The Chloroform Fraction of Solanum nigrum Suppresses Nitric Oxide and Tumor Necrosis Factor-® in LPS-Stimulated Mouse Peritoneal Macrophages Through Inhibition of p38, JNK and ERK1/2

摘要

Solanum nigrum L., commonly known as black nightshade, is used worldwide fornthe treatment of skin and mucosal ulcers, liver cirrhosis and edema. We aimed to determinenthe anti-inflammatory active fraction of S. nigrum by serial extractions. S. nigrum was firstnextracted with methanol, then fractionated with chloroform and water. The effects of S.nnigrum fractions, diosgenin and u0001-solanine on LPS/interferon-gamma-induced nitric oxiden(NO) and inducible NO synthase (iNOS), or LPS-induced tumor necrosis factor-u0001 (TNF-u0001)nand interleukin (IL)-6, in mouse peritoneal macrophages were determined. Western blottingnanalysis was used to detect LPS-induced phosphorylation of p38, JNK and ERK1/2. Thenchloroform fraction of S. nigrum was cytotoxic in a time and concentration dependentnmanner; however, the methanol and water fractions were not. The chloroform fractionnreduced NO through inhibition of iNOS synthesis and inhibited TNF-u0001 and IL-6 at the levelnof protein secretion; the methanol and water fractions showed a weak or no effect. Thenchloroform fraction also suppressed p38, JNK and ERK1/2. Diosgenin and u0001-solanine werencytotoxic at a high concentration. In particular, diosgenin was able to inhibit TNF-u0001 andnIL-6, but both compounds did not affect LPS-induced iNOS expression. These resultsnindicate that the anti-inflammatory compounds of S. nigrum exist preferentially in thennonpolar fraction, ruling out the possibility that diosgenin and u0001-solanine are the likelyncandidates. The inhibition of iNOS, TNF-u0001 and IL-6 by the chloroform fraction may benCorrespondence to: Dr. Ho-Young Choi, Department of Herbology, College of Oriental Medicine, Kyung HeenUniversity, 1 Hoegi-dong, Dongdaemun-gu, Seoul 130-701, South Korea. Tel: (t82) 2-961-0323, Fax: (t82)n2-965-9372, E-mail: hychoi@khu.ac.krnThe American Journal of Chinese Medicine, Vol. 39, No. 6, 1261–1273n© 2011 World Scientific Publishing CompanynInstitute for Advanced Research in Asian Science and MedicinenDOI: 10.1142/S0192415X11009548n1261npartly due to the suppression of p38, JNK and ERK1/2. Further study is required to identifynthe active compounds of S. nigrum.