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1.
Entropy (Basel) ; 25(10)2023 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-37895519

RESUMO

As one of the most critical tasks in legal artificial intelligence, legal judgment prediction (LJP) has garnered growing attention, especially in the civil law system. However, current methods often overlook the challenge of imbalanced label distributions, treating each label with equal importance, which can lead the model to be biased toward labels with high frequency. In this paper, we propose a label-enhanced prototypical network (LPN) suitable for LJP, that adopts a strategy of uniform encoding and separate decoding. Specifically, LPN adopts a multi-scale convolutional neural network to uniformly encode case factual description to capture long-distance features of the document. At the decoding end, a prototypical network incorporating label semantic features is used to guide the learning of prototype representations of high-frequency and low-frequency labels, respectively. At the same time, we also propose a prototype-prototype loss to optimize the prototypical representation. We conduct extensive experiments on two real datasets and show that our proposed method effectively improves the performance of LJP, with an average F1 of 1.23% and 1.13% higher than the state-of-the-art model on two subtasks, respectively.

2.
Microbiol Spectr ; 10(6): e0115222, 2022 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-36354329

RESUMO

Rapid increase in resistance of Helicobacter pylori (H. pylori) has hindered antibiotics-based eradication efforts worldwide and raises the need for additional approaches. Here, we investigate the role of zinc-based compounds in inhibiting H. pylori growth and modulating antibiotic sensitivities, interrogate their downstream transcriptomic changes, and highlight the potential mechanism driving the observed effects. We showed that zinc acetate inhibited H. pylori growth and increased H. pylori sensitivity to levofloxacin. Transcriptomic profiling showed distinct gene expression patterns between zinc acetate treated groups versus controls. In particular, we independently replicated the association between zinc acetate treatment and increased ssrA expression. Knockdown of ssrA restored levofloxacin resistance to levels of the control group. In this study, we first demonstrated the role of zinc acetate in H. pylori growth and antibiotic sensitivities. Additionally, we explored the transcriptomic perturbations of zinc acetate followed by functional knockdown follow-up of differentially expressed ssrA, highlighting the role of tmRNA and trans-translation in H. pylori levofloxacin resistance. Our results provide alternative and complementary strategies for H. pylori treatment and shed light on the underlying mechanisms driving these effects. IMPORTANCE Helicobacter pylori (H. pylori) eradication plays an important role in gastric cancer prevention, but the antimicrobial resistance of H. pylori is fast becoming a growing concern. In this study, we investigated the role of zinc acetate in inhibiting H. pylori growth and modulating antibiotic sensitivities in vitro. Additionally, we explored the transcriptomic perturbations of zinc acetate followed by functional knockdown follow-up of differentially expressed ssrA, highlighting the role of tmRNA and trans-translation in H. pylori levofloxacin resistance. Our results open up a new horizon for the treatment of antibiotic-resistant H. pylori.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Humanos , Levofloxacino/farmacologia , Helicobacter pylori/genética , Acetato de Zinco/farmacologia , Claritromicina/farmacologia , Infecções por Helicobacter/tratamento farmacológico , Transcriptoma , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Testes de Sensibilidade Microbiana , Farmacorresistência Bacteriana/genética
3.
Int J Mol Sci ; 22(21)2021 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-34769438

RESUMO

Oleanolic acid (OA), asiatic acid (AA), and maslinic acid (MA) are ubiquitous isomeric triterpene phytochemicals with many pharmacological effects. To improve their application value, we used lipopolysaccharide (LPS) to induce RAW264.7 cells and studied the differences in the anti-inflammatory effects of the triterpenes according to their structural differences. MTT, Griess, and immunofluorescence assays, ELISA, flow cytometry, and Western blotting, were performed. The release of LPS-induced pro-inflammatory mediators, such as nitric oxide (NO), inducible nitric oxide synthase (iNOS), and interleukin (IL-6), was significantly inhibited by OA, AA, and MA at the same concentration, and AA and MA promoted the production of anti-inflammatory factor IL-10. OA, AA, and MA inhibited LPS-induced NF-κB nuclear translocation in RAW264.7 cells. OA and AA inhibited the phosphorylation of ERK1/2, P38, and JNK1/2 in LPS-stimulated RAW264.7 cells. Moreover, OA increased LPS-induced Nrf2 expression and decreased Keap1 expression in RAW264.7 cells. OA, AA, and MA inhibited LPS-stimulated intracellular reactive oxygen species (ROS) production and alleviated mitochondrial membrane potential depletion. Overall, our data suggested that OA, AA, and MA exhibited significant anti-inflammatory effects in vitro. In particular, OA and AA take effects through the MAPKs, NF-κB, and Nrf2 signaling pathways.


Assuntos
Anti-Inflamatórios/farmacologia , Hippophae/química , Mediadores da Inflamação/metabolismo , Lipopolissacarídeos/toxicidade , Macrófagos/efeitos dos fármacos , Triterpenos/farmacologia , Animais , Linhagem Celular , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Fator 2 Relacionado a NF-E2/metabolismo , NF-kappa B/metabolismo , Transdução de Sinais
4.
Eur J Pharmacol ; 909: 174413, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34391769

RESUMO

Ginsenoside Rg3, extracted from Panax ginseng C.A. Meyer, has been shown to possess neuroprotective properties. The present study aims to investigate the neuroprotective effects of ginsenoside Rg3 on rotenone-induced Parkinson's disease mice. Rotenone, a mitochondrial complex I inhibitor, leads to the augmentation of reactive oxygen species production in cells. Male C57/BL6 mice were intragastrically administered rotenone (30 mg/kg) and then treated with ginsenoside Rg3 (5, 10, or 20 mg/kg). Pole, rotarod, and open field tests were performed to evaluate motor function. Ginsenoside Rg3 decreased the climbing time in the pole test (p < 0.01), whereas it increased the latency in the rotarod test (p < 0.01) and the total distance (p < 0.01) and mean speed in the open field test (p < 0.01). Ginsenoside Rg3 treatment augmented the number of tyrosine hydroxylase-positive neurons in the substantia nigra (p < 0.01), mean density of tyrosine hydroxylase-positive nerve fibers (p < 0.01), and dopamine content (p < 0.01) in the striatum and reduced the reactive oxygen species level in the substantia nigra (p < 0.01). Glutathione cysteine ligase regulatory subunit and glutathione cysteine ligase modulatory subunit expression levels were elevated in the ginsenoside Rg3 groups. Ginsenoside Rg3 also improved motor function in rotenone-induced Parkinson's disease mice. The neuroprotective effects of ginsenoside Rg3 are at least partly associated with its anti-oxidative properties via regulation of glutathione cysteine ligase modulatory subunit and glutathione cysteine ligase regulatory subunit expression.


Assuntos
Antioxidantes/farmacologia , Ginsenosídeos/farmacologia , Fármacos Neuroprotetores/farmacologia , Doença de Parkinson Secundária/tratamento farmacológico , Animais , Antioxidantes/uso terapêutico , Modelos Animais de Doenças , Ginsenosídeos/uso terapêutico , Humanos , Masculino , Camundongos , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Fármacos Neuroprotetores/uso terapêutico , Estresse Oxidativo/efeitos dos fármacos , Doença de Parkinson Secundária/etiologia , Doença de Parkinson Secundária/patologia , Espécies Reativas de Oxigênio/metabolismo , Rotenona/toxicidade , Substância Negra/efeitos dos fármacos , Substância Negra/patologia
5.
Front Microbiol ; 12: 681911, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34093508

RESUMO

Efficacy of Helicobacter pylori (H. pylori) eradication therapy has declined due to rapid rises in antibiotic resistance. We investigated how increased temperature affected H. pylori (NCTC 11637) growth and its sensitivity to metronidazole in vitro. We performed transcriptomic profiling using RNA-sequencing to identify differentially expressed genes (DEGs) associated with increased temperature. Transcriptional pathways involved in temperature-driven metronidazole resistance changes were analyzed through bioinformatic and literature curation approaches. We showed that H. pylori growth was inhibited at 41°C and inhibition was more apparent with prolonged incubation. Resistance to metronidazole was also reduced-minimum inhibitory concentration for metronidazole decreased from > 256 µg/ml at 37°C to 8 µg/ml at 41°C after culturing for 3 days. RNA-sequencing results, which were highly concordant within treatment conditions, revealed more than one third of genes (583/1,552) to be differentially expressed at increased temperatures with similar proportions up and down-regulated. Quantitative real-time PCR validation for 8 out of 10 DEGs tested gave consistent direction in gene expression changes. We found enrichment for redox and oxygen radical pathways, highlighting a mechanistic pathway driving temperature-related metronidazole resistance. Independent literature review of published genes associated with metronidazole resistance revealed 46 gene candidates, 21 of which showed differential expression and 7 out of 9 DEGs associated with "redox" resistance pathways. Sanger sequencing did not detect any changes in genetic sequences for known resistance genes rdxA, frxA nor fdxB. Our findings suggest that temperature increase can inhibit the growth and reduce H. pylori resistance to metronidazole. Redox pathways are possible potential drivers in metronidazole resistance change induced by temperature. Our study provides insight into potential novel approaches in treating antibiotic resistant H. pylori.

6.
Microbiologyopen ; 9(9): e1102, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32666705

RESUMO

The diagnostic value of Helicobacter pylori stool antigen (HpSA) tests in elderly subjects remains unclear. The objective of this study was to assess the diagnostic accuracy of the immunochromatographic assay-based HpSA test in a male elderly cohort and identify factors affecting the accuracy. Data for asymptomatic elderly male citizens (≥65 years old) who received health checkups at the Chinese PLA General Hospital between July 2007 and November 2018 were collected. The diagnostic accuracy of the HpSA test was determined using the 13 C-urea breath test as a reference standard. Associations between baseline comorbidities and the accuracy of the HpSA test were analyzed. In total, 316 participants were enrolled, including 193 in the pre-treatment group (77.2 ± 7.8 years old) and 123 in the post-treatment group (78.7 ± 8.3 years old). The accuracy (91.5%, 91.2%, and 91.9%) and specificity (97.6%, 98.7%, and 96.0%) were high in all participants, pre- and post-treatment groups, respectively. However, sensitivities were only 68.7%, 65.1%, and 75.0%, respectively. In the pre-treatment group, constipation was associated with decreased sensitivity (p = 0.039), while colorectal polyps were associated with increased sensitivity (p = 0.010). Multivariate analysis indicated that constipation and colorectal polyps are independent factors for the sensitivity of HpSA in the pre-treatment group. The immunochromatographic assay-based HpSA test achieved high accuracy with high specificity but suboptimal sensitivity in the elderly male cohort. Constipation and colorectal polyps were negatively and positively associated with HpSA sensitivity, respectively, in the pre-treatment group.


Assuntos
Antígenos de Bactérias/análise , Fezes/microbiologia , Infecções por Helicobacter/diagnóstico , Helicobacter pylori/isolamento & purificação , Imunoensaio , Idoso , Idoso de 80 Anos ou mais , Testes Respiratórios , Comorbidade , Constipação Intestinal/complicações , Infecções por Helicobacter/complicações , Helicobacter pylori/imunologia , Humanos , Pólipos Intestinais/complicações , Masculino , Sensibilidade e Especificidade , Ureia/análise
7.
Toxicol In Vitro ; 65: 104823, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32147576

RESUMO

Rosmarinic acid (RA) is an extract that can be obtained from Lamiaceae herbs and the Boraginaceae family. This study aimed to evaluate the effect of RA on 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced dopaminergic neurotoxicity in zebrafish embryos. Embryos were challenged with MPTP and then were treated with RA or brusatol (a Nrf2 inhibitor). Locomotor activity of zebrafish was recorded using a video camera. The swimming distance was analyzed with SMART 3.0 software. Tyrosine hydroxylase (TH) immunohistochemistry, reactive oxygen species (ROS), glutathione (GSH), and malondialdehyde (MDA) contents were evaluated. The expressions of proteins in the DJ-1/Akt/Nrf2 signaling pathway were measured. The results showed that RA not only prevented MPTP-induced dopaminergic neuron loss, but also attenuated the deficit in locomotor behavior. RA attenuated the increases of ROS and MDA induced by MPTP. Treatment with RA augmented expression of glutamate cysteine ligase catalytic subunit, glutamate cysteine ligase modifier subunit, and GSH. Furthermore, RA increased the expression of DJ-1, p-Akt, Nuclear-Nrf2, HO-1 and inhibited the expression of PTEN. Brusatol partially abolished the neuroprotective effect of RA in MPTP-induced Parkinson's disease (PD) model of zebrafish embryos. The results of this study indicate that RA exerts neuroprotective effects on MPTP-induced neurotoxicity in dopaminergic neurons of a zebrafish PD model. The mechanism underlying the effects of RA is associated with promotion of antioxidant gene expression via regulation of the DJ-1/Akt/Nrf2 signaling pathway.


Assuntos
Cinamatos/farmacologia , Depsídeos/farmacologia , Intoxicação por MPTP/tratamento farmacológico , Fármacos Neuroprotetores/farmacologia , Animais , Neurônios Dopaminérgicos/efeitos dos fármacos , Embrião não Mamífero , Glutationa/metabolismo , Locomoção/efeitos dos fármacos , Intoxicação por MPTP/metabolismo , Intoxicação por MPTP/fisiopatologia , Malondialdeído/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Peixe-Zebra , Ácido Rosmarínico
8.
Dalton Trans ; 49(7): 2112-2120, 2020 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-31993596

RESUMO

A simple coprecipitation route followed by a calcination process was developed to prepare 2D hierarchical Zn3(VO4)2 porous networks formed by the crosslinkage of monolayered nanoparticles. As a promising anode for lithium ion batteries, the electrochemical performance of Zn3(VO4)2 was investigated. At a current density of 1.0 A g-1, the Zn3(VO4)2 porous networks could register a high reversible discharge capacity of 773 mA h g-1 and the capacity retention was 94% after 700 cycles. Moreover, a remarkable reversible discharge capacity of 445 mA h g-1 was achieved at a current density of 5 A g-1 after 1200 cycles. Even at a higher current density of 10.0 A g-1, a high reversible capacity of 527 mA h g-1 could be delivered, which still remained at 163 mA h g-1 after 1200 cycles. This superior performance is attributed to the unique 2D porous networks with a stable structure. This work shows a new avenue for facile, cheap, green, and mass production of zinc vanadate oxides with 2D porous hierarchical networks for next-generation energy conversion and storage devices.

9.
Molecules ; 25(1)2019 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-31861877

RESUMO

Limonene is a monoterpenoid compound, which is founded in a lot of plants' essential oils with good antibacterial activity against food-borne pathogens, but it has an ambiguous antimicrobial susceptibility and mechanism against Listeria monocytogenes (L. monocytogenes). In this study, the antimicrobial susceptibility of Limonene to L. monocytogenes was studied, and some new sights regarding its antibacterial mechanism were further explored. Scanning electron microscopy (SEM) verified that limonene caused the destruction of the cell integrity and wall structure of L. monocytogenes. The increase in conductivity and the leakage of intracellular biomacromolecules (nucleic acids and proteins) confirmed that limonene had an obvious effect on cell membrane permeability. The results of Propidium Iodide (PI) fluorescence staining were consistent with the results of the conductivity measurements. This indicated that limonene treatment caused damage to the L. monocytogenes cell membrane. Furthermore, the decrease in ATP content, ATPase (Na+K+-ATPase, Ca2+-ATPase) activity and respiratory chain complex activity indicated that limonene could hinder ATP synthesis by inhibiting the activity of the respiratory complex and ATPase. Finally, differential expression of proteins in the respiratory chain confirmed that limonene affected respiration and energy metabolism by inhibiting the function of the respiratory chain complex.


Assuntos
Antibacterianos/farmacologia , Permeabilidade da Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Limoneno/farmacologia , Listeria monocytogenes/metabolismo , Óleos Voláteis/química , Antibacterianos/química , Limoneno/química
10.
Nephrology (Carlton) ; 24(9): 983-991, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31314137

RESUMO

AIM: Protease-activated receptor 2 (PAR2) has been implicated in the development of renal inflammation and fibrosis. In particular, activation of PAR2 in cultured tubular epithelial cells induces extracellular signal-regulated kinase signalling and secretion of fibronectin, C-C Motif Chemokine Ligand 2 (CCL2) and transforming growth factor-ß1 (TGF-ß1), suggesting a role in tubulointerstitial inflammation and fibrosis. We tested this hypothesis in unilateral ureteric obstruction (UUO) in which ongoing tubular epithelial cell damage drives tubulointerstitial inflammation and fibrosis. METHODS: Unilateral ureteric obstruction surgery was performed in groups (n = 9/10) of Par2-/- and wild type (WT) littermate mice which were killed 7 days later. Non-experimental mice were controls. RESULTS: Wild type mice exhibited a 5-fold increase in Par2 messenger RNA (mRNA) levels in the UUO kidney. In situ hybridization localized Par2 mRNA expression to tubular epithelial cells in normal kidney, with a marked increase in Par2 mRNA expression by tubular cells, including damaged tubular cells, in WT UUO kidney. Tubular damage (tubular dilation, increased KIM-1 and decreased α-Klotho expression) and tubular signalling (extracellular signal-regulated kinase phosphorylation) seen in WT UUO were not altered in Par2-/- UUO. In addition, macrophage infiltration, up-regulation of M1 (NOS2) and M2 (CD206) macrophage markers, and up-regulation of pro-inflammatory molecules (tumour necrosis factor, CCL2, interleukin-36α) in WT UUO kidney were unchanged in Par2-/- UUO. Finally, the accumulation of α-SMA+ myofibroblasts, deposition of collagen IV and expression of pro-fibrotic factors (CTGF, TGF-ß1) were not different between WT and Par2-/- UUO mice. CONCLUSION: Protease-activated receptor 2 expression is substantially up-regulated in tubular epithelial cells in the obstructed kidney, but this does not contribute to the development of tubular damage, renal inflammation or fibrosis.


Assuntos
Túbulos Renais/metabolismo , Nefrite Intersticial/etiologia , Receptor PAR-2/metabolismo , Obstrução Ureteral/complicações , Animais , Modelos Animais de Doenças , Fibrose , Regulação da Expressão Gênica , Túbulos Renais/patologia , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Nefrite Intersticial/genética , Nefrite Intersticial/metabolismo , Nefrite Intersticial/patologia , Receptor PAR-2/deficiência , Receptor PAR-2/genética , Transdução de Sinais , Obstrução Ureteral/genética , Obstrução Ureteral/metabolismo , Obstrução Ureteral/patologia
11.
Clin Exp Pharmacol Physiol ; 46(5): 456-464, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30811624

RESUMO

Glomerular crescent formation is a hallmark of rapidly progressive forms of glomerulonephritis. Thrombosis and macrophage infiltration are features of crescent formation in human and experimental kidney disease. Protease-activated receptor-2 (PAR-2) is a G-protein coupled receptor that links coagulation and inflammation. This study investigated whether pharmacological inhibition of PAR-2 can suppress glomerular crescent formation in rat nephrotoxic serum nephritis (NTN). Disease was induced in Wistar Kyoto rats by immunisation with sheep IgG followed by administration of sheep nephrotoxic serum. Rats (n = 8/group) received the PAR-2 antagonist (GB88, 10 mg/kg/p.o.), vehicle or no treatment starting 3 days before nephrotoxic serum injection and continuing until day 14. Vehicle and untreated rats developed thrombosis and macrophage infiltration in the glomerular tuft and Bowman's space in conjunction with prominent crescent formation. Activation of JNK signalling and proliferation in parietal epithelial cells was associated with crescent formation. GB88 treatment significantly reduced crescent formation with a substantial reduction in glomerular thrombosis, reduced macrophage infiltration in Bowman's space, and reduced activation of parietal epithelial cells. However, GB88 did not protect against the development of proteinuria, renal function impairment, inflammation or tubular cell damage in the NTN model. In conclusion, PAR-2 plays a specific role in glomerular crescent formation by promoting glomerular thrombosis, macrophage accumulation in Bowman's space and activation of parietal epithelial cells.


Assuntos
Glomérulos Renais/efeitos dos fármacos , Glomérulos Renais/patologia , Nefrite/tratamento farmacológico , Receptor PAR-2/antagonistas & inibidores , Animais , Modelos Animais de Doenças , Glomérulos Renais/metabolismo , Masculino , Nefrite/metabolismo , Nefrite/patologia , Oligopeptídeos/farmacologia , Oligopeptídeos/uso terapêutico , Ratos , Ratos Wistar
12.
J Cell Mol Med ; 22(9): 4522-4533, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29998485

RESUMO

Activation of p38 mitogen-activated protein kinase (MAPK) and c-Jun amino terminal kinase (JNK) is prominent in human crescentic glomerulonephritis. p38 and JNK inhibitors suppress crescentic disease in animal models; however, the upstream mechanisms inducing activation of these kinases in crescentic glomerulonephritis are unknown. We investigated the hypothesis that apoptosis signal-regulating kinase 1 (ASK1/MAP3K5) promote p38/JNK activation and renal injury in models of nephrotoxic serum nephritis (NTN); acute glomerular injury in SD rats, and crescentic disease in WKY rats. Treatment with the selective ASK1 inhibitor, GS-444217 or vehicle began 1 hour before nephrotoxic serum injection and continued until animals were killed on day 1 (SD rats) or 14 (WKY rats). NTN resulted in phosphorylation (activation) of p38 and c-Jun in both models which was substantially reduced by ASK1 inhibitor treatment. In SD rats, GS-444217 prevented proteinuria and glomerular thrombosis with suppression of macrophage activation on day 1 NTN. In WKY rats, GS-444217 reduced crescent formation, prevented renal impairment and reduced proteinuria on day 14 NTN. Macrophage activation, T-cell infiltration and renal fibrosis were also reduced by GS-444217. In conclusion, GS-444217 treatment inhibited p38/JNK activation and development of renal injury in rat NTN. ASK1 inhibitors may have therapeutic potential in rapidly progressive glomerulonephritis.


Assuntos
Glomerulonefrite/tratamento farmacológico , Proteínas Quinases JNK Ativadas por Mitógeno/genética , MAP Quinase Quinase Quinase 5/genética , Inibidores de Proteínas Quinases/farmacologia , Proteinúria/prevenção & controle , Trombose/prevenção & controle , Proteínas Quinases p38 Ativadas por Mitógeno/genética , Animais , Movimento Celular/efeitos dos fármacos , Modelos Animais de Doenças , Feminino , Fibrose , Regulação da Expressão Gênica , Glomerulonefrite/genética , Glomerulonefrite/imunologia , Glomerulonefrite/patologia , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases JNK Ativadas por Mitógeno/imunologia , Glomérulos Renais/efeitos dos fármacos , Glomérulos Renais/imunologia , Glomérulos Renais/patologia , MAP Quinase Quinase Quinase 5/antagonistas & inibidores , MAP Quinase Quinase Quinase 5/imunologia , Ativação de Macrófagos/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Macrófagos/patologia , Fosforilação/efeitos dos fármacos , Proteinúria/genética , Proteinúria/imunologia , Proteinúria/patologia , Ratos , Ratos Endogâmicos WKY , Ratos Sprague-Dawley , Transdução de Sinais , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Linfócitos T/patologia , Trombose/genética , Trombose/imunologia , Trombose/patologia , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases p38 Ativadas por Mitógeno/imunologia
13.
Int J Immunopathol Pharmacol ; 32: 2058738418783404, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29923438

RESUMO

Non-selective inhibitors of spleen tyrosine kinase (SYK) efficiently suppress disease in T cell-dependent models of crescentic glomerulonephritis. However, the therapeutic potential of selective SYK inhibitors in this disease has not been established. In addition, we lack knowledge regarding SYK expression in non-myeloid cells in glomerulonephritis. We addressed these two issues in a rat model of nephrotoxic serum nephritis (NTN) using a SYK inhibitor, GS-492429. Disease was induced in Sprague-Dawley rats (Study 1) or Wistar-Kyoto (WKY) rats (Study 2) by immunization with sheep IgG and administration of sheep anti-rat nephrotoxic serum. Animals were untreated or received GS-492429 (30 mg/kg/bid) or vehicle treatment from 2 h before nephrotoxic serum injection until being killed 3 or 24 h later (Study 1) or 14 days later (Study 2). Two-colour confocal microscopy found that SYK expression in NTN kidney was restricted to myeloid cells and platelets, with no evidence of SYK expression by T cells, mesangial cells, podocytes or tubular epithelial cells. In Study 1, GS-492429 treatment significantly reduced glomerular neutrophil and macrophage infiltration, with protection from glomerular thrombosis and proteinuria. In Study 2, GS-492429 treatment reduced glomerular crescent formation by 70% on day 14 NTN in conjunction with reduced glomerular thrombosis, glomerulosclerosis and tubular damage. This was accompanied by a marked reduction in markers of inflammation (CCL2, TNF-α, NOS2, MMP-12). Importantly, the protective effects of GS-492429 were independent of T cell infiltration and activation and independent of JAK/STAT3 signalling. In conclusion, this study demonstrates that a SYK inhibitor can suppress the development of crescentic glomerulonephritis through effects upon myeloid cells and platelets.


Assuntos
Glomerulonefrite/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Quinase Syk/antagonistas & inibidores , Animais , Modelos Animais de Doenças , Feminino , Glomerulonefrite/enzimologia , Glomerulonefrite/patologia , Testes de Função Renal , Glomérulos Renais/efeitos dos fármacos , Glomérulos Renais/enzimologia , Glomérulos Renais/patologia , Masculino , Ratos Endogâmicos WKY , Ratos Sprague-Dawley
14.
Clin Exp Pharmacol Physiol ; 45(3): 241-249, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29124787

RESUMO

Tubular epithelial cells take up and degrade plasma albumin filtered by the glomerulus. Tubular damage resulting in reduced albumin uptake or degradation has been suggested as one mechanism contributing to albuminuria in kidney disease. This study investigated whether tubular albumin uptake or degradation is altered in acute and chronic glomerular disease. Mouse models of acute glomerular injury (anti-GBM disease and LPS-induced albuminuria) and chronic disease (streptozotocin-induced diabetes and db/db mice) were examined. Mice were injected intravenously with Alexa-albumin plus DQ-albumin and killed 20 minutes later. Tubular uptake of albumin (Alexa-albumin) and albumin degradation (Dye Quenched (DQ)-albumin) was assessed in tissue sections via confocal microscopy. Tubular uptake of Alexa-albumin in the models of diabetic nephropathy was not different to normal mice. However, the fluorescence signal resulting from degradation of DQ-albumin was significantly reduced in db/db mice, and the ratio of degraded to intact albumin was reduced in both models. The ratio of degraded to intact albumin in tubules was also reduced in the anti-GBM model. In the LPS model, both tubular uptake and degradation of albumin were significantly reduced, with a substantial reduction in the ratio of degraded to intact albumin in tubules. LPS stimulation of cultured tubular epithelial cells inhibited albumin uptake, indicating a direct role for LPS in modifying tubular handling of albumin. In conclusion, reduced degradation of filtered albumin in the proximal tubule is a common feature of glomerular diseases. This may be a general mechanism whereby tubular dysfunction contributes to the development of albuminuria.


Assuntos
Injúria Renal Aguda/metabolismo , Nefropatias Diabéticas/metabolismo , Túbulos Renais/fisiologia , Insuficiência Renal Crônica/metabolismo , Albumina Sérica/metabolismo , Animais , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Tipo 1 , Diabetes Mellitus Tipo 2 , Lipopolissacarídeos , Camundongos , Camundongos Endogâmicos NOD
15.
Epigenetics ; 12(7): 575-583, 2017 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-28678648

RESUMO

Colorectal cancer (CRC) is the third most common malignancy and the fourth most common cause of cancer related death worldwide. This study was designed to find tumor suppressors involved in CRC development by performing RNA-seq. Eight CRC cell lines and 130 cases of primary CRC samples were used. RNA-seq, methylation-specific PCR (MSP), flow cytometry, transwell assays, and a xenograft mouse model were used. Reduction of TMEM176A expression was confirmed in human CRC cells by RNA-seq. TMEM176A was expressed in LS180 and SW620 cells, loss of TMEM176A expression was observed in LOVO, HCT116, RKO, and DLD1 cells, and reduced TMEM176A expression was found in HT29 and SW480 cells. Unmethylation of the TMEM176A promoter was found in LS180 and SW620 cells, whereas complete methylation was found in LOVO, HCT116, RKO, and DLD1 cells, and partial methylation was found in HT29 and SW480 cells. Promoter region methylation correlated with loss of/reduced expression of TMEM176A. Re-expression of TMEM176A was induced by 5-aza-2'-deoxycytidine. TMEM176A was methylated in 50.77% of primary colorectal cancers. Methylation of TMEM176A was associated with tumor metastasis (P<0.05) and was an independent prognostic factor for 5-year overall survival (OS) according to Cox proportional hazards model analysis (P<0.05). TMEM176A induced apoptosis and inhibited cell migration and invasion in CRC cells. TMEM176A suppressed CRC cell growth both in vitro and in vivo. Our results suggest that expression of TMEM176A is regulated by promoter region methylation. TMEM176A methylation is an independent prognostic marker for 5-year OS in CRC, and may act as a tumor suppressor in CRC.


Assuntos
Biomarcadores Tumorais/genética , Carcinoma/genética , Neoplasias Colorretais/genética , Metilação de DNA , Proteínas de Membrana/genética , Animais , Biomarcadores Tumorais/metabolismo , Carcinoma/patologia , Neoplasias Colorretais/patologia , Feminino , Células HCT116 , Células HT29 , Humanos , Masculino , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , Regiões Promotoras Genéticas
16.
Transplantation ; 101(8): e240-e248, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28594748

RESUMO

BACKGROUND: Organ transplantation into sensitized patients with preexisting donor-specific antibodies (DSA) is very challenging. Spleen tyrosine kinase (Syk) promotes leukocyte recruitment and activation via signaling through various cell surface receptors. We investigated whether a selective Syk inhibitor (GS-492429) could suppress antibody-mediated rejection (AMR) in a rat model of AMR in sensitized recipients. METHODS: Recipient Lewis rats (RT1) were immunized with donor (Dark Agouti, RT1) spleen cells (day -5). Recipients underwent bilateral nephrectomy and orthotopic renal transplantation (day 0). Cellular rejection was minimized by tacrolimus treatment from day -1. Groups received GS-492429 (30 mg/kg, twice a day) (n = 11) or vehicle (n = 12) from 1 hour before transplantation until being killed on day 3. RESULTS: Vehicle-treated recipients developed graft dysfunction on day 1 which rapidly worsened by day 3. Histology showed severe damage (thrombosis, acute tubular injury, capillaritis) and infiltration of many Syk leukocytes. GS-492429 did not affect graft dysfunction on day 1, but treatment reduced allograft damage and prevented the rapid deterioration of graft function on day 3. GS-492429 reduced the prominent macrophage infiltrate and reduced the M1 proinflammatory response. Neutrophil and NK cell infiltration and capillary thrombosis were also significantly reduced by GS-492429 treatment. Serum DSA levels and the deposition of IgG and C4d in the allograft were equivalent in the 2 groups. CONCLUSIONS: Treatment with a Syk inhibitor significantly reduced renal allograft injury in a model of severe antibody-mediated damage in highly sensitized recipients. Further studies are warranted to determine whether Syk inhibition is a potential adjunctive treatment in clinical AMR.


Assuntos
Anticorpos/imunologia , Rejeição de Enxerto/prevenção & controle , Transplante de Rim/efeitos adversos , Inibidores de Proteínas Quinases/farmacologia , Quinase Syk/antagonistas & inibidores , Transplantados , Doença Aguda , Animais , Western Blotting , Modelos Animais de Doenças , Rejeição de Enxerto/enzimologia , Rejeição de Enxerto/imunologia , Ratos , Ratos Endogâmicos Lew , Transdução de Sinais , Quinase Syk/metabolismo , Transplante Homólogo
17.
Sci Total Environ ; 586: 255-264, 2017 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-28187942

RESUMO

Three indoor (residential home, dormitory, and office) and one outdoor concentrations of PM2.5-bound Polycyclic aromatic hydrocarbons (PAHs) were analyzed in Beijing across four seasons. The highest and lowest concentration of total PAHs for outdoor appeared in winter and in summer with averages of 200.1 and 9.1ng/m3 respectively. The seasonal variations of total PAHs in three indoor sites were the same as outdoor. The correlation analysis between the indoor and outdoor samples showed that the annual mean I/O ratios of total PAHs in the three sites were lower than 1. Source apportionment showed vehicle exhaust, coal combustion, and biomass burning were the major contributors of indoor and outdoor PM2.5-bound PAHs. Indoor source, such as camphor pollution, was identified in the dormitory, while camphor pollution and cooking sources were identified in the residential home. The annual averages of Benzo[a]pyrene equivalent concentration (BaPeq) were 7.6, 7.8, 7.7 and 12.7ng/m3 for the dormitory, office, residential home and outdoor samples respectively, far higher than the annual limit of 1ng/m3 regulated by European Commission. Life lung cancer risk (LLCR) in four sites across four seasons were over the acceptable cancer risk level, showing the cancer risk were at a high level in both indoor and outdoor sites in Beijing, and its level in indoor sites was much lower than in the outdoor site. The health risk assessment indicated the level of PAHs cancer risk on human for three indoor sites were similar. The results call for the development of more stringent control measures to reduce PAHs emissions.

18.
J Pathol ; 238(1): 10-20, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26251216

RESUMO

Antibody-dependent activation of myeloid cells within the glomerulus plays a central role in rapidly progressive forms of glomerulonephritis. The spleen tyrosine kinase (Syk) is expressed by all leukocytes, except mature T cells, and is required for signalling via the B-cell receptor, Fc receptors, and some integrins. Syk has been proposed as a therapeutic target in glomerulonephritis. However, little is known of Syk activation in human kidney disease, while studies in experimental glomerulonephritis using non-selective Syk inhibitors require validation via conditional gene deletion. The current study addressed both of these important points. Syk activation (Tyr(525/526) phosphorylation) was examined in a cohort of 96 patients with different glomerulonephritides. Syk activation was evident in infiltrating leukocytes, mainly neutrophils and macrophages, in 36/40 cases of rapidly progressive glomerulonephritis. In contrast, non-proliferative diseases showed little or no Syk activation. Glomerular and interstitial cells exhibiting Syk activation correlated with renal function and systemic inflammation. Next, we examined mice with conditional Syk gene deletion in myeloid cells (Syk(My) ) versus Syk(f/f) littermate controls in nephrotoxic serum nephritis - a model of rapidly progressive glomerulonephritis. Control Syk(f/f) mice featured a transient neutrophil influx at 3 h and severe disease on day 9 of nephrotoxic serum nephritis, with crescent formation, macrophage infiltration, inflammation, kidney fibrosis, and renal dysfunction. In contrast, Syk(My) mice had significantly reduced neutrophil and macrophage infiltration despite equivalent glomerular deposition of humoral reactants. Syk(My) mice exhibited reduced crescent formation, inflammation, and fibrosis, with improved renal function on day 9 of nephrotoxic serum nephritis. In conclusion, Syk activation is prominent in infiltrating myeloid cells in human rapidly progressive glomerulonephritis, and functional studies demonstrate that Syk deletion in myeloid cells is protective in mouse nephrotoxic serum nephritis.


Assuntos
Ativação Enzimática/fisiologia , Glomerulonefrite/enzimologia , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Células Mieloides/enzimologia , Proteínas Tirosina Quinases/metabolismo , Animais , Western Blotting , Citometria de Fluxo , Imunofluorescência , Técnicas de Inativação de Genes , Glomerulonefrite/patologia , Humanos , Imuno-Histoquímica , Camundongos , Camundongos Endogâmicos C57BL , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Quinase Syk
19.
PLoS One ; 10(12): e0145666, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26700873

RESUMO

BACKGROUND/AIM: Steroidal mineralocorticoid receptor antagonists (MRAs) are effective in the treatment of kidney disease; however, the side effect of hyperkalaemia, particularly in the context of renal impairment, is a major limitation to their clinical use. Recently developed non-steroidal MRAs have distinct characteristics suggesting that they may be superior to steroidal MRAs. Therefore, we explored the benefits of a non-steroidal MRA in a model of rapidly progressive glomerulonephritis. METHODS: Accelerated anti-glomerular basement membrane (GBM) glomerulonephritis was induced in groups of C57BL/6J mice which received no treatment, vehicle or a non-steroidal MRA (BR-4628, 5mg/kg/bid) from day 0 until being killed on day 15 of disease. Mice were examined for renal injury. RESULTS: Mice with anti-GBM glomerulonephritis which received no treatment or vehicle developed similar disease with severe albuminuria, impaired renal function, glomerular tuft damage and crescents in 40% of glomeruli. In comparison, mice which received BR-4628 displayed similar albuminuria, but had improved renal function, reduced severity of glomerular tuft lesions and a 50% reduction in crescents. The protection seen in BR-4628 treated mice was associated with a marked reduction in glomerular macrophages and T-cells and reduced kidney gene expression of proinflammatory (CCL2, TNF-α, IFN-γ) and profibrotic molecules (collagen I, fibronectin). In addition, treatment with BR-4626 did not cause hyperkalaemia or increase urine Na+/K+ excretion (a marker of tubular dysfunction). CONCLUSIONS: The non-steroidal MRA (BR-4628) provided substantial suppression of mouse crescentic glomerulonephritis without causing tubular dysfunction. This finding warrants further investigation of non-steroidal MRAs as a therapy for inflammatory kidney diseases.


Assuntos
Cromonas/farmacologia , Di-Hidropiridinas/farmacologia , Glomerulonefrite/prevenção & controle , Antagonistas de Receptores de Mineralocorticoides/farmacologia , Animais , Células Cultivadas , Feminino , Glomerulonefrite/metabolismo , Glomerulonefrite/patologia , Técnicas Imunoenzimáticas , Testes de Função Renal , Glomérulos Renais/efeitos dos fármacos , Glomérulos Renais/metabolismo , Glomérulos Renais/patologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Macrófagos/patologia , Camundongos , Camundongos Endogâmicos C57BL , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa
20.
Diabetes ; 64(11): 3903-13, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26180085

RESUMO

p38 mitogen-activated protein kinase (MAPK) signaling promotes diabetic kidney injury. Apoptosis signal-regulating kinase (ASK)1 is one of the upstream kinases in the p38 MAPK-signaling pathway, which is activated by inflammation and oxidative stress, suggesting a possible role for ASK1 in diabetic nephropathy. In this study, we examined whether a selective ASK1 inhibitor can prevent the induction and progression of diabetic nephropathy in mice. Diabetes was induced in hypertensive endothelial nitric oxide synthase (Nos3)-deficient mice by five low-dose streptozotocin (STZ) injections. Groups of diabetic Nos3(-/-) mice received ASK1 inhibitor (GS-444217 delivered in chow) as an early intervention (2-8 weeks after STZ) or late intervention (weeks 8-15 after STZ). Control diabetic and nondiabetic Nos3(-/-) mice received normal chow. Treatment with GS-444217 abrogated p38 MAPK activation in diabetic kidneys but had no effect upon hypertension in Nos3(-/-) mice. Early intervention with GS-444217 significantly inhibited diabetic glomerulosclerosis and reduced renal dysfunction but had no effect on the development of albuminuria. Late intervention with GS-444217 improved renal function and halted the progression of glomerulosclerosis, renal inflammation, and tubular injury despite having no effect on established albuminuria. In conclusion, this study identifies ASK1 as a new therapeutic target in diabetic nephropathy to reduce renal inflammation and fibrosis independent of blood pressure control.


Assuntos
Diabetes Mellitus Experimental/patologia , Nefropatias Diabéticas/tratamento farmacológico , Inibidores Enzimáticos/uso terapêutico , MAP Quinase Quinase Quinase 5/antagonistas & inibidores , Óxido Nítrico Sintase Tipo III/metabolismo , Animais , Pressão Sanguínea/efeitos dos fármacos , Diabetes Mellitus Experimental/metabolismo , Nefropatias Diabéticas/metabolismo , Nefropatias Diabéticas/patologia , Progressão da Doença , Inibidores Enzimáticos/farmacologia , Masculino , Camundongos , Camundongos Knockout , Óxido Nítrico Sintase Tipo III/genética , Transdução de Sinais/efeitos dos fármacos
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