AIM: The application of strychnine (S) is limited due to its toxicity; strychnine N-oxide (SNO) is a derivative of strychnine. The aim was to employ zebrafish embryos to investigate and compare the developmental toxicity induced by S and SNO. METHODS: The toxicity of S and SNO was examined through the hatching rate and survival rate. Morphological changes of the zebrafish were observed with a dissecting microscope. Apoptosis was detected through acridine orange (AO) staining and flow cytometry. Apoptotic genes were measured by RT-PCR. RESULTS: Embryo malformation was observed in the embryos exposed to S at 200 μmol·L(-1). When SNO concentration was increased to 1 mmol·L(-1), scoliolosis, and pericardial edema could be seen in some embryos. Results from fluorescence microscopy and flow cytometry analysis showed that S at 200 μmol·L(-1) induced apoptosis, whereas the apoptotic rate in the SNO-treated group (200 μmol·L(-1)) was much lower than that in the S group. RT-PCR analysis showed that p53 mRNA expression and the ratio of Bax/Bcl-2 in the S group were significantly altered compared with the control group (*P < 0.05). Moreover, Bax mRNA expression in both S and SNO group were significantly different from that in the control group (**P < 0.01). CONCLUSION These results lead to the conclusion that SNO has significantly lower toxicity than S in zebrafish embryos.
Animals ; Apoptosis ; drug effects ; Cyclic N-Oxides ; toxicity ; Drugs, Chinese Herbal ; toxicity ; Female ; Male ; Oxidative Stress ; drug effects ; Proto-Oncogene Proteins c-bcl-2 ; Strychnine ; analogs & derivatives ; toxicity ; Strychnos ; adverse effects ; chemistry ; Tumor Suppressor Protein p53 ; genetics ; metabolism ; Zebrafish ; embryology ; genetics ; metabolism ; Zebrafish Proteins ; genetics ; metabolism

OBJECTIVEA sensitive liquid chromatography-tandem mass spectrometric (LC-MS/MS) method has been developed and validated for the determination of brucine and strychnine in rat plasma.

METHODSamples were extracted by ethyl acetate-n-butanol (7: 3). Chromatographic separation was operated on ZORBAX XDB-C18 column with gradient elution of acetonitrile-methanol-water (0.05% acetic acid and 10 nmol x L(-1) ammonium formate contained), followed by LC-MS/MS in positive electrospray ionization. Quantification was carried out on multiple reaction monitoring (MRM) of the transition m/z 395.2/324.2, m/z 335.2/184.2 and m/z 199.1/171.1 for brucine, strychnine and tacrine (internal standard), respectively.

RESULTThe method was linear in the range of 0.195-100 and 0.07840 microg x L(-1) for brucine and strychnine, with coefficient correlation 0.994 and 0.996 respectively. The recoveries of extraction were 78.9% - 102.4% for brucine and 95.2% - 106.1% for strychnine. Precision, accuracy, stability and matrix effect of the analytes met the requirement. The method was applied to a pharmacokinetic study of brucine and strychnine after cutaneous administration of Semen Strychni niosome gel. The C(max) were (26.20 +/- 5.81) and (12.50 +/- 3.00) microg x L(-1) while the AUC(0-infinity), were (193.75 +/- 39.43) and (98.25 +/- 28.54) microg x h x L(-1) of the two components.

CONCLUSIONWe conclude that the niosomes may reduce the systemic exposures and prolong the local release of brucine and strychnine.

Administration, Cutaneous ; Analgesics ; analysis ; pharmacokinetics ; Animals ; Chromatography, Liquid ; Convulsants ; analysis ; pharmacokinetics ; Female ; Gels ; chemistry ; Liposomes ; chemistry ; Male ; Plants, Medicinal ; chemistry ; Rats ; Rats, Sprague-Dawley ; Seeds ; chemistry ; Semen ; chemistry ; Specific Pathogen-Free Organisms ; Strychnine ; analogs & derivatives ; analysis ; pharmacokinetics ; Strychnos nux-vomica ; chemistry ; Tandem Mass Spectrometry

OBJECTIVETo study different in vivo pharmacokinetic regularity of brucine, total alkaloids of scorched sand-prepared Strychni Semen products and Strychni Semen pulveratum in rats, and probe into mutual impact between single component and compound.

METHODRats in each group were orally administered with brucine, total alkaloids of scorched sand-prepared Strychni Semen products and Strychni Semen pulveratum suspension. The in vivo plasma concentrations of brucine in rats were determined by HPLC. A compartment model was made for the blood drug concentration-time curve using 3P97 software package and the pharmacokinetic parameters of each group were calculated and compared.

RESULTThe in vivo metabolic process of brucine in rats complied with the two-compartment model, weight W = 1/C2. The results of variance analysis showed that among three existing forms of brucine with same dosage, the brucine solution group and the total alkaloids group of scorched sand-prepared Strychni Semen products showed significant differences in C(max), MRT (P < 0.05); and the brucine solution group and the Strychni Semen pulveratum suspension group showed significant differences in C(max), AUC(0-t), and AUC(0-infinity), in which the latter displayed minimum C(max), AUC(0-t) and AUC(0-infinity).

CONCLUSIONThe total alkaloids group of scorched sand-prepared Strychni Semen products showed a relatively longer retention time of effective components of brucine in plasma, while the Strychni Semen pulveratum suspension group showed a lower bioavailability.

Animals ; Male ; Medicine, Chinese Traditional ; Plants, Medicinal ; chemistry ; Rats ; Rats, Sprague-Dawley ; Strychnine ; analogs & derivatives ; pharmacokinetics

The aim of this study was to develop a sustained release converse thermosensitive hydrogel for intra-articular injection using chitosan-glycerol-borax as matrix, its physical properties and biocompatibility were investigated. Taking gelation time and gelation condition as index, the influence of concentration of chitosan, ratio of chitosan to glycerol, pH on physical properties of hydrogel were investigated. And then the in vitro drug release, rheological properties and biocompatibility were studied. The thermosensitive hydrogel flows easily at room temperature and turns to gelation at body temperature, which can certainly prolong the release of drug and has good biocompatibility.
Analgesics ; administration & dosage ; adverse effects ; chemistry ; Animals ; Chitosan ; administration & dosage ; chemistry ; Delayed-Action Preparations ; Drug Compounding ; Hydrogels ; administration & dosage ; chemistry ; Hydrogen-Ion Concentration ; Inflammation ; chemically induced ; Injections, Intra-Articular ; Knee Joint ; drug effects ; Male ; Materials Testing ; Plants, Medicinal ; chemistry ; Rats ; Rats, Sprague-Dawley ; Rheology ; Seeds ; chemistry ; Strychnine ; administration & dosage ; adverse effects ; analogs & derivatives ; chemistry ; Strychnos nux-vomica ; chemistry ; Surface Properties ; Synaptic Membranes ; drug effects ; Temperature

OBJECTIVE: To establish a method for determination of strychnine and brucine in formaldehyde fixed tissue by LC-MS/MS analysis. METHODS: The samples were pretreated with solid phase extraction using SCX cartridges and separated on SB-C18 column with mobile phase 0.1% formic acid : 0.1% formic acid-acetonitrile (75:25). Electrospray ionization (ESI) source was utilized and operated in positive ion mode. Multiple reactions monitoring (MRM) mode was applied. External standard method was applied for quantitation. RESULTS: The chromatographic separation of strychnine and brucine in formaldehyde fixed nephritic and hepatic tissues resulted successfully. The standard curve was linear in the range of 0.002-2.0 microg/g for strychnine and brucine in formaldehyde fixed tissues, and the correlation coefficient was more than 0.996. The limits of detection (LOD) of strychnine and brucine in nephritic tissues were 0.06ng/g and 0.03 ng/g, respectively. The LOD of both chemicals were 0.3 ng/g in hepatic tissues. The extraction recovery rate was more than 74.5%. The precision of intra-day and inter-day were both less than 8.2%. CONCLUSION Strychnine and brucine can be sensitive to be determined in formaldehyde fixed tissue by LC-MS/MS analysis. It can be applied in the forensic toxicological analysis.
Chromatography, Liquid/methods* ; Forensic Toxicology ; Formaldehyde/chemistry* ; Formates ; Kidney/metabolism* ; Limit of Detection ; Liver/metabolism* ; Mass Spectrometry ; Molecular Structure ; Reproducibility of Results ; Spectrometry, Mass, Electrospray Ionization/methods* ; Strychnine/chemistry* ; Tandem Mass Spectrometry ; Tissue Distribution

Abstract: The activities of four CYP450 enzymes (CYP3A, 1A2, 2El and 2C) and the mRNA expression levels of CYP1A2, 2El, 2Cll and 3A1 in rat liver were determined after Wistar rats were orally administered with brucine (BR) at three dosage levels (3, 15 and 60 mg.kg-1 per day) and the high dose of BR combined with glycyrrhetinic acid (GA, 25 mg.kg-1 per day) or liquiritin (LQ, 20 mg.kg-1 per day) for 7 consecutive days. Compared with the control, brucine caused 24.5% and 34.6% decrease of CYP3A-associated testosterone 6beta-hydroxylation (6betaTesto-OH) and CYP2C-associated tolbutamide hydroxylation (Tol-OH), respectively, and 146.1% increase of CYP2El-associated para-nitrophenol hydroxylation (PNP-OH) at the high dose level. On the other hand, (BR+GA) caused 51.4% and 33.5% decrease, respectively, of CYP2El-associated PNP-OH and CYP1A2-associated ethoxyresorufin-O-de-ethylation (EROD) as compared with the high dose of BR group. Meanwhile, (BR+LQ) caused 41.1% decrease of CYP2El-associated PNP-OH and 37.7% increase of CYP2C-associated Tol-OH. The results indicated that the co-administration of BR with GA or LQ had effect on mRNA expression and activities of the CYP450 enzymes mentioned above to some extent, and the in vivo antagonism of LQ on BR-induced CYPs adverse effects and the in vivo inhibitory action of GA on CYP2E1 and 1A2 might play an important role in the detoxification of Radix Glycyrrhizae against Strychnos nux-vomica L.
Animals ; Aryl Hydrocarbon Hydroxylases ; genetics ; metabolism ; Cytochrome P-450 CYP1A1 ; metabolism ; Cytochrome P-450 CYP1A2 ; genetics ; metabolism ; Cytochrome P-450 CYP2E1 ; genetics ; metabolism ; Cytochrome P-450 CYP3A ; genetics ; metabolism ; Cytochrome P-450 Enzyme System ; genetics ; metabolism ; Cytochrome P450 Family 2 ; Flavanones ; pharmacology ; Gene Expression Regulation, Enzymologic ; Glucosides ; pharmacology ; Glycyrrhetinic Acid ; pharmacology ; Hydroxylation ; Liver ; enzymology ; metabolism ; Male ; Nitrophenols ; metabolism ; Plants, Medicinal ; chemistry ; RNA, Messenger ; metabolism ; Rats ; Rats, Wistar ; Steroid 16-alpha-Hydroxylase ; genetics ; metabolism ; Steroid Hydroxylases ; metabolism ; Strychnine ; analogs & derivatives ; isolation & purification ; pharmacology ; Strychnos nux-vomica ; chemistry ; Tolbutamide ; metabolism

OBJECTIVETo compare the pharmaceutical properties and the anti-tumor activities of three kinds of stealth liposomes prepared with different phospholipid composition containing brucine.

METHODStealth liposomes with different phospholipids composition, such as soybean phosphatidycholine (SPC), hydrogenated soybean phosphatidylcholine (HSPC) and the complex of SPC and HSPC, were prepared by ammonium sulfate transmembrane gradient method. Pharmaceutical properties such as shape, encapsulation efficiency and size of three stealth liposomes were compared intensively. Anti-tumor activity of SPC, HSPC and novel stealth liposomes composed of both SPC and HSPC were compared by established mouse liver cancer H22 model. Meanwhile, the mice body weight and immune organ weight were also compared.

RESULTThe encapsulation efficiency of novel, SPC and HSPC stealth liposomes were 77.7%, 64.8% and 74.8%, respectively. The mean diameters of them were less than 100 nm. The tumor inhibition rate of novel, HSPC and SPC stealth liposomes were 57.88%, 49.15%, 23.37%, respectively. The mice body weight, thymus gland index of three stealth liposomes group and spleen index of novel stealth liposomes group had no significant difference with the negative group while SPC and HSPC stealth liposomes group increased the spleen index.

CONCLUSIONPhospholipids composition is the key factor which determines the antitumor activity of brucine-loaded stealth liposomes.

Animals ; Antineoplastic Agents ; chemistry ; pharmacology ; Body Weight ; drug effects ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Humans ; Liposomes ; adverse effects ; chemistry ; Mice ; Particle Size ; Phospholipids ; chemistry ; Strychnine ; analogs & derivatives ; chemistry

OBJECTIVETo compare the pharmacokinetic characteristics of brucine following intravenous administration of liposomes, containing total alkaloids from seed of Strychnos nux-vomica, to rats with different phospholipids composition.

METHODLiposomes containing the total alkaloids were prepared by the method of ammonium sulfate transmembrane gradients and stealth liposome technique. The contents of total alkaloids and brucine in liposomes were determined and compared after free drug being removed. After intravenous administration of total alkaloids solution or liposomes with different composition, plasma samples were drawn at predetermined time points and the concentrations of brucine were determined by a validated method of HPLC. Pharmacokinetic analysis was performed by 3P97 program.

RESULTThe ratios of brucine to total alkaloids in liposomes hardly varied with phospholipids composition. Compared with SPC liposome, AUC of brucine was increased 13.3-fold and apparent volume of distribution was decreased to only 3.6% following intravenous administration of HSPC liposome. In addition, besides that AUC of brucine was slightly increased, most pharmacokinetic parameters were not significantly changed after administration of the novel liposome compared with those of SPC liposome.

CONCLUSIONPhospholipids composition has a significant influence on the pharmacokinetics of brucine after intravenous administration of liposomes containing total alkaloids from seed of S. nux-vomica.

Alkaloids ; administration & dosage ; pharmacokinetics ; Animals ; Drugs, Chinese Herbal ; administration & dosage ; pharmacokinetics ; Infusions, Intravenous ; Liposomes ; administration & dosage ; pharmacokinetics ; Male ; Models, Animal ; Rats ; Rats, Sprague-Dawley ; Seeds ; chemistry ; Strychnine ; administration & dosage ; analogs & derivatives ; pharmacokinetics ; Strychnos nux-vomica ; chemistry

To study the effect of liquiritin (Liq) on the transport of strychnine (Str) in Caco-2 cell monolayer model, the transport parameters of Str, such as apparent permeability coefficient (P app (B-->A) and P app (A-->B)) and cumulative transport amount (TRcum), were determined and comparatively analyzed when Str was used solely and co-used with Liq. The effect of drug concentrations, conveying times, P-glycoprotein (P-gp) inhibitor verapamil and conveying liquor pH values on the transport of Str were also investigated. The results indicated that the absorption of Str in Caco-2 cell monolayer model was well and the passive transference was the main intestinal absorption mechanism of Str in the Caco-2 monolayer model, along with the excretion action mediated by P-gp. Liq enhanced the absorption of Str. Meanwhile, conveying liquor pH value had significant influence on the excretion transport of Str.
ATP-Binding Cassette, Sub-Family B, Member 1 ; antagonists & inhibitors ; Absorption ; drug effects ; Biological Transport ; drug effects ; Caco-2 Cells ; Flavanones ; isolation & purification ; pharmacology ; Glucosides ; isolation & purification ; pharmacology ; Glycyrrhiza uralensis ; chemistry ; Humans ; Hydrogen-Ion Concentration ; Permeability ; Plants, Medicinal ; chemistry ; Strychnine ; isolation & purification ; pharmacokinetics ; Strychnos nux-vomica ; chemistry ; Verapamil ; pharmacology

OBJECTIVETo prepare and evaluate brucine-loaded polylacticacid nanoparticles (Bru-PLA-NPs).

METHODThe Bru-PLA-NPs were prepared by solvent diffusion method. The physical, chemical properties and in vitro release behavior of the prepared Bru-PLA-NPs were evaluated, respectively.

RESULTThe mean particle size of the prepared Bru-PLA-NPs was 95 nm with polydispersity index of 0.362. The zeta potential was -15.68 mV. The mean loading and entrapment efficiency of Bru were 7% and 37%, respectively. Compared with Bru solution, an obvious sustained release behavior of Bru from Bru-PLA-NPs was observed in the in vitro release experiment.

CONCLUSIONThe Bru-PLA-NPs prepared by solvent diffusion method exhibit small particle size, high Bru-loading efficiency, and obvious sustained release in vitro

Drug Carriers ; chemistry ; Drug Delivery Systems ; methods ; Drugs, Chinese Herbal ; chemistry ; Kinetics ; Lactic Acid ; chemistry ; Nanoparticles ; chemistry ; Particle Size ; Polyesters ; Polymers ; chemistry ; Strychnine ; analogs & derivatives ; chemistry