Analysis of protein glycosylation within the nematode Caenorhabditis elegans has revealed an abundant and unreported set of core chitobiose modifications (CCMs) to N-linked glycans. With hydrazine release, an array of glycomers and isobars were detected with hexose extensions on the 3- and 3,6-positions of the penultimate and reducing terminus, respectively. A full complement of structures includes a range of glycomers possessing a Galbeta(1-4)Fuc disaccharide at the 3- and 6-positions of the protein-linked GlcNAc. Importantly, enzymatic (PNGase F/A) release failed to liberate many of these extended structures from reduced and alkylated peptides and, as a consequence, such profiles were markedly deficient in a representation of the worm glycome. Moreover, the 3-linked Galbeta(1-4)Fuc moiety was notably resistant to a range of commercial galactosidases. For identification, the fragments were spectrum-matched with synthetic products and library standards using sequential mass spectrometry (MS(n)). A disaccharide observed at the 3-position of penultimate GlcNAc, indicating a Hex-Fuc branch on some structures, was not further characterized because of low ion abundance in MS(n). Additionally, a Hex-Hex-Fuc trisaccharide on the 6-position of proximal GlcNAc was also distinguished on select glycomers. Similar branch extensions on 6-linked core fucosyl residues have recently been reported among other invertebrates. Natural methylation and numerous isobars complement the glycome, which totals well over 100 individual structures. Complex glycans were detected at lower abundance, indicating glucosaminyltransferase-I (GnT-I) and GnT-II activity. A range of phosphorylcholine (PC)-substituted complex glycans were also confirmed following a signature two-stage loss of PC during MS(n) analysis, although the precursor ion was not observed in the mass profiles. In a similar manner, numerous other minor glycans may be present but unobserved in hydrazine-release profiles dominated by fucosylated structures. All CCM structures, including multiple isomers, were determined without chromatography by gas-phase disassembly (MS(n)) in Paul and linear ion trap (IT) instruments.

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Obesity and type 2 diabetes mellitus (DM) have grown in prevalence around the world, and recently, related diseases have been considered epidemic. Given the high cost of treatment of obesity/DM-associated diseases, strategies such as dietary manipulation have been widely studied; among them, the whey protein diet has reached popularity because it has been suggested as a strategy for the prevention and treatment of obesity and DM in both humans and animals. Among its main actions, the following activities stand out: reduction of serum glucose in healthy individuals, impaired glucose tolerance in DM and obese patients; reduction in body weight; maintenance of muscle mass; increases in the release of anorectic hormones such as cholecystokinin, leptin, and glucagon like-peptide 1 (GLP-1); and a decrease in the orexigenic hormone ghrelin. Furthermore, studies have shown that whey protein can also lead to reductions in blood pressure, inflammation, and oxidative stress.

Ao se fazer a recomendação de proteína para diferentes grupos populacionais [13], além da composição aminoacídica (SARWAR et al., 1997) [28], devem ser consideradas a quantidade total de nitrogênio e a digestibilidade da mistura protéica. Uma mistura protéica de QUALIDADE NUTRICIONAL E ESCORE QUÍMICO DE AMINOÁCIDOS DE DIFERENTES FONTES PROTÉICAS SUMMARYNUTRITIONAL QUALITY AND CHEMICAL SCORE OF AMINO ACIDS FROM DIFFERENT PROTEIN SOURCES. Proteins are essential for animals, therefore, they must be present in diet, in appropriate amounts. Besides the quantitative aspect, the qualitative aspect should be taken into account, i.e. its nutritional value, which will depend on its composition, digestibility, bioavailability of essential amino acids, absence of toxicity, and of antinutritional factors. The purpose of this work was to evaluate the digestibility in vivo, the chemical score of amino acids (EQ), and the protein digestibility corrected amino acid score (PDCAAS) of the following protein resources: frog meat without bone, frog meat with bone, mechanically separated frog meat (CMS), beef meat, egg powder, casein, wheat, corn, conventional soybean, Kunitz trypsin inhibitor and lipoxygenase free soybean (KTI-LOX-soybean), textured soybean protein (PTS) and beans. Animal proteins presented higher digestibility values than those from vegetables. Frog meat without bone was the protein with the highest protein digestibility of all proteins studied, not differing from casein, CMS, beef and frog meat with bone. Comparing animal proteins, the one of egg powder was the one which presented the lowest digestibility. No animal protein presented essential limiting amino acids when compared to those of FAO/WHO. Beans, conventional soybean, KTI-LOX-soybean and PTS presented sulfurized amino acids (methione+cysteine) as limiting ones. Whereas for wheat and corn, the most limiting amino acid was lysine. KTI-LOX-soybean presented higher PDCAAS values than those of conventional soybean, presenting a possible increase in genetically improved soybean and processed soybean protein quality. Keywords: protein quality, digestibility, PDCAAS, essential amino acids. A digestibilidade é a medida da porcentagem das proteínas que são hidrolisadas pelas enzimas digestivas e absorvidas pelo organismo na forma de aminoácidos ou de qualquer outro composto nitrogenado. Trata-se de um determinante da qualidade protéica da dieta. Quando certas ligações peptídicas não são hidrolisadas no processo digestivo, parte da proteína é excretada nas fezes ou transformada em produtos do metabolismo pelos microorganismos do intestino grosso [30].

BackgroundIt is well known that high fat diets (HFDs) induce obesity and an increase in proinflammatory adipokines. Interleukin-6 (IL-6) is considered the major inflammatory mediator in obesity. Obesity is associated with a vitamin deficiency, especially of vitamins E and D3. We examined the effects of vitamin D3 and vitamin E supplementation on levels of IL-6 and IL-10 (as a marker of anti-inflammatory cytokines since, a balance between pro- and anti-inflammatory cytokines is maintained) protein expression in adipose tissue of mice provided with an HFD. Additionally, we measured the effects of vitamin E and vitamin D3 treatment on LPS-stimulated 3T3-L1 adipocytes IL-6 and IL-10 secretion.ResultsIL-6 protein levels and the IL-6/IL-10 ratio were decreased in epididymal white adipose tissue in groups receiving vitamins E and D3 supplementation compared to the HFD group. A 24-hour treatment of vitamin D3 and vitamin E significantly reduced the IL-6 levels in the adipocytes culture medium without affecting IL-10 levels.ConclusionsVitamin D3 and vitamin E supplementation in an HFD had an anti-inflammatory effect by decreasing IL-6 production in epididymal adipose tissue in mice and in 3T3-L1 adipocytes stimulated with LPS. Our results suggest that vitamin E and D3 supplementation can be used as an adjunctive therapy to reduce the proinflammatory cytokines present in obese patients.