Dietary Conjugated Linoleic Acid Alleviates LPS-Induced Mastitis in Mice: A Transcriptomic Study

After 24 h, mammary tissue samples were collected for histopathological examination, measurement of inflammatory cytokine and antioxidant enzyme levels, and transcriptomic analysis.Results The results showed that: 1) Compared with the control group, the CLA‑supplemented groups exhibited varying degrees of pathological damage; however, the 2.0% CLA group displayed more regular alveolar morphology, markedly alleviated interstitial hyperplasia, and essentially restored normal tissue structure. 2) Compared with the control group, the 1.0% and 2.0% CLA groups showed significantly increased levels of interleukin‑1β (IL‑1β), interleukin‑6 (IL‑6), and tumor necrosis factor‑α (TNF‑α) in mammary tissue (P<0.01), along with significantly decreased superoxide dismutase (SOD) activity and total antioxidant capacity (T‑AOC) (P<0.01). 3) Transcriptomic analysis identified 1,321 differentially expressed genes (DEGs) between the control and 2.0% CLA groups.

GO enrichment analysis indicated that these DEGs were mainly involved in T‑cell activation and lymphocyte activation, while KEGG pathway enrichment revealed significant association with nuclear factor‑κB (NF‑κB), TNF, and T‑helper 17 (Th17) inflammatory signaling pathways. Protein‑protein interaction network analysis further identified IL‑6, C‑C motif chemokine ligand 2 (Ccl2), and C‑X‑C motif chemokine receptor 4 (CXCR4) as core target genes.Conclusion These findings suggest that dietary supplementation with 2.0% CLA may alleviate LPS‑induced mammary tissue injury in mice, enhance antioxidant capacity, suppress pro‑inflammatory cytokine expression, and induce regulatory T‑cell differentiation, potentially through the regulation of NF‑κB, TNF, and Th17 inflammatory signaling pathways.