Inhibitory Actions of Tropeines on the α3 Glycine Receptor Function

Glycine receptors (GlyRs) are chloride-permeable pentameric ligand-gated ion channels. The inhibitory activity of GlyRs is essential for many physiological processes, such as motor control and respiration. In addition, several pathological states, such as hyperekplexia, epilepsy, and chronic pain, are associated with abnormal glycinergic inhibition. Recent studies have pointed out that positive allosteric modulators targeting the GlyR α3 subunit (α3GlyR) displayed beneficial effects in chronic pain models. Interestingly, previous electrophysiological studies have shown that tropeines, which are a family of synthetic antagonists of the serotonin type 3 receptors (5-HT3Rs), potentiate the activity of GlyRs conformed by α1 subunits. However, despite its importance as a pharmacological target in chronic pain, it is currently unknown whether the α3GlyR function is modulated by tropeines. Using electrophysiological techniques and molecular docking simulations, here we show that tropeines are inhibitors of the α3GlyR function. Tropisetron, a prototypical tropeine, exerted concentration-dependent inhibitory effects on α3GlyRs at the low micromolar range. In addition, three other tropeines showed similar effects. Single-channel recordings show that tropisetron inhibition is associated with a decrease in the open probability of the ion channel. Molecular docking assays suggest that tropeines preferentially bind to an agonist-free, closed state of the ion channel. The tropeine binding occurs in a discrete pocket around the vicinity of the orthosteric site within the extracellular domain of α3GlyR. Thus, our results describe the pharmacological modulation of tropeines on α3GlyRs. These findings may contribute to the development of GlyR-selective tropeine derivatives for basic and/or clinical applications

Modulation of GABAA receptors and of GABAergic synapses by the natural alkaloid gelsemine

The Gelsemium elegans plant preparations have shown beneficial activity against common diseases, including chronic pain and anxiety. Nevertheless, their clinical uses are limited by their toxicity. Gelsemine, one of the most abundant alkaloids in the Gelsemium plants, have replicated these therapeutic and toxic actions in experimental behavioral models. However, the molecular targets underlying these biological effects remain unclear. The behavioral activity profile of gelsemine suggests the involvement of GABAA receptors (GABAARs), which are the main biological targets of benzodiazepines (BDZs), a group of drugs with anxiolytic, hypnotic, and analgesic properties. Here, we aim to define the modulation of GABAARs by gelsemine, with a special focus on the subtypes involved in the BDZ actions. The gelsemine actions were determined by electrophysiological recordings of recombinant GABAARs expressed in HEK293 cells, and of native receptors in cortical neurons. Gelsemine inhibited the agonist-evoked currents of recombinant and native receptors. The functional inhibition was not associated with the BDZ binding site. We determined in addition that gelsemine diminished the frequency of GABAergic synaptic events, likely through a presynaptic modulation. Our findings establish gelsemine as a negative modulator of GABAARs and of GABAergic synaptic function. These pharmacological features discard direct anxiolytic or analgesic actions of gelsemine through GABAARs but support a role of GABAARs on the alkaloid induced toxicity. On the other hand, the presynaptic effects of the alkaloid provide an additional mechanism to explain their beneficial effects. Collectively, our results contribute novel information to improve understanding of gelsemine actions in the mammalian nervous system

Clinical simulation with dramatization, a teaching-learning strategy for undergraduate students of nutrition and dietetics

At present, education in Health Sciences requires interaction with real patients, which is made more complex due to the need to ensure their health safety. For this reason, new teaching methodologies are now being implemented, which help to improve and protect safe care. Objective: This study was carried out using a quantitative approach with a non-experimental, descriptive design. Materials and Methods: The sample was non-probabilistic and consisted of 87 undergraduate students. A questionnaire was used, with 18 statements divided into 3 dimensions: dimension 1, simulation structure, with six questions reflecting aspects related to its implementation; dimension 2, learning, with seven questions related to aspects of effective communication, trust, learning and respect for diversity; dimension 3, feedback for learning, with five questions, including feedback by the teacher and the simulated patient, as well as their own views with regard to participating in another similar experience again. A five-point Likert scale was used. Results: The three dimensions studied, simulation structure, learning and feedback for learning, report a high level of positive perceptions. Conclusion: The simulation strategy is an educational tool in health-related careers that enhances the clinical competencies of the students as well as the relevant theoretical and practical skills and abilities in their learning process, promoting integration of the knowledge acquired in previous subjects

Nutrition education intervention for children with cancer and their parents

Pediatric cancer in Chile is the leading cause of death resulting from disease in children, with an incidence of 14.5 per 100,000 children under 15 years of age. Overweight or obesity can be a possible side effect of treatment, and parents are key agents in influencing child habits. In this study, an educational program on healthy eating was developed directed at parents of children with cancer with the aim of contributing positively to diet quality. Twelve children with cancer were involved in the research together with their parents/guardians. A nutritional evaluation was carried out considering weight, height, waist circumference and skin folds. Diet was analyzed based on a 24-hour dietary recall, a 3-day diet diary and a frequency consumption survey (initial/final). Six nutrition education sessions were carried out. The results show a high prevalence of overweight and abdominal obesity, along with a high intake of candy, pastry products and sugary beverages, coupled with a low intake of fruit, vegetables, fish and water. After conducting educational intervention, a decrease in the consumption of unhealthy foods and an increase in healthy foods was achieved. Children with cancer in our sample had high levels of overweight and obesity and unhealthy eating habits, which is consistent with the results of a large part of studies carried out in this population. This can, however, be positively modified by engaging them and their parents/ guardians in nutrition education

From farm to fork: it could be the case of Lactic Acid Bacteria in the stimulation of folates biofortification in food crops

B-group vitamins are essential nutrients for living organisms. Despite that B-group vitamins are present in a multiplicity of foods, vitamin deficiency in human still occur in many countries, mainly by inadequate food intake and unbalanced diets. To overcome this global health problem, chemistry food supplementation is a widely used alternative. Moreover, in the specific case of folic acid, the biofortification with the natural folate form 5-methyltetrahydrofolate (5-MTHF), found in vegetables and produced by certain bacterial taxa such is the case of Lactic Acid Bacteria (LAB), would be a more efficient and secure alternative than the food supplementation of foods with folic acid. This review recommends the possibility to use LAB as an economically sustainable and environmentally friendly plant probiotic in order to produce vitamins biofortificated crops. This new approach could lead something interesting in two aspects: on one hand, the promotion of plant growth, and on the other hand, a biofortificated food crop for human nutrition and health safety to food security

VOLATILE PROFILE AND CONSUMER ACCEPTABILITY OF NATURAL YOGHURTS ELABORATED WITH CHILEAN NATIVE CULTURES OF ENTEROCOCCUS SP. STRAIN BB3 AND LACTOBACILLUS SP. STRAIN BB6

According to WHO, in 2016 around 13% of the world's adult population (11% of men and 15% of women) were obese. The global prevalence of obesity almost tripled between 1975 and 2016. In this context, it is important to note that the continuous increase in life expectancy, the desire for a better quality of life, and the high cost of medical care have led to a growing demand for functional foods in the market. People have started to realize that their food choices and their unhealthy lifestyles have consequences for their health. An important role in this scenario is associated with functional foods containing probiotic strains, reported to benefit human health. Here we report the development of natural yogurts based on native probiotic starter cultures of Enterococcus sp. strain BB3 (MK681869) and Lactobacillus sp. strain BB6 (MK681868), isolated from raw cow milk of La Araucania region of Chile. The odor and taste were the main parameters criticized by the consumer, the analysis of CG-MS elucidated that the yogurt produced by the strain Enterococcus sp. strain BB3 (MK681869) produced a higher amount of heptan-2-one, associated with a cheesy type odor, with less acceptance by the consumers. The acceptability of 6 types of yogurt was evaluated with a randomized analysis of 60 participants. The development of a functional dairy product based on probiotics is of interest because of its relation with positive changes in gut microbiota, and at the same time with a possible decrease in body weight

Weight stigma of nutrition and dietetics students towards people with obesity

Weight bias is present in different scenarios, one of them is the area of health on the part of its professionals. For this reason, the aim of this descriptive, observational and cross-sectional study was to determine whether weight bias towards people with obesity was observed among students of the Nutrition and Dietetics career of the Catholic University of Temuco and to provide corrective measures to prevent the bias. The participants of this study were 94 nutrition and dietetics undergraduate students from different years of study. Students answered the GAMS 27-Obesity. According to the results obtained in this study, future nutritionists have a predisposition to weight bias towards people with obesity, this can have a negative impact on the care of these patients. Implementing corrective measures, during professional training, can prevent weight bias towards people with obesity by future professionals, thus improving their quality of care and positively impacting the health of these people

Eating patterns in children with autism spectrum disorder

The purpose of this research was to analyze the eating patterns of preschool- and school-aged children with ASD, as provided by their families, in the La Araucanía Region of Chile. It involved a cross-sectional study with 72 families with children diagnosed with ASD aged between 2 and 12 years old. Food selectivity, appetite, body mass index (BMI) and frequency of food consumption were studied. The research determined that 97.67% present food selectivity, corresponding to alterations in the frequency of consumption of specific food groups. Moreover, 93.06%, 90.28%, 80.56% and 62.50% of children in the study do not meet the daily recommendations for fruit, fish, water and vegetable consumption, respectively. Therefore, it is important for these findings to be considered when designing and carrying out educational interventions regarding food in families with children with ASD for greater assertiveness and effectiveness in improving health

El Síndrome de Quemarse por el Trabajo (SQT) en profesores de colegios privados y liceos técnicos de Santiago de Chile

El estrés laboral es uno de los problemas más afecta la calidad de vida. Los profesores del sistema educacional no están exentos de los impactos negativos que les produce un tipo de estrés: Síndrome de Burnout. Este se caracteriza por altos niveles de despersonalización, agotamiento emocional y pérdida de realización personal. El propósito fue describir el Síndrome de Burnout en profesores de colegios privados y de liceos técnicos de Santiago. A 114 profesores se les aplicó un test de Burnout. No se encontró presencia del síndrome en los sujetos ni tampoco diferencias significativas entre docentes de establecimientos educacionales privados versus profesores de liceos técnicos. Se sugiere realizar investigaciones cualitativas en los factores personales, grupales y organizacionales relativos al burnout

Changes in bacterial communities by post-emergent herbicides in an Andisol fertilized with urea as revealed by DGGE

Large amounts of urea and various herbicides are applied to Chilean Andisols by farmers; however, how different herbicide types affect bacterial communities in urea-fertilized soils remains unknown. In this study, the effect of post-emergent herbicides (MCPA, flumetsulam, fluroxypyr, triclopyr, clopyralid and picloram) on total bacterial (TB) and ammonia-oxidizing bacteria (AOB) communities was investigated in a urea-fertilized soil microcosm using denaturing gradient gel electrophoresis at days 1 and 15 of incubation. The residual concentrations of herbicides in microcosm soils were measured by high-performance liquid chromatography. Differences in bacterial communities were analyzed and visualized with non-metric multidimensional scaling. All of the tested herbicides decreased in microcosm soils, reaching 46–98% of dissipation at 15 days. Changes in the TB and AOB communities were variable, depending on the urea and herbicide dosage, herbicide type and sampling time. Under the recommended dose of urea (570 mg kg?1 soil), soils that were treated with MCPA and triclopyr showed significant changes in TB and AOB community structures compared to control soils at both sampling times. When a 2-fold-higher recommended dose of urea (1140 mg kg?1 soil) was applied, the TB communities were mainly affected by flumetsulam and picloram at both sampling times. Changes in the AOB communities were mainly observed in soils that were treated with MCPA and fluroxypyr under both urea doses. This study determined which herbicides (and doses) significantly affect the bacterial communities in urea-fertilized soils. This evidence can be very useful when management practices are being designed, revised and/or established in Andisols