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Results from epidemiological and animal studies suggest that consuming soy-containing diets reduces the incidence of certain cancers. The purpose of this presentation was to evaluate the potential of soy protein to prevent occurrence of prostate, breast and colon cancer. Meta-analyses of published epidemiologic studies associating cancer risk with soy intake were performed. The incidence of chemically-induced mammary or colon tumors was determined for rats fed AIN-93G diets made with either casein or soy protein isolate (SPI). Western and Northern blot and microarray analyses were performed on rat mammary and colon tissues to study mechanisms underlying the effects of soy. Meta-analyses revealed reductions in the mean overall risk estimate for mammary (0.78, p < 0.001), colon (0.70, p < 0.001) and prostate (0.66, p < 0.001) cancer for soy consumers. The incidence of AOM-induced colon tumors and DMBA-induced mammary tumors was reduced (p < 0.05) in rats fed SPI-containing diets. Lower incidence of mammary tumors in SPI-fed rats was associated with: 1) reduced terminal end bud numbers (p < 0.05), 2) lower expression of the phase I enzyme CYP1B1 (p < 0.05) and 3) reduced expression of the Ah Receptor and ARNT (p < 0.05). SPI may protect against cancer via multiple mechanisms, including: 1) increased mammary gland differentiation, 2) decreased activation of procarcinogens to carcinogens and 3) regulation of genes in signal transduction pathways underlying tumor initiation, promotion and/or progression.
... It has been recommended by the United States Food and Drug Administration as a healthy food [2]. In addition, the consumption of soy emulsion provides several health benefits, including alleviating the risks of cancer and cardiovascular and neurodegenerative diseases [3]. ...
... A similar structure was found in acid-induced soymilk, which was a 3D stranded gel network with a crosslink among protein polymers [21]. Figure 4 shows the intuitive image of FSPI gastric digestates and their physiochemical characteristics-apparent real time pH, particle size (D [4,3]), soluble protein, and peptide content-during 120 min of gastric digestion. Figure 4 shows the intuitive image of FSPI gastric digestates and their physiochemical characteristics-apparent real time pH, particle size (D [4,3]), soluble protein, and peptide content-during 120 min of gastric digestion. ...
... Figure 4 shows the intuitive image of FSPI gastric digestates and their physiochemical characteristics-apparent real time pH, particle size (D [4,3]), soluble protein, and peptide content-during 120 min of gastric digestion. Figure 4 shows the intuitive image of FSPI gastric digestates and their physiochemical characteristics-apparent real time pH, particle size (D [4,3]), soluble protein, and peptide content-during 120 min of gastric digestion. ...
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This study investigated the effect of lactic-acid-bacteria fermentation on the microstructure and gastrointestinal digestibility of soy proteins using a digestomics approach. Fermented soy protein isolates (FSPIs) under varied fermentation-terminal pH demonstrated a colloidal solution (FSPI-7.0/6.0) or yogurt-like curd (FSPI-5.0/4.0) state. Cryo-electron microscopy figures demonstrated the loosely stacked layer of FSPI-7.0/6.0 samples, whereas a denser gel network was observed for FSPI-5.0/4.0 samples. Molecular interactions shifted from dominant ionic bonds to hydrophobic forces and disulfide bonds. The gastric/intestinal digestion demonstrated that the curd samples afforded a significantly low particle size and high-soluble protein and peptide contents in the medium and late digestive phases. A peptidomics study showed that the FSPI-6.0 digestate at early intestinal digestion had a high peptidome abundance, whereas FSPI curd digestates (FSPI-5.0/4.0) elicited a postponed but more extensive promotion during medium and late digestion. Glycinin G2/G4 and β-conglycinin α/α’ subunits were the major subunits promoted by FSPI-curds. The spatial structures of glycinin G2 and β-conglycinin α subunits demonstrated variations located in seven regions. Glycinin G2 region 6 (A349–K356) and β-conglycinin α subunit region 7 (E556–E575), which were located at the interior of the 3D structure, were the key regions contributing to discrepancies at the late stage.
... Anticancer activity of synthetic lunasin has been studied on mammalian cells against chemical carcinogens and oncogenes RAS and E1A (Jeong et al., 2007;Allen et al., 2009). Several studies on animal models and epidemiologic analyses showed that soy protein can reduce the probability of prostrate, colon and mammary cancer cells (Badger et al., 2005). Studies were also done on 7, 12-dimethylbenz(a)anthracene (DMBA) and methylcholanthrene treated (MCA) fibroblast NIH/3T3 cells line to analyse the anti-cancer property of soybean active peptides (Singh et al., 2014). ...
... Lunasin has structural homology to chromatin binding protein (CBP) (Lumen and O, 2005) and can penetrate into the mammalian cells within a few minutes and accumulate in nucleus in ~18 hours as a result, inhibiting the acetylation of histone proteins. On the other hand, it does not affect the normal cell lines (Badger et al., 2005). Another group of researchers have reported that soybean meal contains certain bioactive peptides that can inhibit the cancer on liver (HepG-2), colon (HCT-116) and ling (NCL-H1299) cell lines at the rate of 70, 73 and 68 per cent, respectively (Rayaprolu et al., 2013). ...
... While diet-based influences in cancer chemoprevention are recognized [10], the compounds coming from the diet or produced secondarily by the microbiota are not well understood. Both nutritive or non-nutritive components (e.g., phytochemicals) present in the diet can influence the process of carcinogenesis [11,12]. ...
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In this study, a comparative, untargeted metabolomics approach was applied to compare urinary metabolite profiles of rats fed irradiated and non-irradiated diets. γ-Irradiated and non-irradiated NIH 7001 diet was given orally to animals beginning 5 days after exposure to the carcinogen N-methyl-N-nitrosourea and continued for 120 days. There was a 36% reduction in mammary tumor incidence in rats consuming the γ-irradiated diet, compared to rats receiving the non-irradiated form of the same diet. Urine samples from rats fed with γ-irradiated and non-irradiated diets were analyzed using nanoLC-MS/MS on a Q-TOF mass spectrometer, collecting positive and negative ion data. Data processing involved feature detection and alignment with MS-DIAL, normalization, mean-centering and Pareto scaling, and univariate and multivariate statistical analysis using MetaboAnalyst, and pathway analysis with Mummichog. Unsupervised Principal Component Analysis and supervised Partial Least Squares-Discriminant Analysis of both negative and positive ions revealed separation of the two groups. The top 25 metabolites from variable importance in projection scores >1 showed their contributions in discriminating urines the γ-irradiated diet fed group from non-irradiated control diet group. Consumption of the γ-irradiated diet led to alteration of several gut microbial metabolites such as phenylacetylglycine, indoxyl sulfate, kynurenic acid, hippurate and betaine in the urine. This study provides insights into metabolic changes in rat urine in response to a γ-irradiated diet which may be associated with mammary cancer prevention.
... Protein isolates have been associated with numerous health and performance-related benefits (Badger et al., 2005;Sharp et al., 2015); however, other areas of health, such as the gut microbiome, can be affected by adding protein isolates into a diet. With a high-protein diet, more dietary proteins and peptides enter the colon for fermentation . ...
Article
Protein isolates are a growing market share in the food industry both as food ingredients and as supplements. All dietary habits can influence and alter the gut microbiome; however, little is known about how protein isolates from different sources will change the composition and function of the gut microbiota under high and low fiber conditions. The study aims to determine the microbiome response to plant and animal protein isolates under high- and low-dietary fiber (H/LDF) conditions. Six commercially available protein isolates (beef, egg white, milk, pea, and two soy protein isolates) were subjected to in vitro enzymatic digestion and dialysis followed by in vitro fermentation with four microbiomes differing in dietary history. Two fermentation media containing 0.1% and 1% fermentable carbohydrate simulated LDF and HDF conditions, respectively. Plant protein isolates, which were all from legumes, had similar amino acid profiles, while the animal protein isolates had very different amino acid profiles depending on source. Under the HDF condition, the microbiome was primarily saccharolytic and there were minimal differences in fermentation properties among the different digested protein isolates. In contrast, under the LDF condition, the microbiome was proteolytic, as evidenced by decreases in peptide concentrations during fermentation and unique shifts in microbiome composition and function during fermentation of the digested protein isolates. Under the LDF condition, digested milk protein isolate increased the abundance of bacteria in the Clostridia class and the Firmicutes phylum with concomitant increases in butyrate production. Flavonifractor and Intestinimonas, genera with butyrate-producing pathways, were identified as differentially abundant genera associated with digested milk protein isolate after 24 h of fermentation. Soy proteins also resulted in high butyrate production, but induced increases in Uncl_Lachnospiraceae, Lachnoclostridium, and Butyricicoccus genera, suggesting a different pathway for butyrate production compared with digested milk protein isolate. Although digested milk protein and soy protein isolates resulted in high butyrate production, they also led to the highest concentrations of undesirable protein fermentation metabolites, ammonia and cadaverine, during fermentation. Several amino acids were found to be significantly correlated to metabolite production under the LDF condition, with glutamate and proline having a significantly positive correlation with butyrate production. In conclusion, digested protein isolates have differential effects on the gut microbiome, but only under conditions where dietary fiber is limited. Notably, digested milk and soy protein isolates were highly butyrogenic and increased abundance of some beneficial gut microbial taxa, but also led to high concentration of deleterious protein fermentation metabolites. Advisor: Devin J. Rose
... The investigators found that, through stimulating the TGF pathway, fermented soybean extracts may effectively prevent breast cancer. According to Badger et al. (135), soy peptide concentrates reduce the incidence of breast, prostate, and gastrointestinal cancers. They claimed that soy peptide concentrates could reduce cancer incidence by 80%. ...
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Bioactive peptides generated from food proteins have great potential as functional foods and nutraceuticals. Bioactive peptides possess several significant functions, such as antioxidative, anti-inflammatory, anticancer, antimicrobial, immunomodulatory, and antihypertensive effects in the living body. In recent years, numerous reports have been published describing bioactive peptides/hydrolysates produced from various food sources. Herein, we reviewed the bioactive peptides or protein hydrolysates found in the plant, animal, marine, and dairy products, as well as their by-products. This review also emphasizes the health benefits, bioactivities, and utilization of active peptides obtained from the mentioned sources. Their possible application in functional product development, feed, wound healing, pharmaceutical and cosmetic industries, and their use as food additives have all been investigated alongside considerations on their safety.
... Among the plant-based biopeptides with anticancer benefits, those obtained from soybean proteins have been attracting particular research interests (Badger et al., 2005;Hwang et al., 2011). In a study by Rayaprolu et al. (2013), high oleic acid soybean protein from N98-4445A and S03-543CR lines was hydrolysed using Alcalase and the released biopeptides inhibited the proliferation of colon, liver and lung cancer cells. ...
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Due to the rapid growth in the global population, the consumption of animal-based food products/food compounds has been associated with negative implications for food sustainability/security. As a result, there is an increasing demand for the development of plant-based food and compounds as alternatives. Meanwhile, a growing number of studies report the health benefits of food protein-based peptides prepared via enzymatic hydrolysis and exhibiting biological properties such as antioxidant, antihypertensive, anti-thrombotic, and antidiabetic activities. However, the inherent bitterness of some peptides hinders their application in food products as ingredients. This article aims to provide the latest findings on plant-based bioactive peptides, particularly their health benefits, manufacturing methods, detection and qualification of their bitterness properties, as well as debittering methods to reduce or eliminate this negative sensory characteristic. However, there is still a paucity of research on the biological property of debittered peptides. Therefore, the role of plant protein-derived bioactive peptides to meet the health targets of the Sustainable Development Goals can only be realised if advances are made in the industrial-scale bioprocessing and debittering of these peptides.
... The authors concluded that the fermented soybean extracts might be beneficial for preventing breast cancer by a TGFβ pathway-activating mechanism. Badger, Ronis, Simmen, and Simmen (2005) reported that the soy peptide isolates reduce the incidence of certain cancers such as breast, prostate and gastro-intestinal. They asserted that the use of soy peptide isolates may prevent the risk of tumour incidence by 80%. ...
Article
Agro-industrial by-products containing considerable amounts of protein (10 – 50%) such as soybean meal, rice bran and coconut pulp are promising bioactive peptide sources with annual disposal rate of 800 million tons in the world. More recently, plant by-products rich in protein content have been studied under various prisms that include recovery techniques, peptide production methods, determination of technological benefits and functional properties, and their applications in foods. The researches in bioactive peptides provide evidence over the techno-functional properties and the health benefits are highly dependent upon their amino acid sequences, molecular weights, conformations and surface properties. Research findings compared bioactive properties of the obtained peptides with respect to their amino acid sequences and also reported that hydrophobic/hydrophilic properties have direct effect on both functional and health effects. In addition, the resultant properties of the peptides could be affected by the conducted extraction method (alkaline, enzymatic, ultrasound assisted, microwave assisted, etc.), extraction solvent, precipitation and purification techniques and even by the final drying process (spray, freeze, vacuum, etc.) which may alter molecular weights, conformations and surface properties. Latest studies have investigated solubility, emulsifying, foaming, water/oil holding capacity and surface properties and also antioxidant, antimicrobial, anticarcinogenic, hypocholesterolemic, antihypertensive, immunomodulatory and opioid activities of bioactive peptides obtained from plant by-products. Moreover, the application of the bioactive peptides into different food formulations has been a recent trend of functional food development. These bioactive peptides’ bitter taste and toxicity are possible challenges in some cases that need to be resolved before their wider utilization.
... The uptake of soy, an important source of phytoestrogens and isoflavones, like daidzein (4′,7dihydroxyisoflavone) and genistein (4′,5,7-trihydroxyisoflavone), was found to significantly correlate with a decreased risk of developing breast cancer (OR 0.78). This could be due to: (1) increased differentiation of the mammary tissue, (2) reduced bio-activation and bio-transformation from procarcinogens to carcinogens and (3) modulation of genes belonging to signal transduction pathways and cascades underlying tumor initiation, promotion and/or progression, such as the BRCA1/BRCA2 pathway [29]. ...
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Proper nutrition plays a major role in preventing diseases and, therefore, nutritional interventions constitute crucial strategies in the field of Public Health. Nutrigenomics and nutriproteomics are arising from the integration of nutritional, genomics and proteomics specialties in the era of postgenomics medicine. In particular, nutrigenomics and nutriproteomics focus on the interaction between nutrients and the human genome and proteome, respectively, providing insights into the role of diet in carcinogenesis. Further omics disciplines, like metabonomics, interactomics and microbiomics, are expected to provide a better understanding of nutrition and its underlying factors. These fields represent an unprecedented opportunity for the development of personalized diets in women at risk of developing breast cancer.
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Legitimate nutrition assumes a significant role in preventing diseases and, in this way, nutritional interventions establish vital strategies in the area of public health. Nutrigenomics centres on the different genes and diet in an individual and how an individual’s genes influence the reaction to bioactive foodstuff. It targets considering the genetic and epigenetic interactions with nutrients to lead to a phenotypic alteration and consequently to metabolism, differentiation, or even apoptosis. Nutrigenomics and lifestyle factors play a vital role in health management and represent an exceptional prospect for the improvement of personalized diets to the individual at risk of developing diseases like cancer. Concerning cancer as a multifactorial genetic ailment, several aspects need to be investigated and analysed. Various perspectives should be researched and examined regarding the development and prognosis of breast and colon cancer. Malignant growth occurrence is anticipated to upsurge in the impending days, and an effective anticipatory strategy is required. The effect of dietary components, basically studied by nutrigenomics, looks at gene expression and molecular mechanisms. It also interrelates bioactive compounds and nutrients because of different 'omics' innovations. Several preclinical investigations demonstrate the pertinent role of nutrigenomics in breast and colon cancer, and change of dietary propensities is conceivably a successful methodology for reducing cancer risk. The connection between the genomic profile of patients with breast or colon cancer and their supplement intake, it is conceivable to imagine an idea of personalized medicine, including nutrition and medicinal services.
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The consumption of soy milk is increasing worldwide for its nutritional value and health benefits, however, its protein composition after commercialization is not well known. Technological and thermal treatments to which soy milk is subjected could affect the protein composition of the commercial products. This study compared the protein profile of 15 different commercial soy milks using a label-free quantitative proteomics approach. Proteins related to nutrient reservoir activity, endopeptidase inhibitor activity, lipid binding, and seed maturation contribute the most in terms of percentage mass. Their associated Gene Ontology terms are also enriched. Samples clustered into three groups based on their protein composition, with glycinins and beta-conglycinins being the most influential for determining the clustering. Amino acid composition estimated from the proteomics data also reflects the clustering of samples. Twenty allergenic proteins varying in abundance were identified, with Gly m 5 and Gly m 6 being the predominantly abundant allergens.
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There are suspected links between an animal's diet, differentiation status of a target tissue, and sensitivity to chemically induced cancer. We have demonstrated that rats fed AIN93G diets made with soy protein isolate (SPI) or whey protein hydrolysate (WPH) had a lower incidence of 7,12-dimethylbenz(a)anthracene (DMBA)-induced adenocarcinoma than rats fed the same diet made with casein (CAS). The current study was conducted to determine the differentiation status of the mammary glands during development. Offspring of rats (n = 5-10/group) were fed diets made with SPI, WPH, or CAS throughout life (beginning on gestation day 4) and were sacrificed on postnatal day (PND) 21, PND 33, PND 50 or on metaestrous between PND 48 and PND 51. There were no significant differences between the numbers of mammary terminal end buds (TEBs) or lobuloalveoli (LOB) between any of the diets groups at PND 21 or PND 33, but at PND 50 there was an 75% decrease in the mean numbers of TEBs/ mm 2 in the SPI- or WPH-fed rats, compared with the CAS-fed rats (p = 0.09 and p = 0.06, respectively). In rats sacrificed in metaestrous, there were no significant differences in the proliferation index (PI) in the TEBs or LOB between any of the diet groups. In metaestrous rats, there were twice as many cells expressing estrogen receptor β (ERβ; ∼60%) compared with estrogen receptor a (ERa; ∼30%) in the LOB and 1.5 times more ERβ (∼60%) compared with estrogen receptor a (ERa, ∼40%) in the TEBs. There were no diet-dependent differences in expression of ERα and ERβ. Similarly, there were no differences between the diet groups in progesterone receptor (PR) expressing LOB cells. However, in the TEBs there was a diet-dependent difference in PR positive cells with a 34% increase (p < 0.05) in the SPI-fed rats and a 38% increase (p < 0.05) in the WPH-fed rats compared with the CAS-fed rats. These results show that the type of dietary protein alters the phenotype of mammary epithelia in the TEBs. The SPI- and WPH-dependent changes in mammary differentiation may contribute to the reduced sensitivity to DMBA-induced mammary cancer in rats fed these proteins.
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Aberrant crypt foci of the colon are possible precursors of adenoma and cancer, but these lesions have been studied mainly in surgical specimens from patients who already had colon cancer. Using magnifying endoscopy, we studied the prevalence, number, size, and dysplastic features of aberrant crypt foci and their distribution according to age in 171 normal subjects, 131 patients with adenoma, and 48 patients with colorectal cancer. We also prospectively examined the prevalence of aberrant crypt foci in 11 subjects (4 normal subjects, 6 with adenoma, and 1 with cancer) before and after the administration of 100 mg of sulindac three times a day for 8 to 12 months and compared the results with those in 9 untreated subjects (4 normal subjects and 5 with adenoma). All 20 subjects had aberrant crypt foci at base line. We identified 3155 aberrant crypt foci, 161 of which were dysplastic; the prevalence and number increased with age. There were significant (P<0.001) correlations between the number of aberrant crypt foci, the presence of dysplastic foci, the size of the foci, and the number of adenomas. After sulindac therapy, the number of foci decreased, disappearing in 7 of 11 subjects. In the untreated control group, the number of foci was unchanged in eight subjects and slightly increased in one (P<0.001 for the difference between the groups). Aberrant crypt foci, particularly those that are large and have dysplastic features, may be precursors of adenoma and cancer.
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A study was conducted to determine the protective effects of two common dietary proteins, soy protein isolate (soy) and bovine whey, against chemically induced mammary tumors in female Sprague Dawley rats. Rats were fed AIN-93G diets having casein, soy, or whey as the sole protein source. Rats within the same dietary groups were mated to obtain the F1 and F2 generations. At age 50 days, F1 (experiment A) or F2 (experiment B) female offspring (> or =19 rats/group) were p.o. gavaged with 80 mg/kg 7,12-dimethylbenz(a)anthracene, and mammary glands were evaluated when 100% of the casein-fed group developed at least one palpable tumor. Rats grew well on all three diets, but casein-fed rats gained slightly more body weight than soy- or whey-fed rats (P < 0.05). Vaginal opening occurred 1 day earlier in soy-fed rats than in casein- or whey-fed rats, but no other differences in reproductive and developmental parameters were observed between groups. When 50% of the casein-fed rats had at least one mammary tumor, lower tumor incidences (24-34%) were observed in the soy-fed (P < 0.009) and whey-fed groups (P < 0.001). When 100% of the casein-fed rats had at least one tumor, soy-fed rats had a lower tumor incidence (77%) in experiment B (P < 0.002), but not in experiment A (P < 0.12), and there were no differences in tumor multiplicity. Whey-fed rats had lower mammary tumor incidence (54-62%; P < 0.002) and multiplicity (P < 0.007) than casein-fed rats in both experiments. Our results indicate that diets rich in soy reduce the incidence of chemically induced mammary tumors by approximately 20%. Furthermore, whey appears to be at least twice as effective as soy in reducing both tumor incidence and multiplicity.
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Male Sprague-Dawley rats (F2 generation) that had been fed modified American Institute of Nutrition-93G diets formulated with a single protein source of either casein or soy protein isolate for their entire life received azoxymethane once a week for 2 weeks (s.c., 15 mg/kg) starting at age 90 days. Forty weeks later, all rats were euthanized, the colon was examined visually for masses and these were subsequently evaluated histologically. Rats fed the casein diet had a 50% incidence of colon tumors compared with 12% on soy protein-based diets (P<0.05). These results suggest that consumption of soy protein-containing diets may reduce the risk of developing colon tumors.