A comparative metabolomics study on dried and processed Rehmannia Radix

Area of Science:

• Pharmacology
• Metabolomics
• Traditional Chinese Medicine (TCM)

Background:

• The efficacy of Rehmannia Radix varies with processing.
• Traditional methods struggle to explain processing-induced property changes.
• Understanding these changes is crucial for TCM applications.

Purpose of the Study:

• To investigate how processing influences Rehmannia Radix properties.
• To analyze metabolic changes in the body after administering dried (RR) and processed (PR) Rehmannia Radix.
• To clarify differences in properties and efficacies between RR and PR.

Main Methods:

• Utilized a metabolomics approach to study RR and PR.
• Employed principal component analysis and orthogonal partial least-squares discriminant analysis for property evaluation.
• Identified potential biomarkers and established metabolic networks.

Main Results:

• RR demonstrated cold properties and a hypolipidaemic effect via nicotinate/nicotinamide metabolism.
• PR exhibited hot properties, supporting tonic effects and reproductive function through specific metabolic pathways.
• Metabolomics successfully differentiated the properties of RR and PR.

Conclusions:

• Metabolomics, particularly UHPLC-QTOF-MS, is a powerful tool for characterizing TCM properties.
• Processing significantly alters Rehmannia Radix, leading to distinct pharmacological effects.
• This study provides a scientific basis for understanding Rehmannia Radix processing in TCM.