Inhibitory Effect on Nitric Oxide Production and Free Radical Scavenging Activity of Thai Medicinal Plants in Osteoarthritic Knee Treatment
Areeya Anuthakoengkun MSc*, Arunporn Itharat PhD**,***
Affiliation : * Master student of sciences (Applied Thai Traditional Medicine), Faculty of Medicine, Thammasat University, Pathumthani, Thailand ** Department of Applied Thai Traditional Medicine, Faculty of Medicine, Thammasat University, Pathumthani, Thailand *** Center of Excellence on Applied Thai Traditional Medicine Research (CEATMR), Faculty of Medicine, Thammasat University, Pathumthani, Thailand
Background : Thai medicine plants used for Osteoarthritis of knee (OA) treatment consist of twelve plants such as Crinum
asiaticum, Cleome viscosa, Drypetes roxburghii, Piper longum, Piper nigrum, Plumbago indica, Alpinia galanga, Curcuma
aromatica, Globba malaccensis, Zingiber montanum, Zingiber officinale and Zingiber zerumbet. They showed high frequency
in OA formula.
Objective : To investigate inhibitory effect on LPS-induced nitric oxide (NO) release from RAW 264.7 cell and free radical
scavenging activity using DPPH assay of these ethanolic plant extracts.
Material and Method: Plant materials were extracted by maceration in 95% ethanol. Anti-inflammatory activity were tested
on LPS-induced NO production. Free radical scavenging activity was performed by DPPH assay.
Results : All of ethanolic extracts exhibited potent inhibitory effect on NO release. The ethanolic extract of Z. zerumbet
exhibited the highest inhibitory effect followed by Z. montanum and G. malaccensis, respectively. Except A. galanga and C.
viscosa, all extracts possessed more influential than indomethacin (IC50 = 20.32+3.23 μg/ml), a positive control. The
investigation on antioxidant activity suggested that the ethanolic extracts of D. roxburghii, Z. officinale, Z. montanum, C.
aromatic, A. galanga, P. indica, G. malaccensis, P. nigrum exhibited antioxidant activity. By means of D. roxburghii had the
highest electron donating activity, followed by Z. officinale. Moreover, both extracts were more effective than BHT, a positive
control (EC50 = 14.04+1.95 μg/ml).
Conclusion : Thai medicinal plants had anti-inflammatory activity and could inhibit destruction of articular cartilage that
corresponded to the traditional medicine and supported using these medicinal plants for OA treatment.
Keywords : Osteoarthritis of knee, Thai medicinal plants, Inhibitory effect on nitric oxide release, Antioxidant activity
