Pharmacokinetics, bioavailability and metabolism of neferine in rat by LC-MS/MS and LC-HRMS.

In this study, a simple and sensitive analytical method based on liquid chromatography-tandem mass spectrometry (LC-MS/MS) was developed and validated for the determination of neferine in rat plasma. After acetonitrile-mediated protein precipitation, the samples were separated on an Acquity BEH C18 column (2.1 × 50 mm, 1.7 µm) maintained at 40°C. The mobile phase comprising 0.1% formic acid in water and acetonitrile was delivered at a flow rate of 0.4 ml/min. The mass detection was conducted using multiple reaction monitoring mode with ion transitions at 625.4 > 206.3 and m/z 622.9 > 380.9 for neferine and internal standard, respectively. The assay was demonstrated to be linear over the concentration range of 0.5-1,000 ng/ml, with correlation coefficient >0.999 (r > 0.999). The validated method was further applied to the pharmacokinetic study of neferine in rat plasma. In addition, the metabolism of neferine was investigated using high-resolution mass spectrometry. A total of six metabolites from rat liver microsomes and plasma were detected and their structures were identified according to their fragment ions. The proposed metabolic pathways of neferine were demethylation, dealkylation, dehydrogenation and glucuronidation.

Inhalation of Tetrandrine-hydroxypropyl-ß-cyclodextrin Inclusion Complexes for Pulmonary Fibrosis Treatment.

Pulmonary fibrosis (PF) is a kind of interstitial lung disease with the features of progressive and often fatal dyspnea. Tetrandrine (TET) is the major active constituent of Chinese herbal Stephania tetrandra S. Moore, which has already applied clinically to treat rheumatism, lung cancer, and silicosis. In this work, a tetrandrine-hydroxypropyl-ß-cyclodextrin inclusion compound (TET-HP-ß-CD) was developed for the treatment of pulmonary fibrosis via inhalation administration. TET-HP-ß-CD was prepared by the freeze-drying method and identified using the cascade impactor, differential scanning calorimetry (DSC), X-ray diffraction (XRD), and Fourier transform infrared spectrum (FT-IR). A bleomycin-induced pulmonary fibrosis rat model was used to assess the effects of inhaled TET and TET-HP-ß-CD. Animal survival, hydroxyproline content in the lungs, and lung histology were detected. The results showed that inhalation of TET-HP-ß-CD alleviated inflammation and fibrosis, limited the accumulation of hydroxyproline in the lungs, regulated protein expression in PF development, and improved postoperative survival. Moreover, nebulized delivery of TET-HP-ß-CD accumulated chiefly in the lungs and limited systemic distribution compared with intravenous administration. The present results indicated that inhalation of TET-HP-ß-CD is an attractive candidate for the treatment of pulmonary fibrosis.

Pharmacokinetics of 10-hydroxycamptothecin-tetrandrine liposome complexes in rat by a simple and sensitive ultra-high performance liquid chromatography with tandem mass spectrometry.

10-Hydroxycamptothecin is a drug to cure various cancers. However, the 10-hydroxycamptothecin cannot be widely applied in clinics due to fast elimination and resistance of various cancers to the drug. Nevertheless, co-treatment with tetrandine is known to reverse the resistance of multi-drug resistant cancers, and may present an effective strategy to improve the efficacy of 10-hydroxycamptothecin. In order to improve the bioavailability and prolong the treatment time of the 10-hydroxycamptothecin in vivo, we prepared 10-hydroxycamptothecin-tetrandrine liposome complexes with 10-hydroxycamptothecin as the basic anticancer drug, tetrandrine and liposomes as carriers. In this article, an ultra-high performance liquid chromatography tandem mass spectrometry method for the analysis of 10-hydroxycamptothecin and tetrandrine in plasma has been developed, validated, and utilized to compare the pharmacokinetics of both drugs in the original dosage form and administered as liposome complexes. According to the pharmacokinetic parameters of mean residence time, half-life period and clearance rate, the 10-hydroxycamptothecin-tetrandrine liposome complexes prolongs the retention and circulation time of 10-hydroxycamptothecin in vivo, achieving a good sustained release effect. To the best of our current knowledge, the pharmacokinetic properties of 10-hydroxycamptothecin-tetrandrine liposome complexes in rats have not been reported yet. Our study can provide a helpful reference for further related study.

Synthesis, purification, and anticancer effect of magnetic Fe3O4-loaded poly (lactic-co-glycolic) nanoparticles of the natural drug tetrandrine.

Here, we have successfully synthesised and purified multifunctional PLGA-based nanoparticles by the co-encapsulation of an anticancer drug (tetrandrine) and a magnetic material (Fe3O4). The obtained Tet-Fe3O4-PLGA NPs had a uniform spherical shape with a particle size of approximately 199 nm and a negative surface charge of -18.0 mV, displaying a high encapsulation efficiency. Furthermore, TEM studies provided representative images of the purification process of the magnetic nanoparticles with MACS® technology. The MFM and VSM results indicated that both the Fe3O4 NPs and Tet-Fe3O4-PLGA NPs were superparamagnetic. The DSC spectrum demonstrated that Tet was successfully encapsulated within the PLGA-based nanoparticles. Significantly, the release studies revealed NPs had a relatively slower release rate than free Tet after 8 h's initial burst release, which had decreased from 98% to 65% after 24 h. In vitro cellular studies revealed that NPs could effectively penetrate into A549 cells and A549 multicellular spheroids to exert cytotoxicity, displaying a significantly high anti-proliferation effect. Moreover, western blot demonstrated that the co-loaded NPs had a higher anticancer activity by injuring lysosomes to activate the mitochondria pathway and induce A549 cell apoptosis. The magnetic characteristics and high anticancer activity support the use of Tet/Fe3O4 co-loaded PLGA-based nanoparticles as a promising strategy in the treatment of lung cancer.

Interaction Effects between Doxorubicin and Hernandezine on the Pharmacokinetics by Liquid Chromatography Coupled with Mass Spectrometry.

Doxorubicin (DOX) is an effective anti-tumor drug widely used in clinics. Hernandezine (HER), isolated from a Chinese medicinal herb, has a selective inhibitory effect on DOX multidrug resistance, making DOX more effective in treating cancer. The aim of this study was to investigate the effect of the interaction of HER and DOX on pharmacokinetics. Male Sparague-Dawley rats were randomly divided into three groups: a single DOX group, a single HER group, and a combination group. Plasma concentrations of DOX and HER were determined by the LC-MS/MS method at specified time points after administration, and the main pharmacokinetic parameters were estimated. The results showed that there were significant differences in the Cmax and AUC0-∞ of DOX in the single drug group and combined drug group, indicating that HER could improve the absorption of DOX. However, DOX in combination, in turn, reduced the free drug concentration of HER, possibly because DOX enhanced the HER drug-protein binding effect. The results could be used as clinical guidance for DOX and HER to avoid adverse reactions.

Cepharanthine Induces Autophagy, Apoptosis and Cell Cycle Arrest in Breast Cancer Cells.

BACKGROUND: Cepharanthine (CEP) is a biscoclaurine alkaloid extracted from Stephania cepharantha and has been shown to have an anti-tumour effect on different types of cancers. However, the anti-cancer effect of CEP on human breast cancer cells is still unclear. METHODS: We used MTT, clone formation, in vitro scratch, invasion and migration assays to confirm the inhibitory role of CEP on the proliferation of breast cancer cells. Flow cytometry, plasmid construction and western blot analysis were used to study the detailed mechanisms. RESULTS: Our study showed that CEP could inhibit cell proliferation by inducing autophagy, apoptosis, and G0/G1 cell cycle arrest of breast cancer cells. Furthermore, we found that CEP induced autophagy and apoptosis by inhibiting the AKT/mTOR signalling pathway. CONCLUSION: We found that CEP could inhibit growth and motility of MCF-7 and MDA-MB-231 breast cancer cell. Our study revealed an anti-tumour effect of CEP on breast cancer cells and suggests that CEP could be a potential new clinical therapy for breast cancer.

Determination of cepharanthine in rat plasma by LC-MS/MS and its application to a pharmacokinetic study.

CONTEXT: Cepharanthine (CPA) has been reported to possess a wide range of pharmacological activities. OBJECTIVE: This study investigates the pharmacokinetic characteristics after oral or intravenous administration of CPA by using a sensitive and rapid LC-MS/MS method. MATERIALS AND METHODS: A sensitive and rapid LC-MS/MS method was developed for the determination of CPA in Sprague-Dawley rat plasma. Twelve rats were equally randomized into two groups, including the intravenous group (1 mg/kg) and the oral group (10 mg/kg). Blood samples (250 µL) were collected at designated time points and determined using this method. The pharmacokinetic parameters were calculated. RESULTS: The calibration curve was linear within the range of 0.1-200 ng/mL (r = 0.999) with the lower limit of quantification at 0.1 ng/mL. After 1 mg/kg intravenous injection, the concentration of CPA reached a maximum of 153.17 ± 16.18 ng/mL and the t1/2 was 6.76 ± 1.21 h. After oral administration of 10 mg/kg of CPA, CPA was not readily absorbed and reached Cmax 46.89 ± 5.25 ng/mL at approximately 2.67 h. The t1/2 was 11.02 ± 1.32 h. The absolute bioavailability of CPA by oral route was 5.65 ± 0.35%, and the bioavailability was poor. DISCUSSION AND CONCLUSIONS: The results indicate that the bioavailability of CPA was poor in rats, and further research should be conducted to investigate the reason for its poor bioavailability and address this problem.

Preparation and evaluation of charged solid lipid nanoparticles of tetrandrine for ocular drug delivery system: pharmacokinetics, cytotoxicity and cellular uptake studies.

In this study, tetrandrine-loaded cationic solid lipid nanoparticles (TET-CNP) and solid lipid nanoparticles (TET-NP) were prepared by the emulsion evaporation-solidification at low temperature method. The particle size, zeta potential, and entrapment efficiency of TET-CNP and TET-NP were characterized. The results showed that the TET-CNP and TET-NP had average diameters of (15.29 ± 1.34) nm and (18.77 ± 1.23) nm with zeta potentials of (5.11 ± 1.03) mV and (-8.71 ± -1.23) mV and entrapment efficiencies of (94.1 ± 2.37)% and (95.6 ± 2.43)%, respectively. In vitro release studies indicated that the TET-CNP and TET-NP retained the drug entity better than tetrandrine ophthalmic solutions (TET-SOL). In the pharmacokinetics studies, the AUC values of TET-CNP and TET-NP were 1.96-fold and 2.00-fold higher than that of TET-SOL ( p < 0.05); the Cmax values of TET-CNP and TET-NP were 2.45-fold and 2.53-fold higher than that of the TET-SOL (p < 0.05), respectively. Cytotoxicity study showed that TET-CNP and TET-NP had no significant toxicity at low concentrations. Flow cytometry studies and confocal microscopy analysis demonstrated that calcein labeled NP (CA-NP) uptake by SRA 01/04 cells was much higher than those of calcein labeled CNP (CA-CNP) and calcein solution (CA-SOL).

Tumor-Targeted cRGD-Coated Liposomes Encapsulating Optimized Synergistic Cepharanthine and IR783 for Chemotherapy and Photothermal Therapy.

Background: Combination therapy offers superior therapeutic results compared to monotherapy. However, the outcomes of combination therapy often fall short of expectations, mainly because of increased toxicity from drug interactions and challenges in achieving the desired spatial and temporal distribution of drug delivery. Optimizing synergistic drug combination ratios to ensure uniform targeting and distribution across space and time, particularly in vivo, is a significant challenge. In this study, cRGD-coated liposomes encapsulating optimized synergistic cepharanthine (CEP; a chemotherapy drug) and IR783 (a phototherapy agent) were developed for combined chemotherapy and photothermal therapy in vitro and in vivo. Methods: An MTT assay was used to evaluate the combination index of CEP and IR783 in five cell lines. The cRGD-encapsulated liposomes were prepared via thin-film hydration, and unencapsulated liposomes served as controls for the loading of CEP and IR783. Fluorescence and photothermal imaging were used to assess the efficacy of CEP and IR783 encapsulated in liposomes at an optimal synergistic ratio, both in vitro and in vivo. Results: The combination indices of CEP and IR783 were determined in five cell lines. As a proof-of-concept, the optimal synergistic ratio (1:2) of CEP to IR783 in 4T1 cells was evaluated in vitro and in vivo. The average diameter of the liposomes was approximately 100 nm. The liposomes effectively retained the encapsulated CEP and IR783 in vitro at the optimal synergistic molar ratio for over 7 d. In vivo fluorescence imaging revealed that the fluorescence signal from cRGD-CEP-IR783-Lip was detectable at the tumor site at 4 h post-injection and peaked at 8 h. In vivo photothermal imaging of tumor-bearing mice indicated an increase in tumor temperature by 32°C within 200 s. Concurrently, cRGD-CEP-IR783-Lip demonstrated a significant therapeutic effect and robust biosafety in the in vivo antitumor experiments. Conclusion: The combination indices of CEP and IR783 were successfully determined in vitro in five cell lines. The cRGD-coated liposomes encapsulated CEP and IR783 at an optimal synergistic ratio, exhibiting enhanced antitumor effects and targeting upon application in vitro and in vivo. This study presents a novel concept and establishes a research framework for synergistic chemotherapy and phototherapy treatment.

Delivery of paclitaxel and berbamine by polymeric carriers to cure gastric cancer.

Successful chemotherapy needs to reduce the toxic side effects against normal tissues and avoid the detriments caused by intolerable solvents. Drug delivery systems using soluble polymeric nanoparticles tend to be the focus. In the current study, core-shell structure nanoparticles were prepared from block copolymer of methoxy poly(ethylene glycol)-polycaprolactone (mPE-PCL). Paclitaxel (PTX) and berbamine (BA) were incorporated into mPEG-PCL nanoparticles. It was found in our study that PTX and BA can be incorporated into the nanoparticles with high encapsulation efficiency. In vitro release study showed that PTX and BA were released from nanoparticles in a sustained manner. In vitro cytotoxicity studies indicated that PTX/BA coloaded nanoparticles (PTX/BA-np) show dose- and time-dependent cytotoxicity again BGC823 cells. Furthermore, intratumoral administration was applied to improve the tumor-targeted delivery in the in vivo evaluation. Compared with free drugs, PTX/BA-np exhibited superior antitumor effect by delaying tumor growth when delivered intratumorally. These results suggest that PTX/BA-np are effective to inhibit the growth of human gastric cancer and merit more research to evaluate the feasibility of clinical application.

Comparative effects of liensinine and neferine on the human ether-a-go-go-related gene potassium channel and pharmacological activity analysis.

Liensinine and neferine, a kind of isoquinoline alkaloid, can antagonize the ventricular arrhythmias. The human ether-a-go-go-related gene (hERG) is involved in repolarization of cardiac action potential. We investigated the effects of liensinine and neferine on the biophysical properties of hERG channel and the underlying structure-activity relationships. The effects of liensinine and neferine were examined on the hERG channels in the stable transfected HEK293 cells using a whole-cell patch clamp technique, western blot analysis and immunofluorescence experiment. The pharmacokinetics and tissue distribution determination of liensinine and neferine in rats were determined by a validated RP-HPLC method. Liensinine and neferine induced decrease of current amplitude in dose-dependent. Liensinine reduced hERG tail current from 70.3±6.3 pA/pF in control group to 56.7±2.8 pA/pF in the 1 µM group, 53.0±2.3 pA/pF (3 µM) and 17.8±0.7 pA/pF (30 µM); the corresponding current densities of neferine-treated cells were 41.9±3.1 pA/pF, 32.3±3.1 pA/pF and 16.2±0.6 pA/pF, respectively. Neferine had binding affinity for the open and inactivated state of hERG channel, liensinine only bound to the open state. The inhibitory effects of liensinine and neferine on hERG current were attenuated in the F656V or Y652A mutant channels. Neferine distributed more quickly than liensinine in rats, which was found to be in higher concentration than liensinine. Both liensinine and neferine had no effect on the generation and expression of hERG channels. In conclusion, neferine is a more potent blocker of hERG channels than liensinine at low concentration (<10 µM), which may be due to higher hydrophobic nature of neferine compared with liensinine. Neferine may be safety even for long-term treatment as an antiarrhythmic drug.

Preparation, characterization, pharmacokinetics and tissue distribution of solid lipid nanoparticles loaded with tetrandrine.

Tetrandrine (TET) is a poorly water-soluble bisbenzylisoquinoline alkaloid. In this study, TET solid lipid nanoparticles (SLNs) were prepared by a melt-emulsification and ultrasonication technique. Precirol(®) ATO 5, glyceryl monostearate, and stearic acid were used as the lipid matrix for the SLNs, while Lipoid E80, Pluronic F68, and sodium deoxycholate were used as emulsifying and stabilizing agents. The physicochemical characteristics of the TET-SLNs were investigated when it was found that the mean particle size and zeta potential of the TET-SLNs were 134 ± 1.3 nm and -53.8 ± 1.7 mV, respectively, and the entrapment efficiency (EE) was 89.57% ± 0.39%. Differential scanning calorimetry indicated that TET was in an amorphous state in SLNs. TET-SLNs exhibited a higher release rate at a lower pH and a lower release rate at a higher pH. The release pattern of the TET-SLNs followed the Weibull model. The pharmacokinetics of TET-SLNs after intravenous administration to male rats was studied. TET-SLN resulted in a higher plasma concentration and lower clearance. The biodistribution study indicated that TET-SLN showed a high uptake in reticuloendothelial system organs. In conclusion, TET-SLNs with a small particle size, and high EE, can be produced by the method described in this study. The SLN system is a promising approach for the intravenous delivery of tetrandrine.

Thirteen bisbenzylisoquinoline alkaloids in five Chinese medicinal plants: Botany, traditional uses, phytochemistry, pharmacokinetic and toxicity studies.

RELEVANCE: Bisbenzylisoquinoline (BBIQ) alkaloids are generally present in plants of Berberidaceae, Monimiaceae and Ranunculaceae families in tropical and subtropical regions. Some species of these families are used in traditional Chinese medicine, with the effects of clearing away heat and detoxification, promoting dampness and defecation, and eliminating sores and swelling. This article offers essential data focusing on 13 representative BBIQ compounds, which are mainly extracted from five plants. The respective botany, traditional uses, phytochemistry, pharmacokinetics, and toxicity are summarized comprehensively. In addition, the ADME prediction of the 13 BBIQ alkaloids is compared and analyzed with the data obtained. MATERIALS AND METHODS: We have conducted a systematic review of the botanical characteristics, traditional uses, phytochemistry, pharmacokinetics and toxicity of BBIQ alkaloids based on literatures collected from PubMed, Web of Science and Elsevier during 1999-2020. ACD/Percepta software was utilized to predict the pharmacokinetic parameters of BBIQ alkaloids and their affinity with enzymes and transporters. RESULTS: Botany, traditional uses, phytochemistry, pharmacokinetic and toxicity of 13 alkaloids, namely, tetrandrine, dauricine, curine, trilobine, isotrilobine, cepharanthine, daurisoline, thalicarpine, thalidasine, isotetrandrine, liensinine, neferine and isoliensinine, have been summarized in this paper. It can't be denied that these alkaloids are important material basis of pharmacological effects of family Menispermaceae and others, and for traditional and local uses which has been basically reproduced in the current studies. The 13 BBIQ alkaloids in this paper showed strong affinity and inhibitory effect on P-glycoprotein (P-gp), with poor oral absorption and potent binding ability with plasma protein. BBIQ alkaloids represented by tetrandrine play a key role in regulating P-gp or reversing multidrug resistance (MDR) in a variety of tumors. The irrationality of their usage could pose a risk of poisoning in vivo, including renal and liver toxicity, which are related to the formation of quinone methide during metabolism. CONCLUSION: Although there is no further clinical evaluation of BBIQ alkaloids as MDR reversal agents, their effects on P-gp should not be ignored. Considering their diverse distribution, pharmacokinetic characteristics and toxicity reported during clinical therapy, the quality standards in different plant species and the drug dosage remain unresolved problems.

Berbamine Suppresses the Progression of Bladder Cancer by Modulating the ROS/NF-κB Axis.

Berbamine (BBM), one of the bioactive ingredients extracted from Berberis plants, has attracted intensive attention because of its significant antitumor activity against various malignancies. However, the exact role and potential molecular mechanism of berbamine in bladder cancer (BCa) remain unclear. In the present study, our results showed that berbamine inhibited cell viability, colony formation, and proliferation. Additionally, berbamine induced cell cycle arrest at S phase by a synergistic mechanism involving stimulation of P21 and P27 protein expression as well as downregulation of CyclinD, CyclinA2, and CDK2 protein expression. In addition to suppressing epithelial-mesenchymal transition (EMT), berbamine rearranged the cytoskeleton to inhibit cell metastasis. Mechanistically, the expression of P65, P-P65, and P-IκBα was decreased upon berbamine treatment, yet P65 overexpression abrogated the effects of berbamine on the proliferative and metastatic potential of BCa cells, which indicated that berbamine attenuated the malignant biological activities of BCa cells by inhibiting the NF-κB pathway. More importantly, berbamine increased the intracellular reactive oxygen species (ROS) level through the downregulation of antioxidative genes such as Nrf2, HO-1, SOD2, and GPX-1. Following ROS accumulation, the intrinsic apoptotic pathway was triggered by an increase in the ratio of Bax/Bcl-2. Furthermore, berbamine-mediated ROS accumulation negatively regulated the NF-κB pathway to a certain degree. Consistent with our in vitro results, berbamine successfully inhibited tumor growth and blocked the NF-κB pathway in our xenograft model. To summarize, our data demonstrated that berbamine exerts antitumor effects via the ROS/NF-κB signaling axis in bladder cancer, which provides a basis for further comprehensive study and presents a potential candidate for clinical treatment strategies against bladder cancer.

Pharmacokinetics and safety of bromotetrandrine (BrTet, W198) after single-dose intravenous administration in healthy Chinese volunteers.

OBJECTIVE: To investigate the safety and pharmacokinetics of bromotetrandrine (BrTet, W198), a novel inhibitor of P-glycoprotein (P-gp), after single-dose i.v. infusion in healthy Chinese volunteers. METHODS: We conducted a randomized, dose-escalating, phase I clinical study for that purpose. Thirty healthy subjects received BrTet at the doses of 10, 20 or 30 mg/m(2) by i.v. infusion. Plasma and urine concentrations of bromotetrandrine were determined by using a liquid chromatography-tandem mass spectrometric (LC/MS/MS) method. AUC was calculated by the trapezoidal rule extrapolation method. C(max), T(max), t(1/2alpha), t(1/2beta), Cl and V(d) were compiled from the plasma concentration-time data. RESULTS: Bromotetrandrine was generally well tolerated at all doses. No serious or severe adverse events were found in the study. The pharmacokinetic parameters of BrTet after single i.v. infusion doses of BrTet 10, 20 and 30 mg/m(2) were as follows: T(max) were 1.5 h in three groups, C(max) were 24.79, 39.59 and 64.31 microg/L, t(1/2alpha) were 0.37, 0.29 and 0.30 h, t(1/2beta) were 62.88, 56.45 and 52.20 h. AUC(0-194h) were 345.83, 688.15 and 1096.28 microg h/L, Cl were 23.68, 25.69 and 25.66 L h/m(2), V(d) were 157.73,156.96 and 140.73 L/m(2). In urine, the total eliminate rate of originate compound was 0.61 +/- 0.19%. CONCLUSIONS: This study suggested that bromotetrandrine was well tolerated in healthy volunteers within the dose range evaluated. The pharmacokinetics parameters of bromotetrandrine indicated that the compound was rapidly distributed and accumulated in the tissues, and slowly cleared from plasma, which supported the use of BrTet for a once or twice dosing per chemotherapy cycle.

A novel controlled release tetrandrine-loaded PDLLA film: evaluation of drug release and anti-adhesion effects in vitro and in vivo.

To investigate the drug release and anti-adhesion effects of a TET (tetrandrine)-loaded PDLLA (poly-DL-lactide) film. Detection of TET release in vitro was carried out by high-performance liquid chromatography (HPLC) every 2 days following immersion of the tetrandrine-loaded PDLLA film in simulated body fluid until the TET content of the eluate could not be detected. For the in vivo test, TET-loaded PDLLA films were implanted into animal laminectomy models and positive and blank control groups were also set up. Postoperative serum tests, and macroscopic and histological analyses at 1, 4, 8, and 12 weeks, were used to assess the effects of the film. Statistical analyses were performed by one-way ANOVA. The drug release of the tetrandrine-loaded PDLLA film in vitro showed two phases with a second release peak. Ultimately, the duration of continuous delivery was up to 66 days and the cumulative delivery rate was up to 93.18%. Scores for the proliferation of epidural scars or adhesion of the dura mater in the test group were much lower than those for the two control groups. Histological analysis revealed the test group had fewer inflammatory cells and fibroblasts, as well as fewer extracellular collagen fibers, and a lower histology score than those of the two control groups at all time points. Tetrandrine-loaded PDLLA film is a novel controlled drug release and anti-adhesion material in vitro and in vivo.

Tetrandrine: a review of its anticancer potentials, clinical settings, pharmacokinetics and drug delivery systems.

OBJECTIVES: Tetrandrine, a natural bisbenzylisoquinoline alkaloid, possesses promising anticancer activities on diverse tumours. This review provides systematically organized information on cancers of tetrandrine in vivo and in vitro, discuss the related molecular mechanisms and put forward some new insights for the future investigations. KEY FINDINGS: Anticancer activities of tetrandrine have been reported comprehensively, including lung cancer, colon cancer, bladder cancer, prostate cancer, ovarian cancer, gastric cancer, breast cancer, pancreatic cancer, cervical cancer and liver cancer. The potential molecular mechanisms corresponding to the anticancer activities of tetrandrine might be related to induce cancer cell apoptosis, autophagy and cell cycle arrest, inhibit cell proliferation, migration and invasion, ameliorate metastasis and suppress tumour cell growth. Pharmaceutical applications of tetrandrine combined with nanoparticle delivery system including liposomes, microspheres and nanoparticles with better therapeutic efficiency have been designed and applied encapsulate tetrandrine to enhance its stability and efficacy in cancer treatment. SUMMARY: Tetrandrine was proven to have definite antitumour activities. However, the safety, bioavailability and pharmacokinetic parameter studies on tetrandrine are very limited in animal models, especially in clinical settings. Our present review on anticancer potentials of tetrandrine would be necessary and highly beneficial for providing guidelines and directions for further research of tetrandrine.

Liquid chromatographic/mass spectrometry assay of bromotetrandrine in rat plasma and its application to pharmacokinetic study.

A rapid and sensitive liquid chromatography-tandem mass spectrometric method (LC-MS/MS) for the determination of bromotetrandrine in rat plasma has been developed and applied to pharmacokinetic study in Sprague-Dawley (SD) rats after a single oral administration. Sample preparation involves a liquid-liquid extraction with n-hexane-dichlormethane (65:35, containing 1% 2-propanol isopropyl alcohol, v/v). Bromotetrandrine and brodimoprim (internal standard, IS) were well separated by LC with a Dikma C18 column using methanol-ammonium formate aqueous solution (20 mm) containing 0.5% formic acid (60:40, v/v) as mobile phase. Detection was performed on a triple quadrupole mass spectrometer in multiple reaction monitoring mode. The ionization was optimized using ESI+ and selectivity was achieved using MS/MS analysis, m/z 703.0 --> 461.0 and m/z 339.0 --> 281.0 for bromotetrandrine and IS, respectively. The present method exhibited good linearity over the concentration range of 20-5000 ng/mL for bromotetrandrine in rat plasma with a lower limit of quantification of 20 ng/mL. The intra- and inter-day precisions were 2.8-7.5% and 3.2-8.1%, and the intra- and inter-day accuracy ranged from -4.8 to 8.2% and -5.6 to 6.2%, respectively. The method was successfully applied to a pharmacokinetic study after a single oral administration to SD rats with bromotetrandrine of 50 mg/kg.

Berbamine induces Fas-mediated apoptosis in human hepatocellular carcinoma HepG2 cells and inhibits its tumor growth in nude mice.

Berbamine, a natural compound from the plant Berberis amurensis, is a traditional Chinese medicine mainly used in stimulating normal hematopoiesis in clinic. Our previous studies demonstrated that berbamine has anti-leukemia activity. In this study, we investigated the anticancer activity of berbamine against human hepatocellular carcinoma (HCC) HepG2 cells in vitro and in vivo. Berbamine treatment decreased the cell growth in a dose-dependent manner with an IC(50) value of 34.5 +/- 0.5 microM. Flow cytometric analysis of apoptosis using Annexin V/propidium iodide staining showed that the percentage of apoptotic cells was increased in a time-dependent manner. Berbamine treatment increased the expression level of Fas and P53, caused depolarization of mitochondrial membrane and decrease of membrane potential, and activated caspase-3, -8, and -9 in HepG2 cells. Berbamine-induced apoptosis could be blocked by the broad caspase inhibitor z-VAD-fmk. HepG2 human HCC xenograft mice treated with berbamine showed a significant reduction in tumor growth rates compared to saline-treated mice. These studies suggest that berbamine exerts anticancer effects on human HCC HepG2 cells in vivo and in vitro, the induction of p53 and the activity of the Fas apoptotic system may participate in the anticancer activity of berbamine in HepG2 cells.

Evaluation of tetrandrine sustained release calcium alginate gel beads in vitro and in vivo.

An approach for the preparation of tetrandrine sustained release calcium alginate gel beads was described. In vitro the release of tetrandrine from sustained release dosage forms went on a time of 12 hours which fitted non-Fickian diffusion with matrix erosion significantly. In vivo the plasma concentration of tetrandrine extended preparation given in dogs reached Cmax 2.67+/-0.69 microg/ml approximately at 5.67+/-0.58 h after oral administration. The AUC0-->24 and AUC0-->infinity were 24.64+/-6.77 mg.h/l and 29.75+/-5.30 mg.h/l, respectively. The elimination half-time was 9.6+/-2.40 h. While a favorable correlation existed between in vitro and in vivo with a correlative coefficient of 0.9798 through linear regression. An investigation on the quantitative relationship between in vitro release and in vivo absorption is a highly necessary work guided for manufacture, optimization and in vivo evaluation of sustained release dosage by means of in vitro release or dissolution tests.