El consumo de un extracto de calafate (Berberis microphylla) modifica marcadores de respuesta inmune en ratones delgados y obesos

RESUMEN La obesidad ha sido identificada como factor de riesgo de severidad de infecciones respiratorias. Apoyar la respuesta inmune en sujetos obesos es de interés. El presente trabajo evaluó el efecto del consumo de un extracto de calafate sobre marcadores de respuesta inmune en ratones delgados y obesos. Ratones C57BL/6J machos fueron expuestos por 82 días a dieta estándar (DE) y alta en grasas (DAG). A un subgrupo de ambos grupos, se les administró 50 y 100 mg [polifenoles totales]/kg peso de animal/día, de extracto, en las últimas dos semanas. Se evaluó expresión génica y secreción de marcadores de respuesta inmune, en tejido pulmonar y plasma. Se observó un efecto del tratamiento con extracto en la expresión de IFN-ϓ. Se observaron efectos inducidos por la DAG y el tratamiento con extracto de manera independiente, en la expresión de IL-12. Se observó un efecto global de la DAG sobre IFN-ϓ plasmático, específicamente una disminución en animales alimentados con DAG. Se observó una interacción entre la dieta y el tratamiento con extracto sobre IL-12 plasmática. El tratamiento utilizado modula marcadores que activan la respuesta inmune ante infecciones respiratorias principalmente de origen viral, en animales delgados y obesos.

ABSTRACT Obesity has been identified as a risk factor for severity of respiratory infections. Thus, the support of the immune response in obese subjects is of interest. The present work evaluated the effect of the consumption of a calafate extract on markers of the immune response in lean and obese mice. Male C57BL/6J mice were exposed for 82 days to a standard or a high-fat diet (HFD). A subgroup of both groups was given 50 and 100 mg [total polyphenols]/kg body weight/day of extract in the last two weeks. Gene expression and secretion of immune response markers were evaluated in lung tissue and plasma. An effect of extract treatment on IFN-ϓ expression was observed. Effects induced by the HFD and treatment with extract were observed independent of the expression of IL-12. An overall effect of the HF diet on plasma IFN-ϓ was observed, specifically a decrease in animals fed the HFD. An interaction between diet and extract treatment was observed over plasma IL-12. The treatment used modulates markers that activate the immune response to respiratory infections, mainly of viral origin, in lean and obese animals.

Caracterización de extractos de piel y hojas de Persea americana Mill. y analisis in vitro de sus potenciales propiedades anti-inflamatorias / Characterization of Persea americana Mill. peels and leaves extracts and analysis of its potential in vitro anti-inflammatory properties

Existe una tendencia mundial de incremento en prevalencia de enfermedades no transmisibles, que se caracterizan por un estado pro-inflamatorio crónico. Por lo tanto, es importante estudiar la relación entre alimentos y salud. La palta (Persea americana), sobresale en la industria por su valor nutricional. El procesamiento de la palta genera gran cantidad de subproductos, que contienen bioactivos con propiedades beneficiosas, como polifenoles. El objetivo del presente trabajo fue caracterizar cuatro extractos de palto (acuoso e hidroalcohólico; de hoja y de cáscara) y analizar sus posibles propiedades anti-inflamatorias in vitro. Fueron determinados polifenoles totales (con el método de Folin­Ciocalteau) y capacidad antioxidante (por FRAP y DPPH) de los extractos. Las propiedades anti-inflamatorias de los extractos fueron determinadas por la liberación de NO y de TNF-, y por la expresión génica de TNF-. Los resultados indican que los extractos hidroalcohólicos presentan más polifenoles (p<0,001) y capacidad antioxidante (p<0,001, por FRAP) que los acuosos. Mas aún, observamos que los extractos hidroalcohólicos de hojas presentaron mayores efectos anti-inflamatorios in vitro, especialmente el hidroalcohólico de hoja en liberación de NO (p<0,001, frente a tratamiento con LPS), acuosos e hidroalcohólicos en liberación de TNF- (p<0,05), y solo los hidroalcohólicos en la expresión de TNF- (p<0,01). En conclusión, los extractos hidroalcohólicos de palto, y especialmente el de hoja, presentan propiedades anti-inflamatorias in vitro que pueden ser consideradas para aplicaciones en mejoría de salud humana.

There is a worldwide trend of increasing prevalence of non-communicable diseases characterized by a chronic inflammatory state. Therefore, it is important to study the relationship between food and health. Avocado (Persea americana) stands out in food industry for its nutritional value. Industrials process of avocado generates a large number of by-products, which contain phytochemical compounds with antioxidant properties, such as polyphenols. The objective of the present research was to characterize four aqueous and hydroalcoholic extracts from avocado leaves and peels and analyze it possible anti-inflammatory properties in vitro. Total polyphenol content (with the Folin-Ciocalteau method) and antioxidant capacity (by FRAP and DPPH) were determined. Extracts inflammatory features were measured by NO and TNF- release, and by TNF- gene expression. Our results indicated that hydroalcoholic extracts present higher total polyphenol content (p<0.001) and antioxidant capacity (p<0.001, by FRAP) than the aqueous ones. Furthermore, we report that hydroalcoholic leaves extract presented greater in vitro anti-inflammatory effect, especially the leave hydroalcoholic regarding NO release (p<0.001, against LPS treatment), aqueous and hydroalcoholics regarding TNF- release (p<0.05), and only the hydroalcoholic in the TNF- gene expression (p<0.01). In conclusion, the avocado hydroalcoholic extracts, and especially from leaves, present in vitro anti-inflammatory features that might be considered for human health improvement applications.

Obesidad parental y modificaciones epigenéticas en la descendencia / Parental obesity and epigenetic modifications in offspring

RESUMEN La obesidad es una enfermedad multifactorial definida como acumulación patológica de grasa. Su prevalencia ha aumentado enormemente en el mundo. Chile presenta una de las mayores prevalencias de obesidad de la OCDE. Su casuística simplificada comprende una diferencia sostenida entre gasto e ingesta de energía, manteniendo un delta positivo traducido en mayor acumulación de grasa. No obstante, la etiología completa de esta enfermedad comprende también factores psicológicos, genéticos, ambientales, etc. El ambiente juega un papel clave en la predisposición al consumo de alimentos, a la realización de ejercicio físico, incluso afectando la susceptibilidad genómica, exacerbando o disminuyendo la carga genética. Esta modificación de susceptibilidad genética por el ambiente se conoce como epigenética, que se refiere a una serie de modificaciones por "sobre" la genética que son altamente modificables por factores ambientales. Se ha descrito que algunas de estas modificaciones pueden heredarse de una generación a otra, lo que otorga otro nivel de complejidad al estudio de nuevas terapias complementarias para frenar la tendencia al sobrepeso. En la presente revisión se describe cuales son las modificaciones epigenéticas más frecuentes encontradas, su relación con obesidad y dieta, y finalmente como se relaciona con la transmisión transgeneracional de esta patología.

ABSTRACT Obesity is a multifactorial disease defined by a pathological accumulation of body fat. Its prevalence has increased greatly across the world. Chile has one of the highest prevalence of obesity among OCDE countries. It is caused by a sustained difference between energy expenditure and intake, keeping a positive delta, which drives fat accumulation. However, its etiology is comprised several factors: psychological, genetics, environmental, etc. The environment plays a key role in the predisposition towards food consumption, the adoption of exercise, and genetic susceptibility, increasing or decreasing the genetic load towards obesity. This modification of susceptibility is known as epigenetics, which refers to modifications "over" genetics, which are highly modifiable by environmental factors. Some of these modifications can be inherited from one generation to another, granting a higher complexity level regarding designing novel complementary therapies against obesity. Thus, the present review described which epigenetic modifications are related to obesity and different dietary patterns, and finally how epigenetic modifications can be related to transgenerational transmission of obesity.

Efectividad de ejercicio físico intervalado de alta intensidad en las mejoras del fitness cardiovascular, muscular y composición corporal en adolescentes: una revisión / High intensity interval training in teenagers

This review analyzes the effects of high intensity interval training (HIIT) on muscle and cardiovascular fitness and body composition in teenagers. A search was carried out in international databases, finding 145 papers and selecting five for analysis. In all the reviewed manuscripts, peak oxygen uptake improved after HIIT. In the three manuscripts that measured muscle strength, it also increased. We conclude that HIIT improves muscle strength and cardiovascular fitness in school age children. A 12 weeks protocol with three 12-minute sessions per week would be ideal.

Cinética de muerte de linfocitos en diabetes mellitus tipo 1 y su posible asociación con miR-146a y miR-155 / Kinetics of cell death in type 1 diabetes mellitus and their possible association with miR-146a and miR-155

Aim: Analyze mi-146a and miR-155 expression and its correlation with the apoptosis of lymphocytes T in T1D and control patient. Patients and Methodology: 17 T1D patients (5 children between 8-14 yr and 12 adults between 19-29 yr). Activated and not activated peripheral mononuclear cells were studied were studied. Cellular activation with anti-CD3 and primary culture with interleukyne-2 by 5 days. Apoptosis assays through flow cytometry. miRNA through Taqman probes. Statistical analysis through Kruskal-Wallis and post-hoc Dunn's test. Results: Composition of virgin and memory T CD4 cells showed significant differences for stimulus response in control group (p = 0,0004). Increased memory cells count in control group activated by 7 days than basal (p = 0,0047). For early apoptosis differences were observed in days 3 and 7 with and without activation (p = 0,001). AICD apoptosis showed increases in control group after re-stimulation through TCR (p= 0,03). miR-146a expression was lower in recent-onset T1D children vs recent-onset DM1 adults (p = 0,0167). Conclusion: This study shows a differential miR-146a expression in T1D children with respect to T1D adult patients, diminished AICD mechanism in T1D and altered CD4+CD45RA-CD45R0+ memory cells generation in T1D adult patients.

Expression of miR-155, miR-146a, and miR-326 in T1D patients from Chile: relationship with autoimmunity and inflammatory markers

ABSTRACT Objective The aim of this research was to analyze the expression profile of miR-155, miR-146a, and miR-326 in peripheral blood mononuclear cells (PBMC) of 47 patients with type 1 diabetes mellitus (T1D) and 39 control subjects, as well as the possible association with autoimmune or inflammatory markers. Subjects and methods Expression profile of miRs by means of qPCR using TaqMan probes. Autoantibodies and inflammatory markers by ELISA. Statistical analysis using bivariate correlation. Results The analysis of the results shows an increase in the expression of miR-155 in T1D patients in basal conditions compared to the controls (p < 0.001) and a decreased expression level of miR-326 (p < 0.01) and miR-146a (p < 0.05) compared T1D patients to the controls. miR-155 was the only miRs associated with autoinmmunity (ZnT8) and inflammatory status (vCAM). Conclusion Our data show a possible role of miR-155 related to autoimmunity and inflammation in Chilean patients with T1D.

La relación entre obesidad y complicaciones en el curso clínico de las enfermedades respiratorias virales en niños ¿un nuevo factor de riesgo a considerar? / Obesity as a risk factor for complications during acute respiratory infections in children

Obesity has a high prevalence among children. On the other hand, acute respiratory infections especially of viral origin, are an important cause of morbidity and mortality in this age group. During the recent pandemic of influenza A (H1N1) virus, obesity was identified as a novel independent risk factor for severity multiple markers of the disease. We reviewed the evidence associating obesity with a worse course of respiratory diseases in children. Nine out of 40 retrieved articles, were chosen to be reviewed. We concluded that there is evidence suggesting that immunomodulatory effects of obesity could be considered as a novel risk factor. Thus, bearing in mind the drastic rise in obesity prevalence around the world and in Chile, and the latent possibility of new respiratory pandemics caused by viruses, studying the possible effect of obesity aggravating viral respiratory infections will become important.

microRNAs y diabetes tipo 1 / microRNAs and type 1 diabetes

The worldwide increased incidence of type 1 diabetes (T1D) and the decreased genotypes that confer increased risk to T1D indicate a strong environmental impact on the disease. These mechanisms could occur through epigenetic modifications that operate on several gene expression patterns (methylation and acetylation, among others). An alternative mechanism of gene expression inhibition are the microRNAs families. These small noncoding RNAs bind the of mRNAs, downregulating and can downregulate the expression of multiple genes. In this review we discussed the role of certain miRNAs in three characteristics observed in T1D, such as inflammation, autoimmunity and apoptosis.

La metilación global del ADN y los niveles de homocisteína en plasma se encuentran disminuidos en pacientes con diabetes mellitus tipo 1 / Global DNA methylation and homocysteine levels are lower in type 1 diabetes patients

Background: The worldwide rise in the incidence of Type 1 Diabetes (T1D), and the concordance rate between monozygotic twins (50%), indicate a strong effect of the environment as an underlying factor of this disease. This process can occur throughout epigenetic modifications of gene expression such as DNA methylation, in which several nutrients participate as cofactors. Aim: To determine DNA methylation status in T1D patients and if it is related to plasma levels of folates and homocysteine (Hcy). Material and Methods: We obtained blood samples from 25 T1D patients aged 13.7 ± 5.9 years (11 males) and 25 healthy subjects aged 31.1 ± 7.8 years (16 males). DNA methylation was measured using a colorimetric kit in extracted DNA. Results are expressed as median (interquartile range). Results: Compared with healthy controls, T1D patients had lower global DNA methylation (0.85 (0.91) % and 1.25 (1.16) % respectively, p < 0.02) and Hcy levels (4.8 (1.1) µmol/L and 7.3 (1.4) µmol/L respectively p < 0.01). There were no differences in folate levels between groups. A significant association between folates and global DNA methylation status was observed in T1D patients (r = -0.564, p < 0.01) and healthy subjects (r = 0.440, p = 0.03). Conclusions: TD1 patients had lower levels of Hcy and global DNA methylation. It is relevant to further investigate if this imbalance also induces epigenetic changes in a gene-specific manner, especially in key genes involved in T1D pathogenesis.