The Pharmacokinetic Study Of HPD Injection

Hydroxylation panoxadiol(HPD) is a new triterpenenoid which is isolated and identified from saponins in the stems and leaves of American ginseng for the first time. Previous investigation shows that HPD prepared by chiral structure modification reaches the industrialization level, possesses significant anti-cervical cancer activity as well as low toxicity and is a potential state categoryⅠnew drug. Pharmacokinetics is one of the most important in developing original new drug, nevertheless at present pharmacokinetics of HPD injection in rat has not been well studied.In this thesis the quantitative analysis ultra-performance liquid chromatography coupled with tandem mass spectrometry(UPLC-MS/MS) was first established for the detection of HPD in plasma, tissues and excretion in rat after intravenous administration of HPD injection to assess absorption, distribution and excretion of HPD as well as the plasma protein binding of HPD in vitro. Besides for the first time qualitative analysis assay based on ultra-performance liquid chromatography coupled with Q-TOF spectrometry(UPLC-Q-TOF/MS) was developed for the detection of the in vivo metabolites in rat to study and reveal the metabolic regularity of HPD in rat. The obtained results are as followed: 1. Plasma concentration-time profile study of HPD injectionThe quantitative analysis UPLC-MS/MS was first established for the detection of HPD in plasma, and plasma concentration of HPD was detected after three different intravenous doses of HPD injection(8.0, 16.0, 32.0mg/kg HPD) was determined. Data was calculated by DAS3.0 software, and the results were as follows: in the low-dose group, T1/2 5.76±1.46 h, Cmax 5535.33±610.76 μg/L, Tmax 0.10±0.00 h, AUC(0-t) 11670.15±1364.30 μg·h/L, AUC(0-∞) 12023.88 ±1573.57 μg·h/L, Vz 5.52±1.22 L/kg, CLz 0.67±0.08 L/h/kg; in the middle-dose group, T1/2 6.50±1.05 h, Cmax 12344.29±1631.71, Tmax 0.10±0.00 h, AUC(0-t) 26253.13±4307.29μg·h/L, AUC(0-∞) 26986.39±4635.18μg·h/L, Vz 5.63±0.90 L/kg, CLz 0.61±0.10 L/h/kg; in the high-dose group, T1/2 6.41±1.40 h, Cmax 24683.57±3693.03, Tmax 0.10±0.00 h, AUC(0-t) 48503.57±5309.65μg·h/L, AUC(0-∞) 49165.27±5335.80μg·h/L, Vz 6.07±1.41 L/kg, CLz 0.66±0.07 L/h/kg. It is shown that AUC and Cmax were associated with HPD in a dose-dependent manner,which displayed the first order kinetic process. Vz 5.52-6.07 L/kg, indicating that HPD was not only distributed in blood but also in tissues. T1/2 5.76-6.50 h and CLz 0.61-0.67L/h/kg, indicating that the elimination of HPD injection was slow. 2. Distribution study of HPD injectionQualitative analysis assay based on UPLC-MS/MS was first established for the detection of HPD in rat tissues. The concentration of HPD at 15 min, 1h, 4h and 6h were assessed in heart, lung, spleen, liver, kidney, small intestine, large intestine, stomach, muscle, fat, brain, uterus and testicle after the intravenous administration of 16.0mg/kg HPD injection. The results showed that HPD injection extensively and rapidly distributed to the examined tissues, and high levels were observed in kidney and uterus. In addition, the distribution of HPD in other tissues showed differences in a time-dependent manner, and also demonstrated no long-term accumulation in all the tissues. 3. Plasma protein binding rate of HPD injection in vitroUPLC-MS/MS methods were first established for the determination of HPD concentration in rat plasma, dog plasma, human plasma and dialysate. Equilibrium dialysis method was used to determine the plasma protein binding rates(PPB) of HPD with three different plasma(rat plasma, dog plasma and human plasma). The results were as follows: PPB of different HPD concentrations including 0.1μg/m L、4.0μg/m L and 16.0μg/m L in rat plasma were 68.36%, 69.07%, 70.48%, in dog plasma they were 67.66%, 74.42%, 72.32%, and in human plasma they were 65.19%, 68.40%, 66.09%, respectively. The result suggested that PPB of HPD injection whose concentration ranging from 0.1μg/m L to 16.0μg/m L was not in a dose-dependent manner and showed no significant generic difference. 4. Excretion study of HPD injectionA quantitative analysis method based on UPLC-MS/MS was first developed for the detection of HPD in rat bile, urine and feces. The concentration of HPD in bile, urine and feces at different time points were evaluated after the intravenous injection of 16.0mg/kg HPD. The results demonstrated that the cumulative excretion percentage of HPD in bile in 36 hours was just 0.06%, while in urine and feces in 72 hours the data were 46.39% and 0.18%, respectively. The results suggested that feces was the primary excrete route of HPD injection in rat, rather than bile and urine, and that the cumulative excretion percentage of HPD in these three samples was approximately 46.63%, indicating that the bioconversion of HPD in rat was mainly metabolic elimination. 5. Metabolism study of HPD injectionThe qualitative analysis based on UPLC-Q-TOF/MS was first developed for the detection of the metabolites in rat bile, urine and feces. The metabolites of HPD over a 72 h period in feces, urine and bile were initially detected after intravenous injection of 16.0mg/kg HPD. The results demonstrated that thirteen metabolites including twelve phaseⅠmetabolites were identified in feces and urine among a total of twenty-one detected metabolites excluding prototype drug, and that five phaseⅡmetabolites were detected in bile among a total of eight identified metabolites. The results suggested that phaseⅠmetabolism and phaseⅡmetabolism simultaneously occured, and that phaseⅠmetabolism was mainly in feces and urine, however phaseⅡmetabolism was in bile.