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This work reports the influence of glyoxal (GO)-derived glycation on the gastrointestinal enzymatic hydrolysis of β-lactoglobulin and β-casein. Reduced digestibility of glycated proteins was found in both gastric and intestinal stage. Distribution of Maillard reaction products in digests with different molecular weight ranges was investigated subsequently. The colorless and brown MRPs largely presented in the digests smaller than 20 kDa. However, the resistance of fluorescent advanced glycation end products (AGEs) to enzymatic hydrolysis gradually increased during glycation, rendering fluorescent AGEs largely present in the digests larger than 20 kDa. No free N (ε)-carboxymethyllysine (CML) was detected in digests. The relative amount of CML in digests larger than 1 kDa was higher than that of Lys, demonstrating the hindrance of CML to enzymatic hydrolysis. This study highlights the resistance of GO-derived AGEs to digestive proteases via blockage of tryptic cleavage sites or steric hindrance, which is a barrier to the absorption of dietary AGEs.

Dehydration-responsive element binding factors (DREBs) play important roles in plant growth, development, and stress signaling pathways in model plants. However, little is known about the function of DREBs in apple (Malus × domestica), a widely cultivated crop that is frequently threatened by drought. We isolated a DREB gene from Malus sieversii (Ledeb.) Roem., MsDREB6.2, and investigated its functions using overexpression analysis and chimeric repressor gene-silencing technology (CRES-T). We identified possible target genes of the protein encoded by MsDREB6.2 using electrophoretic mobility shift assays (EMSAs) and chromatin immunoprecipitation (ChIP). Overexpression of MsDREB6.2 increased the expression of a key cytokinin (CK) catabolism gene, MdCKX4a, which led to a significant reduction in endogenous CK levels, and caused a decrease in shoot:root ratio in transgenic apple plants. Overexpression of MsDREB6.2 resulted in a decrease in stomatal aperture and density and an increase in root hydraulic conductance (L ), and thereby enhanced drought tolerance in transgenic plants. Furthermore, manipulating the level of MsDREB6.2 expression altered the expression of two aquaporin (AQP) genes. The effect of the two AQP genes on L was further characterized using the AQP inhibitor HgCl . Based on these observations, we conclude that MsDREB6.2 enhances drought tolerance and that its function may be due, at least in part, to its influence on stomatal opening, root growth, and AQP expression. These results may have applications in apple rootstock breeding programs aimed at developing drought-resistant apple varieties.

BackgroundApoptosis is regulated in an orderly fashion by a series of genes, and has a crucial role in important physiological processes such as growth development, immunological response and so on. Recently, substantial studies have been undertaken on apoptosis in model animals including humans, fruit flies, and the nematode. However, the lack of genomic data for silkworms limits their usefulness in apoptosis studies, despite the advantages of silkworm as a representative of Lepidoptera and an effective model system. Herein we have identified apoptosis-related genes in the silkworm Bombyx mori and compared them to those from insects, mammals, and nematodes.ResultsFrom the newly assembled genome databases, a genome-wide analysis of apoptosis-related genes in Bombyx mori was performed using both nucleotide and protein Blast searches. Fifty-two apoptosis-related candidate genes were identified, including five caspase family members, two tumor necrosis factor (TNF) superfamily members, one Bcl-2 family member, four baculovirus IAP (inhibitor of apoptosis) repeat (BIR) domain family members and 1 RHG (Reaper, Hid, Grim, and Sickle; Drosophila cell death activators) family member. Moreover, we identified a new caspase family member, BmCaspase-New, two splice variants of BmDronc, and Bm3585, a mammalian TNF superfamily member homolog. Twenty-three of these apoptosis-related genes were cloned and sequenced using cDNA templates isolated from BmE-SWU1 cells. Sequence analyses revealed that these genes could have key roles in apoptosis.ConclusionsBombyx mori possesses potential apoptosis-related genes. We hypothesized that the classic intrinsic and extrinsic apoptotic pathways potentially are active in Bombyx mori. These results lay the foundation for further apoptosis-related study in Bombyx mori.

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Alzheimer's disease is the most common neurodegenerative disease. Until now, there has been no specific medicine that can cure Alzheimer's disease or effectively reverse the disease process. A good dietary pattern is an efficient way to prevent or delay the progression of the disease. Evidence suggests that diet may affect β-amyloid production and tau processing or may regulate inflammation, metabolism, and oxidative stress associated with Alzheimer's disease, which can be exerted by gut microbiota. The gut microbiota is a complex microbial community that affects not only various digestive diseases but also neurodegenerative diseases. Studies have shown that gut microbial metabolites, such as pro-inflammatory factors, short-chain fatty acids, and neurotransmitters, can affect the pathogenesis of Alzheimer's disease. Clinical studies suggested that the gut microbial composition of patients with Alzheimer's disease is different, in particular to lower abundances of Eubacterium rectale and Bacteroides fragilis, which have an antiinflammatory activity. The purpose of this review is to summarize the neuropathological pathogenesis of Alzheimer's disease, and the modulation of dietary patterns rather than single dietary components on Alzheimer's disease through the gut−brain axis was discussed.

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Meat-diet-induced changes in gut microbiota are often accompanied with the development of various metabolic and inflammatory disorders. The exact biochemical mechanism underlying these effects is not well elucidated. This study aims to evaluate how meat proteins in high-fat diets affect tryptophan metabolism in rats. The high-chicken-protein (HFHCH) or high-pork-protein (HFHP) diets increased levels of skatole and indole in cecal and colonic contents, feces, and subcutaneous adipose tissue. The HFHCH and HFHP diets also increased the abundance of Lactobacillus, the Family XIII AD3011 group, and Desulfovibrio in the cecum and colon, which may be involved in the production of skatole and indole. Additionally, high-meat-protein diets induced lower activity of skatole- and indole-metabolizing enzyme CYP2E1 in liver compared with low-meat-protein diets. This work highlights the negative impact of high meat proteins on physiological responses by inducing dysbiosis of gut microbiota and tryptophan metabolism.