Objective: To investigate the efficacy and potential mechanism of Bailing capsule (, BL) anti-autoimmune thyroiditis (AIT).
Methods: 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).
Results: 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.
Conclusions: 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.
Keywords: Bailing capsule; cordyceps; fatty acid; peroxisome proliferator-activated receptors; thyroiditis, autoimmune.