ABSTRACT
Inductively coupled plasma mass spectrometry (ICP-MS) was applied to determine the concentrations of lead (Pb), cadmium (Cd) and arsenic (As) in Lindera aggregata (Sims) Kosterm. The physiologically based extraction test (PBET) digestion in vitro/Caco-2 cell model was established to investigate the bioaccessible contents of Pb, Cd and As in decoction of Lindera aggregata (Sims) Kosterm. The target-organ toxicity dose modification of HI method (TTD) was used to evaluate the cumulative risk caused by the combined exposure of the total levels of Pb, Cd and As in Lindera aggregata (Sims) Kosterm. and the bioaccessible contents in the decoction. The results showed that the total contents of Pb, Cd and As in 4 batches of samples were in the range of 2.901-3.872, 1.299-1.800 and 0.062-0.216 mg·kg-1, respectively. After transportation by Cacco-2 cells, the bioaccessible contents of Pb, Cd, and As in the decoction were in the range of 0.045-0.080, 0.070-0.112 and 0.004-0.018 mg·kg-1. The results of risk assessment showed that calculated by the total amounts of heavy metals in the Lindera aggregata (Sims) Kosterm., for the end points of nervous system, the cumulative risks of co-exposure of heavy metals in 3 batches of samples were of concern. After decoction and transportation by Caco-2 cells, for the end points of cardiovascular system, blood, nervous system, kidney and testis, the TTD modification of HI values of all batches of samples were less than 1, and the health risks were acceptable. The study provided methodology basis for a more objective assessment of the health risks of heavy metals and harmful elements in traditional Chinese medicine and for a more scientific limit standard of heavy metals and harmful elements.
ABSTRACT
Objective: To evaluate the effect of low molecular weight chitosan (LMW-CTS) and its nanoparticles (LMW-CTS-NPs) on the intestinal permeability of Panax notoginseng saponins (PNS) by using Caco-2 cell model. Methods: LMW-CTS was prepared by combining chitosanase hydrolysis combined with ultrafiltration separation technology, and molecular weight of LMW-CTS was determined by using permeation gel chromatography (GPC). LMW-CTS-NPs were prepared by ionic gel method, and characterized by scanning electron microscopy, nano particle sizer, and flourier transformation infrared spectroscopy. Caco-2 cell model was established and validated to evaluate the effects of LMW-CTS and LMW-CTS-NPs on the intestinal permeability of PNS. Results: LMW-CTS has a molecular weight of 5 760 and a polydispersity coefficient of 1.42. LMW-CTS-NPs have a round shape and narrow particle size distribution, with an average particle size of 115.5 nm and zeta potential of +37.1 mV. The apparent permeability coefficients (Papp, AB→BL) of PNS was less than 1 × 10-6 cm/s, indicating a poor permeability. In LMW-CTS group, the Papp of R1 and Rg1 was increased by 17.83% and 20.29%, respectively, but no significant effect of promotion was observed on other components. However, the Papp of R1, Rg1, Re, Rb1, and Rd in LMW-CTS-NPs group was increased by 35.66%, 23.28%, 29.41%, 37.99%, and 36.00%, respectively, compared tothe control group. Conclusion: LMW-CTS can significantly promote the intestinal mucosal permeability of R1 and Rg1 in PNS, but has no significant effect on Re, Rb1, and Rd. LMW-CTS-NPs significantly increased the permeability of the major monomer saponin components in PNS. Namely, the intestinal permeability of PNS can be further improved by transforming LMW-CTS into LMW-CTS-NPs.
ABSTRACT
OBJECTIVE: To study the absorption mechanism of baicalin (BA) and baicalin solid lipid nanoparticles (BA SLN) by establishing an in vitro Caco-2 cell model. METHODS: A Caco-2 cell model was established. The appropriate concentration of BA and BA SLN in Caco-2 cell monolayer model was screened by CCK-8 method and LDH method. The content of BA was determined by high performance liquid chromatography, and the effects of time, concentration, temperature and endocytosis inhibitor on the uptake of BA and BA SLN were studied by this model. The transport of BA and BA SLN in the presence or absence of efflux inhibitors was also investigated. The expression of efflux protein was detected by Western blot. RESULTS: At 50-150 μg·mL-1, the uptake of BA and BA SLN was concentration-dependent; at 4 to 37 ℃, the uptake of BA and BA SLN increased with increasing temperature; endocytosis inhibitor influenced the cellular uptake of BA SLN; multidrug resistance-associated protein 2 (MRP2) inhibitors and breast cancer resistance protein (BCRP) inhibitors significantly reduced BA efflux, but did not affect BA SLN efflux; blank SLN and BA SLN can reduce the expression of MRP2 and BCRP in cells. CONCLUSION: BA is taken up and transported by small intestinal epithelial cells in a passive manner, and may be accompanied by energy dependence, which is related to MRP2 and BCRP efflux. BA SLN can significantly increase the uptake of drugs in the Caco-2 cell model, which may be related to the increase of endocytic pathway uptake and inhibition of extracellular repressor expression inhibition drug efflux.
ABSTRACT
Objective To investigate the influence of deoxyschizandrin (Deo) on P-glycoprotein (P-gp).Methods The effect of P-gp on Deo (20,40,80 μg·mL-1) was studied in the Caco-2 cell model in vitro,and the apparent permeability coefficient (Papp) of Deo (20-160 μg·mL-1) on a P-gp substrate,rhodamine123 or cyclosporine A,was calculated.Healthy male Sprague-Dawley rats were randomly divided into five groups:blank control group,verapamil group,low-,medium-and high-dose Deo group (8 rats in each group).Rats in the low-,medium-and high-dose Deo group were intragastrically administered once daily with Deo at 8,16 and 32 mg·kg-1 for 3 consecutive days,while rats similarly received gavagewith verapamil (4 mg·kg-1) in the verapamil group and equal volume of purified water in the blank control group.Thirty minutes after the rats were treated with their respective drugs,rhodamine123 (5 mg· kg-1) was orally administrated.Then the pharmacokinetic profiles of rhodamine 123 were analyzed to evaluate the inhibitory ability of Deo on P-gp in vivo.Results The bidirectional transport rates of Deo (20,40,80 μg·mL-1) were similar,with non-selectivity.Deo (20-160 pg·mL-1)significantly inhibited the basolateral→apical(BL→AP) directional transports of rhodamine 123 and cyclosporine A in Caco-2 cell model (P ＜ 0.05) in a concentration-dependent manner.And Deo (8-32 mg· kg-1) also dose-dependently decreased the peak concentrations (Cm.) and the area under the plasma concentration-time curve (AUC0-t) of Rho123.Conclusion Deo can inhibit P-gp in vitro and in vivo,but it is not a P-gp substrate.
ABSTRACT
Objective:To investigate the effects of schizandrin B on P- glycoprotein by a classical in vitro cell model. Methods:Caco-2 cell model was used as the carrier,and rhodamine 123 and cyclosporin A were employed as the P-gp substrates, the transmembrane transportation of schizandrin B,rodamine 123 and cyclosporin A were detected by HPLC and a liquid scintillation counting assay,and the apparent permeability coefficient and permeability directional ratio were calculated. Results:The bidirectional transportation rates of schizandrin B(20 μg·ml -1 ,40 μg·ml -1 and 80μg·ml-1 )were similar,and showed non-selective difference. Schizandrin B(20-160 μg ·ml -1 )significantly inhibited the BL → AP directional transportation of rhodamine 123 and cyclosporine A in Caco-2 cell model(P < 0. 05) in a concentration-dependent manner. Conclusion:Schizandrin B is a P-gp inhibitor,while it isn’t a P-gp substrate.
ABSTRACT
OBJECTIVE: To examine the effects of TPGS 1000 and Soluplus on the transport of ginsenoside CK in Caco-2 cell model. METHODS: The effects of TPGS 1000 and Soluplus at different concentrations on ginsenoside CK were evaluated by using Caco-2 cell model. The concentration of ginsenoside CK in cell was examined by ultra high pressure liquid chromatography (UPLC) method. The apparent permeability coefficient (Papp) and the efflux ratio were calculated. RESULTS: When the proportion of ginsenoside CK to TPGS 1000 or Soluplus was 1:1, 1:3, and 1:9, the absorption of ginsenoside CK significantly increased. The efflux and efflux ratio both decreased significantly (P<0.05). TPGS 1000 had more significant promotion effect on the transport of ginsenoside CK than the same dose of soluplus at the same ratio (P<0.05). CONCLUSION: In Caco-2 cell model, both TPGS 1000 and Soluplus can significantly promote the absorption of ginsenoside CK.
ABSTRACT
Aim To study absorption characteristics of SM-1 , a novel anti-tumor agent , to provide a research basis for the druggability evaluation of SM-1 and formu-lation design. Methods Caco-2 cell monolayer model and in situ single-pass intestinal perfusion rat model were used to study the absorption characteristics of SM-1 , and the absorption of SM-1 in vivo was evaluated through absolute bioavailability study in rats. Results The results of cell monolayer model showed that cu-mulative absorption and efflux of SM-1 increased line-arly with concentration ( 10 ~40 mg · L-1 ) . There were no significant differences in Papp with different concentrations ( P>0. 05 ) . SM-1 was absorbed mainly through passive diffusion. The intestinal perfusion re-sults showed that Ka and Pef of SM-1 had no significant differences ( P > 0. 05 ) , when the concentrations ranged from 25 to 100 mg · L-1 . SM-1 entered the systemic circulation mainly via on passive diffusion, indicating it is a compound with high permeability. The absorption of SM-1 in duodenum was superior to other intestinal segments ( P 0. 05 ) . The absolute bioavailability of SM-1 in rats was 29. 3%. Conclusion The membrane perme-ability of SM-1 is high and it can be absorbed by intes-tine well. The absorption mechanism of SM-1 is pas-sive diffusion, and it possibly escapes from the efflux transporter protein. The absolute bioavailability of SM-1 in rats is low.
ABSTRACT
OBJECTIVE: To study the transport properties of puerarin across Caco-2 cell membrane and determine the influence of Radix Angelicae Dahuricae extract on the transport of puerarin using the well-characterized, human-based intestinal Caco-2 cell model as a platform. METHODS: The characteristics of the bidirectional transport of puerarin was investigated. The effects of time, drug concentration, pH, P-gp inhibitor and MRP inhibitor on the absorption of puerarin were observed. Then the influence of the extract of Radix Angelicae Dahuricae on the transport of puerarin was studied. Drug concentration was measured by HPLC and the apparent permeability coefficients (Papp) and apparent permeability ratio (PDR) were calculated. RESULTS: Puerarin was better absorbed in weak acid of pH5.5. The Ka and Papp of puerarin was of concentration-dependent, and the transport showed saturation with increasing time and concentration. When P-gp/MRP inhibitors were added to the model, the Papp AP-BL of puerarin in Caco-2 cell increased and the PappBL-AP/PappAP-BL puerarin reduced. The absorption of puerarin was improved when combined with Radix Angelicae Dahuricae. CONCLUSION The intestinal absorption of puerarin in Caco-2 cell monolayer model is mainly a passive diffusion process, and active transportation mediated by P-gp and MRP transporter is also involved. Radix Angelicae Dahuricae can enhance the intestinal absorption of puerarin.
ABSTRACT
Objective To assess iron bioavailability of three iron-biofortified maizes using an in vitro digestion/ Caco-2 cell culture model. Method Three maize varieties rich in iron (Zhongtie 2, 3 and 4) and two maize varieties with lower content of iron (Zhengda 818 and 619) were pulverized, and the content of iron and phosphorus in each maize variety was measured. After digestion the iron bioavailability per g food was determined by using Caco-2 cell ferritin formation per mg cell protein as indicator. Results The iron content (33.250 mg/kg), iron bioavailability and the iron bioavailability per g food of Zhongtie 2 maize was the highest among all varieties, but its phosphorus content was lower. The maize varieties with the next higher iron bioavailability were Zhongtie 3 and Zhengda 818, and the lowest was Zhengda 619. Conclusion Zhongtie 2 maize contained the hightest content and bioavailability of iron,so it was optimal to use for the following human trials.
ABSTRACT
Objective To research the absorption mechanism of paeoniflorin across Caco-2 monolayer model. Methods Depending on the Caco-2 cell monolayers drug transport model to study the double transport mechanism of paeoniflorin. To explore the effect of paeoniflorin absorption by time and drug concentration, the drug concentration was determined through the use of HPLC instrument and the Papp was calcalatad. Results In the Caco-2 monolayer model, the transport of paeoniflorin form Apical (AP) to Basolateral (BL) is similar to the transport form BL to AP. Conclusion The main mechanism of the paeoniflorin intestinal absorption in the Caco-2 monolayer model is passive transference.
ABSTRACT
AIM:To research the absorption mechanism of aesculin across Caco-2 monolayer model.METHODS:The Caco-2 cell monolayers drug transport model was assigned to study the double transport mechanism of aesculin to explore the absorption of aesculin according as time and drug concentration determined through HPLC and the P_ app was calcalated.RESULTS:In the Caco-2 monolayer model,the transport of aesculin form Apical to Basolateral was similar to the transport form basolateral to apical.CONCLUSION:The main mechanism of the aesculin intestinal absorption in the Caco-2 monolayer model is passive transference.
ABSTRACT
The absorption process is an important factor in determining the bioavailability of orally administered drugs. however, the absorption mechanism of many drugs is not clear. Caco-2 cell model is the best in vitro absorption model nowadays. It is widely used in the research on drug absorption process and absorption mechanism, especially in the aspect of traditional Chinese medicine absorption, the use of Caco-2 cell model has become the hot spot recently. Mo- reover, Caco-2 cell model is also applied in the research on drug metabolism. Therefore, Caco-2 cell model will become an important method in the research of drug absorption, and will be helpful to accelerate the process of new drug screening and development.