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1.
Liver Int ; 43(12): 2701-2712, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37752797

RESUMO

BACKGROUND & AIMS: Direct-acting antiviral (DAA) therapy has revolutionized treatment for the hepatitis C virus (HCV). While DAA therapy is common, little is known about the intrahepatic immunological changes after sustained virologic response (SVR). We aim to describe transcriptional alterations of the gut microbiome and the liver after SVR. METHODS: Twenty-two HCV patients were evaluated before and 9 months after 12 weeks of sofosbuvir/velpatasvir treatment. All achieved SVR. A liver biopsy, portal blood (direct portal vein cannulation), peripheral blood and stool samples were obtained. RNA-seq and immunofluorescent staining were performed on liver biopsies. RNA-seq and 16S rRNA metagenomics were performed on stool. RESULTS: Differential expression within liver transcription showed 514 downregulated genes (FDR q < .05; foldchange > 2) enriched in inflammatory pathways; of note, GO:0060337, type 1 IFN signalling (p = 8e-23) and GO:0042742, defence response to bacterium (p = 8e-3). Interestingly, microbial products increased in the portal blood and liver after SVR. Due to the increase in microbial products, the gut microbiome was investigated. There was no dysbiosis by Shannon diversity index or Bacteroides/Firmicutes ratio. There was a differential increase in genes responsible for bacterial lipopolysaccharide production after SVR. CONCLUSIONS: The decrease in the antiviral interferon pathway expression was expected after SVR; however, there was an unanticipated decrease in the transcription of genes involved in recognition and response to bacteria, which was associated with increased levels of microbial products. Finally, the alterations in the function of the gut microbiome are a promising avenue for further investigation of the gut-liver axis, especially in the context of the significant immunological changes noted after SVR.


Assuntos
Hepatite C Crônica , Hepatite C , Humanos , Antivirais/uso terapêutico , Hepacivirus , Hepatite C Crônica/complicações , Endotoxinas/uso terapêutico , RNA Ribossômico 16S/genética , Hepatite C/complicações , Resposta Viral Sustentada , Quimiocinas/uso terapêutico , Imunidade
2.
Contrib Nephrol ; 200: 133-141, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37263237

RESUMO

In the fields of sepsis and systemic inflammation, endotoxin might be the most studied molecule since the term was coined by Richard Pfeiffer in 1892. Paradoxically measuring endotoxin in humans and finding an effective treatment for endotoxemia have remained challenging. While advances have been made in understanding the mechanisms of how this simple molecule can trigger an intense immune cascade, there is an ever growing need to develop better treatments. Studies measuring endotoxin levels in patients with septic shock have consistently demonstrated that there is a dose-response relationship between endotoxin levels and adverse outcomes. A rapid assay to measure endotoxin activity has been available for more than a decade, but few studies have synergized the assay with a therapeutic. Polymyxin B hemoperfusion (PMX-HP) leverages a molecule with high affinity for endotoxin with a technique to eliminate exposure. Polymyxin is bound and immobilized to fibers within a cartridge and administered as an extracorporeal therapy via veno-venous hemoperfusion. Clinical evidence of its use is plentiful yet inconsistent in studies based on an outcome for mortality at 28 days. Herein, we describe targeted patient selection using the endotoxin activity assay and clinical phenotyping followed by adsorption of endotoxin using the PMX-HP for endotoxemic sepsis.


Assuntos
Sepse , Choque Séptico , Humanos , Endotoxinas/uso terapêutico , Adsorção , Sepse/terapia , Polimixina B/uso terapêutico , Choque Séptico/terapia , Antibacterianos/uso terapêutico
3.
Immunohorizons ; 6(7): 543-558, 2022 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-35882421

RESUMO

Warts, hypogammaglobulinemia, infections, and myelokathexis (WHIM) syndrome immunodeficiency is caused by autosomal dominant gain-of-function CXCR4 mutations that promote severe panleukopenia caused by bone marrow retention of mature leukocytes. Consequently, WHIM patients develop recurrent bacterial infections; however, sepsis is uncommon. To study this clinical dichotomy, we challenged WHIM model mice with LPS. The LD50 was similar in WHIM and wild-type (WT) mice, and LPS induced acute lymphopenia in WT mice that was Cxcr4 independent. In contrast, in WHIM mice, LPS did not affect circulating T cell levels, but the B cell levels anomalously increased because of selective, cell-intrinsic, and Cxcr4 WHIM allele-dependent emergence of Cxcr4high late pre-B cells, a pattern that was phenocopied by Escherichia coli infection. In both WT and WHIM mice, the CXCR4 antagonist AMD3100 rapidly increased circulating lymphocyte levels that then rapidly contracted after subsequent LPS treatment. Thus, LPS-induced lymphopenia is CXCR4 independent, and a WHIM mutation does not increase clinical LPS sensitivity. Anomalous WT Cxcr4-independent, but Cxcr4 WHIM-dependent, promobilizing effects of LPS on late pre-B cell mobilization reveal a distinct signaling pathway for the variant receptor.


Assuntos
Agamaglobulinemia , Linfopenia , Neutropenia , Verrugas , Agamaglobulinemia/genética , Animais , Endotoxinas/uso terapêutico , Lipopolissacarídeos , Camundongos , Neutropenia/genética , Doenças da Imunodeficiência Primária , Verrugas/tratamento farmacológico , Verrugas/genética
4.
Bioengineered ; 13(2): 2951-2970, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35148668

RESUMO

Sepsis is a type of systemic inflammation response syndrome that leads to organ function disorders. Currently, there is no specific medicine for sepsis in clinical practice. Lipopolysaccharide (LPS) is an important endotoxin that causes sepsis. Here, we report an effective two-drug combination therapy to treat LPS-induced liver and kidney injury in endotoxic rats. Ulinastatin (UTI) and Thrombomodulin (TM) are biological macromolecules extracted from urine. In our study, combination therapy significantly improved LPS-induced liver and kidney pathological structure and functional injury, and significantly improved the survival rate of endotoxic rats. Results of TUNEL staining and Western blot showed that UTI combined with TM inhibited the excessive apoptosis of liver and kidney cells caused by LPS. The drug combination also promoted the proliferation of liver and kidney cells, reduced the levels of pro-inflammatory factors interleukin (IL)-6, IL-1ß, tumor or necrosis factor (TNF)-α and nitric oxide, and down-regulated the expression of High Mobility Group Box 1 (HMGB1), Toll-like receptor (TLR) 4 and Nuclear Factor (NF)-κB phosphorylation to inhibit inflammation. In addition, the combination of UTI and TM also promoted the production of a variety of antioxidant enzymes in the tissues and inhibited the production of lipid peroxidation malondialdehyde (MDA) to enhance antioxidant defenses. Our experiments also proved that UTI combined with TM did not reduce the anticoagulant effect of TM. These results suggested that UTI combined with TM can improve endotoxin-induced liver and kidney damage and mortality by inhibiting liver and kidney cell apoptosis, promoting proliferation, and inhibiting inflammation and oxidative injury.


Assuntos
Proteína HMGB1 , Sepse , Animais , Antioxidantes , Apoptose , Endotoxinas/metabolismo , Endotoxinas/farmacologia , Endotoxinas/uso terapêutico , Glicoproteínas , Proteína HMGB1/metabolismo , Inflamação/metabolismo , Rim , Lipopolissacarídeos/toxicidade , Fígado/metabolismo , NF-kappa B/metabolismo , Estresse Oxidativo , Ratos , Sepse/tratamento farmacológico , Sepse/metabolismo , Transdução de Sinais , Trombomodulina/metabolismo , Trombomodulina/uso terapêutico , Receptor 4 Toll-Like/metabolismo
5.
Biochimie ; 192: 83-90, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34653542

RESUMO

Bacillus thuringiensis (Bt) is a ubiquitous bacterium that produces several proteins that are toxic to different invertebrates such as insects, nematodes, mites, and also some protozoans. Among these, Cry and Cyt proteins are most explored as biopesticides for their action against agricultural pests and vectors of human diseases. In 2000, a group of researchers from Japan isolated parasporal inclusion proteins from B. thuringiensis, and reported their cytotoxic action against human leukemia. Later, other proteins with similar antitumor properties were also isolated from this bacterium and these cytotoxic proteins with specific activity against human cancer cells were named parasporins. At present, nineteen different parasporins are registered and classified in six families. These parasporins have been described to have specific in vitro antitumor activity against several cancer cell lines. The antitumor activity makes parasporins possible candidates as anticancer agents. Various research groups around the world are involved in isolating and characterizing in vitro antitumor activity of these proteins and many articles reporting such activities in detail have been published. However, there are virtually no data regarding the antitumor activity of parasporins in vivo. This review summarizes the properties of these potentially useful antitumor agents of natural origin, focusing on their in vivo activity thus also highlighting the importance of testing these proteins in animal models for a possible application in clinical oncology.


Assuntos
Bacillus thuringiensis/química , Proteínas de Bactérias , Citotoxinas , Endotoxinas , Corpos de Inclusão Intranuclear/química , Leucemia/tratamento farmacológico , Animais , Proteínas de Bactérias/química , Proteínas de Bactérias/uso terapêutico , Linhagem Celular Tumoral , Citotoxinas/química , Citotoxinas/uso terapêutico , Endotoxinas/química , Endotoxinas/uso terapêutico , Humanos , Leucemia/metabolismo , Controle Biológico de Vetores
6.
J Am Vet Med Assoc ; 260(2): 194-211, 2022 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-34936576

RESUMO

OBJECTIVE: To characterize the frequency and type of bacterial infection by culture- and immunohistochemical (IHC)-based methods and determine the impact of infection on clinical features and survival time in cats with suppurative cholangitis-cholangiohepatitis syndrome (S-CCHS). ANIMALS: 168 client-owned cats with S-CCHS (cases). PROCEDURES: Clinical features, bacterial culture results, culture-inoculate sources, and survival details were recorded. Cases were subcategorized by comorbidity (extrahepatic bile duct obstruction, cholelithiasis, cholecystitis, ductal plate malformation, biopsy-confirmed inflammatory bowel disease, and biopsy-confirmed pancreatitis) or treatment by cholecystectomy or cholecystoenterostomy. Culture results, bacterial isolates, Gram-stain characteristics, and IHC staining were compared among comorbidities. Lipoteichoic acid IHC staining detected gram-positive bacterial cell wall components, and toll-like receptor expression IHC reflected pathologic endotoxin (gram-negative bacteria) exposure. RESULTS: Clinical features were similar among cases except for more frequent abdominal pain and lethargy in cats with positive culture results and pyrexia, abdominal pain, and hepatomegaly for cats with polymicrobial infections. Bacteria were cultured in 93 of 135 (69%) cats, with common isolates including Enterococcus spp and Escherichia coli. IHC staining was positive in 142 of 151 (94%) cats (lipoteichoic acid, 107/142 [75%]; toll-like receptor 4, 99/142 [70%]). With in-parallel interpretation of culture and IHC-based bacterial detection, 154 of 166 (93%) cats had bacterial infections (gram-positive, 118/154 [77%]; gram-negative, 111/154 [72%]; polymicrobial, 79/154 [51%]). Greater frequency of bacterial isolation occurred with combined tissue, bile, and crushed cholelith inoculates. Infection and gram-positive bacterial isolates were associated with significantly shorter long-term survival times. CLINICAL RELEVANCE: S-CCHS was associated with bacterial infection, pathologic endotoxin exposure, and frequent polymicrobial infection in cats. Combined tissue inoculates improved culture detection of associated bacteria.


Assuntos
Infecções Bacterianas , Doenças do Gato , Colangite , Animais , Antibacterianos/uso terapêutico , Infecções Bacterianas/veterinária , Bile/microbiologia , Doenças do Gato/tratamento farmacológico , Gatos , Colangite/tratamento farmacológico , Colangite/veterinária , Endotoxinas/uso terapêutico , Enterococcus
7.
Sci Adv ; 7(32)2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34362742

RESUMO

Systemic therapy of Gram-negative sepsis remains challenging. Polymyxin B (PMB) is well suited for sepsis therapy due to the endotoxin affinity and antibacterial activity. However, the dose-limiting toxicity has limited its systemic use in sepsis patients. For safe systemic use of PMB, we have developed a nanoparticulate system, called D-TZP, which selectively reduces the toxicity to mammalian cells but retains the therapeutic activities of PMB. D-TZP consists of an iron-complexed tannic acid nanocapsule containing a vitamin D core, coated with PMB and a chitosan derivative that controls the interaction of PMB with endotoxin, bacteria, and host cells. D-TZP attenuated the membrane toxicity associated with PMB but retained the ability of PMB to inactivate endotoxin and kill Gram-negative bacteria. Upon intravenous injection, D-TZP protected animals from pre-established endotoxemia and polymicrobial sepsis, showing no systemic toxicities inherent to PMB. These results support D-TZP as a safe and effective systemic intervention of sepsis.


Assuntos
Nanocápsulas , Sepse , Animais , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Endotoxinas/uso terapêutico , Humanos , Mamíferos , Nanocápsulas/uso terapêutico , Polimixina B/efeitos adversos , Sepse/tratamento farmacológico
8.
J Equine Vet Sci ; 77: 139-143, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31133308

RESUMO

Nonsteroidal anti-inflammatory drugs such as flunixin meglumine have been used to treat signs of systemic inflammatory conditions, but it is also known to have the side effect to small intestine mucosa. It may be considered to be due to inhibition of both cyclooxygenase (COX)-1 and COX-2. On the other hand, meloxicam is widely used in equine clinical practice and an effective nonsteroidal anti-inflammatory drug with the preferential inhibitory effect on COX-2. However, it has not yet been evaluated in equine systemic inflammation. The aim of this study was to evaluate the effect of meloxicam administered 60 minutes prior lipopolysaccharide (LPS)-induced inflammatory response in five Thoroughbred horses using a crossover test. Clinical parameters including body temperature, heart rate, respiratory rate, behavioral pain score, and hoof wall surface temperature were recorded, and plasma tumor necrosis factor-alpha, cortisol, and leukocyte counts were measured at various times before and after LPS infusion for 420 minutes. At time points 60, 90 (P < .01), 120, and 180 (P < .05) minutes, pain scores were significantly lower in meloxicam-treated horses. There was no significant difference in other parameters. In the present study, we revealed the analgesic effect of meloxicam using an equine low-dose endotoxin model.


Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Meloxicam , Administração Oral , Animais , Endotoxinas/uso terapêutico , Cavalos , Dor/tratamento farmacológico , Dor/veterinária
9.
Proc Natl Acad Sci U S A ; 115(39): 9690-9695, 2018 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-30194234

RESUMO

We report combined therapy using upconversion nanoparticles (UCNP) coupled to two therapeutic agents: beta-emitting radionuclide yttrium-90 (90Y) fractionally substituting yttrium in UCNP, and a fragment of the exotoxin A derived from Pseudomonas aeruginosa genetically fused with a targeting designed ankyrin repeat protein (DARPin) specific to HER2 receptors. The resultant hybrid complex UCNP-R-T was tested using human breast adenocarcinoma cells SK-BR-3 overexpressing HER2 receptors and immunodeficient mice, bearing HER2-positive xenograft tumors. The photophysical properties of UCNPs enabled background-free imaging of the UCNP-R-T distribution in cells and animals. Specific binding and uptake of UCNP complexes in SK-BR-3 cells was observed, with separate 90Y- and PE40-induced cytotoxic effects characterized by IC50 140 µg/mL (UCNP-R) and 5.2 µg/mL (UCNP-T), respectively. When both therapeutic agents were combined into UCNP-R-T, the synergetic effect increased markedly, ∼2200-fold, resulting in IC50 = 0.0024 µg/mL. The combined therapy with UCNP-R-T was demonstrated in vivo.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Endotoxinas/uso terapêutico , Nanopartículas/uso terapêutico , Nanotecnologia/métodos , Neoplasias/terapia , Radioterapia/métodos , Adenocarcinoma/terapia , Repetição de Anquirina , Neoplasias da Mama/terapia , Linhagem Celular Tumoral , Feminino , Humanos , Neoplasias/diagnóstico por imagem , Pseudomonas aeruginosa , Cintilografia/métodos , Receptor ErbB-2/metabolismo , Proteínas Recombinantes , Radioisótopos de Ítrio/uso terapêutico
10.
J Biosci ; 43(2): 407-416, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29872027

RESUMO

Parasporins, a class of non-insecticidal crystal proteins of Bacillus thuringiensis (Bt) are being explored as promising anticancer agents due to their specific toxicity to cancer cells. The present study has identified 25 Bt isolates harbouring parasporin genes from Western Ghats region, the hotspot of biodiversity in India. Among these, the isolate, KAU 41 (Kerala Agricultural University isolate 41) contained non-hemolytic homogenous crystals showing specific cytotoxicity towards cancer cells. SDS-PAGE analysis of this crystal, isolated by aqueous biphasic separation, revealed a 31 kDa sized peptide. The N-terminal sequence deciphered in BLAST analysis showed homology to a hypothetical Bt protein. Upon proteolysis, a 29 kDa active peptide was generated which exhibited heterogenic cytotoxic spectrum on various cancer cells. HeLa cells were highly susceptible to this peptide with IC 50 1 lg/mL and showed characteristics of apoptosis. RT-qPCR analysis revealed the overexpression of APAF1, caspase 3 and 9 by 14.9, 8 and 7.4 fold, respectively which indicates the activation of intrinsic pathway of apoptosis. However, at higher concentrations of peptide (greater than 3 lg/mL), necrotic death was prominent. The results suggest that the 31 kDa protein from Bt isolate, KAU 41 is a parasporin that may have high therapeutic potential.


Assuntos
Apoptose/efeitos dos fármacos , Endotoxinas/genética , Endotoxinas/isolamento & purificação , Neoplasias/tratamento farmacológico , Antineoplásicos/química , Antineoplásicos/uso terapêutico , Bacillus thuringiensis/química , Endotoxinas/química , Endotoxinas/uso terapêutico , Células HeLa , Humanos , Índia/epidemiologia , Neoplasias/genética , Neoplasias/patologia
11.
Int J Parasitol Drugs Drug Resist ; 8(2): 287-294, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29772478

RESUMO

Hookworms are intestinal nematode parasites that infect nearly half a billion people and are globally one of the most important contributors to iron-deficiency anemia. These parasites have significant impacts in developing children, pregnant women and working adults. Of all the soil-transmitted helminths or nematodes (STNs), hookworms are by far the most important, with disease burdens conservatively estimated at four million DALYs (Disability-Adjusted Life Years) and with productivity losses of up to US$139 billion annually. To date, mainly one drug, albendazole is used for hookworm therapy in mass drug administration, which has on average ∼80% cure rate that is lower (<40%) in some places. Given the massive numbers of people needing treatment, the threat of parasite resistance, and the inadequacy of current treatments, new and better cures against hookworms are urgently needed. Cry5B, a pore-forming protein produced by the soil bacterium Bacillus thuringiensis (Bt) has demonstrated good efficacy against Ancylostoma ceylanicum hookworm infections in hamsters. Here we broaden studies of Cry5B to include tests against infections of Ancylostoma caninum hookworms in dogs and against infections of the dominant human hookworm, Necator americanus, in hamsters. We show that Cry5B is highly effective against all hookworm parasites tested in all models. Neutralization of stomach acid improves Cry5B efficacy, which will aid in practical application of Cry5B significantly. Importantly, we also demonstrate that the anti-nematode therapeutic efficacy of Cry5B is independent of the host immune system and is not itself negated by repeated dosing. This study indicates that Bt Cry5B is a pan-hookworm anthelmintic with excellent properties for use in humans and other animals.


Assuntos
Ancylostomatoidea/efeitos dos fármacos , Anti-Helmínticos/uso terapêutico , Bacillus thuringiensis/química , Proteínas de Bactérias/uso terapêutico , Endotoxinas/uso terapêutico , Proteínas Hemolisinas/uso terapêutico , Infecções por Uncinaria/tratamento farmacológico , Ancylostoma/efeitos dos fármacos , Ancilostomíase/tratamento farmacológico , Ancilostomíase/parasitologia , Animais , Anti-Helmínticos/administração & dosagem , Toxinas de Bacillus thuringiensis , Proteínas de Bactérias/administração & dosagem , Cricetinae , Cães , Endotoxinas/administração & dosagem , Proteínas Hemolisinas/administração & dosagem , Enteropatias Parasitárias/tratamento farmacológico , Necator americanus/efeitos dos fármacos , Necatoríase/tratamento farmacológico , Necatoríase/parasitologia
12.
J Control Release ; 262: 259-272, 2017 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-28713041

RESUMO

Previous studies showed that magnetic hyperthermia could efficiently destroy tumors both preclinically and clinically, especially glioma. However, antitumor efficacy remained suboptimal and therefore required further improvements. Here, we introduce a new type of nanoparticles synthesized by magnetotactic bacteria, called magnetosomes, with improved properties compared with commonly used chemically synthesized nanoparticles. Indeed, mice bearing intracranial U87-Luc glioma tumors injected with 13µg of nanoparticles per mm3 of tumor followed by 12 to 15 of 30min alternating magnetic field applications displayed either full tumor disappearance in 40% of mice or no tumor regression using magnetosomes or chemically synthesized nanoparticles, respectively. Magnetosome superior antitumor activity could be explained both by a larger production of heat and by endotoxins release under alternating magnetic field application. Most interestingly, this behavior was observed when magnetosomes occupied only 10% of the whole tumor volume, which suggests that an indirect mechanism, such as an immune reaction, takes part in tumor regression. This is desired for the treatment of infiltrating tumors, such as glioma, for which whole tumor coverage by nanoparticles can hardly be achieved.


Assuntos
Neoplasias Encefálicas/terapia , Glioma/terapia , Magnetossomos , Animais , Apoptose/efeitos dos fármacos , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Preparações de Ação Retardada/administração & dosagem , Preparações de Ação Retardada/uso terapêutico , Endotoxinas/administração & dosagem , Endotoxinas/uso terapêutico , Compostos Férricos/metabolismo , Temperatura Alta , Humanos , Campos Magnéticos , Magnetospirillum/metabolismo , Camundongos , Nanopartículas/metabolismo , Carga Tumoral/efeitos dos fármacos
13.
Panminerva Med ; 59(2): 173-187, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28001024

RESUMO

Recent data have shown that the host-intestinal microbiota interaction is intrinsically linked with overall health. Chronic kidney disease (CKD) could influence intestinal microbiota and gut dysbiosis is also considered as a cause of progression of kidney disease. An increasing body of evidence indicates that dysbiosis is a key contributor of uremic retention solutes (URS) accumulating in patients with CKD. The discovery of the kidney-gut axis has created new therapeutic opportunities for nutritional intervention in order to prevent adverse outcomes. One of these strategies is prebiotics, which refers to nondigestible food ingredients or substances that beneficial affect growth and/or activity of limited health-promoting bacteria in the gastrointestinal tract. The influence of prebiotics on the production and concentration of URS have been investigated in various animal and human CKD studies. However, to date, there is still paucity of high-quality intervention trials. Randomized controlled trials and adequately powered intervention studies are needed before recommending prebiotics in clinical practice. This review will outline the interconnection between CKD progression, dysbiosis and URS production and will discuss mechanisms of action and efficacy of prebiotics as a new CKD management tool, with a particular emphasis on URS generation.


Assuntos
Microbioma Gastrointestinal , Falência Renal Crônica/microbiologia , Rim/efeitos dos fármacos , Prebióticos , Uremia/tratamento farmacológico , Animais , Progressão da Doença , Disbiose , Endotoxinas/uso terapêutico , Trato Gastrointestinal , Homeostase , Humanos , Inflamação , Falência Renal Crônica/terapia , Microbiota , Probióticos , Insuficiência Renal Crônica/tratamento farmacológico
14.
Zhonghua Gan Zang Bing Za Zhi ; 24(10): 767-771, 2016 Oct 20.
Artigo em Chinês | MEDLINE | ID: mdl-27938563

RESUMO

Objective: To investigate the effect of nicotinic acetylcholine receptor α7 (α7nAChR) subunit gene on liver inflammation in mice with nonalcoholic steatohepatitis (NASH) and related mechanisms. Methods: C57BL/6J mice and α7nAChR gene knockout mice were fed for 24 weeks to establish the NASH model, and the mice were sacrificed to isolate and culture the primary liver macrophages. After the treatment with nicotine and endotoxin, ELISA was used to measure the levels of the inflammatory factors interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) in supernatant; indirect immunofluorescence assay and Western blot were used to observe the effect on the NF-κB signaling pathway, and quantitative PCR was used to measure the mRNA expression of Toll-like receptor-4 (TLR-4) in macrophages. An analysis of variance was used for comparison of means between multiple groups. Results: The results of ELISA showed that compared with the endotoxin+nicotine group of C57 NASH mice, the endotoxin+nicotine group of gene knockout NASH mice had significantly higher levels of IL-6 and TNF-α in supernatant (IL-6: 1 599±65 pg/ml vs 1 465±45 pg/ml, P < 0.05; TNF-α: 1 567±66 pg/ml vs 1 433±50 pg/ml, P < 0.05). The results of Western blot showed that compared with the endotoxin+nicotine group of C57 NASH mice, the endotoxin+nicotine group of gene knockout NASH mice had significantly higher relative protein expression of phosphorylated NF-κB and TLR-4 (NF-κB: 69 425±600 vs 51 133±200, P < 0.05; TLR-4: 93 387±684 vs 64 198±630, P < 0.05). The results of indirect immunofluorescence assay showed that the endotoxin+nicotine group of gene knockout NASH mice had a significantly higher fluorescence intensity of NF-κB than the endotoxin+nicotine group of C57 NASH mice. The results of PCR showed that the endotoxin+nicotine group of gene knockout NASH mice had significantly higher relative mRNA expression of TLR-4 than the endotoxin+nicotine group of C57 NASH mice (4.13±0.13 vs 2.93±0.14, P < 0.05). Conclusion: The α7nAChR gene knockout can aggravate the degree of inflammatory reaction in NASH, and its mechanism may be related to the fact that the NF-κB signaling pathway cannot be inhibited, which aggravates inflammatory reaction.


Assuntos
Anti-Inflamatórios/uso terapêutico , Endotoxinas/uso terapêutico , Inflamação , Fígado/efeitos dos fármacos , Nicotina/uso terapêutico , Agonistas Nicotínicos/uso terapêutico , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Receptor Nicotínico de Acetilcolina alfa7/agonistas , Animais , Modelos Animais de Doenças , Hepatite , Inflamação/tratamento farmacológico , Inflamação/imunologia , Interleucina-6/imunologia , Fígado/patologia , Camundongos , Camundongos Endogâmicos C57BL , NF-kappa B , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/imunologia , Fosforilação , Transdução de Sinais , Fator de Necrose Tumoral alfa/imunologia , Receptor Nicotínico de Acetilcolina alfa7/imunologia
15.
Rev Mal Respir ; 33(3): 261-3, 2016 Mar.
Artigo em Francês | MEDLINE | ID: mdl-26163393

RESUMO

INTRODUCTION: Lipopolysaccharide is a component of the outer membrane of gram-negative bacteria. It plays an important role in asthma as an adjuvant to allergens in activating the airway epithelium. CASE REPORT: Following treatment of a cutaneous mycosis by injection of endotoxin from Salmonella (Pyrogenalum), a 49-year-old non-smoking man developed an acute bronchitis followed by persistent cough, sometimes productive of sputum. Clinical examination was unremarkable. Lung function tests showed airway obstruction, FEV1 54% predicted, partly reversible with salbutamol, and exhaled NO was increased to 73.5 ppb. There was a moderate blood eosinophilia ranging from 540 to 890 per mm(3) (7.4 to 9.6%). Lung CT scan showed no parenchymal or bronchial abnormalities, and ENT examination showed nasal polyposis. CONCLUSION: Besides its critical adjuvant role in the development of asthma when inhaled, this case suggests that endotoxin can also provoke asthma when administered systemically.


Assuntos
Asma/induzido quimicamente , Endotoxinas/efeitos adversos , Eosinofilia Pulmonar/induzido quimicamente , Asma/complicações , Endotoxinas/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Micoses/tratamento farmacológico , Eosinofilia Pulmonar/complicações
16.
J Biomed Mater Res A ; 103(11): 3441-8, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25904112

RESUMO

OBJECTIVE: This study aimed to elucidate the therapeutic effects of intra-articular administration of ultra-purified low endotoxin alginate (UPLE-alginate) on osteoarthritis (OA) using a canine anterior cruciate ligament transection (ACLT) model. DESIGN: We used 20 beagle dogs. ACLT was performed on the left knee of each dog and a sham operation was performed on the right knee as a control. All animals were randomly divided into the control (saline) and therapeutic (UPLE-alginate) groups. Animals in the control and therapeutic groups received weekly injections with 0.7 mL normal saline or 0.7 mL 0.5% UPLE-alginate, respectively, from 0 to 3 weeks after ACLT or sham operation. At 9 weeks after ACLT, the knee joints of all animals were observed using arthroscopy. All animals were euthanized at 14 weeks after ACLT and evaluated using morphologic assessment, histologic assessment, and biomechanical testing. RESULTS: Arthroscopic findings showed intact cartilage surface in both groups. Morphologic findings in the therapeutic group showed milder degeneration compared with those of the control group, but there were no significant differences between groups. Histologic scores of the medial femoral condyle (MFC) and lateral femoral condyle (LFC) were better in the therapeutic group than the control group (MFC: p = 0.009, LFC: p = 0.009). Joint lubrication did not differ significantly between groups. CONCLUSION: Intra-articular administration of UPLE-alginate in the early stage of OA slowed disease progression in canines. UPLE-alginate may have potential as a therapeutic agent for OA patients and reduce the number of patients who need to undergo total joint arthroplasty.


Assuntos
Alginatos/administração & dosagem , Alginatos/uso terapêutico , Endotoxinas/administração & dosagem , Endotoxinas/uso terapêutico , Osteoartrite/tratamento farmacológico , Alginatos/farmacologia , Animais , Ligamento Cruzado Anterior/diagnóstico por imagem , Ligamento Cruzado Anterior/cirurgia , Artroscopia , Cartilagem Articular/efeitos dos fármacos , Cartilagem Articular/patologia , Modelos Animais de Doenças , Cães , Endotoxinas/farmacologia , Fêmur/efeitos dos fármacos , Fêmur/cirurgia , Fricção , Ácido Glucurônico/administração & dosagem , Ácido Glucurônico/farmacologia , Ácido Glucurônico/uso terapêutico , Ácidos Hexurônicos/administração & dosagem , Ácidos Hexurônicos/farmacologia , Ácidos Hexurônicos/uso terapêutico , Injeções Intra-Articulares , Articulações/efeitos dos fármacos , Lubrificação , Osteoartrite/patologia , Osteoartrite/cirurgia , Radiografia
17.
J BUON ; 20(1): 5-16, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25778289

RESUMO

In 1999 Mizuki and co-authors studied for the first time the parasporal inclusion proteins extracted from B. thuringiensis strains (a Gram-positive, soil-dwelling bacterium) for cytotoxic activity against human leukaemia T-cells. Later some other proteins with this unusual property to recognize human leukemic cells were isolated from this strain of bacteria and named parasporins. At present 6 types of parasporins are identified and characterized. This review summarizes the properties of these new potentially useful antitumor agents of natural origin. Various types of parasporins possess unique cytotoxic mechanisms against cancer cells. The cytotoxic activity for cancer cells makes parasporins possible candidates for anticancer agents in clinical oncology. Recently, genetic engineering was applied for the production of parasporins and the gene responsible for the production of the proteins was expressed in E. coli. However, there are virtually no data regarding the cytotoxic (antitumor) activity of parasporins in vivo. These relatively new cytotoxic proteins warrant further investigation, especially in rodents, for possible application in clinical oncology.


Assuntos
Antineoplásicos/uso terapêutico , Bacillus thuringiensis/metabolismo , Produtos Biológicos/uso terapêutico , Endotoxinas/uso terapêutico , Neoplasias/tratamento farmacológico , Animais , Antineoplásicos/efeitos adversos , Antineoplásicos/metabolismo , Bacillus thuringiensis/genética , Produtos Biológicos/efeitos adversos , Produtos Biológicos/metabolismo , Endotoxinas/efeitos adversos , Endotoxinas/biossíntese , Endotoxinas/genética , Endotoxinas/isolamento & purificação , Engenharia Genética , Humanos , Neoplasias/patologia
18.
PLoS Negl Trop Dis ; 7(6): e2263, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23818995

RESUMO

Ascaris suum and Ascaris lumbricoides are two closely related geo-helminth parasites that ubiquitously infect pigs and humans, respectively. Ascaris suum infection in pigs is considered a good model for A. lumbricoides infection in humans because of a similar biology and tissue migration to the intestines. Ascaris lumbricoides infections in children are associated with malnutrition, growth and cognitive stunting, immune defects, and, in extreme cases, life-threatening blockage of the digestive tract and aberrant migration into the bile duct and peritoneum. Similar effects can be seen with A. suum infections in pigs related to poor feed efficiency and performance. New strategies to control Ascaris infections are needed largely due to reduced treatment efficacies of current anthelmintics in the field, the threat of resistance development, and the general lack of new drug development for intestinal soil-transmitted helminths for humans and animals. Here we demonstrate for the first time that A. suum expresses the receptors for Bacillus thuringiensis crystal protein and novel anthelmintic Cry5B, which has been previously shown to intoxicate hookworms and which belongs to a class of proteins considered non-toxic to vertebrates. Cry5B is able to intoxicate A. suum larvae and adults and triggers the activation of the p38 mitogen-activated protein kinase pathway similar to that observed with other nematodes. Most importantly, two moderate doses of 20 mg/kg body weight (143 nM/kg) of Cry5B resulted in a near complete cure of intestinal A. suum infections in pigs. Taken together, these results demonstrate the excellent potential of Cry5B to treat Ascaris infections in pigs and in humans and for Cry5B to work effectively in the human gastrointestinal tract.


Assuntos
Anti-Helmínticos/uso terapêutico , Ascaríase/veterinária , Ascaris suum/efeitos dos fármacos , Ascaris suum/fisiologia , Bacillus thuringiensis/metabolismo , Proteínas de Bactérias/uso terapêutico , Endotoxinas/uso terapêutico , Proteínas Hemolisinas/uso terapêutico , Doenças dos Suínos/tratamento farmacológico , Animais , Anti-Helmínticos/isolamento & purificação , Anti-Helmínticos/farmacologia , Ascaríase/tratamento farmacológico , Ascaríase/parasitologia , Toxinas de Bacillus thuringiensis , Proteínas de Bactérias/isolamento & purificação , Proteínas de Bactérias/farmacologia , Endotoxinas/isolamento & purificação , Endotoxinas/farmacologia , Feminino , Proteínas Hemolisinas/isolamento & purificação , Proteínas Hemolisinas/farmacologia , Larva/efeitos dos fármacos , Larva/fisiologia , Suínos , Doenças dos Suínos/parasitologia , Resultado do Tratamento
19.
Cancer Epidemiol ; 37(5): 528-33, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23692704

RESUMO

Reduced rates of lung cancer have been observed in several occupational groups exposed to high levels of organic dusts contaminated by endotoxin. The underlying anti-neoplastic mechanism of endotoxin may be an increased secretion of endogenous anti-neoplastic mediators and activation of the toll-like receptors (TLR). A detoxified endotoxin derivative, Monophosphoryl Lipid A (MPL(®)) is marketed in Europe since 1999 as part of the adjuvant systems in allergy vaccines for treatment of allergic rhino-conjunctivitis and allergic asthma. Over 200,000 patients have used them to date (nearly 70% in Germany). Since detailed exposure (MPL(®) dose and timing of administration) and individual data are potentially available, an observational follow-up study could be conducted in Germany to investigate the protective effect of MPL(®) against cancer, comparing cancer incidence in two groups of patients with allergic rhinitis: those treated with allergoids plus MPL(®) and those treated with a vaccine including the same allergoids but not MPL(®). The protective effect of MPL(®) could be quantified in ever and never smokers. If this proposed observational study provides evidence of protective effects, MPL(®) could be immediately used as a chemo-preventive agent since it is already in use as adjuvant in human vaccines against cancer.


Assuntos
Anticarcinógenos/farmacologia , Endotoxinas/farmacologia , Neoplasias/prevenção & controle , Anticarcinógenos/uso terapêutico , Endotoxinas/uso terapêutico , Humanos , Lipídeo A/análogos & derivados , Lipídeo A/farmacologia , Lipídeo A/uso terapêutico , Neoplasias/epidemiologia , Doenças Profissionais/epidemiologia , Doenças Profissionais/prevenção & controle , Exposição Ocupacional/efeitos adversos , Exposição Ocupacional/estatística & dados numéricos
20.
Mediators Inflamm ; 2012: 684274, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22665953

RESUMO

Following the discovery of endotoxins by Richard Pfeiffer, such bacterial product was associated to many severe disorders produced by an overwhelming inflammatory response and often resulting in endotoxic shock and multiple organ failure. However, recent clinical and basic sciences investigations claimed some beneficial roles of typical as well as atypical endotoxins. The aim of this paper is to focus on recent data supporting a beneficial activity of both typical and atypical endotoxins. Such novel perspective looks promising for development of new drugs for prevention and therapy of several human diseases.


Assuntos
Lipopolissacarídeos/toxicidade , Lipopolissacarídeos/uso terapêutico , Adjuvantes Imunológicos , Endotoxinas/química , Endotoxinas/imunologia , Endotoxinas/uso terapêutico , Endotoxinas/toxicidade , Humanos , Lipopolissacarídeos/química , Lipopolissacarídeos/imunologia , Vacinas/química , Vacinas/imunologia
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