Transplacental Distribution of Lidocaine and Its Metabolite in Peridural Anesthesia Administered to Patients With Gestational Diabetes Mellitus

Simultaneous determination of five alkaloids from Rauvolfia vomitoria in rat plasma by LC-MS/MS: Application to a comparative pharmacokinetic study in normal and type 2 diabetic rats

Rauvolfia vomitoria is widely distributed in the tropical regions of Africa and Asia, and has been used in traditional folk medicine in China. Indole alkaloids were found to be major bioactive components, while the effects of diabetes mellitus on the pharmacokinetic parameters of the components have not been reflected in vivo. In this study, an efficient and sensitive liquid chromatography-tandem mass spectrometry method was developed and validated for the simultaneous determination of five ingredients of R. vomitoria in rats. Detection was implemented in multiple-reaction-monitoring mode with an electrospray positive-ionization source. Validation parameters were all in accordance with the current criterion. The established method was effectively employed to compare the pharmacokinetic behaviors of five alkaloids (reserpine, yohimbine, ajmaline, ajmalicine, and serpentine) between normal and type 2 diabetic rats. The single-dose pharmacokinetic parameters of the five alkaloids were determined in normal and diabetic rats after oral administration of 100 and 200 mg/kg body weight. The results indicated that diabetes mellitus significantly altered the pharmacokinetic characteristics of yohimbine, ajmaline, and ajmalicine after oral administration in rats. This is an attempt to provide some evidence for clinicians that may serve as a guide for the use of antidiabetic medicine in clinical practice.

Physico-chemical properties and gestational diabetes predict transplacental transfer and partitioning of perfluoroalkyl substances

BACKGROUND

Per- and polyfluoroalkyl substances (PFASs) are a growing public health concern. Some longer chain PFASs bioaccumulate and many compounds persist in the environment for long time periods. Recent studies have established their ability to pass through placenta, yet data on the transplacental transfer efficiency and partitioning of short and long chain PFASs in blood matrices are limited.

OBJECTIVES

To assess predictors of the partitioning of 17 PFAS compounds detected in the maternal serum, umbilical cord serum and whole cord blood samples from matched mother-newborn pairs from two Faroe Islands cohorts.

METHODS

We examined 151 mother-newborn pairs from two successive Faroese birth cohorts. Cord:maternal serum (transplacental transfer) and serum:whole cord blood (blood partitioning) ratios were estimated for 17 PFAS compounds. We also examined the relationships of these ratios with maternal, newborns', and physico-chemical properties using multivariable regression analyses.

RESULTS

Moderate to high correlations were observed between maternal and cord serum PFAS concentrations (ρ: 0.41 to 0.95), indicating significant transfer of these compounds from the mother to the fetus. Median transplacental transfer ratios were generally below 1, except for perfluorooctane sulfonamide (FOSA), and ranged between 0.36 for perfluorodecanoate (PFDA) and perfluoroundecanoate (PFUnDA) and 1.21 for FOSA. Most PFASs exhibited a preference to the serum component of the blood, except FOSA and perfluoroheptanoate (PFHpA), with blood partitioning ratios ranging from 0.36 for FOSA to 2.75 for PFUnDA. Both the functional groups and carbon chain length of different PFASs were important predictors of transplacental transfer and blood partitioning. We observed a U-shaped relationship between transplacental transfer ratios and carbon chain length for perfluorocarboxylates and perfluorosulfonates. Importantly, gestational diabetes was also a strong predictor of transplacental transfer ratios, with significantly higher transfer in mothers with gestational diabetes.

CONCLUSIONS

Our findings provide a better understanding of the transplacental transfer and blood partitioning of a large number of PFAS compounds. Results elucidate the importance of chemical structure for future risk assessments and choice of appropriate blood matrices for measurement of PFAS compounds.

Effect of type 2 diabetes mellitus on the pharmacokinetics and transplacental transfer of nifedipine in hypertensive pregnant women

AIMS

Diabetes mellitus can inhibit cytochrome P450 3A4, an enzyme responsible for the metabolism of nifedipine, used for the treatment of hypertension in pregnant women. We aimed to assess the effect of type 2 diabetes mellitus (T2DM) on the pharmacokinetics, placental transfer and distribution of nifedipine in amniotic fluid in hypertensive pregnant women.

METHODS

The study was conducted in 12 hypertensive pregnant women [control group (CG)] and 10 hypertensive pregnant women with T2DM taking slow-release nifedipine (20 mg, 12/12 h). On the 34th week of gestation, serial blood samples were collected (0-12 h) after administration of the medication. At delivery, samples of maternal and fetal blood and amniotic fluid were collected for determination of nifedipine distribution in these compartments.

RESULTS

The median pharmacokinetic parameters of CG were: peak plasma concentration (C_max ) 26.41 ng ml^-1 , time to reach C_max (t_max ) 1.79 h, area under the plasma concentration vs. time curve from 0-12 h (AUC_0-12 ) 235.99 ng.h ml^-1 , half-life (t½) 4.34 h, volume of distribution divided by bioavailability (Vd/F) 560.96 l, and Cl_T /F 84.77 l h^-1 . The parameters for T2DM group were: C_max 23.52 ng ml^-1 , t_max 1.48 h, AUC_0-12 202.23 ng.h ml^-1 , t½ 5.00 h, Vd/F 609.40 l, and apparent total clearance (Cl_T /F) 98.94 l h^-1 . The ratios of plasma concentrations of nifedipine in the umbilical vein, intervillous space and amniotic fluid to those in the maternal vein for CG and T2DM were 0.53 and 0.44, 0.78 and 0.87, respectively, with an amniotic fluid/maternal plasma ratio of 0.05 for both groups. The ratios of plasma concentrations in the umbilical artery to those in the umbilical vein were 0.82 for CG and 0.88 for T2DM.

CONCLUSIONS

There was no influence of T2DM on the pharmacokinetics or placental transfer of nifedipine in hypertensive women with controlled diabetes.