# A proteomics-based study on the mechanisms of Terminalia chebula Retz processed Aconitum kusnezoffii Reichb against rheumatoid arthritis and its cardiotoxicity reduction

## TL;DR

This study uses proteomics to explore how processing Aconitum kusnezoffii with Terminalia chebula reduces its toxicity and maintains its effectiveness in treating rheumatoid arthritis.

## Contribution

The study introduces a multidimensional proteomics approach to elucidate the detoxification and efficacy mechanisms of a processed herbal formulation in a disease model.

## Key findings

- HC reduced foot swelling and arthritis index in CIA rats while lowering inflammatory markers like TNF-α and IL-6.
- Proteomic analysis showed HC downregulated Ctsk, Acp5, and Casp3, which are linked to bone erosion and joint damage.
- HC reduced cardiotoxicity by lowering oxidative stress and apoptosis markers compared to raw Caowu.

## Abstract

Although the efficacy of Aconitum kusnezoffii Reichb (Caowu) in treating rheumatoid arthritis is well-established, its severe toxic side effects have attracted widespread attention from researchers both domestically and internationally. Processing is an important method for reducing the toxicity of Caowu and ensuring its safe clinical application, with the processing of Caowu using the Terminalia chebula Retz (Hezi) decoction method being a distinctive approach in Mongolian medicine. The majority of current studies on HC are still conducted in animal models under normal physiological conditions, failing to adequately account for the impact of pathological states on its efficacy and toxicity. Moreover, the material basis underlying its effects and the molecular mechanisms through which processing reduces toxicity while preserving therapeutic efficacy remain unclear.

This study employs proteomics to uncover changes in toxicity- and efficacy-related proteins during the in vivo action of Hezi Processed Caowu (HC), thereby exploring the molecular mechanisms behind its ‘‘toxicity reduction while efficacy retention’’.

Using LC–MS/MS technology, based on the Collagen- Induced Arthritis (CIA) rat model, we combined in vivo and in vitro chemical composition analysis, in vivo pharmacology/toxicology, proteomics, molecular docking, and other research methods to explore its molecular mechanism.

Using UPLC-Q-Orbitrap-MS/MS technology, 43 compounds were identified in the positive ion mode for HC. After administration of HC, 24 parent compounds were detected in plasma and 25 parent components were detected in the heart. A CIA rat model was established to evaluate the anti-RA (Rheumatoid Arthritis) pharmacological effects of HC. It was found that HC could reduce foot swelling in CIA rats, lower the arthritis index, and decrease the secretion of MMP-2, MMP-3, TNF-α, and IL-6. Proteomic analysis revealed that, compared with the CIA group, administration of HC significantly downregulated the protein expression of Ctsk, Acp5, and Casp3. Molecular docking was employed to simulate the spatial conformation between the core differentially expressed target proteins and the blood-absorbed bioactive components of the HC. The highest docking scores were observed between Ctsk and benzoylaconitine, Casp3 and aconitine, as well as Acp5 and ellagic acid. After long-term treatment of CIA rats with raw Caowu (RC) and HC, histopathological examination and electrocardiogram (ECG) detection indicated significant cardiotoxicity in the RC group, which was ameliorated by HC group. Subsequent biochemical analysis showed that, compared to the raw aconite group, the levels of AST, ALP, LDH, CK, CK-MB, TP, and TBA were reduced in the HC group. Proteomic studies further demonstrated that the expression of Kng1 and Sod1 was downregulated in the HC group compared to the RC group. Western blot analysis confirmed that Nrf2, Kng1, and Sod1 were highly expressed in the RC group, whereas their expression was reduced in HC group. Additionally, compared with the RC group, HC decreased the levels of Casp3 and Bax, while increasing the expression of Bcl2. Further analysis using molecular docking technology validated the spatial conformation of differentially expressed core target proteins with cardiac active components. Among these, Nrf2 had the highest docking score with benzoylmesaconine, Kng1 had the highest docking score with chasmanine, and Sod1 had the highest docking score with benzoylaconitine. Casp3 had the highest docking score with aconitine, Bax had the highest docking score with senbusine A, and Bcl2 had the highest docking score with mesaconine.

HC exerts its anti-RA effects by prolonging the retention time of anti-inflammatory components in the body, reducing the expression of Ctsk, Acp5, and Casp3 proteins, and inhibiting bone erosion and joint damage; it also reduces cardiac toxicity by reducing oxidative stress and protecting against apoptosis, thereby forming a multidimensional detoxification mechanism. This study focused on the anti-inflammatory activity of HC, integrating blood component analysis, cardiac tissue distribution detection, and disease model-driven synovial and cardiac proteomics analysis to scientifically elucidate the detoxification and efficacy principles of HC, providing new strategies for comprehensive research on detoxification and efficacy in the preparation of toxic herbs for ethnic minorities.

The online version contains supplementary material available at 10.1186/s13020-025-01306-8.