Suppressive effects of wild bitter gourd (Momordica charantia Linn. var. abbreviata ser.) fruit extracts on inflammatory responses in RAW 264.7 macrophages

Aim of the studyBitter gourd (Momordica charantia) is used to treat various diseases including inflammation. A wild species of bitter gourd, Momordica charantia Linn. var. abbreviata ser. (WBG), is considered to be more potent in disease prevention than is bitter gourd; however, little is known about the biological and physiological characteristics of WBG.Materials and methodsThe present study investigated the anti-inflammatory effect of WBG on lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages.ResultsAmong the hot water, 95% ethanol, and ethyl acetate extracts of WBG, the ethanol extract showed the greatest reduction of LPS-induced nitric oxide (NO) and prostaglandin E2 (PGE2) production and inducible nitric oxide synthase (iNOS) and pro-interleukin-1β expression. LPS-induced cyclooxygenase-2 expression was not affected by WBG extracts. Compared with WBG, extracts from bitter gourd showed a lesser inhibition of LPS-induced events. Electrophoretic mobility shift assay further showed that both the hot water and the ethanol extracts of WBG inhibited NF-κB activation. Although information is lacking on the bioactive components of WBG, the phenolic compound contents of each extract significantly paralleled its anti-inflammatory ability (r = 0.74, 0.88 and 0.65 for NO, PGE2 and iNOS expression, respectively, P < 0.05).ConclusionsThese results suggest that WBG is beneficial for reducing LPS-induced inflammatory responses by modulating NF-κB activation.