Anti-arthritic effect of total anthraquinone from Polygonum cuspidatum on type II collagen-induced arthritis in rats

Feng Wang,Hong Zhao,Yan-hong Qiao,Hui-min Niu

doi:10.4314/tjpr.v16i10.20

Abstract

Purpose: To study the anti-arthritic effect of total anthraquinone from Polygonum cuspidatum (TAPC) on type II collagen-induced arthritis (CIA) in rats, and to investigate the underlying mechanism(s).Methods: CIA rats were prepared and treated orally with TAPC at doses of 50, 100 and 200 mg/kg/day, for 24 days. Paw volume and arthritis score were measured prior to TAPC treatment, and subsequently at 3-day intervals on days 3, 6, 9, 12, 15, 18, 21 and 24. Serum levels of TNF-α, IL-6 and IL-17 were determined by enzyme-linked immunosorbent assay (ELISA), while synovial tissue TNF-α, IL-6 and IL-17mRNA expressions were assayed by real time-polymerase chain reaction (RT-PCR). Thymus and spleen indices were also determined.Results: TAPC (50, 100 and 200 mg/kg) significantly alleviated paw swelling (p < 0.05), arthritis scores (p < 0.05) and thymus and spleen indices (p < 0.05) of CIA rats, when compared with the control rats. In addition, TAPC significantly decreased serum levels of the pro-inflammatory cytokines TNF-α, IL-6 and IL-17 (p < 0.01); and down-regulated their mRNA expressions in synovial tissues (p < 0.01).Conclusion: These results suggest that TAPC exerts good anti-arthritic activity in rats, most probably via suppression of inflammatory responses.Keywords: Polygonum cuspidatum, Anthraquinone, Type II collagen-induced arthritis, Pro-inflammatory cytokines

Highlights

Rheumatoidarthritis (RA) is a common destructive chronic systemic autoimmune disease of the joints [1,2]
total anthraquinone from Polygonum cuspidatum (TAPC) treatment at doses of 50, 100 and 200 mg/kg significantly and dose-dependently decreased the arthritis scores (p < 0.01) as well as paw swelling (p < 0.05, p < 0.01 and p < 0.01, respectively) in collagen-induced arthritis (CIA) rats, when compared with untreated CIA rats. All these results suggested that TAPC might possess notable therapeutic effect for treating RA
The present results demonstrated that TTAPC treatment (50, 100 and 200 mg/kg) significantly and dosedependently down-regulated the expressions of the mRNA expressions of tumor necrosis factor (TNF)-α, IL-6 and IL-17 mRNAs in synovial tissues (p < 0.01), when compared with the control rats

Summary

INTRODUCTION

Rheumatoidarthritis (RA) is a common destructive chronic systemic autoimmune disease of the joints [1,2]. Previous reports indicated that extracts of P. cuspidatum exerted significant anti-arthritic effect in rats, which effect was thought to be due to their anthraquinone contents [14]. The present investigation was aimed at investigating the antiarthritic effect of total anthraquinones from P. cuspidatum (TAPC) against type II collageninduced arthritis (CIA) in rats, and the mechanism(s) involved. An arthritic rat model was established using type II collagen (CII). After 20 days of the initial CII immunization, the rats were orally administered saline, MTX and Determination of TNF-α, IL-6 and IL-17 mRNA expressions in synovial tissues. Synovial tissue samples were homogenized in liquid nitrogen and the total RNA was isolated by RNAiso Plus kits (TaKaRa, Tokyo, Japan). The relative mRNA expressions of TNF-α, IL-6 and IL-17 in synovial tissues were determined by 2−ΔΔCT relative quantitative analysis. SPSS software (SPSS for Windows 19.0; IBM Corp., Armonk, NY, USA) was used for the analysis, and statistical significance was set at p < 0.05

RESULTS

DISCUSSION

Conflict of Interest