Aim To measure the penetration of capecitabine from the plasma into tissue and to investigate the pharmacokinetics of its metabolizing into fluorouracil （5-FU） in patients with advanced breast cancer. Methods Twenty...Aim To measure the penetration of capecitabine from the plasma into tissue and to investigate the pharmacokinetics of its metabolizing into fluorouracil （5-FU） in patients with advanced breast cancer. Methods Twenty-seven patients with breast cancer received repeated doses of 1 255 mg·m^-2 of capecitabine twice daily for 7 d. Blood, tumor, and adjacent healthy tissue samples were collected. The concentrations of capecitabine and its metabolite 5-FU were determined by HPLC. The concentration-time profiles of capecitabine and 5-FU were fitted by pharmacokinetic model. The tissue distribution factors for capecitabine and 5-FU, and the AUC ratios of 5-FU to capecitabine in plasma, tumor or adjacent healthy tissue, were calculated with pharmacokinetic parameters, respectively. Results The Ka of capecitabine was 1.17 h^-1 in plasma, 0. 46 h^-1 in tumor tissue, and 0. 61 h^-1 in healthy tissue. The AUCs of capecitabine were 2. 557 1 μg·mL^-1 ·h, 1. 629 2 μg·g^-1·h and 2. 085 0 μg·g^-1· h, and T1/2 was 0. 782 3 h, 1. 528 1 h and 1. 289 6 h in plasma, tumor, and healthy tissue, respectively. The AUCs of 5-FU were 0.418 7 μg·mL^-1 h, 1.671 7 μg·g^-1·h and 1.020 8 μg·g^-1·h; the T1/2 was 0. 631 3 h ,1.204 1 h and 1.031 2 h in plasma, tumor, and healthy tissue, respectively. The tissue distribution factors of capecitabine were 0. 637 1 in tumor （AUCcap-Tumor/AUCcap-plasma） and 0. 851 4 in healthy tissue （AUCcap-HT/AUCcap-plasma . The tissue distribution factors of 5-FU were 3. 992 6 in tumor （AUC5-FU-Tumor/AUC5-FU-plasma） and 2. 438 0 in healthy tissue （AUC5-FU-HT/AUC5-FU-plasma）. The AUC ratios of 5-FU to capecitabine were 0. 1637, 1. 0261, and 0. 489 5 in plasma, tumor, and healthy tissue, respectively. Conclusion The simulation curves for the disposition of capecitabine and its metabolite 5-FU in plasma and tissue basically describe the activation process of capecitabine metabolizing to 5-FU and 5-FU elimination. There are similar distributions for capecitabine in plasma, tumor, and healthy tissue. The exposure of 5-FU in tumor was found to be 3. 992 6 times greater than that in plasma and 2. 438 0 times greater than that in healthy tissue. Capecitabine may metabolize preferentially to 5- FU in tumor tissue after oral administration.展开更多
Brucine has anti-inflammatory and analgesic effects and is the main active compound of the seeds of Strychnos nux-vomica L. To study brucine niosomal gels, a reliable and rapid LC-MS/MS method was established to quant...Brucine has anti-inflammatory and analgesic effects and is the main active compound of the seeds of Strychnos nux-vomica L. To study brucine niosomal gels, a reliable and rapid LC-MS/MS method was established to quantify brucine levels in rats. Tissue distribution and pharmacokinetics of brucine were investigated after topical and oral application of brucine niosomal gels to rats. The plasma concentration versus time profiles suggested that systemic exposure of brucine for oral administration of brucine niosomal gels was higher than that for topical administration, and topical administration showed a relatively sustained release. There was a considerable amount of brucine distributed in the knee joint. These results provided a strong basis for the follow-up study of this preparation.展开更多
文摘Aim To measure the penetration of capecitabine from the plasma into tissue and to investigate the pharmacokinetics of its metabolizing into fluorouracil （5-FU） in patients with advanced breast cancer. Methods Twenty-seven patients with breast cancer received repeated doses of 1 255 mg·m^-2 of capecitabine twice daily for 7 d. Blood, tumor, and adjacent healthy tissue samples were collected. The concentrations of capecitabine and its metabolite 5-FU were determined by HPLC. The concentration-time profiles of capecitabine and 5-FU were fitted by pharmacokinetic model. The tissue distribution factors for capecitabine and 5-FU, and the AUC ratios of 5-FU to capecitabine in plasma, tumor or adjacent healthy tissue, were calculated with pharmacokinetic parameters, respectively. Results The Ka of capecitabine was 1.17 h^-1 in plasma, 0. 46 h^-1 in tumor tissue, and 0. 61 h^-1 in healthy tissue. The AUCs of capecitabine were 2. 557 1 μg·mL^-1 ·h, 1. 629 2 μg·g^-1·h and 2. 085 0 μg·g^-1· h, and T1/2 was 0. 782 3 h, 1. 528 1 h and 1. 289 6 h in plasma, tumor, and healthy tissue, respectively. The AUCs of 5-FU were 0.418 7 μg·mL^-1 h, 1.671 7 μg·g^-1·h and 1.020 8 μg·g^-1·h; the T1/2 was 0. 631 3 h ,1.204 1 h and 1.031 2 h in plasma, tumor, and healthy tissue, respectively. The tissue distribution factors of capecitabine were 0. 637 1 in tumor （AUCcap-Tumor/AUCcap-plasma） and 0. 851 4 in healthy tissue （AUCcap-HT/AUCcap-plasma . The tissue distribution factors of 5-FU were 3. 992 6 in tumor （AUC5-FU-Tumor/AUC5-FU-plasma） and 2. 438 0 in healthy tissue （AUC5-FU-HT/AUC5-FU-plasma）. The AUC ratios of 5-FU to capecitabine were 0. 1637, 1. 0261, and 0. 489 5 in plasma, tumor, and healthy tissue, respectively. Conclusion The simulation curves for the disposition of capecitabine and its metabolite 5-FU in plasma and tissue basically describe the activation process of capecitabine metabolizing to 5-FU and 5-FU elimination. There are similar distributions for capecitabine in plasma, tumor, and healthy tissue. The exposure of 5-FU in tumor was found to be 3. 992 6 times greater than that in plasma and 2. 438 0 times greater than that in healthy tissue. Capecitabine may metabolize preferentially to 5- FU in tumor tissue after oral administration.
基金National Science and Technology Major Projects for"Major New Drugs Innovation and Development"(Grant No.2017ZX09301016)
文摘Brucine has anti-inflammatory and analgesic effects and is the main active compound of the seeds of Strychnos nux-vomica L. To study brucine niosomal gels, a reliable and rapid LC-MS/MS method was established to quantify brucine levels in rats. Tissue distribution and pharmacokinetics of brucine were investigated after topical and oral application of brucine niosomal gels to rats. The plasma concentration versus time profiles suggested that systemic exposure of brucine for oral administration of brucine niosomal gels was higher than that for topical administration, and topical administration showed a relatively sustained release. There was a considerable amount of brucine distributed in the knee joint. These results provided a strong basis for the follow-up study of this preparation.
