ABSTRACT
Malignant tumors seriously endanger human life and health, and their treatment has always been a research focus of scientists all over the world. Natural flavonoids and their derivatives have a variety of biological activities, especially regarding antitumor growth, with unique biological activities. They can interfere with the growth cycle of tumor cells, change the mitochondrial membrane potential, promote apoptosis, and can reduce the immune escape of tumor cells and prevent tumor metastasis by improving human immunity. In the human body, they regulate the biological signal transduction, leading to the up-regulation of pro-apoptotic protein expression. They inhibit the growth of solid tumors by regulating the growth of vascular epithelial cells and blocking the formation of blood vessels in tumor tissue. Recent studies have shown that these compounds can play an important role in the treatment of various human tumors and are expected to be developed into new antitumor drugs. This review summarizes the recent research results on the antitumor mechanism of flavonoids and their ability to inhibit tumor growth.
ABSTRACT
AIM To prepare chrysin solid lipid nanoparticles and to evaluate their pharmacokinetic behaviors.METHODS The particle size,Zeta potential and in vitro release rate of nanoparticles prepared by emulsification uhrasonication-low temperature solidification method were determined.Twelve SD rats were randomly divided into two groups and were intragastrically given suspensions of crude drug and nanoparticles,respectively.HPLC was used for the content determination of chrysin in plasma,after which blood drug concentration-time curves were drawn,and pharmacokinetic parameters were calculated.RESULTS The obtained nanoparticles demonstrated the particle size of (207.15 ±30.59) nm,PDI of (0.224 ±0.067) and Zeta potential of (-34.8 ±5.9) mV,respectively,whose accumulative release rate reached 84.36％ within 36 h.Their Cmax [(9.04 ± 1.52) μg/mL] and AUC0～t,[(33.67 ± 3.47) μg · h/mL] were much higher than those of the crude drug (P ＜ 0.01).CONCLUSION Solid lipid nanoparticles can promote the oral absorption and bioavailability of chrysin,with significant sustained-release characteristics.
ABSTRACT
To improve the bioavailability of 10-hydroxycamptothecin, 10-hydroxycamptothecin solid dispersion(HCPT-SD) and 10-hydroxycamptothecin-phospholipid complex-solid dispersion(HCPT-PC-SD) were prepared, and their solubility and dissolution rate were evaluated in this study. SD rates were administered intragastrically with HCPT-SD or HCPT-PC-SD respectively, then their blood samples were collected at different time intervals. The concentration of HCPT in blood was detected by HPLC method with camptothecin as internal standard, and then its pharmacokinetic parameters were calculated and obtained. The results showed that the Cmax, AUC0-t and AUC0-∞ of both kinds of solid dispersion of HCPT were significantly increased than those of crude drug. The AUC0-t of HCPT-SD was increased by 176.87%, and AUC0-t of HCPT-PC-SD was increased by 254.31% as compared with crude drug. Therefore, the two kinds of solid dispersion of HCPT could significantly enhance the bioavailability of HCPT in SD rates, and the effect of HCPT-PC-SD was more obvious.