Recent advances on the ethnomedicinal plants as immunomodulatory agents
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type 2 (CB2) receptor [25]. However, the alkylamides dodeca-2E,4E,8Z,10Ztetraenoic acid isobutylamide and dodeca-2E,4E-dienoic acid isobutylamide bind to the CB2 receptor more strongly than the endogenous cannabinoids. Alkylamides from Echinacea are a new class of CB2-specific cannabinomimetics, which share the anti-inflammatory properties of anandamide and the cannabinoids from Cannabis sativa. Alkylamides and anandamide (Fig. 1) potently inhibited lipopolysaccharide-induced inflammation in human whole blood and exerted modulatory effects on cytokine expression, but these effects were not exclusively related to CB2 binding [26]. Mollugo verticillata L. (family: Molluginaceae), a weed plant common in warm and/or wet regions of the American continent. The ethanolic extract of this plant showed immunostimulatory activity when peritoneal cells were stimulated in vitro with BCG antigen only. Ethanolic extracts directly increased NO release by peritoneal cells, but suppressed the immune response of these cells when treated with BCG antigen and Mycobacterium tuberculosis whole antigen [27]. Larrea divaricata Cav. (family: Zygophyllaceae) is a plant widely used as popular medicine to treat tumors, infections, and inflammatory diseases in America. The study showed, macrophages harvested from extract treated mice showed no signs of apoptosis. These cells showed a significant increase in NO and TNF-Îą release and exhibited the strongest expression of iNOS. Decoction also increased the phagocytosis of zymosan and the binding of LPS-FITC. The expression of CD14, TLR4 and CR3 was lower in macrophages of mice treated than in controls [28]. O O
N H O
N H
OH
N H Alkylamides
Anandamide
Figure 1. Chemical structure of Alkylamides and anandamide.
2.1.6. European plants Methanol extract of a Portuguese plant Carpobrotus edulis (family: Aizoaceae) showed that the extract inhibit a verapamil sensitive efflux pump of mouse T cell lymphoma cell line thereby rendering these multi-drug resistant cells susceptible to anticancer drugs. It also prime THP-1 human