Mucosal expression of defensin-5, soluble phospholipase A2 and lysozyme in the intestine in a rat model of acute liver failure and its relationship to intestinal bacterial translocation / Expresión de defensina-5, fosfolipasa A2 soluble y lisozima en la mucosa intestinal en un modelo de rata con insuficiencia hepática aguda y su relación con la traslocación bacteriana intestinal

INTRODUCTION: To study the expression of defensin-5 (RD-5), soluble phospholipase A2 (sPLA2) and lysozyme in the intestine in a rat model of acute liver failure and its relationship with intestinal bacterial translocation (BT). PATIENTS AND METHODS: Sprague-Dawley (SD) rats were divided into two groups. The experimental group was divided into five subgroups according to the lapsing time after the model was established, which were designated accordingly as 8 h, 16 h, 24 h, 48 h, and 72 h groups. Acute liver failure (ALF) model was induced by intraperitoneal injection of 10% d-galactosamine. The homogenates of mesenteric lymph nodes (MLNs), liver and spleen from each group were cultured in agar to determine the bacterial outgrowth. The mRNA expression of RD-5, sPLA2, lysozyme and the protein expression of sPLA2, lysozyme were determined. RESULTS: No bacteria grew in the organ cultures from the control group while experimental groups had positive cultures. Expression of the RD-5 and sPLA2 mRNA in the experimental groups gradually increased at early time points and peaked 16 h after induction of ALF, then progressively decreased. The mRNA expression of lysozyme in the experimental group peaked at 8 h after ALF induction, then progressively decreased. Similar results were obtained with Western blot and immunohistochemical staining. DISCUSSION: The immune barrier function of the ileal mucosa in the rat model of acute liver failure was compromised as demonstrated by the decreased expression of RD-5, sPLA2 and lysozyme in Paneth cells along with increased intestinal bacterial translocation

INTRODUCCIÓN: Estudiar la expresión de defensina-5 (RD-5), fosfolipasa A2 soluble (sPLA2) y lisozima en el intestino de un modelo de rata con insuficiencia hepática aguda y su relación con la traslocación bacteriana (TB) intestinal. PACIENTES Y MÉTODOS: Se dividieron ratas Sprague-Dawley® (SD) en 2 grupos. El grupo experimental se dividió en 5 subgrupos según el tiempo transcurrido desde que se estableció el modelo, y se designaron en consecuencia como grupos de 8, 16, 24, 48 y 72 h. El modelo de insuficiencia hepática aguda (IHA) se indujo mediante inyección intraperitoneal de D-galactosamina al 10%. Se cultivaron homogeneizados de ganglios linfáticos mesentéricos (GLM), hígado y bazo de cada grupo en agar para determinar la proliferación bacteriana. Se determinaron la expresión de ARNm de RD-5, sPLA2 y lisozima, y la expresión de proteínas de sPLA2 y lisozima. RESULTADOS: En los cultivos de órganos del grupo de control no creció ninguna bacteria, mientras que los grupos experimentales presentaron cultivos positivos. La expresión del ARNm de RD-5 y sPLA2 en los grupos experimentales aumentó gradualmente en los primeros momentos y alcanzó el máximo 16 h después de la inducción de la IHA, para después disminuir de forma progresiva. La expresión de lisozima en el grupo experimental alcanzó el valor máximo 8 h después de la inducción de la IHA y después disminuyó progresivamente. Se obtuvieron resultados similares con la inmunoelectrotransferencia y la tinción inmunohistoquímica. DISCUSIÓN: La función de barrera inmunológica de la mucosa ileal en el modelo de rata de insuficiencia hepática aguda se vio afectada, como lo demuestra la disminución de la expresión de RD-5, sPLA2 y lisozima en las células de Paneth junto con el aumento de la translocación bacteriana intestinal

Beyond anti-microbial properties: The role of cathelicidin in allergic rhinitis

BACKGROUND: Cathelicidin, an anti-microbial peptide, is a component of the innate immune system. Cathelicidin has anti-microbial, anti-inflammatory and immunoregulatory functions. Knowledge about the role of the innate immune system in the pathogenesis of allergic diseases has expanded in recent years. We measured levels of the LL-37 peptide in the nasal fluids of children with allergic rhinitis (AR) and investigated the possible role of this peptide in the pathogenesis of AR. METHODS: The study population included 46 children who were newly diagnosed with AR and not taking any medication. Thirty-three healthy control subjects were also enrolled. Nasal secretions were collected from the study and control groups using a polyurethane sponge nasal secretion collector, and nasal fluid LL-37 levels were determined using the ELISA method. Results; The levels of LL-37 in the nasal fluid of the AR patients were lower than those of the control group (median of 2.3ng/ml [minimum-maximum, 2.1-3.2] vs. 2.6 ng/ml [2.1-5.4], respectively; p < 0.001), and they were significantly reduced in patients with moderate/severe AR compared with those of patients with mild AR (2.2 ng/ml [2.1-2.4] vs. 2.5 ng/ml [2.1-3.1], respectively; p < 0.001). CONCLUSION: Our results show that children with AR have reduced nasal fluid LL-37 levels compared with healthy controls. Additionally, children with moderate/severe AR have decreased nasal fluid LL-37 levels compared with children with mild AR. These findings highlight the role of cathelicidin in the pathogenesis of AR

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Antibióticos humanos modulados por calcitriol: nuevos aspectos fisiopatológicos de la hipovitaminosis D / Calcitriol-modulated human antibiotics: New pathophysiological aspects of vitamin D

El calcitriol ha sido considerado durante años exclusivamente como una hormona reguladora del metabolismo fosfocálcico, pero últimamente se ha demostrado que numerosas células implicadas en la inmunidad innata (epitelios de barrera, monocitos/macrófagos, etc.) son capaces de reconocer determinadas moléculas repetitivas características de diversos gérmenes patógenos mediante receptores de membrana o intranucleares. La activación de estos receptores induce la síntesis de la 1α-hidroxilasa, con lo que dichas células son capaces de sintetizar calcitriol a partir de la 25 hidroxivitamina D circulante. El calcitriol, a través del receptor la vitamina D, modula la expresión de determinados péptidos antimicrobianos, como la catelicidina, la β2-defensina o la hepcidina. Estos péptidos representan un mecanismo versátil de la lucha antibacteriana innata y su producción se ve alterada en la hipovitaminosis D. Se realiza un análisis de la literatura sobre sus mecanismos de secreción, las concentraciones en diversos líquidos orgánicos, y los mecanismos de acción y su relación con la vitamina D (AU)

Traditionally, calcitriol has been considered a calcium and phosphate regulating hormone, but has recently been shown to play a pivotal role in innate immunity. Many barrier and immune cells have membrane and intracellular receptors that recognize different microbial antigens. Activation of these receptors induces synthesis of 1α-hydroxylase, which acts on 25 hydroxyvitamin D to generate intracellular calcitriol. Calcitriol activates its receptor and enhances the synthesis of important human antibiotics like cathelicidin and β2-defensin while inhibiting hepcidin. These pluripotent peptides have an important role in innate immunity, and their regulation is abnormal in hypovitaminosis D. The literature on their secretion mechanisms, levels in different organic fluids, mechanism of action, and relationship with vitamin D is reviewed here (AU)

Flora intestinal, probióticos, prebióticos, simbióticos y alimentos novedosos / Intestinal flora, probiotics, prebiotics, synbiotics and novel foods

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