| Objective: Considering the importance of inflammation in the pathogenesis of osteoarthritis (OA) and
induction of pain, this study was aimed to investigate the effect of L-carnitine supplementation on serum
inflammatory mediators and OA-associated pain in females with knee OA.
Methods: In this clinical trial, 72 females with mild to moderate knee osteoarthritis started the study, divided
into 2 groups to receive 750 mg/day L-carnitine (n D 36) or placebo (n D 36) for 8 weeks. Serum levels of
Interleukine-1b (IL-1b), high-sensitivity C-reactive protein (hs-CRP), matrix metalloproteinases (MMPs)-1 and
-13, and visual analog scale (VAS) for pain were assessed before and after supplementation. Data were analyzed
by t test, Wilcoxon signed rank test, Mann-Whitney U test, and analysis of covariance.
Results: Only 69 patients (33 in the L-carnitine group and 36 in the placebo group) completed the study. LCarnitine
supplementation decreased serum IL-1b and MMP-1 levels significantly (p D 0.001 and p D 0.021,
respectively); however, serum hs-CRP and MMP-13 levels did not change significantly (p > 0.05). In the
placebo group, serum IL-1b levels increased significantly (p D 0.011), whereas other studied biomarkers did not
change significantly. The mean VAS score decreased significantly in the L-carnitine and placebo groups by
52.67% and 21.82%, respectively (p < 0.001). Significant differences were only observed between the 2 groups
in serum IL-1b (p < 0.001) and MMP-1 (p D 0.006) levels and mean VAS score (p D 0.002) after adjusting for
baseline values and covariates.
Conclusion: Despite observed beneficial effects of short-term supplementation of L-carnitine in decreasing
serum inflammatory mediators and improving pain in knee OA patients, further studies are needed to achieve
concise conclusions. |