Digestion-resistant whey peptides promote antioxidant effect on Caco-2 cells.

Enteric endothelial cells are the first structure to come in contact with digested food and may suffer oxidative damage by innumerous exogenous factors. Although peptides derived from whey digestion have presented antioxidant potential, little is known regarding antioxidant pathways activation in Caco-2 cell line model. Hence, we evaluated the ability to form whey peptides resistant to simulated gastrointestinal digestive processes, with potential antioxidant activity on gastrointestinal cells and associated with sequence structure and activity. Using the INFOGEST method of simulated static digestion, we achieved 35.2% proteolysis, with formation of peptides of low molecular mass (<600 Da) evaluated by FPLC. The digestion-resistant peptides showed a high proportion of hydrophobic and acidic amino acids, but with average surface hydrophobicity. We identified 24 peptide sequences, mainly originated from ß-lactoglobulin, that exhibit various bioactivities. Structurally, the sequenced peptides predominantly contained the amino acids lysine and valine in the N-terminal region, and tyrosine in the C-terminal region, which are known to exhibit antioxidant properties. The antioxidant activity of the peptide digests was on average twice as potent as that of the protein isolates for the same concentration, as evaluated by ABTS, DPPH and ORAC. Evaluation of biological activity in Caco-2 intestinal cells, stimulated with hydrogen peroxide, showed that they attenuated the production of reactive oxygen species and prevented GSH reduction and SOD activity increase. Caco-2 cells were not responsive to nitric oxide secretion. This study suggests that whey peptides formed during gastric digestion exhibit biological antioxidant activity, without the need for previously hydrolysis with exogenous enzymes for supplement application. The study's primary contribution was demonstrating the antioxidant activity of whey peptides in maintaining the gastrointestinal epithelial cells, potentially preventing oxidative stress that affects the digestive system.

In vitro inhibition of glucose gastro-intestinal enzymes and antioxidant activity of hydrolyzed collagen peptides from different species.

The growing value of industrial collagen by-products has given rise to interest in extracting them from different species of animals. Intrinsic protein structure variation of collagen sources and its hydrolysis can bring about different bioactivities. This study aimed to characterize and evaluate the differences in vitro biological potential of commercial bovine (BH), fish (FH), and porcine hydrolysates (PH) regarding their antioxidant and hypoglycemic activities. All samples showed percentages above 90% of protein content, with high levels of amino acids (glycine, proline, and hydroxyproline), responsible for the specific structure of collagen. The BH sample showed a higher degree of hydrolysis (DH) (8.7%) and a higher percentage of smaller than 2 kDa peptides (74.1%). All collagens analyzed in vitro showed inhibition of pancreatic enzymes (α-amylase and α-glucosidase), with the potential to prevent diabetes mellitus. The PH sample showed higher antioxidant activities measured by ORAC (67.08 ± 4.23 µmol Trolox Eq./g) and ABTS radical scavenging (65.69 ± 3.53 µmol Trolox Eq./g) methods. For the first time, DNA protection was analyzed to hydrolyzed collagen peptides, and the FH sample showed a protective antioxidant action to supercoiled DNA both in the presence (39.51%) and in the absence (96.36%) of AAPH (reagent 2,2'-azobis(2-amidinopropane)). The results confirmed that the source of native collagen reflects on the bioactivity of hydrolyzed collagen peptides, probably due to its amino acid composition. PRACTICAL APPLICATIONS: Our data provide new application for collagen hydrolysates with hypoglycemiant and antioxidant activity. These data open discussion for future studies on the additional benefits arising from collagen peptide consumption for the prevention of aging complications or hyperglycemic conditions as observed in chronic diseases such as diabetes mellitus type II (DM 2). The confirmation of these results can open new market areas for the use of collagen with pharmacological applications or to produce new supplements. Furthermore, provides a solution for waste collagen from meat industries and adds value to the product.

Impact of Gluten-Free Sorghum Bread Genotypes on Glycemic and Antioxidant Responses in Healthy Adults.

Sorghum is used to provide good quality gluten-free products due to phytochemicals and low glycemic index (GI). This study aimed to determine the chemical composition, the antioxidant activity and capacity, and the glycemic and insulinemic responses of gluten-free (GF) sorghum bread. GF bread samples were produced with three different sorghum genotypes. The samples were analyzed for chemical composition, resistant starch and dietary fiber content; antioxidant activity by ORAC; antioxidant capacity by FRAP; GI; and insulinemic responses. This double-blind, crossover, randomized clinical trial was conducted with 10 healthy men aged 28.0 ± 4.9 years (77.6 ± 11.7 kg and 24.2 ± 2.3 kg/m2). All sorghum bread showed significantly more fiber than rice bread (control). Brown sorghum bread was classified as low GI, bronze and white as medium GI, and control as high GI. Brown sorghum bread presented a low carbohydrate content, a significant amount of fiber, and a significantly lower 3 h AUC glucose response than those of the control, aside from the highest antioxidant activity value (p ≤ 0.001). Therefore, brown sorghum was superior to other genotypes analyzed in this study, and its production should be encouraged to provide gluten-free products with a better nutritional profile. More research is required to explore the effects of different sorghum genotypes in food products on human health.

Amorphophallus konjac: A Novel Alternative Flour on Gluten-Free Bread.

The demand for gluten-free products is rising, but their production with similar quality as their gluten counterparts is challenging. This study aimed to develop gluten-free bread samples using different concentrations of Amorphophallus konjac flour (0%, 12.5%, 25%, 37.5%, and 50% of the total flour content) and to evaluate their nutritional and physicochemical properties. Proteins, lipids, carbohydrates, moisture, ash content, fibers, resistant starch, firmness, specific volume, and color were evaluated using official methods. Protein varied from 2.95% to 4.94%, the energy value from 347.93 to 133.55 kcal/100 g, dietary fiber from 8.19 to 17.90%, and resistant starch from 0.67% to 0.75% on wet basis. The addition of konjac flour positively influenced the specific volume. Higher concentrations of konjac flour in the formulations led to lower calories of the bread due to the significant addition of water to the dough. The bread samples with konjac showed high fiber content due to the composition of the flour. They had lower levels of carbohydrates, which can positively influence the glycemic index. Konjac flour provided dough mold, growth, and better texture for gluten-free bread. The best formulations were prepared in concentrations up to 37.5% konjac. The 50% konjac bread showed slightly reduced specific volume and pale color.

Chemical Composition and Glycemic Index of Gluten-Free Bread Commercialized in Brazil.

Nowadays, the world is experiencing an increased demand for gluten-free products associated with the high prevalence of gluten-related disorders (GRD). As this market thrives, bread stands out as the most demanded and consumed product, highlighting the need to evaluate its nutritional quality. In this sense, this cross-sectional study aimed to assess the ingredients, chemical composition, and glycemic index of gluten-free bread (GFB) commercialized nationwide in Brazil. The labels were analyzed according to their ingredients and composition. In addition, centesimal composition analysis (moisture, carbohydrates, protein, ash, lipid, and fiber) was performed using the official methods, as well as the in vivo glycemic index. Significant differences between manufacturing lots of each brand and between different gluten-free bread samples were found. There is a mismatch from what is stipulated by the Brazilian legislation between analytical data and the data described on sample labels. Samples showed predominantly refined starch and high glycemic index profile. Most samples (75%, n = 6) of the non-whole gluten-free bread (n = 8) presented high glycemic index (GI). From four whole food/multigrain gluten-free bread samples, three of them (75%) presented medium GI. However, two samples presented GI near the value to be considered high. The results suggest a lack of production control, impairing the gluten-free nutritional label as a reliable information source and tool for dietary control. Therefore, it is necessary to standardize the process of gluten-free bread production and labeling, as well as to improve the nutritional characteristics of these products, aiming the give accurate information to consumers and provide a healthier product beyond the sensory characteristics.

Roasting soybeans in a microwave for manufacturing chocolate dragées / Torração de soja em micro-ondas para desenvolvimento de drágeas de chocolate

ABSTRACT: This study aimed to evaluate the effect of different microwave-roasting timeson different sizes of soybean grains with black tegument to achieve the best crunchiness, flavor, and hardness. Black soybean dragées- containing a soybean core coated with layers of chocolate (dragée) - were manufactured, and their nutritional value, microbiological risk, acceptability, and consumer-purchase intentions were verified. Flavor and crunchiness of the roasted black soybeans wereonly affected by the roasting time in the microwave, whereas the hardness was only affected by grain size. The best core of the dragéewas obtainedusing grains ofsieve size 15 (large grains) roastedin the microwave for 11 min; this core presented higher frequencies for extremely crunchy notes (56%), toasted flavor (61%), and an instrumental hardness close to that of the existing commercial product (33.17 N). The manufactured dragées did not present resistant starch, anthocyanins, and microbiological risk, and they were sensorially accepted by the tasters (mean scores of 7.77 for texture and 8.36 for appearance on a scale of 1 to 9). Thus, roasted black soybean dragéeshave a high marketing potential from technological, nutritional, and sensorial points of view.

RESUMO: Este estudo objetivou avaliar o efeito do tempo de torra no micro-ondas para diferentes tamanhos de grãos de soja tipo alimento de tegumento preto, de forma a atingir a melhor crocância, sabor e dureza, e em seguida caracterizar o seu confeito, estruturado na forma de núcleo e camadas de cobertura de chocolate (drageados), em relação ao valor nutricional, risco microbiológico, aceitabilidade e intenção de compra pelos consumidores. O sabor e a crocância da soja preta torrada foram afetados somente pelo tempo de torra em micro-ondas, enquanto a dureza somente foi afetada pela dimensão dos grãos. O melhor núcleo (selecionado) foi obtido com os grãos de peneira 15 (grãos grandes), no tempo de 11 min de torra em micro-ondas, pois apresentou maior frequência para as notas de extremamente crocante (56%), sabor de torrado (61%), e uma dureza instrumental próxima ao produto comercial (33,17 N). As drágeas não apresentaram amido resistente, antocianinas e risco microbiológico, e foram sensorialmente aceitas pelos provadores (scores médios de 7,77 para textura e 8,36 para aparência, em uma escala de 1 a 9). Portanto, o drageado de soja preta torrada com chocolate é viável do ponto de vista tecnológico, nutricional e sensorial, com alto potencial de comercialização.

Cataracts and strabismus associated with hand rearing using artificial milk formulas in Bengal tiger (Panthera tigris spp tigris) cubs.

The aim of this investigation is to describe the potential contributing nutritional factors involved in the development of ophthalmic and dermatologic changes in four Bengal tiger (Panthera tigris spp tigris) cubs fed an artificial milk formula. The affected animals were compared with two other tiger cubs that had been nursed by their dam naturally. After the first clinical signs appeared, the tiger cubs underwent ophthalmic evaluation. Severe symmetric generalized alopecia over the trunk, sparing the head and distal portion of the front and rear limbs, bilateral cataracts and strabismus were noticed. Milk and blood from the mother, as well as blood from the healthy and affected cubs were collected in order to evaluate complete blood counts, serum chemistry values, and amino acid levels. The amino acid concentrations in the artificial formula were also evaluated for comparison to the milk from the dam. The concentration of taurine, arginine, phenylalanine, tryptophan and histidine were very low in the artificial formulas as compared to the dam´s milk. The tiger cubs that received the artificial formula had lower levels of the amino acids listed previously as compared to those that nursed from the dam naturally. Taurine, as well as arginine, phenylalanine, tryptophan and histidine deficiency appeared to be possible causes of the development of skin problems, cataracts and strabismus in the tiger cubs fed with these particular artificial milk replacers. In the future, special attention should be given in order to make sure that adequate levels of these amino acids are present in artificial milk for tiger cubs.

Novel protein interactions with endoglin and activin receptor-like kinase 1: potential role in vascular networks.

Endoglin and activin receptor-like kinase 1 are specialized transforming growth factor-beta (TGF-ß) superfamily receptors, primarily expressed in endothelial cells. Mutations in the corresponding ENG or ACVRL1 genes lead to hereditary hemorrhagic telangiectasia (HHT1 and HHT2 respectively). To discover proteins interacting with endoglin, ACVRL1 and TGF-ß receptor type 2 and involved in TGF-ß signaling, we applied LUMIER, a high-throughput mammalian interactome mapping technology. Using stringent criteria, we identified 181 novel unique and shared interactions with ACVRL1, TGF-ß receptor type 2, and endoglin, defining potential novel important vascular networks. In particular, the regulatory subunit B-beta of the protein phosphatase PP2A (PPP2R2B) interacted with all three receptors. Interestingly, the PPP2R2B gene lies in an interval in linkage disequilibrium with HHT3, for which the gene remains unidentified. We show that PPP2R2B protein interacts with the ACVRL1/TGFBR2/endoglin complex and recruits PP2A to nitric oxide synthase 3 (NOS3). Endoglin overexpression in endothelial cells inhibits the association of PPP2R2B with NOS3, whereas endoglin-deficient cells show enhanced PP2A-NOS3 interaction and lower levels of endogenous NOS3 Serine 1177 phosphorylation. Our data suggest that endoglin regulates NOS3 activation status by regulating PPP2R2B access to NOS3, and that PPP2R2B might be the HHT3 gene. Furthermore, endoglin and ACVRL1 contribute to several novel networks, including TGF-ß dependent and independent ones, critical for vascular function and potentially defective in HHT.

Development of low-calorie guava preserves with prebiotics and evaluation of their effects on carcinogenesis biomarkers in rats.

Faced with the search for healthy products that provide additional benefits to consumers' health, the main objectives of this work were to develop a low-calorie preserve containing prebiotics (lactulose and polydextrose) and to evaluate the effects of these prebiotics on oxidative stress and colon carcinogenesis in male rats treated with 1,2-dimethylhydrazine (DMH). A total of 62.5% w/w of the sucrose in conventional preserves was replaced by polydextrose, and lactulose was added at 0%, 16%, 19.5% or 23% w/w concentrations. The acceptance of these four low-calorie guava preserve samples and the conventional sample was equal (P>0.05), with a score of 6.49. The level of degradation of lactulose was low (18.45 g100 g(-1)lactulose), ensuring that even at a lower concentration of this prebiotic (16% w/w), the concentration remained above the minimum level considered functional. We found that consumption of the low-calorie preserves with prebiotics does not have an effect on the development of mucin-negative ACF and classical ACF in the initiation phase of the mutagenic process. However, the consumption of 1.5 g of the preserve/rat/day potentiated lipid peroxidation and proteic oxidation in the liver.

Gênero e os sentidos do trabalho social / Gender and the meanings of social work

A partir de pesquisa realizada com profissionais do Programa de Inclusão Social (PIS), do Estado Mato Grosso do Sul, gestão 2003-2006, este artigo discute os sentidos do trabalho social, ressaltando sentidos da relação gênero e trabalho e da naturalização da participação da mulher no trabalho social. A pesquisa pautou-se por aportes da Psicologia Social, em diálogo com teorias de gênero e literatura sobre trabalho social. Apresentamos cinco conjuntos de sentidos do trabalho social, a saber: ajuda; promoção de direitos e transformação social; mercado profissional e gestão social; estratégia político-eleitoral e assistencialista. O quinto conjunto agrega sentidos das relações de gênero e incluem o afeto como instrumento de trabalho, o desapego financeiro e o não-profissionalismo. Apesar de positividades, esses sentidos alimentam a desvalorização, a invisibilidade e a feminização dessa atividade.(AU)

Based upon a research done with professionals of the Program for Social Inclusion (PIS), of Mato Grosso do Sul, Brazil, during 2003-2006, the article discusses the meanings of social work, highlighting meanings of gender and work relationship and the naturalization of women's participation in the territory of social work. The research was developed under the perspective of Social Psychology, including dialogues with theories of gender and literature on social work. We present five sets of meanings assigned to this activity: social work as an aid, as an element of social change and rights promotion, as a professional category and social management, as a vote-seeking and aid-oriented strategy. The fifth set includes meanings produced within gender relationships such as: kindness as a work tool, lack of financial attachment and lack of professional skills. Although the positive aspects of this net, it also feeds a process of devaluation, invisibility and feminization of the social work.(AU)

Gênero e os sentidos do trabalho social / Gender and the meanings of social work

A partir de pesquisa realizada com profissionais do Programa de Inclusão Social (PIS), do Estado Mato Grosso do Sul, gestão 2003-2006, este artigo discute os sentidos do trabalho social, ressaltando sentidos da relação gênero e trabalho e da naturalização da participação da mulher no trabalho social. A pesquisa pautou-se por aportes da Psicologia Social, em diálogo com teorias de gênero e literatura sobre trabalho social. Apresentamos cinco conjuntos de sentidos do trabalho social, a saber: ajuda; promoção de direitos e transformação social; mercado profissional e gestão social; estratégia político-eleitoral e assistencialista. O quinto conjunto agrega sentidos das relações de gênero e incluem o afeto como instrumento de trabalho, o desapego financeiro e o não-profissionalismo. Apesar de positividades, esses sentidos alimentam a desvalorização, a invisibilidade e a feminização dessa atividade.

Based upon a research done with professionals of the Program for Social Inclusion (PIS), of Mato Grosso do Sul, Brazil, during 2003-2006, the article discusses the meanings of social work, highlighting meanings of gender and work relationship and the naturalization of women's participation in the territory of social work. The research was developed under the perspective of Social Psychology, including dialogues with theories of gender and literature on social work. We present five sets of meanings assigned to this activity: social work as an aid, as an element of social change and rights promotion, as a professional category and social management, as a vote-seeking and aid-oriented strategy. The fifth set includes meanings produced within gender relationships such as: kindness as a work tool, lack of financial attachment and lack of professional skills. Although the positive aspects of this net, it also feeds a process of devaluation, invisibility and feminization of the social work.

Crise dos serviços de saúde no cotidiano da mídia impressa / The news about the health service crisis in the newspaper

Apoiando-nos na perspectiva da Psicologia Social, acatamos o pressuposto de que a mídia é um importante espaço de difusão de informações, atuando como co-produtora de sentidos e de subjetividades no cotidiano das pessoas. Assim, a partir da análise de notícias, publicadas em jornais de Campo Grande, MS, tendo como tema serviços de saúde e, mais especificamente, notícias sobre um período de crise nesses serviços, problematizamos o posicionamento do hospital como lócus privilegiado no cuidado com a saúde e as formas verticais de negociação. A ruptura com essa associação e a abertura ao diálogo é um grande desafio para que o Sistema Único de Saúde (SUS) se constitua em um sistema público, pautado pelos eixos da integralidade e da humanização na atenção à saúde que, no debate atual, formatam propostas defendidas pela Saúde Coletiva e outras áreas que atuam na saúde, entre eles a Psicologia.(AU)

From the perspective of Social Psychology, we agree on the assumption that news media is an important space to propagate information, acting as a co-producer of meanings and of subjectivities in people's everyday lives. Therefore, based on the analysis of newspaper news, published in local newspapers of Campo Grande , MS, and having as their subject health service, more specifically news about the crisis in this kind of service, we critically consider the positioning of hospitals as the privileged locus for health care as well as the vertical forms of negotiation. The rupture with this association and the opening for dialogue conveys a great challenge for the Sistema Única de Sáude - SUS (Brazil's public health care system) so that it can be constituted as a public system, based on universal health care and humanization of health care attention which, under current debate, forms the proposals defended by Collective Health and other fields of knowledge involved in health care, including Psychology.(AU)

Crise dos serviços de saúde no cotidiano da mídia impressa / The news about the health service crisis in the newspaper

Apoiando-nos na perspectiva da Psicologia Social, acatamos o pressuposto de que a mídia é um importante espaço de difusão de informações, atuando como co-produtora de sentidos e de subjetividades no cotidiano das pessoas. Assim, a partir da análise de notícias, publicadas em jornais de Campo Grande, MS, tendo como tema serviços de saúde e, mais especificamente, notícias sobre um período de crise nesses serviços, problematizamos o posicionamento do hospital como lócus privilegiado no cuidado com a saúde e as formas verticais de negociação. A ruptura com essa associação e a abertura ao diálogo é um grande desafio para que o Sistema Único de Saúde (SUS) se constitua em um sistema público, pautado pelos eixos da integralidade e da humanização na atenção à saúde que, no debate atual, formatam propostas defendidas pela Saúde Coletiva e outras áreas que atuam na saúde, entre eles a Psicologia.

From the perspective of Social Psychology, we agree on the assumption that news media is an important space to propagate information, acting as a co-producer of meanings and of subjectivities in people's everyday lives. Therefore, based on the analysis of newspaper news, published in local newspapers of Campo Grande , MS, and having as their subject health service, more specifically news about the crisis in this kind of service, we critically consider the positioning of hospitals as the privileged locus for health care as well as the vertical forms of negotiation. The rupture with this association and the opening for dialogue conveys a great challenge for the Sistema Única de Sáude - SUS (Brazil's public health care system) so that it can be constituted as a public system, based on universal health care and humanization of health care attention which, under current debate, forms the proposals defended by Collective Health and other fields of knowledge involved in health care, including Psychology.

Documentos de domínio público como produtos e autores sociais / Documents of public domain as social products and social authors

Considerando os documentos de domínio público como práticas discursivas, este artigo discute a importância que esses documentos têm na formatação de estratégias de governamentalidade. Essa argumentação é fundamentada por duas pesquisas realizadas pelos autores. A primeira discute linguagem na perspectiva pragmática de Levinson, articulando o conceito de interanimação dialógica de Bakhtin. Como exemplo utiliza-se a análise de documentos que expõem o debate da formação em Psicologia no Brasil, discutindo-sepermanências, rupturas e cooptações das políticas públicas educacionais. A análise da segunda pesquisa foca as linguagens sociais, na perspectiva de Bakhtin, articulando a noção de governamentalidade de Foucault e o argumento de Rose, para quem a linguagem é constitutiva de estratégias de governamentalidade.O exemplo vem da análise de documentos de consentimento informado para reprodução humana assistida, que mostra a ambigüidade da linguagem dos riscos e dos direitos, explicitando ser a prática social do consentimento uma estratégia de governamentalidade(AU)

Considering the documents of public domain as discursive practices, this article discusses the importance ofsuch documents in establishing governmentality strategies. The given arguments are based upon tworesearches done by the authors. The first one discusses the language in accordance with Levinson’s pragmaticperspective, and articulates Bakhtin’s concept of dialogic interanimation. The example is extracted from the analysis of some documents that give visibility to the debate about the psychological formation in Brazil, discussing constancies, ruptures, and co-optations of the educational public politics. The second research analysis focuses on the use of social language, as proposed by Bakhtin, articulating Foucault’sgovernamentality notion and Rose’s argument that language is constitutive of governmentality strategies. Inthis case, the analysis of the written informed consent for assisted human reproduction shows the ambiguityof the language of risks and the language of rights, positioning the social practice of the informed consent asa governmentality strategy(AU)

Endoglin null endothelial cells proliferate faster and are more responsive to transforming growth factor beta1 with higher affinity receptors and an activated Alk1 pathway.

Endoglin is an accessory receptor for transforming growth factor beta (TGFbeta) in endothelial cells, essential for vascular development. Its pivotal role in angiogenesis is underscored in Endoglin null (Eng-/-) murine embryos, which die at mid-gestation (E10.5) from impaired yolk sac vessel formation. Moreover, mutations in endoglin and the endothelial-specific TGFbeta type I receptor, ALK1, are linked to hereditary hemorrhagic telangiectasia. To determine the role of endoglin in TGFbeta pathways, we derived murine endothelial cell lines from Eng+/+ and Eng-/- embryos (E9.0). Whereas Eng+/+ cells were only partially growth inhibited by TGFbeta, Eng-/- cells displayed a potent anti-proliferative response. TGFbeta-dependent Smad2 phosphorylation and Smad2/3 translocation were unchanged in the Eng-/- cells. In contrast, TGFbeta treatment led to a more rapid activation of the Smad1/5 pathway in Eng null cells that was apparent at lower TGFbeta concentrations. Enhanced activity of the Smad1 pathway in Eng-/- cells was reflected in higher expression of ALK1-dependent genes such as Id1, Smad6, and Smad7. Analysis of cell surface receptors revealed that the TGFbeta type I receptor, ALK5, which is required for ALK1 function, was increased in Eng-/- cells. TGFbeta receptor complexes were less numerous but displayed a higher binding affinity. These results suggest that endoglin modulates TGFbeta signaling in endothelial cells by regulating surface TGFbeta receptors and suppressing Smad1 activation. Thus an altered balance in TGFbeta receptors and downstream Smad pathways may underlie defects in vascular development and homeostasis.

Reduced endothelial secretion and plasma levels of transforming growth factor-beta1 in patients with hereditary hemorrhagic telangiectasia type 1.

OBJECTIVE: To determine if patients with hereditary hemorrhagic telangiectasia (HHT) show alterations in transforming growth factor (TGF)-beta and its pathways. METHODS: Blood samples were obtained from HHT patients and controls, while endothelial cells were derived from umbilical veins of newborns (HUVEC) from HHT families. TGF-beta1 in plasma, or secreted by HUVEC, and plasma endoglin levels were measured by ELISA. Cellular levels of endoglin and receptor Smad proteins were tested by metabolic labeling and immunoprecipitation, mRNA levels for endoglin and TGF-beta1 by real-time PCR, and receptor Smad phosphorylation by Western blotting. RESULTS: TGF-beta1 and endoglin plasma levels analyzed in 197 individuals showed an inverse correlation with age. Circulating levels of TGF-beta1 were reduced in HHT1 patients (with Endoglin mutations) compared to control, but not in HHT2 patients (with ALK1 mutations). Endoglin levels were unchanged in plasma but decreased in activated monocytes and HUVEC with an HHT1 genotype. These HUVEC also expressed reduced levels of endoglin and TGF-beta1 mRNA, secreted less TGF-beta1, and showed normal receptor Smad expression and phosphorylation. CONCLUSIONS: Decreased plasma TGF-beta1 levels in HHT1 patients correlate with reduced production by endothelial cells. The lower endoglin expression in these cells may alter the regulation of TGF-beta1 via Smad-independent pathways.

A role for endoglin in coupling eNOS activity and regulating vascular tone revealed in hereditary hemorrhagic telangiectasia.

Decreased endothelial NO synthase (eNOS)-derived NO bioavailability and impaired vasomotor control are crucial factors in cardiovascular disease pathogenesis. Hereditary hemorrhagic telangiectasia type 1 (HHT1) is a vascular disorder associated with ENDOGLIN (ENG) haploinsufficiency and characterized by venous dilatations, focal loss of capillaries, and arteriovenous malformations (AVMs). We report that resistance arteries from Eng+/- mice display an eNOS-dependent enhancement in endothelium-dependent dilatation and impairment in the myogenic response, despite reduced eNOS levels. We have found that eNOS is significantly reduced in endoglin-deficient endothelial cells because of decreased eNOS protein half-life. We demonstrate that endoglin can reside in caveolae and associate with eNOS, suggesting a stabilizing function of endoglin for eNOS. After Ca2+-induced activation, endoglin-deficient endothelial cells have reduced eNOS/Hsp90 association, produce less NO, and generate more eNOS-derived superoxide (O2-), indicating that endoglin also facilitates eNOS/Hsp90 interactions and is an important regulator in the coupling of eNOS activity. Treatment with an O2- scavenger reverses the vasomotor abnormalities in Eng(+/-) arteries, suggesting that uncoupled eNOS and resulting impaired myogenic response represent early events in HHT1 pathogenesis and that the use of antioxidants may provide a novel therapeutic modality.

Characterization of 17 novel endoglin mutations associated with hereditary hemorrhagic telangiectasia.

Hereditary hemorrhagic telangiectasia type 1 (HHT1) is a vascular dysplasia caused by mutations in the endoglin (ENG) gene and associated with epistaxis, telangiectases, and a high incidence of pulmonary arteriovenous malformations. To efficiently detect deletions and insertions, we optimized a quantitative multiplex polymerase chain reaction (QMPCR) analysis. We report 17 novel mutations, of which six were detected by QMPCR. Three deletions occurring in intronic sequences were associated with a single copy of exons 9a-14, exon 5, and exons 7-8, respectively. A transient 70kDa monomeric mutant protein resulted from the in-frame deletion of exons 7 and 8 but no mutant protein was present in the other cases. Deletion (in exon 10) or insertion (in exon 7) of two nucleotides, as well as a 1-bp deletion in the small exon 9a were found by QMPCR. Sequencing was required to detect single nucleotide deletions/insertions in exons 2, 5, 6, and 8. No mutant proteins were associated with these frame shift mutations. Two novel splice site mutations resulted in skipping of exons 2 and 4, respectively, while a previously reported intron 3 splice mutant was observed as a de novo mutation. We also report five novel nonsense and missense mutations, including one de novo. Review of the 80 HHT1 families reported to date indicates that 10% would not be resolved by sequencing and that an additional 25% could be revealed by QMPCR performed prior to sequencing. Thus the use of QMPCR accelerates genetic screening for HHT1 and resolves mutations affecting whole exons.

Aspectos da absorçäo no metabolismo do cálcio e vitamina D / Absorption aspects of calcium and vitamin D metabolism

Nesta revisäo, analisam-se os aspectos da absorçäo do cálcio e da vitamina D, comenta-se a necessidade diária do íon, variando com a faixa etária e a suplementaçäo, quando se fizer necessária. Salientam-se as formas de apresentaçäo de cálcio e a quantidade desse elemento nos leites em geral e nos reduzidos em lactose. A vitamina D, fundamental para a absorçäo do cálcio, passa por um processo metabólico complexo ao nível do aparelho digestivo e rins, até a formaçäo do seu metabólito ativo. Comenta-se a importância dos receptores de vitamina D (VDR) nas células intestinais. O cálcio apresenta três etapas no processo absortivo, em que a primeira, intraluminal, sobre influência de vários fatores que aumentam ou diminuem sua absorçäo. A segunda, complexa, é a absorçäo transcelular, dependente de vitamina D. A terceira etapa, plasmática, varia com o nível de albumina, com o pH sérico e outros fatores. Analisando todos os aspectos da absorçäo, pode-se entender melhor a gênese de doenças relacionadas à deficiência destes elementos. Assim sendo, a determinaçäo da causa da perda de massa óssea é importante para uma orientaçäo terapêutica adequada