CD1 is involved in diet-induced hypothalamic inflammation in obesity.

Obesity-associated hypothalamic inflammation plays an important role in the development of defective neuronal control of whole body energy balance. Because dietary fats are the main triggers of hypothalamic inflammation, we hypothesized that CD1, a lipid-presenting protein, may be involved in the hypothalamic inflammatory response in obesity. Here, we show that early after the introduction of a high-fat diet, CD1 expressing cells gradually appear in the mediobasal hypothalamus. The inhibition of hypothalamic CD1 reduces diet-induced hypothalamic inflammation and rescues the obese and glucose-intolerance phenotype of mice fed a high-fat diet. Conversely, the chemical activation of hypothalamic CD1 further increases diet-induced obesity and hypothalamic inflammation. A bioinformatics analysis revealed that hypothalamic CD1 correlates with transcripts encoding for proteins known to be involved in diet-induced hypothalamic abnormalities in obesity. Thus, CD1 is involved in at least part of the hypothalamic inflammatory response in diet-induced obesity and its modulation affects the body mass phenotype of mice.

Development and Function of the Blood-Brain Barrier in the Context of Metabolic Control.

Under physiological conditions, the brain consumes over 20% of the whole body energy supply. The blood-brain barrier (BBB) allows dynamic interactions between blood capillaries and the neuronal network in order to provide an adequate control of molecules that are transported in and out of the brain. Alterations in the BBB structure and function affecting brain accessibility to nutrients and exit of toxins are found in a number of diseases, which in turn may disturb brain function and nutrient signaling. In this review we explore the major advances obtained in the understanding of the BBB development and how its structure impacts on function. Furthermore, we focus on the particularities of the barrier permeability in the hypothalamus, its role in metabolic control and the potential impact of hypothalamic BBB abnormities in metabolic related diseases.

Avaliação in vitro da atividade fotoprotetora de extratos vegetais do cerrado de Mato Grosso / In vitro sunscreen activity evaluation of plants Iextracts from Mato Grosso cerrado

O cerrado brasileiro é um bioma detentor de grande diversidade biológica. No entanto, são escassas as pesquisas de espécies vegetais, especialmente do cerrado mato-grossense, com potencial para serem utilizadas como filtros solares naturais. O objetivo desta pesquisa foi estudar o potencial fotoprotetor de espécies de diferentes famílias (Apocynaceae, Lythraceae, Oxalidaceae) do cerrado da região do Rio Manso, Chapada dos Guimarães - MT. A absorbância dos extratos etanólicos secos foram medidas em diferentes concentrações entre os comprimentos de onda de 260 a 400nm para verificar a absorção nas regiões ultravioleta A e B (UVA e UVB). As plantas que apresentaram absorbância na região estudada foram submetidas a uma análise fitoquímica qualitativa preliminar para determinar a presença de polifenóis e alcalóides, constituintes característicos de plantas que absorvem a radiação UV. Os extratos etanólicos secos que apresentaram absorção em UVB foram submetidos ao teste de determinação in vitro do Fator de Proteção Solar (FPS) desenvolvido por Mansur. M. Velame apresentou absorção na região UVB com absorbância máxima em 318nm, enquanto que a L. pacari e O. hirsutissima apresentaram absorbância na região UVA. Na concentração utilizada e padronizada, nenhuma das espécies apresentou FPS >2, sendo assim não podem ser consideradas plantas com potencial fotoprotetor.

The Brazilian savanna is a holding biome of large biological diversity. However, the researches of plants species are scarce, especially at the Mato Grosso's savanna; which have potential to be used as natural sunscreen. The objective of this research was to study the photoprotector potential of several species (Apocynaceae, Lythraceae, Oxalidaceae) from the savanna's region at the Manso River, Chapada dos Guimarães - MT. The absorbance of dry ethanolic extracts were measured in different concentrations, between waves from 260nm until 400 nm in length. Just to check the absorption in the A and B ultraviolet regions (UVA and UVB). The plants that presented absorbance by the studied area were submitted to a preliminary qualitative phytochemical analysis to determine if there are polyphenols and alkaloids inside, because they are typical constituents of plants that absorber the UV radiation. The dry ethanolic extracts, that presented absorption in UVB, were submitted to a in vitro Sun Protection Factor (SPF) determination test, developed by Mansur. M.velame presented absorption in the UVB region with maximal absorbance at 318 nm, while L. pacari and O. hirsutissima presented absorbance in the UVA region. At the used and standardized concentration, no species presented SPF > 2, so they cannot be considered plants with photoprotector potential.