Transport of aripiprazole across Caco-2 monolayer model / 药学学报

This study aimed to investigate the transport characteristics of aripiprazole. A human intestinal epithelial cell model Caco-2 cell in vitro cultured had been applied to study the transport of aripiprazole. The effects of time, concentration of donor solutions, pH, temperature and P-glycoprotein inhibitor on the transport of aripiprazole were investigated. The determination of aripiprazole was performed by HPLC. It is concluded that aripiprazole is transported through the intestinal mucosa via a passive diffusion mechanism primarily, coexisting with a carrier-mediated transport. The transport of aripiprazole is positively correlated to transport time, pH, and temperature. Papp increased with donor concentrations up to 10 microg x mL(-1), and then decreased for higher concentrations. The P-glycoprotein inhibitor cyclosporine A significantly enhanced the transport amount of aripiprazole.

Effect of carbon dioxide pneumoperitoneum-laparoscopic surgery on tumor seeding and metastases in endometrial cancer / 中南大学学报(医学版)

OBJECTIVE@#To explore the influence of carbon dioxide pneumoperitoneum-laparoscopic surgery on tumor cell seeding and metastases in endometrial cancer.@*METHODS@#Twenty patients with endometrial cancer who underwent laparoscopic surgery and 10 patients with endometrial cancer who underwent laparotomic surgery were enrolled. Each patient was in preoperative clinical StageIand the uterus size in each patient was less than 12 weeks of pregnancy. Carbon dioxide pneumoperitoneum was established and maintained with CO2 insufflation at 4 approximately 6 L/min and intraperitoneal pressure of 13 mmHg with an automatic pneumoperitoneum machine. Cytologic examination of peritoneal fluid(at the beginning and end of the operation), CO2 filtrated gas and the lavage fluid of instruments during the laparoscopic surgery were performed. The protein expressions of E-cadherin,beta-catenin,P-selectin,matrix metalloproteinase-2(MMP-2),vascular endothelial growth factor (VEGF),and CD44v6 in tumor tissues before and after the operation were detected by DAKO Envision.@*RESULTS@#There were no case of positive washing cytology in the peritoneal fluid,CO2 filtrated gas, and the lavage fluid of instruments during the laparoscopic surgery. The expressions of E-cadherin and beta-catenin proteins were obviously abnormal in endometrial cancer. The abnormal expressions of E-cadherin and beta-catenin protein between the pre- and post-operations were not significantly different in both the laparoscopic group and the laparotomic group(P>0.05).The changes of abnormal expressions of E-cadherin and beta-catenin protein were no statistical difference between the two groups(P>0.05). The positive protein expressions of P-selectin,MMP-2,VEGF,and CD44v6 were not significantly different between the pre- and post-operations both in the laparoscopic group and the laparotomic group(P>0.05),and there was also no significant difference between the laparoscopic group and the laparotomic group(P>0.05).The follow-up period in the laparoscopic group was 7 approximately 19 (14.25+/-3.65) months and 7 approximately 19 (13.10+/-4.23) months in the laparotomic group. One patient got infection in the urinary system in the laparoscopic group and one patient had lower extremity venous thrombosis in the laparoscopic group.No recurrence was detected in both groups.@*CONCLUSION@#Laparoscopic surgery for endometrial cancer has no effect on protein expressions of E-cadherin,beta-catenin,P-selectin,MMP-2,VEGF,and CD44v6 in tumor tissues. No evidence has been found that CO2 pneumoperitoneum-laparoscopic surgery may favor endometrial cancer cell seeding and metastases.

Preparation, characterization of paclitaxel-loaded Pluronic P105 polymeric micelles and in vitro reversal of multidrug resistant tumor / 药学学报

Drug delivery system (DDS) is a novel approach to overcome multidrug resistance (MDR) in tumors nowadays. This work was designed to investigate a new micellar delivery system for in vitro reversal of resistant ovarian tumor cells, based on a nonionic triblock copolymer Pluronic P105 and paclitaxel (PTX). The PTX-loaded polymeric micelles (P105/PTX) were prepared by thin film-hydration methods. Based on the results of single factor experiments, the P105/PTX micelle formulation was optimized by employing the central composite design-response surface methodology. The physico-chemical properties of the P105/PTX micelles were characterized, including micelle size, drug loading coefficient, in vitro release behavior, etc. The cytotoxicity of the P105/PTX micelles was assessed against human ovarian tumor cell line, SKOV-3/PTX, by a standard 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl (MTT) assay. In order to understand the possible mechanism of Pluronic effects in resistant tumor cells, cellular uptake study of micellar PTX or Rhodamine-123 (R-123) was also carried out. The results showed that the micelle size was about 24 nm with drug loading coefficient of 1.1% and PTX concentration of 700 microg x mL(-1). The cumulative release amount of PTX from the P105/PTX micelles was only 45.4% in 6 h (P < 0.05) and 79.6% in 24 h, whereas Taxol injection in 6 h released 95.2% PTX. The IC50 values of the P105/PTX micelles and Taxol injection against SKOV-3/PTX were 1.14 and 5.11 microg x mL(-1), and resistance reversion index (RRI) was 9.65 and 2.15, respectively. The micellar PTX or R-123 exhibited a significant increase in cellular uptake in resistant SKOV-3/PTX cells compared with free PTX or R-123. These results indicated that PTX could effectively be solubilized by Pluronic P105 block copolymers via thin film-hydration process and formulation optimization, producing nano-scale polymeric micelles with sustained release property in vitro. The P105/PTX micelles were effectively able to reverse resistance to PTX in SKOV-3/PTX tumor cells compared with Taxol injection or free PTX solution, and the enhanced cytotoxicity in the resistant SKOV-3/PTX cell was related to the improved cellular uptake of PTX by Pluronic P105 copolymers.

Physicochemical stability and purification technology of caffeic acid tetramer from Arnebia euchroma / 中国中药杂志

<p><b>OBJECTIVE</b>To purify caffeic acid tetramer (CAT) with macroporous resin on the basis of its fundamental physicochemical stability research.</p><p><b>METHOD</b>The changes of CAT content were compared by HPLC method before and after the purification process, or while other conditions were altered.</p><p><b>RESULT</b>LK001 was the best one among 7 kinds of macroporous resin in regard of purifying ability. The optimum absorbing technology was the solution concentration at 10 g x L(-1), pH at 4.5, and the flow rate at 3 BV x h(-1). The best eluting technology was 45% ethanol as eluting agent, pH at 5.0, eluting volume at 50 mL after applying super-purified water and 20% ethanol. The yield of product was 3. 6 percent, and the active compound CAT was 58 percent in the product.</p><p><b>CONCLUSION</b>Macroporous resin LK001 is effective in enriching CAT from the crude extracts, thus this method of purification is advisable.</p>

Significant role of poloxamer in drug transport across blood-brain barrier / 药学学报

Poloxamers are found to be an efficient adjuvant with multiple effects and are applied generally in pharmaceutical field. In recent years, it is investigated that poloxamers can increase the permeability of a broad spectrum of drugs through blood-brain barrier (BBB) by means of manifold mechanisms included: (1) inhibiting P-glycoprotein and multidrug-resistance associated protein efflux systems on BBB; (2) adsorbing different apolipoproteins in plasma on the surface of poloxamer-coated nanoparticles, which could interact with BBB through different receptors and mechanisms; (3) connecting to specific ligands and monoclonal antibodies to cross the BBB via specific endogenous transporters localized within the brain capillary endothelium. Significant roles of poloxamer in drug transport across BBB are considered in this review which provides for important guidance to the design of brain-targeted drug delivery system.

Screening of Panax notoginsenoside water in oil microemulsion formulations and their evaluation in vitro and in vivo / 药学学报

Water in oil (W/O) microemulsion formulation was developed to enhance intestinal absorption of ginsenoside Rb1 (Rb1) of panax notoginseng (PNS). Effects of W/O microemulsions on pharmacokinetics after intraduodenal administration, membrane fluidity and membrane transport of Rb, were studied in rats, liposomes and parallel artificial membrane permeability assay (PAMPA), respectively. Soybean phospholipids/ethanol (SP/EtOH) was selected as surfactant/cosurfactant, together with PNS 400 mg x mL(-1) solution and various kinds of oils, to prepare 11 W/O microemulsions. Most of the microemulsions can enhance Rb1 intestinal absorption significantly. Besides surfactant/cosurfactant, oil also had an effect on the enhanced absorption and the order of enhancement was as follows: glyceryl laurate approximately = isopropyl myristate > isopropyl palmitate > 2-ethylhexanol palmitate. The effection of absorption enhancement by the long chain glyceride ( > C14) is lower than that by the medium chain glyceride (C8 - C14). Most of W/O microemulsions were found to enhance the membrane fluidity of liposomes to different extents. In PAMPA analysis, efficient permeability coefficient (Pe) of diluted-microemulsion (D-ME) is mostly higher than that of PNS solution, which indicated the components of microemulision can facilitate the membrane permeability of the drug. Meanwhile, linearity correlation between Pe and ratio of relative bioavailability (Fr) was acquired for undiluted microemulison (ME). Therefore, W/O microemulsions can enhance intestinal absorption of Rbr, and this effect may be attiributed to its enhancement on membrane fluidity to a certain degree. PAMPA analysis could be brought into not only the investigation of membrane transport of crude drug, but also conditioned preformulation research (e.g. absorption enhancer etc.).

Comparison between the characteristics of absorption and pharmacokinetic behavior of ginsenoside Rg1 and ginsenoside Rb, of Panax notoginseng saponins / 药学学报

To compare the characteristics of absorption and pharmacokinetic behavior of ginsenoside Rg1 (Rg1) with ginsenoside Rb1 (Rb1) of panax notoginseng saponins (PNS), bile excretion of both Rg1 and Rb1 were studied after i.v. and i.g. of PNS solution. Plasma protein binding ratios were studied using equilibrium dialysis method, and referred to pharmacokinetic parameters. It shows that (61.48 +/- 18.30)% dose of Rg1 and (3.94 +/- 1.49)% dose of Rb1 were separately excreted into bile 10 hours after i.v. administration (PNS 50 mg x mL(-1)), and (0.91 +/- 0.51)% dose of Rg1 and (0.055 +/- 0.02)% dose of Rb1 were excreted into bile 12 hours after i.g. administration (PNS 1 500 mg x mL(-1)). Plasma protein binding degrees of Rg1 and Rb1 were 6.56% - 12.74% and 80.1% - 89.69%, respectively. Stomach, intestinal and hepatic throughput efficiency (F(S), F1 and F(H)) for Rg1 were 49.85%, 13.05%, 50.56%, respectively, and 25.82%, 4.18%, 65.77% for Rb1. Therefore, poor intestinal absorption is a primary reason for the low bioavailability of both Rg1 and Rb1. Rg1 possesses relatively high bile excretion and low plasma protein binding rate, in contrast, Rb1 possesses low bile excretion and high plasma protein binding rate. Membrane permeability and elimination rate of Rb1 were lower than that of Rg1, meanwhile, longer MRT and bigger AUC could be found for Rb1.

Effect of self-microemulsifying system on cell tight junctions / 药学学报

<p><b>AIM</b>To study the effect of negatively charged and positively charged self-microemulsifying systems (SMES) on the cellular tight junction complex was to be investigated at molecular cell level.</p><p><b>METHODS</b>Human intestinal epithelial Caco-2 cell model was established. Effect of formulations on the transepithelial electrical resistance (TEER) and permeability of the paracellular transport marker mannitol were measured to evaluate the cell integrity. Changes in subcellular localization of the tight junction protein zona occludens 1 (ZO-1) and cytoskeleton protein actin by immunofluorescence were also assessed after treatment of two SMESs in different dilutions.</p><p><b>RESULTS</b>The TEER of cell monolayers was not markedly affected by negatively charged SMES in different dilutions. The positively charged SMES could significantly decrease the TEER (P < 0.05) in three dilutions. The full recovery of TEER was found after the treatment of lower dilution for 2 h, then cultured for 48 h, while the recovery of TEER was 81.3% of control in 1 : 50 dilution. Two SMESs could enhance the apparent permeability coefficient of mannitol (2.9 - 64.6 folds), which depended on the dilution times. The immunofluorescent results indicated that the distribution of ZO-1 and actin were discrete in cell membrane after the treatment of formulation. Since the positively charged microemulsion could bind to the epithelial cell membrane by electrostatic interaction, the actin of the cells undergone some kind of stress stimulated by the higher concentration of microemulsion was more markedly affected than the negatively charged SMES. Effect of formulations on ZO-1 and actin relied on the dilution.</p><p><b>CONCLUSION</b>SMES is able to enhance the paracellular transport marker mannitol. The mechanism of opening of tight junctions by SMES might be the change of distribution of ZO-1 and actin.</p>

Mechanism of oral absorption of panaxnotoginseng saponins / 药学学报

<p><b>AIM</b>To study the mechanism of absorption after oral administration of panaxnotoginseng saponins (PNS).</p><p><b>METHODS</b>Caco-2 cells and rat models were applied to evaluate the degradation of both ginsenoside Rb1 (Rb1) and ginsenoside Rg1 (Rg1) in PNS in gastrointestinal lumen, and the transport mechanism of PNS across the intestinal mucosa, and the barrier function of stomach, intestine and liver involved in absorption process.</p><p><b>RESULTS</b>Rb1 and Rg1 proved to be readily eliminated in stomach, but stable in relatively neutral circumstance. Both Rb1 and Rg1 in PNS, especially for Rb1, degraded significantly in the contents of large intestine. However, both of them kept mainly intact in the contents of small intestine. Uptake of both Rb1 and Rg1 by Caco-2 cell monolayer was inhibited at low temperature, but not by cyclosporine A, and the change in the apical pH showed no pronounced effect. Uptake and transport were non-saturable and increased linearly with increasing of concentrations of Rb1 and Rg1 over the range of concentration tested, which indicated a passive transport. There was no significant difference of absorption characteristic between monomer (Rb1 and Rg1) and mixture (PNS). Uptake amount of Rg1 [(1.07 +/- 0.16) microg x mg(-1) (protein)] (C0 = 1 mg x mL(-1)) in Caco-2 cells was a little higher than that of Rb1 [(0.77 +/- 0.03) microg x mg(-1) (protein)] (C0 = 1 mg x mL(-1)). Meanwhile, apparent permeability coefficient of (5.9 +/- 1.0) x 10(-8) cm x s(-1) (C0 = 1 mg x mL(-1)) for Rb1 and (2.59 +/- 0.17) x 10(-7) cm x s(-1) (C0 = 1 mg x mL(-1)) for Rg1 from apical compartment to basolateral compartment predicted an incompletely absorption. Transports of both Rb1 and Rg1 were not influenced by cyclosporine A. The investigation on the pharmacokinetic behavior of Rb1 and Rg1 after different routes of administration to rats showed that the absolute bioavailability after peroral (po), intraduodenal (id), and portal venous (pv) administration is 0.71% , 2.75% and 65.77% respectively for Rb1, and 3.29%, 6.60% and 50.56% respectively for Rg1.</p><p><b>CONCLUSION</b>Transport across Caco-2 cell monolayer for PNS (include Rb1 and Rg1) is a simple passive diffusion process. No efflux transporters in Caco-2 cells and other components in PNS showed effects on it. The elimination in stomach, large intestine and liver contributed to the low bioavailability of PNS, but the low membrane permeability might be a more important factor dominating the extent of absorption.</p>

Expression of cylooxygenase-2 in endometriosis / 中南大学学报(医学版)

OBJECTIVE@#To investigate the expression of cyclooxygense-2 (COX-2) in eutopic and ectopic endometrium in ovarian endometriosis.@*METHODS@#Thirty patients with ovrian endometriosis, 10 with ovarian chocolate cysts and 27 normal controls were enrolled it determine the expression of COX-2 immunohistochemically in eutopic or ectopic endometrium or healthy endometrial tissues.@*RESULTS@#The immunoreactivities of COX-2 were found in epithelial cells and stromal cells in eutopic endometrium. The expression of COX-2 in the epithelial cells in the secretory phase was higher than that in the proliferative phase in the control group and ovarian endometriosis group (P 0. 05). The expression of COX-2 in eutopic and ectopic endometrium in the ovarian endometriosis group was higher than that in the control group (P 0. 05).@*CONCLUSION@#The increased COX-2 expression in eutopic and ectopic endometrium in ovarian endometriosis may he related to its pathology.

Effect of progesterone on the secretion of matrix metalloproteinase-2 and matrix metalloproteinase-9 in human ectopic endometrial stromal cells / 中南大学学报(医学版)

OBJECTIVE@#To determine the effect of progesterone on the secretion of matrix metalloproteinase-2 (MMP-2) and matrix metalloproteinase-9 (MMP-9) in ectopic endometrial stromal cells.@*METHODS@#Ectopic endometrial stromal cells were obtained from 17 patients with endometriosis. Endometrial stromal cells were obtained from 12 patients with endometriosis and 14 cases of controls. Ectopic endometrial stromal cells of 15 cases were treated with progesterone. Culture supernatants of these stromal cells were analyzed for MMP-2 and MMP-9 by zymography.@*RESULTS@#Endometriotic stromal cells released significantly higher levels of MMP-2 and MMP-9 than endometrial stromal cells from women with and without endometriosis. Progesterone at 10(-9) mol/L caused endometriotic stromal cells a significant reduction MMP-2 and MMP-9 levels. When progesterone concentration was increased from 10(-9) mol/L to 10(-7) mol/L, the release of MMP-9 was almost completely inhibited, wherease that of MMP-2 was not completely inhibited.@*CONCLUSION@#Progesterone may inhibit the secretion of MMP-2 and MMP-9 in ectopic endometrial stromal cells, especially MMP-9.

The pharmacokinetics and pharmacodynamics of intranasal preparation of Panax notoginseng Saponins / 药学学报

<p><b>AIM</b>To investigate the pharmacokinetic course of intranasal powders of Panax notoginseng Saponins (PNS) in a rat model and its protective effects against cardio-cerebrovascular diseases administrated in the form of its suspension.</p><p><b>METHODS</b>After administration, Rgl concentration in the serum was analyzed by HPLC and the absolute bioavailability was calculated. The protective effects against cardia-cerebrovascular diseases were studied on actue myocardial infarction model in rats built by occlusion of left coronary artery and cerebral ischemia-reperfusion model in gerbils built by occlusion of bilateral common carotid artery (CCA).</p><p><b>RESULTS</b>The in vivo course of Rgl in rats conformed to two-compartment model after intranasal administration of PNS suspension and the absolute bioavailability was 103.56%. The suspension significantly reduced myocardial infarct size induced by occlusion of the left coronary artery, alleviated cerebral edema and the stroke symptoms induced by occlusion of bilateral common carotid artery (CCA). And the effects were dose-dependent, the higher dose, the better effects.</p><p><b>CONCLUSION</b>The results of pharmacokinetics and pharmacodynamics demonstrated that PNS intranasal preparation has a pretty prospect to develop.</p>

9-nitrocamptothecin nanostructured lipid carrier system: in vitro releasing characteristics, uptake by cells, and tissue distribution in vivo / 药学学报

<p><b>AIM</b>To study the release and cell uptake characteristics of 9-nitrocamptothecin (9-NC) nanostructured lipid carrier system (NLC) in vitro and its tissue distribution characteristics in vivo.</p><p><b>METHODS</b>Mouse peritoneal macrophages were used to investigate the uptake of nanoparticles by cells in vitro. The tissue distribution of 9-nitrocamptothecin solution and stealth nanostructured lipid carrier system (S-NLC) was determined after intravenous administration to mice at a single dose of 1.5 mg kg(-1). The release and crystalloid characteristics were also investigated.</p><p><b>RESULTS</b>X-ray diffraction spectrum showed that 9-NC probably was amorphous in S-NLC. The liquid lipid did not change the characteristics of the solid matrix in nanoparticles. The in vitro release and cell uptake characteristics of stealth and non-stealth 9-NC-NLC were investigated, separately. The results showed that the stealth 9-NC-NLC had sustained-release characteristics and could resist the absorption effect of the additional plasmas to a certain extent. In addition, the cell uptake percentage of stealth 9-NC-NLC was much lower than that of the non-stealth ones. The tissues distribution results showed that 9-NC in the S-NLC was mainly found in the lung, liver, pancreas and ovary/uterus, while the quantity of 9-NC was much lower in heart and kidney. The AUQ(0-t), of S-NLC in blood, ovary/uterus, pancreas, liver and lung were higher than that of 9-nitrocamptothecin solution. The weight-average drug targeting efficiency (Te*) of S-NLC in liver and lung were significantly higher than that of 9-nitrocamptothecin solution. The mean residence times (MRT) of S-NLC was 44 h, while that of 9-nitrocamptothecin solution was 8 h. Therefore, S-NLC showed obvious targeting effects on liver and lung.</p><p><b>CONCLUSION</b>S-NLC with PEG flexible chains has sustained-release characteristics and can prolong its circulation in blood and have good targeting efficiency on liver and lung.</p>

The in vitro kinetics of uptake, transport and efflux of 9-nitrocamptothecin in Caco-2 cell model / 药学学报

<p><b>AIM</b>To study the kinetics of uptake, transepithelial transport and efflux of 9-nitrocamptothecin (9-NC).</p><p><b>METHODS</b>A human intestinal epithelial cell model Caco-2 cell in vitro cultured had been applied to study the kinetics of uptake, transport and efflux kinetics of 9-NC at small intestine. The effects of time, pH, temperature and P-glycoprotein inhibitors on the uptake of 9-NC were investigated. The determination of 9-NC was performed by HPLC.</p><p><b>RESULTS</b>The uptake and absorption of 9-NC were passive diffusion as the dominating process. The uptake of 9-NC is positively correlated to uptake time, and negatively correlated to pH and temperature. The inhibitors, cyclosporine A and verapamil, significantly enhanced the uptake amount of 9-NC (P < 0.05). P(app) of Basolateral to Apical was much more than that of Apical to Basolateral (2.6-6.9 fold). The efflux of 9-NC was fitted to apparent two-order process. The m0 [(148.0 +/- 2.2) pmol x cm(-2)] and the efflux rate (41.1 pmol x cm2 min(-1)) on Apical side were higher than the m0 [(121 +/- 7) pmol x cm(-2)] (P < 0.05) and the efflux rate (29.2 pmol x cm2 x min(-1)) on Basolateral side (P < 0.01).</p><p><b>CONCLUSION</b>The uptake and absorption of 9-NC were passive diffusion as the dominating process. P-glycoprotein had strong efflux effects on the uptake and transepithelial transport of 9-NC.</p>

Studies on formulations of Panax notoginsenosides for intranasal administration / 药学学报

<p><b>AIM</b>To develop high bioavailability preparations without irritation for Panax notoginsenosides.</p><p><b>METHODS</b>The effects of some additives such as microcrystalline cellulose, beta-cyclodextrin and hydroxypropyl cellulose on drug in the preparations were examined.</p><p><b>RESULTS</b>Saponins of Panax notoginseng (PNS) was absorbed in rabbits more when administered intranasally than through other routines, and the formulations including MCC both gave high bioavailability and low irritation.</p><p><b>CONCLUSION</b>Bioavailability of Panax notoginsenosides can be increased through changing routine of administration and formulations.</p>