The antioxidant effect of triptolide contributes to the therapy in a collagen-induced arthritis rat model

ABSTRACT

Background

As a chronic autoimmune disease, rheumatoid arthritis (RA) is related to oxidative stress, which may lead to the occurrence and persistence of inflammation in RA. The purpose of this study is to evaluate the potential antioxidant effect of triptolide in collagen-induced arthritis (CIA) rat model.

Methods

We examined the severity of arthritis, levels of local and systemic oxidative stress, periarticular bone erosion and weight of organs in CIA rats treated with triptolide.

Results

We found that triptolide decreased the paw thickness and clinical arthritis score, significantly. The mRNA expression and activity of myeloperoxidase and inducible nitric oxide synthase were remarkably decreased in the paws of the CIA rats after triptolide treatment. Triptolide significantly inhibited the levels of nitrite and nitrate in serum, as well as the urinary level of dityrosine. Triptolide treatment also markedly increased bone volume of tibia, but suppressed epiphyseal plate thickness of both femur and tibia. In addition, there was no significant difference in the weight of organs after the therapy, except decreased spleen weight.

Conclusions

These results suggested that the local and systemic oxidative stress was enhanced in the CIA rats and the therapeutic dose of triptolide had a definite antioxidant effect.

KEYWORDS:

• Triptolide
• rheumatoid arthritis
• rat
• collagen induced arthritis
• local oxidative stress
• systemic oxidative stress
• bone destruction
• relative weight of organ

Acknowledgements

The authors are grateful to Dr. Jie Wu for assisting in graphics (School of Pharmacy, Jinan University).

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability statement

All data analyzed during this study are available from the corresponding author on request.

Additional information

Funding

This study was supported by One Hundred Youngsters Project of Guangdong University of Technology [grant number: 1182-220413715], Science and Technology Innovation Training Program [grant number: xj202011845178] and City & University Cooperation Research Project of Nanchong [grant number: 19SXHZ0177].