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Introduction: obesity is a cardiometabolic risk (CMR) factor in adolescents. It represents a public health problem that requires simple diagnostic strategies based on the determination of anthropometric indicators (AIs) such as body mass index (BMI), waist circumference (WC), conicity index (CONI), waist-to-height ratio (WHtR), and body fat percentage (BFP). The purpose of the current contribution was to analyze the utility of the aforementioned AIs for evaluating obesity as a CMR factor in Mexican adolescents. Materials and methods: the design of the study is descriptive and cross-sectional. Nutritional status was established by using various AIs and as a CMR factor under the criteria of WHtR. Participating in the present investigation were 2,000 adolescents from 15 to 17 years of age, of which 1,079 (53.9 %) were female and 921 (46.1 %) were male. All were high school students in Tuxtla Gutiérrez, Chiapas, Mexico. Results and conclusion: the prevalence of obesity was influenced by gender. With the WHtR and BFP, male students exhibited a greater prevalence of obesity, while with the BMI and CONI, the percentage of obesity was similar between the two genders. BMI was significantly correlated with BFP, WC and WHtR, and was one of the AIs with the greatest area under the curve, showing a good capacity to predict cardiometabolic risk. BMI is a simple and adequate tool for diagnosing obesity and predicting CMR in adolescents.Introducción: la obesidad es un factor de riesgo cardiometabolico (RCM) en los adolescentes y representa un problema de salud pública que requiere estrategias diagnosticas sencillas, basadas en la determinación de indicadores antropométricos (IA) como el índice de masa corporal (IMC), la circunferencia de la cintura (CC), el índice de conicidad (ICONI), el índice de cintura-talla (ICT) y el porcentaje de grasa corporal (PGC). El propósito del presente estudio fue analizar la utilidad de diversos IA (IMC, CC, ICONI, ICT y PGC) para evaluar la obesidad como factor de RCM en adolescentes mexicanos. Materiales y métodos: el diseño del estudio fue descriptivo y transversal. Se analizó el estado nutricional mediante varios IA y el factor de RCM bajo los criterios del ICT. Este estudio fue conducido en 2000 adolescentes de entre 15 y 17 años, de los cuales 1079 (53,9 %) eran mujeres y 921 (46,1 %) varones, todos ellos estudiantes de nivel medio superior de Tuxtla Gutiérrez, Chiapas, México. Resultados y conclusión: la prevalencia de la obesidad estuvo influenciada por el género: los varones presentaron una mayor prevalencia de obesidad con ICT y PGC, mientras que con IMC e ICONI, el porcentaje de obesidad fue similar entre ambos géneros. El IMC se correlacionó significativamente con el PGC, la CC y el ICT, y fue uno de los IA con mayor área bajo la curva, mostrando una buena capacidad para predecir el RCM. El IMC representa una herramienta sencilla y adecuada para el diagnóstico de obesidad y predecir el RCM en adolescentes.

One of the main hallmarks of Alzheimer's disease includes the neurofibrillary tangles formation produced by hyperphosphorylation of the Tau protein, whose expression is putatively regulated by the ovarian hormones estradiol and progesterone. Hippocampus is a brain region that participates in many functions related to learning and memory; in addition, it is abundant in both estradiol and progesterone receptors. In this study, we explore the expression of Tau hyperphosphorylation at hippocampus and the performance of rats in an autoshaping learning task at 5, 10 and 15 months after the ovaries removal. In these animals, ovariectomy was performed at 3 months of age. These data were compared with those derived from intact rats at 8, 13 and 18 months old. A clear decrease in the number of conditioned responses of both intact and ovariectomized rats in the autoshaping learning task was observed. The interaction of both factors confirms that, in this test, learning varies depending on aging and the presence or absence of ovaries. A progressive increase in hippocampal Tau phosphorylation at Ser-396 was observed in either intact or ovariectomized rats. Interestingly, an interaction between the analyzed factors shows that such hyperphosphorylation was potentiated by the absence of ovaries. These results emphasize the importance of aging and the lack of ovarian hormones for an associative learning test and for the expression of one of the most important hallmarks of Alzheimer's disease.

Estrogen depletion due to aging, surgery or pathological events can cause a multitude of problems, including neurodegenerative alterations. In rodents without ovaries, 17-beta estradiol (E2) has been shown to produce beneficial effects on cognition, stimulating brain regions (e.g., the neocortex, hippocampus and amygdala) related to cognition and learning. Another treatment that stimulates these brain regions is an enriched environment (EE), which is a complex set of external factors in the immediate surroundings that facilitates greater stimulation of sensorial, cognitive and motor circuits of the brain. The aim of the present study was to test, using an animal model of ovariectomy-induced impairment of memory, the relative effect of E2 (with a time-released pellet; 1 μg/rat/day), EE exposure and a combination of both treatments. Experimental and control groups were submitted to two memory tests 18 weeks post-surgery: the autoshaping learning task (ALT) for measuring associative learning and the novel object recognition test (NORT) for evaluating short- and long-term memory. To assess potential motor impairments caused by treatments, all rats were tested after the ALT in an automatic activity counter. Results from ALT show that the ovariectomy blocked the conditioned responses displayed, an effect rescued by chronic treatment with estrogen or EE exposure. The combination of both treatments did not improve the results obtained separately. In the NORT, the exploration time for recognizing a novel object was similar in the short run with all groups, but greater in the long run with hormone administration or EE exposure. As with the ALT, in the NORT there was no improvement shown by the combination treatment. These data were not masked by changes in spontaneous activity because this parameter was not modified in the rats by either treatment. Possible action mechanisms are proposed, taking into account the role of corticosterone and BDNF on cognition.

espanolIntroduccion: los indicadores antropometricos (IA) como la circunferencia de cintura (CC), el indice de masa corporal (IMC), el indice cintura/ cadera (ICC), el indice cintura/talla (ICT) y el porcentaje de grasa corporal (PGC) son herramientas utiles para el diagnostico del estado nutricional (EN) en los adolescentes. Sin embargo, cada uno de estos IA presentan ventajas y desventajas. El proposito del presente estudio fue analizar la asociacion de los IA (IMC, CC, ICC, ICT y PGC) para evaluar el EN y estimar el riesgo cardiometabolico (RCM) en adolescentes mexicanos. Material y metodo: el diseno del estudio fue descriptivo transversal. Se analizo el EN a traves de diversos IA y el RCM bajo los criterios de ICT. Este estudio fue conducido en 917 adolescentes de entre 15 y 17 anos, de los cuales 488 (52,9%) eran mujeres y 429 (47,1%) varones, todos estudiantes de nivel medio superior de Tuxtla Gutierrez, Chiapas, Mexico. Resultados y conclusion: las mujeres presentaron mayor prevalencia de obesidad con la mayoria de los IA utilizados. El ICT fue el IA que detecto mayor prevalencia de obesidad (31%), correlacionandose con el IMC y el PGC. Ademas, se evidencio una asociacion significativa entre el EN valorado por todos los IA y el RCM. El ICT podria ser considerado como una herramienta adecuada para el diagnostico de obesidad asociada a RCM en adolescentes. EnglishIntroduction: anthropometric indicators (AIs) such as waist circumference (WC), body mass index (BMI), waist/hip index (WHpI), waist/height index (WHtI) and body fat percentage (BFP) are useful tools for the diagnosis of nutritional status (NS) in adolescents. Each of these parameters has advantages and disadvantages. The purpose of the present study was to analyze the association of these AIs (WC, BMI, WHpI, WHtI, and BFP) to evaluate nutritional status and estimate the cardiometabolic risk (CMR) in Mexican adolescents. Material and method: in a cross-sectional descriptive study, the NS was analyzed through various AIs and CMR with the WHtI criteria. Nine hundred and seventeen adolescents between 15 and 17 years old participated in the study, of whom 488 (52.9%) were female and 429 (47.1%) male, all students of middle school in Tuxtla Gutierrez, Chiapas, Mexico. Results and conclusion: women presented a higher prevalence of obesity according to most indicators. The WHtI was the parameter that detected the highest prevalence of obesity (31%), correlating with the BMI and the BFP. Moreover, there was evidence of a significant relation between NS (assessed by all the anthropometric indicators) and CMR. The WHtI could be considered as an adequate tool for the diagnosis of obesity associated with CMR in adolescents.

Treatment with 17-β estradiol and progesterone improves the performance of ovariectomized rats in an autoshaping learning task, representing cognitive improvement. To test whether this is attributable to genomic mechanisms, the antiestrogen ICI 182 780 or antiprogesterone RU486 was injected into ovariectomized animals primed previously with estrogen or progesterone, respectively. Compared with the vehicle control, each hormone administered alone produced an elevated expression of choline acetyltransferase and TrkA, along with an improvement in performance on the behavioral test. E2+ICI reverted the increase in these two proteins. However, RU alone elicited higher ChAT expression. With this exception, there was a clear linear regression between the number of conditioned responses and the level of ChAT and TrkA in the basal forebrain. The results suggest that TrkA may be more important than ChAT for regulating autoshaping learning tasks, and that genomic mechanisms in the basal forebrain could possibly underlie hormonal improvement of cognition.

Hormone replacement therapy (HRT) may be prescribed to prevent the symptoms of menopause. This therapy may include estrogenic and/or progestin components and may increase the incidence of endometrial and breast cancers. Tibolone (TIB), which is also made up of estrogen and progestin components, is often used to reduce the impact of HRT. However, the effect of TIB on the processes of learning, memory and anxiety has yet to be fully elucidated. The aim of this study was to evaluate the long-term effect on learning, memory processes and anxiety in ovariectomized rats caused by different doses of TIB (0 mg/kg, 0.01 mg/kg, 0.1 mg/kg 1.0 mg/kg and 10 mg/kg, administered daily via the oral route for 18 weeks). Two behavioral animal models, the autoshaping and T maze models were employed. The concentrations of acetyl choline transferase (ChAT) and tryptophan hydroxylase (TPH) in the hippocampus were directly measured by Western blot. No significant changes were observed in the autoshaping model and spontaneous activity test. In the T maze, increased latency was observed with TIB doses of 1 and 10 mg/kg compared to the vehicle. We observed that the ChAT content decreased with increasing doses of TIB, whereas TPH content increased with doses of 1 and 10 mg/kg of TIB. These data indicate that high doses of TIB improved emotional learning, which may be related to the modulation of the cholinergic and serotonergic systems by TIB.

Aims We analyzed the effects of the short- and long-term administration of estradiol (E2) or progesterone (P4) after ovariectomy on the expression of MAP2, Tau and GFAP in prefrontal cortex and hippocampus. Main methods Sprague Dawley rats were ovariectomized and immediately treated with E2 or P4 for 2 or 18 weeks. At the end of treatments, hippocampus and prefrontal cortex were excised, proteins were extracted and MAP2, Tau and GFAP were analyzed by Western blot. Key findings MAP2 and Tau content was not modified by E2 in the prefrontal cortex. On the contrary, P4 decreased MAP2 content after a short-term treatment, while it increased that of MAP2 and TAU in this brain region after a long-term treatment. E2 increased MAP2 content in hippocampus. In this region, short-term administration of P4 increased that of MAP2. GFAP content was diminished after a long-term administration of P4 in hippocampus. Significance Current data emphasize the importance of short- and long-term sex steroid treatment on neuronal and glial cytoskeletal proteins expression.

It has been proposed that sex steroid hormones improve performance in some cognitive tasks by regulating the basal forebrain cholinergic function. However, the molecular basis of such influence still remains unknown. Current study analyzed the performance of ovariectomized rats in an autoshaping learning task after a short-term treatment with 17β-estradiol (E2: 4 and 40μg/kg) and/or progesterone (P4: 4mg/kg). These results were correlated with basal forebrain choline acetyltransferase (ChAT) and TrkA protein content. The high dose of E2 enhanced both acquisition in the autoshaping task and the content of ChAT and TrkA. P4 treatment increased ChAT and TrkA content without affecting performance of rats in the autoshaping learning task. Interestingly, the continuous and simultaneous administration of E2 plus P4 did not significantly modify behavioral and biochemical evaluated parameters. These results address the influence of both E2 and P4 on cholinergic and TrkA activity and suggest that the effects of ovarian hormones on cognitive performance involve basal forebrain cholinergic neurons.