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: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: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:We have reported that microRNAs are present in human and bovine milk. But, it is unknown the roles of milk miRNAs. To clarify the roles of milk miRNAs, experimental animal such as rat study would be needed. However, it is unclear whether rat milk also contains miRNAs. Thus, we have employed microarray to show that rat milk also contains miRNAs.
Project description:Human milk is highly recommended for infant during the first six month of life by World Healthy Organisation (WHO). Human milk is not only rich in macro-nutritional components, but also rich in cells and molecules. MicroRNAs are small non-coding RNAs, which enriched in human milk. These molecules are vital in enormous biological and cellular functions including immune system and in response to infections. By using deep sequencing method, 770,374,554 raw reads were generated from all samples (n=26). Then, filter analysis was done to remove 81,091,772 (10.5%), and 689,282,782 clean reads (89.5%) were considered as clean reads, which was retained for the subsequent bioinformatics analysis. Annotation and matching reads to miRBase revealed1780 mature known microRNAs identified in human milk cells and lipids derived from healthy, cold and other infection types mothers. In particular, 1680 known microRNAs were determined in infected mothers (n=14), while 1,606 known microRNAs in healthy mothers (n=12). Of these known microRNAs, 453 microRNAs were differentially expressed (p<0.05) between healthy and infected samples. The majority of the highly expressed miRNAs in all samples, in particular top 20 microRNAs, were also differentially expressed between healthy and infections. Further, 592 novel mature microRNA sequences were predicted, with only 65,878 total reads. Amongst the total reads of the novel microRNAs, top 20 novel miRNAs were found to contributed in 73.3% (total reads 48,295) of the total reads (65,878).
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:Milk can mediate maternal-neonatal signal transmission by the bioactive component-extracellular vesicles (EVs), which select specific types of miRNA to encapsulate. The miRNA profiling of sheep milk EVs was characterized by sequencing and compared with that of cow milk. Sheep milk EVs contained various small RNAs, including tRNA, Cis-regulatory element, rRNA, snRNA, other Rfam RNA, and miRNA, which held about 36% of all the small RNAs. Totally 84 types of miRNAs were annotated with Ovis aries by miRBase (version 22.0) in sheep milk EVs, with 75 shared types of miRNAs in all samples. Fourteen sheep milk EV-miRNAs in the top 20, occupying 98% of the total expression, were immune-related.
Project description:Given that different diets could alter cow milk yield and composition, the effects of different feed formula on milk extracellular vesicle (EV) miRNAs were detected. Cow milk EVs contained various small RNAs, including miRNAs, snRNAs, tiRNAs, Cis-regulatory elements, and piRNAs. Two hundred and seventy-six known bos taurus miRNAs were identified by sequencing in bovine milk EVs. There were 13 immune-related miRNAs in the top 20 miRNAs in milk EVs. Nine differently expressed known miRNAs were detected in responding to different feed formulations. Cow milk EVs are abundant of small RNAs, especially miRNAs, which might be closely related to the development of maternal mammary gland and neonatal immune maturity.