Multicomponent qualitative and quantitative analysis of Farfarae Flos in serum using UHPLC-Q TOF-MS.

Farfarae Flos is a traditional herb widely employed for treating coughs, bronchitis, and asthmatic disorders. In the current study, we utilized SWATH and IDA data acquisition modes in combination with multiple data processing techniques to identify Farfarae Flos metabolites in mice serum. A total of 56 compounds were characterized, including 31 phenolic acids, 13 flavonoids, 11 sesquiterpenoids and 1 alkaloid. Further quantitative analysis was conducted on 12 absorbed metabolites, utilizing a newly developed and rigorously validated analytical method. Our approach demonstrated an acceptable level of specificity, accuracy, precision, and stability. When applied to compare the serum of mice treated with FF, all 12 metabolites showed the highest concentration at 0.5 h. Overall, this study presented a novel strategy for unraveling the active compounds of FF via serum pharmacochemistry analysis, which made a foundation for exploring the pharmacodynamic material basis of FF.

Comparative Pharmacokinetics of Curcuminoids from Water-Dispersible Turmeric Extract Against a Curcuminoids-Piperine Combination: An Open-Label, Randomized, Balanced, 2-Treatment, 2-Sequence, 2-Period Crossover Study.

Objective: Curcuminoids, the major component of which is curcumin, are natural polyphenolic compounds from the rhizome of Curcuma longa Linn. and possess extensive biopharmacological properties that are limited in humans due to poor bioavailability. Currently, most commercial bioavailable turmeric extracts use synthetic excipients or the addition of piperine to enhance bioavailability, and are needed in multiple daily doses to achieve clinical efficacy. This study was conducted to compare the bioavailability of a natural, water-dispersible turmeric extract containing 60% natural curcuminoids, the test product, WDTE60N (1 × 250 mg per day), with the reference product, turmeric extract capsules (500 mg curcuminoids and 5 mg piperine, CPC; 3 × 500 mg per day). Methods: Sixteen healthy adult male subjects fasted overnight for 10 hours and then were dosed with either one capsule of the test product WDTE60N or three capsules of reference product CPC orally (One capsule administered at every 6 hours interval i.e. at 0.00 hrs, 6.00 hrs and at 12.00 hrs) in each study period. Blood sampling before and after dosing was carried out at defined time points at -12.00, -02.00, 00.00 (within 10 minutes prior to dosing) hours in morning before dosing and post-dose (First dose) at 00.50, 01.00, 02.00, 03.00, 04.00, 05.00, 06.50, 07.00, 08.00, 09.00, 10.00, 11.00, 12.50, 13.00, 14.00, 16.00, 18.00, 20.00 and 24.00 hours in each period. Plasma concentration of curcuminoids was determined using a validated liquid chromatography with tandem mass spectrometry bioanalytical method. Results: The Cmax (GLSM) for the test product WDTE60N was observed to be 74.56 ng/mL; and same for the reference CPC was 22.75 ng/mL. AUC0-t (GLSM) for test WDTE60N was 419.00 h∙ng/mL; and for reference CPC it was 359.86 h∙ng/mL for total curcuminoids. Conclusion: The test formulation WDTE60N showed improved relative absorption and equivalent exposure at a 10-fold-lower dose of actives than the reference formulation CPC.

Formation of multiple ion types during MALDI imaging mass spectrometry analysis of Mitragyna speciosa alkaloids in dosed rat brain tissue.

Mitragyna speciosa, more commonly known as kratom, has emerged as an alternative to treat chronic pain and addiction. However, the alkaloid components of kratom, which are the major contributors to kratom's pharmaceutical properties, have not yet been fully investigated. In this study, matrix-assisted laser desorption/ionization (MALDI) imaging mass spectrometry was used to map the biodistribution of three alkaloids (corynantheidine, mitragynine, and speciogynine) in rat brain tissues. The alkaloids produced three main ion types during MALDI analysis: [M + H]+, [M - H]+, and [M - 3H]+. Contrary to previous reports suggesting that the [M - H]+ and [M - 3H]+ ion types form during laser ablation, these ion types can also be produced during the MALDI matrix application process. Several strategies are proposed to accurately map the biodistribution of the alkaloids. Due to differences in the relative abundances of the ions in different biological regions of the tissue, differences in ionization efficiencies of the ions, and potential overlap of the [M - H]+ and [M - 3H]+ ion types with endogenous metabolites of the same empirical formula, a matrix that mainly produces the [M + H]+ ion type is optimal for accurate mapping of the alkaloids. Alternatively, the most abundant ion type can be mapped or the intensities of all ion types can be summed together to generate a composite image. The accuracy of each of these approaches is explored and validated.

Determination of alkaloid-inspired molecule vindeburnol in rabbit plasma by UPLC-HRMS and its application to pharmacokinetic studies and preliminary metabolite identification.

The eburnamine-vincamine alkaloids exhibit a range of pharmacological activities. There is a limited understanding of the pharmacokinetics and pharmacodynamics of vindeburnol, a synthetic derivative of this chemical class of alkaloids. A fast and reliable UPLC-HRMS method was developed and validated to quantify vindeburnol in Soviet Chinchilla rabbit plasma from pharmacokinetics studies. An ultra-performance liquid chromatography system equipped with a Waters Acquity UPLC HSS T3 column was used for chromatographic separation by gradient elution with 0.1% (v/v) formic acid in water and acetonitrile. An Impact II QqTOF high-resolution mass spectrometer equipped with an Apollo II electrospray ionization source was used for analysis in positive mode; the ions [M+H]+m/z 269.1648 ± 0.003 and m/z 351.2067 ± 0.003 were monitored for vindeburnol and internal standard (vinpocetine), respectively. Preliminary metabolite profiling was also performed, and the pharmacokinetics of the identified metabolites were evaluated. The mean retention times for vindeburnol and vinpocetine were 2.0 and 3.5 min. The UPLC-HRMS method was validated with accuracy and precision within the 15% acceptance limit (8.2% and 11.0%, respectively). The mean extraction recovery value of vindeburnol from rabbit plasma was 77%. Pharmacokinetic evaluation of vindeburnol revealed that the compound is distributed rapidly with a short elimination half-life. Vindeburnol undergoes extensive first-pass metabolism and is metabolized into hydroxyvindeburnol and vindeburnol glucuronide.

[Pharmacokinetics and tissue distribution of four alkaloids in Ermiao Pills and Sanmiao Pills in normal and arthritic model rats].

This work aimed to investigate the differences of pharmacokinetics and tissue distribution of four alkaloids in Ermiao Pills and Sanmiao Pills in normal and arthritic model rats. The rat model of arthritis was established by injecting Freund's complete adjuvant, and ultra-high performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS) in the positive ion multiple reaction monitoring(MRM) mode was used for the determination of four alkaloids in plasma and tissues of normal and arthritic rats after administration of Ermiao Pills and Sanmiao Pills, respectively. The differences in pharmacokinetics and tissue distribution of the four active components were compared, and the effect of Achyranthis Bidentatae Radix on the major components of Sanmiao Pills was explored. This study established an UPLC-MS/MS for simultaneous determination of four alkaloids, and the specificity, linearity, accuracy, precision, and stability of this method all met the requirements. Pharmacokinetics study found that as compared with normal rats, the AUC and C_(max) of phellodendrine, magnoflorine, berberine and palmatine in model rats were significantly decreased after administration of Ermiao Pills, the clearance rate CL/F was significantly increased, and the distribution and tissue/plasma concentration ratio of the four alkaloids in the liver, kidney, and joint were significantly reduced. Achyranthis Bidentatae Radix increased the AUC of phellodendrine, berberine, and palmatine, reduced the clearance rate, and significantly increased the distribution of the four alkaloids in the liver, kidney, and joints in arthritic rats. However, it had no significant effect on the pharmacokinetics and tissue distribution of the four alkaloids in normal rats. These results suggest that Achyranthis Bidentatae Radix may play a guiding role in meridian through increasing the tissue distribution of effective components in Sanmiao Pills under arthritis states.

Complexation of Apigenin and Oxymatrine Leading to Enhanced Anti-inflammatory Activity.

Apigenin (APG) is a well-known dietary flavonoid with multiple bioactivities, but its poor aqueous solubility may result in low oral bioavailability and thus compromised therapeutic effects. In the present study, APG was complexed with oxymatrine (OMT), a natural quinolizidine alkaloid, for enhanced anti-inflammatory activity, and the related mechanisms in the interaction of APG with OMT were investigated. Fourier transform-infrared spectroscopy, fluorescence spectroscopy, Raman spectroscopy, and proton nuclear magnetic resonance spectroscopy characterizations demonstrated the occurrence of an APG-OMT complex formed at a molar ratio of 1:2. Then, molecular dynamics simulations and quantum chemical calculations were utilized to elucidate that hydrogen bonding, van der Waals forces, and hydrophobic effects were the main forces acting in the formation of the APG-OMT complex. Pharmacokinetic studies in rats demonstrated that the oral bioavailability of APG in the APG-OMT complex was significantly higher than that of APG alone. Finally, bioactivity evaluation in the lipopolysaccharide-induced acute inflammatory injury mouse models showed that the APG-OMT complex exhibited more potent anti-inflammatory effects than APG alone. This study confirmed that APG and OMT exerted enhanced anti-inflammatory effects through self-complexation, which may provide a novel strategy for improving the bioavailability and bioactivity of natural product mixtures.

HPLC-MS/MS analysis of primary alkaloids in rat plasma after oral administration of "Nux vomica - Glycyrrhiza glabra decoction": A pharmacokinetic study.

ETHNOPHARMACOLOGICAL RELEVANCE: Decoction is the most common form of administering traditional Chinese medicine (TCM). During the preparation of decoction, the high temperature and complex chemical environment result in the formation of complex and multiple phases. The differences in drug components in different phases induce gastrointestinal absorption and physiological response. Nux vomica (Strychnos nux-vomica L) is a typical toxic TCM used in China, with remarkable pharmacological activity. In order to reduce its toxicity, nux vomica (NV) is often decocted with Glycyrrhiza glabra (GG) in clinic, and the detoxification mechanism has always been the focus of research interest. Most studies investigated the compatibility of NV-GG, but the in vivo behavior of individual constituents based on phase state has yet to be elucidated. AIM OF THE STUDY: To investigate the pharmacokinetic behavior of typical toxic components in different phase states of "NV-GG decoction" in rat plasma. MATERIALS AND METHODS: The sediment, suspension, colloid and true solution of "NV-GG decoction" was obtained via physical methods. The main components in different phase states were analyzed via reliable UFLC-Q-TOF-MS high-resolution mass spectrometry. A rapid and accurate HPLC-qqq-MS/MS method was established and validated for accurate determination of brucine and strychnine levels in plasma, followed by pharmacokinetic evaluation of different phase states of "NV-GG decoction" in rats. Kinetex F5 100A (50 mm × 3.0 mm, 2.6 µm) column was used for chromatographic separation. Aqueous solution containing acetonitrile and 0.1% formic acid was used as the mobile phase, followed by gradient elution at 0.4 mL/min. Mass spectra were detected by electrospray ionization (ESI) multiple reaction monitoring (MRM) in positive ion mode. RESULTS: Fifteen different alkaloids were detected in different phase states of "NV-GG decoction". Strychnine and brucine, which are toxic components with high content, were selected for quantitative analysis. The established UPLC-qqq-MS/MS method is accurate and reliable with a good linearity (R2 > 0.99) in the respective concentration range, satisfying the quantitative requirements. The pharmacokinetic parameters of different phase states of rats differed significantly after gavage. The deposition phase was the most prominent. The index components showed higher Cmax, AUC0 and Tmax, while the T1/2, MRT, V/F and CL/F were the smallest, with a relatively slow plasma clearance rate in rats. The true solution group showed the lowest Tmax and the fastest absorption. CONCLUSION: This method has been successfully utilized to study the pharmacokinetics of different phase states of "NV-GG decoction". Among the four phases, the deposition phase contributed to a large proportion of the in vivo kinetic behavior similar to that of sustained-release preparations, with slow absorption of toxic components and prolonged peak time. The pharmacokinetic parameters and plasma concentration-time curves of each phase can be used to study toxicity reduction of NV-GG and increase its biocompatibility.

Mesembryanthemum tortuosum L. alkaloids modify anxiety-like behaviour in a zebrafish model.

ETHNOPHARMACOLOGICAL RELEVANCE: Mesembryanthemum tortuosum L. (previously known as Sceletium tortuosum (L.) N.E. Br.) is indigenous to South Africa and traditionally used to alleviate anxiety, stress and depression. Mesembrine and its alkaloid analogues such as mesembrenone, mesembrenol and mesembranol have been identified as the key compounds responsible for the reported effects on the central nervous system. AIM OF THE STUDY: To investigate M. tortuosum alkaloids for possible anxiolytic-like effects in the 5-dpf in vivo zebrafish model by assessing thigmotaxis and locomotor activity. MATERIALS AND METHODS: Locomotor activity and reverse-thigmotaxis, recognised anxiety-related behaviours in 5-days post fertilization zebrafish larvae, were analysed under simulated stressful conditions of alternating light-dark challenges. Cheminformatics screening and molecular docking were also performed to rationalize the inhibitory activity of the alkaloids on the serotonin reuptake transporter, the accepted primary mechanism of action of selective serotonin reuptake inhibitors. Mesembrine has been reported to have inhibitory effects on serotonin reuptake, with consequential anti-depressant and anxiolytic effects. RESULTS: All four alkaloids assessed decreased the anxiety-related behaviour of zebrafish larvae exposed to the light-dark challenge. Significant increases in the percentage of time spent in the central arena during the dark phase were also observed when larvae were exposed to the pure alkaloids (mesembrenone, mesembrenol, mesembrine and mesembrenol) compared to the control. However, mesembrenone and mesembranol demonstrated a greater anxiolytic-like effect than the other alkaloids. In addition to favourable pharmacokinetic and physicochemical properties revealed via in silico predictions, high-affinity interactions characterized the binding of the alkaloids with the serotonin transporter. CONCLUSIONS: M. tortuosum alkaloids demonstrated an anxiolytic-like effect in zebrafish larvae providing evidence for its traditional and modern day use as an anxiolytic.

Comparative pharmacokinetics, intestinal absorption and urinary excretion of six alkaloids from herb pair Phellodendri Chinensis cortex-Atractylodis Rhizoma.

Phellodendri Chinensis Cortex (PCC) and Atractylodis Rhizoma (AR) are frequently used as herb pair to treat eczema and gout owing to their synergistic effects. Alkaloids are the major ingredients from PCC and the effect of their combination on the in vivo processing of alkaloids remains unclear. In this study, a simple and reliable UPLC-MS/MS method for simultaneous determination of six alkaloids in rat plasma was developed. This method was applied to a comparative pharmacokinetic study between PCC and PCC-AR in rats. Effect of AR on absorption of alkaloids was investigated by a single-pass intestinal perfusion study. The effect of AR on urinary excretion of alkaloids was studied. Pharmacokinetic studies showed that the values of rea under the concentration-time curve of phellodendrine, magnoflorine and palmatine were greater in the PCC-AR group than in the PCC group. The intestinal absorptive parameters absorption rate constant and effective permeability of phellodendrine and jatrorrhizine in PCC-AR groups were higher than those in the PCC group. Urinary excretion studies revealed that the excreted amount of alkaloids in the PCC-AR group was lower than that in the PCC group. The results revealed that the combination of PCC and AR improves intestinal absorption of alkaloids and reduces their urinary excretion, which enhances their systemic exposure. This study may explain the synergetic effects of PCC and AR in clinical applications.

A novel UPLC-MS/MS method for simultaneous quantification of trigonelline, 4-hydroxyisoleucine, and diosgenin from Trigonella foenum-graecum extract: Application to pharmacokinetic study in healthy and type 2 diabetic rats.

Trigonelline (TR), 4-hydroxyisoleucine (4-HI), and diosgenin (DG) are the main bioactives of the purified standardized extract of the popular plant Trigonella foenum-graecum L. (TFG), and it has been proven effective for the treatment of various diseases. However, to the best of our knowledge, no study has investigated the pharmacokinetic parameters of purified standardized T. foenum-graecum extract in normal and diabetic Wistar rats. The present study has developed and validated a rapid, reliable, and sensitive simultaneous ultra-performance liquid chromatography MS method to estimate these bioactives. The chromatographic separation was achieved using methanol, acetonitrile, and 0.1% formic acid with the ideal gradient flow system on a BEH Shield RP 18 column. A positive electrospray ionization mode was selected to estimate m/z values of TR (138.14 > 94.63), 4-HI (148.19 > 74.08), and DG (415.54 > 271.33). The method was robust and reproducible over the linearity range of 60-5000, 6-5000, and 15-5000 ng/mL for TR, 4-HI, and DG, respectively. Using this novel validated method, we investigated the pharmacokinetic parameters of bioactives using Phoenix WinNonlin version 8.0 (Certera) in normal and diabetic rats. The assay was successfully applied for the estimation of pharmacokinetic parameters using noncompartmental analysis. This investigation shows that the absorption rate increased, whereas distribution and elimination processes slowed down in diabetic rats compared with normal rats.

Simultaneous determination of 11 alkaloids in rat plasma by LC-ESI-MS/MS and a pharmacokinetic study after oral administration of total alkaloids extracted from Naucleaofficinalis.

ETHNOPHARMACOLOGICAL RELEVANCE: Nauclea officinalis, a widely used Li medicine, has been used for the treatment of cold, fever, bronchitis, pneumonia, acute tonsillitis, and other ailments. Modern pharmacological studies have demonstrated that the most abundant and active components in N. officinalis are alkaloids, which possess various biological properties such as antibacterial and antitumor activities. AIM OF THE STUDY: To investigate the phytochemical profile of a selected group of alkaloids from the N. officinalis total alkaloids, and to determine the chemical profile of the alkaloids extracted from rat plasma. Further investigation was conducted to determine the pharmacokinetic behaviors of 11 selected major alkaloids, including pumiloside, naucleoxoside A, naucleoxoside B, nauclefine, angustidine, angustoline, (3S,19S)-3,14-dihydroangustoline,[α]D20: (-)191°, (3S,19R)-3,14-dihydroangustoline, [α]D20: (-) 294.7°, strictosamide, angustine, and 3,14-dihydroangustine. MATERIALS AND METHODS: N. officinalis total alkaloids were extracted with 79% ethanol and enriched with AB-8 macroporous resin. The phytochemical profile of alkaloids from the N. officinalis total alkaloids and the chemical profile of the alkaloids extracted from rat plasma were first analyzed by UPLC-Q-TOF-MS/MS. A simple, convenient, and sensitive LC-ESI-MS/MS method was subsequently developed and validated for the simultaneous determination of major active alkaloids in rat plasma after oral administration of N. officinalis total alkaloids. After addition of an internal standard (verapamil), plasma samples were pretreated first by protein precipitation with methanol and then underwent liquid-liquid extraction with ethyl acetate. Chromatographic separation was achieved using a Waters BEH C18 column (2.1 mm × 100 mm, 1.7 µm) at 30 °C, with gradient elution using a mobile phase consisting of 0.1% formic acid aqueous solution (A) and acetonitrile (B), a flow rate of 0.2 mL/min, and a total run time of 30 min. The detection was performed using an electrospray ionization triple quadrupole tandem mass spectrometer with multiple reaction monitoring and positive ionization mode. RESULTS: Based on the fragmentation patterns of 11 authentic alkaloids and previous reports, 55 alkaloids were identified or tentatively identified in the N. officinalis total alkaloids. Among them, 25 alkaloids were absorbed through the gastrointestinal tract in rats after administration of the N. officinalis total alkaloids. The 11 alkaloids were selected for quantitative analysis. The established quantitative method was fully validated and proved to be sensitive and specific. Satisfactory linearity of the 11 alkaloids obtained in the respective concentration ranges (r > 0.9931). The lower limits of quantification for strictosamide was 20.86 ng/ml, and the other ten alkaloids were all less than 4.47 ng/ml in rat plasma. The intra-and inter-day precision was less than 15% for all 11 alkaloids in terms of relative standard deviation, and the accuracies ranged from -11.4% to 11.1% in terms of relative error. Extraction recovery, matrix effect, and stability were within the required limits in rat plasma. CONCLUSION: The validated method was successfully applied to investigate the pharmacokinetics of the 11 alkaloids in rat plasma after oral administration of N. officinalis total alkaloids. Eleven alkaloids were rapidly absorbed to achieve a maximum plasma concentration with Tmax from 0.25 h to 1.5 h after oral administration. The pharmacokinetic parameters and plasma concentration-time profiles will prove valuable in pre-clinical and clinical investigations on the disposition of N. officinalis total alkaloids.

A review on the bioavailability, bio-efficacies and novel delivery systems for piperine.

As the major naturally occurring alkaloid in pepper with a pungent taste, piperine is known for its beneficial biological functions and therapeutic effects. In this work, the bioavailability and biological activities of piperine were presented and discussed. Novel delivery systems for enhancing the bioavailability of piperine were also reviewed. This study could provide a better understanding of the physiological and biochemical aspects of piperine to be further developed in the food and nutraceutical industries.

Preparation of magnetic yolk-shell structured metal-organic framework material and its application in pharmacokinetics study of alkaloids.

In this study, a magnetic yolk-shell structured metal-organic framework material (Fe3O4@YS-UiO-66-NH2) is prepared by the directional etching of Co2+/peroxymonosulfate and in situ magnetization. The characteristic properties of the material were investigated by using field emission scanning electron microscopy, transmission electron microscopy, energy-dispersive X-ray spectroscopy, X-ray powder diffraction, Fourier transform infrared spectroscopy, vibrating sample magnetometer, Brunauer-Emmett-Teller, and contact angle test. The Fe3O4@YS-UiO-66-NH2 shows the advantages of large surface area, good magnetic property, and satisfactory stability, as well as giving high affinity to alkaloids (ALs) via hydrophilic interaction, hydrogen bonding, and π-π interaction. The results of static adsorption experiment indicate that the Fe3O4@YS-UiO-66-NH2 possesses high adsorption capacity towards ALs and the adsorption behaviors are fitted with Langmuir adsorption isotherm model. Furthermore, a magnetic solid-phase extraction using Fe3O4@YS-UiO-66-NH2 and HPLC method was developed for the analysis of ALs in spiked samples with the recovery of 89.6-100.8%. In addition, the proposed method was successfully applied in the pharmacokinetics study of berberine, coptisine, and palmatine in the rat. In short, the developed method might be used for high-efficient recognition and determination of ALs in plasma sample, which would also provide a new way to fabricate magnetic functionalized metal-organic framework in separation science.

Quercetin and piperine enriched nanostructured lipid carriers (NLCs) to improve apoptosis in oral squamous cellular carcinoma (FaDu cells) with improved biodistribution profile.

Oral squamous cellular carcinoma (OSCC) is considered a life-threatening disease with detection in late stages, which forces us to opt for dangerous treatment with a combination of chemotherapy and radiotherapy. Herbal components such as piperine and quercetin are derived from edible sources, proving their anticancer potential against oral cancer cells in vitro. Encapsulation into lipid matrix-mediated nanostructured lipid carriers (NLCs) can make both drugs bio-accessible. NLCs were synthesised using the high shear homogenisation method and characterised for their physicochemical properties, followed by in vitro cellular evaluation in FaDu oral cancer cells. NLCs showed negatively charged particles smaller than 180 nm with a polydispersity index (PDI) of <0.3. Both drugs were found to encapsulate sufficiently, with >85% entrapment efficiency and an improved drug release profile compared to their pristine counterparts. Differential scanning calorimetry (DSC) thermograms showed conversion into an amorphous matrix in lyophilized NLCs, which was supported by X-ray diffraction (XRD) analysis. The cytotoxicity assay showed the IC50 concentration for dual drug-loaded NLCs, which was more effective than the pure drug solution. NLCs were found to be internalised in cells in a short time with an almost 95% co-localization rate. Dual drug-loaded NLCs showed maximum depolarisation of the mitochondrial membrane along with more apoptotic changes. Improved apoptosis was confirmed in NLCs using flow cytometry. The in vivo biodistribution of Coumarin-6 labelled NLCs in rats confirmed their efficient distribution in various parts of the oral cavity through oral administration. Optimised dual drug-loaded NLCs provide a better option for delivering both drugs through a single lipid matrix against oral cancer.

Metabolic profile and tissue distribution of Humantenirine, an oxindole alkaloid from Gelsemium, after oral administration in rats.

Humantenirine is an active oxindole alkaloid extracted from Gelsemium elegans Benth (G. elegans). In the present study, the metabolites of humantenirine in liver microsomes were first identified by HPLC/QqTOF-MS. Then, the metabolic profile and tissue distribution after oral administration in rats were further investigated. A total of seven metabolites were identified in vitro, and five metabolites in vitro were found in vivo. Moreover, a Ⅱ-phase metabolite was identified first in vivo. The results indicated that humantenirine could be metabolized widely. The parent drug and its metabolites were distributed widely in various tissues and highly in the liver and pancreas. However, the parent drug and its metabolites had low peak intensities in plasma. The elimination of humantenirine occurred rapidly as well, the most unconverted forms of which were found in the kidney. Metabolic pathways, including demethylation, dehydrogenation, oxidation and glucuronidation, were proposed. The present findings may provide a basis for the study of pharmacokinetic characteristics and will contribute to the evaluation of the pharmacology and toxicity of G. elegans.

Pharmacokinetic Characterization and Bioavailability Barrier for the Key Active Components of Botanical Drug Antitumor B (ATB) in Mice for Chemoprevention of Oral Cancer.

This study aims to characterize the pharmacokinetic (PK) profiles and identify important bioavailability barriers and pharmacological pathways of the key active components (KACs) of Antitumor B (ATB), a chemopreventive agent. KACs (matrine, dictamine, fraxinellone, and maackiain) of ATB were confirmed using the antiproliferative assay and COX-2 inhibition activities in oral cancer cells. The observed in vitro activities of KACs were consistent with their cell signaling pathways predicted using the in silico network pharmacology approach. The pharmacokinetics of KACs were determined after i.v., i.p., and p.o. delivery using ATB extract and a mixture of four KACs in mice. Despite good solubilities and permeabilities, poor oral bioavailabilities were estimated for all KACs, mostly because of first-pass metabolism in the liver (for all KACs) and intestines (for matrine and fraxinellone). Multiple-dose PK studies showed 23.2-fold and 8.5-fold accumulation of dictamine and maackiain in the blood, respectively. Moreover, saliva levels of dictamine and matrine were found significantly higher than their blood levels. In conclusion, the systemic bioavailabilities of ATB-KACs were low, but significant levels of dictamine and matrine were found in saliva upon repeated oral administration. Significant salivary concentrations of matrine justified its possible use as a drug-monitoring tool to track patient compliance during chemoprevention trials.

Pharmacokinetics of Synthetic Cathinones Found in Bath Salts in Mouse Brain and Plasma Using High-Pressure Liquid Chromatography-Tandem Mass Spectrometry.

BACKGROUND AND OBJECTIVES: Approximately 10 years ago, "bath salts" became popular as legal alternatives to the psychostimulants cocaine and the amphetamines. These products contained synthetic cathinones, including 3,4-methylenedioxypyrovalerone (MDPV), 4-methylmethcathinone (mephedrone), and 3,4-methylenedioxymethcathinone (methylone). Most preclinical investigations have only assessed the effects of these synthetic cathinones independently; however, case reports and Drug Enforcement Administration (DEA) studies indicate that bath salts contain mixtures of these substances. In this study, we examine the pharmacokinetic interactions of the drug combination. We hypothesized that combined exposure to MDPV, mephedrone, and methylone would result in increased drug concentrations and enhanced total drug concentrations when compared to individual administration. METHODS: Adolescent male Swiss-Webster mice were injected intraperitoneally with either 10 mg/kg MDPV, 10 mg/kg mephedrone, 10 mg/kg methylone, or 10 mg/kg combined MDPV, mephedrone, and methylone. Following injection, brains and plasma were collected at 1, 10, 15, 30, 60, and 120 min. Drugs were extracted via solid-phase extraction, and concentrations were determined using a previously published high-pressure liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method. RESULTS: All drugs crossed the blood-brain barrier quickly. For methylone, the maximal concentration (Cmax) and the total drug exposure [as represented by the area under the concentration-time curve (AUC)] were significantly higher when combined with mephedrone and MDPV in both matrices (2.89-fold increase for both Cmax and AUC with combined treatment). For mephedrone, the Cmax was unchanged, but the AUC in brain was increased when in combination by approximately 34%. Interestingly, for MDPV, the Cmax was unchanged, yet the AUC was higher when MDPV was administered individually (there was a 62% decrease in AUC with combined treatment). CONCLUSIONS: The pharmacokinetics of methylone, mepedrone, and MDPV are altered when the drugs are used in combination. These data provide insight into the consequences of co-exposure to synthetic cathinones in popular bath salt products.

Anti-inflammatory and antioxidant effects of nanoformulations composed of metal-organic frameworks delivering rutin and/or piperine natural agents.

Plant-derived natural medicines have been extensively studied for anti-inflammatory or antioxidant properties, but challenges to their clinical use include low bioavailability, poor solubility in water, and difficult-to-control release kinetics. Nanomedicine may offer innovative solutions that can enhance the therapeutic activity and control release kinetics of these agents, opening the way to translating them into the clinic. Two agents of particular interest are rutin (Ru), a flavonoid, and piperine (Pip), an alkaloid, which exhibit a range of pharmacological activities that include antioxidant and anti-inflammatory effects. In this work, nanoformulations were developed consisting of two metal-organic frameworks (MOFs) with surface modifications, Ti-MOF and Zr-MOF, each of them loaded with Ru and/or Pip. Both MOFs and nanoformulations were characterized and evaluated in vivo for anti-inflammatory and antioxidant effects. Loadings of ∼17 wt.% for a single pro-drug and ∼27 wt.% for dual loading were achieved. The release patterns for Ru and or Pip followed two stages: a zero-order for the first 12-hour stage, and a second stage of stable sustained release. At pH 7.4, the release patterns best fit to zero-order and Korsmeyer-Peppas kinetic models. The nanoformulations had enhanced anti-inflammatory and antioxidant effects than any of their elements singly, and those with Ru or Pip alone showed stronger effects than those with both agents. Results of assays using a paw edema model, leukocyte migration, and plasma antioxidant capacity were in agreement. Our preliminary findings indicate that nanoformulations with these agents exert better anti-inflammatory and antioxidant effects than the agents in their free form.

Blood-to-muscle distribution and urinary excretion of higenamine in rats.

Higenamine is a ß2 -agonist that has been prohibited in sports by the World Anti-Doping Agency. Higenamine could potentially promote anabolism and lipolysis; however, its crucial pharmacokinetics data, particularly muscle distribution, remain unavailable. The present study aims to investigate the blood-to-muscle distribution as well as the urinary excretion of higenamine in laboratory rats. In the first experiment, the microdialysis technique was employed to continuously measure free, protein-unbound concentrations in blood and muscle for 90 min (sampling at a 5-min interval) after rats received IV infusion of higenamine. The mean half-lives of higenamine in blood and muscle were 17.9 and 19.0 min, respectively. The blood-to-muscle distribution ratio (AUCmuscle /AUCblood ) of higenamine was estimated to be 22%. In the second experiment, rats were orally administered with a single-dose higenamine, and their urine samples were profiled at a 12-h interval for up to 48 h. Results showed only a small portion of total consumption (1.44%, ranging 0.71%-2.50%) was excreted in the urine. Among these time points, about 43% cumulative amount of higenamine was eliminated within the first 12 h. Our data suggested that one-quarter of the unbound higenamine rapidly penetrates from the vessels into muscle, distributes to the interstitial fluid, then eliminates from the rat in a short span of time. The muscle tissue is likely to have a low binding affinity for higenamine, and renal excretion plays a minor role in its elimination. Together, our findings provide valuable pharmacokinetics data that may gain deeper insights into higenamine's role in skeletal muscle functions.

Cytisine and cytisine derivatives. More than smoking cessation aids.

Cytisine, a natural bioactive compound that is mainly isolated from plants of the Leguminosae family (especially the seeds of Laburnum anagyroides), has been marketed in central and eastern Europe as an aid in the clinical management of smoking cessation for more than 50 years. Its main targets are neuronal nicotinic acetylcholine receptors (nAChRs), and pre-clinical studies have shown that its interactions with various nAChR subtypes located in different areas of the central and peripheral nervous systems are neuroprotective, have a wide range of biological effects on nicotine and alcohol addiction, regulate mood, food intake and motor activity, and influence the autonomic and cardiovascular systems. Its relatively rigid conformation makes it an attractive template for research of new derivatives. Recent studies of structurally modified cytisine have led to the development of new compounds and for some of them the biological activities are mediated by still unidentified targets other than nAChRs, whose mechanisms of action are still being investigated. The aim of this review is to describe and discuss: 1) the most recent pre-clinical results obtained with cytisine in the fields of neurological and non-neurological diseases; 2) the effects and possible mechanisms of action of the most recent cytisine derivatives; and 3) the main areas warranting further research.