Stereoselective and Simultaneous Analysis of Ginsenosides from Ginseng Berry Extract in Rat Plasma by UPLC-MS/MS: Application to a Pharmacokinetic Study of Ginseng Berry Extract.

The role of ginseng berry extract (GBE) has been attributed to its anti-hyperglycemic effect in humans. However, the pharmacokinetic characteristics of GBE constitutes after oral GBE administration have not been established yet. In this study, stereoselective and simultaneous analytical methods for 10 ginsenosides (ginsenoside Rb1, Rb2, Rc, Rd, Re, Rg1, S-Rg2, R-Rg2, S-Rg3, and R-Rg3) were developed using ultra-performance liquid chromatography, coupled with electrospray ionization triple quadrupole tandem mass spectrometry (UPLC-MS/MS), for the pharmacokinetic study of GBE. Furthermore, the pharmacokinetic profiles of 10 ginsenosides after oral GBE were evaluated in rats. All analytes were detected with a linear concentration range of 0.01⁻10 µg/mL. Lower limits of detection (LLOD) and quantification (LLOQ) were 0.003 and 0.01 µg/mL, respectively, for all 10 ginsenosides. This established method was adequately validated in linearity, sensitivity, intra- and inter-day precision, accuracy, recovery, matrix effect, and stability. Relative standard deviations for all intra- and inter-precision of the 10 ginsenosides were below 11.5% and accuracies were 85.3⁻111%, which were sufficient to evaluate the pharmacokinetic study of oral GBE in rats. We propose that Rb1, Rb2, Rc, Rd, Re, Rg1, S-Rg2, R-Rg2 and/or S-Rg3 were appropriate pharmacokinetic markers of systemic exposure following oral GBE administration.

A New Therapeutic Approach Using a Calcilytic (AXT914) for Postsurgical Hypoparathyroidism in Female Rats.

Postsurgical hypoparathyroidism is the most common complication of thyroid surgery. Conventional therapy with high-dose calcium and vitamin D can correct hypocalcemia but can increase the risk of hypercalciuria, renal stones, or ectopic calcification. The aim of the present study was to investigate the efficacy of a calcium-sensing receptor antagonist, also called a calcilytic (AXT914), in rat models of postsurgical hypoparathyroidism. Two postsurgical hypoparathyroidism rat models were made by hemi-parathyroidectomy or total parathyroidectomy with autotransplantation in 10-week-old female Wistar rats. AXT914 or vehicle was administered orally for 2 to 3 weeks. Serum PTH, calcium, and phosphorus levels, and the urinary excretion of calcium were measured. Autotransplanted parathyroid tissues were collected and examined histologically. In the hemi-parathyroidectomy model, the oral administration of the calcilytic AXT914 (5 and 10 mg/kg) for 2 weeks increased serum PTH and calcium levels and decreased serum phosphorus levels and urinary calcium excretion. In the total parathyroidectomy with autotransplantation model, the oral administration of AXT914 (10 mg/kg) for 3 weeks increased serum PTH and calcium levels and decreased serum phosphorus levels. The serum PTH and calcium levels increased by AXT914 were maintained for 1 week, even after discontinuation of the drug. In conclusion, AXT914 increased PTH secretion in rat models of postsurgical hypoparathyroidism, thereby correcting abnormal calcium and phosphorus homeostasis. Furthermore, AXT914 improved the functional recovery of autotransplanted parathyroid tissues.