Expression differences of miRNAs and genes on NF-κB pathway between the healthy and the mastitis Chinese Holstein cows

•Variation of miRNAs and genes on NF-κB pathway between healthy and mastitis cows.•The total miRNAs decline and most of the genes expression rise in mastitis cows.•NF-κB pathway is active in mastitis as a result of the decrease of miRNAs.•NF-κB pathway is inactive as the miRNAs enhancing inhibition in healthy cows.•Some miRNAs could be used as new markers for the dairy mastitis prognosing.

In order to discover the variation of microRNAs and genes associated with NF-κB signaling pathway between the healthy and the mastitis Chinese Holstein cows, Illumina Deep Sequencing and qRT-PCR are applied to detect 25 kinds of miRNAs (miR-16, miR-125b, miR-15, miR-29a, miR-23b, miR-146, miR-301a, miR-181b, let-7, miR-30b, miR-21, miR-223, miR-27b, miR-10a, miR-143, etc.) expression levels in blood samples and 14 genes (RelA, RelB, Rel, p105, p100, IκBα, IκBβ, IκBδ, IκBε, IκBζ, Bcl-3, IKKα, IKKβ, IKKγ/NEMO) relative expression levels in nine tissues. The total number of miRNAs is declining, and RelA, Rel, p105, p100, IκBα, IκBβ, IκBδ, IκBζ, Bcl-3, and IKKα expressions are rising in mastitis individuals. So, we suppose that NF-κB pathway is active in mastitis individuals as a result of the decrease inhibition of miRNAs. While in healthy ones, the NF-κB pathway is inactive, because of the miRNAs enhanced inhibition action. However, the specific regulatory mechanism of miRNAs on NF-κB pathway in mastitis Holstein cows needs further investigation. Moreover, due to obvious expression differences, some miRNAs, especially miR-16 and miR-223, may be used as new markers for the dairy mastitis prognosing.