92 research outputs found
Preliminary study of the effects of ultrasound on red wine polyphenols
The article evaluates the effect of high-power ultrasound (20 kHz) on the phenolic structure of red
wines, to study the possible applications of this innovative technique in wine aging. Different
treatment conditions, with times of 1, 3 and 5 minutes and amplitudes of 51, 102 and 153 \u3bcm,
were applied. In the experimental conditions the main parameters related to the evolution of red wine
phenolic compounds show interesting variations; in particular, we found significant differences on
tannins evaluated with some indices of tannins reactivity. On the other hand, free anthocyanins do
not undergo changes due to ultrasound application. The preliminary results, which definitely need a
depth, nonetheless allow us to hypothesize the application of ultrasound technology to accelerate the
aging of red wines, which normally requires (needs) long times in the cellar condition
High power ultrasound treatments of red young wines: Effect on anthocyanins and phenolic stability indices
Polyphenols, especially anthocyanins, play an important role on red wine sensory qualities and their evolution during storage. High Power Ultrasound (HPU) has been recognized as one of the most promising technologies which can be applied in winemaking processes for several purposes, and it is recently officially approved for crushed grapes treatments. The effect of ultrasound amplitude (41 and 81%) and treatment time (1, 3, and 5 min) has been studied on anthocyanins, flavan-3-ols, tannins, polymerized pigments, HCl index, and the color intensity of two finished red young wines. Anthocyanins and phenols compounds were not degraded with an increase in amplitude and sonication time, and the chromatic properties of the selected wines were preserved. Amplitude and ultrasound time were also evaluated considering their effect on evolution of anthocyanin content and phenolic stability indices during the first thirty days of storage. The higher level of amplitude (81%) induced a higher percentage decrease in tannins, 15% and 40% after 15 and 30 days of storage, respectively, compared to untreated wine which did not show a significant change during storage. HPU shows a possible chemical effect on the evolution of some analytical indices during bottling maturation, but their effectiveness could be strictly linked with the initial phenolic profile and ratios between polyphenol classes
Co-culture of Caco2 and HT-29 cells as an innovative method to mimic in vitro the morphology and permeability properties of human intestinal epithelium
For investigating the complexity of the human intestinal epithelium, a valid experimental approach is represented by co-culture. In the present study an intestinal co-culture Caco2/HT-29 (70/30) was set up starting from the parental populations of differentiated cells as previously described [1, 2]. Co-culture was harvested at 0 (T0), 6 (T6), and 14 (T14) days of post confluence after plating. Transmission electron microscopy was carried out to monitor the morphological features of cell differentiation. Alkaline Phosphatase (ALP), Aminopeptidase N (APN) and Dipeptidyl Peptidase IV (DPP IV) activity were assayed as known markers of intestinal cell differentiation. The measure of TEER and the apparent permeability of Lucifer Yellow allows to monitor the integrity of the tight junctions and the permeability of the cell layer formed. At T0 a classical monolayer is present, with a mixed population of immature absorptive elements and secretive cells. At T6 and T14, cells are progressively organized in a multilayer with a parallel growth of microvilli. At T6, co-culture demonstrates good properties of permeability and barrier components, such as mucus, representing an appropriate model for absorption study. At T14, the brush border is even more developed respect to T6 and, together with the increase of the specific activity of ALP, APN, and DPP IV, indicate co-culture as a good model for digestion study. The advantage of this co-culture described is the use of the whole cell population without particular inducers of subclones and growth supports. In conclusion, the morphological and biochemical features of co-cultured parental cells change with time, strongly supporting i) an active interaction between the two parental cell lines and ii) the versatility of this model, with more than one prevalent cell type depending on the post confluent stage
L-Carnitine Reduces Oxidative Stress and Promotes Cells Differentiation and Bone Matrix Proteins Expression in Human Osteoblast-Like Cells
Bone fragility and associated fracture risk are major problems in aging. Oxidative stress and mitochondrial dysfunction play a key role in the development of bone fragility. Mitochondrial dysfunction is closely associated with excessive production of reactive oxygen species (ROS). L-Carnitine (L-C), a fundamental cofactor in lipid metabolism, has an important antioxidant property. Several studies have shown how L-C enhances osteoblastic proliferation and activity. In the current study, we investigated the potential effects of L-C on mitochondrial activity, ROS production, and gene expression involved in osteoblastic differentiation using osteoblast-like cells (hOBs) derived from elderly patients. The effect of 5mM L-C treatment on mitochondrial activity and L-C antioxidant activity was studied by ROS production evaluation and cell-based antioxidant activity assay. The possible effects of L-C on hOBs differentiation were assessed by analyzing gene and protein expression by Real Time PCR and western blotting, respectively. L-C enhanced mitochondrial activity and improved antioxidant defense of hOBs. Furthermore, L-C increased the phosphorylation of Ca2+/calmodulin-dependent protein kinase II. Additionally, L-C induced the phosphorylation of ERK1/2 and AKT and the main kinases involved in osteoblastic differentiation and upregulated the expression of osteogenic related genes, RUNX2, osterix (OSX), bone sialoprotein (BSP), and osteopontin (OPN) as well as OPN protein synthesis, suggesting that L-C exerts a positive modulation of key osteogenic factors. In conclusion, L-C supplementation could represent a possible adjuvant in the treatment of bone fragility, counteracting oxidative phenomena and promoting bone quality maintenance
Betaine promotes cell differentiation of human osteoblasts in primary culture
BACKGROUND:
Betaine (BET), a component of many foods, is an essential osmolyte and a source of methyl groups; it also shows an antioxidant activity. Moreover, BET stimulates muscle differentiation via insulin like growth factor I (IGF-I). The processes of myogenesis and osteogenesis involve common mechanisms with skeletal muscle cells and osteoblasts sharing the same precursor. Therefore, we have hypothesized that BET might be effective on osteoblast cell differentiation.
METHODS:
The effect of BET was tested in human osteoblasts (hObs) derived from trabecular bone samples obtained from waste material of orthopedic surgery. Cells were treated with 10 mM BET at 5, 15, 60 min and 3, 6 and 24 h. The possible effects of BET on hObs differentiation were evaluated by real time PCR, western blot and immunofluorescence analysis. Calcium imaging was used to monitor intracellular calcium changes.
RESULTS:
Real time PCR results showed that BET stimulated significantly the expression of RUNX2, osterix, bone sialoprotein and osteopontin. Western blot and immunofluorescence confirmed BET stimulation of osteopontin protein synthesis. BET stimulated ERK signaling, key pathway involved in osteoblastogenesis and calcium signaling. BET induced a rise of intracellular calcium by means of the calcium ions influx from the extracellular milieu through the L-type calcium channels and CaMKII signaling activation. A significant rise in IGF-I mRNA at 3 and 6 h and a significant increase of IGF-I protein at 6 and 24 h after BET stimulus was detected. Furthermore, BET was able to increase significantly both SOD2 gene expression and protein content.
CONCLUSIONS:
Our study showed that three signaling pathways, i.e. cytosolic calcium influx, ERK activation and IGF-I production, are enhanced by BET in human osteoblasts. These pathways could have synergistic effects on osteogenic gene expression and protein synthesis, thus potentially leading to enhanced bone formation. Taken together, these results suggest that BET could be a promising nutraceutical therapeutic agent in the strategy to counteract the concomitant and interacting impact of sarcopenia and osteoporosis, i.e. the major determinants of senile frailty and related mortality
Discursos e a construção do senso comum sobre alimentação a partir de uma revista feminina
Diversos elementos contribuem para a construção do senso comum sobre alimentação com impacto na saúde das populações. Nesse estudo, parte-se da hipótese de que o discurso midiático desempenha um papel estruturador relevante no processo de construção e consolidação de padrões de estética corporal e de alimentação, produzindo sentidos coletivos que interferem nas escolhas feitas pelos sujeitos. Este trabalho objetivou reconhecer as estratégias discursivas adotadas por um veículo midiático direcionado ao público feminino quanto à alimentação saudável e sua contribuição para a formação do senso comum sobre o tema. Foram analisadas as matérias de capa dos doze números de uma revista feminina publicados no ano de 2007, segundo o referencial teórico da análise do discurso. Foi observado um discurso carregado de ambiguidade entre beleza e saúde, com forte apelo à sensualidade e ao culto do corpo perfeito, predominantemente divergente do saber científico na área da nutrição, legitimado por dois outros discursos transversais, o socioestético e o especializado. Concluiu-se que as estratégias discursivas adotadas pelo veículo midiático analisado contribuem para a formação de um saber comum sobre práticas alimentares que é frágil e não habilita os sujeitos para escolhas autônomas e saudáveis.Several factors contribute to the construction of common sense on food with impact on public health. In this study, our hypothesis was that media discourse plays an important structuring role in the process of body aesthetics and food patterns construction and consolidation, producing collective senses that interfere in the choices made by people. The study aimed to recognize the discursive strategies adopted by a media vehicle targeted at women about healthy eating, and their contribution to the formation of common sense on the subject. We analyzed the twelve cover reports of a women's magazine published in 2007, according to the theoretical framework of discourse analysis. A discourse full of ambiguity between beauty and health was observed, with a strong appeal to sensuality and to the cult of the perfect body, predominantly divergent from scientific knowledge in the nutrition area, legitimized by two other cross discourses, the socioaesthetic and the specialized ones. We conclude that the discursive strategies adopted by the media vehicle that was examined contribute to the formation of a common knowledge about eating habits that is fragile and does not enable people to make independent and healthy choices
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