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1.
Microbiol Spectr ; 10(5): e0149422, 2022 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-36129300

RESUMO

Antibiotic-resistant bacteria have become a public health problem. Thus, antimicrobial peptides (AMPs) have been evaluated as substitutes for antibiotics. Herein, we investigated PN5 derived from Pinus densiflora (pine needle). PN5 exhibited antimicrobial activity without causing cytotoxic effects. Based on these results, we examined the mode of action of PN5 against Gram-negative and -positive bacteria. PN5 exhibited membrane permeabilization ability, had antimicrobial stability in the presence of elastase, a proteolytic enzyme, and did not induce resistance in bacteria. Bacterial lipopolysaccharide (LPS) induces an inflammatory response in RAW 264.7 macrophages. PN5 suppressed proinflammatory cytokines mediated by NF-κB and mitogen-activated protein kinase signaling. In C57BL/6J mice treated with LPS and d-galactosamine, PN5 exhibited anti-inflammatory activity in inflamed mouse livers. Our results indicate that PN5 has antimicrobial and anti-inflammatory activities and thus may be useful as an antimicrobial agent to treat septic shock caused by multidrug-resistant (MDR) Escherichia coli without causing further resistance. IMPORTANCE Antibiotic-resistant bacteria are a global health concern. There is no effective treatment for antibiotic-resistant bacteria, and new alternatives are being suggested. The present study found antibacterial and anti-inflammatory activities of PN5 derived from Pinus densiflora (pine needle), and further investigated the therapeutic effect in a mouse septic model. As a mechanism of antibacterial activity, PN5 exhibited the membrane permeabilization ability of the toroidal model, and treated strains did not develop drug resistance during serial passages. PN5 showed immunomodulatory properties of neutralizing LPS in a mouse septic model. These results indicate that PN5 could be a new and promising therapeutic agent for bacterial infectious disease caused by antibiotic-resistant strains.


Assuntos
Anti-Infecciosos , Choque Séptico , Camundongos , Animais , Escherichia coli , Lipopolissacarídeos , Peptídeos Antimicrobianos , NF-kappa B/farmacologia , NF-kappa B/uso terapêutico , Camundongos Endogâmicos C57BL , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Choque Séptico/tratamento farmacológico , Anti-Infecciosos/uso terapêutico , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Modelos Animais de Doenças , Bactérias , Galactosamina/farmacologia , Galactosamina/uso terapêutico , Elastase Pancreática/farmacologia , Elastase Pancreática/uso terapêutico , Peptídeo Hidrolases/farmacologia , Peptídeo Hidrolases/uso terapêutico , Citocinas , Proteínas Quinases Ativadas por Mitógeno , Testes de Sensibilidade Microbiana
2.
Acta Biomater ; 151: 588-599, 2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-36002126

RESUMO

Hepatocellular carcinoma (HCC) is a common high-mortality malignancy which still needs efficient treatments. HCC patients undergoing extrahepatic metastases are mostly with unsatisfactory prognosis. Therefore, specific attention has been paid to extrahepatic HCC metastasis. We integrated Sorafenib (Sor) and glucose oxidase (GOx) into a N-acetyl-galactosamine (GalNAc) modified zeolitic imidazolate framework (ZIF-8), designated as SG@GR-ZIF-8, for targeted bimodal therapies of chemotherapy and starvation therapy against HCC. The hepatic delivery of SG@GR-ZIF was mediated by the specific recognition of GalNAc residues with asialoglycoprotein (ASGPR) on the liver cell surface. Sor is a clinically approved anti-proliferation and anti-angiogenesis drug for advanced HCC treatment. GOx can efficiently induce cell death and disturb malignant progression by suppressing glucose supply of cancer cells, which is highly associated with metabolic rewiring in metastasis. The nano-formulation exhibit significant anti-metastatic HCC activity against C5WN1 cells, a liver cancer stem cell-like cell line with tumorigenicity and pulmonary metastasis activity. In a subcutaneous C5WN1-tumor carrying mouse model, SG@GR-ZIF exhibits potent synergistic anti-tumor activity with a tumor inhibition rate of 89% and a prolonged survival status. The growth and pulmonary metastasis of HCC in an orthotopic mouse model of HCC was remarkably suppressed in SG@GR-ZIF treated group. The therapeutic strategy targeting energy supply combined with first-line treatment holds great promise for the future treatment of metastatic HCC. STATEMENT OF SIGNIFICANCE: SG@GR-ZIF, a N-acetyl-galactosamine modified metal-organic framework carrying Sorafenib and glucose oxidase, was fabricated for treating metastatic hepatocellular carcinoma (HCC). Sorafenib is an anti-proliferation and anti-angiogenesis drug for advanced HCC treatment. Glucose oxidase blocks energy demand in HCC metastasis by depleting glucose. C5WN1 was used for therapeutic evaluations as a liver cancer stem cell-like cell line with tumorigenicity and pulmonary metastasis activity. In subcutaneous C5WN1-tumor bearing mice, SG@GR-ZIF exhibited a tumor inhibition rate of 89% and prolonged survival period. In orthotopic C5WN1-tumor carrying mice, the growth and pulmonary metastasis of hepatocarcinoma was remarkably suppressed by SG@GR-ZIF. Together, this study suggests the great potential of synergistic chemo/starvation therapy mediated by SG@GR-ZIF for treating metastatic HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Neoplasias Pulmonares , Estruturas Metalorgânicas , Animais , Assialoglicoproteínas/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Galactosamina/uso terapêutico , Glucose , Glucose Oxidase/química , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Neoplasias Pulmonares/secundário , Estruturas Metalorgânicas/química , Estruturas Metalorgânicas/farmacologia , Camundongos , Células-Tronco Neoplásicas/patologia , Sorafenibe
3.
J Hepatol ; 77(4): 967-977, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35714812

RESUMO

BACKGROUND & AIMS: Bepirovirsen, an antisense oligonucleotide targeting pregenomic and mRNA transcripts of HBV, has been conjugated to N-acetyl galactosamine (GSK3389404) to enhance hepatocyte delivery. This dose-finding study was the first to assess GSK3389404 for chronic HBV infection. METHODS: This phase IIa, randomised, double-blind, placebo-controlled, 2-part study was conducted in 22 centres in Asia (NCT03020745). Pharmacokinetic findings from Part 1 informed Part 2 dosing. In Part 2, patients with chronic hepatitis B on nucleos(t)ide analogue therapy were randomised 11:2 to GSK3389404 (30, 60, 120 mg weekly or 120 mg bi-weekly) or placebo until Day 85. Coprimary endpoints included HBsAg response (≥1.5 log10 IU/ml reduction from baseline) rate, safety and pharmacokinetics. RESULTS: Parts 1 and 2 included 12 (9 GSK3389404, 3 placebo) and 66 patients (56 GSK3389404, 10 placebo), respectively. In Part 2, one patient each in the 60 mg weekly, 120 mg weekly and 120 mg bi-weekly arms achieved a HBsAg response. HBsAg reductions were dose-dependent (Day 85: mean 0.34 [60 mg weekly] to 0.75 log10 IU/ml [120 mg weekly]) and occurred in hepatitis B e antigen-positive and -negative patients. No patient achieved HBsAg seroclearance. 43/56 (77%) GSK3389404- and 9/10 (90%) placebo-treated patients reported adverse events. No deaths were reported. Alanine aminotransferase flares (>2x upper limit of normal) occurred in 2 GSK3389404-treated patients (120 mg weekly, 120 mg bi-weekly); both were associated with decreased HBsAg, but neither was considered a responder. GSK3389404 plasma concentrations peaked 2-4 hours post dose; mean plasma half-life was 3-5 hours. CONCLUSIONS: GSK3389404 showed an acceptable safety profile and target engagement, with dose-dependent reductions in HBsAg. However, no efficacious dosing regimen was identified. CLINICAL TRIAL NUMBER: NCT03020745. LAY SUMMARY: Hepatitis B virus (HBV) can result in chronic HBV infection, which may ultimately lead to chronic liver disease, primary liver cancer and death; HBV proteins may prevent the immune system from successfully controlling the virus. GSK3389404 is an investigational agent that targets HBV RNA, resulting in reduced viral protein production. This study assessed the safety of GSK3389404 and its ability to reduce the viral proteins in patients with chronic HBV infection. GSK3389404 showed dose-dependent reduction in hepatitis B surface antigen, with an acceptable safety profile. While no clear optimal dose was identified, the findings from this study may help in the development of improved treatment options for patients with chronic HBV infections.


Assuntos
Hepatite B Crônica , Alanina Transaminase , Antivirais/efeitos adversos , DNA Viral , Método Duplo-Cego , Galactosamina/uso terapêutico , Antígenos de Superfície da Hepatite B , Antígenos E da Hepatite B , Vírus da Hepatite B/genética , Humanos , Oligonucleotídeos Antissenso/uso terapêutico , RNA , RNA Mensageiro , Proteínas Virais
4.
Shock ; 57(3): 444-456, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-34923545

RESUMO

BACKGROUND: Omeprazole (OMZ) is a proton pump inhibitor that is used to reduce gastric acid secretion, but little is known about its possible liver protective effects. This study investigated whether OMZ has beneficial effects in rat septic models of LPS-induced liver injury after D-galactosamine (GalN) treatment and 70% hepatectomy (PH), and to determine the mechanisms of OMZ in an in vitro model of liver injury. METHODS: In the in vivo models, the effects of OMZ were examined 1 h before treatments in both models on survival, nuclear factor (NF)-κB activation, histopathological analysis, and proinflammatory mediator expression in the liver and serum. In the in vitro model, primary cultured rat hepatocytes were treated with IL-1ß in the presence or absence of OMZ. The influence of OMZ on nitric oxide (NO) product and inducible NO synthase (iNOS) induction and on the associated signaling pathway was analyzed. RESULTS: OMZ increased survival and decreased tumor necrosis factor-alpha, iNOS, cytokine-induced neutrophil chemoattractant 1, IL-6, and IL-1ß mRNA expression, and increased IL-10 mRNA expression in the livers of both GaIN/LPS- and PH/LPS-treated rats. Necrosis and apoptosis were inhibited by OMZ in GaIN/LPS rats, but OMZ had no effects on necrosis in PH/LPS rats. OMZ inhibited iNOS induction partially through suppression of NF-κB signaling in hepatocytes. CONCLUSIONS: OMZ inhibited the induction of several inflammatory mediators, resulting in the prevention of LPS-induced liver injury after GalN liver failure and PH, although OMZ showed different doses and mechanisms in the two models.


Assuntos
Mediadores da Inflamação/metabolismo , Falência Hepática Aguda/terapia , Omeprazol/farmacologia , Inibidores da Bomba de Prótons/farmacologia , Sepse/complicações , Animais , Técnicas de Cultura de Células , Modelos Animais de Doenças , Galactosamina/uso terapêutico , Hepatectomia , Hepatócitos/efeitos dos fármacos , Falência Hepática Aguda/etiologia , Falência Hepática Aguda/metabolismo , Masculino , Óxido Nítrico Sintase Tipo II/metabolismo , Ratos , Ratos Sprague-Dawley , Sepse/metabolismo , Sepse/patologia
5.
Iran J Med Sci ; 46(5): 373-382, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34539012

RESUMO

Background: Acute liver failure (ALF) is a fatal clinical situation that rapidly leads to the loss of normal liver function. Esculetin is a natural herbal compound used for the management of various diseases such as cardiovascular and renal disorders. In this study, we evaluated the protective effects of esculetin in a mouse model of ALF. Methods: This article is a report on an experimental study that was conducted at Iran University of Medical Sciences in 2019. Forty-eight male C57BL/6 mice were randomly divided into control, LPS/D-Gal, and LPS/D-Gal+Esculetin (40 mg/kg) groups (n=16 per group). ALF was induced with an intraperitoneal injection of lipopolysaccharide (LPS)/D-galactosamine (D-Gal).The LPS/D-Gal group received a mixture of LPS (50 µg/kg) and D-Gal (400 mg/kg). The LPS/D-Gal+Esculetin group received esculetin by gavage 24 hours and one hour before receiving LPS/D-Gal. Six hours after LPS/D-Gal injection, the mice were sacrificed. Liver injury markers, including alanine aminotransferase (ALT), aspartate transaminase (AST), and alkaline phosphatase (ALP), were measured in the serum. Oxidative stress indices and inflammatory markers such as interleukin-1 beta (IL-1ß), IL-6, and tumor necrosis factor-alpha (TNF-α) were measured in hepatic tissue. The histopathology of liver tissue was also assessed. The data were analyzed using one-way ANOVA, followed by the post hoc Tukey test. Results: Esculetin lowered oxidative stress and myeloperoxidase activity (P<0.001); reduced the serum levels of ALT (P=0.037), AST (P=0.032), and ALP (P=0.004); and decreased the hepatic levels of IL-1ß (P=0.002), IL-6 (P=0.004), toll-like receptor 4 (P<0.001), TNF-α (P=0.003), and nuclear factor-kappa B (P<0.001) as compared with LPS/D-Gal. Additionally, esculetin ameliorated hepatic tissue injury following LPS/D-Gal challenge. Conclusion: Esculetin can reduce liver injury through the mitigation of oxidative burden, inflammation, and neutrophil infiltration and also exerts hepatoprotective effects against ALF.


Assuntos
Galactosamina/farmacologia , Lipopolissacarídeos/farmacologia , Falência Hepática Aguda/tratamento farmacológico , Umbeliferonas/farmacologia , Animais , Modelos Animais de Doenças , Galactosamina/uso terapêutico , Interleucina-1beta/análise , Interleucina-1beta/sangue , Interleucina-6/análise , Interleucina-6/sangue , Irã (Geográfico) , Lipopolissacarídeos/uso terapêutico , Falência Hepática Aguda/patologia , Falência Hepática Aguda/fisiopatologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fragmentos de Peptídeos/análise , Fragmentos de Peptídeos/sangue , Fatores de Proteção , Receptor 4 Toll-Like/análise , Receptor 4 Toll-Like/sangue , Umbeliferonas/uso terapêutico
6.
J Med Chem ; 62(2): 467-479, 2019 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-30540910

RESUMO

The F9/Yde/Fml pilus, tipped with the FmlH adhesin, has been shown to provide uropathogenic Escherichia coli (UPEC) a fitness advantage in urinary tract infections (UTIs). Here, we used X-ray structure guided design to optimize our previously described ortho-biphenyl Gal and GalNAc FmlH antagonists such as compound 1 by replacing the carboxylate with a sulfonamide as in 50. Other groups which can accept H-bonds were also tolerated. We pursued further modifications to the biphenyl aglycone resulting in significantly improved activity. Two of the most potent compounds, 86 (IC50 = 0.051 µM) and 90 (IC50 = 0.034 µM), exhibited excellent metabolic stability in mouse plasma and liver microsomes but showed only limited oral bioavailability (<1%) in rats. Compound 84 also showed a good pharmacokinetic (PK) profile in mice after IP dosing with compound exposure above the IC50 for 6 h. These new FmlH antagonists represent new antivirulence drugs for UTIs.


Assuntos
Adesinas de Escherichia coli/química , Compostos de Bifenilo/química , Desenho de Fármacos , Galactosamina/química , Galactose/química , Adesinas de Escherichia coli/metabolismo , Administração Oral , Animais , Galactosamina/farmacocinética , Galactosamina/uso terapêutico , Galactose/farmacocinética , Meia-Vida , Humanos , Camundongos , Microssomos Hepáticos/metabolismo , Ratos , Relação Estrutura-Atividade , Infecções Urinárias/tratamento farmacológico , Escherichia coli Uropatogênica
7.
Dis Markers ; 2018: 6484610, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30018675

RESUMO

OBJECTIVE: To investigate the ratios of creatine kinase (CK) to aminotransferases as biomarkers of acute liver injury in dystrophinopathy. METHODS: C57 and mdx (dystrophic) mice were treated with a hepatotoxic reagent D-galactosamine (D-GalN). The degrees of liver and muscle injury were assessed using histological examinations. To examine whether serum CK-adjusted aminotransferase levels could indicate liver status in dystrophic mice, the CK/alanine aminotransferase (ALT) and CK/aspartate aminotransferase (AST) ratios were analyzed. Furthermore, we enrolled 658 male patients with dystrophinopathy and 378 male patients without muscle and liver injury as control, whose serum ALT, AST, and CK levels were examined. RESULTS: Animal experiments indicated that D-GalN treatment could induce acute liver injury but not muscle injury. Additionally, D-GalN decreased the CK/ALT and CK/AST ratios in both C57 mice and mdx mice (P < 0.001). However, there was an overlap of the CK/AST ratio between dystrophic mice with and without acute liver injury. In patients with dystrophinopathy, CK-adjusted ALT diminished the variability associated with age, genotype, clinical phenotype, and motor function (P > 0.05). CONCLUSIONS: CK/ALT is a potential biomarker for the differential evaluation of acute liver injury in dystrophic mice, which highlights the value to further evaluate the practice of CK/ALT in dystrophinopathy patients.


Assuntos
Alanina Transaminase/sangue , Doença Hepática Induzida por Substâncias e Drogas/sangue , Creatina Quinase/sangue , Distrofias Musculares/complicações , Adolescente , Animais , Biomarcadores/sangue , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Criança , Galactosamina/efeitos adversos , Galactosamina/uso terapêutico , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos mdx , Distrofias Musculares/tratamento farmacológico
8.
World J Gastroenterol ; 24(10): 1093-1106, 2018 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-29563754

RESUMO

AIM: To design colon-targeted codrugs of mycophenolic acid (MPA) and aminosugars as a safer option to mycophenolate mofetil (MMF) in the management of inflammatory bowel disease. METHODS: Codrugs were synthesized by coupling MPA with aminosugars (D-glucosamine and D-galactosamine) using EDCI coupling. The structures were confirmed by infrared radiation, nuclear magnetic resonance, mass spectroscopy and elemental analysis. The release profile of codrugs was extensively studied in aqueous buffers, upper gastrointestinal homogenates, faecal matter and caecal homogenates (in vitro) and rat blood (in vitro). Anti-colitic activity was assessed in 2,4,6-trinitrobezenesulfonic acid-induced colitis in Wistar rats by the estimation of various demarcating parameters. Statistical evaluation was performed by applying one-way and two-way ANOVA when compared with the disease control. RESULTS: The prodrugs resisted activation in HCl buffer (pH 1.2) and stomach homogenates of rats with negligible hydrolysis in phosphate buffer (pH 7.4) and intestinal homogenates. Incubation with colon homogenates (in vitro) produced 76% to 89% release of MPA emphasizing colon-specific activation of codrugs and the release of MPA and aminosugars at the site of action. In the in vitro studies, the prodrug of MPA with D-glucosamine (MGLS) was selected which resulted in 68% release of MPA in blood. in vitro studies on MGLS revealed its colon-specific activation after a lag time of 8 h which could be ascribed to the hydrolytic action of N-acyl amidases found in the colon. The synthesized codrugs markedly diminished disease activity score and revived the disrupted architecture of the colon that was comparable to MMF but superior to MPA. CONCLUSION: The significant attenuating effect of prodrugs and individual aminosugars on colonic inflammation proved that the rationale of the codrug approach is valid.


Assuntos
Colite Ulcerativa/tratamento farmacológico , Imunossupressores/uso terapêutico , Pró-Fármacos/uso terapêutico , Animais , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/patologia , Colo/efeitos dos fármacos , Colo/metabolismo , Colo/patologia , Modelos Animais de Doenças , Liberação Controlada de Fármacos , Sinergismo Farmacológico , Galactosamina/síntese química , Galactosamina/farmacologia , Galactosamina/uso terapêutico , Mucosa Gástrica/metabolismo , Glucosamina/síntese química , Glucosamina/farmacologia , Glucosamina/uso terapêutico , Humanos , Imunossupressores/síntese química , Imunossupressores/farmacologia , Masculino , Ácido Micofenólico/síntese química , Ácido Micofenólico/farmacologia , Ácido Micofenólico/uso terapêutico , Pró-Fármacos/síntese química , Pró-Fármacos/farmacologia , Ratos , Ratos Wistar , Índice de Gravidade de Doença , Resultado do Tratamento , Ácido Trinitrobenzenossulfônico/toxicidade
9.
Biomaterials ; 83: 93-101, 2016 03.
Artigo em Inglês | MEDLINE | ID: mdl-26773662

RESUMO

Osteoarthritis (OA) is a degenerative joint disease characterized by articular cartilage degradation. Because OA has a multifactorial nature and complex interrelationship of the individual elements of a whole joint, there is a need for comprehensive therapeutic approaches for cartilage tissue engineering, which simultaneously address multiple aspects of disease etiology. In this work, we investigated a multifunctional carbohydrate-based drug candidate, tri-butanoylated N-acetyl-D-galactosamine analog (3,4,6-O-Bu3GalNAc) that induced cartilage tissue production by human mesenchymal stem cells (hMSCs) and human OA chondrocytes by modulating Wnt/ß-catenin signaling activity. The dual effects promoted chondrogenesis of human MSC and reduced inflammation of human OA chondrocytes in in vitro cultures. Translating these findings in vivo, we evaluated therapeutic effect of 3,4,6-O-Bu3GalNAc on the rat model of posttraumatic OA when delivered via local intra-articular sustained-release delivery using microparticles and found this method to be efficacious in preventing OA progression. These results show that 3,4,6-O-Bu3GalNAc, a disease modifying OA drug candidate, has promising therapeutic potential for articular cartilage repair.


Assuntos
Cartilagem Articular/patologia , Sistemas de Liberação de Medicamentos , Galactosamina/uso terapêutico , Inflamação/tratamento farmacológico , Osteoartrite/tratamento farmacológico , Regeneração , Animais , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Biomarcadores/metabolismo , Cartilagem Articular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Condrócitos/efeitos dos fármacos , Condrócitos/metabolismo , Condrócitos/patologia , Condrogênese/efeitos dos fármacos , Modelos Animais de Doenças , Matriz Extracelular/efeitos dos fármacos , Matriz Extracelular/metabolismo , Galactosamina/química , Galactosamina/farmacologia , Humanos , Inflamação/complicações , Inflamação/patologia , Masculino , Osteoartrite/complicações , Osteoartrite/patologia , Ratos Sprague-Dawley , Regeneração/efeitos dos fármacos
10.
Hepatobiliary Pancreat Dis Int ; 10(6): 611-9, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22146625

RESUMO

BACKGROUND: A reliable model of fulminant liver failure (FLF) is urgently required in this research field. This study aimed to develop a murine FLF model. METHODS: We used three groups of male C57BL/6 mice: control, with azoxymethane treatment (AOM group), and with galactosamine and tumor necrosis factor-alpha treatment (Gal+TNF-alpha group). The effects of body temperature (BT) control on survival in all three groups were investigated. Using BT control, we compared the survival, histopathological findings and biochemical/coagulation profiles between the two experimental groups. The effects of hydration on international normalized ratios of prothrombin time (PT-INRs) were also checked. Dose-dependent survival curves were constructed for both experimental groups. Neurological behavior was assessed using a coma scale. RESULTS: No unexpected BT effects were seen in the control group. The AOM group, but not the Gal+TNF-alpha group, showed a significant difference in survival curves between those with and without BT care. Histopathological assessment showed consistent FLF findings in both experimental groups with BT care. There were significant differences between the experimental groups in aspartate aminotransferase levels and PT-INRs, and significant differences in PT-INRs between the sufficiently and insufficiently hydrated groups. There were significant differences between FLF models in the duration of each coma stage, with significant differences in stages 1 and 3 as percentages of the disease state (stages 1-4). The two FLF models with BT care showed different survival curves in the dose-dependent survival study. CONCLUSIONS: AOM provides a good FLF model, but requires a specialized environment and careful BT control. Other FLF models may also be useful, depending on the research purpose. Thoughtful attention to caregiving and close observation are indispensable for successful FLF models.


Assuntos
Compostos Azo/uso terapêutico , Galactosamina/uso terapêutico , Encefalopatia Hepática/tratamento farmacológico , Falência Hepática Aguda/tratamento farmacológico , Fator de Necrose Tumoral alfa/uso terapêutico , Animais , Modelos Animais de Doenças , Encefalopatia Hepática/etiologia , Encefalopatia Hepática/mortalidade , Falência Hepática Aguda/complicações , Falência Hepática Aguda/mortalidade , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Prognóstico , Taxa de Sobrevida , Resultado do Tratamento
11.
Neurología (Barc., Ed. impr.) ; 25(4): 239-247, jun. 2010. ilus, tab
Artigo em Espanhol | IBECS | ID: ibc-94718

RESUMO

Introducción: La fibrosis hepática y su etapa final, la cirrosis, representan un enorme problema de salud mundial. La encefalopatía hepática (EH) o encefalopatía portosistémica es una afección clínica de la cirrosis a largo plazo. En esta revisión se destacan las bases moleculares de la EH, así como el papel del estrés oxidativo en el desarrollo de esta enfermedad.Fuentes: Diversos estudios señalan que la EH es de origen multifactorial, las alteraciones en la barrera hematoencefálica, sustancias como el amonio y el manganeso, así como alteraciones en la neurotransmisión de dopamina, glutamato y GABA, se han implicado en la patogenia de esta enfermedad. Desarrollo: La EH es una complicación severa de la insuficiencia hepática tanto aguda como crónica. Neuropatológicamente, se caracteriza por cambios astrocitarios conocidos como astrocitosis Alzheimer tipo II y por la expresión alterada de proteínas específicas de astrocito, como la proteína acídica fibrilar glial, la glutamina sintetasa, los inhibidores de la monoaminooxidasa y los receptores periféricos tipo benzodiacepina.Conclusiones: La EH es un síndrome neuropsiquiátrico complejo asociado a una falla hepática. Estas alteraciones son producto de un incremento de estrés oxidativo en el cerebro como consecuencia de la acción de neurotoxinas. La principal estrategia para el tratamiento de la EH se dirige a la reducción del amonio, ya sea por la disminución de su absorción/producción o promoviendo su eliminación (AU)


Introduction: Liver fibrosis and its end stage, cirrhosis, is an enormous worldwide health problem. Hepatic encephalopathy (HE) or portal-systemic encephalopathy continues to be a major clinical problem of long-term cirrhosis. In this review we emphasise the molecular basis of HE and the involvement of oxidative stress in the development of this disease.Background: Several studies suggest that the pathogenesis of HE could be multifactorial and have implicated different factors, such as alterations in blood brain barrier, substances; such as ammonia and manganese, neurotransmission disorders such as dopamine, glutamate and GABA.Development: HE is a severe complication of both acute and chronic liver failure. Neuropathologically, it is characterized by astrocyte changes known as Alzheimer type II astrocytosis. In addition, astrocytes manifest altered expression of astrocyte-specific proteins, such as, glial fibrillary acidic protein, glutamine synthetase, monoamine oxidase and peripheral type benzodiazepine receptors. Conclusions:HE is a complex neuropsychiatric syndrome associated with liver failure. These alterations are products of increases in oxidative stress in brain due to neurotoxin activity. The main strategy for HE treatment is directed at ammonia reduction, which can be achieved either by decreasing its absorption/production or increasing its removal (AU)


Assuntos
Humanos , Encefalopatia Hepática/fisiopatologia , Endotoxinas/efeitos adversos , Gliose/fisiopatologia , Neurotoxinas/efeitos adversos , Estresse Oxidativo , Modelos Animais de Doenças , Proteínas da Membrana Plasmática de Transporte de Dopamina/fisiologia , Proteínas de Transporte de Glutamato da Membrana Plasmática/fisiologia , Galactosamina/uso terapêutico , Compostos de Amônio Quaternário/toxicidade , Manganês/toxicidade
12.
Infect Immun ; 59(6): 2110-5, 1991 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2037372

RESUMO

Treatment with D-galactosamine increases sensitivity of lipopolysaccharide (LPS)-responder mice to the lethal effects of LPS, while nonresponder mice remain resistant (M.A. Freudenberg, D. Keppler, and C. Galanos, Infect. Immun. 51:891-895, 1986). In the present study it is shown that, in contrast to LPS, killed gram-negative bacteria (Salmonella abortus equi and S. typhimurium) were highly toxic for D-galactosamine-treated LPS-responder (C57BL/10 ScSN and C3H/HeN) and -nonresponder (C57BL/10 ScCR and C3H/HeJ) mice, although to a higher extent in the former strains. Also, killed gram-positive bacteria (Staphylococcus aureus, Propionibacterium acnes, and Mycobacterium phlei) exhibited toxicity for D-galactosamine-treated mice, LPS-responder and -nonresponder mice being equally susceptible. Evidently, bacterial components other than LPS may exhibit lethal effects in sensitized animals. In all cases, the lethality of LPS and of bacteria was inhibited by anti-tumor necrosis factor alpha (TNF-alpha) serum. While LPS induced TNF-alpha in vitro only in macrophages from LPS-responder mice, gram-negative and gram-positive bacteria induced TNF-alpha also in macrophages from LPS-nonresponder mice. The data show that TNF-alpha is a common endogenous mediator of the lethal activity of gram-negative and gram-positive bacteria.


Assuntos
Infecções Bacterianas/imunologia , Galactosamina/uso terapêutico , Bactérias Gram-Negativas , Bactérias Gram-Positivas , Lipopolissacarídeos/toxicidade , Choque Séptico/imunologia , Fator de Necrose Tumoral alfa/imunologia , Animais , Infecções Bacterianas/tratamento farmacológico , Macrófagos , Camundongos , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Choque Séptico/tratamento farmacológico , Vacinas de Produtos Inativados
13.
Cancer Res ; 47(3): 696-9, 1987 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-3802075

RESUMO

We have previously reported that chloroethyl nitrosourea and nitrogen mustard bone marrow toxicity can be selectively reduced by placement of the cytotoxic group on specific positions of a glucose molecule. We have now synthesized and evaluated a new drug in which the mustard cytotoxic group is attached to the carbon-6 position of galactose (C6-GLM). C6-GLM, administered i.p. as a single 10% lethal dose of 15.5 mg/kg, produced a 121% increase in life span (ILS) in mice bearing the ascitic P388 leukemia, compared to a 60% ILS with a 10% lethal dose of nitrogen mustard (P less than 0.01). A single p.o. dose of C6-GLM, 16 mg/kg, produced an ILS of 58%. Against i.p.-implanted B-16 melanoma, i.p. C6-GLM produced a 56% ILS compared to 30% with an equitoxic dose of nitrogen mustard (P less than 0.01). The activity of the two drugs for Ehrlich ascites was comparable, with 60% survivors with the galactose mustard. A single 10% lethal dose of C6-GLM reduced the white blood cells to 74% of control; circulating granulocytes remained at 91% of initial values. With nitrogen mustard, the nadir white blood cell count was 57% of control with an absolute granulocyte count of 70% of initial values (P less than 0.01). The toxicity of melphalan was considerably greater, with a lower and more protracted while blood cell nadir and an absolute neutrophil count nadir of 49% of control. These findings paralleled the relative decrements in bone marrow DNA synthesis produced by the three drugs. Measurement of human bone marrow granulocyte-macrophage colony-forming units, following in vitro exposure to graded concentrations of the three mustards, confirmed the bone marrow sparing properties of C6-GLM. At the highest concentration, 1 X 10(-2) mM, the latter drug produced only a 33% reduction in colonies compared to a 75% reduction with nitrogen mustard and a virtual elimination of activity of colony-forming units with melphalan. The demonstration of antitumor activity, at least equivalent to nitrogen mustard, without the necessity of significant bone marrow toxicity supports the development of C6-GLM for clinical trials in humans.


Assuntos
Medula Óssea/patologia , Galactosamina/análogos & derivados , Células-Tronco Hematopoéticas/citologia , Leucemia P388/tratamento farmacológico , Leucemia Experimental/tratamento farmacológico , Animais , Medula Óssea/efeitos dos fármacos , Replicação do DNA/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos , Feminino , Galactosamina/uso terapêutico , Galactosamina/toxicidade , Células-Tronco Hematopoéticas/efeitos dos fármacos , Leucopenia/induzido quimicamente , Masculino , Mecloretamina/toxicidade , Melfalan/toxicidade , Camundongos , Camundongos Endogâmicos DBA , Neutrófilos/citologia , Relação Estrutura-Atividade
15.
Adv Enzyme Regul ; 24: 429-34, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-2424285

RESUMO

Sixteen unselected patients with non-resectable hepatocellular carcinoma were treated in a phase I study with 261 cycles of D-galactosamine and 6-azauridine prior to 5-fluorouridine. Thirty % of the patients survived for more than one year without signs of tumor progression and with an unchanged performance status. The compatibility of this chemotherapeutical method was quite satisfactory. The only extrahepatic side effect was a leucopenia and/or thrombocytopenia which was reversible upon reduction of the 5-fluorouridine dose. The heterogeneity of the 16 patients treated to date does not allow a definite statistical evaluation of the reported clinical observations and results. A final decision about the clinical applicability of this concept of a selective chemotherapy of hepatocellular carcinoma requires further experience.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Uridina/análogos & derivados , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Azauridina/uso terapêutico , Carcinoma Hepatocelular/mortalidade , Feminino , Galactosamina/uso terapêutico , Humanos , Neoplasias Hepáticas/mortalidade , Masculino , Pessoa de Meia-Idade , Uridina/efeitos adversos , Uridina/uso terapêutico
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