Project description:Milk-derived peptides and milk fat globule membrane (MFGM) have gained interest as health-promoting food ingredients. However, the mechanisms by which these nutraceuticals modulate the function of biological systems often remain unclear. We utilized Caenorhabditis elegans to elucidate how milk-derived Protein powders rich in MFGM, previously used in a clinical trial, affect the physiology of this model organism. Our results demonstrate that Protein powders do not affect lifespan but promote the fitness of the animals. Surprisingly, gene expression analysis revealed that Protein powders decrease the expression of genes functioning on innate immunity, which also translates into reduced survival on pathogenic bacteria. One of the innate immunity-associated genes showing reduced expression upon Protein powder supplementation is cpr-3, the homolog of human cathepsin B. Interestingly, knockdown of cpr-3 enhances fitness, but not in Protein powder-treated animals, suggesting that protein powders contribute to fitness by downregulating the expression of this gene. In summary, this research highlights the value of C. elegans in testing the biological activity of food supplements and nutraceuticals. Furthermore, this study should encourage investigations into whether milk-derived peptides and MFGM mediate their beneficial effects through the modulation of cathepsin B expression in humans.
Project description:Very little is known about miRNAs found in breastmilk cells, which also reflect the cells of the lactating mammary epithelium. Our hypothesis is that breastmilk cells are richer in miRNA compared to other milk fractions, such as skim milk. Further, the effects of milk removal by the infant on milk cell miRNA content and/or composition have not been investigated. Breastmilk cells conserved higher miRNA content than previously published lipid and skim fractions of breastmilk as well as other known sources of miRNA in humans. Specifically, 1,467 known mature miRNAs were identified and a further 1996 novel miRNAs, of which 89 were highly expressed. As previously shown, post-feed milk contained more cells than pre-feed milk, and the same was observed for miRNA content. However, no statistically significant difference was found in the expression of the total known and novel miRNAs between pre- and post-feed milk (p=0.76), although 27 known miRNAs and 1 novel miRNA were higher expressed in post-feed milk. As expected, samples richer in viable cells contained more known miRNAs (p = 0.01). Functional analysis of the top 10 most highly expressed known miRNAs showed that they may be potentially involved in crucial roles for the infant, including body fluid balance, thirst, appetite, immune responses, and development. In conclusion, breastmilk is highly rich in miRNA which may play important functions in the breastfed infant and the lactating breast. Milk removal by the infant can influence the total miRNA content of breastmilk, similar to its cell and fat content, but the miRNA composition remains constant
Project description:To investigate the impact transcription that the Spore Forming (SF) Community of bacteria have on the small intestine, B6 mice on a autoclaved diet that were germfree (GF) or colonized with the SF community were investigated. Using laser capture microdissection the intestinal epithelial cells on the villi and the crypts were dissected out and bulk RNA seq was performed.
Project description:We used microarray to determine the differences in hepatic gene expression for diet-induced obese Sprague-Dawley rats consuming different dietary proteins. Proteins of interest included skim milk powder (dairy), casein, and the branched-chain amino acid, leucine. The primary aims of this study were: (i) to compare the effects of diets with protein derived from casein, casein supplemented with leucine, and complete dairy on body composition and insulin sensitivity; and (ii) to determine if there is a synergistic effect of dietary Ca and protein source on body composition and insulin sensitivity. Secondarily, we used microarray analysis to examine the effect of casein, leucine, or complete dairy containing diets on the expression of hepatic genes related to lipid and glucose metabolism. Diet induced obese rats consumed ad libitum, a high fat, high sucrose diet for 8 weeks (n=4). All diets had an energy density of 4.6 kcal/gram and provided 10% of total energy from protein [casein, complete dairy (skim milk powder), or leucine-supplemented casein (7.1% from casein plus 2.9% from leucine)]. The casein treatment was the control diet.
Project description:We used microarray to determine the differences in hepatic gene expression for diet-induced obese Sprague-Dawley rats consuming different dietary proteins. Proteins of interest included skim milk powder (dairy), casein, and the branched-chain amino acid, leucine. The primary aims of this study were: (i) to compare the effects of diets with protein derived from casein, casein supplemented with leucine, and complete dairy on body composition and insulin sensitivity; and (ii) to determine if there is a synergistic effect of dietary Ca and protein source on body composition and insulin sensitivity. Secondarily, we used microarray analysis to examine the effect of casein, leucine, or complete dairy containing diets on the expression of gastrocnemius muscle genes related to lipid and glucose metabolism. Diet induced obese rats consumed ad libitum, a high fat, high sucrose diet for 8 weeks (n=4). All diets had an energy density of 4.6 kcal/gram and provided 10% of total energy from protein [casein, complete dairy (skim milk powder), or leucine-supplemented casein (7.1% from casein plus 2.9% from leucine)]. The casein treatment was the control diet.
Project description:Lactic acid bacteria have been used as starter strains in the production of fermented dairy products for centuries. Lactobacillus acidophilus is a widely recognized probiotic bacteria commonly added to yogurt and used in dietary supplements. In this study, a whole genome microarray was employed to monitor gene expression of L. acidophilus cells propagated in 11% skim milk (SM) during early, mid and late logarithmic phase, and stationary phase. Approximately 21% of 1,864 ORFs were differentially expressed at least in one time point. Genes differentially expressed in SM included several members of the proteolytic enzyme system. Expression of prtP (proteinase precursor) and prtM (maturase) increased over time as well as several peptidases and transport systems. Expression of Opp1 (oligopeptide transport system 1) was highest at 4h, while gene expression of Opp2 increased over time reaching its highest level at 12h, suggesting that the two systems have different specificities. Expression of a two-component regulatory system (2CRS), previously shown to regulate acid tolerance and proteolytic activity, also increased during the early log and early stationary phases of growth. Expression of the genes involved in lactose utilization increased immediately (5 min) upon exposure to milk. The acidification activity, survival under storage conditions, and adhesion to mucin and Caco-2 tissue culture cells of selected mutants containing insertionally inactivated genes differentially expressed in the wild-type strain during growth in milk were examined for any potential links between probiotic properties and bacterial growth and survival in milk. Some of the most interesting genes found to be expressed in milk were correlated with signaling (AI-2) and adherence to mucin and intestinal epithelial cells, in vitro.
Project description:Demand for camel milk (CM) is increasing worldwide, due to its high nutritious value and health benefits. In this study, whole CM powders were produced by spray drying (SD) at six inlet temperatures (190°C - 250°C) and by freeze drying (FD). Physicochemical and functional properties of CM powder proteins were investigated. Both treatments had negative effect on casein solubility, while whey proteins remained soluble and slightly increased its solubility with the extent of MR. The CM powders obtained at higher inlet temperatures demonstrated improved antioxidant activity. Secondary structure of whey proteins did not differ among the samples, while surface hydrophobicity of whey proteins was higher in all SD than in FD samples, suggesting only limited denaturation of camel whey proteins at higher inlet temperatures of drying. Thus, the effects of SD under the conditions applied in our study did not decrease camel whey protein solubility, while drying procedure itself regardless of temperature decreased solubility of camel milk caseins. This study provides useful insights for optimization of CM powder production.