Pharmacokinetics and tissue distribution study of schisandrin B in rats by ultra-fast liquid chromatography with tandem mass spectrometry

Bioavailability and interactions of schisandrin B with 5-fluorouracil in a xenograft mouse model of colorectal cancer

Schisandrin B (Sch B) is a predominant bioactive lignan from the fruit of a Chinese medicine food homology plant, Schisandra chinensis. Previously, we observed potent anti-tumor effect of Sch-B in colorectal cancer (CRC) and enhanced chemotherapy efficacy with fluorouracil (5-FU). However, their bioavailability and reciprocal interactions under CRC conditions are unclear. In this study, we first compared the bioavailability, metabolism and tissue distribution of Sch-B between non-tumor-bearing and xenograft CRC tumor-bearing mice. Next, we examined SchB-5-FU interactions via investigating alterations in drug metabolism and multidrug resistance. Using a validated targeted metabolomics approach, five active metabolites, including Sch-B and fluorodeoxyuridine triphosphate, were found tumor-accumulative. Co-treatment resulted in higher levels of Sch-B and 5-FU metabolites, showing improved phytochemical and drug bioavailability. Multidrug resistance gene (MDR1) was significantly downregulated upon co-treatment. Overall, we demonstrated the potential of Sch-B to serve as a promising chemotherapy adjuvant via improving drug bioavailability and metabolism, and attenuating MDR.

Safety and efficacy of a feed additive consisting of a tincture derived from the dried fruit of Schisandra chinensis (Turcz.) Baill. (omicha tincture) for poultry, horses, dogs and cats (FEFANA asbl)

Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety and efficacy of a tincture from the dried fruit of Schisandra chinensis (Turcz.) Baill. (omicha tincture), when used as a sensory additive in feed for horses, cats, dogs, and in feed and in water for drinking for poultry. The product is a water/ethanol (55:45 v/v) solution, with a dry matter content of not more than 4% (w/w) and a content of 0.01%-0.15% (w/w) for the sum of schisandrin and deoxyschisandrin. The Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) concluded that omicha tincture is safe at the following concentrations in complete feed: 16 mg/kg for turkeys for fattening, 12 mg/kg for chickens for fattening and other poultry for fattening or reared for laying/reproduction, 18 mg/kg for laying hens and other laying/reproductive birds, 56 mg/kg for dogs and 47 mg/kg for horses and cats. The additive is considered safe for consumers when used up to the highest safe level in feed for poultry species and horses. Omicha tincture should be considered as irritants to skin and eyes, and as dermal and respiratory sensitisers. The use of omicha tincture as a flavour in feed for poultry species and horses was not considered to be a risk to the environment. Since it was recognised that the fruit of S. chinensis can influence sensory properties of feedingstuffs, no further demonstration of efficacy was considered necessary for the tincture under assessment.

In Silico Analysis, Anticonvulsant Activity, and Toxicity Evaluation of Schisandrin B in Zebrafish Larvae and Mice

The aim of this study is to evaluate the anticonvulsant potential of schisandrin B, a main ingredient of Schisandra chinensis extracts. Schisandrin B showed anticonvulsant activity in the zebrafish larva pentylenetetrazole acute seizure assay but did not alter seizure thresholds in the intravenous pentylenetetrazole test in mice. Schisandrin B crosses the blood-brain barrier, which we confirmed in our in silico and in vivo analyses; however, the low level of its unbound fraction in the mouse brain tissue may explain the observed lack of anticonvulsant activity. Molecular docking revealed that the anticonvulsant activity of the compound in larval zebrafish might have been due to its binding to a benzodiazepine site within the GABAA receptor and/or the inhibition of the glutamate NMDA receptor. Although schisandrin B showed a beneficial anticonvulsant effect, toxicological studies revealed that it caused serious developmental impairment in zebrafish larvae, underscoring its teratogenic properties. Further detailed studies are needed to precisely identify the properties, pharmacological effects, and safety of schisandrin B.

Reducing oxidative stress may be important for treating pirarubicin-induced cardiotoxicity with schisandrin B

The cardiotoxicity of pirarubicin (THP) seriously affects its clinical application, which cannot be ignored. The antioxidant effect of schisandrin B (SchB) has been extensively reported in the context of dietotherapy. However, whether this antioxidant effect can protect the heart from THP damage remains unknown. The aim of the present study was to investigate whether the antioxidant effect of SchB can antagonize the cardiotoxicity of THP. Changes in electrocardiogram (ECG), echocardiography and serum lactate dehydrogenase, brain natriuretic peptide, creatine kinase MB and cardiac troponin T levels were used to detect the degree of cardiac damage. The levels of superoxide dismutase (SOD), malondialdehyde, catalase and total antioxidant capacity in the serum and heart were measured to observe the oxidative stress state of rats. Primary cardiomyocytes were cultured, and cell viability and reactive oxygen species (ROS) production were detected. Western blotting was used to detect the expression levels of SOD2, NOX2, pro/cleaved-caspase3 and Bcl-2/Bax in heart tissue and primary cardiomyocytes to verify the related signaling pathways. THP-treated rats showed a range of cardiac damage, including an abnormal ECG, echocardiography and myocardial enzymes. In the cellular experiments, cell viability decreased and ROS increased. However, this damage was alleviated after SchB treatment. Further studies demonstrated that SchB antagonized THP cardiotoxicity via its antioxidant effect. In conclusion, SchB protects the heart from THP damage in rats, and the mechanism may be closely associated with its antioxidant effect.

Antioxidant Effects of Schisandra chinensis Fruits and Their Active Constituents

Schisandra chinensis Turcz. (Baill.) fruits, their extracts, and bioactive compounds are used in alternative medicine as adaptogens and ergogens protecting against numerous neurological, cardiovascular, gastrointestinal, liver, and skin disorders. S. chinensis fruit extracts and their active compounds are potent antioxidants and mitoprotectors exerting anti-inflammatory, antiviral, anticancer, and anti-aging effects. S. chinensis polyphenolic compounds-flavonoids, phenolic acids and the major constituents dibenzocyclooctadiene lignans are responsible for the S. chinensis antioxidant activities. This review will focus on the direct and indirect antioxidant effects of S. chinensis fruit extract and its bioactive compounds in the cells during normal and pathological conditions.

Development of a sensitive and rapid UHPLC-MS/MS method for simultaneous quantification of nine compounds in rat plasma and application in a comparative pharmacokinetic study after oral administration of Xuefu Zhuyu Decoction and nimodipine

Xuefu Zhuyu Decoction (XFZYD) is a traditional Chinese medicine prescription used for the clinical treatment of traumatic brain injury (TBI). The purpose of this work was to develop a sensitive and rapid UHPLC-MS/MS method to simultaneously study the pharmacokinetics of nimodipine and eight components of XFZYD, namely, amygdalin, hydroxysafflor yellow A, rutin, liquiritin, narirutin, naringin, neohesperidin and saikosaponin A, in rats with and without TBI. Multiple reaction monitoring was highly selective in the detection of nine analytes and the internal standard without obvious interference. The calibration curves displayed good linearity (r > 0.99) over a wide concentration range. The mean absolute recoveries of the nine analytes were 85-106%, and all matrix effects were in the range 80-120%. The intra- and inter-day precision and accuracy were acceptable (RSD, <15%; RE%, ±20%). The validated method was successfully applied to compare the pharmacokinetics in four experimental groups, including control rats orally administered XFZYD and TBI model rats orally administered XFZYD, XFZYD and nimodipine, or nimodipine alone. The results showed that herb-drug interactions occurred between XFZYD and nimodipine in the treatment of TBI, nimodipine affected the pharmacokinetics of XFZYD, and XFZYD affected the absorption, distribution and excretion of nimodipine in vivo.

Simultaneous extraction of several targets by using non-toxic dual template molecularly imprinted polymers in vivo and in vitro

In this report, a non-toxic Dual Template Molecularly Imprinted Polymers (DMIPs) was synthesized with quercetin and schisandrin b as template molecules, using deep-eutectic solvents as functional monomers for the first time. The DMIPs were used to efficiently and simultaneously enrich quercetin and schisandrin b from the mixed crude extracts of penthorum and schisandra. The results indicated that the DMIPs exhibited rapid adsorption kinetics (80 min for adsorption equilibrium) and high selectivity. The largest adsorbing capacities to quercetin and schisandrin b were 23.58 mg/g and 41.64 mg/g, respectively. After presaturation with quercetin and schisandrin b, the nontoxic saturated DMIPs were fed to the mice. Blood samples of the mice were taken and both quercetin and schisandrin b were successfully detected. The pharmacokinetics of quercetin and schisandrin b were similar to reports in the literature where mice were directly fed with botanicals. Our study provides a reliable protocol such that DMIPs can be used to separate and enrich several target molecules simultaneously from complex biological systems. Our findings suggested that the DMIPs have potential application as a drug delivery system of compound herbal formulas.

Pharmacokinetics and tissue distribution study of prucalopride in rats by ultra high performance liquid chromatography with tandem mass spectrometry

A sensitive, reliable and high throughput ultra high performance liquid chromatography with tandem mass spectrometry (UPLC-MS/MS) method was developed and validated for the determination of prucalopride in rat plasma and various tissues (including heart, liver, spleen, lung, kidney, stomach,small intestine, large intestine, cecum, cerebrum, cerebellum, and ovary). The plasma and tissues samples were treated by protein precipitation with acetonitrile using carbamazepine as an internal standard (IS). Chromatographic separation was performed on a Waters ACQUITY UPLC^® HSS C18 column (2.1mm×50mm, 1.8μm) with a gradient mobile phase consisting of acetonitrile-water (containing 0.1% formic acid) as mobile phase at a flow rate of 0.2mL/min. The quantification was performed by multiple reactions monitoring mode with m/z 367.99→195.89 for prucalopride and m/z 236.97→194.04 for carbamazepine on a Waters Xevo TQD mass spectrometry equipped with electrospray ionization (ESI) source. The calibration curve was linear in the range of 0.1-100ng/mL for plasma and various tissues (r≥0.99) with a lower limit of quantification of 0.1ng/mL. The recoveries obtained for prucalopride were more than 85%. The validated method was successfully applied to the pharmacokinetics and tissue distribution study of prucalopride after oral administration to rats. The pharmacokinetic parameters were demonstrated as followed: the time to reach peak concentration (T_max) was 1.0h, and the peak concentration (C_max) was 21.71±4.28ng/mL, the half-life (t_1/2) was 18.21±0.69h, and the area under the curve (AUC) was 59.30±9.43ngh/mL. Tissue distribution showed the highest level was observed in stomach and intestine, then in liver, which indicated that prucalopride was absorbed firstly in stomach and intestine, and mainly accumulated in liver. It was also the first study to investigate the tissue distribution of prucalopride in rats following oral administration.

Distribution, Metabolism and Toxic Effects of Beta-Cypermethrin in Lizards (Eremias argus) Following Oral Administration

Beta-cypermethrin (BCYP), a synthetic pyrethriod (PYR) pesticide which is a mixture of the alpha- and theta- cypermethrin, have been reported various toxicological profiles to non-target organisms. But little is known about assimilation, accumulation and toxic effects of BCYP in reptiles. The present study firstly elucidated absorption, tissue distribution, excretion of BCYP in Eremias argus . Treated group were administered orally with BCYP 20mg/kg body weight (bw) dissolved in corn oil. Neurotoxicity was observed at 24h after gavage, and the poisoning symptom ameliorated at 72h. The changes of BCYP concentration depended on degradation time and tissues. Lizards had a strong capacity to eliminate BCYP with different tissue distribution. The tissues concentration of BCYP from high to low were intestine, stomach, heart, kidney, blood, lung, liver and brain. Bimodal phenomena were observed in lung, liver and kidney. These results may be due to the activities of enzymes, circadian rhythm, and enterohepatic circulation in lizards. Based on the results of organ coefficient and histopathology analysis in liver, the liver was confirmed as the main target organ.

Enhanced oral absorption of saquinavir mediated by PEGylated solid lipid nanoparticles

PEGylated solid lipid nanoparticles containing saquinavir exhibited higher relative bioavailability which increased with enhancing of the polyethylene glycol content in the nanoparticles.

Sample preparation for liquid chromatographic analysis of phytochemicals in biological fluids

INTRODUCTION

Natural products have been used traditionally for the treatment and prevention of diseases for thousands of years and are nowadays consumed as dietary supplements and herbal medicine. To ensure the safe and effective use of these herbal products, information about bioavailability of active compounds in plasma or target tissues should be provided via validated analytical methods combined with appropriate sampling methods.

OBJECTIVE

To provide comprehensive and abridged information about sample preparation methods for the quantification of phytochemicals in biological samples using liquid chromatography analysis.

METHODS

Sample pre-treatment procedures used in analytical methods for in vivo pharmacokinetic studies of natural compounds or herbal medicines were reviewed. These were categorised according to the biological matrices (plasma, bile, urine, faeces and tissues) and sample clean-up processes (protein precipitation, liquid-liquid extraction and solid-phase extraction).

RESULTS

Although various kinds of sample pre-treatment methods have been developed, liquid-liquid extraction is still widely used and solid-phase extraction is becoming increasingly popular because of its efficiency for extensive clean up of complex matrix samples. However, protein precipitation is still favoured due to its simplicity.

CONCLUSION

Sample treatment for phytochemical analysis in biological fluids is an indispensable and critical step to obtain high quality results. This step could dominate the overall analytical process because both the duration of the process as well as the reliability of the data depend in large part on its efficiency. Thus, special attention should be given to the choice of a proper sample treatment method that targets analytes and their biomatrix.

A sensitive liquid chromatography-tandem mass spectrometry method for pharmacokinetics and tissue distribution of nuciferine in rats

Nuciferine is an important drug candidate for the treatment of obesity-related diseases. However, few investigations have been conducted about the pharmacokinetics and tissue distribution of nuciferine to better understand its behavior and action mechanism in vivo. Thus, a sensitive and reliable liquid chromatography with tandem mass spectrometry (HPLC-MS/MS) method was established and validated for the quantification of nuciferine in rat plasma and tissue samples. The validated method was successfully applied to the pharmacokinetic and tissue distribution study of nuciferine in rats. One-compartmental pharmacokinetic parameters indicated that nuciferine had rapid distribution, extensive tissue uptake, and poor absorption into systemic circulation. The values of absolute bioavailability were (3.8±1.4)%, (4.2±1.3)% and (3.9±1.0)% after oral administration of 2.0, 5.0 and 10.0mg/kg nuciferine and intravenous administration of 0.2mg/kg nuciferine in rats. The results of the tissue distribution study suggested that nuciferine was distributed into the brain, liver and adipose tissue after intravenous administration. In conclusion, the present study may provide a material basis for study of the pharmacological action of nuciferine in the treatment of obesity, and meaningful insights into further study on dosage modification.

Ultra-performance liquid-chromatography with tandem mass spectrometry for rapid analysis of pharmacokinetics, biodistribution and excretion of schisandrin after oral administration of Shengmaisan

This study aimed to investigate the in vivo behaviors of the main components in traditional Chinese medicine (TCM) fomulae. The plasma pharmacokinetics, tissue distribution and excretion of the main component-schisandrin in rats after oral administration of a classical TCM prescription, shengmaisan (SMS), were studied by a developed and validated UPLC-MS/MS method. The separation of schisandrin was achieved on a UPLC HSS T3 column with a mobile phase consisting of acetonitrile and water at a flow rate of 0.5 mL/min by linear gradient elution. The MS/MS detection was carried out by monitoring the fragmentation of m/z 415.22 → 384.26 for schisandrin on a triple quadrupole mass spectrometer. The result showed that the method was suitable for the quantification of schisandrin in plasma, tissue and excreta samples with satisfactory selectivity, precision, accuracy, sensitivity, linearity and recovery. Pharmacokinetic results showed a rapid absorption phase with the mean Tmax of 0.17 h and a relatively slow elimination proceeding with a half-life (T1/2 ) of 5.24 ± 1.28 h. The tissue distribution showed the maximum concentration distributions of schisandrin after oral administration of SMS were in the order of small intestine > large intestine > lung > liver > kidney > spleen > heart > brain. Only 0.005-0.006% of schisandrin was recovered in feces and was not detected in urine.