The Role of Vesicular Glutamate Transporter Type 3 in Social Behavior, with a Focus on the Median Raphe Region.

Social behavior is important for our well-being, and its dysfunctions impact several pathological conditions. Although the involvement of glutamate is undeniable, the relevance of vesicular glutamate transporter type 3 (VGluT3), a specific vesicular transporter, in the control of social behavior is not sufficiently explored. Since midbrain median raphe region (MRR) is implicated in social behavior and the nucleus contains high amount of VGluT3+ neurons, we compared the behavior of male VGluT3 knock-out (KO) and VGluT3-Cre mice, the latter after chemogenetic MRR-VGluT3 manipulation. Appropriate control groups were included. Behavioral test battery was used for social behavior (sociability, social discrimination, social interaction, resident intruder test) and possible confounding factors (open field, elevated plus maze, Y-maze tests). Neuronal activation was studied by c-Fos immunohistochemistry. Human relevance was confirmed by VGluT3 gene expression in relevant human brainstem areas. VGluT3 KO mice exhibited increased anxiety, social interest, but also aggressive behavior in anxiogenic environment and impaired social memory. For KO animals, social interaction induced lower cell activation in the anterior cingulate, infralimbic cortex, and medial septum. In turn, excitation of MRR-VGluT3+ neurons was anxiolytic. Inhibition increased social interest 24 h later but decreased mobility and social behavior in aggressive context. Chemogenetic activation increased the number of c-Fos+ neurons only in the MRR. We confirmed the increased anxiety-like behavior and impaired memory of VGluT3 KO strain and revealed increased, but inadequate, social behavior. MRR-VGluT3 neurons regulated mobility and social and anxiety-like behavior in a context-dependent manner. The presence of VGluT3 mRNA on corresponding human brain areas suggests clinical relevance.

The Dopaminergic Cells in the Median Raphe Region Regulate Social Behavior in Male Mice.

According to previous studies, the median raphe region (MRR) is known to contribute significantly to social behavior. Besides serotonin, there have also been reports of a small population of dopaminergic neurons in this region. Dopamine is linked to reward and locomotion, but very little is known about its role in the MRR. To address that, we first confirmed the presence of dopaminergic cells in the MRR of mice (immunohistochemistry, RT-PCR), and then also in humans (RT-PCR) using healthy donor samples to prove translational relevance. Next, we used chemogenetic technology in mice containing the Cre enzyme under the promoter of the dopamine transporter. With the help of an adeno-associated virus, designer receptors exclusively activated by designer drugs (DREADDs) were expressed in the dopaminergic cells of the MRR to manipulate their activity. Four weeks later, we performed an extensive behavioral characterization 30 min after the injection of the artificial ligand (Clozapine-N-Oxide). Stimulation of the dopaminergic cells in the MRR decreased social interest without influencing aggression and with an increase in social discrimination. Additionally, inhibition of the same cells increased the friendly social behavior during social interaction test. No behavioral changes were detected in anxiety, memory or locomotion. All in all, dopaminergic cells were present in both the mouse and human samples from the MRR, and the manipulation of the dopaminergic neurons in the MRR elicited a specific social response.

Ovariectomy-induced hormone deprivation aggravates Aß1-42 deposition in the basolateral amygdala and cholinergic fiber loss in the cortex but not cognitive behavioral symptoms in a triple transgenic mouse model of Alzheimer's disease.

Alzheimer's disease is the most common type of dementia, being highly prevalent in elderly women. The advanced progression may be due to decreased hormone synthesis during post-menopause as estradiol and progesterone both have neuroprotective potentials. We aimed to confirm that female hormone depletion aggravates the progression of dementia in a triple transgenic mouse model of Alzheimer's disease (3xTg-AD). As pathological hallmarks are known to appear in 6-month-old animals, we expected to see disease-like changes in the 4-month-old 3xTg-AD mice only after hormone depletion. Three-month-old female 3xTg-AD mice were compared with their age-matched controls. As a menopause model, ovaries were removed (OVX or Sham surgery). After 1-month recovery, the body composition of the animals was measured by an MRI scan. The cognitive and anxiety parameters were evaluated by different behavioral tests, modeling different aspects (Y-maze, Morris water maze, open-field, social discrimination, elevated plus maze, light-dark box, fox odor, operant conditioning, and conditioned fear test). At the end of the experiment, uterus was collected, amyloid-ß accumulation, and the cholinergic system in the brain was examined by immunohistochemistry. The uterus weight decreased, and the body weight increased significantly in the OVX animals. The MRI data showed that the body weight change can be due to fat accumulation. Moreover, OVX increased anxiety in control, but decreased in 3xTg-AD animals, the later genotype being more anxious by default based on the anxiety z-score. In general, 3xTg-AD mice moved less. In relation to cognition, neither the 3xTg-AD genotype nor OVX surgery impaired learning and memory in general. Despite no progression of dementia-like behavior after OVX, at the histological level, OVX aggravated the amyloid-ß plaque deposition in the basolateral amygdala and induced early cholinergic neuronal fiber loss in the somatosensory cortex of the transgenic animals. We confirmed that OVX induced menopausal symptoms. Removal of the sexual steroids aggravated the appearance of AD-related alterations in the brain without significantly affecting the behavior. Thus, the OVX in young, 3-month-old 3xTg-AD mice might be a suitable model for testing the effect of new treatment options on structural changes; however, to reveal any beneficial effect on behavior, a later time point might be needed.

Median raphe region GABAergic neurons contribute to social interest in mouse.

Gamma-aminobutyric acid (GABA) is a well-known inhibitory neurotransmitter implicated in numerous physiological and pathological behaviors including social interest. Dysregulation of the median raphe region (MRR), a main serotoninergic nucleus, is also characterized by increased social problems. As the majority of MRR cells are GABAergic, we aimed to reveal the social role of these cells. Chemogenetic techniques were used in vesicular GABA transporter Cre mice and with the help of adeno-associated virus vectors artificial receptors (DREADDs, stimulatory, inhibitory or control, containing only a fluorophore) were expressed in MRR GABAergic cells confirmed by immunohistochemistry. Four weeks after viral injection a behavioral test battery (sociability; social interaction; resident-intruder) was conducted. The artificial ligand (clozapine-N-oxide, 1 mg/10 ml/kg) was administrated 30 min before the tests. As possible confounding factors, locomotion (open field/OF), anxiety-like behavior (elevated plus maze/EPM), and short-term memory (Y-maze) were also evaluated. Stimulation of the GABAergic cells in MRR had no effect on locomotion or working and social memory; however, it increased social interest during sociability and social interaction but not in resident-intruder tests. Accordingly, c-Fos elevation in MRR-GABAergic cells was detected after sociability, but not resident-intruder tests. In the EPM test, the inhibitory group entered into the open arms later, suggesting an anxiogenic-like tendency. We confirmed the role of MRR-GABAergic cells in promoting social interest. However, different subpopulations (e.g. long vs short projecting, various neuropeptide containing) might have divergent roles, which might remain hidden and requires further studies.

Análise comparativa de fórmulas preditivas de avaliação da capacidade funcional com o teste cardiopulmonar de jogadoras de futebol profissional / Análisis comparativo de fórmulas predictivas de evaluación de la capacidad funcional con la prueba cardiopulmonar de jugadoras de fútbol profesional / Comparative analysis of predictive formulas for the evaluation of functional capacity with cardiopulmonary test in professional female soccer players

RESUMO Comparar a validade de duas fórmulas de predição do consumo de oxigênio (VO2) com os valores obtidos no teste cardiopulmonar (TCP) em esteira ergométrica de jogadoras de futebol profissional. Dezoito jogadoras de futebol profissional foram submetidas ao TCP em esteira em um protocolo de carga incremental. Na sequência, foi determinado o VO2 da potência do limiar anaeróbio ventilatório (LAV) e no pico do exercício físico. Posteriormente, as fórmulas de predição de VO2 - i) VO2 = (0,2 x velocidade) + (0,9 x velocidade x inclinação) + 3,5 - velocidade em mph e inclinação %); e ii) MET (equivalente metabólica) = 6xHRI-5, onde HRI = frequência cardíaca máxima/frequência cardíaca de repouso - foram aplicadas nas mesmas potências para comparação. Para a primeira fórmula foi observado que tanto no LAV como no pico do TCP, os dados obtidos ficaram abaixo do previsto, sugerindo que a fórmula superestima o VO2 e, consequentemente, a capacidade e a potência aeróbicas. Na segunda fórmula foi observado que os valores ficaram abaixo do obtido, sugerindo que a fórmula subestimou o VO2 e, consequentemente a potência aeróbica, e mais uma vez a capacidade funcional. Diante disso, as fórmulas de predição não mostraram similaridade na determinação da capacidade funcional (CF) de jogadoras de futebol profissional, sugerindo não serem recomendadas para essa população.

RESUMEN Comparar la validez de dos fórmulas para predecir el consumo de oxígeno (VO2) con los valores obtenidos en la prueba cardiopulmonar (PCP) en una cinta de correr de jugadoras de fútbol profesionales. Dieciocho jugadoras de fútbol profesional se sometieron al PCP en cinta de correr en un protocolo de carga incremental. En la secuencia, se determinó el VO2 de la potencia del Umbral Anaeróbico Ventilatorio (UAV) y en el pico del ejercicio físico. Posteriormente, las fórmulas de predicción de VO2 -i) VO2 = (0,2 × velocidad) + (0,9 × velocidad × inclinación) + 3,5 − velocidad en mph e inclinación %); y ii) MET (equivalente metabólico) = 6xHRI−5, donde HRI = frecuencia cardiaca máxima/frecuencia cardíaca de reposo- se aplicaron en las mismas potencias para comparación. Para la primera fórmula se observó que tanto en la UAV como en el pico del PCP, los datos obtenidos quedaron por debajo de lo previsto, sugiriendo que la fórmula sobrestima el VO2 y, consecuentemente, la capacidad y la potencia aeróbica. En la segunda fórmula se observó que los valores quedaron por debajo de lo obtenido, sugiriendo que la fórmula subestimó el VO2 y, consecuentemente, la potencia aeróbica, y una vez más la capacidad funcional. Por lo tanto, las fórmulas de predicción no mostraron semejanza en la determinación de la capacidad funcional (CF) de las jugadoras de fútbol profesional, sugiriendo que no son recomendadas para esa población.

ABSTRACT To compare the validity of two oxygen consumption (VO2) prediction formulas with the values obtained through cardiopulmonary exercise test (CPT) in a treadmill with professional female soccer players. Eighteen professional female soccer players performed CPT in a treadmill with an incremental protocol. The VO2 of the gas exchange threshold (GET) was determined, as well as at peak exercise. After that, the following formula of VO2prediction i) VO2 = (0.2 x velocity) + (0.9 x velocity x incline) + 3.5 - velocity, in mph and %incline); and ii) MET (metabolic equivalent) = 6xHRI-5, where HRI = maximum heart rate/resting heart rate, were applied in the same power for comparison. In the first formula, the values obtained in GET and at peak exercise were below the estimated, indicating that the formula overestimated VO2 and, consequently, aerobic capacity and power. In the second formula, the values were below the estimated, indicating that the formula also underestimated VO2 and, consequently, aerobic capacity and power. Given these results, the prediction formulas do not present similarity in determining the functional capacity (FC) of professional female soccer players, indicating they are not suitable for this population.

INFLUÊNCIA DO HÁBITO DE EXERCÍCIO NA INFÂNCIA E ADOLESCÊNCIA NA FLEXIBILIDADE DE ADULTOS SEDENTÁRIOS / INFLUENCE OF EXERCISE HABITS DURING CHILDHOOD AND ADOLESCENCE ON FLEXIBILITY OF SEDENTARY ADULTS / INFLUENCIA DE LOS HÁBITOS DE EJERCICIO EN LA INFANCIA Y LA ADOLESCENCIA SOBRE LA FLEXIBILIDAD DE ADULTOS SEDENTARIOS

RESUMO Introdução: A flexibilidade corporal é um dos componentes da aptidão física relacionada com a saúde e desempenho físico. Esse componente tende a diminuir com o envelhecimento, sendo passível de modificação por treinamento específico; por outro lado, essas adaptações favoráveis tendem a desaparecer com destreinamento. Objetivo: Avaliar a influência do histórico de exercício físico e/ou participação desportiva competitiva na juventude sobre a flexibilidade corporal em adultos que foram pouco ativos ou sedentários nos últimos cinco anos. Métodos: Análise retrospectiva de 1.388 indivíduos avaliados entre 2012 e 2015. Após aplicação de critérios de exclusão, a amostra final incluiu 533 adultos (63,6% homens; 20-94 anos de idade) pouco ativos ou sedentários nos últimos cinco anos. Em uma breve entrevista foram obtidos os perfis de exercício físico na infância/adolescência (PEFIA) e nos últimos cinco anos de vida. Esses perfis foram agrupados em três categorias, em função da quantidade mínima de exercício recomendado para cada idade, como: abaixo, adequado ou acima. A flexibilidade foi avaliada pelo Flexiteste e o flexíndice (FLX) foi calculado - somatório dos resultados da mobilidade passiva de cada um dos 20 movimentos articulares medidos (escala de 0 a 4) -, que foi posteriormente ajustado por idade e sexo por percentis (P-FLX) (Araújo, 2008). Resultados: Homens e mulheres adultos fisicamente inativos nos últimos cinco anos tiveram P-FLX medianos, respectivamente, de 25 e 35. Quando classificados pelo PEFIA, não foram observadas diferenças entre homens (P=0,23) e mulheres (P=0,10) no P-FLX. Conclusão: A flexibilidade de adultos pouco ativos ou sedentários nos últimos cinco anos, quando avaliada pelo FLX, é inferior à prevista para a idade e não é influenciada pelo PEFIA, indicando que o sedentarismo recente é prejudicial à flexibilidade global e que um histórico de mais exercício e/ou esporte na juventude não parece prevenir essa deficiência.

ABSTRACT Introduction: Flexibility is one of the components of performance and health-related physical fitness. This component tends to decrease with aging, but can be modified through specific physical training; on the other hand, these favorable adaptations tend to disappear with detraining. Objective: To evaluate the influence of physical exercise and/or participation in competitive sports during childhood and adolescence on flexibility in adults who have been mostly inactive, or sedentary in the last five years. Methods: Retrospective analysis of 1,388 subjects evaluated between 2012 and 2015. After applying the exclusion criteria, the final sample comprised a total of 533 adults (63.6% men; 20-94 years old), mostly inactive or sedentary over the last five years. The childhood and youth physical exercise profile (CYPEP) and profile of exercise in the last five years were obtained in a brief interview. These data were classified into three categories, according to the minimum recommended exercise for the specific age group, into: below, adequate and above. Flexibility was assessed by the Flexitest, and the flexindex (FLX) was calculated, as the sum total of the results of passive mobility of each of the 20 joint movements measured (scale of 0 to 4); the FLX was then adjusted by age and sex reference percentiles (P-FLX) (Araújo, 2008). Results: Men and women who had been physically inactive for the last five years showed median P-FLX, respectively, of 25 and 35. Using the three CYPEP categories, there were no differences between men (P=.23) and women (P=.10) in P-FLX. Conclusion: When evaluated by the FLX, adults who had been mostly inactive, or sedentary in the last five years showed lower levels of flexibility compared to their age-reference values, which were not influenced by CYPEP, indicating that a recent sedentary lifestyle compromised overall flexibility, and that a more activity pattern of exercise and sports during youth is unable to prevent this deficiency.

RESUMEN Introducción: La flexibilidad es uno de los componentes de la aptitud física relacionada con la salud y el rendimiento físico. Este componente tiende a disminuir con la edad y puede ser modificado por el entrenamiento específico; por otra parte, estos ajustes favorables tienden a desaparecer con desentrenamiento. Objetivo: Evaluar la influencia de la historia de ejercicio físico y/o la participación en competencias deportivas en la juventud sobre la flexibilidad de los adultos menos activos o sedentarios en los últimos cinco años. Métodos: Análisis retrospectivo de 1.388 sujetos evaluados entre 2012 y 2015. Después de los criterios de exclusión, la muestra final fue de 533 adultos (63,6% hombres; 20-94 años) poco activos o sedentarios en los últimos cinco años. En una breve entrevista se obtuvieron perfiles de ejercicio físico en la infancia/adolescencia (PEFIA) y en los últimos cinco años. Estos perfiles se agruparon en tres categorías en función de la cantidad mínima de ejercicio recomendado para cada edad como: abajo, adecuada o arriba. La flexibilidad se evaluó mediante Flexitest y el flexindex (FLX) fue calculado mediante la adición de los resultados de la movilidad pasiva de cada uno de los 20 movimientos articulares medidos (escala de 0 a 4), que se ajustó posteriormente para la edad y el sexo en percentiles (P-FLX) (Araújo, 2008). Resultados: Hombres y mujeres adultos físicamente inactivos en los últimos cinco años tuvieron P-FLX medio, respectivamente, 25 y 35. Cuando se clasificaron por PEFIA, no hubo diferencias entre hombres (P = 0,23) y mujeres (P = 0,10) en P-FLX. Conclusión: La flexibilidad de adultos poco activos o sedentarios en los últimos cinco años, según FLX es menor de lo esperado para la edad y no está influenciada por el PEFIA, lo que indica que el reciente estilo de vida sedentario es perjudicial para la flexibilidad general y una historia de más ejercicio y/o deporte en la juventud no parece prevenir esta deficiencia.