In Vitro Stability and Pharmacokinetic Study of Pedunculoside and Its Beta-CD Polymer Inclusion Complex.

Pedunculoside, a triterpene saponin derived from various Ilex species, holds potential as a treatment for cardiovascular diseases. However, its clinical application is hindered by poor bioavailability, rapid elimination, and extensive intestinal metabolism to rotundic acid. To address these issues, a water-soluble inclusion complex of pedunculoside, namely, the beta-CD polymer inclusion complex of pedunculoside (pedunculoside-ßCDP), was prepared in this study, and a comparative in vitro stability and pharmacokinetic behavior study was performed between pedunculoside and pedunculoside-ßCDP. Both pedunculoside and pedunculoside-ßCDP exhibited the highest stability in simulated gastric fluid and simulated intestinal fluid but were readily metabolized when co-incubated with Bifidobacterium adolescentis and Bifidobacterium breve. An LC-MS/MS analytical method for the simultaneous determination of pedunculoside and rotundic acid in rat plasma was successfully established, validated, and applied to investigate the pharmacokinetic behavior after rats were intravenously administered with pedunculoside or pedunculoside-ßCDP. The results indicated that pedunculoside-ßCDP could significantly improve the pharmacokinetic profile of pedunculoside by increasing plasma exposure, retarding elimination, and reducing intestinal metabolism. This study enhances our understanding of pedunculoside-ßCDP's metabolic fate and pharmacokinetic properties and potentially advances its further research, development, and clinical application.

Development and validation of a dried blood spots assay for metabolic profiling of ginsenosides using ultra-high performance liquid chromatography-mass spectrometry.

ETHNOPHARMACOLOGICAL RELEVANCE: Panax ginseng C.A. Meyer., a famous and valuable traditional Chinese medicine with thousand years of history for its healthcare and therapeutic effects. It is necessary and meaningful to study the pharmacokinetic behavior of ginsenosides in vivo as they are the most active components. Dried blood spots (DBS) are a mature and advanced blood collection method with meet the needs for the measurement of numerous analytes. AIM OF THE STUDY: This study aimed to explore the feasibility on DBS in the metabolic profile analysis of complex herbal products. MATERIALS AND METHODS: An ultra-high performance liquid chromatography-mass spectrometry (UHPLC-MS/MS) method was developed and validated for the determination of ginsenosides. The preparation of DBS samples was conducted by spiking the whole blood with analytes to obtain 20 µL of blood spots on Whatman 903 collection card. A punched dish of 10 mm in diameter was extracted with 70 % methanol aqueous solution, digoxin was used as an internal standard. Target compounds were separated on a Waters T3 column (2.1 × 100 mm, 1.8 µm) with acetonitrile and water (0.1 % formic acid) at a flow rate of 0.4 mL/min. RESULTS: The various ginsenosides showed good linearity in the range of 1-2000 ng/mL. The extraction recoveries and matrix effects of the target analytes were above 82.2%. The intra- and inter-batch accuracy and precision were within the limits of ≤15% for all tested concentrations. Moreover, the collected dried blood spot samples could be stably stored at room temperature for 14 days and 4 °C for 1 month without being affected. And it is delightful that the DBS-based analysis is compatible or even superior to the conventional protein precipitation in terms of sensitivity, linearity, and stability. In particular, the target analytes are stable in the DBS sampling under normal storing condition and the sensitivity for some trace metabolites of ginsenosides, such as 20(S)-Rg3, 20(R)-Rg3, F1, Rk1, Rg5, etc. increases 3-4 folds as evaluated by LLOQ. CONCLUSIONS: The established method was successfully applied to pharmacokinetic studies of ginseng extract in mice, this suggests a more feasible strategy for pharmacokinetic study of traditional and natural medicines both in animal tests and clinical trials.

Novel microporous resin-based polymer device for sustained glipizide release: Production, characterization and pharmacokinetic study.

The objective of this study was to explore an innovative sustained release technology and design a new microporous resin-based polymer device (RPD) for controlled release of glipizide (GZ). Photocurable resin was applied to prepare the resin layer to control GZ release. The impact of formulation parameters consisting of the type and amount of pore formers and pH modifiers, photocurable curing time as well as the weight of resin layer on GZ release were examined. The GZ-RPD was fabricated applying 24 mg of resin layer with PEG400 (100 % of the resin weight) as pore former and 10 mg of Na2CO3 as pH modifier. Scanning electron microscopy (SEM) demonstrated resin particles presenting a porous structure constituted the resin layer. The GZ-RPD possessed prolonged Tmax and reduced Cmax relative to commercial tablets. The relative bioavailability of the RPDs as well as commercial tablets was 93.65 % since the AUC0-24 h were 6111.05 ± 238.89 ng·h/mL and 6525.09 ± 760.59 ng h/mL, respectively. The release mechanism of the GZ-RPD was discussed. This paper provided an innovative concept to produce controlled GZ release oral formulation fabricated by photocurable resin, which demonstrated both excellent in vitro release and in vivo pharmacokinetics.

Physiologically based pharmacokinetic (PBPK) modeling of BDE-209 following oral exposure in Chinese population.

The wide usage of decabromodiphenyl ether (BDE-209) as additive brominated flame retardant has caused its widespread occurrence in the environment and high exposure risk in humans. Estimating its internal exposure dose and reconstruction of external exposure dose using physiologically based pharmacokinetic (PBPK) modelling approach is a key step in the risk assessment of BDE-209. However, the PBPK model for BDE-209 is currently unavailable. This study has established two oral permeability-limited PBPK models of BDE-209 without enterohepatic recirculation (EHR) (model 1) and with EHR (model 2) for Chinese population. Using the in vitro experiments, the average binding of BDE-209 to human plasma protein (99.64% ± 2.97%) was obtained. Moreover, blood sample analysis and systematic literature review were performed to obtain internal and external exposure data of BDE-209 used for model calibration and validation. The predictions of both models were within 2-fold of the observed, and a longer half-life of serum BDE-209 was observed in model 2 than model 1. Based on the models, a human biomonitoring guidance value (HBM-GV) of 93.61 µg/g lw was derived for BDE-209, and there is no health risk found for Chinese population currently. This study provides new quantitative assessment tools for health risk assessment of BDE-209.

Magnetothermal regulation of in vivo protein corona formation on magnetic nanoparticles for improved cancer nanotherapy.

Engineering the protein corona (PC) on nanodrugs is emerging as an effective approach to improve their pharmacokinetics and therapeutic efficacy, but conventional in vitro pre-programmed methods have shown great limitation for regulation of the PC in the complex and dynamic in vivo physiological environment. Here, we demonstrate an magnetothermal regulation approach that allows us to in situ modulate the in vivo PC composition on iron oxide nanoparticles for improved cancer nanotherapy. Experimental results revealed that the relative levels of major opsonins and dysopsonins in the PC can be tuned quantitatively by means of heat induction mediated by the nanoparticles under an alternating magnetic field. When the PC was magnetically optimized in vivo, the nanoparticles exhibited prolonged circulation and enhanced tumor delivery efficiency in mice, 2.53-fold and 2.02-fold higher respectively than the control. This led to a superior thermotherapeutic efficacy of systemically delivered nanoparticles. In vivo magnetothermal regulation of the PC on nanodrugs will find wide applications in biomedicine.

Application of solid lipid nanoparticles as a long-term drug delivery platform for intramuscular and subcutaneous administration: In vitro and in vivo evaluation.

The purpose of this work was to evaluate solid lipid nanoparticles (SLNs) as a long acting injectable drug delivery platform for intramuscular and subcutaneous administration. SLNs were developed with a low (unsaturated) and high (supersaturated) drug concentration at equivalent lipid doses. The impact of the drug loading as well as the administration route for the SLNs using two model compounds with different physicochemical properties were explored for their in vitro and in vivo performance. Results revealed that drug concentration had an influence on the particle size and entrapment efficiency of the SLNs and, therefore, indirectly an influence on the Cmax/dose and AUC/dose after administration to rats. Furthermore, the in vitro drug release was compound specific, and linked to the affinity of the drug compounds towards the lipid matrix and release medium. The pharmacokinetic parameters resulted in an increased tmax, t1/2 and mean residence time (MRT) for all formulations after intramuscular and subcutaneous dosing, when compared to intravenous administration. Whereas, the subcutaneous injections performed better for those parameters than the intramuscular injections, because of the higher blood perfusion in the muscles compared with the subcutaneous tissues. In conclusion, SLNs extend drug release, need to be optimized for each drug, and are appropriate carriers for the delivery of drugs that require a short-term sustained release in a timely manner.

Effects of Esomeprazole on Pharmacokinetic Behavior of Sulfasalazine in Rats / 中国药房

OBJECTIVE：To develop a metho d for determining the plasma concentration of sulfasalazine （SSZ）metabolite sulfapyridine（SP）in rats ，and to investigate the effects of esomeprazole （ESOM）on the pharmacokinetic behavior of SSZ in rats. METHODS：Male SD rats were randomly divided into SSZ group and SSZ+ESOM group ，with 6 rats in each group. SSZ+ESOM group were given Esomeprazole enteric-coated tablets [ 90 mg/（kg·d）] intragastrically for 14 days. On the 15th day ，the rats in 2 groups were given Sulfasalazine enteric coated tablets （90 mg/kg）intragastrically，and blood sample was collected from the inner canthus at 0.5，1，1.5，2，3，4，6，8，10，12，24，36，48，72 h after administration. After protein precipitation with methanol ， using diazepam as internal standard ，Agilent XDR-C 18 column was adopted with methanol- 0.1％ formic acid solution （gradient elution）as mobile phase. The concentration of SSZ metabolite SP in plasma was determined by LC-MS/MS. The pharmacokinetic parameters were calculated by using DAS 3.0.1 software and compared between 2 groups. RESULTS ：The linear range of SP were 2-1 000 ng/mL. The methodology met the requirements of Chinese Pharmacopeia . There was no statistical significance in pharmacokinetic parameters of SP between 2 groups，such as AUC 0－t，tmax，t1/2z，cmax，MRT0－t（P＞0.05）. CONCLUSIONS ：The established method is simple ，rapid and sensitive ；it can be used for the concentration determination of SSZ metabolite SP in plasma. ESOM has no significant effect on the pharmacokinetic behavior of SSZ in rats.

Fabrication of a novel drug-resin combination device for controlled release of dextromethorphan hydrobromide.

The implimentation of newer technologies in drug delivery system have always been the focus of pharmaceutical scientists with advancement of technologies. In this investigation, a novel controlled-release drug-resin combination device (DRC) was designed using dental resin to control the release of dextromethorphan hydrobromide (DH). The influence of different factors on in-vitro drug release were investigated. A Box-Behnken design was used to select the optimized DRC formulation. The optimized DH loaded DRC (DH-DRC) was prepared using 59.88% of PEG400, 16 mg of dental resin and 6.64 mg of sodium chloride (NaCl). The DH releases at 2 h, 4 h and 8 h of the optimized formulation were significantly close to the predicted responses. The pharmacokinetic study in rabbits showed DH-DRC had prolonged tmax and apparently reduced Cmax compared with commercial tablets and the AUC0-24h of DH-DRC was slightly higher than commercial tablets. This study confirmed the novel DRC could control the release of drug. It concluded that DRC would be a promising and alternative approach for the development of controlled release dosage form.

Preparation and Release Profiles in Vitro/Vivo of Galantamine Pamoate Loaded Poly (Lactideco-Glycolide) (PLGA) Microspheres.

Patient's poor compliance and the high risk of toxic effects limit the clinical use of galantamine hydrobromide. To overcome these drawbacks, the sustained-release galantamine pamoate microspheres (GLT-PM-MS) were successfully developed using an oil/water emulsion solvent evaporation method in this study. Physicochemical properties of GLT-PM-MS were carefully characterized, and the in vitro and in vivo drug release behaviors were well studied. Results showed that the morphology of optimized microspheres were spherical with smooth surfaces and core-shell interior structure. Mean particle size, drug loading and entrapment efficiency were 75.23 ± 1.79 µm, 28.01 ± 0.81% and 87.12 ± 2.71%, respectively. The developed GLT-PM-MS were found to have a sustained release for about 24 days in vitro and the plasma drug concentration remained stable for 17 days in rats. These results indicated that GLT-PM-MS could achieve the sustained drug release purpose and be used in clinical trial.

Observation on efficacy, pharmacokinetic behaviors and safety of new modified RNA oligonucleotide targeting Foxo-1 via two routes of administration / 药学学报

Foxo-1 plays an important role in development of muscle atrophy, serving as a potential target for therapeutic treatment of the disease. In this study, the Foxo-1 mRNA was targeted by a Foxo-1 specific RNA oligonucleotide modified by 2'-O-methyl and with a butanol tag at the 3'-end. To understand the in vivo significance of new modified RNA oligos, efficacy, pharmacokinetic and safety profiles of the new modified RNA oligonucleotide targeting Foxo-1 were evaluated in mice. All experimental protocols were approved by the Animal Ethics Committee of Institute for Nutrition and Health, Chinese Center for Disease Control and Prevention. The results showed that different doses of the RNA oligonucleotide can reduce the expression of Foxo-1 in mice by two routes of administration, leading to an increase in skeletal muscle mass of the mice. The results of pharmacokinetic evaluation showed that the plasma disappearance curve for the RNA oligonucleotide could be described by a two-compartmental model. The results of safety evaluation showed that no obvious adverse effects on renal and hepatic functions, nor on hematological parameters by intravenous or oral administration of the RNA oligo with a maximum dose of 30 mg·kg-1. Histopathology also did not reveal any significant changes in the morphology of the organs studied. In conclusion, the new modified RNA oligo is safe and effective in mice, providing experimental evidence supporting the significance for its clinical application.

Propylene glycol-embodying deformable liposomes as a novel drug delivery carrier for vaginal fibrauretine delivery applications.

The purpose of this work was to develop and characterize the fibrauretine (FN) loaded propylene glycol-embodying deformable liposomes (FDL), and evaluate the pharmacokinetic behavior and safety of FDL for vaginal drug delivery applications. FDL was characterized for structure, particle size, zeta potential, deformability and encapsulation efficiency; the ability of FDL to deliver FN across vagina tissue in vitro and the distribution behavior of FN in rat by vaginal drug delivery were investigated, the safety of FDL to the vagina of rabbits and rats as well as human vaginal epithelial cells (VK2/E6E7) were also evaluated. Results revealed that: (i) the FDL have a closed spherical shape and lamellar structure with a homogeneous size of 185±19nm, and exhibited a negative charge of -53±2.7mV, FDL also have a good flexibility with a deformability of 92±5.6 (%phospholipids/min); (ii) the dissolving capacity of inner water phase and hydrophilicity of phospholipid bilayers of deformable liposomes were increased by the presence of propylene glycol, this may be elucidated by the fluorescent probes both lipophilic Nile red and hydrophilic calcein that were filled up the entire volume of the FDL uniformly, so the FDL with a high entrapment capacity (were calculated as percentages of total drug) for FN was 78±2.14%; (iii) the permeability of FN through vaginal mucosa was obviously improved by propylene glycol-embodying deformable liposomes, no matter whether the FN loaded in liposomes or not, although FN loaded in liposomes caused the highest permeability and drug reservoir in vagina; (iv) the FN mainly aggregated in the vagina and uterus, then the blood, spleen, liver, kidney, heart and lungs for vaginal drug delivery, this indicating vaginal delivery of FDL have a better 'vaginal local targeting effect'; and (v) the results of safety evaluation illustrate that the FDL is non-irritant and well tolerated in vivo, thereby establishing its vaginal drug delivery potential. These results indicate that the propylene glycol-embodying deformable liposomes may be a promising drug delivery carrier for vaginal delivery of fibrauretine.