Effect of X-ray irradiation on pharmacokinetics of irinotecan hydrochloride and expression of CES1 and CYP3A1 in rats.

Concurrent chemoradiation with irinotecan hydrochloride (CPT-11) is accepted for cancer treatment. However, the effects of X-ray irradiation on chemotherapeutics in the plasma remain unclear. We evaluated the pharmacokinetics of CPT-11 in rats after exposure to X-ray irradiation and examined the changes of protein and mRNA expression of CES1 and CYP3A1. The X-ray irradiation with 1 Gy and 5 Gy was delivered to the whole body of rats. CPT-11 at 30 and 60 mg/kg, respectively, was intravenously infused 24 h after irradiation. CPT-11 was determined by RP-HPLC in plasma. ELISA and PCR were used to analyze the protein and mRNA expression of CES1 and CYP3A1, respectively. Compared with control rats, the X-ray irradiation decreased the AUC of CPT-11 (30 mg/kg) by 15.6% at 1 Gy and 39.0% at 5 Gy and increased the CL by 60.0% at 5 Gy. The X-ray irradiation could also decrease the AUC of CPT-11 (60 mg/kg) and increase the CL. In addition, the protein and mRNA expression of CES1 and CYP3A1 were increased significantly in rats after irradiation. This study found significant changes in the pharmacokinetics of CPT-11 in rats after exposure to X-ray irradiation, and they might be due to significant increases in the expressions of CYP3A1 and CES1. The pharmacokinetics of CPT-11 should be rechecked, and the optimal CPT-11 dose should be reevaluated during concurrent chemoradiation therapy.

Research Progress and Application of Penetration Enhancers in TCM Transdermal Medicine Delivery Preparations / 中国中医药信息杂志

Because TCM transdermal medicine delivery preparations are hot spots in domestic researches, the rational application of penetration enhancers in prescriptions and the evaluation methods become increasingly important. This article reviewed the recent application of natural penetration enhancers and synthetic penetration enhancers in the prescription design of TCM transdermal medicine delivery preparations, and analyzed the existing problems and development prospects.