Effect of Tea Extracts and Phenolic Components on Immunoglobulin Production by Mesenteric Lymph Node Lymphocytes of Sprague-Dawley Rats.

Abstract

We examined the effect of tea extracts on immunoglobulin (Ig) production of mesenteric lymph node lymphocytes of Sprague-Dawley rats and found that various extracts suppressed the production of lgA, IgG, and lgM. In addition, the original extracts of green and black teas strongly enhanced lgE production, and their 10' or 103 times diluted samples exerted an inhibitory effect. Similarly, tea polyphenols having a triphenol group enhanced lgE production at I mM and inhibited it at concentrations below 100 pM. On the contrary, diphenolic epicatechin did not affect lgE production. Though all tea polyphenols exerted inhibitory effect on the production of lgA and lgG at concentrations above 10 pM, triphenolic compounds, such as epigallocatechin gallate, gallic acid and pyrogallol, exerted an enhancing tendency on lgA production at 0.1 pM. These results suggest that the lg production-regulating activity of tea extract is partly due to tea polyphenols, especially those having a triphenol group.

Enhancement of phagocytic activity of macrophage-like cells by pyrogallol-type green tea polyphenols through caspase signaling pathways

“…These results suggest that the pyrogallol-type structure, such as the pyrogalloltype B-ring or galloyl group, is an important factor in the phagocytic activity of VD3-differentiated HL60 cells. This is similar to the results of Yamada et al (1997), who showed that pyrogallol-type polyphenols, such as EGCG, gallic acid and pyrogallol, enhanced Polyphenols with a pyrogallol-type structure induce the apoptosis of malignant cells through a caspase signaling pathway (Saeki et al 2000;Hayakawa et al 2001;Vergote et al 2002); however, caspase is a protease playing an important role not only in apoptosis but also in innate immunity (Martinon and Tschopp 2004;Winoto 2004), and regulates phagocytic activity in macrophages, such as dendritic cells (Ho et al 2009); therefore, we investigated the involvement of the caspase pathway in phagocytic activity. As shown in Fig.…”

The anti-allergic effect of the ethyl acetate fraction from anEcklonia kuromeextract

“…In this study, epigallocatechin gallate (EGCG; Sigma-Aldrich Co., St. Louis MO, USA), a tea catechin, was used as a typical natural inhibitor, since EGCG is well known to possess anti-allergic effect via various inhibition mechanisms (Tachibana, 2011;Yamada, Watanabe, Kaku, Hassan, & Sugano, 1997;Yoshino, Kawaguchi, Yamazaki, & Sano, 2010).…”

Recent topics in anti‐oxidative factors

“…Though EC and ECg have diphenolic B ring and EGC and EGCg have triphenolic B ring, it has been reported that triphenolic compounds enhance IgA production of rat lymphocytes, but diphenolic compounds does not [4]. These compounds have been reported to exert diverse biological effects, such as anti-viral, anti-mutagenic, anti-cancer, and anti-allergic activities.…”