Xiao-Luo-Wan treats propylthiouracil-induced goiter with hypothyroidism in rats through the PI3K-AKT/RAS pathways based on UPLC/MS and network pharmacology.

ETHNOPHARMACOLOGICAL RELEVANCE

Goiter with hypothyroidism occurs in several thyroid diseases. Xiao-Luo-Wan (XLW), which contains Scrophularia ningpoensis Hemsl., Fritillaria thunbergii Miq. and Ostrea gigas Thunberg, has been used as an effective Chinese medicine for the treatment of goiters in China for hundreds of years. Based on clinical observations and experimental studies, XLW also exerts a certain effect on hypothyroidism. However, the therapeutic mechanism of XLW remains unclear.

AIM OF THE STUDY

The present study aimed to investigate the therapeutic effect of XLW on propylthiouracil (PTU)-induced goiter with hypothyroidism in rats and to uncover the underlying molecular mechanism using ultra high-performance liquid chromatography-mass spectrometry (UPLC/MS), network pharmacology, and molecular docking simulations.

MATERIALS AND METHODS

After successful modeling, the remaining rats were randomly divided into a model group, an Euthyrox group, an XLW group, and a control group. The corresponding drugs were given by gavage for four consecutive weeks. The growth status was monitored, the relative thyroid weight was calculated, and the total serum T3, T4, and TSH content were detected. Hematoxylin-eosin (H&E) staining was used to observe the pathological changes in the thyroid glands. The chemical components of the XLW were identified by UPLC/MS and the putative targets of XLW were predicted using multiple databases. We performed network pharmacology based on the intersection of goiter/hypothyroidism-related targets and XLW targets. Then, we performed KEGG pathway enrichment analysis, and key targets were further screened using protein-protein interaction (PPI) networks. Finally, molecular docking was used to predict the binding ability of XLW identified components and the key targets.

RESULTS

XLW significantly increased the levels of T3 and T4, and reduced TSH, increased body weight, and decreased swollen thyroid glands in PTU-induced rats. XLW promoted the morphological recovery of thyroid follicles and epithelial cells. Twenty-one main chemical components of XLW were identified using UPLC/MS. 270 potential gene targets of XLW and 717 known targets of goiter/hypothyroidism disease were obtained by searching the Traditional Chinese Medicine Systems Pharmacology Database (TCMSP), Swiss Target Prediction, and UniProt databases. A total of 83 KEGG pathways were enriched with phosphatidylinositol 3-kinase-protein kinase B (PI3K-AKT) and RAS signaling pathways. PPI analysis revealed nine key targets of kinase-protein kinase B (AKT) 1, interleukin (IL) 6, vascular endothelial growth factor A (VEGFA), tumor necrosis factor (TNF), glyceraldehyde 3-phosphate dehydrogenase (GAPDH), epidermal growth factor receptor (EGFR), GTPase HRas (HRAS), matrix metalloproteinase (MMP) 9, and heat shock protein 90 alpha family class A member 1 (HSP90AA1). Molecular docking verified which drug components had good binding ability to key targets (all ≤5 kcal/mol).

CONCLUSION

For PTU-induced goiter with hypothyroidism in rats, XLW improves thyroid function, reduces goiter, increases body weight, and promotes the recovery of thyroid follicles and epithelial cells. The underlying molecular mechanism suggests that XLW may regulate thyroid hormone signaling by regulating the PI3K-AKT, RAS, and other signaling pathways. This study provides a pharmacological and biological basis for using XLW to treat goiter with hypothyroidism.