[Studies on absorption and transportation of coumarins in Angelica dahurica 'Yubaizhi' across human intestinal epithelial by using human Caco-2 cell monolayers].

The absorption is the key to the resulted efficacy of orally administered drugs and the small intestine is the main site to absorb the orally administered drug. In this paper, internationally recognized human colon adenocarcinoma cell line(Caco-2) monola-yer model which can simulate small intestinal epithelial cell was used to comparatively study the absorption and transportation diffe-rences of total coumarins and main individual coumarin in Angelica dahurica 'Yubaizhi' by separately using 6-and 12-well plates. It was found that apparent permeability coefficient(P_(app)) values of oxypeucedanin hydrate, byakangelicin and phellopterin were at the quantitative degree of 1 × 10~(-5) cm·s~(-1) when the individual administration was conducted independently, indicating that they were well-absorbed compounds. P_(app) ratio of their bi-directional transportation was close to 1, indicating that they can be absorbed across Caco-2 monolayer by passive diffusion mechanism without carrier mediation during the transportation. The similar trend of transportation was also observed for imperatorin, isoimperatorin and bergapten. The P_(app) values of oxypeucedanin hydrate, byakangelicin and bergapten were at quantitative degree of 1 × 10~(-5) cm·s~(-1) when the administration of total coumarins in Angelica dahurica 'Yubaizhi' was conducted, indicating that they were well-absorbed compounds. The results were consistent with those of independent administration of individual coumarins. Whereas, the P_(app) values of imperatorin, phellopterin and isoimperatorin in the total coumarins decreased, indicating that the interaction between compounds may exist although the P_(app) value ratio of bi-directional transportation was between 0.5 and 1.5. The results laid the foundation for intestinal absorption study of Angelica dahurica 'Yubaizhi' coumarins in compound Chinese medicine.

Studies on absorption and transportation of coumarins in Angelica dahurica 'Yubaizhi' across human intestinal epithelial by using human Caco-2 cell monolayers / 中国中药杂志

The absorption is the key to the resulted efficacy of orally administered drugs and the small intestine is the main site to absorb the orally administered drug. In this paper, internationally recognized human colon adenocarcinoma cell line(Caco-2) monola-yer model which can simulate small intestinal epithelial cell was used to comparatively study the absorption and transportation diffe-rences of total coumarins and main individual coumarin in Angelica dahurica 'Yubaizhi' by separately using 6-and 12-well plates. It was found that apparent permeability coefficient(P_(app)) values of oxypeucedanin hydrate, byakangelicin and phellopterin were at the quantitative degree of 1 × 10~(-5) cm·s~(-1) when the individual administration was conducted independently, indicating that they were well-absorbed compounds. P_(app) ratio of their bi-directional transportation was close to 1, indicating that they can be absorbed across Caco-2 monolayer by passive diffusion mechanism without carrier mediation during the transportation. The similar trend of transportation was also observed for imperatorin, isoimperatorin and bergapten. The P_(app) values of oxypeucedanin hydrate, byakangelicin and bergapten were at quantitative degree of 1 × 10~(-5) cm·s~(-1) when the administration of total coumarins in Angelica dahurica 'Yubaizhi' was conducted, indicating that they were well-absorbed compounds. The results were consistent with those of independent administration of individual coumarins. Whereas, the P_(app) values of imperatorin, phellopterin and isoimperatorin in the total coumarins decreased, indicating that the interaction between compounds may exist although the P_(app) value ratio of bi-directional transportation was between 0.5 and 1.5. The results laid the foundation for intestinal absorption study of Angelica dahurica 'Yubaizhi' coumarins in compound Chinese medicine.

Effects of low molecular weight chitosan and its nanoparticles on intestinal permeability of Panax notoginseng saponins / 中草药

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.

Evaluation of Marine Diindolinonepyrane in Vitro and in Vivo: Permeability Characterization in Caco-2 Cells Monolayer and Pharmacokinetic Properties in Beagle Dogs.

A marine fibrinolytic compound was studied for use in thrombolytic therapy. Firstly, the absorption and transportation characteristics of 2,5-BHPA (2,5-BHPA:2,5-Bis-[8-(4,8-dimethyl-nona-3,7-dienyl)-5,7-dihydroxy-8-methyl-3-keto-1,2,7,8-tertahydro-6H-pyran[a]isoindol-2-yl]-pentanoic acid, a novel pyran-isoindolone derivative with bioactivity isolated from a rare marine microorganism in our laboratory) in the human Caco-2 cells monolayer model were investigated. We collected 2,5-BHPA in the cells to calculate the total recovery, and its concentration was analyzed by LC/MS/MS (Liquid Chromatography/ Mass Spectrum/ Mass Spectrum). The results showed that 2,5-BHPA has low permeability and low total recoveries in the Caco-2 cells membrane. Pharmacokinetics and tissue distribution of 2,5-BHPA were investigated in beagle dogs using HPLC (High Performance Liquid Chromatography) after intravenous administration of three different doses (7.5, 5.0, 2.5 mg·kg-1). Pharmacokinetic data indicated that 2,5-BHPA fitted well to a two-compartment model. Elimination half-lives (T1/2) were 49 ± 2, 48 ± 2, and 49 ± 2 min, respectively; the peak concentrations (Cmax) were 56.48 ± 6.23, 48.63 ± 5.53, and 13.64 ± 2.76 µg·mL-1, respectively; clearance rates (CL) were 0.0062 ± 0.0004, 0.0071 ± 0.0008, and 0.0092 ±0.0006 L·min-1·kg-1, respectively; mean retention times (MRT) were 28.17 ± 1.16, 26.23 ± 0.35, and 28.66 ± 0.84 min, respectively. The low penetrability of 2,5-BHPA indicated that the intravenous route of administration is more appropriate than the oral route. Meanwhile, 2,5-BHPA showed a good pharmacokinetic profile in beagle dogs. The tissue distribution showed that 2,5-BHPA could quickly distribute into the heart, intestines, liver, stomach, spleen, lungs, testicles, urine, intestine, kidneys, brain, and feces. The concentration of 2,5-BHPA was higher in the liver and bile. Interestingly, 2,5-BHPA was detected in the brain. Taken together, the above results suggested that our work might be beneficial in the development of agents for thrombolytic treatment.

Research on intestinal absorption characteristics of meglucumin cocrystal in rats / 中草药

Objective: Meglucumin cocrystal (MGC) is a new cocrystal compound which consists of curcumin with meglumine by hydrogen bond. The intestinal absorption parameter changes of MGC would be observed and be compared with curcumin. Methods: The intestine in rats was cannulated for in situ perfusion to study the absorption mechanism of MGC; UV was used to determine the concentration of MGC, to calculate the order of the absorption rate constants (Ka), and apparent permeability coefficients (Papp). Results: The Ka and Papp of MGC in the duodenum has significantly increased compared with the colon (P0.05) in other isolated regions of the intestine. The order was: duodenum>jejunum>ileum>colon; And that of Papp was: duodenum>jejunum>colon>ileum. The Ka and Papp in the whole intestine were (9.966±0.030)×10-3 min-1and (6.871±0.013)×10-3 cm/min respectively for the MGC which were 1.53 times and 2.21 times higher than these of curcumin. Conclusion: MGC is a better intestinal absorption characteristic than these of curcumin, suggesting that the bioavailability of MGC may be increased.

Transportation of 8-isopropylaminomethyl hesperitin(IPHP) across human intestinal epithelial by using Caco-2 cells / 中国药理学通报

Aim To study the mechanism of 8-isopro-pylaminomethyl hesperitin ( IPHP ) intestinal absorp-tion using Caco-2 cell lines. Methods Using Caco-2 cell lines as an intestinal epithelial cell model, the effects of drug concentration, temperature, pH, P-gly-coprotein ( P-gp) inhibitor verapamil and multidrug re-sistance protein 2 ( MRP2 ) inhibitors MK-571 or pro-benecid on IPHP transport across Caco-2 cell lines were all investigated. Results The transportation of IPHP was related to drug concentration. The Papp ( AP-BL) ( × 10 -5) was (2. 21 ± 0. 200) cm·s-1,(3. 56 ± 0. 306) cm·s-1,(3. 81 ± 0. 179) cm·s-1,(4. 23 ± 0. 229 ) cm · s-1 , ( 4. 17 ± 0. 262 ) cm · s-1 , re-spectively, and Papp(BL-AP) ( × 10 -5) was (3. 57 ±0. 209) cm·s-1,(4. 51 ± 0. 113) cm·s-1,(4. 97 ± 0. 229) cm·s-1,(5. 24 ± 0. 550) cm·s-1,(5. 07 ± 0. 557) cm·s-1,respectively. Efflux rate was 1. 61, 1. 26,1. 3,1. 23,1. 21,respectively. Temperature and pH both influenced the transport, While the P-gp in-hibitor verapamil had no effect on the transport of IPHP. MRP2 inhibitors MK-571 or probenecid led to an apparent decrease in the efflux of IPHP. Conclu-sion The results suggest that the transport of IPHP is mainly passive diffusion, and MRP2 but not P-gp may be involved in the transport of IPHP.

Transport of ginkgolides with different lipophilicities based on an hCMEC/D3 cell monolayer as a blood-brain barrier cell model.

AIMS: In this report, the transport of ginkgolides with different lipophilicities was investigated using an hCMEC/D3 cell monolayer as a blood-brain barrier (BBB) cell model in vitro in an attempt to explain ginkgolide transport path mediated by lipophilicity. MAIN METHODS: The log P values of ginkgolides were determined by measuring the distribution of the molecule between oil and water. Additionally, the cytotoxicity of ginkgolides on hCMEC/D3 cells was assayed with the MTT method. Ginkgolide contents were determined with an ultra performance liquid chromatograph equipped with an evaporative light scattering detector (ULPC-ELSD) method. Apparent permeability coefficients (Papp) and efflux ratios (PappBL→AP/PappAP→BL) were then calculated to describe the transport characteristics of ginkgolide. KEY FINDINGS: The transport of ginkgolide A, ginkgolide B, ginkgolide C, and ginkgolide J across the hCMEC/D3 cell monolayer was non-directional. Additionally, ginkgolide C transport on the cell monolayer was time- and concentration-dependent in the paracellular pathway controlled by cytochalasin D (a tight junction modulator). The transport of ginkgolide N, ginkgolide L, and ginkgolide K across the cell monolayer displayed clear directionality at low ginkgolide concentrations. This behavior indicated that the transport of ginkgolide N, ginkgolide L, and ginkgolide K was influenced by the transcellular pathway containing an efflux protein accompanied by the paracellular pathway for passive diffusion. Additionally, the transport of ginkgolide K was increased significantly by co-culturing with a P-gp inhibitor. SIGNIFICANCE: These findings provide important information for elucidating ginkgolide transport pathways and may be beneficial for the design of ginkgolide molecules with high neuroprotective effects.

Evaluation of blood-brain barrier and blood-cerebrospinal fluid barrier permeability of 2-phenoxy-indan-1-one derivatives using in vitro cell models.

2-Phenoxy-indan-1-one derivatives (PIOs) are a series of novel central-acting cholinesterase inhibitors for the treatment of Alzheimer's disease (AD). The adequate distribution of PIOs to the central nervous system (CNS) is essential for its effectiveness. However, articles related with their permeability in terms of CNS penetration across the blood-brain barrier (BBB) and blood-cerebrospinal fluid barrier (BCSFB) have not been found. This study was undertaken to evaluate the in vitro BBB and BCSFB transport of PIOs using Madin-Darby canine kidney (MDCK), MDCK-MDR1 and Z310 cell line models. As a result, the transepithelial transport of PIOs did not differ between MDCK and MDCK-MDR1, and the result suggested that PIOs were not substrates for P-gp, which means that multidrug resistance (MDR) function would not affect PIOs absorption and brain distribution. High permeability of PIOs in Z310 was found and it suggested that PIOs had high brain uptake potential. The experiment also showed that PIOs had inhibitory effects on the MDR1-mediated transport of Rhodamine123 with an IC50 value of 40-54 µM. And we suggested that 5,6-dimethoxy-1-indanone might be the pharmacophoric moiety of PIOs that interacts with the binding site of P-gp.

Absorption and transport characteristic of paeoniflorin and its derivatives in model of Caco-2 cell monolayers / 中草药

Objective: To study the absorption and transport characteristic of paeoniflorin (PF), oxypaeoniflorin (OP), benzoylpaeoniflorin (BP), tetraacetylpaeoniflorin (TP), pentaacetylpaeoniflorin (PP), and pentacacetylalbiflorin (PA) in human colon adenocarcinoma cell line Caco-2 cell monolayer model. Methods: The Caco-2 cell monolayers were used as an intestinal epithelial cell model. The permeability of the tested compounds from apical (AP) side to basolateral (BL) side or from BL side to AP side was evaluated. The concentration of the tested compounds was measured by HPLC coupled with UV detector. The transport parameters and apparent permeability coefficients (Papp) were calculated, and the Papp values were compared with the reported values for model compounds, Propranolol and Atenolol. Results: The Papp values of PF in the bi-directional transport and atenolol were at the quantitative degree of 10-7 cm/s. Whereas those of OP, BP, TP, PP, and PA were between atenolol and propranolol used as a control substance for low and high permeability, respectively. The absorption and transport of the tested compounds were concentration-dependent at the concentration range of 10-200 μmol/L for PF, OP, and BP, 10-150 μmol/L for TP and PA, and 10-100 μmol/L for PP. Conclusion: The six tested compounds could be absorbed across the intestinal epithelial cells by passive diffusion mechanism. PF is poorly absorbed compound and OP, BP, TP, PP, and PA are moderately absorbed compounds. BP has a role to promote atenolol uptake transporters in Caco-2 cell monolayer model.