A molecular pharmacology study into the anti-inflammatory actions of Euphorbia hirta L. on the LPS-induced RAW 264.7 cells through selective iNOS protein inhibition

• Published in: Journal of natural medicines Vol. 64; no. 3; pp. 330 - 335
• Main Authors: Shih, Mei-Fen, Cheng, Yih-Dih, Shen, Chia-Rui, Cherng, Jong-Yuh
• Format: Journal Article
• Language: English
• Published: Japan Springer Japan 01.07.2010
• Subjects: Animals; Anti-Inflammatory Agents - chemistry; Anti-Inflammatory Agents - pharmacology; Biomedical and Life Sciences; Biomedicine; Blotting, Western; Cell Line; Complementary & Alternative Medicine; Dinoprostone - metabolism; Enzyme-Linked Immunosorbent Assay; Euphorbia - chemistry; Interleukin-6 - metabolism; Lipopolysaccharides - toxicity; Macrophages - drug effects; Macrophages - metabolism; Medicinal Chemistry; Mice; Molecular Structure; Nitric Oxide - metabolism; Nitric Oxide Synthase Type II - genetics; Nitric Oxide Synthase Type II - metabolism; Original Paper; Pharmacology/Toxicology; Pharmacy; Plant Extracts - chemistry; Plant Extracts - pharmacology; Plant Sciences; Reverse Transcriptase Polymerase Chain Reaction; Tumor Necrosis Factor-alpha - metabolism; iNOS; Inflammation; NO specific inhibitor; L; β-Amyrin
• ISSN: 1340-3443; 1861-0293
• DOI: 10.1007/s11418-010-0417-6

Euphorbia hirta L. has been widely used in India and Chinese society. The molecular pharmacology basis of its anti-inflammatory effect is revealed in this work. The ethanol extract of Euphorbia hirta L. (Eh) and its active component were studied in lipopolysaccharide (LPS)-activated macrophage cells (RAW 264.7) as an established inflammation model. After activation, nitric oxide (NO) production and expression of iNOS protein and iNOS mRNA were measured by using a colorimetric assay (Griess reagent), western blotting, and reverse transcription polymerase chain reaction (RT-PCR), respectively. The alteration in the content of PGE 2 , TNFα, and IL-6 was concurrently monitored by ELISA. In results, we found that in the concentration range without showing cytotoxicity, Eh produced a remarkable anti-inflammatory effect via its active component of β-amyrin and showed a dose-related inhibition of LPS-induced NO production. This phenomenon is in accordance with a substantial inhibition of iNOS protein. However, the expression of iNOS gene was unaffected by Eh treatments. Compared with indomethacin, Eh has much more potency and a specific action of NO inhibition but Eh works less specifically on PGE 2 , IL-6, and TNF-α inhibition. The extract of Euphorbia hirta L. and its component β-amyrin are able to block most of the iNOS protein functions and NO induction, and could therefore be new selective NO inhibitors with great potential in treating arthritis inflammation.