Anti-inflammatory Activity of Kheaw-Hom Remedy in Lipopolysaccharide-stimulated Macrophage Cells and Carrageenan-induced Paw Edema in Rats

Abstract

Introduction: Kheaw-Hom (KH) remedy has been widely used to treat inflammation and fever in children with measles and chickenpox. However, its anti-inflammatory activity, both in vitro and in vivo, has not been scientifically tested.

Objectives: To evaluate the in vitro and in vivo anti-inflammatory activities of KH remedy.

Methods: The in vitro anti-inflammatory activities of the aqueous extract (KHA) and ethanolic extract (KHE) were investigated using lipopolysaccharide (LPS)-stimulated nitric oxide (NO), prostaglandin E₂ (PGE₂ ), and tumor necrosis factor-alpha (TNF-α) in macrophage RAW 264.7 cells. The in vivo anti-inflammatory activity of KHE and KH powder (KHP) was determined using carrageenan-induced paw edema in rats and the PGE₂ production in tissue samples was examined using ELISA kit.

Results: KHE exhibited anti-inflammatory activities through the suppression of PGE₂ , NO, and TNF-α production with IC₅₀ values of 19.69 ± 2.09, 39.93 ± 3.28, and 85.07 ± 2.61 μg/ mL, respectively, while KHA did not. Interestingly, KHP orally administered at the dose of 100 mg/kg significantly reduced rat paw edema at 1, 2, and 3 hours (37.25%, 25.00%, and 27.09%, respectively) while KHE at the dose of 100 mg/kg noticeably reduced at 2 and 3 hours (21.67% and 19.49%) after carrageenan injection. KHP at the dose of 100 mg/kg showed maximum inhibition of PGE₂ production with the PGE₂ levels of 15.46 ± 1.33 ng/mL.

Conclusions: The findings from in vivo study strongly parallel the results of the in vitro study and support the traditional use of KH as a potent anti-inflammatory and antipyretic remedy.