Effects of Isoflavonoids on Mouse Lymphocyte Proliferation In Vitro

The suppressive activity of isoflavonoids against lymphocyte proliferation in vitro was examined. Isoflabvonoid derivatives tested were isflavones isolated from Pueraia radix and synthesized 7-O-substituted biochanin A derivatives. The certain isoflavones such as biochanin A and 2-carbethoxybiochainin A were found to possess the suppressive activity against concanavaline A (Con A)-induced lymphocyte proliferation from mouse spleen. Against mixed lymphocyte culture reaction, biochanin A, 2-carbethoxybiochainin A, daidzein, formononetin, genistein and 7-O-isopropylbiochaninl A showed the suppressive activity at $10^{-5}$ M. However, all isoflavones tested did not show the suppressive activity against lymphocyte proliferation induced by B-cell mitogen, lipopolysaccharide (LPS). In general, isoflavones were revealed to be less active than flavones/flavonols.