Metabonomic study on 'Kidney-Yang Deficiency syndrome' and intervention effects of Rhizoma Drynariae extracts in rats using ultra performance liquid chromatography coupled with mass spectrometry

This paper was designed to study metabonomic characters of the ‘Kidney-Yang Deficiency syndrome’ induced by high dose of hydrocortisone and the therapeutic effects of Rhizoma Drynariae, classic traditional Chinese medicine (TCM) in treating the syndrome. A urinary metabonomics method based on ultra-performance liquid chromatography coupled with mass spectrometry (UPLC/MS) was developed. The significant difference in metabolic profiling was observed from model group (hydrocortisone-induced group) compared with the pre-dose group (rats before hydrocortisone inducing) by using the principal components analysis (PCA). The time-dependent regression tendency in Rhizoma Drynariae treatment group (hydrocortisone-induced rats followed by being administered with Rhizoma Drynariae ethanol extracts) from day 3 to 15 was obtained, indicating the time-dependent recovery effect of Rhizoma Drynariae on ‘Kidney-Yang Deficiency syndrome’ rats. Some significantly changed metabolites like phenylalanine, phenylacetylglycine, N₂-succinyl-l-ornithine, l-proline, creatinine, hippurate and citrate have been identified. These biochemical changes are related to the disturbance in energy metabolism, amino acid metabolism and gut microflora, which are helpful to further understand the ‘Kidney-Yang Deficiency syndrome’ and the therapeutic mechanism of Rhizoma Drynariae. The work shows that the metabonomics method is a valuable tool for studying the essence of Chinese medicine's syndrome theory and therapeutic effect mechanism of TCM.