Study highlights anti-inflammatory properties of herbal medicine, Erigeron breviscapus to treat osteoarthritis

In a recent study published in Nutrients, researchers explored using Erigeron breviscapus (EB) as a treatment for osteoarthritis (OA).

Study: Anti-Inflammatory, Analgesic, Functional Improvement, and Chondroprotective Effects of Erigeron breviscapus (Vant.) Hand.-Mazz. Extract in Osteoarthritis: An In Vivo and In Vitro Study. Image Credit: Dragana Gordic/Shutterstock.com

Background

Osteoarthritis, a degenerative bone disorder, causes persistent discomfort, function loss, and joint damage. The worldwide aging trend and a lack of effective medicines are driving up demand for therapy.

The discovery of safe and effective solutions is a public health concern, as existing conservative treatments fail to correct OA’s inflammatory pathology. Erigeron breviscapus is an herbal medication from East Asia with powerful anti-inflammatory qualities that promote disease-fighting benefits across several systems.

However, the existing scientific evidence for EB primarily focuses on cardiovascular diseases and central nervous system disorders, warranting further research.

About the study

In the present study, researchers investigated the therapeutic potential of E. breviscapus for osteoarthritis, specifically the anti-inflammatory-based modulatory effects.

The researchers examined the functional benefits, analgesic effects, and suppression of cartilage breakdown caused by EB among acetic acid-inflicted peripheral-type pain murine animals and monosodium iodoacetate (MIA)-induced osteoarthritis rat models.

They also investigated the inflammation-lowering properties of EB in cartilage tissues and serum in the in vivo settings and lipopolysaccharide (LPS)-induced RAW 264.7 macrophages.

The researchers extracted a powder from dried EB stems and analyzed its components using high-performance-type liquid chromatography (HPLC). They performed the analysis using Sprague-Dawley rats and ICR mice.

The mice received EB extracts (EBE) in 200 mg/kg and 600 mg/kg concentrations, ibuprofen 200 mg/kg, and water as the study control.

After 30 minutes of oral therapy, they administered 0.7% acetic acid in 10 mL/kg concentration intraperitoneally to observe writhing responses 10 minutes later.The MIA-induced OA rat model included five groups: EB extract 300, indomethacin (INDO 3), sham, and control (CON).

They anesthetized the rats with a combination of oxygen and 2.0% isofluorane and intraarticular MIA injections in 40 mg/mL concentration to induce osteoarthritis in the EBE, indomethacin, and control groups.

They disarticulated and macroscopically scored right-side knee joints to assess articular cartilage deterioration.

The researchers drew blood from the abdominal vein to form a blood clot within thirty minutes. The separated serum was tested for interleukin-1 beta (IL-1β) and IL-6 levels. They treated RAW264.7 macrophages with 500 ng/mL LPS and EBE for 24 hours to determine cell viability and EB cytotoxicity.

They extracted ribonucleic acid (RNA) from RAW264.7 cells for quantitative-type real-time polymerase chain reaction (qRT-PCR) analysis.

They used Western blot analysis to determine the protein expression of interleukin-1 beta, interleukin-6, prostaglandin E receptor 2 (Ptger2), nitric oxide synthase 2 (NOS2), matrix metalloproteinase 1 (MMP1), MMP8, MMP13, and glyceraldehyde 3-phosphate dehydrogenase (GAPDH).

Results

In vitro and in vivo, EB significantly reduced functional impairment, pain, and cartilage deterioration associated with osteoarthritis. It also showed dose-dependent inhibition of pro-inflammatory cytokine molecules such as interleukins-1β, 6, MMP- 13, and NOS2 compared to controls.

HPLC analysis identified 7.5 mg/g of chlorogenic acid as the primary anti-inflammatory component of EB. EBE effectively alleviated acetic acid-induced peripheral discomfort in rats, resulting in fewer writhing responses.

EBE treatment dramatically increased the weight-bearing ability of MIA rats, equivalent to INDO3. EBE reduced MIA injection-induced cartilage erosion and recovered cartilage degeneration at a rate similar to INDO3.

The EBE- and INDO3-treated groups dramatically reduced cartilage degradation caused by CON. EBE lowered NO levels, indicating powerful anti-inflammatory effects.

The EBE group saw a dose-dependent drop in blood concentrations of interleukin-1 beta and interleukin-6 compared to the control group, with downregulation effects on MMP-1, MMP-8, MMP-13, PTGER2, IL-1β, IL-6, and NOS2.

At 300 µg/mL, EB extract exhibited minimal cytotoxic effects in RAW264.7 macrophages. DEX1 and EB extract decreased the expression of tumor necrosis factor-alpha (TNF-α), cyclooxygenase 2 (COX-2), IL-1β, IL-6, MMP-1,13, PTGER2, NOS2 messenger RNA (mRNA).

EBE injection reduced the synthesis of pro-inflammatory cytokines such as TNF-α, IL-1β, IL-6, NOS2, MMP-1, and MMP-13, as demonstrated by Western blot imaging. EBE had equivalent anti-inflammatory effects as positive controls for all cytokines.

Conclusions

The study found that Erigeron breviscapus extract improves clinical symptoms of osteoarthritis (OA), such as pain, functional decline, and cartilage breakdown.

It has considerable anti-inflammatory effects on pro-inflammatory mediators such as IL-1β, IL-6, MMP13, and NOS2 that contribute to the inflammatory pathophysiology of OA.

EBE is a possible disease-modifying osteoarthritis drug (DMOAD) candidate that requires more investigation to evaluate its effectiveness in altering the complicated inflammatory pathophysiology of OA.

Future research could explore EBE’s multi-component and multi-target effectiveness, using network pharmacology and bioinformatic approaches to determine the detailed mechanism of action and critical signaling pathways.