Protective effect of diet supplemented with rice prolamin extract against DNCB-induced atopic dermatitis in BALB/c mice.

BACKGROUND: Rice prolamin has been reported to possess antioxidative, anti-inflammatory and immune-promoting properties. This study is aimed to examine the protective effects of dietary rice prolamin extract (RPE) against dinitrochlorobenzene (DNCB)-induced atopic dermatitis (AD)-like skin lesions in mice. METHODS: BALB/c mice were fed diet supplemented with 0-0.1 % RPE for 6 weeks. For the last 2 weeks, 1 % or 0.2 % DNCB was applied repeatedly to the back skin of mice to induce AD-like lesions. Following AD induction, the severity of skin lesions was examined macroscopically and histologically. In addition, the serum levels of IgE, IgG1 and IgG2a were determined by ELISA, and the mRNA expression of IL-4 and IFN-γ in the skin was determined by real-time PCR. RESULTS: Dietary RPE suppressed the clinical symptoms of DNCB-induced dermatitis as well as its associated histopathological changes such as epidermal hyperplasia and infiltration of mast cells and eosinophils in the dermis. RPE treatment also suppressed the DNCB-induced increase in transepidermal water loss. Dietary RPE inhibited the DNCB-induced enhancement of serum IgE and IgG1 levels, whereas it increased the serum IgG2a level in DNCB-treated mice. In addition, dietary RPE upregulated the IFN-γ mRNA expression and downregulated the IL-4 mRNA expression in the skin of DNCB-treated mice. CONCLUSIONS: The above results suggest that dietary RPE exerts a protective effect against DNCB-induced AD in mice via upregulation of Th1 immunity and that RPE may be useful for the treatment of AD.

Rice prolamin extract ameliorates acute murine colitis by inhibiting nuclear factor-kappa B and modulating intestinal apoptosis and cell proliferation.

We investigated the impact of rice prolamin extract (RPE) on lipopolysaccharide (LPS)-induced nuclear factor (NF)-κB signalling in intestinal epithelial cells and macrophages, and determined the therapeutic efficacy of RPE in acute murine colitis. The effect of RPE on LPS-induced NF-κB signalling and proinflammatory gene expression was evaluated by reverse transcription-polymerase chain reaction (RT-PCR), Western blotting, immunofluorescence and electrophoretic mobility shift assay (EMSA). The in-vivo efficacy of RPE was assessed in mice with 3% dextran sulphate sodium (DSS)-induced colitis. Apoptotic and cellular proliferative activities were evaluated by immunostaining with cleaved caspase-3 and proliferating cell nuclear antigen (PCNA) antibodies. RPE inhibited LPS-induced expression of monocyte chemotactic protein (MCP)-1, interleukin (IL)-6 and tumour necrosis factor (TNF)-alpha and LPS-induced NF-κB signalling in intestinal epithelial cells and macrophages. RPE-fed, DSS-exposed mice showed less weight loss, longer colon length and lower histological score compared to control diet-fed, DSS-exposed mice. Immunostaining analysis revealed a significant decrease of cleaved caspase-3 positive cells in RPE-fed, DSS-exposed mice compared to DSS-exposed mice. Also, the number of PCNA-positive cells within intact colonic crypts decreased significantly in RPE-fed, DSS-exposed mice compared to control diet-fed, DSS-exposed mice. DSS-induced NF-κB signalling was inhibited by RPE. RPE ameliorates intestinal inflammation by inhibiting NF-κB activation and modulating intestinal apoptosis and cell proliferation in an acute murine colitis.

Biopolymer-Assembled Porous Hydrogel Microfibers from Microfluidic Spinning for Wound Healing.

Hydrogels are considered as a promising medical patch for wound healing. Researches in this aspect are focused on improving their compositions and permeability to enhance the effectiveness of wound healing. Here, novel prolamins-assembled porous hydrogel microfibers with the desired merits for treating diabetes wounds are presented. Such microfibers are continuously generated by one-step microfluidic spinning technology with acetic acid solution of prolamins as the continuous phase and deionized water as the dispersed phase. By adjusting the prolamin concentration and flow rates of microfluidics, the porous structure and morphology as well as diameters of microfibers can be well tailored. Owing to their porosity, the resultant microfibers can be employed as flexible delivery systems for wound healing actives, such as bacitracin and vascular endothelial growth factor (VEGF). It is demonstrated that the resultant hydrogel microfibers are with good cell-affinity and effective drug release efficiency, and their woven patches display superior in vivo capability in treating diabetes wounds. Thus, it is believed that the proposed prolamins-assembled porous hydrogel microfibers will show important values in clinic wound treatments.

Two prolamin peptides from durum wheat preclude celiac disease-specific T cell activation by gluten proteins.

PURPOSE: Celiac disease (CD) is a permanent intolerance to wheat prolamins and related proteins displayed by genetically susceptible individuals. Blocking or modulation of CD-specific T cell response by altered prolamin peptides are currently considered as a potential alternative to the only effective therapy of CD based on a life-long gluten-free diet. Two prolamin peptides, the 9-mer ASRVAPGQQ and the 10-mer GTVGVAPGQQ sequences, were identified by mass spectrometry in the peptic/tryptic digest of prolamins (PTP) from durum wheat (Triticum turgidum ssp. durum) cv. Adamello, and investigated for their ability to preclude the stimulation of CD-specific mucosal T cells by gluten proteins. METHODS: Gluten-specific polyclonal intestinal T cell lines from five CD children (mean age 5 years) were exposed to 50 microg/ml of a deamidated PTP from whole flour of common wheat (T. aestivum) cv. San Pastore, and tested for proliferation and production of interferon-gamma (INF-gamma) and interleukin 10 (IL-10). The same experiment was performed in the presence of 20 microg/ml of the 9-mer or the 10-mer peptide. RESULTS: T cells exposed to PTP showed a threefold increase in proliferation and INF-gamma production, and a significant (P

Hypoglycemic Effect of Prolamin from Cooked Foxtail Millet (Setaria italic) on Streptozotocin-Induced Diabetic Mice.

Millet proteins have been demonstrated to possess glucose-lowering and lipid metabolic disorder modulation functions against diabetes; however, the molecular mechanisms underlying their anti-diabetic effects remain unclear. The present study aimed to investigate the hypoglycemic effect of prolamin from cooked foxtail millet (PCFM) on type 2 diabetic mice, and explore the gut microbiota and serum metabolic profile changes that are associated with diabetes attenuation by PCFM. Our diabetes model was established using a high-fat diet combined with streptozotocin before PCFM or saline was daily administrated by gavage for 5 weeks. The results showed that PCFM ameliorated glucose metabolism disorders associated with type 2 diabetes. Furthermore, the effects of PCFM administration on gut microbiota and serum metabolome were investigated. 16S rRNA gene sequencing analysis indicated that PCFM alleviated diabetes-related gut microbiota dysbiosis in mice. Additionally, the serum metabolomics analysis revealed that the metabolite levels disturbed by diabetes were partly altered by PCFM. Notably, the decreased D-Glucose level caused by PCFM suggested that its anti-diabetic potential can be associated with the activation of glycolysis and the inhibition of gluconeogenesis, starch and sucrose metabolism and galactose metabolism. In addition, the increased serotonin level caused by PCFM may stimulate insulin secretion by pancreatic ß-cells, which contributed to its hypoglycemic effect. Taken together, our research demonstrated that the modulation of gut microbiota composition and the serum metabolomics profile was associated with the anti-diabetic effect of PCFM.

Dietary Japanese millet protein ameliorates plasma levels of adiponectin, glucose, and lipids in type 2 diabetic mice.

Millet is an important food crop in Asia and Africa, but the health benefits of dietary millet are little known. This study defined the effects of dietary Japanese millet on diabetic mice. Feeding of a high-fat diet containing Japanese millet protein concentrate (JMP, 20% protein) to type 2 diabetic mice for 3 weeks significantly increased plasma levels of adiponectin and high-density lipoprotein cholesterol (HDL cholesterol) and decreased the levels of glucose and triglyceride as compared to control. The starch fraction of Japanese millet had no effect on glucose or adiponectin levels, but the prolamin fraction beneficially modulated plasma glucose and insulin concentrations as well as adiponectin and tumor necrosis factor-alpha gene expression. Considering the physiological significance of adiponectin and HDL cholesterol levels in type 2 diabetes, insulin resistance, and cardiovascular disease, our findings imply that dietary JMP has the potential to ameliorate these diseases.

Rice protein prolamin promotes anti-leukemia immunity and inhibits leukemia growth in vivo.

Prolamin is a heat-stable storage protein of rice (Oryza sativa). This study aimed to examine the effect of prolamin on anti-tumor immune response in vitro and leukemia growth in vivo. The prolamin-enriched rice fractions were prepared to stimulate peripheral blood mononuclear cells (MNC) from mice spleen. The MNC-conditioned medium (MNC-CM) was collected to treat leukemia L1210 cells. Human MNC-CM was prepared to treat Jurkat acute T cell leukemia cells. Purified prolamin was orally administered to syngeneic L1210-bearing DBA/2 mice to assess weights of tumor, liver and spleen, liver histopathology, peripheral blood neutrophil count and cytokine levels. Prolamin-prepared MNC-CM inhibited the viability of murine leukemia L1210 cells and human leukemia Jurkat cells, indicating an immunomodulatory effect. In syngeneic L1210-bearing DBA/2 mice, oral administration of purified prolamin dose-dependently decreased the tumor weight and attenuated the leukemia-induced reduction of liver and spleen weights. Prolamin inhibited the increase of peripheral blood leukocyte count. The levels of tumor necrosis factor-α and interferon-γ in MNC-CM and mice serum were significantly increased by prolamin treatment. No significant change in body weight, serum alanine aminotransferase and creatinine levels was noted by prolamin treatment. Rice prolamin could effectively promote anti-tumor immunity and inhibit leukemia growth without significant toxicity.

Variable activation of immune response by quinoa (Chenopodium quinoa Willd.) prolamins in celiac disease.

BACKGROUND: Celiac disease is an enteropathy triggered by dietary gluten found in wheat, barley, and rye. The current treatment is a strict gluten-free diet. Quinoa is a highly nutritive plant from the Andes, with low concentrations of prolamins, that has been recommended as part of a gluten-free diet; however, few experimental data support this recommendation. OBJECTIVE: We aimed to determine the amount of celiac-toxic prolamin epitopes in quinoa cultivars from different regions of the Andes and the ability of these epitopes to activate immune responses in patients with celiac disease. DESIGN: The concentration of celiac-toxic epitopes was measured by using murine monoclonal antibodies against gliadin and high-molecular-weight glutenin subunits. Immune response was assessed by proliferation assays of celiac small intestinal T cells/interferon-γ (IFN-γ) and production of IFN-γ/IL-15 after organ culture of celiac duodenal biopsy samples. RESULTS: Fifteen quinoa cultivars were tested: 4 cultivars had quantifiable concentrations of celiac-toxic epitopes, but they were below the maximum permitted for a gluten-free food. Cultivars Ayacuchana and Pasankalla stimulated T cell lines at levels similar to those for gliadin and caused secretion of cytokines from cultured biopsy samples at levels comparable with those for gliadin. CONCLUSIONS: Most quinoa cultivars do not possess quantifiable amounts of celiac-toxic epitopes. However, 2 cultivars had celiac-toxic epitopes that could activate the adaptive and innate immune responses in some patients with celiac disease. These findings require further investigation in the form of in vivo studies, because quinoa is an important source of nutrients for patients with celiac disease.

Analysis of protein fractions and some minerals present in chan (Hyptis suaveolens L.) seeds.

UNLABELLED: Chan (Hyptis suaveolens L.) seeds have been used as food as well as in traditional medicine in several countries of America, Asia and Africa. Chan seed protein content was 13.9% on dry weight basis. Analysis of its protein composition showed 39% globulins, 36% glutelins, 24% albumins, and 1% prolamins. By defatting the flour with chloroform/methanol, it increased the extracted proteins and improved the protein band resolution after SDS-PAGE, showing 5 albumin bands, 8 globulin bands, and 2 prolamin and glutelin bands. The aromatic amino acid content in chan seeds is higher than those of other grains including maize, with good levels of branched chain amino acids. In general, except for lysine, it has a well-balanced amino acid composition, providing a good supply of almost all the essential amino acids for the different age groups. Magnesium content was high, whereas calcium, potassium, and phosphorous were in the average range when compared to barley, oat, rice, and wheat. The present results indicate that seeds from the chan plant could be relevant because of their nutritional properties and they have the potential to be widely used in the production of high-quality food. PRACTICAL APPLICATION: Chan seeds are presently used in a very limited manner as a food source; however, considering their high quality composition, they have the potential for a more extended use in the food industry.

T-cell response to different cultivars of farro wheat, Triticum turgidum ssp. dicoccum, in celiac disease patients.

BACKGROUND & AIMS: Celiac disease is a gluten sensitive disorder that occurs in genetically susceptible individuals. The present study deals with variation in the immune response of mucosal T-cells from celiac children to prolamins extracted from nine landraces of farro wheat (Triticum turgidum ssp. dicoccum) with contrasting storage protein compositions. METHODS: The prolamin fraction from nine 'dicoccum' wheat landraces was subjected to peptic-tryptic digestion and supplied to T-cells from mucosal explants of four celiac patients. Immune reactions in terms of cell proliferation and INF-gamma secretion by intestinal T lymphocytes were then determined. RESULTS: T-cell lines exposed to digested prolamins from landraces L5563, L5558 and L5540 showed negligible proliferative responses and released INF-gamma amounts similar to that of untreated control cells. By contrast, landraces Ersa 6, Ersa 8, Leonessa 4 and Leonessa 5 proved to be very active in triggering the immune responses, whereas landraces Filosini and Prometeo exhibited an intermediate behavior. One-dimensional fractionations by A-PAGE or SDS-PAGE revealed distinctive prolamin patterns amongst the landraces analysed. CONCLUSIONS: 'Dicoccum' wheat represents a heterogeneous species showing a wide variation in both prolamin composition and T-cell immunological activation, some 'dicoccum' landraces being poor in or devoid of noxious gluten proteins.