Randomized double-blind placebo-controlled study of the efficacy of Litsea japonica fruit extract in subjects with mild to moderate knee osteoarthritis

In this randomized, double-blind, placebo-controlled study, we evaluated the efficacy of Litsea japonica fruit extract (LJF) in subjects with knee osteoarthritis (OA). Eighty-seven 50- to 70-year-old subjects with knee OA were assigned to a placebo group, a low-dose LJF group (LJF-L, 100 mg/d) or a high-dose LJF group (LJF-H, 200 mg/d) for 12 weeks. The outcome measures were pain score assessed using a visual analog scale (VAS); Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores; and blood and urine biomarkers. In response to LJF consumption, VAS scores; WOMAC total scores; WOMAC scores on the pain, stiffness and function subscales; and blood MMP-9 levels significantly improved over the course of the examined 12-week period (P = 0.0001, 0.0102, 0.0293, 0.002, 0.0152 and 0.026, respectively). This study suggests that LJF may reduce joint pain and stiffness and improve joint function in subjects with painful knee OA. (C) 2017 Elsevier Ltd. All rights reserved.