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

To prepare composite phospholipid liposomes containing total alkaloids of Strychnos nux-vomica with hydrogenated soybean phosphatidylcholine (HSPC) and 1, 2-dipalmitoyl-sn-glycero-3-phosphacholine (DPPC), and compare with normal DPPC thermosensitive liposomes for thermosensitive release property. Total alkaloids were extracted from S. nux-vomica with the impregnation method and further purified. Liposomes containing total alkaloids, thermosensitive liposomes and conventional thermosensitive liposomes without thermosensitive release property were prepared by ammonium sulfate transmembrane gradients and stealth liposome technique. Their encapsulation efficiency (EE), grain size, zeta potential and drug release behavior were compared. Their EEs and zeta potentials were almost identical; but the grain sizes of composite phospholipid liposomes and thermosensitive liposomes were significantly smaller than conventional liposomes. After comparing release behaviors of the three liposomes at 37, 43 degrees C, we found that the release of composite phospholipid liposomes was significantly lower than that of thermosensitive liposomes at 37 degrees C, but higher than that of thermosensitive liposomes at 43 degrees C. Meanwhile, conventional liposomes, with a very high phase-transition temperature, showed only slight release behavior at both temperatures. The study results showed that composite phospholipid liposomes had a better thermosensitive release behavior when the dosage of lysophosphatidic was reduced by 2. 5 times.
Alkaloids ; chemistry ; Liposomes ; chemistry ; Phospholipids ; chemistry ; Strychnos nux-vomica ; chemistry

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 observe the therapeutic effect and mechanism of nux vomica total alkali gel (NVTAG) on adjuvants arthritis (AA) rats.

METHODSD rats were randomly divided into nine groups: the normal group, the AA model group, NVTAG high, middle and low-dose (25, 12.5, 6.25 mg x kg(-1)) groups and the Votalin control (diclofenac diethylamine emulgel, 50 mg x kg(-1)) group. Except for the normal group, the remaining groups were transcutaneously administered with 0.1 mL freund's adjuvant complete (FCA) for inflammation in left rear feet and then evenly treated with medicine and packed with oilpapers. The foot volume method was adopted to determine foot swelling degree, with pain scoring and polyarthritis scoring. HE staining was used to observe arthro-pathologic injury. The content of prostaglandin E2 (PGE2), interleukin-1 (IL-1), IL-6, tumor necrosis factor (TNF-alpha) and vascular epidermal growth factor (VEGF) in synovium homogenates were measured by enzyme-linked immuno-absorbent assay (ELISA) respectively.

RESULTCompared with the model group, NVTAG and control gel can obviously reduce the foot swelling degree, polyarthritis indicators and relieve arthro-pathologic injury in AA rats (17-21 d). The levels of IL-1, PGE2, IL-6, VEGF and TNF-alpha in synovial homogenates of AA rats were also reduced by NVTAG significantly.

CONCLUSIONNVTAG shows an antergic effect on AA progress in rats, which is closely related to inhibition of development of inflammatory mediator.

Alkalies ; Animals ; Arthritis, Experimental ; drug therapy ; immunology ; pathology ; Cytokines ; analysis ; Gels ; Male ; Phytotherapy ; Rats ; Rats, Wistar ; Strychnos nux-vomica

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

OBJECTIVETo prepare a noisome formulation of Semen Strychni alkaloids extract with high encapsulation efficiency.

METHODS. Strychni alkaloids were encapsulated into niosomes by pH gradient loading method. The factors influencing on the encapsulation efficiency were investigated, and formulation and preparation process of niosomes were optimised and validated.

RESULTWhen the drug to lipid weight ratio was under 1: 10, pH gradient in buffer solution of citric acid at 50 degrees C was more than 4.0, the niosomes (mean diameter 179.2 nm and Zeta potential -25.41 mV) were formed with encapsulation efficiency of over 86.9%.

CONCLUSIONThe pH gradient loading method was reliable for preparing niosomes of Semen Strychni alkaloids extract.

Alkaloids ; chemistry ; Capsules ; Drug Compounding ; methods ; Drugs, Chinese Herbal ; chemistry ; Hydrogen-Ion Concentration ; Liposomes ; chemistry ; Strychnos nux-vomica ; chemistry ; Temperature

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 determine the plasma protein binding rates of brucine and strychnine in total alkaloids from the seed of Strychnou nux-vomica, and make comparison with the single components at the same concentration.

METHODUltrafiltration was employed to determine the rat the plasma protein binding rate of the alkaloids from the seed of S. nux-vomica. The plasma concentrations were measured by RP-HPLC.

RESULTThe protein binding rates of brucine were (65.60 3.01)%, (68.20 +/- 7.80)%, (59.58 +/- 3.78)% when the plasma concentrations was 0.520, 1.300, 2.600 mg x L(-1), respectively. The protein binding rates of strychnine was (66.17 +/- 6.36)%, (67.10 +/- 2.52)%, (57.21 +/- 0.79)% when the plasma concentrations were 0.936, 2.340, 4.680 mg x L(-1) respectively. As to the total alkaloids from the seed of S. nux-vomica, The protein binding rate of brucine was (62.19 +/- 2.45)%, (69.55 +/- 5.84)%, (61.76 +/- 3.68)% when the plasma concentrations were 0.519, 1.288, 2.607 mg x L(-1), respectively. And the protein binding rates of strychnine were (54.79 +/- 3.55)%, (57.13 +/- 4.49)%, (59.31 +/- 3.65)% when the plasma concentrations were 0.940, 2.338, 4.674 mg x L(-1), respectively.

CONCLUSIONBrucine and strychnine have medium capacity in binding to plasma protein. In comparison with the single component of the same concentration, the protein binding rate of brucine in total alkaloids shows little difference, while there seems to be an obvious decrease for strychnine.

Alkaloids ; analysis ; pharmacokinetics ; Animals ; Blood Proteins ; chemistry ; metabolism ; Drugs, Chinese Herbal ; analysis ; pharmacokinetics ; Protein Binding ; Rats ; Rats, Sprague-Dawley ; Seeds ; chemistry ; Strychnos ; 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