Nuciferine analogs block voltage-gated sodium, calcium and potassium channels to regulate the action potential and treat arrhythmia.

Dysfunction of the Nav1.5, Cav1.2, and Kv channels could interfere with the AP and result in arrhythmias and even heart failure. We herein present a novel library of nuciferine analogs that target ion channels for the treatment of arrhythmias. Patch clamp measurements of ventricular myocytes revealed that 6a dramatically blocked both the INa and ICa without altering the currentvoltage relationship (including the activation potential and peak potential), accelerated the inactivation of Nav and Cav channels and delayed the resurrection of these channels after inactivation. Additionally, 6a significantly decreased the APA and RMP without affecting the APD30 or APD50. The IC50 values of 6a against Nav1.5 and Cav1.2 were 4.98 µM and 4.62 µM, respectively. Furthermore, 6a (10 µM) blocked IKs, IK1, and Ito with values of 17.01 %±2.54 %, 9.09 %±2.78 %, and 11.15 %±3.52 %, respectively. Surprisingly, 6a weakly inhibited hERG channels, suggesting a low risk of proarrhythmia. The cytotoxicity evaluation of 6a with the H9c2 cell line indicated that this compound was noncytotoxic. In vivo studies suggested that these novel nuciferine analogs could shorten the time of arrhythmia continuum induced by BaCl2 and normalize the HR, QRS, QT and QTc interval and the R wave amplitude. Moreover, 6a dose-dependently affected aconitine-induced arrhythmias and notably improved the cumulative dosage of aconitine required to evoke VP, VT, VF and CA in rats with aconitine-induced arrhythmia. In conclusion, nuciferine analogs could be promising ion channel blockers that could be further developed into antiarrhythmic agents.

[Preparation of Cangai oil transfersomes patches and its in vitro evaluation].

L_9(3~4) orthogonal experiment design was used to optimize the preparation of the patches,and investigate its affecting factors and skin irritation. Eugenol was taken as the index component to study the release behavior in vitro and percutaneous penetration of Cangai oil transfersomes patches by HPLC.The results showed that the optimal prescription for preparing Cangai oil transfersomes patches were Eudragit E100 0.6 g, succinic acid 0.08 g,triethyl citrate 0.25 g,glycerol 0.2 g.Patches prepared by the preferred preparation had a flat appearance without obvious bubbles.The initial adhesion was 18.33±2.52, the stickiness was(30.01±2.45) min,and the peel strength was(5.62±0.95) kN·m~(-1).The results of affecting factors experiment showed the order of factors affecting its adhesion was humidity>temperature>lighting,and the skin irritation test results showed no significant skin irritation after 24 h of single administration. The results of drug release behavior in vitro showed that the release and the percutaneous penetration of both Cangai oil patches and Cangai oil transfersomes patches conformed to the Higuchi equation.The release amount of eugenol were 80.66% and 82.25% at 72 h, with no significant difference. The cumulative permeation area of eugenol per unit area reached(0.195 6±0.065 9),(0.131 0±0.045 5) mg·cm~(-2) at 72 h, with significant differences(P<0.05).The experiment results proved that the preparation process of Cangai oil transfersomes patches was stable,and the prepared patches had a good adhesion. At the same time,the preparation of transfersomes patches could alleviate and control the release of the drug to a certain extent, and provide a certain experimental basis for clinical pediatric drug safety.

[Determination of 5 nucleosides components in culture of Paecilomyces hepialid by HPLC].

The concentration of 5 nucleosides, uracil, uridine, guanidine, adenine and adenosine in culture of Paecilomyces hepialid was determined by the developed method of HPLC. The HPLC method was performed on a Waters SunFire C18 (4.6 mm x 250 mm, 5 µm) column with methanol-water gradient elution as the mobile phase. The detection wavelength was 260 nm and the colunmn temperature was controlled at 30 °C. The linear range was 10.00-200.00 mg · L(-1) (r = 0.9994) for uracil, 10.10-202.00 mg · L(-1) (r = 0.9992) for uridine, 10.00-200.00 mg · L(-1) (r = 0.9991) for guanidine, 10.30-206.00 mg · L(-1) (r = 0.9992) for adenine and 10.45-209.00 mg · L(-1) (r = 0.9991) for adenosine, respectively. The RSD of precision was 0.032%, 0.035%, 0.039%, 0.049%, 0.00080%, respectively. The average recoveries of uracil, guanidine, adenine, and adenosine were 97.34%, 99.10%, 101.6%, 98.61% and 100.2% with RSD of 1.3%, 2.1%, 0.96%, 0.95%, and 1.3% respectively. The method showed high sensitivity, good selectivity, linearity and repeatability, which was suitable for the content analysis of 5 nucleosides components in P. hepialid and its extracts.

Crebanine inhibits voltage-dependent Na+ current in guinea-pig ventricular myocytes / 中国天然药物

AIM@#To study the effects of crebanine on voltage-gated Na(+) channels in cardiac tissues.@*METHODS@#Single ventricular myocytes were enzymatically dissociated from adult guinea-pig heart. Voltage-dependent Na(+) current was recorded using the whole cell voltage-clamp technique.@*RESULTS@#Crebanine reversibly inhibited Na(+) current with an IC50 value of 0.283 mmol·L(-1) (95% confidence range: 0.248-0.318 mmol·L(-1)). Crebanine at 0.262 mmol·L(-1) caused a negative shift (about 12 mV) in the voltage-dependence of steady-state inactivation of Na(+) current, and retarded its recovery from inactivation, but did not affect its activation curve.@*CONCLUSION@#In addition to blocking other voltage-gated ion channels, crebanine blocked Na(+) channels in guinea-pig ventricular myocytes. Crebanine acted as an inactivation stabilizer of Na(+) channels in cardiac tissues.

[Akaloids from roots of Stephania dentifolia].

Eight alkaloids were isolated from the thin sulfuric acid extracts of the fresh roots of Stephania dentifolia by aluminum oxide, silica and Sephadex LH-20 column chromatography methods. Based on the spectroscopic analysis and chemical evidence, the structures of these alkaloids were identified as sinoacutine (1), sinomenine (2), cephamonine (3), tetrahydropalmatine (4), capaurine (5), stepharanine (6), (+)-stepharine (7) and palmatine (8). All compounds were obtained from this plant for the first time.

[Enhancing effect of volatile oils of rhizoma zingiberis, flos magnoliae and fructus litseae on permeation of rotundine in vitro].

OBJECTIVE: To investigate the enhancing effect of volatile oils of Rhizoma Zingiberis (RZ), Flos Magnoliae (FM), Fructus Litseae (FL), Azone and pairwise combinations on the permeation of Rotundine in vitro. METHODS: To screen out the volatile oils with the best percutaneous enhancing effect on Rotundine, a test of penetration through rats skin was conducted by using an improved Franz diffusion cell. The accumulative penetration amount of Rotundine was determined by UV and HPLC. RESULTS: All of the 3 volatile oils had enhancing effect on Rotundine permeation. The average accumulative doses of Rotundine for 8 hours (Q8, mg/cm2) of 5% volatile oil of FL, 5% volatile oil of, RZ, 2.5% FL + 2.5% Azone were 6.0758, 6.1148, 6.5487, the enhancement ratios of 4 hours were 1.01, 1.00, 1.13 respectively. CONCLUSION: 2.5% FL + 2.5% Azone had the best effect of percutaneous enhancing on Rotundine.

[Effects of volatile oil of Rhizoma zingiberis and other two kinds of volatile oil on percutaneous penetration of bullatine A via hairless mouse skin in vitro].

OBJECTIVE: To investigate the effects of volatile oils of Rhizoma Acori Tatarinowii (RAT), Semen Myristicae (SM) and Pericarpium Citri Reticulatae (PCR) on percutaneous penetration of bullatine A via hairless mouse skin in vitro. METHOD: By an improved Franz diffusion, the effects of three kinds of volatile oils on the percutaneous penetration of bullatine A were observed and compared with Azone, and the cumulative amount of bullatine A was determined by HPLC. RESULT: The penetration enhancement ratios of bullatine A with 7% volatile oil RAT and SM, 5% volatile oil of PCR and 3% Azone were 6.52, 6.74, 2.18, 6.03, respectively. CONCLUSION: The volatile oil of RAT, SM and PCR enhance permeation of bullatine A, effectively.

A study of genetic structure of Stephania yunnanensis (Menispermaceae) by DALP.

Genetic diversity and genetic structure within and among ten populations of Stephania yunnanensis H. S. Lo and three populations of S. epigaea H. S. Lo from Yunnan province were evaluated by direct amplification of length polymorphism (DALP) markers. Five primer groups were screened, and a total of 287 DNA fragments were amplified, among which 266 were polymorphic, averaging 53.2 polymorphic bands per primer group in S. yunnanensis. The percentage of polymorphic bands of S. yunnanensis was 92.68% at the species level and 61.92% within the ten populations sampled. At the species level, the observed number of alleles (N (a)) was 1.9268 and the effective number of alleles (N (e)) was 1.5933; Nei's gene diversity (H) was 0.3414; Shannon's information index (I) was 0.5057. At the population level, N (a) = 1.6192, N (e) = 1.4001, H = 0.2298, and I = 0.3401. Total gene diversity of S. yunnanensis was 0.3419. Gene diversity within population was 0.2298, coefficient of gene differentiation was 0.3278, and estimated gene flow was 1.0254. The results indicated that the genetic differentiation was relatively higher among populations of S. yunnanensis. DALP markers were an informative and useful method for assaying genetic diversity and authenticating species of Stephania. These data could provide basic molecular evidence for establishing a reasonable strategy for protecting and exploiting the resource of S. yunnanensis.

[Study on pharmacokinetics of crebanine injection in rabbits].

OBJECTIVE: To develop an HPLC method for the determination of serum level of Crebanine (Cre) and study on the pharmacokinetics of Cre injection in rabbits. METHOD: To sample blood serum from the rabbits' ears which were injected the Cre by 2.0 mg x kg(-1) at different time and use HPLC to determine the concentration of Cre in it, the pharmacokinetic parameters were accessed by the DAS software. RESULT: Cre was fitted to a two compartment open pharmacokinetic model in rabbits. There was no signifiant difference between the male and female rabbits'pharmacokinetic by t-test. The mainly pharmacokinetic parameters were: t1/2alpha = (3. 246 +/-0.222) min, t1/2beta = (36.67+/-5.52) min, Cmax = (1.401 +/- 0.062) mg x L(-1), Vd = (5.928 +/- 0.877) L x kg(-1), Cl = (0. 051 +/-0.003) L x min(-1) x kg(-1). CONCLUSION: This experiment can objectively show the pharmacokinetics regularity of Crebanine injection in rabbits. Crebanine injection was a speeding disposition drug (t1/2 <1 h) and disposed extensively and rapidly in rabbits.