Bailing capsule alleviates autoimmune thyroiditis regulating peroxisome proliferator-activated receptor signaling...

To investigate the efficacy and potential mechanism of Bailing capsule (, BL) anti-autoimmune thyroiditis (AIT).

Based on the AIT rat model, the effect of BL in alleviating AIT was evaluated by detecting serum thyroid index free triiodothyronine (FT3), free thyroxine (FT4), thyroid-stimulating hormone (TSH), thyroglobulin antibody (TGAb), thyroid peroxidase antibody (TPOAb), and inflammatory factors Interferon-gamma (IFN-γ), Interleukin-4, -10, and -12 (IL-4, IL-10, and IL-12) as well as thyroid tissue Hematoxylin-eosin (HE) staining and ultrastructure observation. The mechanism of BL was explored by combining transcriptome and proteome analysis, and further verified by Western blot (WB).

BL effectively reduced serum FT3, FT4, TGAb, and TPOAb levels in AIT rats, restored TSH balance, inhibited the release of pro-inflammatory cytokines IFN-γ and IL-12, promoted the production of anti-inflammatory cytokines IL-4 and IL-10, and significantly reduced IFN-γ/IL-4 and IL-12/IL-10, improved thyroid follicular structure, and protected thyroid tissue from injury. Kyoto Encyclopedia of Genes and Genomes and protein interaction network analysis showed that BL affected the expression of fatty acid-binding protein 4, acyl-CoA synthetase long-chain family member 1, and acyl-CoA dehydrogenase long chain to regulate the peroxisome proliferator-activated receptor signaling pathway, thereby inhibiting the fatty acid metabolism and the inflammatory state of AIT rats.

BL could effectively reduce thyroid inflammation in AIT model rats. The possible BL mechanism was to regulate the peroxisome proliferator-activated receptor signaling pathway and inhibit fatty acid metabolism. This study suggested that BL has the potential to be used in clinical treatment of AIT.