关键词：抗氧化剂；前列腺癌；茶；光散射
摘 要：We developed an HPLC method to determine the amount of EGCG encapsulated in the nanoparticles. HPLC analysis showed that chitosan nanoparticles can efficiently entrap EGCG. Also, we developed a method to extract EGCG from the plasma with a recovery value of > 95%. Treatment with EGCG and nanoEGCG resulted in significant inhibition of tumor growth in athymic nude mice implanted with 22R 1 cells and secreted PSA levels. It was found by transmission electron microscopy that the nanoparticles had a size of around 200 nm. We also found that the release of EGCG from these nanoparticles is very slow in acidic medium. On the other hand, release of intestinal fluid is much faster, and around 50% of EGCG was released in 24 hrs. We next determined the effect of oral nanoEGCG on the growth of tumors in TRAMP mice at 24 weeks of age when the mice had established tumors. Prostate and tumor sizes in nanoEGCG- supplemented TRAMP mice were substantially less than in the control animals. nanoEGCG-supplemented TRAMP mice exhibited a significant reduction in the development of prostate cancer measured 32 weeks on test. There was also induction of apoptosis and inhibition of markers of proliferation and angiogenesis in nanoEGCG-treated groups.