去氫梔子甘在TPA所引起的CD-1品系老鼠皮膚腫瘤、發炎反應、上皮細胞增生、ODC活性、H2O2及MPO活性的增加方面皆在本實驗中被發現具有抑制的作用。 我們在老鼠背部以20nmol/200μl accetone 的B[a]P處理10週及15nmol/200μl accetone的TPA處理20週來引起皮膚的腫瘤實驗中，發現0.2及1.0μmol的去氫梔子甘各對腫瘤有84%及89%的抑制作用；以0.5nmol TPA/20μl accetone 塗抹在老鼠耳朵上以測試發炎反應，結果發現上述兩種濃度的去氫梔子甘各有41及43%的抑制作用；以TPA塗抹於老鼠皮膚尚在取下皮膚作切片觀察，結果發現以去氫梔子甘處理者對TPA所以起的增生作用有抑制效果；再TPA所引起的ODC(一種皮膚癌的指標)活性測試實驗中也發現兩種濃度的去氫梔子甘對ODC活性的抑制作用各為85%及94%；而再以TPA來刺激老鼠皮膚而引起H2O2及MPO的形成實驗中也發現去氫梔子甘有抑制作用。 由上述實驗結果中可知去氫梔子甘對TPA所引起的癌促進作用有抑制作用，所以去氫梔子甘可能具有癌症化學抑制劑的作用。 The effects of topical application of geniposide on 12-O-tetradecaonyl-phorbol-13-acetate(TPA)-induced promotion of skin tumors, hyperplasia, ornithine decarboxylase (ODC)and inflammation were evaluated in female CD-1 mice.Topical application of geniposide (0.2 or 1.0μmol)with TPA(15nmol)twice weekly for 20 weeks to mice previously initiated with benzo[a]pyrene (B[a]P) inhibited the number of TPA-induced tumors per mouse by 84 or 89%, respectively.Preapplication of the same amount of geniposide also afforded significant protection against TPA-induced hyperplasia in the ear skin. Topical application of geniposide inhibited tumor promoter-caused induction of epidermal ODC activity by TPA(5 nmol).The topical application of geniposide inhibited tumor promoter-caused induction of epidermal ODC activity by TPA(5 nmol).The topical application of geniposide (0.2 or 1.0μmol) inhibited TPA-induced edema of mouse ears by 41 or 43%,respectively.Pretreatment of mouse skin with various amounts of geniposide caused inhibition of hydrogen peroxide (H2O2)and myeloperoxidase (MPO)formation by TPA. These results indicate that geniposide possesses potential as a cancer chemopreventive agent against tumor promotion.
