Nuclear receptors in vascular biology

Nuclear receptors sense a wide range of steroids and hormones (estrogens, progesterone, androgens, glucocorticoid, and mineralocorticoid), vitamins (A and D), lipid metabolites, carbohydrates, and xenobiotics. In response to these diverse but critically important mediators, nuclear receptors regulate the homeostatic control of lipids, carbohydrate, cholesterol, and xenobiotic drug metabolism, inflammation, cell differentiation and development, including vascular development. The nuclear receptor family is one of the most important groups of signaling molecules in the body and as such represent some of the most important established and emerging clinical and therapeutic targets. This review will highlight some of the recent trends in nuclear receptor biology related to vascular biology

Association between actual weight status, perceived weight and depressive, anxious symptoms in Chinese adolescents: a cross-sectional study

<p>Abstract</p> <p>Backgroud</p> <p>The purpose of this study was to describe actual measured weight and perceived weight and to explore associations with depressive, anxiety symptoms in school adolescents in China.</p> <p>Methods</p> <p>A sample of 1144 Chinese adolescents was randomly selected from four schools in Wuhan, China, including 665 boys and 479 girls with ages ranging between 10 and 17 years. Actual measured weight and height and perceived weight status were compared to anxiety and depressive symptoms measured using the revised Self-Rating Anxiety Scale and Children's Depression Inventory. A general linear model was used to compare differences in psychological symptoms among the teenagers with different measured and perceived weights.</p> <p>Results</p> <p>When compared with standardized weight tables (WHO age- and gender-specific body mass index (BMI) cutoffs (2007 reference)), girls were more likely to misperceive themselves as overweight, whereas more boys misclassified their weight status as underweight. The adolescents who perceived themselves as overweight were more likely to experience depressive and anxiety symptoms (except girls) than those who perceived themselves as normal and/or underweight. However, no significant association was found between depressive and anxiety symptoms actual measured weight status.</p> <p>Conclusions</p> <p>Perceived weight status, but not the actual weight status, was associated with psychological symptoms.</p

P2 receptors are involved in the mediation of motivation-related behavior

The importance of purinergic signaling in the intact mesolimbic–mesocortical circuit of the brain of freely moving rats is reviewed. In the rat, an endogenous ADP/ATPergic tone reinforces the release of dopamine from the axon terminals in the nucleus accumbens as well as from the somatodendritic region of these neurons in the ventral tegmental area, as well as the release of glutamate, probably via P2Y1 receptor stimulation. Similar mechanisms may regulate the release of glutamate in both areas of the brain. Dopamine and glutamate determine in concert the activity of the accumbal GABAergic, medium-size spiny neurons thought to act as an interface between the limbic cortex and the extrapyramidal motor system. These neurons project to the pallidal and mesencephalic areas, thereby mediating the behavioral reaction of the animal in response to a motivation-related stimulus. There is evidence that extracellular ADP/ATP promotes goal-directed behavior, e.g., intention and feeding, via dopamine, probably via P2Y1 receptor stimulation. Accumbal P2 receptor-mediated glutamatergic mechanisms seem to counteract the dopaminergic effects on behavior. Furthermore, adaptive changes of motivation-related behavior, e.g., by chronic succession of starvation and feeding or by repeated amphetamine administration, are accompanied by changes in the expression of the P2Y1 receptor, thought to modulate the sensitivity of the animal to respond to certain stimuli

Effort-related functions of nucleus accumbens dopamine and associated forebrain circuits

Background Over the last several years, it has become apparent that there are critical problems with the hypothesis that brain dopamine (DA) systems, particularly in the nucleus accumbens, directly mediate the rewarding or primary motivational characteristics of natural stimuli such as food. Hypotheses related to DA function are undergoing a substantial restructuring, such that the classic emphasis on hedonia and primary reward is giving way to diverse lines of research that focus on aspects of instrumental learning, reward prediction, incentive motivation, and behavioral activation. Objective The present review discusses dopaminergic involvement in behavioral activation and, in particular, emphasizes the effort-related functions of nucleus accumbens DA and associated forebrain circuitry. Results The effects of accumbens DA depletions on food-seeking behavior are critically dependent upon the work requirements of the task. Lever pressing schedules that have minimal work requirements are largely unaffected by accumbens DA depletions, whereas reinforcement schedules that have high work (e.g., ratio) requirements are substantially impaired by accumbens DA depletions. Moreover, interference with accumbens DA transmission exerts a powerful influence over effort-related decision making. Rats with accumbens DA depletions reallocate their instrumental behavior away from food-reinforced tasks that have high response requirements, and instead, these rats select a less-effortful type of food-seeking behavior. Conclusions Along with prefrontal cortex and the amygdala, nucleus accumbens is a component of the brain circuitry regulating effort-related functions. Studies of the brain systems regulating effort-based processes may have implications for understanding drug abuse, as well as energy-related disorders such as psychomotor slowing, fatigue, or anergia in depression

Atitudes de nutricionistas em relação a indivíduos obesos – um estudo exploratório

The scope of this study was to assess attitudes of dietitians in relation to obesity; involving beliefs about the characteristics attributed to obese people, the reasons that lead to obesity and obesity itself. Dietitians (N = 344; 97.1% women) were contacted via their professional council and filled out the online survey. The survey questions were translated and adapted from international studies on this subject and the responses were analyzed for concordance rate. The results pointed to strong stigmatization of obesity and prejudice against the obese, attributing characteristics such as greed (67.4%), unattractiveness (52.0%), ungainliness (55.1%), lack of willpower (43.6%) and laziness (42.3%). The most important causal factors were considered to be emotional and mood changes, food addiction and low self-esteem. Research on this topic should be enhanced since these attitudes can affect the efficacy of treatment and also to foster broad discussion and training regarding the significance of obesity and to ensure more individualized and humanized treatment for obese patients.O objetivo foi identificar atitudes de nutricionistas em relação à obesidade; envolvendo crenças sobre características atribuídas às pessoas obesas, fatores de desenvolvimento e a obesidade em si. Os participantes (N = 344; 97,1% mulheres) foram contatados via conselho profissional e responderam a pesquisa online. As questões do estudo foram adaptadas de trabalhos internacionais com as respostas analisadas por frequência de concordância. As respostas indicaram forte estigmatização da obesidade e preconceito contra o obeso, atribuindo características como: guloso (67,4%), não atraente (52,0%), desajeitado (55,1%), sem determinação (43,6%) e preguiçoso (42,3%). E considerando entre os mais importantes fatores causais: alterações emocionais e de humor, vício ou dependência de comida e baixa autoestima. Esta temática deve ser mais pesquisada uma vez que tais atitudes podem impactar a eficácia do tratamento; também para discussão e formação ampla sobre os significados da obesidade, e tratamento mais individualizado e humanizado para pacientes obesos.Universidade de São Paulo Faculdade de Saúde PúblicaUniversidade Federal de São Paulo (UNIFESP) Faculdade de NutriçãoUNIFESP, Faculdade de NutriçãoSciEL