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OBJECTIVEP: To investigate the effect of flavonoids and triterpenoids on the function of organic anion transporting polypeptide 1B3. METHODS: Natural products such as flavonoids and triterpenoids are widely present in traditional Chinese medicine and daily diets. In the present study, CHO cells stably expressing OATP1B3 and its fluorescent substrate fluorescein methotrexate were employed to investigate the effect of 21 natural products on the function of OATP1B3. RESULTS: Mulberrin, glycyrrhetinic acid, glycyrrhizic acid, quercitrin, quercetin, and chrysanthemum stem-leaf flavonoids showed significant inhibitory effects on OATP1B3-mediated uptake of fluorescein methotrexate, with IC50 values being of 3.6, 3.8, 7.5, 9.0, 10.1 μmol•L-1, and 4.1 μg•mL-1, respectively. The IC50 value of glycyrrhetinic acid on OATP1B3 was comparable to its blood concentration in clinics, indicating an OATP1B3-mediated drug-drug interaction could occur. CONCLUSION: Some flavonoids and triterpenoids are OATP1B3 inhibitors. When patients take medications of OATP1B3 substrates, care should be taken to avoid coadmistration of drugs or food containing these inhibitors to circumvent the occurrence of adverse drug interactions.
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Objective To establish double-transfected Madin-Darby canine kidney (MDCK) [Ⅱ cells expressing human organic anion transporting polypeptide 1B1 (hOATP1B1) and multidrug resistanceassociated protein 2 (hMRP2)and to testify their functions,moreover,to study the transcellur transport of indoleamine 2,3-dioxygenase (IDO) inhibitor 1-methyltryptophan (1-MT) in the transfectants.Methods hOATP1B1/hMRP2 eukaryotic vectors pVITRO2-SLCO1B1-ABCC2 was obtained by genetic engineering method and then transfected into MDCK cells.Stably expressed MDCK cells were screened by using the geneticin G418.Real-time PCR,Western blot analysis and immuno fluorescent confocal microscopy were used to verify the proteins expression.Transport of the representative substrate pravastatin in different pH values and substrate concentrations and 1-MT were evaluated using the double transfectants.Results MDCK-OATP1B1/MRP2 was successfully established.Pravastatin displayed the optimal transcellular transport when pH value was 6.5.Transport of pravastatin demonstrated the concentration-dependent in the concertation range of 0) to 500 μmol/L.Transport of 1-MT showed no significant difference in MDCK cells and transfectants.Conclusions MDCK-OATP1B1/MRP2 was successful established;1-MT was not the substrate of OATP1B1 or MRP2 protein;and the eatablished double transfectant cell lines can be used to evaluate OATP1B1/MRP2-medicated transport of xenobiotics (e.g.new drug candidates) and endogenous compounds (e.g.bilirubin).
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This study was designed to explore the effect and mechanism of miR-206/miR-613 on the expression of OATP1B1 gene. Bioinformatic analysis was used to predict the potential miRNAs target sites in 3'-untranslated region (3'-UTR) of OATP1B1 mRNA. The expression level of miR-206/miR-613 and OATP1B1 mRNA and protein was determined with RT-qPCR and Western blot, respectively. Luciferase assay was used to explore the exact mechanism of the effect of miR-206/miR-613 on the expression of OATP1B1 mRNA and protein. The results showed that the seed sequences of miR-206/miR-613 has perfect complementary with 3'-UTR of OATP1B1 mRNA in terms of sequence specificity. The secondary structure between miR-206/miR-613 and 3'-UTR of OATP1B1 mRNA was rather stable. The OATP1B1 protein level was down-regulated by 24.7%, 38.8% by overexpression of miR-206/miR-613. The expression was up-regulated by 25%, 38.2% by inhibition of miR-206/miR-613. However, overexpression or inhibition of miR-206/miR-613 had no effect on the expression of OATP1B1 mRNA. The luciferase activity of pMIR/OATP1B1-WT luciferase reporter gene was decreased by 35% and 30% through overexpression of miR-206/miR-613. The expression was increased by 33.1% and 32.5% through inhibition of miR-206/miR-613. When the binding sites in the 3'-UTR of OATP1B1 mRNA complementary with miR-206/miR-613 was mutated, overexpression or inhibition of miR-206/miR-613 had no effect on the luciferase activity. Collectively, miR-206/miR-613 post-transcriptionally regulates the expression of OATP1B1 protein by directly targeting the 3'-UTR of OATP1B1 mRNA.
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The aim of this study is to evaluate the efficacy of total saponins of Dioscorea (TSD), an extract of the Chinese herbal Bi Xie, on hyperuricemia and to elucidate the underlying mechanisms. The rat hyperuricemia model was established by administration of adenine. Thirty-two rats were randomly allocated into 4 groups: model group, low/high-dose TSD-treated groups, and allopurinol-treated group. Meanwhile, 8 rats were used as normal controls. Serum uric acid (UA), blood urea nitrogen (BUN), serum creatinine (Scr), and organic anion transporting polypeptide 1A1 (OATP1A1) levels were measured. Comparison between the model group and treatment (allopurinol and TSD) groups showed the serum UA levels were significantly decreased in treatment groups. TSD had similar effects to allopurinol. It was found that the OATP1A1 protein expression levels in treatment groups were higher than in model group and normal controls. And different from the allopurinol-treated groups, TSD-treated group had elevated OATP1A1 expression levels in the stomach, liver, small intestine and large intestine tissues. It was suggested that TSD may facilitate the excretion of UA and lower UA levels by up-regulating OATP1A1 expression.
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Animals , Male , Rats , Creatinine , Blood , Dioscorea , Chemistry , Drugs, Chinese Herbal , Pharmacology , Therapeutic Uses , Hyperuricemia , Drug Therapy , Intestines , Metabolism , Liver , Metabolism , Organic Anion Transporters, Sodium-Independent , Genetics , Metabolism , Rats, Sprague-Dawley , Saponins , Pharmacology , Therapeutic Uses , Stomach , Metabolism , Up-Regulation , Uric Acid , BloodABSTRACT
Objective To investigate the relationship between severe toxicity during high-dose methotrexate (HD-MTX) chemotherapy and 29 related factors including SLCO1B1 521T ＞ C genovariation,and to enhance drug safety.Methods Eighty-two children with acute lymphoblastic leukemia (ALL) received HD-MTX chemotherapy.The regimen was MTX 3-5 g/m2 continuous infusion for 24 hours.The polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique was used to detect the patients' genotypes of SLCO1B1 T521C polymorphism,which was the coding gene of organic anion transporting polypeptide 1 B1 (OATP1 B1).Haematological,gastrointestinal and hepatic toxicities in 1-10 days after HD-MTX administration were observed and graded according to Common Terminology Criteria for Adverse Events (CTCAE,version 4.02).The patients were divided into two groups based on toxicity grades:case group (grades Ⅲ-Ⅴ) and normal group (grades 0-]]).The differences of 29 variates including biology features,biochemical indicators,SLCO1B1 T521 C polymorphism and etc.were compared between the two groups by univariate analysis,and the significant factors were found out.The final predictive model of severe HD-MTX-related toxicity was set up through Logistic regression analysis.Receiver operating characteristic (ROC) curve of predictor was drawn based on final model in order to evaluate its predictive ability.Results There were only 4 significant different variates between case group and normal group (P ＜ 0.05),including SLCO1B1 T521C polymorphism,serum MTX concentrations at 72 hours after starting MTX infusion (C72h),the ratios of 7-hydroxy-MTX (the metabolin of MTX) to MTX concentrations at 48 hours (k48 h),and frequency of k48 h ≤2.Based on a multivariate logistic regression analysis,only SLCO1B1 521T＞ C genovariation (odds ratio 18.489,95％ confidence interval 5.413-63.157)was the significant independent predictor for severe HD-MTX-related toxicity.The area under ROC (95％ confidence interval) of SLCO1B1 521T ＞ C genovariation as the predictor for severe HD-MTX-related toxicity was 0.776 (0.653-0.899),which had significant diagnositic value (P ＜ 0.05).Conclusions There is higher risk of severe HD-MTX-related toxicity while patients having SLCO1B1 521T ＞ C genovariation.Clinician should consider it and take some protective measures.
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Objective To investigate influences of paeonol on mRNA expression and function of drug transporters BCRP and SLCO1B1 in HepG2 cell.Methods Cell counting Kit-8 assay was used to detect the viability of HepG2 cells;Real-time fluorescent quantitative PCR (qPCR) was performed to measure the expressions of BCRP and SLCO1B1 mRNAs; flow cytometry was applied to determine the transport functions of BCRP and SLCO1B1. Results Paeonol (2-8μg/mL) did not decrease HepG2 cell survival rate, but 16 μg/mL paeonol significantly reduced cell survival rate (P<0.05). Paeonol(2-8μg/mL)significantly induced the mRNA expression and function of drug transporters BCRP and SLCO1B1(P <0.05).Compared with control group, transcription level of paeonol group’s BCRP and SLCO1B1 drug transporters obviously up-regulated, the of translocation efficiency of substrate specificity increased significantly (P <0.05).Conclusion Paeonol can induce drug hepatocellular transporters BCRP and SLCO1B1 gene expression, thereby promote the substrate transport the transmembrane.It is indicated that the drug combination of paeonol and BCRP and SLCO1B1 transporters, there may be a risk of drug interactions.
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OBJECTIVE:To explore the effects of Cangfu daotan decoction on expression of organic anion transporting poly-peptide(oatp4a1)and level of sex hormone in the endometrium and ovary tissues of rats with obesity-type polycystic ovarian syn-drome(PCOS). METHODS:Obesity-type PCOS rat models were established. 50 rats were randomized into a normal control(iso-metric normal saline)group,a model(isometric normal saline)group,a metformin(0.043 g/kg)group and Cangfu daotan decoc-tion high-dose and low-dose [5.68 and 1.42 g(medicinal materials)/kg] groups. The rats were given drugs ig once a day for 14 con-secutive days. The expression of oatp4a1 protein in the endometrium and ovaries of the rats was determined by ECL and Western blot. The levels of luteinizing hormone(LH),follicle stimulating hormone(FSH),testosterone(T)and estradiol(E2)in rat’s se-rum were detected by ELISA. RESULTS:Compared to the normal control group,those in the model group had weaker expression of oatp4a1 protein in the endometrium and ovaries,higher levels of serum LH,LH/FSH and T,lower levels of serum FSH and E2. There were statistical significances(P<0.01). Compared to the model group,those in metformin group,Cangfu daotan decoction high-dose and low-dose group had higher expression of oatp4a1 protein in the endometrium and ovaries,lower levels of LH/FSH and T,higher levels of serum E2;those in metformin group and Cangfu daotan decoction high-dose group had lower levels of serum LH,higher levels of serum FSH. There were statistical significances(P<0.01 or P<0.05). CONCLUSIONS:Cangfu daotan decoc-tion can increase the expression of oatp4a1 in the endometrium and ovaries of obesity-type PCOS model rat,alleviate phlegmy dampness and regulate the level of sex hormone.
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Objective To analyze the relationship between the genetic polymorphisms of organic anion transporting polypeptide (SLCO1B1 and SLCO1B3) and mycophenolic acid ( MPA)pharmacokinetics in Chinese kidney transplant recipients. Methods Gene mutations (SLCO1B3T334G, SLCO1B1 A338G) were detected in 68 recipients by PCR-LDR. The plasma samples were collected and blood concentration of MPA was measured on the 28 th day after transplantation. The area under the curve (AUC)0-12 of MPA in different genotype recipients was compared to analyze the correlation between single nucleotide polymorphisms (SNPs) and MPA pharmacokinetics. Results MPA AUC0-12 was higher in SLCO1B3 T334G GG carriers group than in TT carriers [(54. 54 ±14.40)vs(37.30±12.88)mg·h·L-1,(P=0.052)].However,there was no difference in MPA AUC0-12 among each genotype of SLCO1B1 A338G (P>0. 05). Conclusion Genetic polymorphisms of SLCO1B3 affect interindividual variety in plasma MPA concentration in Chinese kidney transplantation recipients.
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This paper reports on issues relating to the optimal use of gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid magnetic resonance imaging (Gd-EOB-DTPA MR imaging) together with the generation of consensus statements from a working group meeting, which was held in Seoul, Korea (2010). Gd-EOB-DTPA has been shown to improve the detection and characterization of liver lesions, and the information provided by the hepatobiliary phase is proving particularly useful in differential diagnoses and in the characterization of small lesions (around 1-1.5 cm). Discussion also focused on advances in the role of organic anion-transporting polypeptide 8 (OATP8) transporters. Gd-EOB-DTPA is also emerging as a promising tool for functional analysis, enabling the calculation of post-surgical liver function in the remaining segments. Updates to current algorithms were also discussed.
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Humans , Algorithms , Contrast Media , Diagnosis, Differential , Gadolinium DTPA , Liver Diseases/diagnosis , Liver Function Tests , Magnetic Resonance Imaging , Organic Anion Transporters, Sodium-Independent/metabolism , Postoperative Complications/diagnosis , Practice Guidelines as TopicABSTRACT
Thyroid hormones play important roles in growth, development, and metabolism of various cells and tissues. It has been assumed for a long time that thyroid hormones are lipophilic and enter cells by passive diffusion, but it has become increasingly clear that cellular uptake and efflux of thyroid hormones are mediated by transporters. The discovery of these thyroid hormone transporters will lead to a better understanding of the tissuespecific regulation of thyroid hormones.
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A function of the kidney is elimination of a variety of xenobiotics ingested and wasted endogenous compounds from the body. Organic anion and cation transport systems play important roles to protect the body from harmful substances. The renal proximal tubule is the primary site of carrier-mediated transport from blood into urine. During the last decade, molecular cloning has identified several families of multispecific organic anion and cation transporters, such as organic anion transporter (OAT), organic cation transporter (OCT), and organic anion-transporting polypeptide (oatp). Additional findings also suggested ATP-dependent organic ion transporters such as MDR1/P-glycoprotein and the multidrug resistance-associated protein (MRP) as efflux pump. The substrate specificity of these transporters is multispecific. These transporters also play an important role as drug transporters. Studies on their functional properties and localization provide information in renal handling of drugs. This review summarizes the latest knowledge on molecular properties and pharmacological significance of renal organic ion transporters.