Anti-inflammatory activity of a Thai traditional remedy Lom-Pa-Kang and its potential use for knee osteoarthritis therapy

Abstract

Lom-Pa-Kang (LPK) is a Thai traditional remedy consisting of four plants: Piper nigrum L., Zingiber officinale Roscoe, Citrus hystrix DC., and Cynodon aethiopicus, used to treat headaches from migraines and joint pain. The objectives of this study were to investigate anti-inflammatory activity via nitric oxide (NO) production using Griess reagent assay and MTT assay. In addition, the preliminary clinical trial was investigated in osteoarthritis (OA) of knee patients using the Western Ontario and MacMaster University Scales (WOMAC) and Numeric Rating Scales (NRS). The result showed that the ethanolic extract of the dried LPK remedy exhibited higher anti-inflammatory effect on NO production in the murine macrophage cell lines than that of a standard drug (Ibuprofen) with IC50 values of 13.817 ± 0.999 and 56.595 ± 0.116 μg/ml, respectively. Interestingly, all extracts of LPK exhibited non-cytotoxicity upon assessment of cell metabolic activity. The bioactive compounds with anti-inflammatory effect were analyzed using Gas Chromatography Mass-Spectroscopy (GC-MS). Moreover, a four-week preliminary clinical trial in 30 patients of knee OA, aged between 40 and 55 years, had found a statistically significant decrease in NRS pain scores and improvements in WOMAC index scores including pain, stiffness, and physical function, since day seven when compared with baseline (**p < 0.001). No adverse effects were identified in any patients. In conclusion, LPK remedy has significant antiinflammatory activity and offers a potential anti-inflammatory therapeutic approach via localized drug delivery in knee OA patients.