Expression Characteristics of microRNA in Pig Umbilical Venous Blood and Umbilical Arterial Blood

SIMPLE SUMMARY: Umbilical cord blood is an important biological resource for research on fetal development and treatment of related diseases. To further explore the biological functions of umbilical cord blood, we sequenced the small RNAs in porcine umbilical venous blood and umbilical arterial blood and analyzed them through two differential expression analysis methods. Through comparative analysis, it is found that highly expressed miRNAs in umbilical venous blood and umbilical artery blood perform similar functions, but there may be differences in immunity and angiogenesis. Because miRNAs are highly conserved and have the ability to transmit across species, they have great potential in the treatment of human-related diseases. Further analysis shows that cord venous blood miRNA may be helpful in the treatment of muscle-related diseases, while cord arterial blood miRNA may be beneficial in the treatment of liver- and brain-related diseases. This research helps to analyze the biological functions of cord blood miRNA and provides a reference for the development and application of porcine cord blood miRNA-related products. At the same time, it provides new insights for the further development of value-added products in the animal husbandry industry and the treatment of human diseases. ABSTRACT: As the medium of material exchange between mother and fetus, umbilical cord blood is closely connected with fetal development. microRNA (miRNA) has a wide range of biological functions and has high flow characteristics. Small RNA sequencing of pig umbilical venous blood (UVB) and umbilical arterial blood (UAB) revealed that a total of 302 miRNAs were identified, and 106 and 22 miRNAs were specifically expressed in the UVB and UAB, respectively. Using the two methods of differential expression multiple and differential expression percentage, it is found that only 35% of the highly expressed miRNAs in the UVB by the two analysis modes overlap, but 56.25% of the enriched signal pathways are the same. Only 20% of the highly expressed miRNAs in the UAB overlap, but 62.07% of the signal pathways are the same. Further analysis revealed that miR-423 can be used as a characteristic miRNA of UVB and has the potential to treat muscle-related diseases. miR-122-5p can be used as a characteristic miRNA of UAB and may help to improve liver- and brain-related diseases. In summary, these results enrich understanding of miRNA in mother–fetal communication and provide a reference for the development and application of porcine cord blood products.