Liu Zhihong, Xie Yuchun, Guo Juntao, Su Xin, Zhao Cun, Zhang Chongyan, Qin Qing, Dai Dongliang, Tuo Yanan, Li Zongyuan, Wu Danni, Li Jinquan
College of Animal Science, Inner Mongolia Agricultural University, Hohhot 010018, Inner Mongolia, China.
Key Laboratory of Animal Genetics, Breeding and Reproduction, Hohhot 010018, Inner Mongolia Autonomous Region, China.
Arch Anim Breed. 2022 Jan 26;65(1):37-46. doi: 10.5194/aab-65-37-2022. eCollection 2022.
Milk exosomal microRNAs (miRNAs) are important for postnatal growth and immune system maturation in newborn mammals. The functional hypothesis of milk exosomal miRNAs and their potential bioavailability in milk to newborn mammals were investigated. Briefly, 37 exosomal miRNAs were upregulated compared to miRNAs found outside the exosomes. Among these miRNAs, ssc-miR-193a-3p expression was upregulated 1467.35 times, while ssc-miR-423-5p, ssc-miR-551a, ssc-miR-138, ssc-miR-1 and ssc-miR-124a were highly concentrated and upregulated 13.58-30.06 times. Moreover, these miRNAs appeared to be relevant for cell development and basic physiological processes of the immune system. Following the analysis of target gene prediction and related signalling pathways, 9262 target genes were mainly concentrated in three signalling pathways: metabolic pathways, pathways in cancer, and phosphatidylinositol 3-kinase/protein kinase B (PI3K/Akt) signalling pathways. Among 9262 target genes, more than 20 miRNAs were enriched in exosomes, such as methyl CpG binding protein 2 (MECP2) and glycogen synthase 1 (GYS1). After determining the miRNA localization-, distribution- and function-related metabolism, we found that these exosomes were specifically concentrated miRNA target genes and they were interrelated with cell development and basic cell functions, such as metabolism and immunity. It is speculated that miRNAs in milk can influence offspring via milk exosomes.
乳外泌体微小RNA（miRNA）对新生哺乳动物的出生后生长和免疫系统成熟很重要。我们研究了乳外泌体miRNA的功能假说及其在乳汁中对新生哺乳动物的潜在生物利用度。简而言之，与外泌体之外发现的miRNA相比，有37种外泌体miRNA上调。在这些miRNA中，ssc-miR-193a-3p的表达上调了1467.35倍，而ssc-miR-423-5p、ssc-miR-551a、ssc-miR-138、ssc-miR-1和ssc-miR-124a高度富集且上调了13.58至30.06倍。此外，这些miRNA似乎与细胞发育和免疫系统的基本生理过程相关。在对靶基因预测和相关信号通路进行分析后，9262个靶基因主要集中在三个信号通路：代谢通路、癌症通路和磷脂酰肌醇3-激酶/蛋白激酶B（PI3K/Akt）信号通路。在9262个靶基因中，有20多种miRNA在外泌体中富集，如甲基CpG结合蛋白2（MECP2）和糖原合酶1（GYS1）。在确定了与miRNA定位、分布和功能相关的代谢后，我们发现这些外泌体特异性富集了miRNA靶基因，并且它们与细胞发育和基本细胞功能（如代谢和免疫）相互关联。据推测，乳汁中的miRNA可通过乳外泌体影响后代。
