Project description:In dairy cows, milk production and composition are affected by numerous factors, including diet. Milk is the body fluid with the highest RNA concentration, including numerous microRNA. These microRNA presence in the different milk compartments is still poorly documented and the effect of feed restriction on milk miRNome has not been described yet. The aim of this study was to describe the effects of feed restrictions of different intensitizes on milk compartment miRNome composition. Two feed restriction trials were performed on lactating dairy cows, one of high intensity and one of moderate intensity. 2 896 mature microRNA were identified in milk, including 1 493 that were already known in bovine specie. Among the 1 095 miRNA that were abundant enough to be informative, 10% were exclusive to one milk compartment and the abundance of 155 varied between compartments, revealing a specific miRNome for each milk fraction. Feed restriction affected differently these miRNome, with microRNA in whole milk and milk extracellular vesicles being the most affected and microRNA in fat globules and exfoliated mammary epithelial cells being relatively or completely unaffected. Target prediction of known microRNA that varied under feed restriction reflected modification of some key pathways for lactation related to milk fat and protein metabolisms, cell cycle and stress responses. These findings open up opportunities for future research on the use of milk miRNA as biomarkers of energy status in dairy cows.
Project description:The MUCUS clinical trial (https://clinicaltrials.gov: NCT01433471) was established to investigate the effect of Trichuris suis ova on ulcerative colitis patients.
Project description:Studies of normal human mammary gland development and function have mostly relied on cell culture, limited surgical specimens, and rodent models. Although RNA extracted from human milk has been used to assay the mammary transcriptome non-invasively, the transcriptome derived from the milk fat layer has not been compared with the mammary-derived transcriptome nor have sources of RNA been quantified in milk. In this study the effects of milk collection and processing on RNA quality and origin were assessed in humans and rhesus macaques. Total RNA in milk was quantitated in acridine orange-stained milk using an automated whole slide scanner and custom-built Globulator software. Total RNA extracted from milk fat, cells in milk, and mammary biopsies of lactating rhesus macaques were compared using RNA sequencing and analysis. Compared with human milk, milk from macaques contained similar amounts of RNA-containing cytoplasmic crescents, but more cells. Total RNA extracted from milk fractions was also evaluated for factors that affect RNA quality. Degradation of RNA extracted from human milk fat was positively correlated with geographic distance from collection site, storage time, and sample type. There were no differences in RNA degradation in macaque milk collected after 10 min or 4 hr accumulation, suggesting that degradation of RNA extracted from milk fat may not occur in the mammary gland. Using RNA-Seq, RNA extracted from macaque milk fat and cells in milk more accurately represented RNA from mammary epithelial cells (cells that produce milk) than did RNA from mammary tissue. Mammary epithelium-specific transcripts were more abundant in macaque milk fat whereas adipose or stroma-specific transcripts were more abundant in mammary tissue. Functional analyses confirmed the validity of milk as a source of RNA from mammary epithelial cells. Analysis of highly abundant putative microRNAs in macaque milk fat revealed a potentially novel non-coding RNA species that is conserved in humans. RNA extracted from the milk fat during lactation accurately portrayed the RNA profile of milk-producing mammary epithelial cells. However, this sample type clearly requires protocols that minimize RNA degradation. Transcript profiles from milk cells, milk fat, and mammary tissue from 6 lactating rhesus macaques at 30 and 90 days lactation; 34 samples run in triplicate
Project description:Studies of normal human mammary gland development and function have mostly relied on cell culture, limited surgical specimens, and rodent models. Although RNA extracted from human milk has been used to assay the mammary transcriptome non-invasively, the transcriptome derived from the milk fat layer has not been compared with the mammary-derived transcriptome nor have sources of RNA been quantified in milk. In this study the effects of milk collection and processing on RNA quality and origin were assessed in humans and rhesus macaques. Total RNA in milk was quantitated in acridine orange-stained milk using an automated whole slide scanner and custom-built Globulator software. Total RNA extracted from milk fat, cells in milk, and mammary biopsies of lactating rhesus macaques were compared using RNA sequencing and analysis. Compared with human milk, milk from macaques contained similar amounts of RNA-containing cytoplasmic crescents, but more cells. Total RNA extracted from milk fractions was also evaluated for factors that affect RNA quality. Degradation of RNA extracted from human milk fat was positively correlated with geographic distance from collection site, storage time, and sample type. There were no differences in RNA degradation in macaque milk collected after 10 min or 4 hr accumulation, suggesting that degradation of RNA extracted from milk fat may not occur in the mammary gland. Using RNA-Seq, RNA extracted from macaque milk fat and cells in milk more accurately represented RNA from mammary epithelial cells (cells that produce milk) than did RNA from mammary tissue. Mammary epithelium-specific transcripts were more abundant in macaque milk fat whereas adipose or stroma-specific transcripts were more abundant in mammary tissue. Functional analyses confirmed the validity of milk as a source of RNA from mammary epithelial cells. Analysis of highly abundant putative microRNAs in macaque milk fat revealed a potentially novel non-coding RNA species that is conserved in humans. RNA extracted from the milk fat during lactation accurately portrayed the RNA profile of milk-producing mammary epithelial cells. However, this sample type clearly requires protocols that minimize RNA degradation.
Project description:Milk is an indispensable source of infant nutrition in all mammals, made up of complex constituents needed for infant nourishment and immunity. Comparison of miRNA profiles between infected and non-infected/control Holstein cattle could provide important information on the differences in composition of milk at the level of miRNA, if any, and broaden our perspective and understanding of the effect of pathology on cellular compositions and functions. In the present study we therefore analyzed the expression profiles of bovine milk exosomal miRNAs during S. uberis infection and identified 328 known miRNAs and 82 high-confidence miRNA candidates by deep sequencing. The top 10 miRNAs in both control and infected replicates accounted for approximately 80% of total counts, which were predicted to target 605 genes using two computational approaches. In addition, 15 significantly differentially expressed miRNAs were identified between control and infected replicates during S. uberis infection, and a total of 1,852 unique genes were predicted to be targeted by these miRNAs. Ingenuity Canonical Pathways and Diseases and Biological Function analyses using IPA indicated that the identified miRNAs targets mainly enriched in regulating the innate and adaptive immune responses in newborns, as well as infant growth and development. The characterization of these miRNAs could contribute to a better understanding of the molecular mechanisms involved in lactation physiology and milk imparted immune function in the dairy cattle.
Project description:Breast milk is the primary source of nutrition for newborns, and rich in immunological components. microRNAs (miRNAs), a well-defined group of non-coding small RNAs, are present in various body fluids (such as breast milk), which are selectively packaged inside the exosomes, a type of membrane vesicles, secreted by most cell types. These exosomal miRNAs could be actively delivered into recipient cells, and regulate target gene expression and recipient cell function. We present the lactation-related miRNA expression profiles in porcine milk exosomes across entire lactation period in pig industry (newborn to 28 days after birth) using deep sequencing technology. We found that the immune-related miRNAs are presented and enriched in breast milk exosomes, and generally resistant to relatively harsh conditions. Notably, these exosomal miRNAs exhibited the higher abundances in the colostrum (newborn to 3 days after birth) than that in the mature milk (7 to 28 days after birth), as well as in the serum of colostrum-feeding piglets compared with the only mature milk-feeding piglets. These immune-related miRNAs-loaded exosomes in breast milk may be transferred into the infant body via the digestive tract. These observations are prelude to the in-depth investigations of the essential roles of the breast milk in the development of the infant’s immune system.
Project description:Human milk extracellular vesicles (EVs) are crucial mother-to-baby messengers that transfer biological signals. These EVs are reported to survive digestion and transport across the intestine. The mechanisms of interaction between human milk EVs and the intestinal mucosa, including epithelial uptake remain unclear. Here, we studied the interaction of human milk EVs with the gut barrier components, including intestinal biofluids, enzymes, mucus and epithelium. Additionally, we probed the endocytic mechanisms mediating the EV intestinal uptake. Finally, using proteomic analysis, we determined the existence and identification of proteins enriched in the EV fraction transported across the intestinal epithelium. We show that human milk EVs are largely stable in the biochemical gut barriers and demonstrate high mucus diffusivity. EVs show a high level of epithelial cell uptake (~70%), and efficient transport across Caco-2 monolayers. Whilst cell uptake of EVs was mediated by multiple routes, none of the pathway-specific inhibitors inhibited their epithelial translocation. Proteomic analysis of EVs transported across Caco-2 monolayers identified 14 enriched EV proteins that may facilitate intestinal transport. These findings significantly expand our understanding of the interactions between human milk EVs and the gut barriers, including their intestinal uptake.
Project description:Antibiotic use is a risk factor for development of inflammatory bowel diseases (IBDs). IBDs are characterized by a damaged mucus layer, which does not properly separate the host intestinal epithelium from the microbiota. Here, we hypothesized that antibiotics might affect the integrity of the mucus barrier. By systematically determining the effects of different antibiotics on mucus layer penetrability we found that oral antibiotic treatment led to breakdown of the mucus barrier and penetration of bacteria into the mucus layer. Using fecal microbiota transplant, RNA sequencing followed by machine learning and ex vivo mucus secretion measurements, we determined that antibiotic treatment induces ER stress and inhibits colonic mucus secretion in a microbiota-independent manner. This mucus secretion flaw led to penetration of bacteria into the colonic mucus layer, translocation of microbial antigens into circulation and exacerbation of ulcerations in a mouse model of IBD. Thus, antibiotic use might predispose to development of intestinal inflammation by impeding mucus production.
Project description:Antibiotic use is a risk factor for development of inflammatory bowel diseases (IBDs). IBDs are characterized by a damaged mucus layer, which does not properly separate the host intestinal epithelium from the microbiota. Here, we hypothesized that antibiotics might affect the integrity of the mucus barrier. By systematically determining the effects of different antibiotics on mucus layer penetrability we found that oral antibiotic treatment led to breakdown of the mucus barrier and penetration of bacteria into the mucus layer. Using fecal microbiota transplant, RNA sequencing followed by machine learning and ex vivo mucus secretion measurements, we determined that antibiotic treatment induces ER stress and inhibits colonic mucus secretion in a microbiota-independent manner. This mucus secretion flaw led to penetration of bacteria into the colonic mucus layer, translocation of microbial antigens into circulation and exacerbation of ulcerations in a mouse model of IBD. Thus, antibiotic use might predispose to development of intestinal inflammation by impeding mucus production.