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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.
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
3.
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
4.
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
5.
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
6.
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
7.
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
8.
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
9.
Int J Exp Pathol ; 96(1): 54-62, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25529862

RESUMO

Kidney allografts induce strong T-cell and antibody responses which mediate acute rejection. Spleen tyrosine kinase (Syk) is expressed by most leucocytes, except mature T cells, and is involved in intracellular signalling following activation of the Fcγ-receptor, B-cell receptor and some integrins. A role for Syk signalling has been established in antibody-dependent native kidney disease, but little is known of Syk in acute renal allograft rejection. Sprague-Dawley rats underwent bilateral nephrectomy and received an orthotopic Wistar renal allograft. Recipient rats were treated with a Syk inhibitor (CC0482417, 30 mg/kg/bid), or vehicle, from 1 h before surgery until being killed 5 days later. Vehicle-treated recipients developed severe allograft failure with marked histologic damage in association with dense leucocyte infiltration (T cells, macrophages, neutrophils and NK cells) and deposition of IgM, IgG and C3. Immunostaining identified Syk expression by many infiltrating leucocytes. CC0482417 treatment significantly improved allograft function and reduced histologic damage, although allograft injury was still clearly evident. CC0482417 failed to prevent T-cell infiltration and activation within the allograft. However, CC0482417 significantly attenuated acute tubular necrosis, infiltration of macrophages and neutrophils and thrombosis of peritubular capillaries. In conclusion, this study identifies a role for Syk in acute renal allograft rejection. Syk inhibition may be a useful addition to T-cell-based immunotherapy in renal transplantation.


Assuntos
Rejeição de Enxerto/enzimologia , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Transplante de Rim/efeitos adversos , Rim/enzimologia , Rim/cirurgia , Proteínas Tirosina Quinases/metabolismo , Doença Aguda , Aloenxertos , Animais , Quimiotaxia , Modelos Animais de Doenças , Rejeição de Enxerto/imunologia , Rejeição de Enxerto/patologia , Rejeição de Enxerto/prevenção & controle , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Rim/efeitos dos fármacos , Rim/imunologia , Rim/patologia , Macrófagos/efeitos dos fármacos , Macrófagos/enzimologia , Macrófagos/imunologia , Inibidores de Proteínas Quinases/farmacologia , Proteínas Tirosina Quinases/antagonistas & inibidores , Ratos Sprague-Dawley , Ratos Wistar , Transdução de Sinais , Quinase Syk , Linfócitos T/efeitos dos fármacos , Linfócitos T/enzimologia , Linfócitos T/imunologia , Fatores de Tempo
10.
J Am Soc Nephrol ; 25(10): 2231-40, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24700867

RESUMO

Clinical and experimental studies have shown that mineralocorticoid receptor (MR) antagonists substantially reduce kidney injury. However, the specific cellular targets and mechanisms by which MR antagonists protect against kidney injury must be identified. We used conditional gene deletion of MR signaling in myeloid cells (MR(flox/flox) LysM(Cre) mice; MyMRKO) or podocytes (MR(flox/flox) Pod(Cre) mice; PodMRKO) to establish the role of MR in these cell types in the development of mouse GN. Accelerated anti-glomerular basement membrane GN was examined in groups of mice: MyMRKO, PodMRKO, wild-type (WT) littermates, and WT mice receiving eplerenone (100 mg/kg twice a day; EPL-treated). At day 15 of disease, WT mice had glomerular crescents (37%±5%), severe proteinuria, and a 6-fold increase in serum cystatin-C. MyMRKO, PodMRKO, and EPL-treated mice with GN displayed proteinuria similar to that in these disease controls. However, MyMRKO and EPL-treated groups had a 35% reduction in serum cystatin-C levels and reduced crescent numbers compared with WT mice, whereas PodMRKO mice were not protected. The protection observed in MyMRKO mice appeared to result predominantly from reduced recruitment of macrophages and neutrophils into the inflamed kidney. Suppression of kidney leukocyte accumulation in MyMRKO mice correlated with reductions in gene expression of proinflammatory molecules (TNF-α, inducible nitric oxide synthase, chemokine (C-C motif) ligand 2, matrix metalloproteinase-12), tubular damage, and renal fibrosis and was similar in EPL-treated mice. In conclusion, MR signaling in myeloid cells, but not podocytes, contributes to the progression of renal injury in mouse GN, and myeloid deficiency of MR provides protection similar to eplerenone in this disease.


Assuntos
Doença Antimembrana Basal Glomerular/etiologia , Células Mieloides/metabolismo , Podócitos/metabolismo , Receptores de Mineralocorticoides/metabolismo , Animais , Doença Antimembrana Basal Glomerular/metabolismo , Modelos Animais de Doenças , Feminino , Contagem de Leucócitos , Camundongos Endogâmicos C57BL , Equilíbrio Hidroeletrolítico
11.
Am J Physiol Renal Physiol ; 304(8): F1043-53, 2013 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-23408165

RESUMO

The ability of macrophages to cause acute inflammatory glomerular injury is well-established; however, the role of macrophages in the fibrotic phase of chronic kidney disease remains poorly understood. This study examined the role of macrophages in the fibrotic phase (days 14 to 35) of established crescentic glomerulonephritis. Nephrotoxic serum nephritis (NTN) was induced in groups of eight Wistar-Kyoto rats that were given a selective c-fms kinase inhibitor, fms-I, or vehicle alone from day 14 until being killed on day 35. Rats killed on day 14 NTN had pronounced macrophage infiltration with glomerular damage, fibrocellular crescents in 50% of glomeruli, tubulointerstitial damage, heavy proteinuria, and renal dysfunction. Glomerulosclerosis was more severe by day 35 in vehicle-treated rats, as was periglomerular and interstitial fibrosis, while proteinuria and renal dysfunction continued unabated and some parameters of tubular damage worsened. During the day 14-to-35 period, glomerular and interstitial macrophage infiltration decreased with an apparent change from a proinflammatory M1 phenotype to an alternatively activated M2 phenotype. Treatment with fms-I over days 14 to 35 selectively reduced blood monocyte numbers and abrogated glomerular and interstitial macrophage infiltration. This resulted in improved renal function, significantly reduced glomerular and interstitial fibrosis, and protection against further peritubular capillary loss. However, sustained proteinuria, tubular damage, and interstitial T cell infiltration and activation were unaffected. In conclusion, this study demonstrates that macrophages contribute to renal dysfunction and tissue damage in established crescentic glomerulonephritis as it progresses from the acute inflammatory to a chronic fibrotic phase.


Assuntos
Glomerulonefrite/patologia , Macrófagos Peritoneais/patologia , Insuficiência Renal Crônica/patologia , Animais , Colágeno Tipo I/genética , Progressão da Doença , Fibrose/imunologia , Fibrose/patologia , Glomerulonefrite/imunologia , Imunofenotipagem , Macrófagos Peritoneais/imunologia , Masculino , Miofibroblastos/imunologia , Miofibroblastos/patologia , Inibidor 1 de Ativador de Plasminogênio/genética , Proteinúria/imunologia , Proteinúria/patologia , RNA Mensageiro/metabolismo , Ratos , Ratos Endogâmicos WKY , Insuficiência Renal Crônica/imunologia , Fator de Crescimento Transformador beta1/genética
12.
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
13.
Lab Invest ; 91(7): 978-91, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21519331

RESUMO

Depletion and adoptive transfer studies have demonstrated that macrophages induce glomerular lesions in experimental anti-glomerular basement membrane (anti-GBM) glomerulonephritis. However, there is no current therapeutic strategy that can rapidly and selectively remove these cells from the glomerulus in order to halt disease development. This study examined whether inhibition of the receptor for macrophage colony-stimulating factor (known as c-fms), which is selectively expressed by monocyte/macrophages, can eliminate the macrophage infiltrate in a rat model of crescentic anti-GBM glomerulonephritis. Wistar-Kyoto rats were treated with 10 or 30 mg/kg bid of fms-I (a selective c-fms kinase inhibitor) from the time of anti-GBM serum injection until being killed 1, 5 or 14 days later. fms-I treatment had only a minor effect upon the glomerular macrophage infiltrate on day 1 and did not prevent the subsequent induction of proteinuria. However, fms-I treatment reduced the glomerular macrophage infiltrate by 60% at day 5 and completely reversed the macrophage infiltrate by day 14. In addition, fms-I treatment downregulated the glomerular expression of pro-inflammatory molecules (TNF-α, NOS2, MMP-12, CCL2 and IL-12) on days 1 and 5, suggesting a suppression of the macrophage M1-type response. Despite a significant early loss of glomerular podocytes, ongoing proteinuria and glomerular tuft adhesions to Bowman's capsule, the reversal of the macrophage infiltrate prevented the development of glomerulosclerosis, crescent formation, tubulointerstitial damage and renal dysfunction. In conclusion, this study has identified c-fms kinase inhibition as a selective approach to target infiltrating macrophages in acute glomerular injury, which may have therapeutic potential in rapidly progressive crescentic glomerulonephritis.


Assuntos
Glomerulonefrite/patologia , Glomérulos Renais/patologia , Macrófagos/patologia , Receptor de Fator Estimulador de Colônias de Macrófagos/antagonistas & inibidores , Animais , Sequência de Bases , Primers do DNA , Glomerulonefrite/fisiopatologia , Imuno-Histoquímica , Masculino , Proteinúria/fisiopatologia , Ratos , Ratos Endogâmicos WKY , Ratos Wistar , Reação em Cadeia da Polimerase Via Transcriptase Reversa
14.
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
15.
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.

16.
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
17.
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
18.
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.

19.
Nephrology (Carlton) ; 13(5): 411-8, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18331439

RESUMO

AIM: A number of growth factors have been shown to induce proliferation of renal cell types in animal models of kidney disease. In vitro studies suggest that many such growth factors induce renal cell proliferation through the extracellular signal-regulated kinase (ERK) pathway. The aim of this study was to determine the functional role of ERK signalling in cell proliferation in the obstructed kidney. METHODS: Unilateral ureteric obstruction was induced in C57BL/6J mice which then received an ERK inhibitor drug (U0126 100 mg/kg t.i.d.), vehicle (DMSO) or no treatment, starting at day 2 after unilateral ureteric obstruction surgery and continuing until animals were killed on day 5. Cell proliferation was assessed by uptake of bromodeoxyuridine (BrdU). RESULTS: In normal mice, phosphorylation (activation) of ERK (p-ERK) was restricted to collecting ducts. Western blotting identified a marked increase in p-ERK in the obstructed kidney in the no-treatment and vehicle-treated groups. Immunostaining showed strong p-ERK staining in many tubules and in interstitial cells. U0126 treatment inhibited ERK phosphorylation as assessed by western blot and immunostaining. The number of BrdU+ cortical tubular cells was reduced by vehicle treatment but was not further changed by U0126 treatment. In contrast, interstitial cell proliferation in the obstructed kidney was unaltered by vehicle treatment, but this was significantly inhibited by U0126. This was associated with a reduction in interstitial macrophage accumulation, but no effect was seen upon interstitial accumulation of alpha-SMA+ myofibroblasts. Renal fibrosis, as assessed by collagen deposition, was unaffected by U0126 or vehicle treatment. CONCLUSION: These studies show that accumulation of interstitial macrophages in the obstructed kidney is, in part, dependent upon the ERK signalling pathway.


Assuntos
Nefropatias/enzimologia , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Transdução de Sinais , Animais , Butadienos/administração & dosagem , Butadienos/farmacologia , Proliferação de Células/efeitos dos fármacos , Inibidores Enzimáticos/administração & dosagem , Inibidores Enzimáticos/farmacologia , Macrófagos/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Nitrilas/administração & dosagem , Nitrilas/farmacologia , Obstrução Ureteral/cirurgia
20.
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
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