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1.
Mol Neurobiol ; 2024 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-38308667

RESUMO

Central nervous system (CNS) injuries induce cell death and consequently the release of myelin and other cellular debris. Microglia as well as hematogenous macrophages actively collaborate to phagocyte them and undergo their degradation. However, myelin accumulation persists in the lesion site long after the injury with detrimental effects on axonal regeneration. This might be due to the presence of inhibitors of phagocytosis in the injury site. As we recently published that some proinflammatory stimuli, like interferon-γ (IFNγ) and lipopolysaccharide (LPS), inhibit myelin phagocytosis in macrophages, we have now studied the signaling pathways involved. A phagocytosis assay in Raw264.7 macrophages and N13 microglia cell lines with labeled myelin was developed with the pHrodo reagent that emits fluorescence in acidic cellular compartments (e.g.lysosomes). Pharmacological inhibition of Janus kinases (Jak) with Brepocitinib restored myelin phagocytosis and rescued the expression of genes related to phagocytosis, like triggering receptor expressed on myeloid cells 2 (TREM2), induced by IFNγ or LPS. In addition, while pharmacological inhibition of the signal transducer and activator of transcription 3 (STAT3) rescued myelin phagocytosis and the expression of phagocytosis related genes in the presence of LPS, it did not have any effect on IFNγ-treated cells. Our results show that Jak pathways participate in the inhibition of myelin phagocytosis by IFNγ and LPS. They also indicate that the resolution of inflammation is important for the clearance of cellular debris by macrophages and subsequent regenerative processes.

2.
Int J Mol Sci ; 25(3)2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38338827

RESUMO

The treatment of spinal cord injury (SCI) with uncultivated human bone marrow-derived stromal cells (bmSCs) prepared by negative selection has been proposed to be therapeutically superior to treatment with stem cells that were expanded in vitro. To explore their use in clinical trials, we studied the functional effects of delayed application at 7 days after SCI by testing different doses of bmSCs. Spinal cord contusion injury was induced in adult male Wistar rats at the thoracic level T9. Human bmSCs were prepared by negative selection without expansion in vitro (NeuroCellsTM). Treatment consisted of one 150 µL injection into the cisterna magna containing 0.5 or 2.5 million fresh bmSCs or 2.5 million bmSCs. The recovery of motor functions was evaluated during a surveillance period of six weeks (6 W), during which spinal cords were assessed histologically. Treatment resulted in a significant, dose-dependent therapeutic effect on the recovery of motor performance. The histological analysis revealed a lower degree of axonal degeneration and better survival of neurons and oligodendrocytes in bmSCs treated rats. Our results support delayed intrathecal application of bmSCs prepared by negative selection without expansion in vitro as a treatment of SCI.


Assuntos
Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Traumatismos da Medula Espinal , Ratos , Humanos , Masculino , Animais , Ratos Wistar , Medula Óssea/patologia , 60469 , Traumatismos da Medula Espinal/patologia , Medula Espinal/patologia , Células-Tronco Mesenquimais/fisiologia , Recuperação de Função Fisiológica , Transplante de Células-Tronco Mesenquimais/métodos , Células Estromais/patologia
3.
bioRxiv ; 2023 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-37961209

RESUMO

Diet can protect from autoimmune disease; however, whether diet acts via the host and/or microbiome remains unclear. Here, we use a ketogenic diet (KD) as a model to dissect these complex interactions. A KD rescued the experimental autoimmune encephalomyelitis (EAE) mouse model of multiple sclerosis in a microbiota-dependent fashion. Dietary supplementation with a single KD-dependent host metabolite (ß-hydroxybutyrate, ßHB) rescued EAE whereas transgenic mice unable to produce ßHB in the intestine developed more severe disease. Transplantation of the ßHB-shaped gut microbiota was protective. Lactobacillus sequence variants were associated with decreased T helper 17 (Th17) cell activation in vitro . Finally, we isolated a L. murinus strain that protected from EAE, which was phenocopied by the Lactobacillus metabolite indole lactic acid. Thus, diet alters the immunomodulatory potential of the gut microbiota by shifting host metabolism, emphasizing the utility of taking a more integrative approach to study diet-host-microbiome interactions.

4.
J Neurochem ; 164(4): 454-467, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36409000

RESUMO

Bile acids, which are synthesized in liver and colon, facilitate the digestion of dietary lipids. In addition to this metabolic function, they also act as molecular signals with activities in the nervous system. These are mediated primarily by a G-protein-coupled bile acid receptor (known as TGR5). Preceded by a long tradition in Chinese medicine, bile acids are now being investigated as therapeutic options in several neuropathologies. Specifically, one bile acid, tauroursodeoxycholic acid (TUDCA), which passes the blood-brain barrier and shows anti-inflammatory and anti-apoptotic effects, has been tested in animal models of spinal cord injury (SCI). In this review, we discuss the evidence for a therapeutic benefit in these preclinical experiments. At the time of writing, 12 studies with TGR5 agonists have been published that report functional outcomes with rodent models of SCI. Most investigations found cytoprotective effects and benefits regarding the recovery of sensorimotor function in the subacute phase. When TUDCA was applied in a hydrogel into the lesion site, a significant improvement was obtained at 2 weeks after SCI. However, no lasting improvements with TUDCA treatment were found, when animals were assessed in later, chronic stages. A combination of TUDCA with stem cell injection failed to improve the effect of the cellular treatment. We conclude that the evidence does not support the use of TUDCA as a treatment of SCI. Nevertheless, cytoprotective effects suggest that different modes of application or combinatorial therapies might still be explored.


Assuntos
Traumatismos da Medula Espinal , Ácido Tauroquenodesoxicólico , Animais , Ácido Tauroquenodesoxicólico/farmacologia , Ácido Tauroquenodesoxicólico/uso terapêutico , Traumatismos da Medula Espinal/patologia , Modelos Animais , Receptores Acoplados a Proteínas G/fisiologia
5.
Nat Commun ; 13(1): 7624, 2022 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-36494336

RESUMO

Eggerthella lenta is a prevalent human gut Actinobacterium implicated in drug, dietary phytochemical, and bile acid metabolism and associated with multiple human diseases. No genetic tools are currently available for the direct manipulation of E. lenta. Here, we construct shuttle vectors and develop methods to transform E. lenta and other Coriobacteriia. With these tools, we characterize endogenous E. lenta constitutive and inducible promoters using a reporter system and construct inducible expression systems, enabling tunable gene regulation. We also achieve genome editing by harnessing an endogenous type I-C CRISPR-Cas system. Using these tools to perform genetic knockout and complementation, we dissect the functions of regulatory proteins and enzymes involved in catechol metabolism, revealing a previously unappreciated family of membrane-spanning LuxR-type transcriptional regulators. Finally, we employ our genetic toolbox to study the effects of E. lenta genes on mammalian host biology. By greatly expanding our ability to study and engineer gut Coriobacteriia, these tools will reveal mechanistic details of host-microbe interactions and provide a roadmap for genetic manipulation of other understudied human gut bacteria.


Assuntos
Actinobacteria , Animais , Humanos , Actinobacteria/metabolismo , Bactérias/metabolismo , Eubacterium/metabolismo , Fatores de Transcrição/metabolismo , Sistemas CRISPR-Cas/genética , Mamíferos/metabolismo
6.
Biomedicines ; 10(7)2022 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-35884805

RESUMO

The bile acid tauroursodeoxycholic acid (TUDCA) reduces cell death under oxidative stress and inflammation. Implants of bone marrow-derived stromal cells (bmSC) are currently under investigation in clinical trials of spinal cord injury (SCI). Since cell death of injected bmSC limits the efficacy of this treatment, the cytoprotective effect of TUDCA may enhance its benefit. We therefore studied the therapeutic effect of TUDCA and its use as a combinatorial treatment with human bmSC in a rat model of SCI. A spinal cord contusion injury was induced at thoracic level T9. Treatment consisted of i.p. injections of TUDCA alone or in combination with one injection of human bmSC into the cisterna magna. The recovery of motor functions was assessed during a surveillance period of six weeks. Biochemical and histological analysis of spinal cord tissue confirmed the anti-inflammatory activity of TUDCA. Treatment improved the recovery of autonomic bladder control and had a positive effect on motor functions in the subacute phase, however, benefits were only transient, such that no significant differences between vehicle and TUDCA-treated animals were observed 1-6 weeks after the lesion. Combinatorial treatment with TUDCA and bmSC failed to have an additional effect compared to treatment with bmSC only. Our data do not support the use of TUDCA as a treatment of SCI.

8.
Sci Rep ; 12(1): 1459, 2022 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-35087114

RESUMO

Glycolysis is the metabolic pathway that converts glucose into pyruvate. Central nervous system (CNS) pathologies, such as spinal cord injury (SCI) and ischemia, are accompanied by an increase of the glycolytic pathway in the damaged areas as part of the inflammatory response. Pyruvate kinase is a key glycolytic enzyme that converts phosphoenolpyruvate and ADP to pyruvate and ATP. The protein has two isoforms, PKM1 and PKM2, originated from the same gene. As a homodimer, PKM2 loses the pyruvate kinase activity and acts as a transcription factor that regulates the expression of target genes involved in glycolysis and inflammation. After SCI, resident microglia and hematogenous macrophages are key inducers of the inflammatory response with deleterious effects. Activation of the bile acid receptor TGR5 inhibits the pro-inflammatory NFκB pathway in microglia and macrophages. In the present study we have investigated whether bile acids affect the expression of glycolytic enzymes and their regulation by PKM2. Bacterial lipopolysaccharide (LPS) induced the expression of PKM1, PKM2 and its target genes in primary cultures of microglial and Raw264.7 macrophage cells. SCI caused an increase of PKM2 immunoreactivity in macrophages after SCI. Pretreatment with tauroursodeoxycholic acid (TUDCA) or taurolithocholic acid (TLCA) reduced the expression of PKM2 and its target genes in cell cultures. Similarly, after SCI, TUDCA treatment reduced the expression of PKM2 in the lesion center. These results confirm the importance of PKM2 in the inflammatory response in CNS pathologies and indicate a new mechanism of bile acids as regulators of PKM2 pathway.


Assuntos
Ácidos e Sais Biliares/metabolismo , Microglia/patologia , Doenças Neuroinflamatórias/imunologia , Piruvato Quinase/metabolismo , Traumatismos da Medula Espinal/imunologia , Animais , Modelos Animais de Doenças , Glicólise , Humanos , Isoenzimas/genética , Isoenzimas/metabolismo , Lipopolissacarídeos/imunologia , Macrófagos , Masculino , Camundongos , Microglia/imunologia , Doenças Neuroinflamatórias/patologia , Cultura Primária de Células , Piruvato Quinase/genética , Células RAW 264.7 , Ratos , Receptores Acoplados a Proteínas G/metabolismo , Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/patologia
9.
J Cell Physiol ; 237(2): 1455-1470, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34705285

RESUMO

Spinal cord injury (SCI) causes cell death and consequently the breakdown of axons and myelin. The accumulation of myelin debris at the lesion site induces inflammation and blocks axonal regeneration. Hematogenous macrophages contribute to the removal of myelin debris. In this study, we asked how the inflammatory state of macrophages affects their ability to phagocytose myelin. Bone marrow-derived macrophages (BMDM) and Raw264.7 cells were stimulated with lipopolysaccharides (LPS) or interferon gamma (IFNγ), which induce inflammatory stress, and the endocytosis of myelin was examined. We found that activation of the TLR4-NFκB pathway reduced myelin uptake by BMDM, while IFNγ-Jak/STAT1 signaling did not. Since bile acids regulate lipid metabolism and in some cases reduce inflammation, our second objective was to investigate whether myelin clearance could be improved with taurolithocholic acid (TLCA), tauroursodeoxycholic acid or hyodeoxycholic acid. In BMDM only TLCA rescued myelin phagocytosis, when this activity was suppressed by LPS. Inhibition of protein kinase A blocked the effect of TLCA, while an agonist of the farnesoid X receptor did not rescue phagocytosis, implicating TGR5-PKA signaling in the effect of TLCA. To shed light on the mechanism, we measured whether TLCA affected the expression of CD36, triggering receptor on myeloid cells-2 (TREM2), and Gas6, which are known to be involved in phagocytosis and affected by inflammatory stimuli. Concomitant with an increase in expression of tumour necrosis factor alpha, LPS reduced expression of TREM2 and Gas6 in BMDM, and TLCA significantly diminished this downregulation. These findings suggest that activation of bile acid receptors may be used to improve myelin clearance in neuropathologies.


Assuntos
Lipopolissacarídeos , Ácido Taurolitocólico , Humanos , Inflamação/patologia , Lipopolissacarídeos/metabolismo , Lipopolissacarídeos/farmacologia , Macrófagos/metabolismo , Bainha de Mielina , Fagocitose , Ácido Tauroquenodesoxicólico , Ácido Taurolitocólico/metabolismo , Ácido Taurolitocólico/farmacologia
10.
J Ultrasound ; 25(2): 199-205, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33948886

RESUMO

OBJECTIVE: To present the results of an ultrasound vascular cannulation (UGVC) training program for inexperienced operators using a training model. METHOD: This was a descriptive observational study developed in the paediatric intensive care unit (PICU) of a third-level hospital. Operators received basic theoretical training in the USVC technique, followed by practical training with a model designed for USVC-inexperienced healthcare professionals. RESULTS: The study included 25 healthcare professionals, who carried out a total of 300 ultrasound-guided cannulation procedures (12 per participant) at equidistant sites on the longitudinal axis/in-plane (LA/IP) and the transverse axis/out-of-plane (TA/OP). The mean depth of cannulated vessels was 0.90 (0.34) cm and their mean diameter was 0.41 (0.1) cm. In 41.7% of cases, complete view of the needle (CVN) was accomplished; in 49% of cases, repositioning of the needle/guidewire (RNG) was necessary for successful UGVC. The rate of successful UGVC in the training model was 79.7%. The mean time required for the procedure was 74.70 (73.72) seconds. The time to successful cannulation was 58.72 (56.87) seconds. The mean number of attempts needed until successful UGVC was 1.31 (0.72). Complications were: (a) 26.3% vessel perforation/wrong guidewire positioning (VP/WGP) and (b) 4.3% successful vessel puncture followed by failure to accomplish subsequent cannulation. CONCLUSIONS: Through the present theoretical-practical training program for inexperienced operators using a training model: (a) high success rates and short procedural times were attained; (b) complete view of needle and need for repositioning the needle/guidewire occurred in half of the procedures; and (c) complications occurred in a third of the procedures.


Assuntos
Cateterismo Periférico , Ultrassonografia de Intervenção , Criança , Humanos , Agulhas , Ultrassonografia/métodos , Ultrassonografia de Intervenção/métodos
11.
J Med Ultrasound ; 29(3): 171-175, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34729325

RESUMO

BACKGROUND: The study objective was to evaluate a training program and a training model for pediatric ultrasound-guided vascular cannulation (USGVC) by inexperienced operators. METHODS: An observational descriptive study was conducted at the pediatric intensive care unit of a level-III hospital. The study protocol comprised the following parts: (1) pretraining test; (2) theory and practice training session consisting of an explanation of basic vascular ultrasound concepts plus performing vascular cannulation in a model; (3) posttraining test; and (4) evaluation of the training model. RESULTS: A total of 25 health-care professionals participated in the study. All of them possessed the skills to locate vessels and ultrasound planes, and they performed USGVC using the training model. On a 1-5 scale, the model was rated to have 87.6% fidelity with real pediatric patients; the best regarded aspect of it was utility (93%). Differences were found between pre- and post-training scores: 2.72 ± 0.84 versus 4.60 ± 0.50; P < 0.001 (95% confidence interval: -2.28, -1.47). Altogether, 300 ultrasound-guided cannulation procedures were carried out (12 per participant) distributed along the longitudinal axis in plane and the transverse axis out of plane, with 150 punctures in each of them. The success rate for USGVC in the training model was 79.7%, the mean time for the procedure was 115.6 ± 114.9 s, and the mean time for achieving successful cannulation was 87.69 ± 82.81 s. The mean number of trials needed for successful USGVC was 1.49 ± 0.86. CONCLUSION: After undergoing the theory-practice training, participants: (a) improved their knowledge of ultrasound-guided vascular access; (b) positively evaluated the USGVC training model, in particular its utility and fidelity as compared with cannulation in pediatric patients; and (c) achieved a high USGVC success rate in a relatively short time.

12.
J Cell Physiol ; 236(5): 3929-3945, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33165955

RESUMO

Traumatic injuries of the central nervous system (CNS) are followed by the accumulation of cellular debris including proteins and lipids from myelinated fiber tracts. Insufficient phagocytic clearance of myelin debris influences the pathological process because it induces inflammation and blocks axonal regeneration. We investigated whether ligands of nuclear receptor families retinoic acid receptors (RARs), retinoid X receptors, peroxisome proliferator-activated receptors, lipid X receptors, and farnesoid X receptors increase myelin phagocytosis by murine bone marrow-derived macrophages and Raw264.7 cells. Using in vitro assays with 3,3'-dioctadecyloxacarbocyanine perchlorate- and pHrodo-labeled myelin we found that the transcriptional activator all-trans retinoic acid (RA)enhanced endocytosis of myelin involving the induction of tissue transglutaminase-2. The RAR-dependent increase of phagocytosis was not associated with changes in gene expression of receptors FcγR1, FcγR2b, FcγR3, TREM2, DAP12, CR3, or MerTK. The combination of RA and myelin exposure significantly reduced the expression of M1 marker genes inducible nitric oxide synthase and interleukin-1ß and increased expression of transmembrane proteins CD36 and ABC-A1, which are involved in lipid transport and metabolism. The present results suggest an additional mechanism for therapeutic applications of RA after CNS trauma. It remains to be studied whether endogenous RA-signaling regulates phagocytosis in vivo.


Assuntos
Macrófagos/metabolismo , Bainha de Mielina/metabolismo , Fagocitose , Tretinoína/farmacologia , Animais , Regulação da Expressão Gênica/efeitos dos fármacos , Inflamação/genética , Inflamação/patologia , Macrófagos/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microglia/efeitos dos fármacos , Microglia/metabolismo , Bainha de Mielina/efeitos dos fármacos , Fagocitose/efeitos dos fármacos , Fagocitose/genética , Fenótipo , Células RAW 264.7 , Receptores Citoplasmáticos e Nucleares/agonistas , Receptores Citoplasmáticos e Nucleares/genética , Receptores Citoplasmáticos e Nucleares/metabolismo , Receptores do Ácido Retinoico/agonistas , Receptores do Ácido Retinoico/metabolismo
13.
J Gastroenterol ; 56(1): 78-89, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33159804

RESUMO

BACKGROUND: Wilson disease is an autosomal recessive disorder of copper metabolism caused by mutations in the ATP7B gene. An early diagnosis is crucial to prevent evolution of the disease, as implantation of early therapeutic measures fully prevents its symptoms. As population genetics data predict a higher than initially expected prevalence, it was important to define the basic diagnostic tools to approach population screening. METHODS: A highly genetically homogeneous cohort of 70 patients, belonging to 50 unrelated families, has been selected as a framework to analyze all their clinical, biochemical and genetic characteristics, to define the disease in our population, with an estimated prevalence of 1 in 12,369, and determine the most useful features that reach diagnostic value. RESULTS: Serum ceruloplasmin below 11.5 mg/dL and cupremia below 60 µg/mL, were the best analytical predictors of the disease in asymptomatic individuals, while cupruria or hepatic copper determination were less powerful. Genetic analysis reached a conclusive diagnosis in all 65 patients available for complete testing. Of them, 48 were carriers of at least one p.Leu708Pro mutant allele, with 24 homozygotes. Nine patients carried a promoter deletion mutation, revealing that extended sequencing beyond the ATP7B gene-coding region is essential. All mutations caused hepatic damage since early ages, increasing its severity as diagnosis was delayed, and neurological symptoms appear. CONCLUSION: Serum ceruloplasmin determination followed by genetic screening would reduce costs and favor the prioritization of non-invasive procedures to reach a definitive diagnosis, even for asymptomatic cases.


Assuntos
Ceruloplasmina/metabolismo , ATPases Transportadoras de Cobre/genética , Testes Genéticos/métodos , Degeneração Hepatolenticular/diagnóstico , Programas de Rastreamento/métodos , Adolescente , Adulto , Idoso , Biomarcadores/sangue , Criança , Pré-Escolar , Cobre/metabolismo , Diagnóstico Tardio , Diagnóstico Precoce , Feminino , Marcadores Genéticos , Degeneração Hepatolenticular/sangue , Degeneração Hepatolenticular/epidemiologia , Degeneração Hepatolenticular/genética , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Mutação , Prevalência , Prognóstico , Sensibilidade e Especificidade , Índice de Gravidade de Doença , Espanha/epidemiologia , Adulto Jovem
14.
J Biomed Sci ; 27(1): 35, 2020 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-32066435

RESUMO

BACKGROUND: Spinal cord injury (SCI) is a highly debilitating pathology without curative treatment. One of the most promising disease modifying strategies consists in the implantation of stem cells to reduce inflammation and promote neural regeneration. In the present study we tested a new human bone marrow-derived stromal cell preparation (bmSC) as a therapy of SCI. METHODS: Spinal cord contusion injury was induced in adult male rats at thoracic level T9/T10 using the Infinite Horizon impactor. One hour after lesion the animals were treated with a sub-occipital injection of human bmSC into the cisterna magna. No immune suppression was used. One dose of bmSC consisted, on average, of 2.3 million non-manipulated cells in 100 µL suspension, which was processed out of fresh human bone marrow from the iliac crest of healthy volunteers. Treatment efficacy was compared with intraperitoneal injections of methylprednisolone (MP) and saline. The recovery of motor functions was assessed during a surveillance period of nine weeks. Adverse events as well as general health, weight and urodynamic functions were monitored daily. After this time, the animals were perfused, and the spinal cord tissue was investigated histologically. RESULTS: Rats treated with bmSC did not reject the human implants and showed no sign of sickness behavior or neuropathic pain. Compared to MP treatment, animals displayed better recovery of their SCI-induced motor deficits. There were no significant differences in the recovery of bladder control between groups. Histological analysis at ten weeks after SCI revealed no differences in tissue sparing and astrogliosis, however, bmSC treatment was accompanied with reduced axonal degeneration in the dorsal ascending fiber tracts, lower Iba1-immunoreactivity (IR) close to the lesion site and reduced apoptosis in the ventral grey matter. Neuroinflammation, as evidenced by CD68-IR, was significantly reduced in the MP-treated group. CONCLUSIONS: Human bmSC that were prepared by negative selection without expansion in culture have neuroprotective properties after SCI. Given the effect size on motor function, implantation in the acute phase was not sufficient to induce spinal cord repair. Due to their immune modulatory properties, allogeneic implants of bmSC can be used in combinatorial therapies of SCI.


Assuntos
Inflamação/prevenção & controle , Injeções Intraperitoneais , Injeções Espinhais , Transplante de Células-Tronco Mesenquimais/instrumentação , Regeneração Nervosa/fisiologia , Traumatismos da Medula Espinal/terapia , Humanos , Células-Tronco Mesenquimais/fisiologia
15.
Toxicol Appl Pharmacol ; 377: 114627, 2019 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-31202640

RESUMO

In many neuropathologies activated microglia and macrophages cause neurotoxicity and prolong the inflammatory response. We have previously characterized the glycosphingolipid Neurostatin (Nst), which potentially reduces these detrimental mechanisms. Nst, isolated from mammalian brain, is the GD1b ganglioside with O-acetylation of the outer sialic acid residue. Using the enzyme sialate-O-acetyltransferase (SOAT), we obtained several O-acetylated gangliosides and O-propionylated GD1b (PrGD1b). In the present study we investigated the anti-inflammatory effects of these compounds. Nst and other O-acetylated gangliosides reduced nitrite production in microglial cells which were activated with lipopolysaccharide (LPS), but did not affect nitrite production after their stimulation with interferon gamma (IFNγ). Structure-activity relationship analysis showed that Nst was the most active ganglioside as inhibitor of nitrite production. Its ceramide moiety is essential for this, and both, the O-acetylation and the monosaccharide chain are important for the anti-inflammatory activity of the gangliosides. We also found that Nst reduced iNOS, IL-6 and IL-12 transcription in LPS-induced microglia, likely by inhibiting nuclear localization of NFκB. In co-cultures, Nst reduced neuronal cell death caused by LPS-activated microglia. In vivo, Nst diminished microglia activation in a mouse model of acute neuroinflammation. We propose that Nst and other O-acetylated gangliosides are neuroprotective regulators of microglia activity under both physiological and pathological conditions.


Assuntos
Anti-Inflamatórios/farmacologia , Encefalite/prevenção & controle , Gangliosídeos/farmacologia , Glicoesfingolipídeos/farmacologia , NF-kappa B/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Transdução de Sinais/efeitos dos fármacos , Animais , Linhagem Celular , Lipopolissacarídeos/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microglia/efeitos dos fármacos , Transportadores de Ânions Orgânicos/metabolismo , Ratos , Ratos Wistar
16.
Nanomaterials (Basel) ; 8(8)2018 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-30044386

RESUMO

The synthesis procedure of nanoparticles based on thermal degradation produces organic solvent dispersible iron oxide nanoparticles (OA-IONP) with oleic acid coating and unique physicochemical properties of the core. Some glycosides with hydrophilic sugar moieties bound to oleyl hydrophobic chains have antimitotic activity on cancer cells but reduced in vivo applications because of the intrinsic low solubility in physiological media, and are prone to enzymatic hydrolysis. In this manuscript, we have synthetized and characterized OA-IONP-based micelles encapsulated within amphiphilic bioactive glycosides. The glycoside-coated IONP micelles were tested as Magnetic Resonance Imaging (MRI) contrast agents as well as antimitotics on rat glioma (C6) and human lung carcinoma (A549) cell lines. Micelle antimitotic activity was compared with the activity of the corresponding free glycosides. In general, all OA-IONP-based micellar formulations of these glycosides maintained their anti-tumor effects, and, in one case, showed an unusual therapeutic improvement. Finally, the micelles presented optimal relaxometric properties for their use as T2-weighed MRI contrast agents. Our results suggest that these bioactive hydrophilic nano-formulations are theranostic agents with synergistic properties obtained from two entities, which separately are not ready for in vivo applications, and strengthen the possibility of using biomolecules as both a coating for OA-IONP micellar stabilization and as drugs for therapy.

17.
Arch. argent. pediatr ; 116(3): 204-209, jun. 2018. tab, ilus, graf
Artigo em Inglês, Espanhol | LILACS, BINACIS | ID: biblio-950011

RESUMO

Introducción. La canalización vascular central en niños presenta alta complejidad técnica y dificultades. La ecografía vascular puede facilitar este procedimiento. Objetivo. Describir las características de las canalizaciones vasculares ecoguiadas en el paciente pediátrico crítico. Población y métodos. Las variables de interés registradas prospectivamente fueron los vasos más comúnmente canalizados, su localización, la medición del diámetro/profundidad, la tasa de éxito y las complicaciones presentadas, entre otras. Resultados. En 86 pacientes pediátricos, se realizaron 124 punciones vasculares. Los accesos vasculares fueron la vena femoral (39,7%), seguida de la arteria femoral (27,2%) y la vena yugular interna (14,7%). Los vasos femorales se localizaron a una profundidad de 0,75 ± 0,25 mm con un diámetro medio de 0,31 ± 0,16 mm. La profundidad de los vasos venosos yugulares fue menor (0,64 ± 0,24 mm) y su diámetro global, mayor (0,44 ± 0,19 mm). El número medio de intentos en las canalizaciones vasculares ecoguiadas fue de 2,2 ± 1,3. La tasa de éxito fue del 79% asociada a un mayor diámetro del vaso (0,39 ± 0,20 mm vs. 0,28 ± 0,13 mm, p 0,01) y un menor número de intentos (1,90 ± 1,16 vs. 3,45 ± 1,77, p= 0,001). Las complicaciones, fueron la punción accidental de otro vaso (5,3%) y el desarrollo de un hematoma durante la punción (2,3%). Conclusiones. La canalización vascular ecoguiada en los pacientes pediátricos estudiados permite visualizar los vasos y medir su profundidad y diámetro; presenta una alta tasa de éxito y se asocia a una baja tasa de complicaciones.


Introduction. Central vascular cannulation in children is a highly complex technique and poses many difficulties. Vascular ultrasound can make this procedure easier. Objective. To describe the characteristics of ultrasound-guided vascular cannulation in critically-ill pediatric patients. Population and methods. Outcome measures prospectively recorded were vessels most frequently cannulated, their localization, the measurement of their diameter/depth, the success rate and complications developed, among others. Results. One hundred and twenty four vascular punctures were performed in 86 pediatric patients. Vascular accesses were the femoral vein (39.7%), followed by the femoral artery (27.2%) and the internal jugular vein (14.7%). Femoral vessels were localized at a depth of 0.75 ± 0.25 mm, with a mean diameter of 0.31 ± 0.16 mm. The depth of jugular vein vessels was smaller (0.64 ± 0.24 mm) and their overall diameter, larger (0.44 ± 0.19 mm). The mean number of attempts in ultrasound-guided cannulations was 2.2 ± 1.3. The success rate was 79% and was associated to a larger vessel diameter (0.39 ± 0.20 mm vs. 0.28 ± 0.13 mm, p= 0.01) and a lower number of attempts (1.90 ± 1.16 vs. 3.45 ± 1.77, p= 0.001). Complications were accidental puncture of another vessel (5.3%) and hematoma formation during puncture (2.3%). Conclusions. In the pediatric patients studied, ultrasound-guided vascular cannulation allowed vessel visualization and measurement of their depth and diameter; the success rate was high and it was associated to a low complication rate.


Assuntos
Humanos , Masculino , Feminino , Recém-Nascido , Lactente , Pré-Escolar , Criança , Adolescente , Cateterismo Venoso Central/métodos , Ultrassonografia de Intervenção/métodos , Artéria Femoral/diagnóstico por imagem , Veia Femoral/diagnóstico por imagem , Veias Jugulares/diagnóstico por imagem , Cateterismo Venoso Central/efeitos adversos , Estudos Prospectivos , Avaliação de Resultados em Cuidados de Saúde , Estado Terminal , Hematoma/etiologia , Hematoma/epidemiologia
18.
Arch Argent Pediatr ; 116(3): 204-209, 2018 06 01.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-29756705

RESUMO

INTRODUCTION: Central vascular cannulation in children is a highly complex technique and poses many difficulties. Vascular ultrasound can make this procedure easier. OBJECTIVE: To describe the characteristics of ultrasound-guided vascular cannulation in critically-ill pediatric patients. POPULATION AND METHODS: Outcome measures prospectively recorded were vessels most frequently cannulated, their localization, the measurement of their diameter/depth, the success rate and complications developed, among others. RESULTS: One hundred and twenty four vascular punctures were performed in 86 pediatric patients. Vascular accesses were the femoral vein (39.7%), followed by the femoral artery (27.2%) and the internal jugular vein (14.7%). Femoral vessels were localized at a depth of 0.75 ± 0.25 mm, with a mean diameter of 0.31 ± 0.16 mm. The depth of jugular vein vessels was smaller (0.64 ± 0.24 mm) and their overall diameter, larger (0.44 ± 0.19 mm). The mean number of attempts in ultrasound-guided cannulations was 2.2 ± 1.3. The success rate was 79% and was associated to a larger vessel diameter (0.39 ± 0.20 mm vs. 0.28 ± 0.13 mm, p= 0.01) and a lower number of attempts (1.90 ± 1.16 vs. 3.45 ± 1.77, p= 0.001). Complications were accidental puncture of another vessel (5.3%) and hematoma formation during puncture (2.3%). CONCLUSIONS: In the pediatric patients studied, ultrasound-guided vascular cannulation allowed vessel visualization and measurement of their depth and diameter; the success rate was high and it was associated to a low complication rate.


Introducción. La canalización vascular central en niños presenta alta complejidad técnica y dificultades. La ecografía vascular puede facilitar este procedimiento. Objetivo. Describir las características de las canalizaciones vasculares ecoguiadas en el paciente pediátrico crítico. Población y métodos. Las variables de interés registradas prospectivamente fueron los vasos más comúnmente canalizados, su localización, la medición del diámetro/profundidad, la tasa de éxito y las complicaciones presentadas, entre otras. Resultados. En 86 pacientes pediátricos, se realizaron 124 punciones vasculares. Los accesos vasculares fueron la vena femoral (39,7%), seguida de la arteria femoral (27,2%) y la vena yugular interna (14,7%). Los vasos femorales se localizaron a una profundidad de 0,75 ± 0,25 mm con un diámetro medio de 0,31 ± 0,16 mm. La profundidad de los vasos venosos yugulares fue menor (0,64 ± 0,24 mm) y su diámetro global, mayor (0,44 ± 0,19 mm). El número medio de intentos en las canalizaciones vasculares ecoguiadas fue de 2,2 ± 1,3. La tasa de éxito fue del 79% asociada a un mayor diámetro del vaso (0,39 ± 0,20 mm vs. 0,28 ± 0,13 mm, p 0,01) y un menor número de intentos (1,90 ± 1,16 vs. 3,45 ± 1,77, p= 0,001). Las complicaciones, fueron la punción accidental de otro vaso (5,3%) y el desarrollo de un hematoma durante la punción (2,3%). Conclusiones. La canalización vascular ecoguiada en los pacientes pediátricos estudiados permite visualizar los vasos y medir su profundidad y diámetro; presenta una alta tasa de éxito y se asocia a una baja tasa de complicaciones.


Assuntos
Cateterismo Venoso Central/métodos , Artéria Femoral/diagnóstico por imagem , Veia Femoral/diagnóstico por imagem , Veias Jugulares/diagnóstico por imagem , Ultrassonografia de Intervenção/métodos , Adolescente , Cateterismo Venoso Central/efeitos adversos , Criança , Pré-Escolar , Estado Terminal , Hematoma/epidemiologia , Hematoma/etiologia , Humanos , Lactente , Recém-Nascido , Avaliação de Resultados em Cuidados de Saúde , Estudos Prospectivos
19.
Biomed Res Int ; 2017: 6953156, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28536699

RESUMO

Central nervous system (CNS) injuries, caused by cerebrovascular pathologies or mechanical contusions (e.g., traumatic brain injury, TBI) comprise a diverse group of disorders that share the activation of the integrated stress response (ISR). This pathway is an innate protective mechanism, with encouraging potential as therapeutic target for CNS injury repair. In this review, we will focus on the progress in understanding the role of the ISR and we will discuss the effects of various small molecules that target the ISR on different animal models of CNS injury.


Assuntos
Lesões Encefálicas Traumáticas/fisiopatologia , Sistema Nervoso Central/fisiopatologia , Traumatismos da Medula Espinal/fisiopatologia , Animais , Sistema Nervoso Central/lesões , Humanos , Modelos Animais , Estresse Fisiológico
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