RESUMEN
Myotonic dystrophy type 1 (DM1), the most common form of adult muscular dystrophy, is caused by an abnormal expansion of CTG repeats in the 3' untranslated region of the dystrophia myotonica protein kinase (DMPK) gene. The expanded repeats of the DMPK mRNA form hairpin structures in vitro, which cause misregulation and/or sequestration of proteins including the splicing regulator muscleblind-like 1 (MBNL1). In turn, misregulation and sequestration of such proteins result in the aberrant alternative splicing of diverse mRNAs and underlie, at least in part, DM1 pathogenesis. It has been previously shown that disaggregating RNA foci repletes free MBNL1, rescues DM1 spliceopathy, and alleviates associated symptoms such as myotonia. Using an FDA-approved drug library, we have screened for a reduction of CUG foci in patient muscle cells and identified the HDAC inhibitor, vorinostat, as an inhibitor of foci formation; SERCA1 (sarcoplasmic/endoplasmic reticulum Ca2+-ATPase) spliceopathy was also improved by vorinostat treatment. Vorinostat treatment in a mouse model of DM1 (human skeletal actin-long repeat; HSALR) improved several spliceopathies, reduced muscle central nucleation, and restored chloride channel levels at the sarcolemma. Our in vitro and in vivo evidence showing amelioration of several DM1 disease markers marks vorinostat as a promising novel DM1 therapy.
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Distrofia Miotónica , Empalme del ARN , Vorinostat , Adulto , Animales , Humanos , Ratones , Empalme Alternativo/efectos de los fármacos , Células Musculares/metabolismo , Músculo Esquelético/metabolismo , Distrofia Miotónica/genética , Empalme del ARN/efectos de los fármacos , ARN Mensajero/genética , ATPasas Transportadoras de Calcio del Retículo Sarcoplásmico/metabolismo , Expansión de Repetición de Trinucleótido , Vorinostat/metabolismoRESUMEN
Poly(ADP-ribose) polymerase 1 (PARP-1) is a nuclear enzyme that catalyze the transfer of ADP-ribose units from NAD+ to several target proteins involved in cellular stress responses. Using WRL68 (HeLa derivate) cells, we previously showed that PARP-1 activation induced by oxidative stress after H2O2 treatment lead to depletion of cellular NAD+ and ATP, which promoted cell death. In this work, LC-MS/MS-based phosphoproteomics in WRL68 cells showed that the oxidative damage induced by H2O2 increased the phosphorylation of YAP1, a transcriptional co-activator involved in cell survival, and modified the phosphorylation of other proteins involved in transcription. Genetic or pharmacological inhibition of PARP-1 in H2O2-treated cells reduced YAP1 phosphorylation and degradation and increased cell viability. YAP1 silencing abrogated the protective effect of PARP-1 inhibition, indicating that YAP1 is important for the survival of WRL68 cells exposed to oxidative damage. Supplementation of NAD+ also reduced YAP1 phosphorylation, suggesting that the loss of cellular NAD+ caused by PARP-1 activation after oxidative treatment is responsible for the phosphorylation of YAP1. Finally, PARP-1 silencing after oxidative treatment diminished the activation of the metabolic sensor AMPK. Since NAD+ supplementation reduced the phosphorylation of some AMPK substrates, we hypothesized that the loss of cellular NAD+ after PARP-1 activation may induce an energy stress that activates AMPK. In summary, we showed a new crucial role of PARP-1 in the response to oxidative stress in which PARP-1 activation reduced cell viability by promoting the phosphorylation and degradation of YAP1 through a mechanism that involves the depletion of NAD+.
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Proteínas Adaptadoras Transductoras de Señales/metabolismo , Estrés Oxidativo , Poli(ADP-Ribosa) Polimerasa-1/metabolismo , Factores de Transcripción/metabolismo , Proteínas Quinasas Activadas por AMP/genética , Proteínas Quinasas Activadas por AMP/metabolismo , Proteínas Adaptadoras Transductoras de Señales/genética , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/genética , Células HeLa , Humanos , Peróxido de Hidrógeno/farmacología , NAD/genética , NAD/metabolismo , Fosforilación/efectos de los fármacos , Fosforilación/genética , Poli(ADP-Ribosa) Polimerasa-1/genética , Factores de Transcripción/genética , Proteínas Señalizadoras YAPRESUMEN
Liver disease encompasses pathologies as non-alcoholic fatty liver disease, non-alcoholic steatohepatitis, alcohol liver disease, hepatocellular carcinoma, viral hepatitis, and autoimmune hepatitis. Nowadays, underlying mechanisms associating gut permeability and liver disease development are not well understood, although evidence points to the involvement of intestinal microbiota and their metabolites. Animal studies have shown alterations in Toll-like receptor signaling related to the leaky gut syndrome by the action of bacterial lipopolysaccharide. In humans, modifications of the intestinal microbiota in intestinal permeability have also been related to liver disease. Some of these changes were observed in bacterial species belonging Roseburia, Streptococcus, and Rothia. Currently, numerous strategies to treat liver disease are being assessed. This review summarizes and discusses studies addressed to determine mechanisms associated with the microbiota able to alter the intestinal barrier complementing the progress and advancement of liver disease, as well as the main strategies under development to manage these pathologies. We highlight those approaches that have shown improvement in intestinal microbiota and barrier function, namely lifestyle changes (diet and physical activity) and probiotics intervention. Nevertheless, knowledge about how such modifications are beneficial is still limited and specific mechanisms involved are not clear. Thus, further in-vitro, animal, and human studies are needed.
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Microbioma Gastrointestinal/fisiología , Mucosa Intestinal/fisiología , Hepatopatías/fisiopatología , Animales , Bacterias/metabolismo , Disbiosis/complicaciones , Humanos , Mucosa Intestinal/metabolismo , Hígado/metabolismo , Hepatopatías/microbiología , Hepatopatías Alcohólicas/metabolismo , Microbiota/fisiología , Enfermedad del Hígado Graso no Alcohólico/metabolismoRESUMEN
BACKGROUND AND OBJECTIVE: Neutrophil extracellular traps (NETs) are a recently discovered antimicrobial mechanism used by neutrophils that have been proposed as an intervention in the pathogenesis of periodontitis. The objective of our study was to characterize the expression of NETs in gingival tissues with periodontitis and controls and to compare the expression of these traps in gingival tissue samples of patients with gingivitis and periodontitis. MATERIAL AND METHODS: An observational cross-sectional study was conducted on patients with periodontitis, gingivitis, and controls that needed tooth extraction. Gingival tissue biopsies were gathered after clinical examination and tooth extraction. Electron microscopy and immunofluorescence were performed to characterize NETs, comparing periodontitis and control patients. Immunohistochemical analysis was performed to quantify neutrophil extracellular trap expression through extracellular citrullinated histone H3 and myeloperoxidase in biopsies from patients with gingivitis and periodontitis. RESULTS: Thirteen biopsies were gathered from 13 patients: five gingivitis, six periodontitis, and two controls. Electron microscopy and immunofluorescence imaging showed greater expression of neutrophils present in periodontal inflamed tissue compared with controls. Release of nuclear content to the extracellular space was observed, compatible with the formation of NETs. The expression of citrullinated histone H3 was higher in gingivitis samples than periodontitis samples (P = 0.0106). Myeloperoxidase expression was higher in periodontitis than gingivitis, but without achieving statistical significance. CONCLUSION: Neutrophil extracellular traps were found in tissue samples of periodontitis as extracellular components of chromatin, along with neutrophil enzymes, that were not present in healthy controls. The comparison of NETs expression in periodontitis and gingivitis showed higher expression in gingivitis, associating them to acute phases of the periodontal inflammatory process.
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Trampas Extracelulares , Encía/patología , Gingivitis/patología , Neutrófilos/citología , Periodontitis/patología , Estudios de Casos y Controles , Cromatina , Estudios Transversales , Encía/metabolismo , Gingivitis/metabolismo , Histonas/metabolismo , Humanos , Microscopía Electrónica de Transmisión , Neutrófilos/ultraestructura , Periodontitis/metabolismo , Peroxidasa/metabolismo , Proyectos PilotoRESUMEN
The loss of functional Survival Motor Neuron (SMN) protein due to mutations or deletion in the SMN1 gene causes autosomal recessive neurodegenerative spinal muscle atrophy (SMA). A potential treatment strategy for SMA is to upregulate the amount of SMN protein originating from the highly homologous SMN2 gene, compensating in part for the absence of the functional SMN1 gene. We have previously shown that in vitro activation of the p38 pathway stabilizes and increases SMN mRNA levels leading to increased SMN protein levels. In this report, we explore the impact of the p38 activating, FDA-approved, blood brain barrier permeating compound celecoxib on SMN levels in vitro and in a mouse model of SMA. We demonstrate a significant induction of SMN protein levels in human and mouse neuronal cells upon treatment with celecoxib. We show that activation of the p38 pathway by low doses celecoxib increases SMN protein in a HuR protein-dependent manner. Furthermore, celecoxib treatment induces SMN expression in brain and spinal cord samples of wild-type mice in vivo. Critically, celecoxib treatment increased SMN levels, improved motor function and enhanced survival in a severe SMA mouse model. Our results identify low dose celecoxib as a potential new member of the SMA therapeutic armamentarium.
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Encéfalo/efectos de los fármacos , Pirazoles/farmacología , Médula Espinal/efectos de los fármacos , Atrofias Musculares Espinales de la Infancia/metabolismo , Sulfonamidas/farmacología , Proteína 1 para la Supervivencia de la Neurona Motora/metabolismo , Proteína 2 para la Supervivencia de la Neurona Motora/metabolismo , Adolescente , Animales , Encéfalo/metabolismo , Celecoxib , Células Cultivadas , Niño , Preescolar , Modelos Animales de Enfermedad , Proteínas ELAV/metabolismo , Regulación de la Expresión Génica , Humanos , Lactante , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Sistema de Señalización de MAP Quinasas/genética , Ratones , Neuronas Motoras/efectos de los fármacos , Neuronas Motoras/metabolismo , Pirazoles/uso terapéutico , Médula Espinal/metabolismo , Atrofias Musculares Espinales de la Infancia/tratamiento farmacológico , Atrofias Musculares Espinales de la Infancia/genética , Atrofias Musculares Espinales de la Infancia/fisiopatología , Sulfonamidas/uso terapéutico , Proteína 1 para la Supervivencia de la Neurona Motora/genética , Proteína 2 para la Supervivencia de la Neurona Motora/genéticaRESUMEN
The Inhibitor of Apoptosis (IAP) family possesses the ability to inhibit programmed cell death through different mechanisms; additionally, some of its members have emerged as important regulators of the immune response. Both direct and indirect activity on caspases or the modulation of survival pathways, such as nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), have been implicated in mediating its effects. As a result, abnormal expression of inhibitor apoptosis proteins (IAPs) can lead to dysregulated apoptosis promoting the development of different pathologies. In several cancer types IAPs are overexpressed, while their natural antagonist, the second mitochondrial-derived activator of caspases (Smac), appears to be downregulated, potentially contributing to the acquisition of resistance to traditional therapy. Recently developed Smac mimetics counteract IAP activity and show promise in the re-sensitization to apoptosis in cancer cells. Given the modest impact of Smac mimetics when used as a monotherapy, pairing of these compounds with other treatment modalities is increasingly being explored. Modulation of molecules such as tumor necrosis factor-α (TNF-α) present in the tumor microenvironment have been suggested to contribute to putative therapeutic efficacy of IAP inhibition, although published results do not show this consistently underlining the complex interaction between IAPs and cancer.
RESUMEN
Signaling lymphocytic activation molecule family 8 (SLAMF8) is involved in the negative modulation of NADPH oxidase activation. However, the impact of SLAMF8 downregulation on macrophage functionality and the microbicide mechanism remains elusive. To study this in depth, we first analyzed NADPH oxidase activation pathways in wild-type and SLAMF8-deficient macrophages upon different stimulus. Herein, we describe increased phosphorylation of the Erk1/2 and p38 MAP kinases, as well as increased phosphorylation of NADPH oxidase subunits in SLAMF8-deficient macrophages. Furthermore, using specific inhibitors, we observed that specific PI3K inhibition decreased the differences observed between wild-type and SLAMF8-deficient macrophages, stimulated with either PMA, LPS, or Salmonella typhimurium infection. Consequently, SLAMF8-deficient macrophages also showed increased recruitment of small GTPases such as Rab5 and Rab7, and the p47phox subunit to cytoplasmic Salmonella, suggesting an impairment of Salmonella-containing vacuole (SCV) progression in SLAMF8-deficient macrophages. Enhanced iNOS activation, NO production, and IL-6 expression were also observed in the absence of SLAMF8 upon Salmonella infection, either in vivo or in vitro, while overexpression of SLAMF8 in RAW264.7 macrophages showed the opposite phenotype. In addition, SLAMF8-deficient macrophages showed increased activation of Src kinases and reduced SHP-1 phosphate levels upon IFNγ and Salmonella stimuli in comparison to wild-type macrophages. In agreement with in vitro results, Salmonella clearance was augmented in SLAMF8-deficient mice compared to that in wild-type mice. Therefore, in conclusion, SLAMF8 intervention upon bacterial infection downregulates mouse macrophage activation, and confirmed that SLAMF8 receptor could be a potential therapeutic target for the treatment of severe or unresolved inflammatory conditions.
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Antiinfecciosos , Proteínas de la Membrana/metabolismo , Infecciones por Salmonella , Animales , Antiinfecciosos/metabolismo , Macrófagos/metabolismo , Ratones , NADPH Oxidasas/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Infecciones por Salmonella/metabolismo , Familia de Moléculas Señalizadoras de la Activación Linfocitaria/genéticaRESUMEN
The neuronal apoptosis inhibitory protein (NAIP) is a constituent of the NLRC4 inflammasome, which plays a key role in innate immunity, and an antiapoptotic protein. Recently, we reported the previously undescribed role of NAIP in cell division. The liver is one of the body's most actively regenerative organs. Given the novel mitotic role of NAIP, we examined its expression in hepatic mass restoration. The major liver lobe of Wistar rats was removed, and samples from both newly formed liver tissue, assessed by positive Ki67 immunostaining, and the remnant, intact liver lobes from hepatectomized rats were taken 3 and 7 days after surgery. Naip5 and Naip6 mRNA levels were significantly higher in regenerating hepatic tissue than in intact liver lobe tissue, and this increase was also observed at the protein level. Naip5 and Naip6 mRNA in situ hybridization showed that this increase occurred in the hepatic parenchyma. The histology of the regenerated liver tissue was normal, with the exception of a noticeable deficiency of hepatic lobule central veins. The results of this study suggest the involvement of NAIP in liver mass restoration following partial hepatectomy.
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Hígado/anatomía & histología , Hígado/metabolismo , Proteína Inhibidora de la Apoptosis Neuronal/metabolismo , Animales , División Celular , Línea Celular , Regulación de la Expresión Génica , Hepatocitos/citología , Hepatocitos/metabolismo , Humanos , Regeneración Hepática/genética , Masculino , Modelos Animales , Proteína Inhibidora de la Apoptosis Neuronal/genética , Tamaño de los Órganos , ARN Mensajero/genética , ARN Mensajero/metabolismo , Ratas WistarRESUMEN
Non-alcoholic fatty liver disease (NAFLD) has reached pandemic proportions worldwide. We have previously reported that the probiotic strains Bifidobacterium breve CNCM I-4035, Lactobacillus paracasei CNCM I-4034 and Lactobacillus rhamnosus CNCM I-4036 exert anti-inflammatory effects in the intestine of Zucker-Lepr fa/fa rats. In this work, we focused on their hepatic effects. M1 macrophages are related to inflammation and NAFLD pathogenesis, whereas M2 macrophages release anti-inflammatory mediators. We evaluated the effects of these 3 strains on macrophage polarization, inflammation and liver damage of Zucker-Lepr fa/fa rats. The animals received either a placebo or 1010 CFU of probiotics orally for 30 days. Nos2 and Cd86 mRNA levels were determined as markers of M1 macrophages, and Cd163 and Arg1 as M2 markers, respectively, by qRT-PCR. Liver damage was determined by lipid peroxidation, leukocyte infiltration and myeloperoxidase activity. We evaluated a panoply of circulating chemokines, the hepatic ratio P-Akt/Akt, NF-kB and P-NF-kB protein levels. All 3 probiotic strains modulated macrophage polarization in liver and circulating levels of inflammation-related mediators. L. paracasei CNCM I-4034 increased the ratio P-Akt/Akt and NF-kB protein levels. B. breve CNCM I-4035, L. paracasei CNCM I-4034 and L. rhamnosus CNCM I-4036 decreased both pro-inflammatory macrophage gene expression and leukocyte infiltration in the liver.
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Bifidobacterium breve , Regulación de la Expresión Génica , Lacticaseibacillus rhamnosus , Hepatopatías/metabolismo , Hígado/metabolismo , Macrófagos/metabolismo , Probióticos/farmacología , Animales , Biomarcadores/metabolismo , Hígado/patología , Hepatopatías/patología , Macrófagos/patología , Masculino , Ratas , Ratas ZuckerRESUMEN
Sweeteners that are a hundred thousand times sweeter than sucrose are being consumed as sugar substitutes. The effects of sweeteners on gut microbiota composition have not been completely elucidated yet, and numerous gaps related to the effects of nonnutritive sweeteners (NNS) on health still remain. The NNS aspartame and acesulfame-K do not interact with the colonic microbiota, and, as a result, potentially expected shifts in the gut microbiota are relatively limited, although acesulfame-K intake increases Firmicutes and depletes Akkermansia muciniphila populations. On the other hand, saccharin and sucralose provoke changes in the gut microbiota populations, while no health effects, either positive or negative, have been described; hence, further studies are needed to clarify these observations. Steviol glycosides might directly interact with the intestinal microbiota and need bacteria for their metabolization, thus they could potentially alter the bacterial population. Finally, the effects of polyols, which are sugar alcohols that can reach the colonic microbiota, are not completely understood; polyols have some prebiotics properties, with laxative effects, especially in patients with inflammatory bowel syndrome. In this review, we aimed to update the current evidence about sweeteners' effects on and their plausible biological interactions with the gut microbiota.
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Microbioma Gastrointestinal/efectos de los fármacos , Edulcorantes no Nutritivos/farmacología , Aspartame/farmacología , Diterpenos de Tipo Kaurano/farmacología , Glucósidos/farmacología , Humanos , Polímeros/farmacología , Sacarina/farmacología , Sacarosa/análogos & derivados , Sacarosa/farmacología , Tiazinas/farmacologíaRESUMEN
The importance of gut microbiota in health and disease is being highlighted by numerous research groups worldwide. Atherosclerosis, the leading cause of heart disease and stroke, is responsible for about 50% of all cardiovascular deaths. Recently, gut dysbiosis has been identified as a remarkable factor to be considered in the pathogenesis of cardiovascular diseases (CVDs). In this review, we briefly discuss how external factors such as dietary and physical activity habits influence host-microbiota and atherogenesis, the potential mechanisms of the influence of gut microbiota in host blood pressure and the alterations in the prevalence of those bacterial genera affecting vascular tone and the development of hypertension. We will also be examining the microbiota as a therapeutic target in the prevention of CVDs and the beneficial mechanisms of probiotic administration related to cardiovascular risks. All these new insights might lead to novel analysis and CVD therapeutics based on the microbiota.
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Aterosclerosis/microbiología , Aterosclerosis/patología , Microbioma Gastrointestinal , Animales , Aterosclerosis/prevención & control , Aterosclerosis/terapia , Trasplante de Microbiota Fecal , Humanos , Terapia Molecular Dirigida , Medicina de Precisión , Probióticos/uso terapéuticoRESUMEN
Neutrophils are key cells of the immune system and have a decisive role in fighting foreign pathogens in infectious diseases. Neutrophil extracellular traps (NETs) consist of a mesh of DNA enclosing antimicrobial peptides and histones that are released into extracellular space following neutrophil response to a wide range of stimuli, such as pathogens, host-derived mediators and drugs. Neutrophils can remain functional after NET formation and are important for periodontal homeostasis. Periodontitis is an inflammatory multifactorial disease caused by a dysbiosis state between the gingival microbiome and the immune response of the host. The pathogenesis of periodontitis includes an immune-inflammatory component in which impaired NET formation and/or elimination can be involved, contributing to an exacerbated inflammatory reaction and to the destruction of gingival tissue. In this review, we summarize the current knowledge about the role of NETs in the pathogenesis of periodontitis.
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Trampas Extracelulares/metabolismo , Neutrófilos/metabolismo , Periodontitis/patología , Especies Reactivas de Oxígeno/metabolismo , ADN/genética , Trampas Extracelulares/inmunología , Humanos , Inmunidad Innata/inmunología , Inflamación/inmunología , Neutrófilos/inmunología , Periodontitis/inmunologíaRESUMEN
The aims of this cross-sectional study were (i) to determine the association of educational level attained with cognitive impairment and (ii) to investigate the mediating effect of different self-report physical activity (PA) patterns in a large sample of older Chileans. A sample of 1571 older adults from the National Chilean Survey (2016-2017) was included. The educational level attained, PA levels, mode of commuting, sedentary time, and leisure-time PA were self-reported through validated questionnaires. Cognitive impairment was determined by Mini-Mental State Examination (modified version). Association between educational level attained and cognitive impairment was examined using logistic regression models. Counterfactual mediation models were used to test the mediating effect of self-reported PA patterns. A lower educational level was consistently associated with higher odds of cognitive impairment (OR range 2.846 to 2.266, all p < 0.001), while leisure-time PA was the only PA pattern that partially mediated this association (proportion mediated 8.0%). In conclusion, leisure-time PA was the solely PA pattern that partially mediated the association between the educational level and cognitive impairment. The rest self-reported PA patterns did not modify this association.
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Disfunción Cognitiva , Conducta Sedentaria , Anciano , Chile , Estudios Transversales , Ejercicio Físico , Femenino , Humanos , Masculino , Autoinforme , Encuestas y CuestionariosRESUMEN
Specific microbial profiles and changes in intestinal microbiota have been widely demonstrated to be associated with the pathogenesis of a number of extra-intestinal (obesity and metabolic syndrome) and intestinal (inflammatory bowel disease) diseases as well as other metabolic disorders, such as non-alcoholic fatty liver disease and type 2 diabetes. Thus, maintaining a healthy gut ecosystem could aid in avoiding the early onset and development of these diseases. Furthermore, it is mandatory to evaluate the alterations in the microbiota associated with pathophysiological conditions and how to counteract them to restore intestinal homeostasis. This review highlights and critically discusses recent literature focused on identifying changes in and developing gut microbiota-targeted interventions (probiotics, prebiotics, diet, and fecal microbiota transplantation, among others) for the above-mentioned pathologies. We also discuss future directions and promising approaches to counteract unhealthy alterations in the gut microbiota. Altogether, we conclude that research in this field is currently in its infancy, which may be due to the large number of factors that can elicit such alterations, the variety of related pathologies, and the heterogeneity of the population involved. Further research on the effects of probiotics, prebiotics, or fecal transplantations on the composition of the human gut microbiome is necessary.
RESUMEN
Monocytes and macrophages constitute the first line of defense of the immune system against external pathogens. Macrophages have a highly plastic phenotype depending on environmental conditions; the extremes of this phenotypic spectrum are a pro-inflammatory defensive role (M1 phenotype) and an anti-inflammatory tissue-repair one (M2 phenotype). The Inhibitor of Apoptosis (IAP) proteins have important roles in the regulation of several cellular processes, including innate and adaptive immunity. In this study we have analyzed the differential expression of the IAPs, NAIP, cIAP1 and cIAP2, during macrophage differentiation and polarization into M1 or M2. In polarized THP-1 cells and primary human macrophages, NAIP is abundantly expressed in M2 macrophages, while cIAP1 and cIAP2 show an inverse pattern of expression in polarized macrophages, with elevated expression levels of cIAP1 in M2 and cIAP2 preferentially expressed in M1. Interestingly, treatment with the IAP antagonist SMC-LCL161, induced the upregulation of NAIP in M2, the downregulation of cIAP1 in M1 and M2 and an induction of cIAP2 in M1 macrophages.
Asunto(s)
Proteína 3 que Contiene Repeticiones IAP de Baculovirus/metabolismo , Diferenciación Celular/fisiología , Proteínas Inhibidoras de la Apoptosis/metabolismo , Macrófagos/metabolismo , Proteína Inhibidora de la Apoptosis Neuronal/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Proteínas Reguladoras de la Apoptosis , Western Blotting , Diferenciación Celular/efectos de los fármacos , Células Cultivadas , Citometría de Flujo , Expresión Génica , Perfilación de la Expresión Génica , Humanos , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Macrófagos/citología , Macrófagos/efectos de los fármacos , Proteínas Mitocondriales/metabolismo , Monocitos/citología , Monocitos/metabolismo , ARN Mensajero/metabolismoRESUMEN
The neuronal apoptosis inhibitory protein (NAIP) is a constituent of the inflammasome and a key component of the innate immune system. Here we use immunofluorescence to position NAIP within the cytokinetic apparatus, contiguous to chromosomal passenger complex (CPC), Centralspindlin, PRC1 and KIF4A. During metaphase, NAIP accumulates in the mitotic spindle poles and is shown in spindle microtubules; in anaphase NAIP is detected in the middle of the central spindle. At the end of cytokinesis, NAIP is localized in the outlying region of the stem body, the center of the intercellular bridge formed between daughter cells prior to cellular abscission. We also describe the sustained presence of NAIP mRNA and protein throughout the cell cycle with a significant increase observed in the G2/M phase. Consistent with a role for NAIP in cytokinesis, NAIP overexpression in HeLa cells promotes the acquisition of a multinuclear phenotype. Conversely, NAIP siRNA gene silencing results in an apoptotic lethal phenotype. Our confocal and super resolution stimulated-emission-depletion (STED) examination of mammalian cell cytokinesis demonstrate a potential new role for NAIP in addition to anti-apoptotic and innate immunology functions.
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Citocinesis , Proteína Inhibidora de la Apoptosis Neuronal/genética , Proteína Inhibidora de la Apoptosis Neuronal/metabolismo , Huso Acromático/metabolismo , Proteínas de Ciclo Celular/metabolismo , Supervivencia Celular , Células HeLa , Humanos , Cinesinas/metabolismo , Microscopía Confocal , Mitosis , Fenotipo , Polos del Huso/metabolismo , Regulación hacia ArribaRESUMEN
We investigated whether the administration of Lactobacillus paracasei CNCM I-4034, Bifidobacterium breve CNCM I-4035 and Lactobacillus rhamnosus CNCM I-4036 modulate the expression of genes in the intestinal mucosa of obese Zucker rats. Forty-eight Zucker-Leprfa/fa and 16 Zucker lean Lepr+/fa rats were used. Eight Zucker lean Lepr+/fa and 8 Zucker-Leprfa/fa rats were euthanized as a reference. The remaining 40 Zucker-Leprfa/fa rats were then assigned to receive 1010 colony forming units (CFU) of one of the three probiotic strains, a mixture of L. paracasei CNCM I-4034 and B. breve CNCM I-4035, or a placebo by oral administration for 30 days. An additional group of 8 Zucker lean Lepr+/fa rats received the placebo for 30 days. Over 27,000 rat genes were studied using a DNA array. Four animals per group were used. Total RNA was extracted from intestinal mucosa and cDNA was synthesized, fragmented and labeled. Labeled cDNA was hybridized using GeneChip kits, and the latter were scanned. Intensity values of each probe were processed and normalized to obtain an individual value for each set of probes.
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Mucosa Intestinal , Obesidad/genética , Animales , Perfilación de la Expresión Génica , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiología , Obesidad/patología , Probióticos/administración & dosificación , Ratas , Ratas ZuckerRESUMEN
We have previously reported that administration of Lactobacillus paracasei CNCM I-4034, Bifidobacterium breve CNCM I-4035 and Lactobacillus rhamnosus CNCM I-4036 to obese Zucker-Lepr fa/fa rats attenuates liver steatosis and exerts anti-inflammatory effects. The goal of the present work was to investigate the modulation of gene expression in intestinal mucosa samples of obese Zucker-Lepr fa/fa rats fed the probiotic strains using a DNA microarray and postgenomic techniques. We also measured secretory IgA content in the gut and lipopolysaccharide (LPS)-binding protein (LBP) in serum. Expression of three genes (Adamdec1, Ednrb and Ptgs1/Cox1) was up-regulated in the intestinal mucosa of the obese rats compared with that in the rats when they were still lean. Probiotic administration down-regulated expression of Adamdec1 and Ednrb at the mRNA and protein levels and that of Ptgs1/Cox1 at the mRNA level, and this effect was in part mediated by a decrease in both macrophage and dendritic cell populations. Probiotic treatment also increased secretory IgA content and diminished the LBP concentration. Based on results reported in this work and else where, we propose a possible mechanism of action for these bacterial strains.
Asunto(s)
Proteínas ADAM/genética , Ciclooxigenasa 1/genética , Enteritis/etiología , Microbioma Gastrointestinal , Mucosa Intestinal/metabolismo , Proteínas de la Membrana/genética , Probióticos , Receptor de Endotelina B/genética , Animales , Células Dendríticas/inmunología , Células Dendríticas/metabolismo , Expresión Génica , Mucosa Intestinal/patología , Macrófagos/inmunología , Macrófagos/metabolismo , Obesidad , Fenotipo , Ratas , Ratas ZuckerRESUMEN
We have previously described the safety and immunomodulatory effects of Lactobacillus paracasei CNCM I-4034, Bifidobacterium breve CNCM I-4035 and Lactobacillus rhamnosus CNCM I-4036 in healthy volunteers. The scope of this work was to evaluate the effects of these probiotic strains on the hepatic steatosis of obese rats. We used the Zucker rat as a genetic model of obesity. Zucker-Lepr(fa/fa) rats received one of three probiotic strains, a mixture of L. paracasei CNCM I-4034 and B. breve CNCM I-4035, or a placebo for 30 days. An additional group of Zucker-lean+/fa rats received a placebo for 30 days. No alterations in intestinal histology, in the epithelial, lamina propria, muscular layers of the ileal or colonic mucosa, or the submucosae, were observed in any of the experimental groups. Triacylglycerol content decreased in the liver of Zucker-Lepr(fa/fa) rats that were fed L. rhamnosus, B. breve, or the mixture of B. breve and L. paracasei. Likewise, the area corresponding to neutral lipids was significantly smaller in the liver of all four groups of Zucker-Lepr(fa/fa) rats that received probiotics than in rats fed the placebo. Zucker-Lepr(fa/fa) rats exhibited significantly greater serum LPS levels than Zucker-lean+/fa rats upon administration of placebo for 30 days. In contrast, all four groups of obese Zucker-Lepr(fa/fa) rats that received LAB strains exhibited serum LPS concentrations similar to those of Zucker-lean+/fa rats. Serum TNF-α levels decreased in the Zucker-Lepr(fa/fa) rats that received B. breve, L. rhamnosus, or the mixture, whereas L. paracasei feeding decreased IL-6 levels in the serum of Zucker-Lepr(fa/fa) rats. In conclusion, the probiotic strains reduced hepatic steatosis in part by lowering serum LPS, and had an anti-inflammatory effect in obese Zucker rats.