinia pseudotuberculosis/imunologia
11.
PLoS Pathog ; 16(9): e1008811, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32903274

RESUMO

Damage-associated molecular patterns (DAMPs) are endogenous molecules activating the immune system upon release from injured cells. Here we show that the IFI16 protein, once freely released in the extracellular milieu of chronically inflamed tissues, can function as a DAMP either alone or upon binding to lipopolysaccharide (LPS). Specifically, using pull-down and saturation binding experiments, we show that IFI16 binds with high affinity to the lipid A moiety of LPS. Remarkably, IFI16 DAMP activity is potentiated upon binding to subtoxic concentrations of strong TLR4-activating LPS variants, as judged by TLR4-MD2/TIRAP/MyD88-dependent IL-6, IL-8 and TNF-α transcriptional activation and release in stimulated monocytes and renal cells. Consistently, using co-immunoprecipitation (co-IP) and surface plasmon resonance (SPR) approaches, we show that IFI16 is a specific TLR4-ligand and that IFI16/LPS complexes display a faster stimulation turnover on TLR4 than LPS alone. Altogether, our findings point to a novel pathomechanism of inflammation involving the formation of multiple complexes between extracellular IFI16 and subtoxic doses of LPS variants, which then signal through TLR4.


Assuntos
Inflamação/imunologia , Neoplasias Renais/imunologia , Leucemia/imunologia , Lipopolissacarídeos/metabolismo , Proteínas Nucleares/metabolismo , Fosfoproteínas/metabolismo , Receptor 4 Toll-Like/metabolismo , Humanos , Inflamação/metabolismo , Inflamação/patologia , Neoplasias Renais/metabolismo , Neoplasias Renais/patologia , Leucemia/metabolismo , Leucemia/patologia , Fator 88 de Diferenciação Mieloide/metabolismo , NF-kappa B/metabolismo , Transdução de Sinais , Células Tumorais Cultivadas
12.
Zhonghua Yi Xue Za Zhi ; 100(35): 2779-2784, 2020 Sep 22.
Artigo em Chinês | MEDLINE | ID: mdl-32972060

RESUMO

Objectives: To investigated whether berberine could ameliorate septic cardiomyopathy in a rat model of sepsis and it's mechanisms. Methods: SD rats were divided into 3 groups: sepsis group (LPS group), rats were intraperitoneal injected of LPS (10 mg/kg); Berberine intervention group (Ber group), Ber (50 mg/kg, one time per day) was gavage fed 3 days before intraperitoneally injection of lipopolysaccharides (LPS); control group (Con group), rats were gavage fed with double distilled water (2 ml/100 g, one time per day) 3 days before intraperitoneal injection of normal saline (1 ml/100 g). LPS group and the Ber group was further divided into 3 subgroups (n=6), and the follow-up experiments were conducted at 6 h, 24 h and 48 h after LPS injection (of which 48 h subgroup rats were gavage fed with Ber/saline at 24 h). Left ventricular systolic pressure (LVSP), left ventricular end-diastolic pressure (LVEDP), and the maximum rate of change of left ventricular pressure (±dp/dtmax) were monitored, the level of cardiac troponin T (cTnT), tumor necrosis factor (TNF)-α and interleukin (IL)-1ß was detected by ELISA method, HE staining of myocardial tissues was done to observe myocardial injury; Western blotting method was used to detect the expression of toll-like receptor 4(TLR4) protein in rat myocardial tissue, the level of myocardial cell nucleus protein p65 was detected to reflects the degree of NF-κB activation. The correlation of factors was analyzed with Pearson correlation analysis. Results: Pre-treatment with berberine stabilized cardiac hemodynamics and improved the systolic function and diastolic function in the heart of LPS-induced rats, as evidenced by the partial recovery of the reduced±dp/dtmax and LVSP, as well as the decreased LVEDP. Compared with the LPS group, the Ber group showed improved myocardial injury, as demonstrated by decreased cTnT at each time point. HE staining results showed that berberine decreased inflammatory cell infiltration and LPS-induced cell swelling. These effects were observed early at 6 hours, severe at 24 hours, and become more serious at 48 hours after LPS injection. Further, TLR4 and NF-κB p65 subunits, which were the two key factors of the TLR4/NF-κB signaling, were upregulated in the LPS group and attenuated in the Ber group. Consistently, the expression levels of the downstream cytokines TNF-α and IL-1ß were lower in the Ber group than those in the LPS group (all P<0.05). Myocardial injury markers were positively correlated with the markers of TLR4/NF-κB signals and the downstream host inflammatory factors (all P<0.05). Conclusions: Berberine can improve myocardial injury and cardiac function in sepsis rats, the mechanism is considered to be related to that it can inhibit the activation of TLR4/NF-κB signaling pathway induced by LPS and further reducing the production of TNF-α and IL-1ß.


Assuntos
Berberina/uso terapêutico , Sepse , Animais , Lipopolissacarídeos , NF-kappa B , Ratos , Ratos Sprague-Dawley , Fator de Necrose Tumoral alfa
13.
Life Sci ; 259: 118352, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32860804

RESUMO

AIMS: Lipopolysaccharide (LPS) induces inflammatory cholestasis by impairing expression, localization, and function of carriers involved in bile formation, e.g. bile salt export pump (Bsep) and multidrug resistance-associated protein 2 (Mrp2). A specific therapy against this disease is still lacking. Therefore, we evaluated the anticholestatic effects of spironolactone (SL), a PXR ligand that regulates bile salt homeostasis, up-regulates Mrp2, and bears anti-inflammatory properties. MAIN METHODS: Male Wistar rats were divided into four groups: Control, SL (83.3 mg/kg/day of SL, i.p., for 3 days), LPS (2.5 mg/kg/day, i.p., at 8 am of the last 2 days, and 1.5 mg/kg/day at 8 pm of the last day), and SL + LPS. Biliary and plasma parameters and the expression, function, and localization of Mrp2 and Bsep were evaluated. KEY FINDINGS: SL partially prevented LPS-induced drop of basal bile flow by normalizing the bile salt-independent fraction of bile flow (BSIBF), via improvement of glutathione output. This was due to a recovery in Mrp2 transport function, the major canalicular glutathione transporter, estimated by monitoring the output of its exogenously administered substrate dibromosulfophthalein. SL counteracted the LPS-induced downregulation of Mrp2, but not that of Bsep, at both mRNA and protein levels. LPS induced endocytic internalization of both transporters, visualized by immunofluorescence followed by confocal microscopy, and SL partially prevented this relocalization. SL did not prevent the increase in IL-1ß, IL-6, and TNF-α plasma levels. SIGNIFICANCE: SL prevents the impairment in Mrp2 expression and localization, and the resulting recovery of Mrp2 function normalizes the BSIBF by improving glutathione excretion.


Assuntos
Transportadores de Cassetes de Ligação de ATP/metabolismo , Colestase/tratamento farmacológico , Espironolactona/uso terapêutico , Membro 11 da Subfamília B de Transportadores de Cassetes de Ligação de ATP/metabolismo , Animais , Bile/metabolismo , Colestase/sangue , Colestase/metabolismo , Citocinas/sangue , Regulação da Expressão Gênica/efeitos dos fármacos , Lipopolissacarídeos/efeitos adversos , Masculino , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase em Tempo Real
14.
Science ; 369(6508): 1210-1220, 2020 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-32788292

RESUMO

Coronavirus disease 2019 (COVID-19) represents a global crisis, yet major knowledge gaps remain about human immunity to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We analyzed immune responses in 76 COVID-19 patients and 69 healthy individuals from Hong Kong and Atlanta, Georgia, United States. In the peripheral blood mononuclear cells (PBMCs) of COVID-19 patients, we observed reduced expression of human leukocyte antigen class DR (HLA-DR) and proinflammatory cytokines by myeloid cells as well as impaired mammalian target of rapamycin (mTOR) signaling and interferon-α (IFN-α) production by plasmacytoid dendritic cells. By contrast, we detected enhanced plasma levels of inflammatory mediators-including EN-RAGE, TNFSF14, and oncostatin M-which correlated with disease severity and increased bacterial products in plasma. Single-cell transcriptomics revealed a lack of type I IFNs, reduced HLA-DR in the myeloid cells of patients with severe COVID-19, and transient expression of IFN-stimulated genes. This was consistent with bulk PBMC transcriptomics and transient, low IFN-α levels in plasma during infection. These results reveal mechanisms and potential therapeutic targets for COVID-19.


Assuntos
Betacoronavirus/imunologia , Infecções por Coronavirus/imunologia , Pneumonia Viral/imunologia , Citocinas/sangue , DNA Bacteriano/sangue , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Feminino , Citometria de Fluxo , Antígenos HLA-DR/análise , Humanos , Imunidade , Imunidade Inata , Imunoglobulinas/sangue , Imunoglobulinas/imunologia , Mediadores da Inflamação/sangue , Interferon Tipo I/metabolismo , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/metabolismo , Lipopolissacarídeos/sangue , Masculino , Células Mieloides/imunologia , Células Mieloides/metabolismo , Pandemias , Transdução de Sinais , Análise de Célula Única , Biologia de Sistemas , Serina-Treonina Quinases TOR/metabolismo , Transcrição Genética , Transcriptoma
15.
Planta Med ; 86(13-14): 1032-1042, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32757200

RESUMO

Three previously undescribed natural products, phomopsinin A - C (1:  - 3: ), together with three known compounds, namely, cis-hydroxymellein (4: ), phomoxanthone A (5: ) and cytochalasin L-696,474 (6: ), were isolated from the solid culture of Phomopsis sp. CAM212, an endophytic fungus obtained from Garcinia xanthochymus. Their structures were determined on the basis of spectroscopic data, including IR, NMR, and MS. The absolute configurations of 1: and 2: were assigned by comparing their experimental and calculated ECD spectra. Acetylation of compound 1: yielded 1A: , a new natural product derivative that was tested together with other isolated compounds on lipopolysaccharide-stimulated RAW 264.7 cells. Cytochalasin L-696,474 (6: ) was found to significantly inhibit nitric oxide production, but was highly cytotoxic to the treated cells, whereas compound 1: slightly inhibited nitric oxide production, which was not significantly different compared to lipopolysaccharide-treated cells. Remarkably, the acetylated derivative of 1: , compound 1A: , significantly inhibited nitric oxide production with an IC50 value of 14.8 µM and no cytotoxic effect on treated cells, thereby showing the importance of the acetyl group in the anti-inflammatory activity of 1A: . The study of the mechanism of action revealed that 1A: decreases the expression of inducible nitric oxide synthase, cyclooxygenase 2, and proinflammatory cytokine IL-6 without an effect on IL-1ß expression. Moreover, it was found that 1A: exerts its anti-inflammatory activity in lipopolysaccharide-stimulated RAW 264.7 macrophage cells by downregulating the activation of ERK1/2 and by preventing the translocation of nuclear factor κB. Thus, derivatives of phomopsinin A (1: ), such as compound 1A: , could provide new anti-inflammatory leads.


Assuntos
Policetídeos/farmacologia , Animais , Ciclo-Oxigenase 2 , Lipopolissacarídeos , Sistema de Sinalização das MAP Quinases , Camundongos , Inibidor de NF-kappaB alfa , NF-kappa B , Óxido Nítrico , Óxido Nítrico Sintase Tipo II , Transdução de Sinais
16.
Nat Commun ; 11(1): 3816, 2020 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-32732870

RESUMO

Detection of microbial components such as lipopolysaccharide (LPS) by Toll-like receptor 4 (TLR4) on macrophages induces a robust pro-inflammatory response that is dependent on metabolic reprogramming. These innate metabolic changes have been compared to aerobic glycolysis in tumour cells. However, the mechanisms by which TLR4 activation leads to mitochondrial and glycolytic reprogramming are unknown. Here we show that TLR4 activation induces a signalling cascade recruiting TRAF6 and TBK-1, while TBK-1 phosphorylates STAT3 on S727. Using a genetically engineered mouse model incapable of undergoing STAT3 Ser727 phosphorylation, we show ex vivo and in vivo that STAT3 Ser727 phosphorylation is critical for LPS-induced glycolytic reprogramming, production of the central immune response metabolite succinate and inflammatory cytokine production in a model of LPS-induced inflammation. Our study identifies non-canonical STAT3 activation as the crucial signalling intermediary for TLR4-induced glycolysis, macrophage metabolic reprogramming and inflammation.


Assuntos
Interleucina-1beta/metabolismo , Macrófagos/metabolismo , Fator de Transcrição STAT3/metabolismo , Receptor 4 Toll-Like/metabolismo , Animais , Linhagem Celular , Células Cultivadas , Expressão Gênica , Glicólise/efeitos dos fármacos , Inflamação/genética , Inflamação/metabolismo , Interleucina-1beta/genética , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Fosforilação , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Fator de Transcrição STAT3/genética , Serina/genética , Serina/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Fator 6 Associado a Receptor de TNF/genética , Fator 6 Associado a Receptor de TNF/metabolismo , Receptor 4 Toll-Like/genética
17.
Nat Commun ; 11(1): 3797, 2020 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-32732998

RESUMO

Receptor-mediated perception of surface-exposed carbohydrates like lipo- and exo-polysaccharides (EPS) is important for non-self recognition and responses to microbial associated molecular patterns in mammals and plants. In legumes, EPS are monitored and can either block or promote symbiosis with rhizobia depending on their molecular composition. To establish a deeper understanding of receptors involved in EPS recognition, we determined the structure of the Lotus japonicus (Lotus) exopolysaccharide receptor 3 (EPR3) ectodomain. EPR3 forms a compact structure built of three putative carbohydrate-binding modules (M1, M2 and LysM3). M1 and M2 have unique ßαßß and ßαß folds that have not previously been observed in carbohydrate binding proteins, while LysM3 has a canonical ßααß fold. We demonstrate that this configuration is a structural signature for a ubiquitous class of receptors in the plant kingdom. We show that EPR3 is promiscuous, suggesting that plants can monitor complex microbial communities though this class of receptors.


Assuntos
Lipopolissacarídeos/metabolismo , Lotus/microbiologia , Lotus/fisiologia , Mesorhizobium/metabolismo , Proteínas de Plantas/metabolismo , Sequência de Aminoácidos , Mesorhizobium/genética , Fixação de Nitrogênio/fisiologia , Proteínas de Plantas/genética , Dobramento de Proteína , Nódulos Radiculares de Plantas/microbiologia , Nódulos Radiculares de Plantas/fisiologia , Simbiose/fisiologia
18.
Sheng Wu Gong Cheng Xue Bao ; 36(7): 1431-1439, 2020 Jul 25.
Artigo em Chinês | MEDLINE | ID: mdl-32748601

RESUMO

The purpose of this study is to provide a culture for mouse bone marrow-derived macrophages (BMDM) and peritoneal macrophages (PM) and to characterize their molecular and cellular biology. The cell number and purity from the primary culture were assessed by cell counter and flow cytometry, respectively. Morphological features were evaluated by inverted microscope. Phagocytosis by macrophages was detected by the neutral red dye uptake assay. Phenotypic markers were analyzed by real-time fluorescent quantitative PCR. Our results show that the cell number was much higher from culture of BMDM than PM, while there was no significant difference regarding the percentage of F4/80+CD11b+ cells (98.30%±0.53% vs. 94.83%±1.42%; P>0.05). The proliferation rate of BMDM was significantly higher than PM in the presence of L929 cell conditioned medium, by using CCK-8 assay. However, PM appeared to adhere to the flask wall and extend earlier than BMDM. The phagocytosis capability of un-stimulated BMDM was significantly higher than PM, as well as lipopolysaccharide (LPS)-stimulated BMDM, except the BMDM stimulated by low dose LPS (0.1 µg/mL). Furthermore, Tnfα expression was significantly higher in un-stimulated BMDM than PM, while Arg1 and Ym1 mRNA expression were significantly lower than PM. The expression difference was persistent if stimulated by LPS+IFN-γ or IL-4. Our data indicate that bone marrow can get larger amounts of macrophages than peritoneal cavity. However, it should be aware that the molecular and cellular characteristics were different between these two culture systems.


Assuntos
Células da Medula Óssea , Macrófagos , Fagocitose , Animais , Células da Medula Óssea/fisiologia , Células Cultivadas , Meios de Cultivo Condicionados , Lipopolissacarídeos/metabolismo , Macrófagos/classificação , Macrófagos/fisiologia , Camundongos
19.
Phytochemistry ; 177: 112453, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32773084

RESUMO

Five previously undescribed lanostane-type triterpenoids, including two triterpenoids with a rearranged side chain (applanoic acids E and F), one C21 nortriterpenoid (16,17-dehydroapplanone E), as well as two highly oxygenated lanostane triterpenoids (methyl applaniate B and applanoic acid G), were isolated from the fruiting bodies of Ganoderma applanatum (Pers.) Pat. Their structures were elucidated on the basis of spectroscopic analysis, X-ray crystallography and ECD data. Applanoic acid E, 16,17-dehydroapplanone E, and methyl applaniate B showed inhibitory effects on the release of NO by LPS-induced BV-2 cells.


Assuntos
Ganoderma , Triterpenos , Carpóforos , Lipopolissacarídeos , Estrutura Molecular
20.
Nat Commun ; 11(1): 4142, 2020 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-32811831

RESUMO

Glycans are involved in various life processes and represent critical targets of biomedical developments. Nevertheless, the accessibility to long glycans with precise structures remains challenging. Here we report on the synthesis of glycans consisting of [→4)-α-Rha-(1 → 3)-ß-Man-(1 → ] repeating unit, which are relevant to the O-antigen of Bacteroides vulgatus, a common component of gut microbiota. The optimal combination of assembly strategy, protecting group arrangement, and glycosylation reaction has enabled us to synthesize up to a 128-mer glycan. The synthetic glycans are accurately characterized by advanced NMR and MS approaches, the 3D structures are defined, and their potent binding activity with human DC-SIGN, a receptor associated with the gut lymphoid tissue, is disclosed.


Assuntos
Bacteroides/química , Antígenos O/química , Polissacarídeos/síntese química , Bacteroides/imunologia , Bacteroides/metabolismo , Microbioma Gastrointestinal/imunologia , Humanos , Lipopolissacarídeos/química , Lipopolissacarídeos/imunologia , Espectroscopia de Ressonância Magnética , Antígenos O/imunologia , Antígenos O/metabolismo , Polissacarídeos/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
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